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Sample records for predict attentional modulation

  1. Baseline Shifts do not Predict Attentional Modulation of Target Processing During Feature-Based Visual Attention

    PubMed Central

    Fannon, Sean P.; Saron, Clifford D.; Mangun, George R.

    2007-01-01

    Cues that direct selective attention to a spatial location have been observed to increase baseline neural activity in visual areas that represent a to-be-attended stimulus location. Analogous attention-related baseline shifts have also been observed in response to attention-directing cues for non-spatial stimulus features. It has been proposed that baseline shifts with preparatory attention may serve as the mechanism by which attention modulates the responses to subsequent visual targets that match the attended location or feature. Using functional MRI, we localized color- and motion-sensitive visual areas in individual subjects and investigated the relationship between cue-induced baseline shifts and the subsequent attentional modulation of task-relevant target stimuli. Although attention-directing cues often led to increased background neural activity in feature specific visual areas, these increases were not correlated with either behavior in the task or subsequent attentional modulation of the visual targets. These findings cast doubt on the hypothesis that attention-related shifts in baseline neural activity result in selective sensory processing of visual targets during feature-based selective attention. PMID:18958221

  2. Spatial Attention and Temporal Expectation Under Timed Uncertainty Predictably Modulate Neuronal Responses in Monkey V1.

    PubMed

    Sharma, Jitendra; Sugihara, Hiroki; Katz, Yarden; Schummers, James; Tenenbaum, Joshua; Sur, Mriganka

    2015-09-01

    The brain uses attention and expectation as flexible devices for optimizing behavioral responses associated with expected but unpredictably timed events. The neural bases of attention and expectation are thought to engage higher cognitive loci; however, their influence at the level of primary visual cortex (V1) remains unknown. Here, we asked whether single-neuron responses in monkey V1 were influenced by an attention task of unpredictable duration. Monkeys covertly attended to a spot that remained unchanged for a fixed period and then abruptly disappeared at variable times, prompting a lever release for reward. We show that monkeys responded progressively faster and performed better as the trial duration increased. Neural responses also followed monkey's task engagement-there was an early, but short duration, response facilitation, followed by a late but sustained increase during the time monkeys expected the attention spot to disappear. This late attentional modulation was significantly and negatively correlated with the reaction time and was well explained by a modified hazard function. Such bimodal, time-dependent changes were, however, absent in a task that did not require explicit attentional engagement. Thus, V1 neurons carry reliable signals of attention and temporal expectation that correlate with predictable influences on monkeys' behavioral responses. PMID:24836689

  3. Unconscious attention modulates the silencing effect of top-down predictions.

    PubMed

    Chen, Xu; Ran, Guangming; Zhang, Qi; Hu, Tianqiang

    2015-07-01

    The brain is considered to be proactive in that it continuously generates predictions about external environment stimuli. Recent Bayesian models of perception have demonstrated that prediction and attention operate synergistically to optimize stimulus processing. However, the relation between prediction and unconscious attention remains unclear given the relative neglect of unconscious attention in scholarly literatures. To investigate this issue, twenty participants (12 women) performed an orientation identification task in which a circular grating appeared either in the left or in the right visual field in a single 30-40min session, during which 64-channel EEG data were acquired. Behavioral results showed an unconscious-attended effect and a facilitated effect. Importantly, prediction-related P1 and N1 silencing effects were observed in the unconscious-attended condition, probably reflecting that unconscious attention improves the precision of top-down predictions at an early stage of processing, thereby increasing the synaptic gain of predictor neurons. Moreover, unlike the early ERP components, P3 revealed a reversed pattern of results, which displayed a silencing effect of prediction only in the unattended condition, suggesting that the influence of unconscious attention on the silencing effect may change over time.

  4. Attention modulates visual size adaptation.

    PubMed

    Kreutzer, Sylvia; Fink, Gereon R; Weidner, Ralph

    2015-01-01

    The current study determined in healthy subjects (n = 16) whether size adaptation occurs at early, i.e., preattentive, levels of processing or whether higher cognitive processes such as attention can modulate the illusion. To investigate this issue, bottom-up stimulation was kept constant across conditions by using a single adaptation display containing both small and large adapter stimuli. Subjects' attention was directed to either the large or small adapter stimulus by means of a luminance detection task. When attention was directed toward the small as compared to the large adapter, the perceived size of the subsequent target was significantly increased. Data suggest that different size adaptation effects can be induced by one and the same stimulus depending on the current allocation of attention. This indicates that size adaptation is subject to attentional modulation. These findings are in line with previous research showing that transient as well as sustained attention modulates visual features, such as contrast sensitivity and spatial frequency, and influences adaptation in other contexts, such as motion adaptation (Alais & Blake, 1999; Lankheet & Verstraten, 1995). Based on a recently suggested model (Pooresmaeili, Arrighi, Biagi, & Morrone, 2013), according to which perceptual adaptation is based on local excitation and inhibition in V1, we conclude that guiding attention can boost these local processes in one or the other direction by increasing the weight of the attended adapter. In sum, perceptual adaptation, although reflected in changes of neural activity at early levels (as shown in the aforementioned study), is nevertheless subject to higher-order modulation.

  5. Affective modulation of attentional switching.

    PubMed

    Heerebout, Bram T; Todorović, Ana; Smedinga, Hilde E; Phaf, R Hans

    2013-01-01

    Affective modulation of attentional switching may have developed early in evolution and may therefore have primacy over other affective influences. This behavioral study investigated the influence of affect on attentional switching between emotionally neutral stimuli, whether limited-capacity control processes are involved, and whether attentional flexibility should be distinguished from attentional broadening. Experiment 1 showed that suboptimally presented happy faces facilitated switching from an automatized response routine, whereas angry faces had the opposite effect. In Experiment 2, participants with a dominant global (i.e., broad) or local (i.e., narrow) spatial bias switched more easily to the opposite bias after suboptimal happy faces than after neutral primes but less easily after angry faces. Affective modulation of attentional switching was probably incorporated during evolution in many more complex forms of information processing.

  6. How Attention Modulates Encoding of Dynamic Stimuli

    PubMed Central

    Oren, Noga; Shapira-Lichter, Irit; Lerner, Yulia; Tarrasch, Ricardo; Hendler, Talma; Giladi, Nir; Ash, Elissa L.

    2016-01-01

    When encoding a real-life, continuous stimulus, the same neural circuits support processing and integration of prior as well as new incoming information. This ongoing interplay is modulated by attention, and is evident in regions such as the prefrontal cortex section of the task positive network (TPN), and in the posterior cingulate cortex (PCC), a hub of the default mode network (DMN). Yet the exact nature of such modulation is still unclear. To investigate this issue, we utilized an fMRI task that employed movies as the encoded stimuli and manipulated attentional load via an easy or hard secondary task that was performed simultaneously with encoding. Results showed increased intersubject correlation (inter-SC) levels when encoding movies in a condition of high, as compared to low attentional load. This was evident in bilateral ventrolateral and dorsomedial prefrontal cortices and the dorsal PCC (dPCC). These regions became more attuned to the combination of the movie and the secondary task as the attentional demand of the latter increased. Activation analyses revealed that at higher load the prefrontal TPN regions were more activated, whereas the dPCC was more deactivated. Attentional load also influenced connectivity within and between the networks. At high load the dPCC was anti-correlated to the prefrontal regions, which were more functionally coherent amongst themselves. Finally and critically, greater inter-SC in the dPCC at high load during encoding predicted lower memory strength when that information was retrieved. This association between inter-SC levels and memory strength suggest that as attentional demands increased, the dPCC was more attuned to the secondary task at the expense of the encoded stimulus, thus weakening memory for the encoded stimulus. Together, our findings show that attentional load modulated the function of core TPN and DMN regions. Furthermore, the observed relationship between memory strength and the modulation of the dPCC points

  7. Difficulty of Discrimination Modulates Attentional Capture by Regulating Attentional Focus

    ERIC Educational Resources Information Center

    Sawaki, Risa; Katayama, Jun'ichi

    2009-01-01

    Attentional capture for distractors is enhanced by increasing the difficulty of discrimination between the standard and the target in the three-stimulus oddball paradigm. In this study, we investigated the cognitive mechanism of this modulation of attentional capture. Event-related brain potentials were recorded from participants while they…

  8. Caffeine Modulates Attention Network Function

    ERIC Educational Resources Information Center

    Brunye, Tad T.; Mahoney, Caroline R.; Lieberman, Harris R.; Taylor, Holly A.

    2010-01-01

    The present work investigated the effects of caffeine (0 mg, 100 mg, 200 mg, 400 mg) on a flanker task designed to test Posner's three visual attention network functions: alerting, orienting, and executive control [Posner, M. I. (2004). "Cognitive neuroscience of attention". New York, NY: Guilford Press]. In a placebo-controlled, double-blind…

  9. Visual search performance is predicted by the degree to which selective attention to features modulates the ERP between 350 and 600ms.

    PubMed

    Milne, Elizabeth; Dunn, Stephanie A; Freeth, Megan; Rosas-Martinez, Luisa

    2013-05-01

    Efficient visual search necessitates perception of items in the visual array, rapid classification of items as either targets or distractors, and the selection of target items. Individuals vary in the speed with which they perform these operations and can detect targets within cluttered arrays, as shown in visual search tasks. Individuals with autism spectrum disorders (ASD) show particular strengths in visual search. The aim of the current study was to develop an understanding the origin of individual variability in visual search by delineating the processes involved in feature-based target detection, and establishing which, if any, of these processes predict search efficiency. EEG was recorded while participants performed a feature-based selective attention task from which the following EEG variables were computed: P1 amplitude; P1 latency; selection negativity; induced γ-band power and P3b amplitude. These variables are considered to reflect stimulus encoding, feedback amplification of attended features, cognitive utilization and resource allocation during event classification respectively. Participants also completed a separate visual search task. Regression analyses revealed that only the ERP component associated with resource allocation during event classification (P3b) significantly predicted search efficiency. These data suggest that individual variability in visual search is related to a reduction in modulation of attention allocation to visual features. Implications for the understanding of superior visual search in individuals with ASD are discussed.

  10. Social traits modulate attention to affiliative cues

    PubMed Central

    Moore, Sarah R.; Fu, Yu; Depue, Richard A.

    2014-01-01

    Neurobehavioral models of personality suggest that the salience assigned to particular classes of stimuli vary as a function of traits that reflect both the activity of neurobiological encoding and relevant social experience. In turn, this joint influence modulates the extent that salience influences attentional processes, and hence learning about and responding to those stimuli. Applying this model to the domain of social valuation, we assessed the differential effects on attentional guidance by affiliative cues of (i) a higher-order temperament trait (Social Closeness), and (ii) attachment style in a sample of 57 women. Attention to affiliative pictures paired with either incentive or neutral pictures was assessed using camera eye-tracking. Trait social closeness and attachment avoidance interacted to modulate fixation frequency on affiliative but not on incentive pictures, suggesting that both traits influence the salience assigned to affiliative cues specifically. PMID:25009524

  11. Hemispheric modulations of the attentional networks.

    PubMed

    Spagna, Alfredo; Martella, Diana; Fuentes, Luis J; Marotta, Andrea; Casagrande, Maria

    2016-10-01

    Although several recent studies investigated the hemispheric contributions to the attentional networks using the Attention Network Test (ANT), the role of the cerebral hemispheres in modulating the interaction among them remains unclear. In this study, two lateralized versions of this test (LANT) were used to investigate theal effects on the attentional networks under different conflict conditions. One version, the LANTI-A, presented arrows as target and flankers, while the other version, the LANTI-F, had fruits as target and flankers. Data collected from forty-seven participants confirmed well-known results on the efficiency and interactions among the attentional networks. Further, a left visual field advantage was found when a target occurred in an unattended location (e.g. invalid trials), only with the LANTI-F, but not with LANTI-A. The present study adds more evidence to the hemispheric asymmetry of the orienting of attention, and further reveals patterns of interactions between the attentional networks and the visual fields across different conflicting conditions, underlying the dynamic control of attention in complex environments.

  12. Hemispheric modulations of the attentional networks.

    PubMed

    Spagna, Alfredo; Martella, Diana; Fuentes, Luis J; Marotta, Andrea; Casagrande, Maria

    2016-10-01

    Although several recent studies investigated the hemispheric contributions to the attentional networks using the Attention Network Test (ANT), the role of the cerebral hemispheres in modulating the interaction among them remains unclear. In this study, two lateralized versions of this test (LANT) were used to investigate theal effects on the attentional networks under different conflict conditions. One version, the LANTI-A, presented arrows as target and flankers, while the other version, the LANTI-F, had fruits as target and flankers. Data collected from forty-seven participants confirmed well-known results on the efficiency and interactions among the attentional networks. Further, a left visual field advantage was found when a target occurred in an unattended location (e.g. invalid trials), only with the LANTI-F, but not with LANTI-A. The present study adds more evidence to the hemispheric asymmetry of the orienting of attention, and further reveals patterns of interactions between the attentional networks and the visual fields across different conflicting conditions, underlying the dynamic control of attention in complex environments. PMID:27566000

  13. Attentional Modulation of Eye Torsion Responses

    NASA Technical Reports Server (NTRS)

    Stevenson, Scott B.; Mahadevan, Madhumitha S.; Mulligan, Jeffrey B.

    2016-01-01

    Eye movements generally have both reflexive and voluntary aspects, but torsional eye movements are usually thought of as a reflexive response to image rotation around the line of sight (torsional OKN) or to head roll (torsional VOR). In this study we asked whether torsional responses could be modulated by attention in a case where two stimuli rotated independently, and whether attention would influence the latency of responses. The display consisted of rear-projected radial "pinwheel" gratings, with an inner annulus segment extending from the center to 22 degrees eccentricity, and an outer annulus segment extending from 22 degrees out to 45 degrees eccentricity. The two segments rotated around the center in independent random walks, stepping randomly 4 degrees clockwise or counterclockwise at 60 Hz. Subjects were asked to attend to one or the other while keeping fixation steady at the center of the display. To encourage attention on one or the other segment of the display, subjects were asked to move a joystick in synchrony with the back and forth rotations of one part of the image while ignoring the other. Eye torsion was recorded with the scleral search coil technique, sampled at 500 Hz. All four subjects showed roughly 50% stronger torsion responses to the attended compared to unattended segments. Latency varied from 100 to 150 msec across subjects and was unchanged by attention. These findings suggest that attention can influence eye movement responses that are not typically under voluntary control.

  14. Noradrenergic Genotype Predicts Lapses in Sustained Attention

    ERIC Educational Resources Information Center

    Greene, Ciara M.; Bellgrove, Mark A.; Gill, Michael; Robertson, Ian H.

    2009-01-01

    Sustained attention is modulated by the neurotransmitter noradrenaline. The balance of dopamine and noradrenaline in the cortex is controlled by the DBH gene. The principal variant in this gene is a C/T change at position-1021, and the T allele at this locus is hypothesised to result in a slower rate of dopamine to noradrenaline conversion than…

  15. Multiple measures of visual attention predict novice motor skill performance when attention is focused externally.

    PubMed

    Kasper, Ryan W; Elliott, James C; Giesbrecht, Barry

    2012-10-01

    Multiple lines of evidence indicate that the control of attention and motor skill performance are related. Athletes of various skill levels differ in terms of their control over the focus of attention and directing athletes to adopt an internal or external focus of attention modulates performance. However, it is unclear (a) whether the relationship between skill level and attentional control arises from preexisting individual differences in attention or from practice of the motor skill and (b) whether the effect of adopting an internal or external focus of attention on motor performance is influenced by individual differences in attention. To address these issues, individuals were measured on three distinct attention functions - orienting, alerting, and executive - prior to engaging in a novel golf-putting task performed with either external or internal focus instructions. The results indicated that, on average, attentional functioning and putting performance were related but that the strong relationships with orienting and executive attention were only present in the group given external focus instructions. These findings suggest that individual differences in attentional abilities are predictive of novel skill performance under an external focus of attention and they shed light on the mechanisms underlying the effects of focus instructions during motor performance. PMID:22516836

  16. Attention-Modulating Effects of Cognitive Enhancers

    EPA Science Inventory

    Attention can be readily measured in experimental animal models. Animal models of attention have been used to better understand the neural systems involved in attention, how attention is impaired, and how therapeutic treatments can ameliorate attentional deficits. This review fo...

  17. The interaction between attention and motor prediction. An ERP study.

    PubMed

    Jones, Alexander; Hughes, Gethin; Waszak, Florian

    2013-12-01

    Performing a voluntary action involves the anticipation of the intended effect of that action. Interaction with the environment also requires the allocation of attention. However, the effects of attention upon motor predictive processes remain unclear. Here we use a novel paradigm to investigate attention and motor prediction orthogonally. In an acquisition phase, high and low tones were associated with left and right key presses. In the following test phase, tones were presented at random and participants attended to only one ear whilst ignoring tones presented in the unattended ear. In the test phase a tone could therefore be presented at the attended or unattended ear, as well as being congruent or incongruent with prior action-effect learning. We demonstrated early and late effects of attention as well as a later independent motor prediction effect with a larger P3a for incongruent tones. Interestingly, we demonstrated an intermediate interaction, showing an action-effect negativity (NAE) for tones which were unattended, whilst no motor prediction effect was found for attended tones. This interaction pattern suggests that attention and motor prediction are not opposing processes but can both operate to modulate prediction, providing valuable new insight into the relationship between attention and the effects of motor prediction.

  18. Musical Meter Modulates the Allocation of Attention across Time.

    PubMed

    Fitzroy, Ahren B; Sanders, Lisa D

    2015-12-01

    Dynamic attending theory predicts that attention is allocated hierarchically across time during processing of hierarchical rhythmic structures such as musical meter. ERP research demonstrates that attention to a moment in time modulates early auditory processing as evidenced by the amplitude of the first negative peak (N1) approximately 100 msec after sound onset. ERPs elicited by tones presented at times of high and low metric strength in short melodies were compared to test the hypothesis that hierarchically structured rhythms direct attention in a manner that modulates early perceptual processing. A more negative N1 was observed for metrically strong beats compared with metrically weak beats; this result provides electrophysiological evidence that hierarchical rhythms direct attention to metrically strong times during engaged listening. The N1 effect was observed only on fast tempo trials, suggesting that listeners more consistently invoke selective processing based on hierarchical rhythms when sounds are presented rapidly. The N1 effect was not modulated by musical expertise, indicating that the allocation of attention to metrically strong times is not dependent on extensive training. Additionally, changes in P2 amplitude and a late negativity were associated with metric strength under some conditions, indicating that multiple cognitive processes are associated with metric perception. PMID:26284995

  19. Components of attention modulated by temporal expectation.

    PubMed

    Sørensen, Thomas Alrik; Vangkilde, Signe; Bundesen, Claus

    2015-01-01

    By varying the probabilities that a stimulus would appear at particular times after the presentation of a cue and modeling the data by the theory of visual attention (Bundesen, 1990), Vangkilde, Coull, and Bundesen (2012) provided evidence that the speed of encoding a singly presented stimulus letter into visual short-term memory (VSTM) is modulated by the observer's temporal expectations. We extended the investigation from single-stimulus recognition to whole report (Experiment 1) and partial report (Experiment 2). Cue-stimulus foreperiods were distributed geometrically using time steps of 500 ms. In high expectancy conditions, the probability that the stimulus would appear on the next time step, given that it had not yet appeared, was high, whereas in low expectancy conditions, the probability was low. The speed of encoding the stimuli into VSTM was higher in the high expectancy conditions. In line with the Easterbrook (1959) hypothesis, under high temporal expectancy, the processing was also more focused (selective). First, the storage capacity of VSTM was lower, so that fewer stimuli were encoded into VSTM. Second, the distribution of attentional weights across stimuli was less even: The efficiency of selecting targets rather than distractors for encoding into VSTM was higher, as was the spread of the attentional weights of the target letters.

  20. Components of attention modulated by temporal expectation.

    PubMed

    Sørensen, Thomas Alrik; Vangkilde, Signe; Bundesen, Claus

    2015-01-01

    By varying the probabilities that a stimulus would appear at particular times after the presentation of a cue and modeling the data by the theory of visual attention (Bundesen, 1990), Vangkilde, Coull, and Bundesen (2012) provided evidence that the speed of encoding a singly presented stimulus letter into visual short-term memory (VSTM) is modulated by the observer's temporal expectations. We extended the investigation from single-stimulus recognition to whole report (Experiment 1) and partial report (Experiment 2). Cue-stimulus foreperiods were distributed geometrically using time steps of 500 ms. In high expectancy conditions, the probability that the stimulus would appear on the next time step, given that it had not yet appeared, was high, whereas in low expectancy conditions, the probability was low. The speed of encoding the stimuli into VSTM was higher in the high expectancy conditions. In line with the Easterbrook (1959) hypothesis, under high temporal expectancy, the processing was also more focused (selective). First, the storage capacity of VSTM was lower, so that fewer stimuli were encoded into VSTM. Second, the distribution of attentional weights across stimuli was less even: The efficiency of selecting targets rather than distractors for encoding into VSTM was higher, as was the spread of the attentional weights of the target letters. PMID:25068851

  1. Attention and prediction in human audition: a lesson from cognitive psychophysiology

    PubMed Central

    Schröger, Erich; Marzecová, Anna; SanMiguel, Iria

    2015-01-01

    Attention is a hypothetical mechanism in the service of perception that facilitates the processing of relevant information and inhibits the processing of irrelevant information. Prediction is a hypothetical mechanism in the service of perception that considers prior information when interpreting the sensorial input. Although both (attention and prediction) aid perception, they are rarely considered together. Auditory attention typically yields enhanced brain activity, whereas auditory prediction often results in attenuated brain responses. However, when strongly predicted sounds are omitted, brain responses to silence resemble those elicited by sounds. Studies jointly investigating attention and prediction revealed that these different mechanisms may interact, e.g. attention may magnify the processing differences between predicted and unpredicted sounds. Following the predictive coding theory, we suggest that prediction relates to predictions sent down from predictive models housed in higher levels of the processing hierarchy to lower levels and attention refers to gain modulation of the prediction error signal sent up to the higher level. As predictions encode contents and confidence in the sensory data, and as gain can be modulated by the intention of the listener and by the predictability of the input, various possibilities for interactions between attention and prediction can be unfolded. From this perspective, the traditional distinction between bottom-up/exogenous and top-down/endogenous driven attention can be revisited and the classic concepts of attentional gain and attentional trace can be integrated. PMID:25728182

  2. Reward valence modulates conflict-driven attentional adaptation: electrophysiological evidence.

    PubMed

    van Steenbergen, Henk; Band, Guido P H; Hommel, Bernhard

    2012-07-01

    Recent findings suggest that, relative to negative feedback, positive feedback counteracts conflict processing and subsequent attentional adaptation. Here we hypothesize that this interaction may direct adjustments in perception and action via the anterior cingulate cortex (ACC). We recorded EEG while participants performed an arrow flanker task with monetary gain or loss as arbitrary reward feedback between trials. As predicted, we found a reduction in conflict-driven adaptation for trials in which conflict was followed by monetary gain (vs. monetary loss), a behavioral effect accompanied by a modulation in early visual processing related to the processing of the distracters. Moreover, time-frequency analyses showed that ongoing fronto-central theta oscillations induced by previous conflict sustained longer after loss than after gain, an interaction presumably reflecting ACC modulation. These data provide a first important step toward understanding the neural mechanism underlying the affective regulation of conflict-driven behavior.

  3. Reward valence modulates conflict-driven attentional adaptation: electrophysiological evidence.

    PubMed

    van Steenbergen, Henk; Band, Guido P H; Hommel, Bernhard

    2012-07-01

    Recent findings suggest that, relative to negative feedback, positive feedback counteracts conflict processing and subsequent attentional adaptation. Here we hypothesize that this interaction may direct adjustments in perception and action via the anterior cingulate cortex (ACC). We recorded EEG while participants performed an arrow flanker task with monetary gain or loss as arbitrary reward feedback between trials. As predicted, we found a reduction in conflict-driven adaptation for trials in which conflict was followed by monetary gain (vs. monetary loss), a behavioral effect accompanied by a modulation in early visual processing related to the processing of the distracters. Moreover, time-frequency analyses showed that ongoing fronto-central theta oscillations induced by previous conflict sustained longer after loss than after gain, an interaction presumably reflecting ACC modulation. These data provide a first important step toward understanding the neural mechanism underlying the affective regulation of conflict-driven behavior. PMID:22504294

  4. Components of Attention Modulated by Temporal Expectation

    ERIC Educational Resources Information Center

    Sørensen, Thomas Alrik; Vangkilde, Signe; Bundesen, Claus

    2015-01-01

    By varying the probabilities that a stimulus would appear at particular times after the presentation of a cue and modeling the data by the theory of visual attention (Bundesen, 1990), Vangkilde, Coull, and Bundesen (2012) provided evidence that the speed of encoding a singly presented stimulus letter into visual short-term memory (VSTM) is…

  5. Attentional Modulation of the Mere Exposure Effect

    ERIC Educational Resources Information Center

    Yagi, Yoshihiko; Ikoma, Shinobu; Kikuchi, Tadashi

    2009-01-01

    The "mere exposure effect" refers to the phenomenon where previous exposures to stimuli increase participants' subsequent affective preference for those stimuli. This study explored the effect of selective attention on the mere exposure effect. The experiments manipulated the to-be-attended drawings in the exposure period (either red or green…

  6. Feature-based attention modulates surround suppression.

    PubMed

    Flevaris, Anastasia V; Murray, Scott O

    2015-01-28

    Stimuli appearing in the surround of the classical receptive field (CRF) can reduce neuronal firing and perceived contrast of a preferred stimulus in the CRF, a phenomenon referred to as surround suppression. Suppression is greatest when the surrounding stimulus has the same orientation and spatial frequency (SF) as the central target. Although spatial attention has been shown to influence surround suppression, the effects of feature-based attention have yet to be characterized. Using behavioral contrast adaptation in humans, we examined center-surround interactions between SF and orientation, and asked whether attending to one feature dimension versus the other influenced suppression. A center-surround triplet comprised of a central target Gabor and two flanking Gabors were used for adaptation. The flankers could have the same SF and orientation as the target, or differ in one or both of the feature dimensions. Contrast thresholds were measured for the target before and after adapting to center-surround triplets, and postadaptation thresholds were taken as an indirect measure of surround suppression. Both feature dimensions contributed to surround suppression and did not summate. Moreover, when center and surround had the same feature value in one dimension (e.g., same orientation) but had different values in the other dimension (e.g., different SF), there was more suppression when attention was directed to the feature dimension that matched between center and surround than when attention was directed to the feature dimension that differed. These results demonstrate that feature-based attention can influence center-surround interactions by enhancing the effects of the attended dimension.

  7. Attentional Modulation of Emotional Conflict Processing with Flanker Tasks

    PubMed Central

    Zhou, Pingyan; Liu, Xun

    2013-01-01

    Emotion processing has been shown to acquire priority by biasing allocation of attentional resources. Aversive images or fearful expressions are processed quickly and automatically. Many existing findings suggested that processing of emotional information was pre-attentive, largely immune from attentional control. Other studies argued that attention gated the processing of emotion. To tackle this controversy, the current study examined whether and to what degrees attention modulated processing of emotion using a stimulus-response-compatibility (SRC) paradigm. We conducted two flanker experiments using color scale faces in neutral expressions or gray scale faces in emotional expressions. We found SRC effects for all three dimensions (color, gender, and emotion) and SRC effects were larger when the conflicts were task relevant than when they were task irrelevant, suggesting that conflict processing of emotion was modulated by attention, similar to those of color and face identity (gender). However, task modulation on color SRC effect was significantly greater than that on gender or emotion SRC effect, indicating that processing of salient information was modulated by attention to a lesser degree than processing of non-emotional stimuli. We proposed that emotion processing can be influenced by attentional control, but at the same time salience of emotional information may bias toward bottom-up processing, rendering less top-down modulation than that on non-emotional stimuli. PMID:23544155

  8. Target Predictability, Sustained Attention, and Response Inhibition

    ERIC Educational Resources Information Center

    Carter, Leonie; Russell, Paul N.; Helton, William S.

    2013-01-01

    We examined whether the sustained attention to response task is a better measure of response inhibition or sustained attention. Participants performed a number detection task for 37.3 min using either a Sustained Attention to Response Task (SART; high Go low No-Go) or a more traditionally formatted vigilance task (TFT; high No-Go low Go) response…

  9. Attentional modulation of reward processing in the human brain.

    PubMed

    Rothkirch, Marcus; Schmack, Katharina; Deserno, Lorenz; Darmohray, Dana; Sterzer, Philipp

    2014-07-01

    Although neural signals of reward anticipation have been studied extensively, the functional relationship between reward and attention has remained unclear: Neural signals implicated in reward processing could either reflect attentional biases towards motivationally salient stimuli, or proceed independently of attentional processes. Here, we sought to disentangle reward and attention-related neural processes by independently modulating reward value and attentional task demands in a functional magnetic resonance imaging study in healthy human participants. During presentation of a visual reward cue that indicated whether monetary reward could be obtained in a subsequent reaction time task, participants either attended to the reward cue or performed an unrelated attention-demanding task at two different levels of difficulty. In ventral striatum and ventral tegmental area, neural responses were modulated by reward anticipation irrespective of attentional demands, thus indicating attention-independent processing of reward cues. By contrast, additive effects of reward and attention were observed in visual cortex. Critically, reward-related activations in right anterior insula strongly depended on attention to the reward cue. Dynamic causal modelling revealed that the attentional modulation of reward processing in insular cortex was mediated by enhanced effective connectivity from ventral striatum to anterior insula. Our results provide evidence for distinct functional roles of the brain regions involved in the processing of reward-indicating information: While subcortical structures signal the motivational salience of reward cues even when attention is fully engaged elsewhere, reward-related responses in anterior insula depend on available attentional resources, likely reflecting the conscious evaluation of sensory information with respect to motivational value. PMID:24307490

  10. Attentional Modulation and Selection – An Integrated Approach

    PubMed Central

    Rothenstein, Albert L.; Tsotsos, John K.

    2014-01-01

    Various models of the neural mechanisms of attentional modulation in the visual cortex have been proposed. In general, these models assume that an ‘attention’ parameter is provided separately. Its value as well as the selection of neuron(s) to which it applies are assumed, but its source and the selection mechanism are unspecified. Here we show how the Selective Tuning model of visual attention can account for the modulation of the firing rate at the single neuron level, and for the temporal pattern of attentional modulations in the visual cortex, in a self-contained formulation that simultaneously determines the stimulus elements to be attended while modulating the relevant neural processes. PMID:24963827

  11. Pharmacological interventions to modulate attentional bias in addiction.

    PubMed

    Luijten, Maartje; Field, Matt; Franken, Ingmar H A

    2014-06-01

    Attentional bias in substance-dependent patients is the tendency to automatically direct attention to substance-related cues in the environment. Preclinical models suggest that attentional bias emerges as a consequence of dopaminergic activity evoked by substance-related cues. The aim of the current review is to describe pharmacological mechanisms underlying attentional bias in humans and to critically review empirical studies that aimed to modulate attentional bias in substance-dependent patients by using pharmacological agents. The findings of the reviewed studies suggest that attentional bias and related brain activation may be modulated by dopamine. All of the reviewed studies investigated acute effects of pharmacological agents, while measurements of chronic pharmacological treatments on attentional bias and clinically relevant measures such as relapse are yet lacking. Therefore, the current findings should be interpreted as a proof of principle concerning the role of dopamine in attentional bias. At the moment, there is too little evidence for clinical applications. While the literature search was not limited to dopamine, there is a lack of studies investigating the role of non-dopaminergic neurotransmitter systems in substance-related attentional bias. A focus on neurotransmitter systems such as acetylcholine and noradrenaline could provide new insights regarding the pharmacology of substance-related attentional bias.

  12. Degraded attentional modulation of cortical neural populations in strabismic amblyopia

    PubMed Central

    Hou, Chuan; Kim, Yee-Joon; Lai, Xin Jie; Verghese, Preeti

    2016-01-01

    Behavioral studies have reported reduced spatial attention in amblyopia, a developmental disorder of spatial vision. However, the neural populations in the visual cortex linked with these behavioral spatial attention deficits have not been identified. Here, we use functional MRI–informed electroencephalography source imaging to measure the effect of attention on neural population activity in the visual cortex of human adult strabismic amblyopes who were stereoblind. We show that compared with controls, the modulatory effects of selective visual attention on the input from the amblyopic eye are substantially reduced in the primary visual cortex (V1) as well as in extrastriate visual areas hV4 and hMT+. Degraded attentional modulation is also found in the normal-acuity fellow eye in areas hV4 and hMT+ but not in V1. These results provide electrophysiological evidence that abnormal binocular input during a developmental critical period may impact cortical connections between the visual cortex and higher level cortices beyond the known amblyopic losses in V1 and V2, suggesting that a deficit of attentional modulation in the visual cortex is an important component of the functional impairment in amblyopia. Furthermore, we find that degraded attentional modulation in V1 is correlated with the magnitude of interocular suppression and the depth of amblyopia. These results support the view that the visual suppression often seen in strabismic amblyopia might be a form of attentional neglect of the visual input to the amblyopic eye. PMID:26885628

  13. Cue contrast modulates the effects of exogenous attention on appearance.

    PubMed

    Fuller, Stuart; Park, Yunsoo; Carrasco, Marisa

    2009-07-01

    Exogenous spatial attention can be automatically engaged by a cue presented in the visual periphery. To investigate the effects of exogenous attention, previous studies have generally used highly salient cues that reliably trigger attention. However, the cueing threshold of exogenous attention has been unexamined. We investigated whether the attentional effect varies with cue salience. We examined the magnitude of the attentional effect on apparent contrast [Carrasco, M., Ling, S., & Read, S. (2004). Attention alters appearance. Nature Neuroscience, 7(3), 308-313.] elicited by cues with negative Weber contrast between 6% and 100%. Cue contrast modulated the attentional effect, even at cue contrasts above the level at which observers can perfectly localize the cue; hence, the result is not due to an increase in cue visibility. No attentional effect is observed when the 100% contrast cue is presented after the stimuli, ruling out cue bias or sensory interaction between cues and stimuli as alternative explanations. A second experiment, using the same paradigm with high contrast motion stimuli gave similar results, providing further evidence against a sensory interaction explanation, as the stimuli and task were defined on a visual dimension independent from cue contrast. Although exogenous attention is triggered automatically and involuntarily, the attentional effect is gradual.

  14. Deficient attention modulation of lateralized alpha power in schizophrenia.

    PubMed

    Kustermann, Thomas; Rockstroh, Brigitte; Kienle, Johanna; Miller, Gregory A; Popov, Tzvetan

    2016-06-01

    Modulation of 8-14 Hz (alpha) activity in posterior brain regions is associated with covert attention deployment in visuospatial tasks. Alpha power decrease contralateral to to-be-attended stimuli is believed to foster subsequent processing, such as retention of task-relevant input. Degradation of this alpha-regulation mechanism may reflect an early stage of disturbed attention regulation contributing to impaired attention and working memory commonly found in schizophrenia. The present study tested this hypothesis of early disturbed attention regulation by examining alpha power modulation in a lateralized cued delayed response task in 14 schizophrenia patients (SZ) and 25 healthy controls (HC). Participants were instructed to remember the location of a 100-ms saccade-target cue in the left or right visual hemifield in order to perform a delayed saccade to that location after a retention interval. As expected, alpha power decrease during the retention interval was larger in contralateral than ipsilateral posterior regions, and SZ showed less of this lateralization than did HC. In particular, SZ failed to show hemifield-specific alpha modulation in posterior right hemisphere. Results suggest less efficient modulation of alpha oscillations that are considered critical for attention deployment and item encoding and, hence, may affect subsequent spatial working memory performance.

  15. Sustained Attention at Age 5 Predicts Attention-Related Problems at Age 9

    ERIC Educational Resources Information Center

    Martin, Anne; Razza, Rachel A.; Brooks-Gunn, Jeanne

    2012-01-01

    This study tested whether two aspects of sustained attention (focused attention and lack of impulsivity) measured at child age 5 predicted attention problems reported by mothers and teachers at age 9. Because lack of impulsivity reflects the executive control network, and ADHD is commonly characterized as a deficit in executive function, it was…

  16. Attentional Modulation of Perceptual Comparison for Feature Binding

    ERIC Educational Resources Information Center

    Kuo, Bo-Cheng; Rotshtein, Pia; Yeh, Yei-Yu

    2011-01-01

    We investigated the neural correlates of attentional modulation in the perceptual comparison process for detecting feature-binding changes in an event-related functional magnetic resonance imaging (fMRI) experiment. Participants performed a variant of a cued change detection task. They viewed a memory array, a spatial retro-cue, and later a probe…

  17. Infant Attention to Intentional Action Predicts Preschool Theory of Mind

    ERIC Educational Resources Information Center

    Wellman, Henry M.; Lopez-Duran, Sarah; LaBounty, Jennifer; Hamilton, Betsy

    2008-01-01

    This research examines whether there are continuities between infant social attention and later theory of mind. Forty-five children were studied as infants and then again as 4-year-olds. Measures of infant social attention (decrement of attention during habituation to displays of intentional action) significantly predicted later theory of mind…

  18. Object file continuity predicts attentional blink magnitude.

    PubMed

    Kellie, Frances J; Shapiro, Kimron L

    2004-05-01

    When asked to identify targets embedded within a rapid consecutive stream of visual stimuli, observers are less able to identify the second target (T2) when it is presented within half a second of the first (T1); this deficit has been termed the attentional blink (AB). Rapid serial visual presentation methodology was used to investigate the relationship between the AB and object files (episodic representations implicated in object identification and perceptual constancy). An inverse linear relationship was found between the degree of object file continuity and AB magnitude. An important locus of object file continuity was the intervening stream items between T1 and T2. The results are discussed in terms of the heuristic of the object file to preserve limited attentional capacity.

  19. Attentional bias toward safety predicts safety behaviors.

    PubMed

    Xu, Yaoshan; Li, Yongjuan; Wang, Guangxi; Yuan, Xiao; Ding, Weidong; Shen, Zhongxiang

    2014-10-01

    Safety studies have primarily focused on how explicit processes and measures affect safety behavior and subsequent accidents and injuries. Recently, safety researchers have paid greater attention to the role of implicit processes. Our research focuses on the role of attentional bias toward safety (ABS) in workplace safety. ABS is a basic, early-stage cognitive process involving the automatic and selective allocation of attentional resources toward safety cues, which reflect the implicit motivational state of employees regarding safety goal. In this study, we used two reaction time-based paradigms to measure the ABS of employees in three studies: two modified Stroop tasks (Studies 1 and 2) and a visual dot-probe task (Study 3). Results revealed that employees with better safety behavior showed significant ABS (Study 2), and greater ABS than employees with poorer safety behavior (Studies 1 and 2). Moreover, ABS was positively associated with the perceived safety climate and safety motivation of employees, both of which mediate the effect of ABS on safety behavior (Study 3). These results contributed to a deeper understanding of how early-stage automatic perceptual processing affects safety behavior. The practical implications of these results were also discussed. PMID:24922613

  20. Attentional bias toward safety predicts safety behaviors.

    PubMed

    Xu, Yaoshan; Li, Yongjuan; Wang, Guangxi; Yuan, Xiao; Ding, Weidong; Shen, Zhongxiang

    2014-10-01

    Safety studies have primarily focused on how explicit processes and measures affect safety behavior and subsequent accidents and injuries. Recently, safety researchers have paid greater attention to the role of implicit processes. Our research focuses on the role of attentional bias toward safety (ABS) in workplace safety. ABS is a basic, early-stage cognitive process involving the automatic and selective allocation of attentional resources toward safety cues, which reflect the implicit motivational state of employees regarding safety goal. In this study, we used two reaction time-based paradigms to measure the ABS of employees in three studies: two modified Stroop tasks (Studies 1 and 2) and a visual dot-probe task (Study 3). Results revealed that employees with better safety behavior showed significant ABS (Study 2), and greater ABS than employees with poorer safety behavior (Studies 1 and 2). Moreover, ABS was positively associated with the perceived safety climate and safety motivation of employees, both of which mediate the effect of ABS on safety behavior (Study 3). These results contributed to a deeper understanding of how early-stage automatic perceptual processing affects safety behavior. The practical implications of these results were also discussed.

  1. Top-down modulation: Bridging selective attention and working memory

    PubMed Central

    Gazzaley, Adam; Nobre, Anna C.

    2012-01-01

    Selective attention, the ability to focus our cognitive resources on information relevant to our goals, influences working memory (WM) performance. Indeed, attention and working memory are increasingly viewed as overlapping constructs. Here, we review recent evidence from human neurophysiological studies demonstrating that top-down modulation serves as a common neural mechanism underlying these two cognitive operations. The core features include activity modulation in stimulus-selective sensory cortices with concurrent engagement of prefrontal and parietal control regions that function as sources of top-down signals. Notably, top-down modulation is engaged during both stimulus-present and stimulus-absent stages of WM tasks, i.e., expectation of an ensuing stimulus to be remembered, selection and encoding of stimuli, maintenance of relevant information in mind and memory retrieval. PMID:22209601

  2. Distribution of attention modulates salience signals in early visual cortex.

    PubMed

    Mulckhuyse, Manon; Belopolsky, Artem V; Heslenfeld, Dirk; Talsma, Durk; Theeuwes, Jan

    2011-01-01

    Previous research has shown that the extent to which people spread attention across the visual field plays a crucial role in visual selection and the occurrence of bottom-up driven attentional capture. Consistent with previous findings, we show that when attention was diffusely distributed across the visual field while searching for a shape singleton, an irrelevant salient color singleton captured attention. However, while using the very same displays and task, no capture was observed when observers initially focused their attention at the center of the display. Using event-related fMRI, we examined the modulation of retinotopic activity related to attentional capture in early visual areas. Because the sensory display characteristics were identical in both conditions, we were able to isolate the brain activity associated with exogenous attentional capture. The results show that spreading of attention leads to increased bottom-up exogenous capture and increased activity in visual area V3 but not in V2 and V1. PMID:21637812

  3. An Evaluation of the Response Modulation Hypothesis in Relation to Attention-Deficit/ Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Farmer, Richard F.; Rucklidge, Julia J.

    2006-01-01

    Several hypotheses related to Newman's (e.g., Patterson & Newman, 1993) response modulation hypothesis were examined among adolescents with attention-deficit/hyperactivity disorder (ADHD; n = 18) and normal controls (n = 23). Consistent with predictions, youth with ADHD committed more passive avoidance errors (PAEs) than controls during the latter…

  4. Action semantics modulate action prediction.

    PubMed

    Springer, Anne; Prinz, Wolfgang

    2010-11-01

    Previous studies have demonstrated that action prediction involves an internal action simulation that runs time-locked to the real action. The present study replicates and extends these findings by indicating a real-time simulation process (Graf et al., 2007), which can be differentiated from a similarity-based evaluation of internal action representations. Moreover, results showed that action semantics modulate action prediction accuracy. The semantic effect was specified by the processing of action verbs and concrete nouns (Experiment 1) and, more specifically, by the dynamics described by action verbs (Experiment 2) and the speed described by the verbs (e.g., "to catch" vs. "to grasp" vs. "to stretch"; Experiment 3). These results propose a linkage between action simulation and action semantics as two yet unrelated domains, a view that coincides with a recent notion of a close link between motor processes and the understanding of action language.

  5. Strategic allocation of attention reduces temporally predictable stimulus conflict

    PubMed Central

    Appelbaum, L. Gregory; Boehler, Carsten N.; Won, Robert; Davis, Lauren; Woldorff, Marty G.

    2013-01-01

    Humans are able to continuously monitor environmental situations and adjust their behavioral strategies to optimize performance. Here we investigate the behavioral and brain adjustments that occur when conflicting stimulus elements are, or are not, temporally predictable. Event-related potentials (ERPs) were collected while manual-response variants of the Stroop task were performed in which the stimulus onset asynchronies (SOAs) between the relevant-color and irrelevant-word stimulus components were either randomly intermixed, or held constant, within each experimental run. Results indicated that the size of both the neural and behavioral effects of stimulus incongruency varied with the temporal arrangement of the stimulus components, such that the random-SOA arrangements produced the greatest incongruency effects at the earliest irrelevant-first SOA (−200 ms) and the constant-SOA arrangements produced the greatest effects with simultaneous presentation. These differences in conflict processing were accompanied by rapid (~150 ms) modulations of the sensory ERPs to the irrelevant distracter components when they occurred consistently first. These effects suggest that individuals are able to strategically allocate attention in time to mitigate the influence of a temporally predictable distracter. As these adjustments are instantiated by the subjects without instruction, they reveal a form of rapid strategic learning for dealing with temporally predictable stimulus incongruency. PMID:22360623

  6. Infants use attention but not emotions to predict others' actions.

    PubMed

    Vaish, Amrisha; Woodward, Amanda

    2010-02-01

    Phillips et al. (2002) suggest that by 12-14 months, infants can use a person's emotional and attentional cues to predict that person's actions. However, this work was conducted using only positive emotions, which is problematic because attention and positive emotions lead to the same prediction about a person's actions, thus leaving unclear whether infants made predictions based upon attention and emotion or attention alone. To get around this problem, we used both positive and negative emotions in a looking-time paradigm to investigate whether 14-month-old infants can use emotional cues to predict a person's actions. The findings suggest that infants used attentional but not emotional cues as predictors. We argue that while 14-month-olds can use another person's emotion cues to modify their own behavior (as in social referencing situations), they do not yet use them robustly to predict the other's behavior.

  7. Sustained Attention at Age 5 Predicts Attention-Related Problems at Age 9

    PubMed Central

    Martin, Anne; Razza, Rachel; Brooks-Gunn, Jeanne

    2012-01-01

    This study tested whether two aspects of sustained attention (focused attention and lack of impulsivity) measured at child age 5 predicted attention problems reported by mothers and teachers at age 9. Because lack of impulsivity reflects the executive control network, and ADHD is commonly characterized as a deficit in executive function, it was expected to have more predictive power than focused attention. Data were drawn from the Fragile Families and Child Wellbeing Study. Focused attention and lack of impulsivity, measured in a laboratory task at age 5, were equally predictive of attention problems at age 9, including the mother’s report of whether the child had been diagnosed with ADHD. However, age 9 teacher-reported hyperactivity was not predicted by focused attention, and only marginally predicted by lack of impulsivity. Results complement an earlier study showing that both focused attention and lack of impulsivity at age 5 predicted children’s approaches to learning at age 9 (Razza, Martin, & Brooks-Gunn, 2011). PMID:23226909

  8. Anxiety modulates the degree of attentive resources required to process emotional faces.

    PubMed

    Fox, Elaine; Russo, Riccardo; Georgiou, George A

    2005-12-01

    The present study contributes to the ongoing debate over the extent to which attentive resources are required for emotion perception. Although fearful facial expressions are strong competitors for attention, we predict that the magnitude of this effect may be modulated by anxiety. To test this hypothesis, healthy volunteers who varied in their self-reported levels of trait and state anxiety underwent an attentional blink task. Both fearful and happy facial expressions were subject to a strong attentional blink effect for low-anxious individuals. For those reporting high anxiety, a blink occurred for both fearful and happy facial expressions, but the magnitude of the attentional blink was significantly reduced for the fearful expressions. This supports the proposals that emotion perception is not fully automatic and that anxiety is related to a reduced ability to inhibit the processing of threat-related stimuli. Thus, individual differences in self-reported anxiety are an important determinant of the attentional control of emotional processing.

  9. The Interplay of Attention and Emotion: Top-down Attention Modulates Amygdala Activation in Psychopathy

    PubMed Central

    Larson, Christine L.; Baskin-Sommers, Arielle R.; Stout, Daniel M.; Balderston, Nicholas L.; Curtin, John J.; Schultz, Douglas H.; Kiehl, Kent A.; Newman, Joseph P.

    2013-01-01

    Psychopathic behavior has long been attributed to a fundamental deficit in fear that arises from impaired amygdala function. Growing evidence demonstrates that fear potentiated startle (FPS) and other psychopathy-related deficits are moderated by focus of attention but, to date, no work on adult psychopathy has examined attentional modulation of the amygdala, or concomitant recruitment of relevant attention-related circuitry. Consistent with previous FPS findings, here we report that psychopathy-related differences in amygdala activation appear and disappear as a function of goal-directed attention. Specifically, decreased amygdala activity was observed in psychopathic offenders only when attention was engaged in an alternative goal-relevant task prior to presenting threat-relevant information. Under this condition, psychopaths also exhibited greater activation in selective attention regions of the lateral prefrontal cortex (LPFC) than non-psychopaths, and this increased LPFC activation mediated psychopathy’s association with decreased amygdala activation. In contrast, when explicitly attending to threat, amygdala activation in psychopaths did not differ from non-psychopaths. This pattern of amygdala activation highlights the potential role of LPFC in mediating the failure of psychopathic individuals to process fear and other important information when it is peripheral to the primary focus of goal-directed attention. PMID:23712665

  10. Object-based attentional selection modulates anticipatory alpha oscillations.

    PubMed

    Knakker, Balázs; Weiss, Béla; Vidnyánszky, Zoltán

    2014-01-01

    Visual cortical alpha oscillations are involved in attentional gating of incoming visual information. It has been shown that spatial and feature-based attentional selection result in increased alpha oscillations over the cortical regions representing sensory input originating from the unattended visual field and task-irrelevant visual features, respectively. However, whether attentional gating in the case of object based selection is also associated with alpha oscillations has not been investigated before. Here we measured anticipatory electroencephalography (EEG) alpha oscillations while participants were cued to attend to foveal face or word stimuli, the processing of which is known to have right and left hemispheric lateralization, respectively. The results revealed that in the case of simultaneously displayed, overlapping face and word stimuli, attending to the words led to increased power of parieto-occipital alpha oscillations over the right hemisphere as compared to when faces were attended. This object category-specific modulation of the hemispheric lateralization of anticipatory alpha oscillations was maintained during sustained attentional selection of sequentially presented face and word stimuli. These results imply that in the case of object-based attentional selection-similarly to spatial and feature-based attention-gating of visual information processing might involve visual cortical alpha oscillations.

  11. Surprise? Early visual novelty processing is not modulated by attention

    PubMed Central

    Tarbi, Elise C.; Sun, Xue; Holcomb, Phillip J.; Daffner, Kirk R.

    2010-01-01

    This study investigated the influence of direction of attention on the early detection of visual novelty, as indexed by the anterior N2. The anterior N2 was measured in young subjects (n=32) under an Attend and Ignore condition. Subjects were presented standard, target/rare, and perceptually novel visual stimuli under both conditions, but under the Ignore condition, attention was directed towards an auditory n-back task. The size of the anterior N2 to novel stimuli did not differ between conditions and was significantly larger than the anterior N2 to all other stimulus types. Furthermore, under the Ignore condition, the anterior N2 to visual novel stimuli was not affected by the level of difficulty of the auditory n-back task (3-back vs. 2-back). Our findings suggest that the early processing of visual novelty, as measured by the size of the anterior N2, is not strongly modulated by direction of attention. PMID:20880260

  12. Foundational tuning: how infants' attention to speech predicts language development.

    PubMed

    Vouloumanos, Athena; Curtin, Suzanne

    2014-01-01

    Orienting biases for speech may provide a foundation for language development. Although human infants show a bias for listening to speech from birth, the relation of a speech bias to later language development has not been established. Here, we examine whether infants' attention to speech directly predicts expressive vocabulary. Infants listened to speech or non-speech in a preferential listening procedure. Results show that infants' attention to speech at 12 months significantly predicted expressive vocabulary at 18 months, while indices of general development did not. No predictive relationships were found for infants' attention to non-speech, or overall attention to sounds, suggesting that the relationship between speech and expressive vocabulary was not a function of infants' general attentiveness. Potentially ancient evolutionary perceptual capacities such as biases for conspecific vocalizations may provide a foundation for proficiency in formal systems such language, much like the approximate number sense may provide a foundation for formal mathematics.

  13. Sustained attention and prediction: distinct brain maturation trajectories during adolescence

    PubMed Central

    Thillay, Alix; Roux, Sylvie; Gissot, Valérie; Carteau-Martin, Isabelle; Knight, Robert T.; Bonnet-Brilhault, Frédérique; Bidet-Caulet, Aurélie

    2015-01-01

    Adolescence is a key period for frontal cortex maturation necessary for the development of cognitive ability. Sustained attention and prediction are cognitive functions critical for optimizing sensory processing, and essential to efficiently adapt behaviors in an ever-changing world. The aim of the current study was to investigate the brain developmental trajectories of attentive and predictive processing through adolescence. We recorded EEG in 36 participants from the age of 12–24 years (three age groups: 12–14, 14–17, 18–24 years) to target development during early and late adolescence, and early adulthood. We chose a visual target detection task which loaded upon sustained attention, and we manipulated target predictability. Continued maturation of sustained attention after age 12 was evidenced by improved performance (hits, false alarms (FAs) and sensitivity) in a detection task, associated with a frontal shift in the scalp topographies of the Contingent Negative Variation (CNV) and P3 responses, with increasing age. No effect of age was observed on predictive processing, with all ages showing similar benefits in reaction time, increases in P3 amplitude (indexing predictive value encoding and memorization), increases in CNV amplitude (corresponding to prediction implementation) and reduction in target-P3 latency (reflecting successful prediction building and use), with increased predictive content. This suggests that adolescents extracted and used predictive information to generate predictions as well as adults. The present results show that predictive and attentive processing follow distinct brain developmental trajectories: prediction abilities seem mature by the age of 12 and sustained attention continues to improve after 12-years of age and is associated with maturational changes in the frontal cortices. PMID:26483653

  14. Endogenous attention modulates early selective attention in psychopathy: An ERP investigation.

    PubMed

    Krusemark, Elizabeth A; Kiehl, Kent A; Newman, Joseph P

    2016-10-01

    Psychopathic individuals are prone to act on urges without adequate consideration of future consequences or the rights of other individuals. One interpretation of this behavior is that it reflects abnormal selective attention (i.e., a failure to process information that is incongruent with their primary focus of attention; Hiatt, Schmitt, & Newman, Neuropsychology, 18, 50-59, 2004). Unfortunately, it is unclear whether this selective attention abnormality reflects top-down endogenous influences, such as the strength or specificity of attention focus (i.e., top-down set) apart from other, more exogenous (bottom-up), effects on attention. To explore this question, we used an early visual event-related potential (N2pc) in combination with a modified visual search task designed to assess the effect of early endogenous (i.e., top-down) attention on the processing of set-congruent information. The task was administered to a sample of 70 incarcerated adult males, who were assigned to high, intermediate, and low psychopathy groups using Hare's Psychopathy Checklist-Revised (Hare, 2003). Based on the assumption that their failure to process set-incongruent information reflects the exaggerated effects of endogenous attention, we predicted that participants with high psychopathy scores would show an exaggerated N2pc response to set-congruent information. The results supported the hypothesis and provide novel electrophysiological evidence that psychopathy is associated with exaggerated endogenous attention effects during early stages of processing. Further research is needed to examine the implications of this finding for the well-established failure of psychopathic individuals to process set-incongruent information and inhibit inappropriate responses.

  15. Endogenous attention modulates early selective attention in psychopathy: An ERP investigation.

    PubMed

    Krusemark, Elizabeth A; Kiehl, Kent A; Newman, Joseph P

    2016-10-01

    Psychopathic individuals are prone to act on urges without adequate consideration of future consequences or the rights of other individuals. One interpretation of this behavior is that it reflects abnormal selective attention (i.e., a failure to process information that is incongruent with their primary focus of attention; Hiatt, Schmitt, & Newman, Neuropsychology, 18, 50-59, 2004). Unfortunately, it is unclear whether this selective attention abnormality reflects top-down endogenous influences, such as the strength or specificity of attention focus (i.e., top-down set) apart from other, more exogenous (bottom-up), effects on attention. To explore this question, we used an early visual event-related potential (N2pc) in combination with a modified visual search task designed to assess the effect of early endogenous (i.e., top-down) attention on the processing of set-congruent information. The task was administered to a sample of 70 incarcerated adult males, who were assigned to high, intermediate, and low psychopathy groups using Hare's Psychopathy Checklist-Revised (Hare, 2003). Based on the assumption that their failure to process set-incongruent information reflects the exaggerated effects of endogenous attention, we predicted that participants with high psychopathy scores would show an exaggerated N2pc response to set-congruent information. The results supported the hypothesis and provide novel electrophysiological evidence that psychopathy is associated with exaggerated endogenous attention effects during early stages of processing. Further research is needed to examine the implications of this finding for the well-established failure of psychopathic individuals to process set-incongruent information and inhibit inappropriate responses. PMID:27225501

  16. Dynamic filtering improves attentional state prediction with fNIRS.

    PubMed

    Harrivel, Angela R; Weissman, Daniel H; Noll, Douglas C; Huppert, Theodore; Peltier, Scott J

    2016-03-01

    Brain activity can predict a person's level of engagement in an attentional task. However, estimates of brain activity are often confounded by measurement artifacts and systemic physiological noise. The optimal method for filtering this noise - thereby increasing such state prediction accuracy - remains unclear. To investigate this, we asked study participants to perform an attentional task while we monitored their brain activity with functional near infrared spectroscopy (fNIRS). We observed higher state prediction accuracy when noise in the fNIRS hemoglobin [Hb] signals was filtered with a non-stationary (adaptive) model as compared to static regression (84% ± 6% versus 72% ± 15%). PMID:27231602

  17. Dynamic filtering improves attentional state prediction with fNIRS

    PubMed Central

    Harrivel, Angela R.; Weissman, Daniel H.; Noll, Douglas C.; Huppert, Theodore; Peltier, Scott J.

    2016-01-01

    Brain activity can predict a person’s level of engagement in an attentional task. However, estimates of brain activity are often confounded by measurement artifacts and systemic physiological noise. The optimal method for filtering this noise – thereby increasing such state prediction accuracy – remains unclear. To investigate this, we asked study participants to perform an attentional task while we monitored their brain activity with functional near infrared spectroscopy (fNIRS). We observed higher state prediction accuracy when noise in the fNIRS hemoglobin [Hb] signals was filtered with a non-stationary (adaptive) model as compared to static regression (84% ± 6% versus 72% ± 15%). PMID:27231602

  18. Attentional Bias towards Positive Emotion Predicts Stress Resilience.

    PubMed

    Thoern, Hanna A; Grueschow, Marcus; Ehlert, Ulrike; Ruff, Christian C; Kleim, Birgit

    2016-01-01

    There is extensive evidence for an association between an attentional bias towards emotionally negative stimuli and vulnerability to stress-related psychopathology. Less is known about whether selective attention towards emotionally positive stimuli relates to mental health and stress resilience. The current study used a modified Dot Probe task to investigate if individual differences in attentional biases towards either happy or angry emotional stimuli, or an interaction between these biases, are related to self-reported trait stress resilience. In a nonclinical sample (N = 43), we indexed attentional biases as individual differences in reaction time for stimuli preceded by either happy or angry (compared to neutral) face stimuli. Participants with greater attentional bias towards happy faces (but not angry faces) reported higher trait resilience. However, an attentional bias towards angry stimuli moderated this effect: The attentional bias towards happy faces was only predictive for resilience in those individuals who also endorsed an attentional bias towards angry stimuli. An attentional bias towards positive emotional stimuli may thus be a protective factor contributing to stress resilience, specifically in those individuals who also endorse an attentional bias towards negative emotional stimuli. Our findings therefore suggest a novel target for prevention and treatment interventions addressing stress-related psychopathology. PMID:27008475

  19. Attentional Bias towards Positive Emotion Predicts Stress Resilience.

    PubMed

    Thoern, Hanna A; Grueschow, Marcus; Ehlert, Ulrike; Ruff, Christian C; Kleim, Birgit

    2016-01-01

    There is extensive evidence for an association between an attentional bias towards emotionally negative stimuli and vulnerability to stress-related psychopathology. Less is known about whether selective attention towards emotionally positive stimuli relates to mental health and stress resilience. The current study used a modified Dot Probe task to investigate if individual differences in attentional biases towards either happy or angry emotional stimuli, or an interaction between these biases, are related to self-reported trait stress resilience. In a nonclinical sample (N = 43), we indexed attentional biases as individual differences in reaction time for stimuli preceded by either happy or angry (compared to neutral) face stimuli. Participants with greater attentional bias towards happy faces (but not angry faces) reported higher trait resilience. However, an attentional bias towards angry stimuli moderated this effect: The attentional bias towards happy faces was only predictive for resilience in those individuals who also endorsed an attentional bias towards angry stimuli. An attentional bias towards positive emotional stimuli may thus be a protective factor contributing to stress resilience, specifically in those individuals who also endorse an attentional bias towards negative emotional stimuli. Our findings therefore suggest a novel target for prevention and treatment interventions addressing stress-related psychopathology.

  20. Attentional Bias towards Positive Emotion Predicts Stress Resilience

    PubMed Central

    Ehlert, Ulrike; Ruff, Christian C.; Kleim, Birgit

    2016-01-01

    There is extensive evidence for an association between an attentional bias towards emotionally negative stimuli and vulnerability to stress-related psychopathology. Less is known about whether selective attention towards emotionally positive stimuli relates to mental health and stress resilience. The current study used a modified Dot Probe task to investigate if individual differences in attentional biases towards either happy or angry emotional stimuli, or an interaction between these biases, are related to self-reported trait stress resilience. In a nonclinical sample (N = 43), we indexed attentional biases as individual differences in reaction time for stimuli preceded by either happy or angry (compared to neutral) face stimuli. Participants with greater attentional bias towards happy faces (but not angry faces) reported higher trait resilience. However, an attentional bias towards angry stimuli moderated this effect: The attentional bias towards happy faces was only predictive for resilience in those individuals who also endorsed an attentional bias towards angry stimuli. An attentional bias towards positive emotional stimuli may thus be a protective factor contributing to stress resilience, specifically in those individuals who also endorse an attentional bias towards negative emotional stimuli. Our findings therefore suggest a novel target for prevention and treatment interventions addressing stress-related psychopathology. PMID:27008475

  1. Eye Movements during Auditory Attention Predict Individual Differences in Dorsal Attention Network Activity

    PubMed Central

    Braga, Rodrigo M.; Fu, Richard Z.; Seemungal, Barry M.; Wise, Richard J. S.; Leech, Robert

    2016-01-01

    The neural mechanisms supporting auditory attention are not fully understood. A dorsal frontoparietal network of brain regions is thought to mediate the spatial orienting of attention across all sensory modalities. Key parts of this network, the frontal eye fields (FEF) and the superior parietal lobes (SPL), contain retinotopic maps and elicit saccades when stimulated. This suggests that their recruitment during auditory attention might reflect crossmodal oculomotor processes; however this has not been confirmed experimentally. Here we investigate whether task-evoked eye movements during an auditory task can predict the magnitude of activity within the dorsal frontoparietal network. A spatial and non-spatial listening task was used with on-line eye-tracking and functional magnetic resonance imaging (fMRI). No visual stimuli or cues were used. The auditory task elicited systematic eye movements, with saccade rate and gaze position predicting attentional engagement and the cued sound location, respectively. Activity associated with these separate aspects of evoked eye-movements dissociated between the SPL and FEF. However these observed eye movements could not account for all the activation in the frontoparietal network. Our results suggest that the recruitment of the SPL and FEF during attentive listening reflects, at least partly, overt crossmodal oculomotor processes during non-visual attention. Further work is needed to establish whether the network’s remaining contribution to auditory attention is through covert crossmodal processes, or is directly involved in the manipulation of auditory information. PMID:27242465

  2. Flexible establishment of functional brain networks supports attentional modulation of unconscious cognition.

    PubMed

    Ulrich, Martin; Adams, Sarah C; Kiefer, Markus

    2014-11-01

    In classical theories of attention, unconscious automatic processes are thought to be independent of higher-level attentional influences. Here, we propose that unconscious processing depends on attentional enhancement of task-congruent processing pathways implemented by a dynamic modulation of the functional communication between brain regions. Using functional magnetic resonance imaging, we tested our model with a subliminally primed lexical decision task preceded by an induction task preparing either a semantic or a perceptual task set. Subliminal semantic priming was significantly greater after semantic compared to perceptual induction in ventral occipito-temporal (vOT) and inferior frontal cortex, brain areas known to be involved in semantic processing. The functional connectivity pattern of vOT varied depending on the induction task and successfully predicted the magnitude of behavioral and neural priming. Together, these findings support the proposal that dynamic establishment of functional networks by task sets is an important mechanism in the attentional control of unconscious processing. PMID:24954512

  3. Visual attentional capture predicts belief in a meaningful world.

    PubMed

    Bressan, Paola; Kramer, Peter; Germani, Mara

    2008-01-01

    Here we show that the automatic, involuntary process of attentional capture is predictive of beliefs that are typically considered as much more complex and higher-level. Whereas some beliefs are well supported by evidence, others, such as the belief that coincidences occur for a reason, are not. We argue that the tendency to assign meaning to coincidences is a byproduct of an adaptive system that creates and maintains cognitive schemata, and automatically directs attention to violations of a currently active schema. Earlier studies have shown that, within subjects, attentional capture increases with schema strength. Yet, between-subjects effects could exist too: whereas each of us has schemata of various strengths, most likely different individuals are differently inclined to maintain strong or weak ones. Since schemata can be interpreted as beliefs, we predict more attentional capture for subjects with stronger beliefs than for subjects with weaker ones. We measured visual attentional capture in a reaction time experiment, and correlated it with scores on questionnaires about religious and other beliefs and about meaningfulness and surprisingness of coincidences. We found that visual attentional capture predicts a belief in meaningfulness of coincidences, and that this belief mediates a relationship between visual attentional capture and religiosity. Remarkably, strong believers were more disturbed by schema violations than weak believers, and yet appeared less aware of the disrupting events. We conclude that (a) religious people have a stronger belief in meaningfulness of coincidences, indicative of a more general tendency to maintain strong schemata, and that (b) this belief leads them to suppress, ignore, or forget information that has demonstrably captured their attention, but happens to be inconsistent with their schemata.

  4. Infants' Joint Attention Skills Predict Toddlers' Emerging Mental State Language

    ERIC Educational Resources Information Center

    Kristen, Susanne; Sodian, Beate; Thoermer, Claudia; Perst, Hannah

    2011-01-01

    To assess predictive relations between joint attention skills, intention understanding, and mental state vocabulary, 88 children were tested with measures of comprehension of gaze and referential pointing, as well as the production of declarative gestures and the comprehension and production of imperative gestures, at the ages of 7-18 months.…

  5. Attention effects on vicarious modulation of nociception and pain.

    PubMed

    Khatibi, Ali; Vachon-Presseau, Etienne; Schrooten, Martien; Vlaeyen, Johan; Rainville, Pierre

    2014-10-01

    The observation of others' facial expressions of pain has been shown to facilitate the observer's nociceptive responses and to increase pain perception. We investigated how this vicarious facilitation effect is modulated by directing the observer's attention toward the meaning of pain expression or the facial movements. In separate trials, participants were instructed to assess the "intensity of the pain expression"(meaning) or to "discriminate the facial movements" in the upper vs lower part of the face shown in 1-second dynamic clips displaying mild, moderate, or strong pain expressions or a neutral control. In 50% of the trials, participants received a painful electrical stimulation to the sural nerve immediately after the presentation of the expression. Low-level nociceptive reactivity was measured with the RIII-response, and pain perception was assessed using pain ratings. Pain induced by the electrical stimulation increased after viewing stronger pain expressions in both tasks, but the RIII-response showed this vicarious facilitation effect only in the movement discrimination task at the strongest expression intensity. These findings are consistent with the notion that vicarious processes facilitate self-pain and may prime automatic nociceptive responses. However, this priming effect is influenced by top-down attentional processes. These results provide another case of dissociation between reflexive and perceptual processes, consistent with the involvement of partly separate brain networks in the regulation of cortical and lower-level nociceptive responses. Combined with previous results, these findings suggest that vicarious pain facilitation is an automatic process that may be diminished by top-down attentional processes directed at the meaning of the expression.

  6. Anxiety modulates the effects of emotion and attention on early vision.

    PubMed

    Ferneyhough, Emma; Kim, Min K; Phelps, Elizabeth A; Carrasco, Marisa

    2013-01-01

    At attended locations emotion and attention interact to benefit contrast sensitivity, a basic visual dimension. Whether there are associated costs at unattended locations is unknown. Furthermore, emotion and attention affect response time, and anxiety modulates these effects. We investigated how trait-anxiety influences the interaction of emotion and attention on contrast sensitivity. On each trial, non-predictive pre-cues (neutral or fearful faces) directed exogenous attention to four contrast-varying, tilted stimuli (Gabor patches). Attention was cued toward the target (valid), a distracter (invalid), or distributed over all locations. Observers discriminated target orientation, and completed self-report measures of anxiety. Effects of fearful expressions were mediated by trait anxiety. Only high-trait-anxious individuals showed decreased target contrast sensitivity after attention was diverted to a distracter by a fearful cue, and anxiety score correlated with degree of impairment across participants. This indicates that increasing anxiety exacerbates threat-related attentional costs to visual perception, hampering processing at non-threat-related locations. PMID:22784014

  7. The effect of modulating top-down attention deployment on the N2pc/PCN.

    PubMed

    Liu, Qiang; Lin, Shuyu; Zhao, Guang; Roberson, Debi

    2016-05-01

    The N2pc (PCN) component of the event-related potential (ERP) waveform provides a useful tool for directly assessing the locus of spatial attention in visual search. It is still unclear whether the amplitude of the N2pc/PCN relates to the deployment of attentional resources. A key issue is the lack of evidence that top-down allocation of attention affects the N2pc/PCN amplitude. Previous findings could be explained if manipulating different expectancy strategies changes participants' search mode, causing them to redefine the target's features. In this study, we explored the relationship between N2pc/PCN amplitude and top-down attention allocation by manipulating the discriminative difficulty (differences in the response-defining feature) but leaving the search difficulty (target's saliency) unchanged. Using the same sets of stimuli, in a blocked condition, participants showed the expected higher amplitude of N2pc/PCN in the hardest condition, compared to easier discrimination conditions. Importantly, there was no difference in the N2pc/PCN when the exact same stimulus sets were presented in a randomly interleaved mixed set. At a behavioral level, in both conditions performance was significantly slower for the hardest condition. This finding indicates that the N2pc/PCN component is modulated by the predictability of discriminative difficulty, which reflects the modulation of top-down attentional deployment.

  8. Attention Modulates TMS-Locked Alpha Oscillations in the Visual Cortex.

    PubMed

    Herring, Jim D; Thut, Gregor; Jensen, Ole; Bergmann, Til O

    2015-10-28

    Cortical oscillations, such as 8-12 Hz alpha-band activity, are thought to subserve gating of information processing in the human brain. While most of the supporting evidence is correlational, causal evidence comes from attempts to externally drive ("entrain") these oscillations by transcranial magnetic stimulation (TMS). Indeed, the frequency profile of TMS-evoked potentials (TEPs) closely resembles that of oscillations spontaneously emerging in the same brain region. However, it is unclear whether TMS-locked and spontaneous oscillations are produced by the same neuronal mechanisms. If so, they should react in a similar manner to top-down modulation by endogenous attention. To test this prediction, we assessed the alpha-like EEG response to TMS of the visual cortex during periods of high and low visual attention while participants attended to either the visual or auditory modality in a cross-modal attention task. We observed a TMS-locked local oscillatory alpha response lasting several cycles after TMS (but not after sham stimulation). Importantly, TMS-locked alpha power was suppressed during deployment of visual relative to auditory attention, mirroring spontaneous alpha amplitudes. In addition, the early N40 TEP component, located at the stimulation site, was amplified by visual attention. The extent of attentional modulation for both TMS-locked alpha power and N40 amplitude did depend, with opposite sign, on the individual ability to modulate spontaneous alpha power at the stimulation site. We therefore argue that TMS-locked and spontaneous oscillations are of common neurophysiological origin, whereas the N40 TEP component may serve as an index of current cortical excitability at the time of stimulation.

  9. Attention Modulates TMS-Locked Alpha Oscillations in the Visual Cortex.

    PubMed

    Herring, Jim D; Thut, Gregor; Jensen, Ole; Bergmann, Til O

    2015-10-28

    Cortical oscillations, such as 8-12 Hz alpha-band activity, are thought to subserve gating of information processing in the human brain. While most of the supporting evidence is correlational, causal evidence comes from attempts to externally drive ("entrain") these oscillations by transcranial magnetic stimulation (TMS). Indeed, the frequency profile of TMS-evoked potentials (TEPs) closely resembles that of oscillations spontaneously emerging in the same brain region. However, it is unclear whether TMS-locked and spontaneous oscillations are produced by the same neuronal mechanisms. If so, they should react in a similar manner to top-down modulation by endogenous attention. To test this prediction, we assessed the alpha-like EEG response to TMS of the visual cortex during periods of high and low visual attention while participants attended to either the visual or auditory modality in a cross-modal attention task. We observed a TMS-locked local oscillatory alpha response lasting several cycles after TMS (but not after sham stimulation). Importantly, TMS-locked alpha power was suppressed during deployment of visual relative to auditory attention, mirroring spontaneous alpha amplitudes. In addition, the early N40 TEP component, located at the stimulation site, was amplified by visual attention. The extent of attentional modulation for both TMS-locked alpha power and N40 amplitude did depend, with opposite sign, on the individual ability to modulate spontaneous alpha power at the stimulation site. We therefore argue that TMS-locked and spontaneous oscillations are of common neurophysiological origin, whereas the N40 TEP component may serve as an index of current cortical excitability at the time of stimulation. PMID:26511236

  10. Feasibility and validity of the structured attention module among economically disadvantaged preschool-age children.

    PubMed

    Bush, Hillary H; Eisenhower, Abbey; Briggs-Gowan, Margaret; Carter, Alice S

    2015-01-01

    Rooted in the theory of attention put forth by Mirsky, Anthony, Duncan, Ahearn, and Kellam (1991), the Structured Attention Module (SAM) is a developmentally sensitive, computer-based performance task designed specifically to assess sustained selective attention among 3- to 6-year-old children. The current study addressed the feasibility and validity of the SAM among 64 economically disadvantaged preschool-age children (mean age = 58 months; 55% female); a population known to be at risk for attention problems and adverse math performance outcomes. Feasibility was demonstrated by high completion rates and strong associations between SAM performance and age. Principal Factor Analysis with rotation produced robust support for a three-factor model (Accuracy, Speed, and Endurance) of SAM performance, which largely corresponded with existing theorized models of selective and sustained attention. Construct validity was evidenced by positive correlations between SAM Composite scores and all three SAM factors and IQ, and between SAM Accuracy and sequential memory. Value-added predictive validity was not confirmed through main effects of SAM on math performance above and beyond age and IQ; however, significant interactions by child sex were observed: Accuracy and Endurance both interacted with child sex to predict math performance. In both cases, the SAM factors predicted math performance more strongly for girls than for boys. There were no overall sex differences in SAM performance. In sum, the current findings suggest that interindividual variation in sustained selective attention, and potentially other aspects of attention and executive function, among young, high-risk children can be captured validly with developmentally sensitive measures.

  11. Feasibility and validity of the structured attention module among economically disadvantaged preschool-age children.

    PubMed

    Bush, Hillary H; Eisenhower, Abbey; Briggs-Gowan, Margaret; Carter, Alice S

    2015-01-01

    Rooted in the theory of attention put forth by Mirsky, Anthony, Duncan, Ahearn, and Kellam (1991), the Structured Attention Module (SAM) is a developmentally sensitive, computer-based performance task designed specifically to assess sustained selective attention among 3- to 6-year-old children. The current study addressed the feasibility and validity of the SAM among 64 economically disadvantaged preschool-age children (mean age = 58 months; 55% female); a population known to be at risk for attention problems and adverse math performance outcomes. Feasibility was demonstrated by high completion rates and strong associations between SAM performance and age. Principal Factor Analysis with rotation produced robust support for a three-factor model (Accuracy, Speed, and Endurance) of SAM performance, which largely corresponded with existing theorized models of selective and sustained attention. Construct validity was evidenced by positive correlations between SAM Composite scores and all three SAM factors and IQ, and between SAM Accuracy and sequential memory. Value-added predictive validity was not confirmed through main effects of SAM on math performance above and beyond age and IQ; however, significant interactions by child sex were observed: Accuracy and Endurance both interacted with child sex to predict math performance. In both cases, the SAM factors predicted math performance more strongly for girls than for boys. There were no overall sex differences in SAM performance. In sum, the current findings suggest that interindividual variation in sustained selective attention, and potentially other aspects of attention and executive function, among young, high-risk children can be captured validly with developmentally sensitive measures. PMID:24564761

  12. Infant attention to intentional action predicts preschool theory of mind.

    PubMed

    Wellman, Henry M; Lopez-Duran, Sarah; LaBounty, Jennifer; Hamilton, Betsy

    2008-03-01

    This research examines whether there are continuities between infant social attention and later theory of mind. Forty-five children were studied as infants and then again as 4-year-olds. Measures of infant social attention (decrement of attention during habituation to displays of intentional action) significantly predicted later theory of mind (false-belief understanding). Possibly, this longitudinal association could have been explained by more general developments in IQ, verbal competence, or executive function (rather than continuities in the realm of social cognition). However, the association remained significant and undiminished even when IQ, verbal competence, and executive function were controlled. The findings thus provide strong support for an important continuity in social cognition separable from continuities in more general information processing. PMID:18331149

  13. Impairment in Emotional Modulation of Attention and Memory in Schizophrenia

    PubMed Central

    Walsh-Messinger, Julie; Ramirez, Paul Michael; Wong, Philip; Antonius, Daniel; Aujero, Nicole; McMahon, Kevin; Opler, Lewis A.; Malaspina, Dolores

    2014-01-01

    Emotion plays a critical role in cognition and goal-directed behavior via complex interconnections between the emotional and motivational systems. It has been hypothesized that the impairment in goal-directed behavior widely noted in schizophrenia may result from defects in the interaction between the neural (ventral) emotional system and (rostral) cortical processes. The present study examined the impact of emotion on attention and memory in schizophrenia. Twenty-five individuals with schizophrenia related psychosis and 25 healthy control subjects were administered a computerized task in which they were asked to search for target images during a rapid serial visual presentation of pictures. Target stimuli were either positive, negative, or neutral images presented at either 200ms or 700ms lag. Additionally, a visual hedonics task was used to assess differences between the schizophrenia group and controls on ratings of valence and arousal from the picture stimuli. Compared to controls, individuals with schizophrenia detected fewer emotional images under both the 200ms and 700ms lag conditions. Multivariate analyses showed that the schizophrenia group also detected fewer positive images under the 700 lag condition and fewer negative images under the 200 lag condition. Individuals with schizophrenia reported higher pleasantness and unpleasantness ratings than controls in response to neutral stimuli, while controls reported higher arousal ratings for neutral and positive stimuli compared to the schizophrenia group. These results highlight dysfunction in the neural modulation of emotion, attention, and cortical processing in schizophrenia, adding to the growing but mixed body of literature on emotion processing in the disorder. PMID:24910446

  14. [Independent resource of each hemisphere modulates selective attention].

    PubMed

    Yoshizaki, Kazuhito; Nishimura, Ritsuko

    2008-06-01

    Based on the load theory and the assumption that each hemisphere has independent resources, we examined the effects of perceptual load in each hemisphere on the compatibility effect. In Experiments 1, and 2ab, two letter-strings were presented to the left and right visual-fields with a distracter, which was presented on the center of the screen. Two conditions were prepared by pairing a letter-string which contained a target with one which did not. Right-handed participants were asked to identify the target in the letter-strings while ignoring the distracter. The results showed that the compatibility effect was larger when the perceptual load of the letter-string which did not contain a target was low. This suggests that the residual resources of the hemisphere where the target was not projected facilitated the processing of the distracter. In Experiment 3, two letter-strings were presented to both hemispheres. The results showed that the compatibility effect was constant, irrespective of the perceptual load of the letter-string. Our findings suggested that selective attention is modulated by the resources of each hemisphere. PMID:18678063

  15. Silent Expectations: Dynamic Causal Modeling of Cortical Prediction and Attention to Sounds That Weren't

    PubMed Central

    Noreika, Valdas; Gueorguiev, David; Shtyrov, Yury; Bekinschtein, Tristan A.; Henson, Richard

    2016-01-01

    There is increasing evidence that human perception is realized by a hierarchy of neural processes in which predictions sent backward from higher levels result in prediction errors that are fed forward from lower levels, to update the current model of the environment. Moreover, the precision of prediction errors is thought to be modulated by attention. Much of this evidence comes from paradigms in which a stimulus differs from that predicted by the recent history of other stimuli (generating a so-called “mismatch response”). There is less evidence from situations where a prediction is not fulfilled by any sensory input (an “omission” response). This situation arguably provides a more direct measure of “top-down” predictions in the absence of confounding “bottom-up” input. We applied Dynamic Causal Modeling of evoked electromagnetic responses recorded by EEG and MEG to an auditory paradigm in which we factorially crossed the presence versus absence of “bottom-up” stimuli with the presence versus absence of “top-down” attention. Model comparison revealed that both mismatch and omission responses were mediated by increased forward and backward connections, differing primarily in the driving input. In both responses, modeling results suggested that the presence of attention selectively modulated backward “prediction” connections. Our results provide new model-driven evidence of the pure top-down prediction signal posited in theories of hierarchical perception, and highlight the role of attentional precision in strengthening this prediction. SIGNIFICANCE STATEMENT Human auditory perception is thought to be realized by a network of neurons that maintain a model of and predict future stimuli. Much of the evidence for this comes from experiments where a stimulus unexpectedly differs from previous ones, which generates a well-known “mismatch response.” But what happens when a stimulus is unexpectedly omitted altogether? By measuring the brain

  16. Electrocortical indices of selective attention predict adolescent executive functioning.

    PubMed

    Lackner, Christine L; Santesso, Diane L; Dywan, Jane; Wade, Terrance J; Segalowitz, Sidney J

    2013-05-01

    Executive functioning is considered a powerful predictor of behavioral and mental health outcomes during adolescence. Our question was whether executive functioning skills, normally considered "top-down" processes, are related to automatic aspects of selective attention. Event-related potentials (ERPs) were recorded from typically-developing 12-14-year-old adolescents as they responded to tones presented in attended and unattended channels in an auditory selective attention task. Examining these ERPs in relation to parental reports on the Behavior Rating Inventory of Executive Function (BRIEF) revealed that an early frontal positivity (EFP) elicited by to-be-ignored/unattended tones was larger in those with poorer executive functions, driven by scores on the BRIEF Metacognition Index. As is traditionally found, N1 amplitudes were more negative for the to-be-attended rather than unattended tones. Additionally, N1 latencies to unattended tones correlated with parent-ratings on the BRIEF Behavior Regulation Index, where shorter latencies predicted better executive functions. Results suggest that the ability to disengage attention from distractor information in the early stages of stimulus processing is associated with adolescent executive functioning skills. PMID:23528784

  17. Electrocortical indices of selective attention predict adolescent executive functioning.

    PubMed

    Lackner, Christine L; Santesso, Diane L; Dywan, Jane; Wade, Terrance J; Segalowitz, Sidney J

    2013-05-01

    Executive functioning is considered a powerful predictor of behavioral and mental health outcomes during adolescence. Our question was whether executive functioning skills, normally considered "top-down" processes, are related to automatic aspects of selective attention. Event-related potentials (ERPs) were recorded from typically-developing 12-14-year-old adolescents as they responded to tones presented in attended and unattended channels in an auditory selective attention task. Examining these ERPs in relation to parental reports on the Behavior Rating Inventory of Executive Function (BRIEF) revealed that an early frontal positivity (EFP) elicited by to-be-ignored/unattended tones was larger in those with poorer executive functions, driven by scores on the BRIEF Metacognition Index. As is traditionally found, N1 amplitudes were more negative for the to-be-attended rather than unattended tones. Additionally, N1 latencies to unattended tones correlated with parent-ratings on the BRIEF Behavior Regulation Index, where shorter latencies predicted better executive functions. Results suggest that the ability to disengage attention from distractor information in the early stages of stimulus processing is associated with adolescent executive functioning skills.

  18. Attention does not modulate neural responses to social stimuli in autism spectrum disorders.

    PubMed

    Bird, Geoffrey; Catmur, Caroline; Silani, Giorgia; Frith, Chris; Frith, Uta

    2006-07-15

    We investigated whether individuals with autism spectrum disorders (ASD) would show attentional modulation for social (face) and non-social (house) stimuli. Sixteen individuals with ASD and 16 matched control participants completed a task in which pairs of face and house stimuli were present on every trial, with one of the pairs randomly assigned to attended locations and the other to unattended locations. Both mass-univariate (SPM) and region of interest analyses suggested that responses to houses were modulated by attention in both groups, but that only the control participants demonstrated attentional modulation of face-selective regions. Thus, the participants with ASD demonstrated a lack of attentional modulation which was particularly evident for the social stimulus. Analyses of effective connectivity indicated that these results were due to a failure of attention to modulate connectivity between extrastriate areas and V1. We discuss how these results may suggest a mechanism to explain the reduced salience of social stimuli in ASD. PMID:16616862

  19. Context Modulates Attention to Social Scenes in Toddlers with Autism

    ERIC Educational Resources Information Center

    Chawarska, Katarzyna; Macari, Suzanne; Shic, Frederick

    2012-01-01

    Background: In typical development, the unfolding of social and communicative skills hinges upon the ability to allocate and sustain attention toward people, a skill present moments after birth. Deficits in social attention have been well documented in autism, though the underlying mechanisms are poorly understood. Methods: In order to parse the…

  20. Listeners modulate temporally selective attention during natural speech processing

    PubMed Central

    Astheimer, Lori B.; Sanders, Lisa D.

    2009-01-01

    Spatially selective attention allows for the preferential processing of relevant stimuli when more information than can be processed in detail is presented simultaneously at distinct locations. Temporally selective attention may serve a similar function during speech perception by allowing listeners to allocate attentional resources to time windows that contain highly relevant acoustic information. To test this hypothesis, event-related potentials were compared in response to attention probes presented in six conditions during a narrative: concurrently with word onsets, beginning 50 and 100 ms before and after word onsets, and at random control intervals. Times for probe presentation were selected such that the acoustic environments of the narrative were matched for all conditions. Linguistic attention probes presented at and immediately following word onsets elicited larger amplitude N1s than control probes over medial and anterior regions. These results indicate that native speakers selectively process sounds presented at specific times during normal speech perception. PMID:18395316

  1. Great expectations: top-down attention modulates the costs of clutter and eccentricity.

    PubMed

    Steelman, Kelly S; McCarley, Jason S; Wickens, Christopher D

    2013-12-01

    An experiment and modeling effort examined interactions between bottom-up and top-down attentional control in visual alert detection. Participants performed a manual tracking task while monitoring peripheral display channels for alerts of varying salience, eccentricity, and spatial expectancy. Spatial expectancy modulated the influence of salience and eccentricity; alerts in low-probability locations engendered higher miss rates, longer detection times, and larger costs of visual clutter and eccentricity, indicating that top-down attentional control offset the costs of poor bottom-up stimulus quality. Data were compared to the predictions of a computational model of scanning and noticing that incorporates bottom-up and top-down sources of attentional control. The model accounted well for the overall pattern of miss rates and response times, predicting each of the observed main effects and interactions. Empirical results suggest that designers should expect the costs of poor bottom-up visibility to be greater for low expectancy signals, and that the placement of alerts within a display should be determined based on the combination of alert expectancy and response priority. Model fits suggest that the current model can serve as a useful tool for exploring a design space as a precursor to empirical data collection and for generating hypotheses for future experiments.

  2. Attention Modulates TMS-Locked Alpha Oscillations in the Visual Cortex

    PubMed Central

    Herring, Jim D.; Thut, Gregor; Jensen, Ole

    2015-01-01

    Cortical oscillations, such as 8–12 Hz alpha-band activity, are thought to subserve gating of information processing in the human brain. While most of the supporting evidence is correlational, causal evidence comes from attempts to externally drive (“entrain”) these oscillations by transcranial magnetic stimulation (TMS). Indeed, the frequency profile of TMS-evoked potentials (TEPs) closely resembles that of oscillations spontaneously emerging in the same brain region. However, it is unclear whether TMS-locked and spontaneous oscillations are produced by the same neuronal mechanisms. If so, they should react in a similar manner to top-down modulation by endogenous attention. To test this prediction, we assessed the alpha-like EEG response to TMS of the visual cortex during periods of high and low visual attention while participants attended to either the visual or auditory modality in a cross-modal attention task. We observed a TMS-locked local oscillatory alpha response lasting several cycles after TMS (but not after sham stimulation). Importantly, TMS-locked alpha power was suppressed during deployment of visual relative to auditory attention, mirroring spontaneous alpha amplitudes. In addition, the early N40 TEP component, located at the stimulation site, was amplified by visual attention. The extent of attentional modulation for both TMS-locked alpha power and N40 amplitude did depend, with opposite sign, on the individual ability to modulate spontaneous alpha power at the stimulation site. We therefore argue that TMS-locked and spontaneous oscillations are of common neurophysiological origin, whereas the N40 TEP component may serve as an index of current cortical excitability at the time of stimulation. SIGNIFICANCE STATEMENT Rhythmic transcranial magnetic stimulation (TMS) is a promising tool to experimentally “entrain” cortical activity. If TMS-locked oscillatory responses actually recruit the same neuronal mechanisms as spontaneous cortical

  3. Threat captures attention, but not automatically: Top-down goals modulate attentional orienting to threat distractors.

    PubMed

    Vromen, Joyce M G; Lipp, Ottmar V; Remington, Roger W; Becker, Stefanie I

    2016-10-01

    The rapid orienting of attention to potential threats has been proposed to proceed outside of top-down control. However, paradigms that have been used to investigate this have struggled to separate the rapid orienting of attention (i.e. capture) from the later disengagement of focal attention that may be subject to top-down control. Consequently, it remains unclear whether and to what extent orienting to threat is contingent on top-down goals. The current study manipulated the goal-relevance of threat distractors (spiders), whilst a strict top-down attentional set was encouraged by presenting the saliently colored target and the threat distracter simultaneously for a limited time. The goal-relevance of threatening distractors was manipulated by including a spider amongst the possible target stimuli (Experiment 1: spider/cat targets) or excluding it (Experiment 2: bird/fish targets). Orienting and disengagement were disentangled by cueing attention away from or towards the threat prior to its onset. The results indicated that the threatening spider distractors elicited rapid orienting of attention when spiders were potentially goal-relevant (Experiment 1) but did so much less when they were irrelevant to the task goal (Experiment 2). Delayed disengagement from the threat distractors was even more strongly contingent on the task goal and occurred only when a spider was a possible target. These results highlight the role of top-down goals in attentional orienting to and disengagement from threat. PMID:27234013

  4. Personality and attention: Levels of neuroticism and extraversion can predict attentional performance during a change detection task.

    PubMed

    Hahn, Sowon; Buttaccio, Daniel R; Hahn, Jungwon; Lee, Taehun

    2015-01-01

    The present study demonstrates that levels of extraversion and neuroticism can predict attentional performance during a change detection task. After completing a change detection task built on the flicker paradigm, participants were assessed for personality traits using the Revised Eysenck Personality Questionnaire (EPQ-R). Multiple regression analyses revealed that higher levels of extraversion predict increased change detection accuracies, while higher levels of neuroticism predict decreased change detection accuracies. In addition, neurotic individuals exhibited decreased sensitivity A' and increased fixation dwell times. Hierarchical regression analyses further revealed that eye movement measures mediate the relationship between neuroticism and change detection accuracies. Based on the current results, we propose that neuroticism is associated with decreased attentional control over the visual field, presumably due to decreased attentional disengagement. Extraversion can predict increased attentional performance, but the effect is smaller than the relationship between neuroticism and attention.

  5. Emotion Modulation of Visual Attention: Categorical and Temporal Characteristics

    PubMed Central

    Ciesielski, Bethany G.; Armstrong, Thomas; Zald, David H.; Olatunji, Bunmi O.

    2010-01-01

    Background Experimental research has shown that emotional stimuli can either enhance or impair attentional performance. However, the relative effects of specific emotional stimuli and the specific time course of these differential effects are unclear. Methodology/Principal Findings In the present study, participants (n = 50) searched for a single target within a rapid serial visual presentation of images. Irrelevant fear, disgust, erotic or neutral images preceded the target by two, four, six, or eight items. At lag 2, erotic images induced the greatest deficits in subsequent target processing compared to other images, consistent with a large emotional attentional blink. Fear and disgust images also produced a larger attentional blinks at lag 2 than neutral images. Erotic, fear, and disgust images continued to induce greater deficits than neutral images at lag 4 and 6. However, target processing deficits induced by erotic, fear, and disgust images at intermediate lags (lag 4 and 6) did not consistently differ from each other. In contrast to performance at lag 2, 4, and 6, enhancement in target processing for emotional stimuli was observed in comparison to neutral stimuli at lag 8. Conclusions/Significance These findings suggest that task-irrelevant emotion information, particularly erotica, impairs intentional allocation of attention at early temporal stages, but at later temporal stages, emotional stimuli can have an enhancing effect on directed attention. These data suggest that the effects of emotional stimuli on attention can be both positive and negative depending upon temporal factors. PMID:21079773

  6. Temporal cuing modulates alpha oscillations during auditory attentional blink.

    PubMed

    Shen, Dawei; Ross, Bernhard; Alain, Claude

    2016-07-01

    Attentional blink (AB) refers to the phenomenon whereby the correct identification of a visual or auditory target impairs processing of a subsequent probe. Although it has been shown that knowing in advance, when the probe would be presented, reduces the attentional blink and increases the amplitude of event-related potential (ERP) elicited by the probe, the neural mechanism by which attention mitigates the AB remains unclear. Here, we used time-frequency analysis to further explore the mechanism of the auditory attentional blink. Participants were presented a series of rapid auditory stimuli and asked to indicate whether a target and a probe were present in the sequence. In half of the trials, participants were cued to the probe position relative to the target ('Early' or 'Late'). Probe detection and ERP amplitude elicited by the probe decreased when the probe was presented shortly after the target compared to when it was presented later after the target. Importantly, the behavioral and ERP correlates of probe discrimination significantly improved when the 'Early' cue was presented. The improvement in processing the probe in the cued condition was accompanied by the decrease in alpha activity (8-13 Hz) after the time when the probe was expected; suggesting that successfully directing attention to time window where the probe would likely occur reduces the processing resources needed to suppress distractors. This in turn freed up available processing resources for the target and probe at the short-term consolidation stage, which ultimately reduced the auditory attentional blink. PMID:27152668

  7. Spatiotemporal dynamics of early spatial and category-specific attentional modulations.

    PubMed

    Ioannides, Andreas A; Poghosyan, Vahe

    2012-04-15

    Different attention types select and focus brain resources on relevant sensory information. However, key questions remain unresolved: when and where cortical visual processing is first modulated by different types of attention? How do such modulatory effects spread thereafter? Here, we address these issues for spatial and category-specific types of attention using magnetoencephalography (MEG). First we identified the dynamics of visual attention-independent sensory processing to serve as a baseline framework for the attentional modulations of interest. We found that visual information is processed through the entire hierarchy of visual areas in at least two phases, in the 40-130 ms and 130-230 ms periods respectively. Spatial attention modulations were identified from the beginning of the initial stimulus-evoked response in the primary visual cortex ~70 ms post-stimulus. Category-specific attention modulated face processing beginning from the first face-specific response in high-level object-related areas ~100 ms post-stimulus, substantially earlier than previously reported for face-directed attention. Thus both attention types modulated responses during the first processing phase, beginning at the earliest brain area capable of coding the attentional target. Thereafter attentional effects propagated through the visual cortex together with the stimulus-evoked activity. Category-specific attention did not affect the first-phase responses in low-level strongly retinotopic visual areas, while the second-phase responses were enhanced when the stimulus was the response target and reduced when it was a distractor. Responses during both phases in high-level object-related areas were enhanced by category-specific attention independent of their target/distractor status. Spatial attention effects were stronger in low-level areas, whereas category-specific attention effects were stronger in high-level object-related areas. PMID:22342803

  8. Emotional prosody modulates attention in schizophrenia patients with hallucinations

    PubMed Central

    Alba-Ferrara, L.; de Erausquin, G. A.; Hirnstein, M.; Weis, S.; Hausmann, M.

    2012-01-01

    Recent findings have demonstrated that emotional prosody (EP) attracts attention involuntarily (Grandjean et al., 2008). The automat shift of attention toward emotionally salient stimuli can be overcome by attentional control (Hahn et al., 2010). Attentional control is impaired in schizophrenia, especially in schizophrenic patients with hallucinations because the “voices” capture attention increasing the processing load and competing for top-down resources. The present study investigates how involuntary attention is driven by implicit EP in schizophrenia with auditory verbal hallucinations (AVH) and without (NAVH). Fifteen AVH patients, 12 NAVH patients and 16 healthy controls (HC) completed a dual-task dichotic listening paradigm, in which an emotional vocal outburst was paired with a neutral vocalization spoken in male and female voices. Participants were asked to report the speaker's gender while attending to either the left or right ear. NAVH patients and HC revealed shorter response times for stimuli presented to the attended left ear than the attended right ear. This laterality effect was not present in AVH patients. In addition, NAVH patients and HC showed faster responses when the EP stimulus was presented to the unattended ear, probably because of less interference between the attention-controlled gender voice identification task and involuntary EP processing. AVH patients did not benefit from presenting emotional stimuli to the unattended ear. The findings suggest that similar to HC, NAVH patients show a right hemispheric bias for EP processing. AVH patients seem to be less lateralized for EP and therefore might be more susceptible to interfering involuntary EP processing; regardless which ear/hemisphere receives the bottom up input. PMID:23459397

  9. Both a nicotinic single nucleotide polymorphism (SNP) and a noradrenergic SNP modulate working memory performance when attention is manipulated.

    PubMed

    Greenwood, Pamela M; Sundararajan, Ramya; Lin, Ming-Kuan; Kumar, Reshma; Fryxell, Karl J; Parasuraman, Raja

    2009-11-01

    We investigated the relation between the two systems of visuospatial attention and working memory by examining the effect of normal variation in cholinergic and noradrenergic genes on working memory performance under attentional manipulation. We previously reported that working memory for location was impaired following large location precues, indicating the scale of visuospatial attention has a role in forming the mental representation of the target. In one of the first studies to compare effects of two single nucleotide polymorphisms (SNPs) on the same cognitive task, we investigated the neurotransmission systems underlying interactions between attention and memory. Based on our previous report that the CHRNA4 rs#1044396 C/T nicotinic receptor SNP affected visuospatial attention, but not working memory, and the DBH rs#1108580 G/A noradrenergic enzyme SNP affected working memory, but not attention, we predicted that both SNPs would modulate performance when the two systems interacted and working memory was manipulated by attention. We found the scale of visuospatial attention deployed around a target affected memory for location of that target. Memory performance was modulated by the two SNPs. CHRNA4 C/C homozygotes and DBH G allele carriers showed the best memory performance but also the greatest benefit of visuospatial attention on memory. Overall, however, the CHRNA4 SNP exerted a stronger effect than the DBH SNP on memory performance when visuospatial attention was manipulated. This evidence of an integrated cholinergic influence on working memory performance under attentional manipulation is consistent with the view that working memory and visuospatial attention are separate systems which can interact.

  10. Early Auditory Evoked Potential Is Modulated by Selective Attention and Related to Individual Differences in Visual Working Memory Capacity

    PubMed Central

    Giuliano, Ryan J.; Karns, Christina M.; Neville, Helen J.; Hillyard, Steven A.

    2015-01-01

    A growing body of research suggests that the predictive power of working memory (WM) capacity for measures of intellectual aptitude is due to the ability to control attention and select relevant information. Crucially, attentional mechanisms implicated in controlling access to WM are assumed to be domain-general, yet reports of enhanced attentional abilities in individuals with larger WM capacities are primarily within the visual domain. Here, we directly test the link between WM capacity and early attentional gating across sensory domains, hypothesizing that measures of visual WM capacity should predict an individual’s capacity to allocate auditory selective attention. To address this question, auditory ERPs were recorded in a linguistic dichotic listening task, and individual differences in ERP modulations by attention were correlated with estimates of WM capacity obtained in a separate visual change detection task. Auditory selective attention enhanced ERP amplitudes at an early latency (ca. 70–90 msec), with larger P1 components elicited by linguistic probes embedded in an attended narrative. Moreover, this effect was associated with greater individual estimates of visual WM capacity. These findings support the view that domain-general attentional control mechanisms underlie the wide variation of WM capacity across individuals. PMID:25000526

  11. Attention Modulation by Proportion Congruency: The Asymmetrical List Shifting Effect

    ERIC Educational Resources Information Center

    Abrahamse, Elger L.; Duthoo, Wout; Notebaert, Wim; Risko, Evan F.

    2013-01-01

    Proportion congruency effects represent hallmark phenomena in current theorizing about cognitive control. This is based on the notion that proportion congruency determines the relative levels of attention to relevant and irrelevant information in conflict tasks. However, little empirical evidence exists that uniquely supports such an attention…

  12. Central Inhibition Ability Modulates Attention-Induced Motion Blindness

    ERIC Educational Resources Information Center

    Milders, Maarten; Hay, Julia; Sahraie, Arash; Niedeggen, Michael

    2004-01-01

    Impaired motion perception can be induced in normal observers in a rapid serial visual presentation task. Essential for this effect is the presence of motion distractors prior to the motion target, and we proposed that this attention-induced motion blindness results from high-level inhibition produced by the distractors. To investigate this, we…

  13. Self-Attributed Body-Shadows Modulate Tactile Attention

    ERIC Educational Resources Information Center

    Pavani, Francesco; Galfano, Giovanni

    2007-01-01

    Our body-shadows are special stimuli in the visual world. They often have anatomical resemblance with our own body-parts and move as our body moves, with spatio-temporal correlation. Here, we show that self-attributed body-shadows cue attention to the body-part they refer to, rather than the location they occupy. Using speeded spatial…

  14. Rewards modulate saccade latency but not exogenous spatial attention

    PubMed Central

    Dunne, Stephen; Ellison, Amanda; Smith, Daniel T.

    2015-01-01

    The eye movement system is sensitive to reward. However, whilst the eye movement system is extremely flexible, the extent to which changes to oculomotor behavior induced by reward paradigms persist beyond the training period or transfer to other oculomotor tasks is unclear. To address these issues we examined the effects of presenting feedback that represented small monetary rewards to spatial locations on the latency of saccadic eye movements, the time-course of learning and extinction of the effects of rewarding saccades on exogenous spatial attention and oculomotor inhibition of return. Reward feedback produced a relative facilitation of saccadic latency in a stimulus driven saccade task which persisted for three blocks of extinction trials. However, this hemifield-specific effect failed to transfer to peripheral cueing tasks. We conclude that rewarding specific spatial locations is unlikely to induce long-term, systemic changes to the human oculomotor or attention systems. PMID:26284004

  15. Social exclusion modulates priorities of attention allocation in cognitive control.

    PubMed

    Xu, Mengsi; Li, Zhiai; Diao, Liuting; Zhang, Lijie; Yuan, Jiajin; Ding, Cody; Yang, Dong

    2016-01-01

    Many studies have investigated how exclusion affects cognitive control and have reported inconsistent results. However, these studies usually treated cognitive control as a unitary concept, whereas it actually involved two main sub-processes: conflict detection and response implementation. Furthermore, existing studies have focused primarily on exclusion's effects on conscious cognitive control, while recent studies have shown the existence of unconscious cognitive control. Therefore, the present study investigated whether and how exclusion affects the sub-processes underlying conscious and unconscious cognitive control differently. The Cyberball game was used to manipulate social exclusion and participants subsequently performed a masked Go/No-Go task during which event-related potentials were measured. For conscious cognitive control, excluded participants showed a larger N2 but smaller P3 effects than included participants, suggesting that excluded people invest more attention in conscious conflict detection, but less in conscious inhibition of impulsive responses. However, for unconscious cognitive control, excluded participants showed a smaller N2 but larger P3 effects than included participants, suggesting that excluded people invest less attention in unconscious conflict detection, but more in unconscious inhibition of impulsive responses. Together, these results suggest that exclusion causes people to rebalance attention allocation priorities for cognitive control according to a more flexible and adaptive strategy. PMID:27511746

  16. Social exclusion modulates priorities of attention allocation in cognitive control

    PubMed Central

    Xu, Mengsi; Li, Zhiai; Diao, Liuting; Zhang, Lijie; Yuan, Jiajin; Ding, Cody; Yang, Dong

    2016-01-01

    Many studies have investigated how exclusion affects cognitive control and have reported inconsistent results. However, these studies usually treated cognitive control as a unitary concept, whereas it actually involved two main sub-processes: conflict detection and response implementation. Furthermore, existing studies have focused primarily on exclusion’s effects on conscious cognitive control, while recent studies have shown the existence of unconscious cognitive control. Therefore, the present study investigated whether and how exclusion affects the sub-processes underlying conscious and unconscious cognitive control differently. The Cyberball game was used to manipulate social exclusion and participants subsequently performed a masked Go/No-Go task during which event-related potentials were measured. For conscious cognitive control, excluded participants showed a larger N2 but smaller P3 effects than included participants, suggesting that excluded people invest more attention in conscious conflict detection, but less in conscious inhibition of impulsive responses. However, for unconscious cognitive control, excluded participants showed a smaller N2 but larger P3 effects than included participants, suggesting that excluded people invest less attention in unconscious conflict detection, but more in unconscious inhibition of impulsive responses. Together, these results suggest that exclusion causes people to rebalance attention allocation priorities for cognitive control according to a more flexible and adaptive strategy. PMID:27511746

  17. An evaluation of the response modulation hypothesis in relation to attention-deficit/hyperactivity disorder.

    PubMed

    Farmer, Richard F; Rucklidge, Julia J

    2006-08-01

    Several hypotheses related to Newman's (e.g., Patterson & Newman, 1993) response modulation hypothesis were examined among adolescents with attention-deficit/hyperactivity disorder (ADHD; n=18) and normal controls (n=23). Consistent with predictions, youth with ADHD committed more passive avoidance errors (PAEs) than controls during the latter trials of a computerized go/no go task with mixed incentives, and this effect remained significant or marginally significant even after common variance associated with variables that covary with ADHD (i.e., IQ, oppositional-defiant/conduct disorder [ODD/CD] symptoms, anxious/depressed mood) was removed. While a moderate inverse association was observed between PAE frequency and the amount of time spent viewing response feedback following punishment, both categorical (diagnostic) and dimensional analyses of ADHD symptomatology indicated that ADHD and reflection on punishment feedback are uniquely associated with PAE commission. Findings from this study are discussed in relation to models of disinhibition applicable to youth with ADHD.

  18. Mindfulness starts with the body: somatosensory attention and top-down modulation of cortical alpha rhythms in mindfulness meditation.

    PubMed

    Kerr, Catherine E; Sacchet, Matthew D; Lazar, Sara W; Moore, Christopher I; Jones, Stephanie R

    2013-01-01

    Using a common set of mindfulness exercises, mindfulness based stress reduction (MBSR) and mindfulness based cognitive therapy (MBCT) have been shown to reduce distress in chronic pain and decrease risk of depression relapse. These standardized mindfulness (ST-Mindfulness) practices predominantly require attending to breath and body sensations. Here, we offer a novel view of ST-Mindfulness's somatic focus as a form of training for optimizing attentional modulation of 7-14 Hz alpha rhythms that play a key role in filtering inputs to primary sensory neocortex and organizing the flow of sensory information in the brain. In support of the framework, we describe our previous finding that ST-Mindfulness enhanced attentional regulation of alpha in primary somatosensory cortex (SI). The framework allows us to make several predictions. In chronic pain, we predict somatic attention in ST-Mindfulness "de-biases" alpha in SI, freeing up pain-focused attentional resources. In depression relapse, we predict ST-Mindfulness's somatic attention competes with internally focused rumination, as internally focused cognitive processes (including working memory) rely on alpha filtering of sensory input. Our computational model predicts ST-Mindfulness enhances top-down modulation of alpha by facilitating precise alterations in timing and efficacy of SI thalamocortical inputs. We conclude by considering how the framework aligns with Buddhist teachings that mindfulness starts with "mindfulness of the body." Translating this theory into neurophysiology, we hypothesize that with its somatic focus, mindfulness' top-down alpha rhythm modulation in SI enhances gain control which, in turn, sensitizes practitioners to better detect and regulate when the mind wanders from its somatic focus. This enhanced regulation of somatic mind-wandering may be an important early stage of mindfulness training that leads to enhanced cognitive regulation and metacognition.

  19. Modulation of Oscillatory Neuronal Synchronization by Selective Visual Attention

    NASA Astrophysics Data System (ADS)

    Fries, Pascal; Reynolds, John H.; Rorie, Alan E.; Desimone, Robert

    2001-02-01

    In crowded visual scenes, attention is needed to select relevant stimuli. To study the underlying mechanisms, we recorded neurons in cortical area V4 while macaque monkeys attended to behaviorally relevant stimuli and ignored distracters. Neurons activated by the attended stimulus showed increased gamma-frequency (35 to 90 hertz) synchronization but reduced low-frequency (<17 hertz) synchronization compared with neurons at nearby V4 sites activated by distracters. Because postsynaptic integration times are short, these localized changes in synchronization may serve to amplify behaviorally relevant signals in the cortex.

  20. The novelty exploration bonus and its attentional modulation.

    PubMed

    Krebs, Ruth M; Schott, Björn H; Schütze, Hartmut; Düzel, Emrah

    2009-09-01

    We hypothesized that novel stimuli represent salient learning signals that can motivate 'exploration' in search for potential rewards. In computational theories of reinforcement learning, this is referred to as the novelty 'exploration bonus' for rewards. If true, stimulus novelty should enhance the reward anticipation signals in brain areas that are part of dopaminergic circuitry and thereby reduce responses to reward outcomes. We investigated this hypothesis in two fMRI experiments. Images of complex natural scenes predicted monetary reward or a neutral outcome by virtue of depicting either indoor or outdoor scenes. Half of the reward-predicting and neutral images had been familiarized the day before, the other half were novel. In experiment 1, subjects indicated whether images were novel or familiar, whereas in experiment 2, they explicitly decided whether or not images predicted reward by depicting indoor or outdoor scenes. Novelty led to the hypothesized enhancement of mesolimbic reward prediction responses and concomitant reduction of mesolimbic responses to reward outcomes. However, this effect was strongly task-dependent and occurred only in experiment 2, when the reward-predicting property of each image was attended. Recognition memory for the novel and familiar stimuli (after 24h) was enhanced by reward anticipation in both tasks. These findings are compatible with the proposition that novelty can act as a bonus for rewards under conditions when rewards are explicitly attended, thus biasing the organism towards reward anticipation and providing a motivational signal for exploration.

  1. Nonverbal communicative signals modulate attention to object properties.

    PubMed

    Marno, Hanna; Davelaar, Eddy J; Csibra, Gergely

    2014-04-01

    We investigated whether the social context in which an object is experienced influences the encoding of its various properties. We hypothesized that when an object is observed in a communicative context, its intrinsic features (such as its shape) would be preferentially encoded at the expense of its extrinsic properties (such as its location). In 3 experiments, participants were presented with brief movies, in which an actor either performed a noncommunicative action toward 1 of 5 different meaningless objects, or communicatively pointed at 1 of them. A subsequent static image, in which either the location or the identity of an object changed, tested participants' attention to these 2 kinds of information. Throughout the 3 experiments we found that communicative cues tended to facilitate identity change detection and to impede location change detection, whereas in the noncommunicative contexts we did not find such a bidirectional effect of cueing. The results also revealed that the effect of the communicative context was a result the presence of ostensive-communicative signals before the object-directed action, and not to the pointing gesture per se. We propose that such an attentional bias forms an inherent part of human communication, and function to facilitate social learning by communication. PMID:24294871

  2. Modulation of Automatic Semantic Priming by Feature-Specific Attention Allocation

    ERIC Educational Resources Information Center

    Spruyt, Adriaan; De Houwer, Jan; Hermans, Dirk

    2009-01-01

    We argue that the semantic analysis of task-irrelevant stimuli is modulated by feature-specific attention allocation. In line with this hypothesis, we found semantic priming of pronunciation responses to depend upon the extent to which participants focused their attention upon specific semantic stimulus dimensions. In Experiment 1, we examined the…

  3. Prediction and perception: Defensive startle modulation.

    PubMed

    Sege, Christopher T; Bradley, Margaret M; Lang, Peter J

    2015-12-01

    Previous research indicates that predictive cues can dampen subsequent defensive reactions. The present study investigated whether effects of cuing are specific to aversive stimuli, using modulation of the blink startle reflex as a measure of emotional reactivity. Participants viewed pictures depicting violence, romance/erotica, or mundane content. On half of all trials, a cue (color) predicted the content of the upcoming picture; on the remaining trials, scenes were presented without a cue. Acoustic startle probes were presented during picture viewing on trials with predictive cues and trials without a cue. Replicating previous studies, blink reflexes elicited when viewing violent pictures that had not been preceded by a cue were potentiated compared to uncued mundane scenes, and reflexes were attenuated when viewing scenes of erotica/romance that had not been cued. On the other hand, reflex potentiation when viewing scenes of violence (relative to mundane scenes) was eliminated when these pictures were preceded by a predictive cue, whereas scenes of romance prompted reliable reflex attenuation regardless of whether pictures were cued or not. Taken together, the data suggest that cuing elicits an anticipatory coping process that is specific to aversive stimuli.

  4. Prediction and perception: Defensive startle modulation.

    PubMed

    Sege, Christopher T; Bradley, Margaret M; Lang, Peter J

    2015-12-01

    Previous research indicates that predictive cues can dampen subsequent defensive reactions. The present study investigated whether effects of cuing are specific to aversive stimuli, using modulation of the blink startle reflex as a measure of emotional reactivity. Participants viewed pictures depicting violence, romance/erotica, or mundane content. On half of all trials, a cue (color) predicted the content of the upcoming picture; on the remaining trials, scenes were presented without a cue. Acoustic startle probes were presented during picture viewing on trials with predictive cues and trials without a cue. Replicating previous studies, blink reflexes elicited when viewing violent pictures that had not been preceded by a cue were potentiated compared to uncued mundane scenes, and reflexes were attenuated when viewing scenes of erotica/romance that had not been cued. On the other hand, reflex potentiation when viewing scenes of violence (relative to mundane scenes) was eliminated when these pictures were preceded by a predictive cue, whereas scenes of romance prompted reliable reflex attenuation regardless of whether pictures were cued or not. Taken together, the data suggest that cuing elicits an anticipatory coping process that is specific to aversive stimuli. PMID:26399464

  5. Dopamine Transporter Genotype Predicts Attentional Asymmetry in Healthy Adults

    ERIC Educational Resources Information Center

    Newman, Daniel P.; O'Connell, Redmond G.; Nathan, Pradeep J.; Bellgrove, Mark A.

    2012-01-01

    A number of recent studies suggest that DNA variation in the dopamine transporter gene (DAT1) influences spatial attention asymmetry in clinical populations such as ADHD, but confirmation in non-clinical samples is required. Since non-spatial factors such as attentional load have been shown to influence spatial biases in clinical conditions, here…

  6. Attentional modulation of external speech attribution in patients with hallucinations and delusions.

    PubMed

    Ilankovic, Lana Marija; Allen, Paul P; Engel, Rolf; Kambeitz, Joseph; Riedel, Michael; Müller, Norbert; Hennig-Fast, Kristina

    2011-04-01

    A range of psychological theories have been proposed to account for the experience of auditory hallucinations and delusions in schizophrenic patients. Most influential theories are those implicating the defective self-monitoring of inner speech. Some recent studies measured response bias independently of self-monitoring and found the results inconsistent with the defective self-monitoring model, but explained by an externalizing response bias. We aimed to investigate the role of attentional bias in external misattribution of source by modulating participant's endogenous expectancies. Comparisons were made between patients with paranoid schizophrenia (N=23) and matched healthy controls (N=23) who participated in two different versions of an audio-visual task, which differed based upon level of the cue predictiveness. The acoustic characteristic of voice was altered in half of the trials by shifting the pitch (distortion). Participants passively listened to recordings of single adjectives spoken in their own and another person's voice (alien) preceded by their own or another person's (alien) face and made self/non self judgments about the source. The patients showed increased error rates comparing to controls, when listening to the distorted self spoken words, misidentifying their own speech as produced by others. Importantly, patients made significantly more errors across all the invalid cue conditions. This suggests not only the presence of pathological misattribution bias, but also an inadequate balance between top-down and bottom-up attentional processes in the patients, which could be responsible for misattribution of the ambiguous sensory material. PMID:21241719

  7. Attention modulates the dorsal striatum response to love stimuli.

    PubMed

    Langeslag, Sandra J E; van der Veen, Frederik M; Röder, Christian H

    2014-02-01

    In previous functional magnetic resonance imaging (fMRI) studies concerning romantic love, several brain regions including the caudate and putamen have consistently been found to be more responsive to beloved-related than control stimuli. In those studies, infatuated individuals were typically instructed to passively view the stimuli or to think of the viewed person. In the current study, we examined how the instruction to attend to, or ignore the beloved modulates the response of these brain areas. Infatuated individuals performed an oddball task in which pictures of their beloved and friend served as targets and distractors. The dorsal striatum showed greater activation for the beloved than friend, but only when they were targets. The dorsal striatum actually tended to show less activation for the beloved than the friend when they were distractors. The longer the love and relationship duration, the smaller the response of the dorsal striatum to beloved-distractor stimuli was. We interpret our findings in terms of reinforcement learning. By virtue of using a cognitive task with a full factorial design, we show that the dorsal striatum is not activated by beloved-related information per se, but only by beloved-related information that is attended.

  8. Spatial attention modulates center-surround interactions in macaque visual area V4

    PubMed Central

    Sundberg, Kristy A.; Mitchell, Jude F.; Reynolds, John H.

    2010-01-01

    Summary In natural viewing a visual stimulus that is the target of attention is generally surrounded by many irrelevant distracters. Stimuli falling in the receptive field surround can influence the neuronal response evoked by a stimulus appearing within the classical receptive field. Such modulation by task-irrelevant distracters may degrade the target-related neuronal signal. We therefore examined whether directing attention to a target stimulus can reduce the influence of task-irrelevant distracters on neuronal response. We find that in area V4 attention to a stimulus within a neuron’s receptive field filters out a large fraction of the suppression induced by distracters appearing in the surround. When attention is instead directed to the surround stimulus suppression is increased, thereby filtering out part of the neuronal response to the irrelevant distracter positioned within the receptive field. These findings demonstrate that attention modulates the neural mechanisms that give rise to center-surround interactions. PMID:19324003

  9. Meditation-induced states predict attentional control over time.

    PubMed

    Colzato, Lorenza S; Sellaro, Roberta; Samara, Iliana; Baas, Matthijs; Hommel, Bernhard

    2015-12-01

    Meditation is becoming an increasingly popular topic for scientific research and various effects of extensive meditation practice (ranging from weeks to several years) on cognitive processes have been demonstrated. Here we show that extensive practice may not be necessary to achieve those effects. Healthy adult non-meditators underwent a brief single session of either focused attention meditation (FAM), which is assumed to increase top-down control, or open monitoring meditation (OMM), which is assumed to weaken top-down control, before performing an Attentional Blink (AB) task - which assesses the efficiency of allocating attention over time. The size of the AB was considerably smaller after OMM than after FAM, which suggests that engaging in meditation immediately creates a cognitive-control state that has a specific impact on how people allocate their attention over time.

  10. Noise Prediction Module for Offset Stream Nozzles

    NASA Technical Reports Server (NTRS)

    Henderson, Brenda S.

    2011-01-01

    A Modern Design of Experiments (MDOE) analysis of data acquired for an offset stream technology was presented. The data acquisition and concept development were funded under a Supersonics NRA NNX07AC62A awarded to Dimitri Papamoschou at University of California, Irvine. The technology involved the introduction of airfoils in the fan stream of a bypass ratio (BPR) two nozzle system operated at transonic exhaust speeds. The vanes deflected the fan stream relative to the core stream and resulted in reduced sideline noise for polar angles in the peak jet noise direction. Noise prediction models were developed for a range of vane configurations. The models interface with an existing ANOPP module and can be used or future system level studies.

  11. Bridging prediction and attention in current research on perception and action.

    PubMed

    Schröger, Erich; Kotz, Sonja A; SanMiguel, Iria

    2015-11-11

    Prediction and attention are fundamental brain functions in the service of perception and action. Theories on prediction relate to neural (mental) models inferring about (present or future) sensory or action-related information, whereas theories of attention are about the control of information flow underlying perception and action. Both concepts are related and not always clearly distinguishable. The special issue includes current research on prediction and attention in various subfields of perception and action. It especially considers interactions between predictive and attentive processes, which constitute a newly emerging and highly interesting field of research. As outlined in this editorial, the contributions in this special issue allow specifying as well as bridging concepts on prediction and attention. The joint consideration of prediction and attention also reveals common functional principles of perception and action.

  12. Dissociation predicts later attention problems in sexually abused children

    PubMed Central

    Kaplow, Julie B.; Hall, Erin; Koenen, Karestan C.; Dodge, Kenneth A.; Amaya-Jackson, Lisa

    2008-01-01

    Objective The goals of this research are to develop and test a prospective model of attention problems in sexually abused children that includes fixed variables (e.g., gender), trauma, and disclosure-related pathways. Methods At Time 1, fixed variables, trauma variables, and stress reactions upon disclosure were assessed in 156 children aged 8 to 13 years. At the Time 2 follow-up (8 to 36 months following the initial interview), 56 of the children were assessed for attention problems. Results A path analysis involving a series of hierarchically-nested, ordinary least squares multiple regression analyses indicated two direct paths to attention problems including the child’s relationship to the perpetrator (β = .23) and dissociation measured immediately after disclosure (β = .53), while controlling for concurrent externalizing behavior (β = .43). Posttraumatic stress symptoms were only indirectly associated with attention problems via dissociation. Taken together, these pathways accounted for approximately 52% of the variance in attention problems and provided an excellent fit to the data. Conclusions Children who report dissociative symptoms upon disclosure of CSA and/or were sexually abused by someone within their family are at an increased risk of developing attention problems. Practice Implications: Findings from this study indicate that children who experienced sexual abuse at an earlier age, by someone within their family, and/or report symptoms of dissociation during disclosure are especially likely to benefit from intervention. Effective interventions should involve (1) providing emotion regulation and coping skills; and (2) helping children to process traumatic aspects of the abuse to reduce the cyclic nature of traumatic reminders leading to unmanageable stress and dissociation. PMID:18308391

  13. Attention-dependent modulation of neural activity in primary sensorimotor cortex

    PubMed Central

    Milnik, Annette; Nowak, Isabella; Müller, Notger G

    2013-01-01

    Although motor tasks at most times do not require much attention, there are findings that attention can alter neuronal activity not only in higher motor areas but also within the primary sensorimotor cortex. However, these findings are equivocal as attention effects were investigated only in either the dominant or the nondominant hand; attention was operationalized either as concentration (i.e., attention directed to motor task) or as distraction (i.e., attention directed away from motor task), the complexity of motor tasks varied and almost no left-handers were studied. Therefore, in this study, both right- and left-handers were investigated with an externally paced button press task in which subjects typed with the index finger of the dominant, nondominant, or both hands. We introduced four different attention levels: attention-modulation-free, distraction (counting backward), concentration on the moving finger, and divided concentration during bimanual movement. We found that distraction reduced neuronal activity in both contra- and ipsilateral primary sensorimotor cortex when the nondominant hand was tapping in both handedness groups. At the same time, distraction activated the dorsal frontoparietal attention network and deactivated the ventral default network. We conclude that difficulty and training status of both the motor and cognitive task, as well as usage of the dominant versus the nondominant hand, are crucial for the presence and magnitude of attention effects on sensorimotor cortex activity. In the case of a very simple button press task, attention modulation is seen for the nondominant hand under distraction and in both handedness groups. PMID:23532795

  14. Fearful, surprised, happy, and angry facial expressions modulate gaze-oriented attention: Behavioral and ERP evidence

    PubMed Central

    Lassalle, Amandine; Itier, Roxane J.

    2014-01-01

    The impact of emotions on gaze-oriented attention was investigated in non-anxious participants. A neutral face cue with straight gaze was presented, which then averted its gaze to the side while remaining neutral or expressing an emotion (fear/surprise in Exp.1 and anger/happiness in Exp.2). Localization of a subsequent target was faster at the gazed-at location (congruent condition) than at the non-gazed-at location (incongruent condition). This Gaze-Orienting Effect (GOE) was enhanced for fear, surprise, and anger, compared to neutral expressions which did not differ from happy expressions. In addition, Event Related Potentials (ERPs) to the target showed a congruency effect on P1 for fear and surprise and a left lateralized congruency effect on P1 for happy faces, suggesting that target visual processing was also influenced by attention to gaze and emotions. Finally, at cue presentation, early postero-lateral (Early Directing Attention Negativity (EDAN)) and later antero-lateral (Anterior Directing Attention Negativity (ADAN)) attention-related ERP components were observed, reflecting, respectively, the shift of attention and its holding at gazed-at locations. These two components were not modulated by emotions. Together, these findings show that the processing of social signals such as gaze and facial expression interact rather late and in a complex manner to modulate spatial attention. PMID:24047232

  15. Top-down and bottom-up attention cause the ventriloquism effect with distinct electroencephalography modulations

    PubMed Central

    Kumagai, Toshihiro

    2016-01-01

    The ventriloquism effect is a critical phenomenon for understanding the underlying mechanisms of multisensory integration. Cross-modal spatial attention causes a distortion of sound localization, although the neural basis of the effect remains an unanswered question. We hypothesized that top-down and bottom-up visual-spatial attention causes the ventriloquism effect with different modulations of ongoing neural oscillation. To test this hypothesis, human scalp electroencephalography (EEG) was measured during a sound localization task. Top-down attention suppressed the EEG amplitude in the alpha frequency (10 Hz) over the contralateral temporal electrode sites to visual cue hemifields. Bottom-up attention shifted the EEG phase to the theta frequency (7 Hz), rather than suppressing the amplitude. Two different neural mechanisms of ongoing neural oscillation contributed toward the ventriloquism effect, with different spatial attention. PMID:27128725

  16. Target-object integration, attention distribution, and object orientation interactively modulate object-based selection.

    PubMed

    Al-Janabi, Shahd; Greenberg, Adam S

    2016-10-01

    The representational basis of attentional selection can be object-based. Various studies have suggested, however, that object-based selection is less robust than spatial selection across experimental paradigms. We sought to examine the manner by which the following factors might explain this variation: Target-Object Integration (targets 'on' vs. part 'of' an object), Attention Distribution (narrow vs. wide), and Object Orientation (horizontal vs. vertical). In Experiment 1, participants discriminated between two targets presented 'on' an object in one session, or presented as a change 'of' an object in another session. There was no spatial cue-thus, attention was initially focused widely-and the objects were horizontal or vertical. We found evidence of object-based selection only when targets constituted a change 'of' an object. Additionally, object orientation modulated the sign of object-based selection: We observed a same-object advantage for horizontal objects, but a same-object cost for vertical objects. In Experiment 2, an informative cue preceded a single target presented 'on' an object or as a change 'of' an object (thus, attention was initially focused narrowly). Unlike in Experiment 1, we found evidence of object-based selection independent of target-object integration. We again found that the sign of selection was modulated by the objects' orientation. This result may reflect a meridian effect, which emerged due to anisotropies in the cortical representations when attention is oriented endogenously. Experiment 3 revealed that object orientation did not modulate object-based selection when attention was oriented exogenously. Our findings suggest that target-object integration, attention distribution, and object orientation modulate object-based selection, but only in combination.

  17. Target-object integration, attention distribution, and object orientation interactively modulate object-based selection.

    PubMed

    Al-Janabi, Shahd; Greenberg, Adam S

    2016-10-01

    The representational basis of attentional selection can be object-based. Various studies have suggested, however, that object-based selection is less robust than spatial selection across experimental paradigms. We sought to examine the manner by which the following factors might explain this variation: Target-Object Integration (targets 'on' vs. part 'of' an object), Attention Distribution (narrow vs. wide), and Object Orientation (horizontal vs. vertical). In Experiment 1, participants discriminated between two targets presented 'on' an object in one session, or presented as a change 'of' an object in another session. There was no spatial cue-thus, attention was initially focused widely-and the objects were horizontal or vertical. We found evidence of object-based selection only when targets constituted a change 'of' an object. Additionally, object orientation modulated the sign of object-based selection: We observed a same-object advantage for horizontal objects, but a same-object cost for vertical objects. In Experiment 2, an informative cue preceded a single target presented 'on' an object or as a change 'of' an object (thus, attention was initially focused narrowly). Unlike in Experiment 1, we found evidence of object-based selection independent of target-object integration. We again found that the sign of selection was modulated by the objects' orientation. This result may reflect a meridian effect, which emerged due to anisotropies in the cortical representations when attention is oriented endogenously. Experiment 3 revealed that object orientation did not modulate object-based selection when attention was oriented exogenously. Our findings suggest that target-object integration, attention distribution, and object orientation modulate object-based selection, but only in combination. PMID:27198915

  18. Learned Predictiveness Influences Rapid Attentional Capture: Evidence from the Dot Probe Task

    ERIC Educational Resources Information Center

    Le Pelley, Mike E.; Vadillo, Miguel; Luque, David

    2013-01-01

    Attentional theories of associative learning and categorization propose that learning about the predictiveness of a stimulus influences the amount of attention that is paid to that stimulus. Three experiments tested this idea by looking at the extent to which stimuli that had previously been experienced as predictive or nonpredictive in a…

  19. Selective and divided attention modulates auditory-vocal integration in the processing of pitch feedback errors.

    PubMed

    Liu, Ying; Hu, Huijing; Jones, Jeffery A; Guo, Zhiqiang; Li, Weifeng; Chen, Xi; Liu, Peng; Liu, Hanjun

    2015-08-01

    Speakers rapidly adjust their ongoing vocal productions to compensate for errors they hear in their auditory feedback. It is currently unclear what role attention plays in these vocal compensations. This event-related potential (ERP) study examined the influence of selective and divided attention on the vocal and cortical responses to pitch errors heard in auditory feedback regarding ongoing vocalisations. During the production of a sustained vowel, participants briefly heard their vocal pitch shifted up two semitones while they actively attended to auditory or visual events (selective attention), or both auditory and visual events (divided attention), or were not told to attend to either modality (control condition). The behavioral results showed that attending to the pitch perturbations elicited larger vocal compensations than attending to the visual stimuli. Moreover, ERPs were likewise sensitive to the attentional manipulations: P2 responses to pitch perturbations were larger when participants attended to the auditory stimuli compared to when they attended to the visual stimuli, and compared to when they were not explicitly told to attend to either the visual or auditory stimuli. By contrast, dividing attention between the auditory and visual modalities caused suppressed P2 responses relative to all the other conditions and caused enhanced N1 responses relative to the control condition. These findings provide strong evidence for the influence of attention on the mechanisms underlying the auditory-vocal integration in the processing of pitch feedback errors. In addition, selective attention and divided attention appear to modulate the neurobehavioral processing of pitch feedback errors in different ways.

  20. Dynamic attentional modulation of vision across space and time after right hemisphere stroke and in ageing

    PubMed Central

    Russell, Charlotte; Malhotra, Paresh; Deidda, Cristiana; Husain, Masud

    2013-01-01

    Introduction Attention modulates the availability of sensory information to conscious perception. In particular, there is evidence of pathological, spatial constriction of the effective field of vision in patients with right hemisphere damage when a central task exhausts available attentional capacity. In the current study we first examined whether this constriction might be modulated across both space and time in right hemisphere stroke patients without neglect. Then we tested healthy elderly people to determine whether non-pathological ageing also leads to spatiotemporal impairments of vision under conditions of high attention load. Methods Right hemisphere stroke patients completed a task at fixation while attempting to discriminate letters appearing in the periphery. Attentional load of the central task was modulated by increasing task difficulty. Peripheral letters appeared simultaneously with the central task or at different times (stimulus onset asynchronies, SOAs) after it. In a second study healthy elderly volunteers were tested with a modified version of this paradigm. Results Under conditions of high attention load right hemisphere stroke patients have a reduced effective visual field, over a significantly extended ‘attentional blink’, worse for items presented to their left. In the second study, older participants were unable to discriminate otherwise salient items across the visual field (left or right) when their attention capacity was loaded on the central task. This deficit extended temporally, with peripheral discrimination ability not returning to normal for up to 450 msec. Conclusions Dynamically tying up attention resources on a task at fixation can have profound effects in patient populations and in normal ageing. These results demonstrate that items can escape conscious detection across space and time, and can thereby impact significantly on visual perception in these groups. PMID:23245427

  1. Attention Deficit Hyperactivity Disorder and Sensory Modulation Disorder: A Comparison of Behavior and Physiology

    ERIC Educational Resources Information Center

    Miller, Lucy Jane; Nielsen, Darci M.; Schoen, Sarah A.

    2012-01-01

    Children with attention deficit hyperactivity disorder (ADHD) are impulsive, inattentive and hyperactive, while children with sensory modulation disorder (SMD), one subtype of Sensory Processing Disorder, have difficulty responding adaptively to daily sensory experiences. ADHD and SMD are often difficult to distinguish. To differentiate these…

  2. Self-construal priming selectively modulates the scope of visual attention.

    PubMed

    Liu, Zhuozhuo; Cheng, Menxue; Peng, Kaiping; Zhang, Dan

    2015-01-01

    Self-concept is one of the major factors to explain the cultural differences between East Asians and Westerners. In the field of visual attention, most studies have focused on the modulation of visual spatial-based attention, whereas possible influences of culture or self-concept on other types of visual attention remain largely unexplored. The present study investigated the possible modulation of visual feature-based attention by self-concept, using a within-group self-construal priming design. The experiment paradigm employed visual stimuli consisted of two intermixing random dot clouds presented in the focal visual field with red and green colors. After primed with an interdependent, independent, or neutral self-construal, the participants were instructed to attend to one of the focally presented dot cloud and respond to occasional luminance decrement events of the attended dot cloud. The detection of the focal events was found to be significantly faster when exogenously cued by a peripheral dot cloud of either the same or different colors as the attended focal dot cloud (congruent/incongruent), compared to the uncued condition. More importantly, the self-construal priming took effect only on the reaction time (RT) differences between the congruent and incongruent cued conditions: the participants responded much slower to incongruent cued events than congruent cued events under interdependent self-construal priming, while the RT difference was significantly smaller under independent self-construal priming. A closer look on the results suggests that the attention scope is selectively modulated by self-construal priming, and the modulation is mainly reflected by varying the degree of suppression on the processing of the incongruent contextual stimuli that do not share visual features with the focal object. Our findings provide new evidences that could possibly extend the current understanding on the cultural influence on visual attention.

  3. Spatial attention does not modulate holistic face processing, even when multiple faces are present.

    PubMed

    Norman, Liam J; Tokarev, Alexander

    2014-01-01

    The perception of faces is often considered to be unique in comparison with that of other objects in the world. The fact that faces are processed not by their constituent components but by the spatial configuration between those components (holistic face processing--HFP) is often used to support this. Despite two decades of research, however, there is no consensus as to whether or not HFP is a process that is subject to attentional modulation. Here, in two experiments, we used a method to direct spatial attention not previously used in studies of HFP--an exogenous spatial cue--as it offers a robust, rapid, and involuntary method of directing attention. In one experiment we demonstrate that the degree of HFP afforded to a face is not reduced when attention is directed away from that face. In a second experiment we replicate this finding even when the face is simultaneously flanked by other faces--a condition under which a face-specific processing module would, hypothetically, be more sensitive to attentional guidance. These results add to the argument that HFP is carried out independently of attention.

  4. Dissociable Modulation of Overt Visual Attention in Valence and Arousal Revealed by Topology of Scan Path

    PubMed Central

    Ni, Jianguang; Jiang, Huihui; Jin, Yixiang; Chen, Nanhui; Wang, Jianhong; Wang, Zhengbo; Luo, Yuejia; Ma, Yuanye; Hu, Xintian

    2011-01-01

    Emotional stimuli have evolutionary significance for the survival of organisms; therefore, they are attention-grabbing and are processed preferentially. The neural underpinnings of two principle emotional dimensions in affective space, valence (degree of pleasantness) and arousal (intensity of evoked emotion), have been shown to be dissociable in the olfactory, gustatory and memory systems. However, the separable roles of valence and arousal in scene perception are poorly understood. In this study, we asked how these two emotional dimensions modulate overt visual attention. Twenty-two healthy volunteers freely viewed images from the International Affective Picture System (IAPS) that were graded for affective levels of valence and arousal (high, medium, and low). Subjects' heads were immobilized and eye movements were recorded by camera to track overt shifts of visual attention. Algebraic graph-based approaches were introduced to model scan paths as weighted undirected path graphs, generating global topology metrics that characterize the algebraic connectivity of scan paths. Our data suggest that human subjects show different scanning patterns to stimuli with different affective ratings. Valence salient stimuli (with neutral arousal) elicited faster and larger shifts of attention, while arousal salient stimuli (with neutral valence) elicited local scanning, dense attention allocation and deep processing. Furthermore, our model revealed that the modulatory effect of valence was linearly related to the valence level, whereas the relation between the modulatory effect and the level of arousal was nonlinear. Hence, visual attention seems to be modulated by mechanisms that are separate for valence and arousal. PMID:21494331

  5. Temporal Expectation and Attention Jointly Modulate Auditory Oscillatory Activity in the Beta Band

    PubMed Central

    Todorovic, Ana; Schoffelen, Jan-Mathijs; van Ede, Freek; Maris, Eric; de Lange, Floris P.

    2015-01-01

    The neural response to a stimulus is influenced by endogenous factors such as expectation and attention. Current research suggests that expectation and attention exert their effects in opposite directions, where expectation decreases neural activity in sensory areas, while attention increases it. However, expectation and attention are usually studied either in isolation or confounded with each other. A recent study suggests that expectation and attention may act jointly on sensory processing, by increasing the neural response to expected events when they are attended, but decreasing it when they are unattended. Here we test this hypothesis in an auditory temporal cueing paradigm using magnetoencephalography in humans. In our study participants attended to, or away from, tones that could arrive at expected or unexpected moments. We found a decrease in auditory beta band synchrony to expected (versus unexpected) tones if they were unattended, but no difference if they were attended. Modulations in beta power were already evident prior to the expected onset times of the tones. These findings suggest that expectation and attention jointly modulate sensory processing. PMID:25799572

  6. Auditory selective attention to speech modulates activity in the visual word form area.

    PubMed

    Yoncheva, Yuliya N; Zevin, Jason D; Maurer, Urs; McCandliss, Bruce D

    2010-03-01

    Selective attention to speech versus nonspeech signals in complex auditory input could produce top-down modulation of cortical regions previously linked to perception of spoken, and even visual, words. To isolate such top-down attentional effects, we contrasted 2 equally challenging active listening tasks, performed on the same complex auditory stimuli (words overlaid with a series of 3 tones). Instructions required selectively attending to either the speech signals (in service of rhyme judgment) or the melodic signals (tone-triplet matching). Selective attention to speech, relative to attention to melody, was associated with blood oxygenation level-dependent (BOLD) increases during functional magnetic resonance imaging (fMRI) in left inferior frontal gyrus, temporal regions, and the visual word form area (VWFA). Further investigation of the activity in visual regions revealed overall deactivation relative to baseline rest for both attention conditions. Topographic analysis demonstrated that while attending to melody drove deactivation equivalently across all fusiform regions of interest examined, attending to speech produced a regionally specific modulation: deactivation of all fusiform regions, except the VWFA. Results indicate that selective attention to speech can topographically tune extrastriate cortex, leading to increased activity in VWFA relative to surrounding regions, in line with the well-established connectivity between areas related to spoken and visual word perception in skilled readers.

  7. Object-based attention overrides perceptual load to modulate visual distraction

    PubMed Central

    Cosman, Joshua D.; Vecera, Shaun P.

    2014-01-01

    The ability to ignore task-irrelevant information and overcome distraction is central to our ability to efficiently carry out a number of tasks. One factor shown to strongly influence distraction is the perceptual load of the task being performed; as the perceptual load of task-relevant information processing increases, the likelihood that task-irrelevant information will be processed and interfere with task performance decreases. However, it has also been demonstrated that other attentional factors play an important role in whether or not distracting information affects performance. Specifically, object-based attention can modulate the extent of distractor processing, leaving open the possibility that object-based attention mechanisms may directly modulate the way in which perceptual load affects distractor processing. Here, we show that object-based attention dominates perceptual load to determine the extent of task-irrelevant information processing, with distractors affecting performance only when they are contained within the same object as the task-relevant search display. These results suggest that object-based attention effects play a central role in selective attention regardless of the perceptual load of the task being performed. PMID:22390296

  8. Modulation of alpha and gamma oscillations related to retrospectively orienting attention within working memory.

    PubMed

    Poch, Claudia; Campo, Pablo; Barnes, Gareth R

    2014-07-01

    Selective attention mechanisms allow us to focus on information that is relevant to the current behavior and, equally important, ignore irrelevant information. An influential model proposes that oscillatory neural activity in the alpha band serves as an active functional inhibitory mechanism. Recent studies have shown that, in the same way that attention can be selectively oriented to bias sensory processing in favor of relevant stimuli in perceptual tasks, it is also possible to retrospectively orient attention to internal representations held in working memory. However, these studies have not explored the associated oscillatory phenomena. In the current study, we analysed the patterns of neural oscillatory activity recorded with magnetoencephalography while participants performed a change detection task, in which a spatial retro-cue was presented during the maintenance period, indicating which item or items were relevant for subsequent retrieval. Participants benefited from retro-cues in terms of accuracy and reaction time. Retro-cues also modulated oscillatory activity in the alpha and gamma frequency bands. We observed greater alpha activity in a ventral visual region ipsilateral to the attended hemifield, thus supporting its suppressive role, i.e., a functional disengagement of task-irrelevant regions. Accompanying this modulation, we found an increase in gamma activity contralateral to the attended hemifield, which could reflect attentional orienting and selective processing. These findings suggest that the oscillatory mechanisms underlying attentional orienting to representations held in working memory are similar to those engaged when attention is oriented in the perceptual space. PMID:24750388

  9. Coherent oscillatory activity in monkey area v4 predicts successful allocation of attention.

    PubMed

    Taylor, K; Mandon, S; Freiwald, W A; Kreiter, A K

    2005-09-01

    Attention serves to select objects from often complex scenes for enhanced processing and perception. In particular, the perception of shape depends critically on attention for integrating the various parts of the selected object into a coherent representation of object shape. To study whether oscillatory neuronal synchrony may serve as a mechanism of attention in shape perception, we introduced a novel shape-tracking task requiring sustained attention to a morphing shape. Attention was found to strongly increase oscillatory currents underlying the recorded field potentials in the gamma-frequency range, thus indicating enhanced neuronal synchrony within the population of V4 neurons representing the attended stimulus. Errors indicating a misdirection of attention to the distracter instead of the target were preceded by a corresponding shift of oscillatory activity from the target's neuronal representation to that of the distracter. No such effect was observed for errors unrelated to attention. Modulations of the attention-dependent enhancement of oscillatory activity occurred in correspondence with changing attentional demands during the course of a trial. The specificity of the effect of attentional errors together with the close coupling between attentional demand and oscillatory activity support the hypothesis that oscillatory neuronal synchrony serves as a mechanism of attention.

  10. How arousal modulates memory: disentangling the effects of attention and retention.

    PubMed

    Sharot, Tali; Phelps, Elizabeth A

    2004-09-01

    Emotion may influence memory both by altering attention and perception during encoding and by affecting memory retention. To date, studies have focused on the enhancement of memory consolidation by arousal. However, they have failed to rule out a role for attention. To specifically link memory enhancement of arousing material to modulation of memory retention, we examined recognition of neutral and arousing words at two time points and under conditions that manipulate attention during encoding. Participants were briefly presented with an arousing or neutral word at the periphery, while fixating on a central word. Recognition of peripheral words was assessed either immediately or after 24 h. Whereas recognition of neutral words became worse over time, recognition of arousing words remained the same and was better than neutral word recognition at delay. The results indicate that arousal supports slower forgetting even when the difference in attentional resources allocated to stimuli is minimized.

  11. Reward expectation differentially modulates attentional behavior and activity in visual area V4.

    PubMed

    Baruni, Jalal K; Lau, Brian; Salzman, C Daniel

    2015-11-01

    Neural activity in visual area V4 is enhanced when attention is directed into neuronal receptive fields. However, the source of this enhancement is unclear, as most physiological studies have manipulated attention by changing the absolute reward associated with a particular location as well as its value relative to other locations. We trained monkeys to discriminate the orientation of two stimuli presented simultaneously in different hemifields while we independently varied the reward magnitude associated with correct discrimination at each location. Behavioral measures of attention were controlled by the relative value of each location. By contrast, neurons in V4 were consistently modulated by absolute reward value, exhibiting increased activity, increased gamma-band power and decreased trial-to-trial variability whenever receptive field locations were associated with large rewards. These data challenge the notion that the perceptual benefits of spatial attention rely on increased signal-to-noise in V4. Instead, these benefits likely derive from downstream selection mechanisms. PMID:26479590

  12. Attention deficit hyperactivity disorder and sensory modulation disorder: a comparison of behavior and physiology.

    PubMed

    Miller, Lucy Jane; Nielsen, Darci M; Schoen, Sarah A

    2012-01-01

    Children with attention deficit hyperactivity disorder (ADHD) are impulsive, inattentive and hyperactive, while children with sensory modulation disorder (SMD), one subtype of Sensory Processing Disorder, have difficulty responding adaptively to daily sensory experiences. ADHD and SMD are often difficult to distinguish. To differentiate these disorders in children, clinical ADHD, SMD, and dual diagnoses were assessed. All groups had significantly more sensory, attention, activity, impulsivity, and emotional difficulties than typical children, but with distinct profiles. Inattention was greater in ADHD compared to SMD. Dual diagnoses had more sensory-related behaviors than ADHD and more attentional difficulties than SMD. SMD had more sensory issues, somatic complaints, anxiety/depression, and difficulty adapting than ADHD. SMD had greater physiological/electrodermal reactivity to sensory stimuli than ADHD and typical controls. Parent-report measures identifying sensory, attentional, hyperactive, and impulsive difficulties varied in agreement with clinician's diagnoses. Evidence suggests ADHD and SMD are distinct diagnoses.

  13. The availability of attentional resources modulates the inhibitory strength related to weakly activated priming.

    PubMed

    Wang, Yongchun; Wang, Yonghui; Liu, Peng; Dai, Dongyang; Di, Meilin; Chen, Qiang

    2016-08-01

    The current study investigated the role of attention in inhibitory processes (the inhibitory processes described in the current study refer only to those associated with masked or flanked priming) using a mixed paradigm involving the negative compatibility effect (NCE) and object-based attention. Accumulating evidence suggests that attention can be spread more easily within the same object, which increases the availability of attentional resources, than across different objects. Accordingly, we manipulated distractor location (with primes presented in the same object versus presented in different objects) together with prime/target compatibility (compatible versus incompatible) and prime-distractor stimulus onset asynchrony (SOA, 23 ms vs 70 ms). The aim was to investigate whether inhibitory processes related to weakly activated priming, which have been previously assumed to be automatic, depend on the availability of attentional resources. The results of Experiment 1 showed a significant NCE for the 70-ms SOA when the prime and distractor were presented in the same object (greater attentional resource availability); however, reversed NCEs were obtained for all other conditions. Experiment 2 was designed to disentangle whether the results of Experiment 1 were affected by the prime position, and the results indicated that the prime position did not modulate the NCE in Experiment 1. Together, these results are consistent with the claim that the availability of attentional resources modulates the inhibitory strength related to weakly activated priming. Specifically, if attentional resources are assigned to the distractor when it is presented in the same object as the prime, the strength of the inhibition elicited by the distractor may increase and reverse the activation elicited by the prime, which could lead to a significant NCE. PMID:27198916

  14. Location of brain rhythms and their modulation by preparatory attention estimated by current density.

    PubMed

    Gómez, C M; Marco-Pallarés, J; Grau, C

    2006-08-30

    To test the hypothesis that there is a functional modulation of conventional EEG bands associated with preparatory attention, putative changes in the spontaneous brain rhythms and their associated cerebral sources were addressed. The goals of the present report were, first, to find the brain areas with maximal rhythmic activity before warning and imperative stimuli in a classic contingent negative variation (CNV) paradigm, and, second, to study the modulation of the EEG rhythms of these areas during the preparatory attention interval which precedes the S2 (imperative) stimulus. Trial by trial LORETA analysis found similar brain rhythm generators during both pre-S1 and pre-S2 intervals. Each theta, alpha and beta traditional EEG rhythm originates in several anatomically distinct brain structures. Preparatory attention is associated with a decrease in power in alpha (right and left occipital and temporal areas) and low-beta (left frontal, bilateral occipital and middle frontal areas) EEG bands. In these structures power changes associated with preparatory attention modulated either a dominant or a non-dominant oscillatory band, suggesting that non-dominant rhythms of a cerebral area have some functional relevance. Our results imply distributed regional sources for brain rhythms and support the view that during preparatory attention there is a modulation of the brain sources generating alpha and beta brain rhythms. Moreover, the proposed combined approach makes it possible to explore the definition of a given brain area not only anatomically, but also by the frequency content and the functional reactivity of the electrical rhythms that it generates. PMID:16875680

  15. Predict Attention Deficit Hyperactivity Disorder? Evidence -Based Medicine

    PubMed Central

    Bener, Abdulbari; Kamal, Madeeha

    2014-01-01

    Background: Attention deficit hyperactivity disorder (ADHD) is the most common behavioral disorders in children and recent studies reported a relationship between low levels of Vitamin D and incidence of ADHD. Aim: The aim of this study was to investigate the association between vitamin D deficiency and attention deficit hyperactivity disorder (ADHD). Also, to study the impact and role of vitamin D on the development of ADH in children. Design: This is a case-control study which was conducted in children below 18 years of age from June 2011 to May 2013 at the School Health and Primary Health care Clinics, Qatar. Methods and subjects: The study was based on 1,331 cases and 1,331 controls. The data collection instrument included socio-demographic & clinical data, physician diagnosis family history, BMI, and serum 25(OH) vitamin D, calcium, albumin, billirubin, magnesium, calcium, cholesterol, urea, triglyceride and phosphorus. Descriptive and univariate statistical analysis were performed. Results: Of the total number of 3470 children surveyed, 1331 of ADHD and 1,331 of healthy children gave their consent to participate in this study. The mean age (± SD, in years) for ADHD versus control children was 10.63±3.4 vs. 10.77±3.4. Overweight (7.7% vs 9.4%) and obesity (4.6% vs 7.7%) were significantly lower in ADHD children compared to their counterparts (P=0.001). Vitamin D deficiency was considerably higher in ADHD children compared to healthy children. The mean value of vitamin D in ADHD children was much lower than the normal value and there was a significant difference found in the mean values of vitamin D between ADHD (16.6±7.8 with median 16) and control children (23.5±9.9) (p<0.0001) and with median 23 (p = 0.006). Mean values of Calcium and phosphorous were significantly higher in control compared to ADHD children (p<0.001). 1331 of all ADHD children had 19.1% had severe vitamin D deficiency (< 10 ng/ml), 44.9% has moderate insufficient levels (between 10

  16. Selective attention to phonology dynamically modulates initial encoding of auditory words within the left hemisphere.

    PubMed

    Yoncheva, Yuliya; Maurer, Urs; Zevin, Jason D; McCandliss, Bruce D

    2014-08-15

    Selective attention to phonology, i.e., the ability to attend to sub-syllabic units within spoken words, is a critical precursor to literacy acquisition. Recent functional magnetic resonance imaging evidence has demonstrated that a left-lateralized network of frontal, temporal, and posterior language regions, including the visual word form area, supports this skill. The current event-related potential (ERP) study investigated the temporal dynamics of selective attention to phonology during spoken word perception. We tested the hypothesis that selective attention to phonology dynamically modulates stimulus encoding by recruiting left-lateralized processes specifically while the information critical for performance is unfolding. Selective attention to phonology was captured by manipulating listening goals: skilled adult readers attended to either rhyme or melody within auditory stimulus pairs. Each pair superimposed rhyming and melodic information ensuring identical sensory stimulation. Selective attention to phonology produced distinct early and late topographic ERP effects during stimulus encoding. Data-driven source localization analyses revealed that selective attention to phonology led to significantly greater recruitment of left-lateralized posterior and extensive temporal regions, which was notably concurrent with the rhyme-relevant information within the word. Furthermore, selective attention effects were specific to auditory stimulus encoding and not observed in response to cues, arguing against the notion that they reflect sustained task setting. Collectively, these results demonstrate that selective attention to phonology dynamically engages a left-lateralized network during the critical time-period of perception for achieving phonological analysis goals. These findings suggest a key role for selective attention in on-line phonological computations. Furthermore, these findings motivate future research on the role that neural mechanisms of attention may

  17. Selective attention to phonology dynamically modulates initial encoding of auditory words within the left hemisphere.

    PubMed

    Yoncheva, Yuliya; Maurer, Urs; Zevin, Jason D; McCandliss, Bruce D

    2014-08-15

    Selective attention to phonology, i.e., the ability to attend to sub-syllabic units within spoken words, is a critical precursor to literacy acquisition. Recent functional magnetic resonance imaging evidence has demonstrated that a left-lateralized network of frontal, temporal, and posterior language regions, including the visual word form area, supports this skill. The current event-related potential (ERP) study investigated the temporal dynamics of selective attention to phonology during spoken word perception. We tested the hypothesis that selective attention to phonology dynamically modulates stimulus encoding by recruiting left-lateralized processes specifically while the information critical for performance is unfolding. Selective attention to phonology was captured by manipulating listening goals: skilled adult readers attended to either rhyme or melody within auditory stimulus pairs. Each pair superimposed rhyming and melodic information ensuring identical sensory stimulation. Selective attention to phonology produced distinct early and late topographic ERP effects during stimulus encoding. Data-driven source localization analyses revealed that selective attention to phonology led to significantly greater recruitment of left-lateralized posterior and extensive temporal regions, which was notably concurrent with the rhyme-relevant information within the word. Furthermore, selective attention effects were specific to auditory stimulus encoding and not observed in response to cues, arguing against the notion that they reflect sustained task setting. Collectively, these results demonstrate that selective attention to phonology dynamically engages a left-lateralized network during the critical time-period of perception for achieving phonological analysis goals. These findings suggest a key role for selective attention in on-line phonological computations. Furthermore, these findings motivate future research on the role that neural mechanisms of attention may

  18. Quantifying attentional modulation of auditory-evoked cortical responses from single-trial electroencephalography

    PubMed Central

    Choi, Inyong; Rajaram, Siddharth; Varghese, Lenny A.; Shinn-Cunningham, Barbara G.

    2013-01-01

    Selective auditory attention is essential for human listeners to be able to communicate in multi-source environments. Selective attention is known to modulate the neural representation of the auditory scene, boosting the representation of a target sound relative to the background, but the strength of this modulation, and the mechanisms contributing to it, are not well understood. Here, listeners performed a behavioral experiment demanding sustained, focused spatial auditory attention while we measured cortical responses using electroencephalography (EEG). We presented three concurrent melodic streams; listeners were asked to attend and analyze the melodic contour of one of the streams, randomly selected from trial to trial. In a control task, listeners heard the same sound mixtures, but performed the contour judgment task on a series of visual arrows, ignoring all auditory streams. We found that the cortical responses could be fit as weighted sum of event-related potentials evoked by the stimulus onsets in the competing streams. The weighting to a given stream was roughly 10 dB higher when it was attended compared to when another auditory stream was attended; during the visual task, the auditory gains were intermediate. We then used a template-matching classification scheme to classify single-trial EEG results. We found that in all subjects, we could determine which stream the subject was attending significantly better than by chance. By directly quantifying the effect of selective attention on auditory cortical responses, these results reveal that focused auditory attention both suppresses the response to an unattended stream and enhances the response to an attended stream. The single-trial classification results add to the growing body of literature suggesting that auditory attentional modulation is sufficiently robust that it could be used as a control mechanism in brain–computer interfaces (BCIs). PMID:23576968

  19. Top-down modulation: the crossroads of perception, attention and memory

    NASA Astrophysics Data System (ADS)

    Gazzaley, Adam

    2010-02-01

    Research in our laboratory focuses on understanding the neural mechanisms that serve at the crossroads of perception, memory and attention, specifically exploring how brain region interactions underlie these abilities. To accomplish this, we study top-down modulation, the process by which we enhance neural activity associated with relevant information and suppress activity for irrelevant information, thus establishing a neural basis for all higher-order cognitive operations. We also study alterations in top-down modulation that occur with normal aging. Our experiments are performed on human participants, using a multimodal approach that integrates functional MRI (fMRI), transcranial magnetic stimulation (TMS) and electroencephalography (EEG).

  20. Multisensory perception of the six basic emotions is modulated by attentional instruction and unattended modality.

    PubMed

    Takagi, Sachiko; Hiramatsu, Saori; Tabei, Ken-Ichi; Tanaka, Akihiro

    2015-01-01

    Previous studies have shown that the perception of facial and vocal affective expressions interacts with each other. Facial expressions usually dominate vocal expressions when we perceive the emotions of face-voice stimuli. In most of these studies, participants were instructed to pay attention to the face or voice. Few studies compared the perceived emotions with and without specific instructions regarding the modality to which attention should be directed. Also, these studies used combinations of the face and voice which expresses two opposing emotions, which limits the generalizability of the findings. The purpose of this study is to examine whether the emotion perception is modulated by instructions to pay attention to the face or voice using the six basic emotions. Also we examine the modality dominance between the face and voice for each emotion category. Before the experiment, we recorded faces and voices which expresses the six basic emotions and orthogonally combined these faces and voices. Consequently, the emotional valence of visual and auditory information was either congruent or incongruent. In the experiment, there were unisensory and multisensory sessions. The multisensory session was divided into three blocks according to whether an instruction was given to pay attention to a given modality (face attention, voice attention, and no instruction). Participants judged whether the speaker expressed happiness, sadness, anger, fear, disgust, or surprise. Our results revealed that instructions to pay attention to one modality and congruency of the emotions between modalities modulated the modality dominance, and the modality dominance is differed for each emotion category. In particular, the modality dominance for anger changed according to each instruction. Analyses also revealed that the modality dominance suggested by the congruency effect can be explained in terms of the facilitation effect and the interference effect.

  1. Predictive Validity of Attentional Functions in Differentiating Children with and without ADHD: A Componential Analysis

    ERIC Educational Resources Information Center

    Kaufmann, Liane; Zieren, Nikola; Zotter, Sibylle; Karall, Daniela; Scholl-Burgi, Sabine; Haberlandt, Edda; Fimm, Bruno

    2010-01-01

    Aim: The objective of this study was to investigate which attentional components are of predictive utility in differentiating children with attention-deficit-hyperactivity disorder, combined type (ADHD-C) from their peers without ADHD. Methods: Thirty-four children participated in the study: 17 males with ADHD-C (mean age 10y 4mo, SD 1y 9mo) and…

  2. Predicting the Early Developmental Course of Symptoms of Attention Deficit Hyperactivity Disorder

    ERIC Educational Resources Information Center

    von Stauffenberg, Camilla; Campbell, Susan B.

    2007-01-01

    Data from the National Institute of Child Health and Human Development Study of Early Child Care were examined to test whether: attention deficit/hyperactivity disorder (ADHD) symptoms remain stable from 54 months through early elementary school; behavioral inhibition and attention deficits assessed at 54 months predict ADHD symptoms in elementary…

  3. Temporally dissociable mechanisms of self-control: early attentional filtering versus late value modulation.

    PubMed

    Harris, Alison; Hare, Todd; Rangel, Antonio

    2013-11-27

    Optimal decision-making often requires exercising self-control. A growing fMRI literature has implicated the dorsolateral prefrontal cortex (dlPFC) in successful self-control, but due to the limitations inherent in BOLD measures of brain activity, the neurocomputational role of this region has not been resolved. Here we exploit the high temporal resolution and whole-brain coverage of event-related potentials (ERPs) to test the hypothesis that dlPFC affects dietary self-control through two different mechanisms: attentional filtering and value modulation. Whereas attentional filtering of sensory input should occur early in the decision process, value modulation should occur later on, after the computation of stimulus values begins. Hungry human subjects were asked to make food choices while we measured neural activity using ERP in a natural condition, in which they responded freely and did not exhibit a tendency to regulate their diet, and in a self-control condition, in which they were given a financial incentive to lose weight. We then measured various neural markers associated with the attentional filtering and value modulation mechanisms across the decision period to test for changes in neural activity during the exercise of self-control. Consistent with the hypothesis, we found evidence for top-down attentional filtering early on in the decision period (150-200 ms poststimulus onset) as well as evidence for value modulation later in the process (450-650 ms poststimulus onset). We also found evidence that dlPFC plays a role in the deployment of both mechanisms. PMID:24285897

  4. Temporally Dissociable Mechanisms of Self-Control: Early Attentional Filtering Versus Late Value Modulation

    PubMed Central

    Hare, Todd; Rangel, Antonio

    2013-01-01

    Optimal decision-making often requires exercising self-control. A growing fMRI literature has implicated the dorsolateral prefrontal cortex (dlPFC) in successful self-control, but due to the limitations inherent in BOLD measures of brain activity, the neurocomputational role of this region has not been resolved. Here we exploit the high temporal resolution and whole-brain coverage of event-related potentials (ERPs) to test the hypothesis that dlPFC affects dietary self-control through two different mechanisms: attentional filtering and value modulation. Whereas attentional filtering of sensory input should occur early in the decision process, value modulation should occur later on, after the computation of stimulus values begins. Hungry human subjects were asked to make food choices while we measured neural activity using ERP in a natural condition, in which they responded freely and did not exhibit a tendency to regulate their diet, and in a self-control condition, in which they were given a financial incentive to lose weight. We then measured various neural markers associated with the attentional filtering and value modulation mechanisms across the decision period to test for changes in neural activity during the exercise of self-control. Consistent with the hypothesis, we found evidence for top-down attentional filtering early on in the decision period (150–200 ms poststimulus onset) as well as evidence for value modulation later in the process (450–650 ms poststimulus onset). We also found evidence that dlPFC plays a role in the deployment of both mechanisms. PMID:24285897

  5. How disgust facilitates avoidance: an ERP study on attention modulation by threats.

    PubMed

    Liu, Yunzhe; Zhang, Dandan; Luo, Yuejia

    2015-04-01

    This study investigated the attention modulation of disgust in comparison with anger in a dot-probe task. Results indicated a two-stage processing of attention modulation by threats. When participants viewed the cues that were represented by Chinese faces (i.e. the in-group condition), it was found at the early processing stage that an angry face elicited a larger occipital P1 component whereas a disgusted face elicited a smaller P1 for validly than for invalidly cued targets. However, the result pattern was reversed at the later processing stage: the P3 amplitudes were larger for valid disgust cues but were smaller for valid angry cues, when both were compared with invalid cue conditions. In addition, when participants viewed the cues that were represented by foreign faces (i.e. the out-group condition), the attention modulation of disgust/anger diminished at the early stage, whereas enhanced P3 amplitudes were observed in response to validly cued targets in both disgusting and angry conditions at the later stage. The current result implied that although people can perceptually differentiate the emotional categories of out-group faces as accurately as in-group faces, they may still be not able to psychologically understand the subtle differences behind different categories of out-group facial expressions. PMID:24974395

  6. Modulation of Neuronal Responses by Exogenous Attention in Macaque Primary Visual Cortex.

    PubMed

    Wang, Feng; Chen, Minggui; Yan, Yin; Zhaoping, Li; Li, Wu

    2015-09-30

    Visual perception is influenced by attention deployed voluntarily or triggered involuntarily by salient stimuli. Modulation of visual cortical processing by voluntary or endogenous attention has been extensively studied, but much less is known about how involuntary or exogenous attention affects responses of visual cortical neurons. Using implanted microelectrode arrays, we examined the effects of exogenous attention on neuronal responses in the primary visual cortex (V1) of awake monkeys. A bright annular cue was flashed either around the receptive fields of recorded neurons or in the opposite visual field to capture attention. A subsequent grating stimulus probed the cue-induced effects. In a fixation task, when the cue-to-probe stimulus onset asynchrony (SOA) was <240 ms, the cue induced a transient increase of neuronal responses to the probe at the cued location during 40-100 ms after the onset of neuronal responses to the probe. This facilitation diminished and disappeared after repeated presentations of the same cue but recurred for a new cue of a different color. In another task to detect the probe, relative shortening of monkey's reaction times for the validly cued probe depended on the SOA in a way similar to the cue-induced V1 facilitation, and the behavioral and physiological cueing effects remained after repeated practice. Flashing two cues simultaneously in the two opposite visual fields weakened or diminished both the physiological and behavioral cueing effects. Our findings indicate that exogenous attention significantly modulates V1 responses and that the modulation strength depends on both novelty and task relevance of the stimulus. Significance statement: Visual attention can be involuntarily captured by a sudden appearance of a conspicuous object, allowing rapid reactions to unexpected events of significance. The current study discovered a correlate of this effect in monkey primary visual cortex. An abrupt, salient, flash enhanced neuronal

  7. Modulation of Neuronal Responses by Exogenous Attention in Macaque Primary Visual Cortex.

    PubMed

    Wang, Feng; Chen, Minggui; Yan, Yin; Zhaoping, Li; Li, Wu

    2015-09-30

    Visual perception is influenced by attention deployed voluntarily or triggered involuntarily by salient stimuli. Modulation of visual cortical processing by voluntary or endogenous attention has been extensively studied, but much less is known about how involuntary or exogenous attention affects responses of visual cortical neurons. Using implanted microelectrode arrays, we examined the effects of exogenous attention on neuronal responses in the primary visual cortex (V1) of awake monkeys. A bright annular cue was flashed either around the receptive fields of recorded neurons or in the opposite visual field to capture attention. A subsequent grating stimulus probed the cue-induced effects. In a fixation task, when the cue-to-probe stimulus onset asynchrony (SOA) was <240 ms, the cue induced a transient increase of neuronal responses to the probe at the cued location during 40-100 ms after the onset of neuronal responses to the probe. This facilitation diminished and disappeared after repeated presentations of the same cue but recurred for a new cue of a different color. In another task to detect the probe, relative shortening of monkey's reaction times for the validly cued probe depended on the SOA in a way similar to the cue-induced V1 facilitation, and the behavioral and physiological cueing effects remained after repeated practice. Flashing two cues simultaneously in the two opposite visual fields weakened or diminished both the physiological and behavioral cueing effects. Our findings indicate that exogenous attention significantly modulates V1 responses and that the modulation strength depends on both novelty and task relevance of the stimulus. Significance statement: Visual attention can be involuntarily captured by a sudden appearance of a conspicuous object, allowing rapid reactions to unexpected events of significance. The current study discovered a correlate of this effect in monkey primary visual cortex. An abrupt, salient, flash enhanced neuronal

  8. Attentional modulation of background connectivity between ventral visual cortex and the medial temporal lobe.

    PubMed

    Córdova, Natalia I; Tompary, Alexa; Turk-Browne, Nicholas B

    2016-10-01

    Attention prioritizes information that is most relevant to current behavioral goals. This prioritization can be accomplished by amplifying neural responses to goal-relevant information and by strengthening coupling between regions involved in processing this information. Such modulation occurs within and between areas of visual cortex, and relates to behavioral effects of attention on perception. However, attention also has powerful effects on learning and memory behavior, suggesting that similar modulation may occur for memory systems. We used fMRI to investigate this possibility, examining how visual information is prioritized for processing in the medial temporal lobe (MTL). We hypothesized that the way in which ventral visual cortex couples with MTL input structures will depend on the kind of information being attended. Indeed, visual cortex was more coupled with parahippocampal cortex when scenes were attended and more coupled with perirhinal cortex when faces were attended. This switching of MTL connectivity was more pronounced for visual voxels with weak selectivity, suggesting that connectivity might help disambiguate sensory signals. These findings provide an initial window into an attentional mechanism that could have consequences for learning and memory. PMID:27321163

  9. Attentional modulation of background connectivity between ventral visual cortex and the medial temporal lobe.

    PubMed

    Córdova, Natalia I; Tompary, Alexa; Turk-Browne, Nicholas B

    2016-10-01

    Attention prioritizes information that is most relevant to current behavioral goals. This prioritization can be accomplished by amplifying neural responses to goal-relevant information and by strengthening coupling between regions involved in processing this information. Such modulation occurs within and between areas of visual cortex, and relates to behavioral effects of attention on perception. However, attention also has powerful effects on learning and memory behavior, suggesting that similar modulation may occur for memory systems. We used fMRI to investigate this possibility, examining how visual information is prioritized for processing in the medial temporal lobe (MTL). We hypothesized that the way in which ventral visual cortex couples with MTL input structures will depend on the kind of information being attended. Indeed, visual cortex was more coupled with parahippocampal cortex when scenes were attended and more coupled with perirhinal cortex when faces were attended. This switching of MTL connectivity was more pronounced for visual voxels with weak selectivity, suggesting that connectivity might help disambiguate sensory signals. These findings provide an initial window into an attentional mechanism that could have consequences for learning and memory.

  10. Selective Attention to Semantic and Syntactic Features Modulates Sentence Processing Networks in Anterior Temporal Cortex

    PubMed Central

    Rogalsky, Corianne

    2009-01-01

    Numerous studies have identified an anterior temporal lobe (ATL) region that responds preferentially to sentence-level stimuli. It is unclear, however, whether this activity reflects a response to syntactic computations or some form of semantic integration. This distinction is difficult to investigate with the stimulus manipulations and anomaly detection paradigms traditionally implemented. The present functional magnetic resonance imaging study addresses this question via a selective attention paradigm. Subjects monitored for occasional semantic anomalies or occasional syntactic errors, thus directing their attention to semantic integration, or syntactic properties of the sentences. The hemodynamic response in the sentence-selective ATL region (defined with a localizer scan) was examined during anomaly/error-free sentences only, to avoid confounds due to error detection. The majority of the sentence-specific region of interest was equally modulated by attention to syntactic or compositional semantic features, whereas a smaller subregion was only modulated by the semantic task. We suggest that the sentence-specific ATL region is sensitive to both syntactic and integrative semantic functions during sentence processing, with a smaller portion of this area preferentially involved in the later. This study also suggests that selective attention paradigms may be effective tools to investigate the functional diversity of networks involved in sentence processing. PMID:18669589

  11. Modulation of attention network activation under antidepressant agents in healthy subjects.

    PubMed

    Graf, Heiko; Abler, Birgit; Hartmann, Antonie; Metzger, Coraline D; Walter, Martin

    2013-07-01

    While antidepressants are supposed to exert similar effects on mood and drive via various mechanisms of action, diverging effects are observed regarding side-effects and accordingly on neural correlates of motivation, emotion, reward and salient stimuli processing as a function of the drugs impact on neurotransmission. In the context of erotic stimulation, a unidirectional modulation of attentional functioning despite opposite effects on sexual arousal has been suggested for the selective serotonin reuptake-inhibitor (SSRI) paroxetine and the selective dopamine and noradrenaline reuptake-inhibitor (SDNRI) bupropion. To further elucidate the effects of antidepressant-related alterations of neural attention networks, we investigated 18 healthy males under subchronic administration (7 d) of paroxetine (20 mg), bupropion (150 mg) and placebo within a randomized placebo-controlled cross-over double-blind functional magnetic resonance imaging (fMRI) design during an established preceding attention task. Neuropsychological effects beyond the fMRI-paradigm were assessed by measuring alertness and divided attention. Comparing preceding attention periods of salient vs. neutral pictures, we revealed congruent effects of both drugs vs. placebo within the anterior midcingulate cortex, dorsolateral prefrontal cortex, anterior prefrontal cortex, superior temporal gyrus, anterior insula and the thalamus. Relatively decreased activation in this network was paralleled by slower reaction times in the divided attention task in both verum conditions compared to placebo. Our results suggest similar effects of antidepressant treatments on behavioural and neural attentional functioning by diverging neurochemical pathways. Concurrent alterations of brain regions within a fronto-parietal and cingulo-opercular attention network for top-down control could point to basic neural mechanisms of antidepressant action irrespective of receptor profiles. PMID:23200084

  12. Attention modulations on the perception of social hierarchy at distinct temporal stages: an electrophysiological investigation.

    PubMed

    Feng, Chunliang; Tian, Tengxiang; Feng, Xue; Luo, Yue-Jia

    2015-04-01

    Recent behavioral and neuroscientific studies have revealed the preferential processing of superior-hierarchy cues. However, it remains poorly understood whether top-down controlled mechanisms modulate temporal dynamics of neurocognitive substrates underlying the preferential processing of these biologically and socially relevant cues. This was investigated in the current study by recording event-related potentials from participants who were presented with superior or inferior social hierarchy. Participants performed a hierarchy-judgment task that required attention to hierarchy cues or a gender-judgment task that withdrew their attention from these cues. Superior-hierarchy cues evoked stronger neural responses than inferior-hierarchy cues at both early (N170/N200) and late (late positive potential, LPP) temporal stages. Notably, the modulations of top-down attention were identified on the LPP component, such that superior-hierarchy cues evoked larger LPP amplitudes than inferior-hierarchy cues only in the attended condition; whereas the modulations of the N170/N200 component by hierarchy cues were evident in both attended and unattended conditions. These findings suggest that the preferential perception of superior-hierarchy cues involves both relatively automatic attentional bias at the early temporal stage as well as flexible and voluntary cognitive evaluation at the late temporal stage. Finally, these hierarchy-related effects were absent when participants were shown the same stimuli which, however, were not associated with social-hierarchy information in a non-hierarchy task (Experiment 2), suggesting that effects of social hierarchy at early and late temporal stages could not be accounted for by differences in physical attributes between these social cues. PMID:25681738

  13. Attention modulates cortical processing of pitch feedback errors in voice control.

    PubMed

    Hu, Huijing; Liu, Ying; Guo, Zhiqiang; Li, Weifeng; Liu, Peng; Chen, Shaozhen; Liu, Hanjun

    2015-01-01

    Considerable evidence has shown that unexpected alterations in auditory feedback elicit fast compensatory adjustments in vocal production. Although generally thought to be involuntary in nature, whether these adjustments can be influenced by attention remains unknown. The present event-related potential (ERP) study aimed to examine whether neurobehavioral processing of auditory-vocal integration can be affected by attention. While sustaining a vowel phonation and hearing pitch-shifted feedback, participants were required to either ignore the pitch perturbations, or attend to them with low (counting the number of perturbations) or high attentional load (counting the type of perturbations). Behavioral results revealed no systematic change of vocal response to pitch perturbations irrespective of whether they were attended or not. At the level of cortex, there was an enhancement of P2 response to attended pitch perturbations in the low-load condition as compared to when they were ignored. In the high-load condition, however, P2 response did not differ from that in the ignored condition. These findings provide the first neurophysiological evidence that auditory-motor integration in voice control can be modulated as a function of attention at the level of cortex. Furthermore, this modulatory effect does not lead to a general enhancement but is subject to attentional load.

  14. The Primary Visual Cortex Is Differentially Modulated by Stimulus-Driven and Top-Down Attention

    PubMed Central

    Bekisz, Marek; Bogdan, Wojciech; Ghazaryan, Anaida; Waleszczyk, Wioletta J.; Kublik, Ewa; Wróbel, Andrzej

    2016-01-01

    Selective attention can be focused either volitionally, by top-down signals derived from task demands, or automatically, by bottom-up signals from salient stimuli. Because the brain mechanisms that underlie these two attention processes are poorly understood, we recorded local field potentials (LFPs) from primary visual cortical areas of cats as they performed stimulus-driven and anticipatory discrimination tasks. Consistent with our previous observations, in both tasks, we found enhanced beta activity, which we have postulated may serve as an attention carrier. We characterized the functional organization of task-related beta activity by (i) cortical responses (EPs) evoked by electrical stimulation of the optic chiasm and (ii) intracortical LFP correlations. During the anticipatory task, peripheral stimulation that was preceded by high-amplitude beta oscillations evoked large-amplitude EPs compared with EPs that followed low-amplitude beta. In contrast, during the stimulus-driven task, cortical EPs preceded by high-amplitude beta oscillations were, on average, smaller than those preceded by low-amplitude beta. Analysis of the correlations between the different recording sites revealed that beta activation maps were heterogeneous during the bottom-up task and homogeneous for the top-down task. We conclude that bottom-up attention activates cortical visual areas in a mosaic-like pattern, whereas top-down attentional modulation results in spatially homogeneous excitation. PMID:26730705

  15. What we observe is biased by what other people tell us: beliefs about the reliability of gaze behavior modulate attentional orienting to gaze cues.

    PubMed

    Wiese, Eva; Wykowska, Agnieszka; Müller, Hermann J

    2014-01-01

    For effective social interactions with other people, information about the physical environment must be integrated with information about the interaction partner. In order to achieve this, processing of social information is guided by two components: a bottom-up mechanism reflexively triggered by stimulus-related information in the social scene and a top-down mechanism activated by task-related context information. In the present study, we investigated whether these components interact during attentional orienting to gaze direction. In particular, we examined whether the spatial specificity of gaze cueing is modulated by expectations about the reliability of gaze behavior. Expectations were either induced by instruction or could be derived from experience with displayed gaze behavior. Spatially specific cueing effects were observed with highly predictive gaze cues, but also when participants merely believed that actually non-predictive cues were highly predictive. Conversely, cueing effects for the whole gazed-at hemifield were observed with non-predictive gaze cues, and spatially specific cueing effects were attenuated when actually predictive gaze cues were believed to be non-predictive. This pattern indicates that (i) information about cue predictivity gained from sampling gaze behavior across social episodes can be incorporated in the attentional orienting to social cues, and that (ii) beliefs about gaze behavior modulate attentional orienting to gaze direction even when they contradict information available from social episodes.

  16. Influence of Compulsivity of Drug Abuse on Dopaminergic Modulation of Attentional Bias in Stimulant Dependence

    PubMed Central

    Ersche, Karen D.; Bullmore, Edward T.; Craig, Kevin J.; Shabbir, Shaila S.; Abbott, Sanja; Müller, Ulrich; Ooi, Cinly; Suckling, John; Barnes, Anna; Sahakian, Barbara J.; Merlo-Pich, Emilio V.; Robbins, Trevor W.

    2013-01-01

    effects on attentional bias, its brain functional representation, and its short-term modulation by dopaminergic challenges. PMID:20530013

  17. Post-perceptual processing during the attentional blink is modulated by inter-trial task expectancies

    PubMed Central

    Sy, Jocelyn L.; Elliott, James C.; Giesbrecht, Barry

    2013-01-01

    The selective processing of goal-relevant information depends on an attention system that can flexibly adapt to changing task demands and expectations. Evidence from visual search tasks indicates that the perceptual selectivity of attention increases when the bottom-up demands of the task increase and when the expectations about task demands engendered by trial history are violated. Evidence from studies of the attentional blink (AB), which measures the temporal dynamics of attention, also indicates that perceptual selectivity during the AB is increased if the bottom-up task demands are increased. The present work tested whether expectations about task demands engendered by trial history also modulate perceptual selectivity during the AB. Two experiments tested the extent to which inter-trial switches in task demands reduced post-perceptual processing of targets presented during the AB. Experiment 1 indexed post-perceptual processing using the event-related potential (ERP) technique to isolate the context sensitive N400 ERP component evoked by words presented during the AB. Experiment 2 indexed post-perceptual processing using behavioral performance to determine the extent to which personal names survive the AB. The results of both experiments revealed that both electrophysiological (Exp. 1) and behavioral (Exp. 2) indices of post-perceptual processing were attenuated when consecutive trials differed in terms of their perceptual demands. The results are consistent with the notion that the selectivity of attention during the AB is modulated not only by within-trial task demands, but also can be flexibly determined by trial-by-trial expectations. PMID:24115924

  18. Infants' Temperament and Mothers', and Fathers' Depression Predict Infants' Attention to Objects Paired with Emotional Faces.

    PubMed

    Aktar, Evin; Mandell, Dorothy J; de Vente, Wieke; Majdandžić, Mirjana; Raijmakers, Maartje E J; Bögels, Susan M

    2016-07-01

    Between 10 and 14 months, infants gain the ability to learn about unfamiliar stimuli by observing others' emotional reactions to those stimuli, so called social referencing (SR). Joint processing of emotion and head/gaze direction is essential for SR. This study tested emotion and head/gaze direction effects on infants' attention via pupillometry in the period following the emergence of SR. Pupil responses of 14-to-17-month-old infants (N = 57) were measured during computerized presentations of unfamiliar objects alone, before-and-after being paired with emotional (happy, sad, fearful vs. neutral) faces gazing towards (vs. away) from objects. Additionally, the associations of infants' temperament, and parents' negative affect/depression/anxiety with infants' pupil responses were explored. Both mothers and fathers of participating infants completed questionnaires about their negative affect, depression and anxiety symptoms and their infants' negative temperament. Infants allocated more attention (larger pupils) to negative vs. neutral faces when the faces were presented alone, while they allocated less attention to objects paired with emotional vs. neutral faces independent of head/gaze direction. Sad (but not fearful) temperament predicted more attention to emotional faces. Infants' sad temperament moderated the associations of mothers' depression (but not anxiety) with infants' attention to objects. Maternal depression predicted more attention to objects paired with emotional expressions in infants low in sad temperament, while it predicted less attention in infants high in sad temperament. Fathers' depression (but not anxiety) predicted more attention to objects paired with emotional expressions independent of infants' temperament. We conclude that infants' own temperamental dispositions for sadness, and their exposure to mothers' and fathers' depressed moods may influence infants' attention to emotion-object associations in social learning contexts. PMID

  19. A New Test of Attention in Listening (TAIL) Predicts Auditory Performance

    PubMed Central

    Zhang, Yu-Xuan; Barry, Johanna G.; Moore, David R.; Amitay, Sygal

    2012-01-01

    Attention modulates auditory perception, but there are currently no simple tests that specifically quantify this modulation. To fill the gap, we developed a new, easy-to-use test of attention in listening (TAIL) based on reaction time. On each trial, two clearly audible tones were presented sequentially, either at the same or different ears. The frequency of the tones was also either the same or different (by at least two critical bands). When the task required same/different frequency judgments, presentation at the same ear significantly speeded responses and reduced errors. A same/different ear (location) judgment was likewise facilitated by keeping tone frequency constant. Perception was thus influenced by involuntary orienting of attention along the task-irrelevant dimension. When information in the two stimulus dimensions were congruent (same-frequency same-ear, or different-frequency different-ear), response was faster and more accurate than when they were incongruent (same-frequency different-ear, or different-frequency same-ear), suggesting the involvement of executive control to resolve conflicts. In total, the TAIL yielded five independent outcome measures: (1) baseline reaction time, indicating information processing efficiency, (2) involuntary orienting of attention to frequency and (3) location, and (4) conflict resolution for frequency and (5) location. Processing efficiency and conflict resolution accounted for up to 45% of individual variances in the low- and high-threshold variants of three psychoacoustic tasks assessing temporal and spectral processing. Involuntary orientation of attention to the irrelevant dimension did not correlate with perceptual performance on these tasks. Given that TAIL measures are unlikely to be limited by perceptual sensitivity, we suggest that the correlations reflect modulation of perceptual performance by attention. The TAIL thus has the power to identify and separate contributions of different components of attention

  20. Children's cortisol and salivary alpha-amylase interact to predict attention bias to threatening stimuli.

    PubMed

    Ursache, Alexandra; Blair, Clancy

    2015-01-01

    Physiological responses to threat occur through both the autonomic nervous system (ANS) and the hypothalamic pituitary adrenal (HPA) axis. Activity in these systems can be measured through salivary alpha-amylase (sAA) and salivary cortisol, respectively. Theoretical work and empirical studies have suggested the importance of examining the coordination of these systems in relation to cognitive functioning and behavior problems. Less is known, however, about whether these systems interactively predict more automatic aspects of attention processing such as attention toward emotionally salient threatening stimuli. We used a dot probe task to assess attention bias toward threatening stimuli in 347 kindergarten children. Cortisol and sAA were assayed from saliva samples collected prior to children's participation in assessments on a subsequent day. Using regression analyses, we examined relations of sAA and cortisol to attention bias. Results indicate that cortisol and sAA interact in predicting attention bias. Higher levels of cortisol predicted greater bias toward threat for children who had high levels of sAA, but predicted greater bias away from threat for children who had low levels of sAA. These results suggest that greater symmetry in HPA and ANS functioning is associated with greater reliance on automatic attention processes in the face of threat.

  1. Spatial scale, rather than nature of task or locomotion, modulates the spatial reference frame of attention

    PubMed Central

    Jiang, Yuhong V.; Won, Bo-Yeong

    2015-01-01

    Visuospatial attention is strongly biased to locations that frequently contained a search target before. However, the function of this bias depends on the reference frame in which attended locations are coded. Previous research has shown a striking difference between tasks administered on a computer monitor and in a large environment, with the former inducing viewer-centered learning and the latter environment-centered learning. Why does environment-centered learning fail on a computer? Here we tested three possibilities: differences in spatial scale, nature of task, and locomotion may influence the reference frame of attention. Participants searched for a target on a monitor placed flat on a stand. On each trial they stood at a different location around the monitor. The target was frequently located in a fixed area of the monitor, but changes in participants’ perspective rendered this area random relative to the participants. Under incidental learning conditions participants failed to acquire environment-centered learning even when (i) the task and display resembled the large-scale task, and (ii) the search task required locomotion. The difficulty in inducing environment-centered learning on a computer underscores the egocentric nature of visual attention. It supports the idea that spatial scale modulates the reference frame of attention. PMID:25867510

  2. Rhythm and Attention: Does the Beat Position of a Visual or Auditory Regular Pulse Modulate T2 Detection in the Attentional Blink?

    PubMed

    Bermeitinger, Christina; Frings, Christian

    2015-01-01

    The attentional blink (AB) is one impressive demonstration of limited attentional capacities in time: a second target (T2) is often missed when it should be detected within 200-600 ms after a first target. According to the dynamic attending theory, attention cycles oscillatory. Regular rhythms (i.e., pulses) should evoke expectations regarding the point of the next occurrence of a tone/element in the rhythm. At this point, more attentional resources should be provided. Thus, if rhythmic information can be used to optimize attentional release, we assume a modulation of the AB when an additional rhythm is given. We tested this idea in two experiments with a visual (Experiment 1) or an auditory (Experiment 2) rhythm. We found large AB effects. However, the rhythm did not modulate the AB. If the rhythm had an influence at all, then Experiment 2 showed that an auditory rhythm (or stimulus) falling on T2 might generally boost visual processing, irrespective of attentional resources as indexed by the AB paradigm. Our experiments suggest that oscillatory cycling attention does not affect temporal selection as tapped in the AB paradigm. PMID:26648899

  3. Rhythm and Attention: Does the Beat Position of a Visual or Auditory Regular Pulse Modulate T2 Detection in the Attentional Blink?

    PubMed Central

    Bermeitinger, Christina; Frings, Christian

    2015-01-01

    The attentional blink (AB) is one impressive demonstration of limited attentional capacities in time: a second target (T2) is often missed when it should be detected within 200–600 ms after a first target. According to the dynamic attending theory, attention cycles oscillatory. Regular rhythms (i.e., pulses) should evoke expectations regarding the point of the next occurrence of a tone/element in the rhythm. At this point, more attentional resources should be provided. Thus, if rhythmic information can be used to optimize attentional release, we assume a modulation of the AB when an additional rhythm is given. We tested this idea in two experiments with a visual (Experiment 1) or an auditory (Experiment 2) rhythm. We found large AB effects. However, the rhythm did not modulate the AB. If the rhythm had an influence at all, then Experiment 2 showed that an auditory rhythm (or stimulus) falling on T2 might generally boost visual processing, irrespective of attentional resources as indexed by the AB paradigm. Our experiments suggest that oscillatory cycling attention does not affect temporal selection as tapped in the AB paradigm. PMID:26648899

  4. A Candidate for the Attentional Bottleneck: Set-Size Specific Modulation of the Right TPJ during Attentive Enumeration

    ERIC Educational Resources Information Center

    Vetter, Petra; Butterworth, Brian; Bahrami, Bahador

    2011-01-01

    Several recent behavioral studies have shown that the enumeration of a small number of items (a process termed "subitizing") depends on the availability of attentional resources and is not a preattentive process as previously thought. Here we studied the neural correlates of visual enumeration under different attentional loads in a dual-task…

  5. Modulation of auditory spatial attention by visual emotional cues: differential effects of attentional engagement and disengagement for pleasant and unpleasant cues.

    PubMed

    Harrison, Neil R; Woodhouse, Rob

    2016-05-01

    Previous research has demonstrated that threatening, compared to neutral pictures, can bias attention towards non-emotional auditory targets. Here we investigated which subcomponents of attention contributed to the influence of emotional visual stimuli on auditory spatial attention. Participants indicated the location of an auditory target, after brief (250 ms) presentation of a spatially non-predictive peripheral visual cue. Responses to targets were faster at the location of the preceding visual cue, compared to at the opposite location (cue validity effect). The cue validity effect was larger for targets following pleasant and unpleasant cues compared to neutral cues, for right-sided targets. For unpleasant cues, the crossmodal cue validity effect was driven by delayed attentional disengagement, and for pleasant cues, it was driven by enhanced engagement. We conclude that both pleasant and unpleasant visual cues influence the distribution of attention across modalities and that the associated attentional mechanisms depend on the valence of the visual cue. PMID:26842012

  6. Attentional modulation in the detection of irrelevant deviance: a simultaneous ERP/fMRI study.

    PubMed

    Sabri, M; Liebenthal, E; Waldron, E J; Medler, D A; Binder, J R

    2006-05-01

    Little is known about the neural mechanisms that control attentional modulation of deviance detection in the auditory modality. In this study, we manipulated the difficulty of a primary task to test the relation between task difficulty and the detection of infrequent, task-irrelevant deviant (D) tones (1,300 Hz) presented among repetitive standard (S) tones (1,000 Hz). Simultaneous functional magnetic resonance imaging (fMRI)/event-related potentials (ERPs) were recorded from 21 subjects performing a two-alternative forced-choice duration discrimination task (short and long tones of equal probability). The duration of the short tone was always 50 msec. The duration of the long tone was 100 msec in the easy task and 60 msec in the difficult task. As expected, response accuracy decreased and response time (RT) increased in the difficult compared with the easy task. Performance was also poorer for D than for S tones, indicating distraction by task-irrelevant frequency information on trials involving D tones. In the difficult task, an amplitude increase was observed in the difference waves for N1 and P3a, ERP components associated with increased attention to deviant sounds. The mismatch negativity (MMN) response, associated with passive deviant detection, was larger in the easy task, demonstrating the susceptibility of this component to attentional manipulations. The fMRI contrast D > S in the difficult task revealed activation on the right superior temporal gyrus (STG) and extending ventrally into the superior temporal sulcus, suggesting this region's involvement in involuntary attention shifting toward unattended, infrequent sounds. Conversely, passive deviance detection, as reflected by the MMN, was associated with more dorsal activation on the STG. These results are consistent with the view that the dorsal STG region is responsive to mismatches between the memory trace of the standard and the incoming deviant sound, whereas the ventral STG region is activated by

  7. Reward sensitivity predicts ice cream-related attentional bias assessed by inattentional blindness.

    PubMed

    Li, Xiaoming; Tao, Qian; Fang, Ya; Cheng, Chen; Hao, Yangyang; Qi, Jianjun; Li, Yu; Zhang, Wei; Wang, Ying; Zhang, Xiaochu

    2015-06-01

    The cognitive mechanism underlying the association between individual differences in reward sensitivity and food craving is unknown. The present study explored the mechanism by examining the role of reward sensitivity in attentional bias toward ice cream cues. Forty-nine college students who displayed high level of ice cream craving (HICs) and 46 who displayed low level of ice cream craving (LICs) performed an inattentional blindness (IB) task which was used to assess attentional bias for ice cream. In addition, reward sensitivity and coping style were assessed by the Behavior Inhibition System/Behavior Activation System Scales and Simplified Coping Style Questionnaire. Results showed significant higher identification rate of the critical stimulus in the HICs than LICs, suggesting greater attentional bias for ice cream in the HICs. It was indicated that attentional bias for food cues persisted even under inattentional condition. Furthermore, a significant correlation was found between the attentional bias and reward sensitivity after controlling for coping style, and reward sensitivity predicted attentional bias for food cues. The mediation analyses showed that attentional bias mediated the relationship between reward sensitivity and food craving. Those findings suggest that the association between individual differences in reward sensitivity and food craving may be attributed to attentional bias for food-related cues.

  8. Attentional blink is hierarchically modulated by phonological, morphological, semantic and lexical connections between two Chinese characters.

    PubMed

    Cao, Hong-Wen; Jin, Kai-Bin; Li, Chao-Yi; Yan, Hong-Mei

    2014-01-01

    The ability to identify the second of two targets (T2) is impaired if that target is presented less than ∼500 ms after the first (T1). This transient deficit is known as attentional blink (AB). Previous studies have suggested that the magnitude of the AB effect can be modulated by manipulating the allocation of attentional resources to T1 or T2. However, few experiments have used Chinese characters and words to explore this phenomenon. The existence of lexical, semantic, phonological and morphological connections between Chinese characters has been well established, and understanding these connections may improve our knowledge of reading Chinese. In this study, we employed varying connections between T1 and T2 and examined how these connections modulate the AB effect. We found that the strongest AB was observed when the two Chinese characters were completely unrelated, while the AB was reduced when T1 and T2 were phonologically, orthographically or semantically related and was almost completely eliminated when T1 and T2 were united in a lexical phrase. The order of activation between Chinese characters was identified as follows: (a) lexical phrases, (b) semantic connection, (c) morphological connection, (d) phonological connection and (e) unrelated words.

  9. Mental workload prediction based on attentional resource allocation and information processing.

    PubMed

    Xiao, Xu; Wanyan, Xiaoru; Zhuang, Damin

    2015-01-01

    Mental workload is an important component in complex human-machine systems. The limited applicability of empirical workload measures produces the need for workload modeling and prediction methods. In the present study, a mental workload prediction model is built on the basis of attentional resource allocation and information processing to ensure pilots' accuracy and speed in understanding large amounts of flight information on the cockpit display interface. Validation with an empirical study of an abnormal attitude recovery task showed that this model's prediction of mental workload highly correlated with experimental results. This mental workload prediction model provides a new tool for optimizing human factors interface design and reducing human errors. PMID:26406085

  10. Attention selectively modulates cortical entrainment in different regions of the speech spectrum.

    PubMed

    Baltzell, Lucas S; Horton, Cort; Shen, Yi; Richards, Virginia M; D'Zmura, Michael; Srinivasan, Ramesh

    2016-08-01

    Recent studies have uncovered a neural response that appears to track the envelope of speech, and have shown that this tracking process is mediated by attention. It has been argued that this tracking reflects a process of phase-locking to the fluctuations of stimulus energy, ensuring that this energy arrives during periods of high neuronal excitability. Because all acoustic stimuli are decomposed into spectral channels at the cochlea, and this spectral decomposition is maintained along the ascending auditory pathway and into auditory cortex, we hypothesized that the overall stimulus envelope is not as relevant to cortical processing as the individual frequency channels; attention may be mediating envelope tracking differentially across these spectral channels. To test this we reanalyzed data reported by Horton et al. (2013), where high-density EEG was recorded while adults attended to one of two competing naturalistic speech streams. In order to simulate cochlear filtering, the stimuli were passed through a gammatone filterbank, and temporal envelopes were extracted at each filter output. Following Horton et al. (2013), the attended and unattended envelopes were cross-correlated with the EEG, and local maxima were extracted at three different latency ranges corresponding to distinct peaks in the cross-correlation function (N1, P2, and N2). We found that the ratio between the attended and unattended cross-correlation functions varied across frequency channels in the N1 latency range, consistent with the hypothesis that attention differentially modulates envelope-tracking activity across spectral channels. PMID:27195825

  11. Emotional modulation of the attentional blink and the relation to interpersonal reactivity

    PubMed Central

    Kanske, Philipp; Schönfelder, Sandra; Wessa, Michèle

    2013-01-01

    The extent of the attentional blink effect on detection rates in rapid serial visual presentations is modulated by the emotionality of the stimuli. Emotionally salient stimuli are detected more often, even if presented in the attentional blink period, and elicit an enlarged P3 response, which has been interpreted as enhanced consolidation. This effect correlates with individual differences in trait affectivity such as anxiety or dysphoria. Here, we ask if it is also related to the capacity to detect emotions in others, i.e., to interpersonal social traits. We therefore presented emotional and neutral images depicting social scenes as targets in an attentional blink design and measured detection rates and event-related potentials. In addition, we recorded self-reports of empathy as measured by the Interpersonal Reactivity Index. The results show enhanced performance for emotional stimuli and increased P3 amplitudes, which correlated with individual differences in empathy. The data suggest that self-reported empathy goes along with enhanced processing of emotion in social stimuli, even under stimulus conditions that are suboptimal for conscious target detection. PMID:24130525

  12. Trait Mindfulness Predicts Efficient Top-Down Attention to and Discrimination of Facial Expressions.

    PubMed

    Quaglia, Jordan T; Goodman, Robert J; Brown, Kirk Warren

    2016-06-01

    In social situations, skillful regulation of emotion and behavior depends on efficiently discerning others' emotions. Identifying factors that promote timely and accurate discernment of facial expressions can therefore advance understanding of social emotion regulation and behavior. The present research examined whether trait mindfulness predicts neural and behavioral markers of early top-down attention to, and efficient discrimination of, socioemotional stimuli. Attention-based event-related potentials (ERPs) and behavioral responses were recorded while participants (N = 62; White; 67% female; Mage = 19.09 years, SD = 2.14 years) completed an emotional go/no-go task involving happy, neutral, and fearful facial expressions. Mindfulness predicted larger (more negative) N100 and N200 ERP amplitudes to both go and no-go stimuli. Mindfulness also predicted faster response time that was not attributable to a speed-accuracy trade-off. Significant relations held after accounting for attentional control or social anxiety. This study adds neurophysiological support for foundational accounts that mindfulness entails moment-to-moment attention with lower tendencies toward habitual patterns of responding. Mindfulness may enhance the quality of social behavior in socioemotional contexts by promoting efficient top-down attention to and discrimination of others' emotions, alongside greater monitoring and inhibition of automatic response tendencies. PMID:25676934

  13. Trait Mindfulness Predicts Efficient Top-Down Attention to and Discrimination of Facial Expressions.

    PubMed

    Quaglia, Jordan T; Goodman, Robert J; Brown, Kirk Warren

    2016-06-01

    In social situations, skillful regulation of emotion and behavior depends on efficiently discerning others' emotions. Identifying factors that promote timely and accurate discernment of facial expressions can therefore advance understanding of social emotion regulation and behavior. The present research examined whether trait mindfulness predicts neural and behavioral markers of early top-down attention to, and efficient discrimination of, socioemotional stimuli. Attention-based event-related potentials (ERPs) and behavioral responses were recorded while participants (N = 62; White; 67% female; Mage = 19.09 years, SD = 2.14 years) completed an emotional go/no-go task involving happy, neutral, and fearful facial expressions. Mindfulness predicted larger (more negative) N100 and N200 ERP amplitudes to both go and no-go stimuli. Mindfulness also predicted faster response time that was not attributable to a speed-accuracy trade-off. Significant relations held after accounting for attentional control or social anxiety. This study adds neurophysiological support for foundational accounts that mindfulness entails moment-to-moment attention with lower tendencies toward habitual patterns of responding. Mindfulness may enhance the quality of social behavior in socioemotional contexts by promoting efficient top-down attention to and discrimination of others' emotions, alongside greater monitoring and inhibition of automatic response tendencies.

  14. Attention attraction in an ophthalmic diagnostic device using sound-modulated fixation targets.

    PubMed

    Gramatikov, Boris I; Rangarajan, Shreya; Irsch, Kristina; Guyton, David L

    2016-08-01

    This study relates to eye fixation systems with combined optical and audio systems. Many devices for eye diagnostics and some devices for eye therapeutics require the patient to fixate on a small target for a certain period of time, during which the eyes do not move and data from substructures of one or both eyes are acquired and analyzed. With young pediatric patients, a monotonously blinking target is not sufficient to retain attention steadily. We developed a method for modulating the intensity of a point fixation target using sounds appropriate to the child's age and preference. The method was realized as a subsystem of a Pediatric Vision Screener which employs retinal birefringence scanning for detection of central fixation. Twenty-one children, age 2-18, were studied. Modulation of the fixation target using sounds ensured the eye fixated on the target, and with appropriate choice of sounds, performed significantly better than a monotonously blinking target accompanied by a plain beep. The method was particularly effective with children of ages up to 10, after which its benefit disappeared. Typical applications of target modulation would be as supplemental subsystems in pediatric ophthalmic diagnostic devices, such as scanning laser ophthalmoscopes, optical coherence tomography units, retinal birefringence scanners, fundus cameras, and perimeters.

  15. Attention attraction in an ophthalmic diagnostic device using sound-modulated fixation targets.

    PubMed

    Gramatikov, Boris I; Rangarajan, Shreya; Irsch, Kristina; Guyton, David L

    2016-08-01

    This study relates to eye fixation systems with combined optical and audio systems. Many devices for eye diagnostics and some devices for eye therapeutics require the patient to fixate on a small target for a certain period of time, during which the eyes do not move and data from substructures of one or both eyes are acquired and analyzed. With young pediatric patients, a monotonously blinking target is not sufficient to retain attention steadily. We developed a method for modulating the intensity of a point fixation target using sounds appropriate to the child's age and preference. The method was realized as a subsystem of a Pediatric Vision Screener which employs retinal birefringence scanning for detection of central fixation. Twenty-one children, age 2-18, were studied. Modulation of the fixation target using sounds ensured the eye fixated on the target, and with appropriate choice of sounds, performed significantly better than a monotonously blinking target accompanied by a plain beep. The method was particularly effective with children of ages up to 10, after which its benefit disappeared. Typical applications of target modulation would be as supplemental subsystems in pediatric ophthalmic diagnostic devices, such as scanning laser ophthalmoscopes, optical coherence tomography units, retinal birefringence scanners, fundus cameras, and perimeters. PMID:27245750

  16. Losses as modulators of attention: review and analysis of the unique effects of losses over gains.

    PubMed

    Yechiam, Eldad; Hochman, Guy

    2013-03-01

    It has been shown that in certain situations losses exert a stronger effect on behavior than respective gains, and this has been commonly explained by the argument that losses are given more weight in people's decisions than respective gains. However, although much is understood about the effect of losses on cognitive processes and behavior, 2 major inconsistencies remain. First, recent empirical evidence fails to demonstrate that people avoid incentive structures that carry equivalent gains and losses. Second, findings in experience-based decision tasks indicate that following losses, increased arousal is observed simultaneously with no behavioral loss aversion. To account for these findings, we developed an attention-allocation model as a comprehensive framework for the effect of losses. According to this model losses increase on-task attention, thereby enhancing the sensitivity to the reinforcement structure. In the current article we examine whether this model can account for a broad range of empirical phenomena involving losses. We show that as predicted by the attentional model, asymmetric effects of losses on behavior emerge where gains and losses are presented separately but not concurrently. Yet, even in the absence of loss aversion, losses have distinct effects on performance, arousal, frontal cortical activation, and behavioral consistency. The attentional model of losses thus explains some of the main inconsistencies in previous studies of the effect of losses. PMID:22823738

  17. Losses as modulators of attention: review and analysis of the unique effects of losses over gains.

    PubMed

    Yechiam, Eldad; Hochman, Guy

    2013-03-01

    It has been shown that in certain situations losses exert a stronger effect on behavior than respective gains, and this has been commonly explained by the argument that losses are given more weight in people's decisions than respective gains. However, although much is understood about the effect of losses on cognitive processes and behavior, 2 major inconsistencies remain. First, recent empirical evidence fails to demonstrate that people avoid incentive structures that carry equivalent gains and losses. Second, findings in experience-based decision tasks indicate that following losses, increased arousal is observed simultaneously with no behavioral loss aversion. To account for these findings, we developed an attention-allocation model as a comprehensive framework for the effect of losses. According to this model losses increase on-task attention, thereby enhancing the sensitivity to the reinforcement structure. In the current article we examine whether this model can account for a broad range of empirical phenomena involving losses. We show that as predicted by the attentional model, asymmetric effects of losses on behavior emerge where gains and losses are presented separately but not concurrently. Yet, even in the absence of loss aversion, losses have distinct effects on performance, arousal, frontal cortical activation, and behavioral consistency. The attentional model of losses thus explains some of the main inconsistencies in previous studies of the effect of losses.

  18. Sustained and transient attentional processes modulate neural predictors of memory encoding in consecutive time periods.

    PubMed

    Padovani, Tullia; Koenig, Thomas; Eckstein, Doris; Perrig, Walter J

    2013-07-01

    Memory formation is commonly thought to rely on brain activity following an event. Yet, recent research has shown that even brain activity previous to an event can predict later recollection (subsequent memory effect, SME). In order to investigate the attentional sources of the SME, event-related potentials (ERPs) elicited by task cues preceding target words were recorded in a switched task paradigm that was followed by a surprise recognition test. Stay trials, that is, those with the same task as the previous trial, were contrasted with switch trials, which included a task switch compared to the previous trial. The underlying assumption was that sustained attention would be dominant in stay trials and that transient attentional reconfiguration processes would be dominant in switch trials. To determine the SME, local and global statistics of scalp electric fields were used to identify differences between subsequently remembered and forgotten items. Results showed that the SME in stay trials occurred in a time window from 2 to 1 sec before target onset, whereas the SME in switch trials occurred subsequently, in a time window from 1 to 0 sec before target onset. Both SMEs showed a frontal negativity resembling the topography of previously reported effects, which suggests that sustained and transient attentional processes contribute to the prestimulus SME in consecutive time periods. PMID:24381815

  19. Hallucinations predict attentional improvements with rivastigmine in dementia with lewy bodies.

    PubMed

    McKeith, Ian G; Wesnes, Keith A; Perry, Elaine; Ferrara, Roberto

    2004-01-01

    The aim of this analysis of the effects of cholinergic therapy in dementia with Lewy bodies was to determine whether rivastigmine-induced benefits in attention and memory could be predicted by the presence of visual hallucinations. At study entry, 74% of patients were hallucinators and 26% were non-hallucinators. The population was analyzed for two-factor scores: power of attention (PoA) and quality of memory (QoM). A significant effect over placebo on PoA was observed in hallucinators at weeks 12 (p = 0.023) and 20 (p = 0.0019), while no treatment effects were seen in non-hallucinators. Significant treatment effects on QoM were not observed in either subgroup. Visual hallucinations predicted greater improvements in PoA, but not QoM. This may reflect the greater cholinergic deficits in areas of the brain responsible for visual hallucinations, offering greater potential for attentional improvement. PMID:15087584

  20. Foundational Tuning: How Infants' Attention to Speech Predicts Language Development

    ERIC Educational Resources Information Center

    Vouloumanos, Athena; Curtin, Suzanne

    2014-01-01

    Orienting biases for speech may provide a foundation for language development. Although human infants show a bias for listening to speech from birth, the relation of a speech bias to later language development has not been established. Here, we examine whether infants' attention to speech directly predicts expressive vocabulary. Infants…

  1. Speed of Inhibition Predicts Teacher--Rated Medication Response in Boys with Attention Deficit Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Scheres, Anouk; Oosterlaan, Jaap; Sergeant, Joseph A.

    2006-01-01

    This study aimed at investigating whether one of the key deficits in Attention Deficit Hyperactivity Disorder (ADHD), slow response inhibition, predicted the response to methylphenidate (MPH) treatment. In order to address this issue, we used Stop Signal Reaction Times (SSRTs) measured at baseline in 20 medication-naive boys with ADHD as…

  2. Threat Related Selective Attention Predicts Treatment Success in Childhood Anxiety Disorders

    ERIC Educational Resources Information Center

    Legerstee, Jeroen S.; Tulen, Joke H. M.; Kallen, Victor L.; Dieleman, Gwen C.; Treffers, Philip D. A.; Verhulst, Frank C.; Utens, Elisabeth M. W. J.

    2009-01-01

    Threat-related selective attention was found to predict the success of the treatment of childhood anxiety disorders through administering a pictorial dot-probe task to 131 children with anxiety disorders prior to cognitive behavioral therapy. The diagnostic status of the subjects was evaluated with a semistructured clinical interview at both pre-…

  3. Predicting Attention-Deficit/Hyperactivity Disorder and Oppositional Defiant Disorder from Preschool Diagnostic Assessments

    ERIC Educational Resources Information Center

    Harvey, Elizabeth A.; Youngwirth, Sara D.; Thakar, Dhara A.; Errazuriz, Paula A.

    2009-01-01

    The present study examined the power of measures of early preschool behavior to predict later diagnoses of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD)/conduct disorder (CD). Participants were 168 children with behavior problems at age 3 who underwent a multimethod assessment of ADHD and ODD symptoms and…

  4. Metacognition of multitasking: How well do we predict the costs of divided attention?

    PubMed

    Finley, Jason R; Benjamin, Aaron S; McCarley, Jason S

    2014-06-01

    Risky multitasking, such as texting while driving, may occur because people misestimate the costs of divided attention. In two experiments, participants performed a computerized visual-manual tracking task in which they attempted to keep a mouse cursor within a small target that moved erratically around a circular track. They then separately performed an auditory n-back task. After practicing both tasks separately, participants received feedback on their single-task tracking performance and predicted their dual-task tracking performance before finally performing the 2 tasks simultaneously. Most participants correctly predicted reductions in tracking performance under dual-task conditions, with a majority overestimating the costs of dual-tasking. However, the between-subjects correlation between predicted and actual performance decrements was near 0. This combination of results suggests that people do anticipate costs of multitasking, but have little metacognitive insight on the extent to which they are personally vulnerable to the risks of divided attention, relative to other people.

  5. Effects of Spectral Degradation on Attentional Modulation of Cortical Auditory Responses to Continuous Speech.

    PubMed

    Kong, Ying-Yee; Somarowthu, Ala; Ding, Nai

    2015-12-01

    This study investigates the effect of spectral degradation on cortical speech encoding in complex auditory scenes. Young normal-hearing listeners were simultaneously presented with two speech streams and were instructed to attend to only one of them. The speech mixtures were subjected to noise-channel vocoding to preserve the temporal envelope and degrade the spectral information of speech. Each subject was tested with five spectral resolution conditions (unprocessed speech, 64-, 32-, 16-, and 8-channel vocoder conditions) and two target-to-masker ratio (TMR) conditions (3 and 0 dB). Ongoing electroencephalographic (EEG) responses and speech comprehension were measured in each spectral and TMR condition for each subject. Neural tracking of each speech stream was characterized by cross-correlating the EEG responses with the envelope of each of the simultaneous speech streams at different time lags. Results showed that spectral degradation and TMR both significantly influenced how top-down attention modulated the EEG responses to the attended and unattended speech. That is, the EEG responses to the attended and unattended speech streams differed more for the higher (unprocessed, 64 ch, and 32 ch) than the lower (16 and 8 ch) spectral resolution conditions, as well as for the higher (3 dB) than the lower TMR (0 dB) condition. The magnitude of differential neural modulation responses to the attended and unattended speech streams significantly correlated with speech comprehension scores. These results suggest that severe spectral degradation and low TMR hinder speech stream segregation, making it difficult to employ top-down attention to differentially process different speech streams. PMID:26362546

  6. Effects of Spectral Degradation on Attentional Modulation of Cortical Auditory Responses to Continuous Speech.

    PubMed

    Kong, Ying-Yee; Somarowthu, Ala; Ding, Nai

    2015-12-01

    This study investigates the effect of spectral degradation on cortical speech encoding in complex auditory scenes. Young normal-hearing listeners were simultaneously presented with two speech streams and were instructed to attend to only one of them. The speech mixtures were subjected to noise-channel vocoding to preserve the temporal envelope and degrade the spectral information of speech. Each subject was tested with five spectral resolution conditions (unprocessed speech, 64-, 32-, 16-, and 8-channel vocoder conditions) and two target-to-masker ratio (TMR) conditions (3 and 0 dB). Ongoing electroencephalographic (EEG) responses and speech comprehension were measured in each spectral and TMR condition for each subject. Neural tracking of each speech stream was characterized by cross-correlating the EEG responses with the envelope of each of the simultaneous speech streams at different time lags. Results showed that spectral degradation and TMR both significantly influenced how top-down attention modulated the EEG responses to the attended and unattended speech. That is, the EEG responses to the attended and unattended speech streams differed more for the higher (unprocessed, 64 ch, and 32 ch) than the lower (16 and 8 ch) spectral resolution conditions, as well as for the higher (3 dB) than the lower TMR (0 dB) condition. The magnitude of differential neural modulation responses to the attended and unattended speech streams significantly correlated with speech comprehension scores. These results suggest that severe spectral degradation and low TMR hinder speech stream segregation, making it difficult to employ top-down attention to differentially process different speech streams.

  7. A biased activation theory of the cognitive and attentional modulation of emotion.

    PubMed

    Rolls, Edmund T

    2013-01-01

    Cognition can influence emotion by biasing neural activity in the first cortical region in which the reward value and subjective pleasantness of stimuli is made explicit in the representation, the orbitofrontal cortex (OFC). The same effect occurs in a second cortical tier for emotion, the anterior cingulate cortex (ACC). Similar effects are found for selective attention, to for example the pleasantness vs. the intensity of stimuli, which modulates representations of reward value and affect in the orbitofrontal and anterior cingulate cortices. The mechanisms for the effects of cognition and attention on emotion are top-down biased competition and top-down biased activation. Affective and mood states can in turn influence memory and perception, by backprojected biasing influences. Emotion-related decision systems operate to choose between gene-specified rewards such as taste, touch, and beauty. Reasoning processes capable of planning ahead with multiple steps held in working memory in the explicit system can allow the gene-specified rewards not to be selected, or to be deferred. The stochastic, noisy, dynamics of decision-making systems in the brain may influence whether decisions are made by the selfish-gene-specified reward emotion system, or by the cognitive reasoning system that explicitly calculates reward values that are in the interests of the individual, the phenotype.

  8. Attention Modulates Neural Responses to Unpredictable Emotional Faces in Dorsolateral Prefrontal Cortex

    PubMed Central

    Ran, Guangming; Chen, Xu; Zhang, Qi; Ma, Yuanxiao; Zhang, Xing

    2016-01-01

    Unpredictability about upcoming emotional events disrupts our ability to prepare for them and ultimately results in anxiety. Here, we investigated how attention modulates the neural responses to unpredictable emotional events. Brain activity was recorded using functional magnetic resonance imaging (fMRI) while participants performed a variation of the emotional task. Behaviorally, we reported a fear-unpredictable effect and a happy-unpredictable effect. The fMRI results showed increased activity in the right dorsolateral prefrontal cortex (dlPFC) for unpredictable fear faces (Experiment 1) and decreased activity in the left dlPFC for unpredictable happy faces (Experiment 2) when these faces were unattended, probably reflecting that unpredictability amplifies the negative impact of fear faces and reduces the positive impact of happy faces. More importantly, it was found that the right dlPFC activity to unpredictable fear faces was diminished (Experiment 1) and the left dlPFC activity to unpredictable happy faces was enhanced (Experiment 2) when these faces were attended. These results suggest that attention may contribute to reducing the unpredictability about future emotional events. PMID:27445769

  9. Temporal dynamics underlying the modulation of social status on social attention.

    PubMed

    Dalmaso, Mario; Galfano, Giovanni; Coricelli, Carol; Castelli, Luigi

    2014-01-01

    Fixating someone suddenly moving the eyes is known to trigger a corresponding shift of attention in the observer. This phenomenon, known as gaze-cueing effect, can be modulated as a function of the social status of the individual depicted in the cueing face. Here, in two experiments, we investigated the temporal dynamics underlying this modulation. To this end, a gaze-cueing paradigm was implemented in which centrally-placed faces depicting high- and low-status individuals suddenly shifted the eyes towards a location either spatially congruent or incongruent with that occupied by a subsequent target stimulus. Social status was manipulated by presenting fictive Curriculum Vitae before the experimental phase. In Experiment 1, in which two temporal intervals (50 ms vs. 900 ms) occurred between the direct-gaze face and the averted-gaze face onsets, a stronger gaze-cueing effect in response to high-status faces than low-status faces was observed, irrespective of the time participants were allowed for extracting social information. In Experiment 2, in which two temporal intervals (200 ms vs. 1000 ms) occurred between the averted-gaze face and target onset, a stronger gaze cueing for high-status faces was observed at the shorter interval only. Taken together, these results suggest that information regarding social status is extracted from faces rapidly (Experiment 1), and that the tendency to selectively attend to the locations gazed by high-status individuals may decay with time (Experiment 2).

  10. Structural Organization of the Corpus Callosum Predicts Attentional Shifts after Continuous Theta Burst Stimulation

    PubMed Central

    Humphreys, Glyn W.; Sotiropoulos, Stamatios N.; Kennard, Christopher; Cazzoli, Dario

    2015-01-01

    Repetitive transcranial magnetic stimulation (rTMS) applied over the right posterior parietal cortex (PPC) in healthy participants has been shown to trigger a significant rightward shift in the spatial allocation of visual attention, temporarily mimicking spatial deficits observed in neglect. In contrast, rTMS applied over the left PPC triggers a weaker or null attentional shift. However, large interindividual differences in responses to rTMS have been reported. Studies measuring changes in brain activation suggest that the effects of rTMS may depend on both interhemispheric and intrahemispheric interactions between cortical loci controlling visual attention. Here, we investigated whether variability in the structural organization of human white matter pathways subserving visual attention, as assessed by diffusion magnetic resonance imaging and tractography, could explain interindividual differences in the effects of rTMS. Most participants showed a rightward shift in the allocation of spatial attention after rTMS over the right intraparietal sulcus (IPS), but the size of this effect varied largely across participants. Conversely, rTMS over the left IPS resulted in strikingly opposed individual responses, with some participants responding with rightward and some with leftward attentional shifts. We demonstrate that microstructural and macrostructural variability within the corpus callosum, consistent with differential effects on cross-hemispheric interactions, predicts both the extent and the direction of the response to rTMS. Together, our findings suggest that the corpus callosum may have a dual inhibitory and excitatory function in maintaining the interhemispheric dynamics that underlie the allocation of spatial attention. SIGNIFICANCE STATEMENT The posterior parietal cortex (PPC) controls allocation of attention across left versus right visual fields. Damage to this area results in neglect, characterized by a lack of spatial awareness of the side of space

  11. Theoretical Approach to Predict the Performance of Thermoelectric Generator Modules

    NASA Astrophysics Data System (ADS)

    Elarusi, Abdulmunaem H.; Fagehi, Hassan; Lee, Hosung; Attar, Alaa

    2016-10-01

    The aim of this work was to examine the validity of the thermoelectric modules' performance predicted by formulating the effective thermoelectric material properties. The three maximum parameters (output power, current, and efficiency) are defined in terms of the average temperature of the thermoelectric generator (TEG). These three maximum parameters, which are either taken from commercial TEG modules or measurements for particular operating conditions, are used to define the effective material properties (Seebeck coefficient, thermal conductivity, and electrical resistivity). The commercial performance curves provided by the manufacturer were compared with the results obtained here by the effective material properties with the simple standard thermoelectric equations. It has been found that this technique predicts the performance of four commercial thermoelectric modules with fair to good accuracy. The characteristics of the TEGs were represented using the normalized charts constructed by formulating the parameters as a fraction of over the maximum parameters. The normalized charts would be universal for any given TEG module once the thermoelectric material is known.

  12. Attention modulates specificity effects in spoken word recognition: Challenges to the time-course hypothesis

    PubMed Central

    Theodore, Rachel M.; Blumstein, Sheila E.; Luthra, Sahil

    2015-01-01

    Findings in the domain of spoken word recognition indicate that lexical representations contain both abstract and episodic information. It has been proposed that processing time determines when each source of information is recruited, with increased processing time required to access lower-frequency episodic instantiations. The time-course hypothesis of specificity effects thus identifies a strong role for retrieval mechanisms mediating the use of abstract versus episodic information. Here we conducted three recognition memory experiments to examine whether findings previously attributed to retrieval mechanisms might reflect attention during encoding. Results from Experiment 1 showed that talker-specificity effects emerged when subjects attended to individual speakers during encoding, but not when they attended to lexical characteristics during encoding, even though processing time at retrieval was equivalent. Results from Experiment 2 showed that talker-specificity effects emerged when listeners attended to talker gender but not when they attended to syntactic characteristics, even though processing time at retrieval was significantly longer in the latter condition. Results from Experiment 3 showed no talker-specificity effects when attending to lexical characteristics even when processing at retrieval was slowed by the addition of background noise. Collectively, these results suggest that when processing time during retrieval is decoupled from encoding factors, it fails to predict the emergence of talker-specificity effects. Rather, attention during encoding appears to be the putative variable. PMID:25824889

  13. Modulation of trigeminal reflex excitability in migraine: effects of attention and habituation on the blink reflex.

    PubMed

    de Tommaso, Marina; Murasecco, Donatella; Libro, Giuseppe; Guido, Marco; Sciruicchio, Vittorio; Specchio, Luigi Maria; Gallai, Virgilio; Puca, Francomichele

    2002-06-01

    The modulation of trigeminal reflex excitability in migraine patients was evaluated during the asymptomatic phase by studying the effects of attention, habituation and preconditioning stimulus on the R2 and R3 components of the blink reflex (BR). Fifty patients suffering from migraine without aura, 20 affected by migraine with aura and 35 sex- and age-matched controls were selected. In subgroups of migraine with-aura and without-aura patients, and normal controls, the blink reflex was elicited during different cognitive situations: (a) spontaneous mental activity; (b) stimulus anticipation; (c) recognition of target numbers. In the remaining subjects, R2 and R3 habituation was evaluated by repetitive stimulation at 1, 5, 10, 15, 20, 25 and 30 s intervals. The R2 and R3 recovery curves were also computed. A reduced R3 threshold with a normal pain threshold was found in migraine with-aura and without-aura patients; the R3 component was not significantly correlated with the pain thresholds in patients and controls. The R2 and R3 components were less influenced by the warning of the stimulus in migraine without-aura and migraine with-aura patients, in comparison with the control group. A slight increase of both R2 and R3 recovery after preconditioning stimulus was also observed in migraine patients, probably caused by a phenomenon of trigeminal hyperexcitability persisting after the last attack. The abnormal BR modulation by alerting expresses in migraine a dysfunction of adaptation capacity to environmental conditions, probably predisposing to migraine. PMID:12031298

  14. Modulation of trigeminal reflex excitability in migraine: effects of attention and habituation on the blink reflex.

    PubMed

    de Tommaso, Marina; Murasecco, Donatella; Libro, Giuseppe; Guido, Marco; Sciruicchio, Vittorio; Specchio, Luigi Maria; Gallai, Virgilio; Puca, Francomichele

    2002-06-01

    The modulation of trigeminal reflex excitability in migraine patients was evaluated during the asymptomatic phase by studying the effects of attention, habituation and preconditioning stimulus on the R2 and R3 components of the blink reflex (BR). Fifty patients suffering from migraine without aura, 20 affected by migraine with aura and 35 sex- and age-matched controls were selected. In subgroups of migraine with-aura and without-aura patients, and normal controls, the blink reflex was elicited during different cognitive situations: (a) spontaneous mental activity; (b) stimulus anticipation; (c) recognition of target numbers. In the remaining subjects, R2 and R3 habituation was evaluated by repetitive stimulation at 1, 5, 10, 15, 20, 25 and 30 s intervals. The R2 and R3 recovery curves were also computed. A reduced R3 threshold with a normal pain threshold was found in migraine with-aura and without-aura patients; the R3 component was not significantly correlated with the pain thresholds in patients and controls. The R2 and R3 components were less influenced by the warning of the stimulus in migraine without-aura and migraine with-aura patients, in comparison with the control group. A slight increase of both R2 and R3 recovery after preconditioning stimulus was also observed in migraine patients, probably caused by a phenomenon of trigeminal hyperexcitability persisting after the last attack. The abnormal BR modulation by alerting expresses in migraine a dysfunction of adaptation capacity to environmental conditions, probably predisposing to migraine.

  15. Biased ART: a neural architecture that shifts attention toward previously disregarded features following an incorrect prediction.

    PubMed

    Carpenter, Gail A; Gaddam, Sai Chaitanya

    2010-04-01

    Memories in Adaptive Resonance Theory (ART) networks are based on matched patterns that focus attention on those portions of bottom-up inputs that match active top-down expectations. While this learning strategy has proved successful for both brain models and applications, computational examples show that attention to early critical features may later distort memory representations during online fast learning. For supervised learning, biased ARTMAP (bARTMAP) solves the problem of over-emphasis on early critical features by directing attention away from previously attended features after the system makes a predictive error. Small-scale, hand-computed analog and binary examples illustrate key model dynamics. Two-dimensional simulation examples demonstrate the evolution of bARTMAP memories as they are learned online. Benchmark simulations show that featural biasing also improves performance on large-scale examples. One example, which predicts movie genres and is based, in part, on the Netflix Prize database, was developed for this project. Both first principles and consistent performance improvements on all simulation studies suggest that featural biasing should be incorporated by default in all ARTMAP systems. Benchmark datasets and bARTMAP code are available from the CNS Technology Lab Website: http://techlab.bu.edu/bART/.

  16. Prepulse inhibition of the startle reflex and its attentional modulation in the human S-ketamine and N,N-dimethyltryptamine (DMT) models of psychosis.

    PubMed

    Heekeren, K; Neukirch, A; Daumann, J; Stoll, M; Obradovic, M; Kovar, K-A; Geyer, M A; Gouzoulis-Mayfrank, E

    2007-05-01

    Patients with schizophrenia exhibit diminished prepulse inhibition (PPI) of the acoustic startle reflex and deficits in the attentional modulation of PPI. Pharmacological challenges with hallucinogens are used as models for psychosis in both humans and animals. Remarkably, in contrast to the findings in schizophrenic patients and in animal hallucinogen models of psychosis, previous studies with healthy volunteers demonstrated increased levels of PPI after administration of low to moderate doses of either the antiglutamatergic hallucinogen ketamine or the serotonergic hallucinogen psilocybin. The aim of the present study was to investigate the influence of moderate and high doses of the serotonergic hallucinogen N,N-dimethyltryptamine (DMT) and the N-methyl-D-aspartate antagonist S-ketamine on PPI and its attentional modulation in humans. Fifteen healthy volunteers were included in a double-blind cross-over study with two doses of DMT and S-ketamine. Effects on PPI and its attentional modulation were investigated. Nine subjects completed both experimental days with the two doses of both drugs. S-ketamine increased PPI in both dosages, whereas DMT had no significant effects on PPI. S-ketamine decreased and DMT tended to decrease startle magnitude. There were no significant effects of either drug on the attentional modulation of PPI. In human experimental hallucinogen psychoses, and even with high, clearly psychotogenic doses of DMT or S-ketamine, healthy subjects failed to exhibit the predicted attenuation of PPI. In contrast, PPI was augmented and the startle magnitude was decreased after S-ketamine. These data point to important differences between human hallucinogen models and both animal hallucinogen models of psychosis and naturally occurring schizophrenia.

  17. Can attention deficits predict a genotype? Isolate attention difficulties in a boy with klinefelter syndrome effectively treated with methylphenidate.

    PubMed

    Gagliano, Antonella; Germanò, Eva; Benedetto, Loredana; Masi, Gabriele

    2014-01-01

    This paper describes a 17-year-old boy who was diagnosed with Klinefelter syndrome (KS) (XXY) at the age of 16 years. Although cognitive level was absolutely normal, he showed attentional difficulties that negatively affected school adjustment. He was successfully treated with methylphenidate. A significant improvement was observed in the ADHD Rating Scale IV and in the inattention subscale score of the Conners Scales. The CGI-S score improved from 3 to 1, and the CGI-I score at the end point was 1 (very much improved). Also attention measures, particularly forward and backward digit span, improved with MPH treatment. Given the widely variable and often aspecific features, KS may run undiagnosed in a large majority of affected patients. A close attention to the cognitive phenotype may favour a correct diagnosis, and a timely treatment.

  18. Belief about nicotine selectively modulates value and reward prediction error signals in smokers

    PubMed Central

    Gu, Xiaosi; Lohrenz, Terry; Salas, Ramiro; Baldwin, Philip R.; Soltani, Alireza; Kirk, Ulrich; Cinciripini, Paul M.; Montague, P. Read

    2015-01-01

    Little is known about how prior beliefs impact biophysically described processes in the presence of neuroactive drugs, which presents a profound challenge to the understanding of the mechanisms and treatments of addiction. We engineered smokers’ prior beliefs about the presence of nicotine in a cigarette smoked before a functional magnetic resonance imaging session where subjects carried out a sequential choice task. Using a model-based approach, we show that smokers’ beliefs about nicotine specifically modulated learning signals (value and reward prediction error) defined by a computational model of mesolimbic dopamine systems. Belief of “no nicotine in cigarette” (compared with “nicotine in cigarette”) strongly diminished neural responses in the striatum to value and reward prediction errors and reduced the impact of both on smokers’ choices. These effects of belief could not be explained by global changes in visual attention and were specific to value and reward prediction errors. Thus, by modulating the expression of computationally explicit signals important for valuation and choice, beliefs can override the physical presence of a potent neuroactive compound like nicotine. These selective effects of belief demonstrate that belief can modulate model-based parameters important for learning. The implications of these findings may be far ranging because belief-dependent effects on learning signals could impact a host of other behaviors in addiction as well as in other mental health problems. PMID:25605923

  19. Belief about nicotine selectively modulates value and reward prediction error signals in smokers.

    PubMed

    Gu, Xiaosi; Lohrenz, Terry; Salas, Ramiro; Baldwin, Philip R; Soltani, Alireza; Kirk, Ulrich; Cinciripini, Paul M; Montague, P Read

    2015-02-24

    Little is known about how prior beliefs impact biophysically described processes in the presence of neuroactive drugs, which presents a profound challenge to the understanding of the mechanisms and treatments of addiction. We engineered smokers' prior beliefs about the presence of nicotine in a cigarette smoked before a functional magnetic resonance imaging session where subjects carried out a sequential choice task. Using a model-based approach, we show that smokers' beliefs about nicotine specifically modulated learning signals (value and reward prediction error) defined by a computational model of mesolimbic dopamine systems. Belief of "no nicotine in cigarette" (compared with "nicotine in cigarette") strongly diminished neural responses in the striatum to value and reward prediction errors and reduced the impact of both on smokers' choices. These effects of belief could not be explained by global changes in visual attention and were specific to value and reward prediction errors. Thus, by modulating the expression of computationally explicit signals important for valuation and choice, beliefs can override the physical presence of a potent neuroactive compound like nicotine. These selective effects of belief demonstrate that belief can modulate model-based parameters important for learning. The implications of these findings may be far ranging because belief-dependent effects on learning signals could impact a host of other behaviors in addiction as well as in other mental health problems.

  20. Temporal prediction errors modulate task-switching performance.

    PubMed

    Limongi, Roberto; Silva, Angélica M; Góngora-Costa, Begoña

    2015-01-01

    We have previously shown that temporal prediction errors (PEs, the differences between the expected and the actual stimulus' onset times) modulate the effective connectivity between the anterior cingulate cortex and the right anterior insular cortex (rAI), causing the activity of the rAI to decrease. The activity of the rAI is associated with efficient performance under uncertainty (e.g., changing a prepared behavior when a change demand is not expected), which leads to hypothesize that temporal PEs might disrupt behavior-change performance under uncertainty. This hypothesis has not been tested at a behavioral level. In this work, we evaluated this hypothesis within the context of task switching and concurrent temporal predictions. Our participants performed temporal predictions while observing one moving ball striking a stationary ball which bounced off with a variable temporal gap. Simultaneously, they performed a simple color comparison task. In some trials, a change signal made the participants change their behaviors. Performance accuracy decreased as a function of both the temporal PE and the delay. Explaining these results without appealing to ad hoc concepts such as "executive control" is a challenge for cognitive neuroscience. We provide a predictive coding explanation. We hypothesize that exteroceptive and proprioceptive minimization of PEs would converge in a fronto-basal ganglia network which would include the rAI. Both temporal gaps (or uncertainty) and temporal PEs would drive and modulate this network respectively. Whereas the temporal gaps would drive the activity of the rAI, the temporal PEs would modulate the endogenous excitatory connections of the fronto-striatal network. We conclude that in the context of perceptual uncertainty, the system is not able to minimize perceptual PE, causing the ongoing behavior to finalize and, in consequence, disrupting task switching. PMID:26379568

  1. Temporal prediction errors modulate task-switching performance

    PubMed Central

    Limongi, Roberto; Silva, Angélica M.; Góngora-Costa, Begoña

    2015-01-01

    We have previously shown that temporal prediction errors (PEs, the differences between the expected and the actual stimulus’ onset times) modulate the effective connectivity between the anterior cingulate cortex and the right anterior insular cortex (rAI), causing the activity of the rAI to decrease. The activity of the rAI is associated with efficient performance under uncertainty (e.g., changing a prepared behavior when a change demand is not expected), which leads to hypothesize that temporal PEs might disrupt behavior-change performance under uncertainty. This hypothesis has not been tested at a behavioral level. In this work, we evaluated this hypothesis within the context of task switching and concurrent temporal predictions. Our participants performed temporal predictions while observing one moving ball striking a stationary ball which bounced off with a variable temporal gap. Simultaneously, they performed a simple color comparison task. In some trials, a change signal made the participants change their behaviors. Performance accuracy decreased as a function of both the temporal PE and the delay. Explaining these results without appealing to ad hoc concepts such as “executive control” is a challenge for cognitive neuroscience. We provide a predictive coding explanation. We hypothesize that exteroceptive and proprioceptive minimization of PEs would converge in a fronto-basal ganglia network which would include the rAI. Both temporal gaps (or uncertainty) and temporal PEs would drive and modulate this network respectively. Whereas the temporal gaps would drive the activity of the rAI, the temporal PEs would modulate the endogenous excitatory connections of the fronto-striatal network. We conclude that in the context of perceptual uncertainty, the system is not able to minimize perceptual PE, causing the ongoing behavior to finalize and, in consequence, disrupting task switching. PMID:26379568

  2. Temporal prediction errors modulate task-switching performance.

    PubMed

    Limongi, Roberto; Silva, Angélica M; Góngora-Costa, Begoña

    2015-01-01

    We have previously shown that temporal prediction errors (PEs, the differences between the expected and the actual stimulus' onset times) modulate the effective connectivity between the anterior cingulate cortex and the right anterior insular cortex (rAI), causing the activity of the rAI to decrease. The activity of the rAI is associated with efficient performance under uncertainty (e.g., changing a prepared behavior when a change demand is not expected), which leads to hypothesize that temporal PEs might disrupt behavior-change performance under uncertainty. This hypothesis has not been tested at a behavioral level. In this work, we evaluated this hypothesis within the context of task switching and concurrent temporal predictions. Our participants performed temporal predictions while observing one moving ball striking a stationary ball which bounced off with a variable temporal gap. Simultaneously, they performed a simple color comparison task. In some trials, a change signal made the participants change their behaviors. Performance accuracy decreased as a function of both the temporal PE and the delay. Explaining these results without appealing to ad hoc concepts such as "executive control" is a challenge for cognitive neuroscience. We provide a predictive coding explanation. We hypothesize that exteroceptive and proprioceptive minimization of PEs would converge in a fronto-basal ganglia network which would include the rAI. Both temporal gaps (or uncertainty) and temporal PEs would drive and modulate this network respectively. Whereas the temporal gaps would drive the activity of the rAI, the temporal PEs would modulate the endogenous excitatory connections of the fronto-striatal network. We conclude that in the context of perceptual uncertainty, the system is not able to minimize perceptual PE, causing the ongoing behavior to finalize and, in consequence, disrupting task switching.

  3. Metacognition of multitasking: How well do we predict the costs of divided attention?

    PubMed

    Finley, Jason R; Benjamin, Aaron S; McCarley, Jason S

    2014-06-01

    Risky multitasking, such as texting while driving, may occur because people misestimate the costs of divided attention. In two experiments, participants performed a computerized visual-manual tracking task in which they attempted to keep a mouse cursor within a small target that moved erratically around a circular track. They then separately performed an auditory n-back task. After practicing both tasks separately, participants received feedback on their single-task tracking performance and predicted their dual-task tracking performance before finally performing the 2 tasks simultaneously. Most participants correctly predicted reductions in tracking performance under dual-task conditions, with a majority overestimating the costs of dual-tasking. However, the between-subjects correlation between predicted and actual performance decrements was near 0. This combination of results suggests that people do anticipate costs of multitasking, but have little metacognitive insight on the extent to which they are personally vulnerable to the risks of divided attention, relative to other people. PMID:24490818

  4. Building gene expression signatures indicative of transcription factor activation to predict AOP modulation

    EPA Science Inventory

    Building gene expression signatures indicative of transcription factor activation to predict AOP modulation Adverse outcome pathways (AOPs) are a framework for predicting quantitative relationships between molecular initiatin...

  5. Bias corrected double judgment accuracy during spatial attention cueing: unmasked stimuli with non-predictive and semi-predictive cues.

    PubMed

    Pack, Weston; Klein, Stanley A; Carney, Thom

    2014-12-01

    The present experiments indicate that in a 7-AFC double judgment accuracy task with unmasked stimuli, cue location response bias can be quantified and removed, revealing unbiased improvements in response accuracy for valid cues compared to invalid cues. By testing for cueing effects over a range of contrast levels with unmasked stimuli, changes in the psychometric function were examined and provide insight into the mechanisms of involuntary attention which might account for the observed cueing effects. Cue validity was varied between two separate experiments showing that non-predictive (14.3%) and moderately-predictive cues (50%) equally facilitate stimulus identification and localization during transient involuntary attention capture. Observers had improved accuracy at identifying both the location and the feature identity of target letters throughout a range of contrast levels, without any dependence on backward masking. There was a leftward shift of the psychometric function threshold with valid cued data and no slope reduction suggesting that any additive hypothesis based on spatial uncertainty reduction or perceptual enhancement is not a sufficient explanation for the observed cueing effects. The interdependence of the perceptual processes of stimulus discrimination and localization were also investigated by analyzing response contingencies, showing that observers were equally skilled at making identification and localization accuracy judgments with unmasked stimuli.

  6. Predicting Fault-Prone Modules: A Comparative Study

    NASA Astrophysics Data System (ADS)

    Jia, Hao; Shu, Fengdi; Yang, Ye; Wang, Qing

    Offshore and outsourced software development is a rapidly increasing trend in global software business environment. Predicting fault-prone modules in outsourced software product may allow both parties to establish mutually satisfactory, cost-effective testing strategies and product acceptance criteria, especially in iterative transitions. In this paper, based on industrial software releases data, we conduct an empirical study to compare ten classifiers over eight sets of code attributes, and provide recommendations to aid both the client and vendor to assess the products’ quality through defect prediction. Overall, a generally high accuracy is observed, which confirms the usefulness of the metric-based classification. Furthermore, two classification techniques, Random Forest and Bayesian Belief Network, outperform the others in terms of predictive accuracy; in more detail, the former is the most cost-effective and the latter is of the lowest fault-prone module escaping rate. Our study also concludes that code metrics including size, traditional complexity, and object-oriented complexity perform fairly well.

  7. Threat/reward-sensitivity and hypomanic-personality modulate cognitive-control and attentional neural processes to emotional stimuli.

    PubMed

    Pornpattananangkul, Narun; Hu, Xiaoqing; Nusslock, Robin

    2015-11-01

    Temperamental-traits (e.g. threat/reward-sensitivity) are found to modulate cognitive-control and attentional-processes. Yet, it is unclear exactly how these traits interact with emotional-stimuli in the modulation of cognitive-control, as reflected by the N2 event-related potential (ERP), and attentional-processes, as reflected by the P2 and P3 ERPs. Here in an ERP emotional-Go/NoGo task, 36 participants were instructed to inhibit their response to Fearful- and Happy-faces. Individual-differences in threat-sensitivity, reward-sensitivity and hypomanic-personality were assessed through self-report. Hypomanic-personality was assessed, given its relationship with reward-sensitivity and relevance to mood-disorder symptoms. Concerning cognitive-control, individuals with elevated threat-sensitivity displayed more-negative N2s to Happy-NoGo (relative to Fearful-NoGo) faces, whereas both individuals with elevated reward-sensitivity and hypomanic-personality displayed more-negative N2s to Fearful-NoGo (relative to Happy-NoGo) faces. Accordingly, when cognitive-control is required (during Go/NoGo), a mismatch between one's temperament and the valence of the NoGo-stimulus elevates detection of the need for cognitive-control. Conversely, the modulation of attentional-processing was specific to threat-sensitivity, as there was no relationship between either reward-sensitivity or hypomanic-personality and attentional-processing. Elevated threat-sensitivity was associated with enhanced early (P2s) and later (P3s) attentional-processing to Fearful-NoGo (relative to Happy-NoGo) faces. These latter findings support the negative attentional-bias model relating elevated threat-sensitivity with attentional-biases toward negative-stimuli and away from positive-stimuli.

  8. Attentional gain and processing capacity limits predict the propensity to neglect unexpected visual stimuli.

    PubMed

    Papera, Massimiliano; Richards, Anne

    2016-05-01

    Exogenous allocation of attentional resources allows the visual system to encode and maintain representations of stimuli in visual working memory (VWM). However, limits in the processing capacity to allocate resources can prevent unexpected visual stimuli from gaining access to VWM and thereby to consciousness. Using a novel approach to create unbiased stimuli of increasing saliency, we investigated visual processing during a visual search task in individuals who show a high or low propensity to neglect unexpected stimuli. When propensity to inattention is high, ERP recordings show a diminished amplification concomitantly with a decrease in theta band power during the N1 latency, followed by a poor target enhancement during the N2 latency. Furthermore, a later modulation in the P3 latency was also found in individuals showing propensity to visual neglect, suggesting that more effort is required for conscious maintenance of visual information in VWM. Effects during early stages of processing (N80 and P1) were also observed suggesting that sensitivity to contrasts and medium-to-high spatial frequencies may be modulated by low-level saliency (albeit no statistical group differences were found). In accordance with the Global Workplace Model, our data indicate that a lack of resources in low-level processors and visual attention may be responsible for the failure to "ignite" a state of high-level activity spread across several brain areas that is necessary for stimuli to access awareness. These findings may aid in the development of diagnostic tests and intervention to detect/reduce inattention propensity to visual neglect of unexpected stimuli. PMID:26849023

  9. Attentional gain and processing capacity limits predict the propensity to neglect unexpected visual stimuli.

    PubMed

    Papera, Massimiliano; Richards, Anne

    2016-05-01

    Exogenous allocation of attentional resources allows the visual system to encode and maintain representations of stimuli in visual working memory (VWM). However, limits in the processing capacity to allocate resources can prevent unexpected visual stimuli from gaining access to VWM and thereby to consciousness. Using a novel approach to create unbiased stimuli of increasing saliency, we investigated visual processing during a visual search task in individuals who show a high or low propensity to neglect unexpected stimuli. When propensity to inattention is high, ERP recordings show a diminished amplification concomitantly with a decrease in theta band power during the N1 latency, followed by a poor target enhancement during the N2 latency. Furthermore, a later modulation in the P3 latency was also found in individuals showing propensity to visual neglect, suggesting that more effort is required for conscious maintenance of visual information in VWM. Effects during early stages of processing (N80 and P1) were also observed suggesting that sensitivity to contrasts and medium-to-high spatial frequencies may be modulated by low-level saliency (albeit no statistical group differences were found). In accordance with the Global Workplace Model, our data indicate that a lack of resources in low-level processors and visual attention may be responsible for the failure to "ignite" a state of high-level activity spread across several brain areas that is necessary for stimuli to access awareness. These findings may aid in the development of diagnostic tests and intervention to detect/reduce inattention propensity to visual neglect of unexpected stimuli.

  10. Low Fidelity Imitation of Atypical Biological Kinematics in Autism Spectrum Disorders Is Modulated by Self-Generated Selective Attention.

    PubMed

    Hayes, Spencer J; Andrew, Matthew; Elliott, Digby; Gowen, Emma; Bennett, Simon J

    2016-02-01

    We examined whether adults with autism had difficulty imitating atypical biological kinematics. To reduce the impact that higher-order processes have on imitation we used a non-human agent model to control social attention, and removed end-state target goals in half of the trials to minimise goal-directed attention. Findings showed that only neurotypical adults imitated atypical biological kinematics. Adults with autism did, however, become significantly more accurate at imitating movement time. This confirmed they engaged in the task, and that sensorimotor adaptation was self-regulated. The attentional bias to movement time suggests the attenuation in imitating kinematics might be a compensatory strategy due to deficits in lower-level visuomotor processes associated with self-other mapping, or selective attention modulated the processes that represent biological kinematics.

  11. Attentional modulation of visual-evoked potentials by threat: investigating the effect of evolutionary relevance.

    PubMed

    Brown, Christopher; El-Deredy, Wael; Blanchette, Isabelle

    2010-12-01

    In dot-probe tasks, threatening cues facilitate attention to targets and enhance the amplitude of the target P1 peak of the visual-evoked potential. While theories have suggested that evolutionarily relevant threats should obtain preferential neural processing, this has not been examined empirically. In this study we examined the effects of evolutionarily relevant (e.g. spiders and snakes) and irrelevant (e.g. knifes and syringes) threatening cues. Non-predictive threatening cues (in left or right visual field) were paired with non-threatening cues and were followed by neutral targets in the same or opposite location. The amplitude of the target P1 was increased in contralateral electrodes when the target followed in the same location as the threatening cues. This effect did not interact with evolutionary relevance. Both evolutionary relevant and evolutionary irrelevant threats led to increased P1 amplitude, although the effect was stronger for modern threats. We conclude that the threat-superiority effect is robust and largely independent of the type of threatening stimulus.

  12. Demand and Modality of Directed Attention Modulate “Pre-attentive” Sensory Processes in Schizophrenia Patients and Nonpsychiatric Controls

    PubMed Central

    Rissling, Anthony J.; Park, Sung-Hyouk; Young, Jared W.; Rissling, Michelle B.; Sugar, Catherine A.; Sprock, Joyce; Mathias, Daniel J.; Pela, Marlena; Sharp, Richard F.; Braff, David L.; Light, Gregory A.

    2013-01-01

    Background Mismatch negativity (MNN) and P3a are event related potential (ERP) measures of early sensory information processing. These components are usually conceptualized as being “pre-attentive” and therefore immune to changes with variations in attentional functioning. This study aimed to determine whether manipulations of attention influence the amplitudes and latencies of MMN and P3a and, if so, the extent to which these early sensory processes govern concurrent behavioral vigilance performance in schizophrenia patients and normal subjects. Methods Schizophrenia patients (SZ; n=20) and Nonpsychiatric Control Subjects (NCS; n=20) underwent auditory ERP testing to assess MMN and P3a across 4 EEG recording sessions in which attentional demand (low vs. high) and sensory modality of directed attention (visual vs. auditory) were experimentally varied. Results Across conditions, SZ patients exhibited deficits in MMN and P3a amplitudes. Significant amplitude and latency modulation were observed in both SZ and NCS but there were no group-by- condition interactions. The amount of MMN amplitude attenuation from low- to-high-demand tasks was significantly associated with increased vigilance performance in both SZ and NCS groups (r=-0.67 and r=-0.60). Conclusions Attentional demand and modality of directed attention significantly influence the amplitude and latencies of “pre-attentive” ERP components in both SZ and NCS. Deficits in MMN and P3a were not “normalized” when attention was directed to the auditory stimuli in schizophrenia patients. The adaptive modulation of early sensory information processing appears to govern concurrent attentional task performance. MMN and P3a may serve as a gateway to some higher order cognitive operations necessary for psychosocial functioning. PMID:23490760

  13. Predictive coding in autism spectrum disorder and attention deficit hyperactivity disorder.

    PubMed

    Gonzalez-Gadea, Maria Luz; Chennu, Srivas; Bekinschtein, Tristan A; Rattazzi, Alexia; Beraudi, Ana; Tripicchio, Paula; Moyano, Beatriz; Soffita, Yamila; Steinberg, Laura; Adolfi, Federico; Sigman, Mariano; Marino, Julian; Manes, Facundo; Ibanez, Agustin

    2015-11-01

    Predictive coding has been proposed as a framework to understand neural processes in neuropsychiatric disorders. We used this approach to describe mechanisms responsible for attentional abnormalities in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). We monitored brain dynamics of 59 children (8-15 yr old) who had ASD or ADHD or who were control participants via high-density electroencephalography. We performed analysis at the scalp and source-space levels while participants listened to standard and deviant tone sequences. Through task instructions, we manipulated top-down expectation by presenting expected and unexpected deviant sequences. Children with ASD showed reduced superior frontal cortex (FC) responses to unexpected events but increased dorsolateral prefrontal cortex (PFC) activation to expected events. In contrast, children with ADHD exhibited reduced cortical responses in superior FC to expected events but strong PFC activation to unexpected events. Moreover, neural abnormalities were associated with specific control mechanisms, namely, inhibitory control in ASD and set-shifting in ADHD. Based on the predictive coding account, top-down expectation abnormalities could be attributed to a disproportionate reliance (precision) allocated to prior beliefs in ASD and to sensory input in ADHD.

  14. Predictive coding in autism spectrum disorder and attention deficit hyperactivity disorder.

    PubMed

    Gonzalez-Gadea, Maria Luz; Chennu, Srivas; Bekinschtein, Tristan A; Rattazzi, Alexia; Beraudi, Ana; Tripicchio, Paula; Moyano, Beatriz; Soffita, Yamila; Steinberg, Laura; Adolfi, Federico; Sigman, Mariano; Marino, Julian; Manes, Facundo; Ibanez, Agustin

    2015-11-01

    Predictive coding has been proposed as a framework to understand neural processes in neuropsychiatric disorders. We used this approach to describe mechanisms responsible for attentional abnormalities in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). We monitored brain dynamics of 59 children (8-15 yr old) who had ASD or ADHD or who were control participants via high-density electroencephalography. We performed analysis at the scalp and source-space levels while participants listened to standard and deviant tone sequences. Through task instructions, we manipulated top-down expectation by presenting expected and unexpected deviant sequences. Children with ASD showed reduced superior frontal cortex (FC) responses to unexpected events but increased dorsolateral prefrontal cortex (PFC) activation to expected events. In contrast, children with ADHD exhibited reduced cortical responses in superior FC to expected events but strong PFC activation to unexpected events. Moreover, neural abnormalities were associated with specific control mechanisms, namely, inhibitory control in ASD and set-shifting in ADHD. Based on the predictive coding account, top-down expectation abnormalities could be attributed to a disproportionate reliance (precision) allocated to prior beliefs in ASD and to sensory input in ADHD. PMID:26311184

  15. Modulation of Auditory Spatial Attention by Angry Prosody: An fMRI Auditory Dot-Probe Study.

    PubMed

    Ceravolo, Leonardo; Frühholz, Sascha; Grandjean, Didier

    2016-01-01

    Emotional stimuli have been shown to modulate attentional orienting through signals sent by subcortical brain regions that modulate visual perception at early stages of processing. Fewer studies, however, have investigated a similar effect of emotional stimuli on attentional orienting in the auditory domain together with an investigation of brain regions underlying such attentional modulation, which is the general aim of the present study. Therefore, we used an original auditory dot-probe paradigm involving simultaneously presented neutral and angry non-speech vocal utterances lateralized to either the left or the right auditory space, immediately followed by a short and lateralized single sine wave tone presented in the same (valid trial) or in the opposite space as the preceding angry voice (invalid trial). Behavioral results showed an expected facilitation effect for target detection during valid trials while functional data showed greater activation in the middle and posterior superior temporal sulci (STS) and in the medial frontal cortex for valid vs. invalid trials. The use of reaction time facilitation [absolute value of the Z-score of valid-(invalid+neutral)] as a group covariate extended enhanced activity in the amygdalae, auditory thalamus, and visual cortex. Taken together, our results suggest the involvement of a large and distributed network of regions among which the STS, thalamus, and amygdala are crucial for the decoding of angry prosody, as well as for orienting and maintaining attention within an auditory space that was previously primed by a vocal emotional event.

  16. Effect of reduced attention on auditory amplitude-modulation following responses: a study with chirp-evoked potentials.

    PubMed

    Alegre, Manuel; Barbosa, Carla; Valencia, Miguel; Pérez-Alcázar, Marta; Iriarte, Jorge; Artieda, Julio

    2008-02-01

    The amplitude of the auditory amplitude-modulation following responses (AMFR) is variable, depending on the modulation rate. Although 40-Hz responses have higher amplitudes in adults, the AMFR in the 80- to 120-Hz range are less influenced by sleep and more consistent in children. The effect of attention on 40-Hz responses has been addressed in some studies; however, no study to our knowledge has investigated the effect of attention on other stimulation rates. Our aim was to test the effect of attention on the AMFR to different frequencies of stimulation, using a chirp-modulated tone as stimulus. We recorded chirp-evoked responses in 12 subjects while attending to the sound (first condition) and reading a novel (second condition), in a randomly determined sequence. The energy of the response and the intertrial coherence (ITC) were measured by means of time-frequency transforms. The frequency range of response was similar in both conditions. No significant differences were found in the ITC values in the 40-Hz and the 80- to 120-Hz ranges, nor in the energy of the 40-Hz response. The only statistically significant difference found was the lower energy of the response in the 80- to 120-Hz range in the reading condition. Our results suggest that attention may affect auditory steady-state clinical testing using amplitude values. Phase measures may be preferable in this context.

  17. Modulation of Auditory Spatial Attention by Angry Prosody: An fMRI Auditory Dot-Probe Study.

    PubMed

    Ceravolo, Leonardo; Frühholz, Sascha; Grandjean, Didier

    2016-01-01

    Emotional stimuli have been shown to modulate attentional orienting through signals sent by subcortical brain regions that modulate visual perception at early stages of processing. Fewer studies, however, have investigated a similar effect of emotional stimuli on attentional orienting in the auditory domain together with an investigation of brain regions underlying such attentional modulation, which is the general aim of the present study. Therefore, we used an original auditory dot-probe paradigm involving simultaneously presented neutral and angry non-speech vocal utterances lateralized to either the left or the right auditory space, immediately followed by a short and lateralized single sine wave tone presented in the same (valid trial) or in the opposite space as the preceding angry voice (invalid trial). Behavioral results showed an expected facilitation effect for target detection during valid trials while functional data showed greater activation in the middle and posterior superior temporal sulci (STS) and in the medial frontal cortex for valid vs. invalid trials. The use of reaction time facilitation [absolute value of the Z-score of valid-(invalid+neutral)] as a group covariate extended enhanced activity in the amygdalae, auditory thalamus, and visual cortex. Taken together, our results suggest the involvement of a large and distributed network of regions among which the STS, thalamus, and amygdala are crucial for the decoding of angry prosody, as well as for orienting and maintaining attention within an auditory space that was previously primed by a vocal emotional event. PMID:27242420

  18. Modulation of Auditory Spatial Attention by Angry Prosody: An fMRI Auditory Dot-Probe Study

    PubMed Central

    Ceravolo, Leonardo; Frühholz, Sascha; Grandjean, Didier

    2016-01-01

    Emotional stimuli have been shown to modulate attentional orienting through signals sent by subcortical brain regions that modulate visual perception at early stages of processing. Fewer studies, however, have investigated a similar effect of emotional stimuli on attentional orienting in the auditory domain together with an investigation of brain regions underlying such attentional modulation, which is the general aim of the present study. Therefore, we used an original auditory dot-probe paradigm involving simultaneously presented neutral and angry non-speech vocal utterances lateralized to either the left or the right auditory space, immediately followed by a short and lateralized single sine wave tone presented in the same (valid trial) or in the opposite space as the preceding angry voice (invalid trial). Behavioral results showed an expected facilitation effect for target detection during valid trials while functional data showed greater activation in the middle and posterior superior temporal sulci (STS) and in the medial frontal cortex for valid vs. invalid trials. The use of reaction time facilitation [absolute value of the Z-score of valid-(invalid+neutral)] as a group covariate extended enhanced activity in the amygdalae, auditory thalamus, and visual cortex. Taken together, our results suggest the involvement of a large and distributed network of regions among which the STS, thalamus, and amygdala are crucial for the decoding of angry prosody, as well as for orienting and maintaining attention within an auditory space that was previously primed by a vocal emotional event. PMID:27242420

  19. Measuring effects of voluntary attention: a comparison among predictive arrow, colour, and number cues.

    PubMed

    Olk, Bettina; Tsankova, Elena; Petca, A Raisa; Wilhelm, Adalbert F X

    2014-10-01

    The Posner cueing paradigm is one of the most widely used paradigms in attention research. Importantly, when employing it, it is critical to understand which type of orienting a cue triggers. It has been suggested that large effects elicited by predictive arrow cues reflect an interaction of involuntary and voluntary orienting. This conclusion is based on comparisons of cueing effects of predictive arrows, nonpredictive arrows (involuntary orienting), and predictive numbers (voluntary orienting). Experiment 1 investigated whether this conclusion is restricted to comparisons with number cues and showed similar results to those of previous studies, but now for comparisons to predictive colour cues, indicating that the earlier conclusion can be generalized. Experiment 2 assessed whether the size of a cueing effect is related to the ease of deriving direction information from a cue, based on the rationale that effects for arrows may be larger, because it may be easier to process direction information given by symbols such as arrows than that given by other cues. Indeed, direction information is derived faster and more accurately from arrows than from colour and number cues in a direction judgement task, and cueing effects are larger for arrows than for the other cues. Importantly though, performance in the two tasks is not correlated. Hence, the large cueing effects of arrows are not a result of the ease of information processing, but of the types of orienting that the arrows elicit. PMID:24697668

  20. Focused attention vs. crossmodal signals paradigm: deriving predictions from the time-window-of-integration model.

    PubMed

    Colonius, Hans; Diederich, Adele

    2012-01-01

    In the crossmodal signals paradigm (CSP) participants are instructed to respond to a set of stimuli from different modalities, presented more or less simultaneously, as soon as a stimulus from any modality has been detected. In the focused attention paradigm (FAP), on the other hand, responses should only be made to a stimulus from a pre-defined target modality and stimuli from non-target modalities should be ignored. Whichever paradigm is being applied, a typical result is that responses tend to be faster to crossmodal stimuli than to unimodal stimuli, a phenomenon often referred to as "crossmodal interaction." Here, we investigate predictions of the time-window-of-integration (TWIN) modeling framework previously proposed by the authors. It is shown that TWIN makes specific qualitative and quantitative predictions on how the two paradigms differ with respect to the probability of multisensory integration and the amount of response enhancement, including the effect of stimulus intensity ("inverse effectiveness"). Introducing a decision-theoretic framework for TWIN further allows comparing the two paradigms with respect to the predicted optimal time window size and its dependence on the prior probability that the crossmodal stimulus information refers to the same event. In order to test these predictions, experimental studies that systematically compare crossmodal effects under stimulus conditions that are identical except for the CSP-FAP instruction should be performed in the future. PMID:22952460

  1. Top-down Modulation of Neural Activity in Anticipatory Visual Attention: Control Mechanisms Revealed by Simultaneous EEG-fMRI.

    PubMed

    Liu, Yuelu; Bengson, Jesse; Huang, Haiqing; Mangun, George R; Ding, Mingzhou

    2016-02-01

    In covert visual attention, frontoparietal attention control areas are thought to issue signals to selectively bias sensory neurons to facilitate behaviorally relevant information and suppress distraction. We investigated the relationship between activity in attention control areas and attention-related modulation of posterior alpha activity using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging in humans during cued visual-spatial attention. Correlating single-trial EEG alpha power with blood-oxygen-level dependent (BOLD) activity, we found that BOLD in the intraparietal sulcus (IPS) and left middle frontal gyrus was inversely correlated with occipital alpha power. Importantly, in IPS, inverse correlations were stronger for alpha within the hemisphere contralateral to the attended hemifield, implicating the IPS in the enhancement of task-relevant sensory areas. Positive BOLD-alpha correlations were observed in sensorimotor cortices and the default mode network, suggesting a mechanism of active suppression over task-irrelevant areas. The magnitude of cue-induced alpha lateralization was positively correlated with BOLD in dorsal anterior cingulate cortex and dorsolateral prefrontal cortex, implicating a role of executive control in attention. These results show that IPS and frontal executive areas are the main sources of biasing influences on task-relevant visual cortex, whereas task-irrelevant default mode network and sensorimotor cortex are inhibited during visual attention.

  2. Modulation of spatial attention by goals, statistical learning, and monetary reward.

    PubMed

    Jiang, Yuhong V; Sha, Li Z; Remington, Roger W

    2015-10-01

    This study documented the relative strength of task goals, visual statistical learning, and monetary reward in guiding spatial attention. Using a difficult T-among-L search task, we cued spatial attention to one visual quadrant by (i) instructing people to prioritize it (goal-driven attention), (ii) placing the target frequently there (location probability learning), or (iii) associating that quadrant with greater monetary gain (reward-based attention). Results showed that successful goal-driven attention exerted the strongest influence on search RT. Incidental location probability learning yielded a smaller though still robust effect. Incidental reward learning produced negligible guidance for spatial attention. The 95 % confidence intervals of the three effects were largely nonoverlapping. To understand these results, we simulated the role of location repetition priming in probability cuing and reward learning. Repetition priming underestimated the strength of location probability cuing, suggesting that probability cuing involved long-term statistical learning of how to shift attention. Repetition priming provided a reasonable account for the negligible effect of reward on spatial attention. We propose a multiple-systems view of spatial attention that includes task goals, search habit, and priming as primary drivers of top-down attention.

  3. Modulation of spatial attention by goals, statistical learning, and monetary reward

    PubMed Central

    Sha, Li Z.; Remington, Roger W.

    2015-01-01

    This study documented the relative strength of task goals, visual statistical learning, and monetary reward in guiding spatial attention. Using a difficult T-among-L search task, we cued spatial attention to one visual quadrant by (i) instructing people to prioritize it (goal-driven attention), (ii) placing the target frequently there (location probability learning), or (iii) associating that quadrant with greater monetary gain (reward-based attention). Results showed that successful goal-driven attention exerted the strongest influence on search RT. Incidental location probability learning yielded a smaller though still robust effect. Incidental reward learning produced negligible guidance for spatial attention. The 95 % confidence intervals of the three effects were largely nonoverlapping. To understand these results, we simulated the role of location repetition priming in probability cuing and reward learning. Repetition priming underestimated the strength of location probability cuing, suggesting that probability cuing involved long-term statistical learning of how to shift attention. Repetition priming provided a reasonable account for the negligible effect of reward on spatial attention. We propose a multiple-systems view of spatial attention that includes task goals, search habit, and priming as primary drivers of top-down attention. PMID:26105657

  4. Captured by the pain: pain steady-state evoked potentials are not modulated by selective spatial attention.

    PubMed

    Blöchl, Maria; Franz, Marcel; Miltner, Wolfgang H R; Weiss, Thomas

    2015-04-01

    Attention has been shown to affect the neural processing of pain. However, the exact mechanisms underlying this modulation remain unknown. Here, we used a new method called pain steady-state evoked potentials (PSSEPs) to investigate whether selective spatial attention affects EEG responses to tonic painful stimuli. In general, steady-state evoked potentials reflect changes in the EEG spectrum at a certain frequency that correspond to the frequency of a train of applied stimuli. In this study, high intensity transcutaneous electrical stimulation was delivered to both hands simultaneously with 31 Hz and 37 Hz, respectively. Subject׳s attention was directed to one of the two trains of stimulation in order to detect a small gap that was occasionally interspersed into the stimulus trains. Thereby, they had to ignore the stimulation applied to the other hand. Results show that PSSEPs were induced at 31 Hz and 37 Hz at frontal and central electrodes. PSSEPs occurred contralaterally to the respective hand stimulated with that frequency. Surprisingly, the magnitude of PSSEPs was not modulated by spatial attention towards one of the two stimuli. Our results indicate that attention can hardly be shifted between two simultaneously applied tonic painful stimulations.

  5. Cortical Brain Activity Reflecting Attentional Biasing Toward Reward-Predicting Cues Covaries with Economic Decision-Making Performance.

    PubMed

    San Martín, René; Appelbaum, Lawrence G; Huettel, Scott A; Woldorff, Marty G

    2016-01-01

    Adaptive choice behavior depends critically on identifying and learning from outcome-predicting cues. We hypothesized that attention may be preferentially directed toward certain outcome-predicting cues. We studied this possibility by analyzing event-related potential (ERP) responses in humans during a probabilistic decision-making task. Participants viewed pairs of outcome-predicting visual cues and then chose to wager either a small (i.e., loss-minimizing) or large (i.e., gain-maximizing) amount of money. The cues were bilaterally presented, which allowed us to extract the relative neural responses to each cue by using a contralateral-versus-ipsilateral ERP contrast. We found an early lateralized ERP response, whose features matched the attention-shift-related N2pc component and whose amplitude scaled with the learned reward-predicting value of the cues as predicted by an attention-for-reward model. Consistently, we found a double dissociation involving the N2pc. Across participants, gain-maximization positively correlated with the N2pc amplitude to the most reliable gain-predicting cue, suggesting an attentional bias toward such cues. Conversely, loss-minimization was negatively correlated with the N2pc amplitude to the most reliable loss-predicting cue, suggesting an attentional avoidance toward such stimuli. These results indicate that learned stimulus-reward associations can influence rapid attention allocation, and that differences in this process are associated with individual differences in economic decision-making performance. PMID:25139941

  6. Reconciling the influence of predictiveness and uncertainty on stimulus salience: a model of attention in associative learning.

    PubMed

    Esber, Guillem R; Haselgrove, Mark

    2011-09-01

    Theories of selective attention in associative learning posit that the salience of a cue will be high if the cue is the best available predictor of reinforcement (high predictiveness). In contrast, a different class of attentional theory stipulates that the salience of a cue will be high if the cue is an inaccurate predictor of reinforcement (high uncertainty). Evidence in support of these seemingly contradictory propositions has led to: (i) the development of hybrid attentional models that assume the coexistence of separate, predictiveness-driven and uncertainty-driven mechanisms of changes in cue salience; and (ii) a surge of interest in identifying the neural circuits underpinning these mechanisms. Here, we put forward a formal attentional model of learning that reconciles the roles of predictiveness and uncertainty in salience modification. The issues discussed are relevant to psychologists, behavioural neuroscientists and neuroeconomists investigating the roles of predictiveness and uncertainty in behaviour.

  7. Reconciling the influence of predictiveness and uncertainty on stimulus salience: a model of attention in associative learning

    PubMed Central

    Esber, Guillem R.; Haselgrove, Mark

    2011-01-01

    Theories of selective attention in associative learning posit that the salience of a cue will be high if the cue is the best available predictor of reinforcement (high predictiveness). In contrast, a different class of attentional theory stipulates that the salience of a cue will be high if the cue is an inaccurate predictor of reinforcement (high uncertainty). Evidence in support of these seemingly contradictory propositions has led to: (i) the development of hybrid attentional models that assume the coexistence of separate, predictiveness-driven and uncertainty-driven mechanisms of changes in cue salience; and (ii) a surge of interest in identifying the neural circuits underpinning these mechanisms. Here, we put forward a formal attentional model of learning that reconciles the roles of predictiveness and uncertainty in salience modification. The issues discussed are relevant to psychologists, behavioural neuroscientists and neuroeconomists investigating the roles of predictiveness and uncertainty in behaviour. PMID:21653585

  8. Predicting methylphenidate response in attention deficit hyperactivity disorder: a preliminary study.

    PubMed

    Johnston, Blair A; Coghill, David; Matthews, Keith; Steele, J Douglas

    2015-01-01

    Methylphenidate (MPH) is established as the main pharmacological treatment for patients with attention deficit hyperactivity disorder (ADHD). Whilst MPH is generally a highly effective treatment, not all patients respond, and some experience adverse reactions. Currently, there is no reliable method to predict how patients will respond, other than by exposure to a trial of medication. In this preliminary study, we sought to investigate whether an accurate predictor of clinical response to methylphenidate could be developed for individual patients, using sociodemographic, clinical and neuropsychological measures. Of the 43 boys with ADHD included in this proof-of-concept study, 30 were classed as responders and 13 as non-responders to MPH, with no significant differences in age nor verbal intelligence quotient (IQ) between the groups. Here we report the application of a multivariate analysis approach to the prediction of clinical response to MPH, which achieved an accuracy of 77% (p = 0.005). The most important variables to the classifier were performance on a 'go/no go' task and comorbid conduct disorder. This preliminary study suggested that further investigation is merited. Achieving a highly significant accuracy of 77% for the prediction of MPH response is an encouraging step towards finding a reliable and clinically useful method that could minimise the number of children needlessly being exposed to MPH.

  9. Modulation of attentional inhibition by norepinephrine and cortisol after psychological stress.

    PubMed

    Skosnik, P D; Chatterton, R T; Swisher, T; Park, S

    2000-04-01

    Two of the most salient physiological responses to stress are increased norepinephrine (NE) and cortisol (CORT) activities. However, it is unclear how these neurochemical events affect cognition, especially attention. We examined the effects of mild psychological stress on selective attention, as assessed by the negative priming (NP) paradigm. Salivary measures of the stress hormone CORT and alpha-amylase (a correlate of NE) were assayed to probe the relationship between the stress response and attentional inhibition. Healthy subjects (N = 20) engaged in the attention task, which was then followed by 15 min of a stressful video game before a return to the attentional task. Baseline saliva samples were obtained before the experiment began, 1 min after the video-game stressor, and 20 min post-stress. Subjects showed a significant reduction in NP and a decrease in reaction time (RT) after the video game. Moreover, alpha-amylase levels increased significantly after the stressor, indicating the role of NE in the acute stress response. While CORT levels remained unchanged after stress, CORT correlated significantly with both NP scores and RT after the stressor. These results imply that mild psychological stress can significantly alter attentional processes. Given the increase in alpha-amylase and the correlation between attention and CORT after stress, it seems likely that attentional processes are under tight control by brain systems which mediate the fight-or-flight response.

  10. Modulation of Attentional Blink with Emotional Faces in Typical Development and in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Yerys, Benjamin E.; Ruiz, Ericka; Strang, John; Sokoloff, Jennifer; Kenworthy, Lauren; Vaidya, Chandan J.

    2013-01-01

    Background: The attentional blink (AB) phenomenon was used to assess the effect of emotional information on early visual attention in typically developing (TD) children and children with autism spectrum disorders (ASD). The AB effect is the momentary perceptual unawareness that follows target identification in a rapid serial visual processing…

  11. Attentional Modulation of Masked Repetition and Categorical Priming in Young and Older Adults

    ERIC Educational Resources Information Center

    Fabre, Ludovic; Lemaire, Patrick; Grainger, Jonathan

    2007-01-01

    Three experiments examined the effects of temporal attention and aging on masked repetition and categorical priming for numbers and words. Participants' temporal attention was manipulated by varying the stimulus onset asynchrony (i.e., constant or variable SOA). In Experiment 1, participants performed a parity judgment task and a lexical decision…

  12. The prelimbic cortex uses contextual cues to modulate responding towards predictive stimuli during fear renewal.

    PubMed

    Sharpe, Melissa; Killcross, Simon

    2015-02-01

    Previous research suggests the prelimbic (PL) cortex is involved in expression of conditioned fear (Burgos-Robles, Vidal-Gonzalez, & Quirk, 2009; Corcoran & Quirk, 2007). However, there is a long history of research in the appetitive domain which implicates this region in using higher-order cues to modulate a behavioural response (Birrell & Brown, 2000; Floresco, Block, & Tse, 2008; Marquis, Killcross, & Haddon, 2007; Sharpe & Killcross, 2014). For example, the PL cortex is necessary to allow animals to use contextual cues to disambiguate response conflict in ambiguous circumstances (Marquis et al., 2007). Using an ABA fear renewal procedure, we assessed the role of the PL cortex in using contextual cues to modulate a response towards a conditioned stimulus (CS) in an aversive setting. We found that pre-training lesions of the PL cortex did not impact on the expression or extinction of conditioned fear. Rather, they selectively abolished renewal. Functional inactivation of the PL cortex during extinction did not disrupt the subsequent renewal of conditioned fear or the ability of animals to exhibit fear towards a CS during the extinction session. However, PL inactivation during the renewal test session disrupted the ability of animals to demonstrate a reinstatement of responding in the renewal context. An analysis of orienting responses showed that renewal deficits were accompanied by a lack of change in attentional responding towards the CS. These data suggest the PL cortex uses contextual cues to modulate both a behavioural and an attentional response during aversive procedures. We argue that the role of the PL cortex in the expression of conditioned fear is to use higher-order information to modulate responding towards predictive cues in ambiguous circumstance. PMID:25464011

  13. Modulation of selective attention by polarity-specific tDCS effects.

    PubMed

    Pecchinenda, Anna; Ferlazzo, Fabio; Lavidor, Michal

    2015-02-01

    Selective attention relies on working memory to maintain an attention set of task priorities. Consequently, selective attention is more efficient when working memory resources are not depleted. However, there is some evidence that distractors are processed even when working memory load is low. We used tDCS to assess whether boosting the activity of the Dorsolateral Prefrontal Cortex (DLPFC), involved in selective attention and working memory, would reduce interference from emotional distractors. Findings showed that anodal tDCS over the DLPFC was not sufficient to reduce interference from angry distractors. In contrast, cathodal tDCS over the DLPFC reduced interference from happy distractors. These findings show that altering the DLPFC activity is not sufficient to establish top-down control and increase selective attention efficiency. Although, when the neural signal in the DLPFC is altered by cathodal tDCS, interference from emotional distractors is reduced, leading to an improved performance.

  14. Attentional bias towards and away from fearful faces is modulated by developmental amygdala damage.

    PubMed

    Pishnamazi, Morteza; Tafakhori, Abbas; Loloee, Sogol; Modabbernia, Amirhossein; Aghamollaii, Vajiheh; Bahrami, Bahador; Winston, Joel S

    2016-08-01

    The amygdala is believed to play a major role in orienting attention towards threat-related stimuli. However, behavioral studies on amygdala-damaged patients have given inconsistent results-variously reporting decreased, persisted, and increased attention towards threat. Here we aimed to characterize the impact of developmental amygdala damage on emotion perception and the nature and time-course of spatial attentional bias towards fearful faces. We investigated SF, a 14-year-old with selective bilateral amygdala damage due to Urbach-Wiethe disease (UWD), and ten healthy controls. Participants completed a fear sensitivity questionnaire, facial expression classification task, and dot-probe task with fearful or neutral faces for spatial cueing. Three cue durations were used to assess the time-course of attentional bias. SF expressed significantly lower fear sensitivity, and showed a selective impairment in classifying fearful facial expressions. Despite this impairment in fear recognition, very brief (100 msec) fearful cues could orient SF's spatial attention. In healthy controls, the attentional bias emerged later and persisted longer. SF's attentional bias was due solely to facilitated engagement to fear, while controls showed the typical phenomenon of difficulty in disengaging from fear. Our study is the first to demonstrate the separable effects of amygdala damage on engagement and disengagement of spatial attention. The findings indicate that multiple mechanisms contribute in biasing attention towards fear, which vary in their timing and dependence on amygdala integrity. It seems that the amygdala is not essential for rapid attention to emotion, but probably has a role in assessment of biological relevance. PMID:27173975

  15. Involuntary attention enhances identification accuracy for unmasked low contrast letters using non-predictive peripheral cues.

    PubMed

    Pack, Weston; Carney, Thom; Klein, Stanley A

    2013-08-30

    There is controversy regarding whether or not involuntary attention improves response accuracy at a cued location when the cue is non-predictive and if these cueing effects are dependent on backward masking. Various perceptual and decisional mechanisms of performance enhancement have been proposed, such as signal enhancement, noise reduction, spatial uncertainty reduction, and decisional processes. Herein we review a recent report of mask-dependent accuracy improvements with low contrast stimuli and demonstrate that the experiments contained stimulus artifacts whereby the cue impaired perception of low contrast stimuli, leading to an absence of improved response accuracy with unmasked stimuli. Our experiments corrected these artifacts by implementing an isoluminant cue and increasing its distance relative to the targets. The results demonstrate that cueing effects are robust for unmasked stimuli presented in the periphery, resolving some of the controversy concerning cueing enhancement effects from involuntary attention and mask dependency. Unmasked low contrast and/or short duration stimuli as implemented in these experiments may have a short enough iconic decay that the visual system functions similarly as if a mask were present leading to improved accuracy with a valid cue.

  16. Predicting Aggressive Tendencies by Visual Attention Bias Associated with Hostile Emotions

    PubMed Central

    Lin, Ping-I; Hsieh, Cheng-Da; Juan, Chi-Hung; Hossain, Md Monir; Erickson, Craig A.; Lee, Yang-Han; Su, Mu-Chun

    2016-01-01

    The goal of the current study is to clarify the relationship between social information processing (e.g., visual attention to cues of hostility, hostility attribution bias, and facial expression emotion labeling) and aggressive tendencies. Thirty adults were recruited in the eye-tracking study that measured various components in social information processing. Baseline aggressive tendencies were measured using the Buss-Perry Aggression Questionnaire (AQ). Visual attention towards hostile objects was measured as the proportion of eye gaze fixation duration on cues of hostility. Hostility attribution bias was measured with the rating results for emotions of characters in the images. The results show that the eye gaze duration on hostile characters was significantly inversely correlated with the AQ score and less eye contact with an angry face. The eye gaze duration on hostile object was not significantly associated with hostility attribution bias, although hostility attribution bias was significantly positively associated with the AQ score. Our findings suggest that eye gaze fixation time towards non-hostile cues may predict aggressive tendencies. PMID:26901770

  17. Cognitive trait anxiety, situational stress, and mental effort predict shifting efficiency: Implications for attentional control theory.

    PubMed

    Edwards, Elizabeth J; Edwards, Mark S; Lyvers, Michael

    2015-06-01

    Attentional control theory (ACT) predicts that trait anxiety and situational stress interact to impair performance on tasks that involve attentional shifting. The theory suggests that anxious individuals recruit additional effort to prevent shortfalls in performance effectiveness (accuracy), with deficits becoming evident in processing efficiency (the relationship between accuracy and time taken to perform the task). These assumptions, however, have not been systematically tested. The relationship between cognitive trait anxiety, situational stress, and mental effort in a shifting task (Wisconsin Card Sorting Task) was investigated in 90 participants. Cognitive trait anxiety was operationalized using questionnaire scores, situational stress was manipulated through ego threat instructions, and mental effort was measured using a visual analogue scale. Dependent variables were performance effectiveness (an inverse proportion of perseverative errors) and processing efficiency (an inverse proportion of perseverative errors divided by response time on perseverative error trials). The predictors were not associated with performance effectiveness; however, we observed a significant 3-way interaction on processing efficiency. At higher mental effort (+1 SD), higher cognitive trait anxiety was associated with poorer efficiency independently of situational stress, whereas at lower effort (-1 SD), this relationship was highly significant and most pronounced for those in the high-stress condition. These results are important because they provide the first systematic test of the relationship between trait anxiety, situational stress, and mental effort on shifting performance. The data are also consistent with the notion that effort moderates the relationship between anxiety and shifting efficiency, but not effectiveness.

  18. Predicting Aggressive Tendencies by Visual Attention Bias Associated with Hostile Emotions.

    PubMed

    Lin, Ping-I; Hsieh, Cheng-Da; Juan, Chi-Hung; Hossain, Md Monir; Erickson, Craig A; Lee, Yang-Han; Su, Mu-Chun

    2016-01-01

    The goal of the current study is to clarify the relationship between social information processing (e.g., visual attention to cues of hostility, hostility attribution bias, and facial expression emotion labeling) and aggressive tendencies. Thirty adults were recruited in the eye-tracking study that measured various components in social information processing. Baseline aggressive tendencies were measured using the Buss-Perry Aggression Questionnaire (AQ). Visual attention towards hostile objects was measured as the proportion of eye gaze fixation duration on cues of hostility. Hostility attribution bias was measured with the rating results for emotions of characters in the images. The results show that the eye gaze duration on hostile characters was significantly inversely correlated with the AQ score and less eye contact with an angry face. The eye gaze duration on hostile object was not significantly associated with hostility attribution bias, although hostility attribution bias was significantly positively associated with the AQ score. Our findings suggest that eye gaze fixation time towards non-hostile cues may predict aggressive tendencies. PMID:26901770

  19. Predictive coding and multisensory integration: an attentional account of the multisensory mind

    PubMed Central

    Talsma, Durk

    2015-01-01

    Multisensory integration involves a host of different cognitive processes, occurring at different stages of sensory processing. Here I argue that, despite recent insights suggesting that multisensory interactions can occur at very early latencies, the actual integration of individual sensory traces into an internally consistent mental representation is dependent on both top–down and bottom–up processes. Moreover, I argue that this integration is not limited to just sensory inputs, but that internal cognitive processes also shape the resulting mental representation. Studies showing that memory recall is affected by the initial multisensory context in which the stimuli were presented will be discussed, as well as several studies showing that mental imagery can affect multisensory illusions. This empirical evidence will be discussed from a predictive coding perspective, in which a central top–down attentional process is proposed to play a central role in coordinating the integration of all these inputs into a coherent mental representation. PMID:25859192

  20. Cholinergic modulation of the medial prefrontal cortex: the role of nicotinic receptors in attention and regulation of neuronal activity

    PubMed Central

    Bloem, Bernard; Poorthuis, Rogier B.; Mansvelder, Huibert D.

    2014-01-01

    Acetylcholine (ACh) release in the medial prefrontal cortex (mPFC) is crucial for normal cognitive performance. Despite the fact that many have studied how ACh affects neuronal processing in the mPFC and thereby influences attention behavior, there is still a lot unknown about how this occurs. Here we will review the evidence that cholinergic modulation of the mPFC plays a role in attention and we will summarize the current knowledge about the role between ACh receptors (AChRs) and behavior and how ACh receptor activation changes processing in the cortical microcircuitry. Recent evidence implicates fast phasic release of ACh in cue detection and attention. This review will focus mainly on the fast ionotropic nicotinic receptors and less on the metabotropic muscarinic receptors. Finally, we will review limitations of the existing studies and address how innovative technologies might push the field forward in order to gain understanding into the relation between ACh, neuronal activity and behavior. PMID:24653678

  1. Attention Strongly Modulates Reliability of Neural Responses to Naturalistic Narrative Stimuli.

    PubMed

    Ki, Jason J; Kelly, Simon P; Parra, Lucas C

    2016-03-01

    Attentional engagement is a major determinant of how effectively we gather information through our senses. Alongside the sheer growth in the amount and variety of information content that we are presented with through modern media, there is increased variability in the degree to which we "absorb" that information. Traditional research on attention has illuminated the basic principles of sensory selection to isolated features or locations, but it provides little insight into the neural underpinnings of our attentional engagement with modern naturalistic content. Here, we show in human subjects that the reliability of an individual's neural responses with respect to a larger group provides a highly robust index of the level of attentional engagement with a naturalistic narrative stimulus. Specifically, fast electroencephalographic evoked responses were more strongly correlated across subjects when naturally attending to auditory or audiovisual narratives than when attention was directed inward to a mental arithmetic task during stimulus presentation. This effect was strongest for audiovisual stimuli with a cohesive narrative and greatly reduced for speech stimuli lacking meaning. For compelling audiovisual narratives, the effect is remarkably strong, allowing perfect discrimination between attentional state across individuals. Control experiments rule out possible confounds related to altered eye movement trajectories or order of presentation. We conclude that reliability of evoked activity reproduced across subjects viewing the same movie is highly sensitive to the attentional state of the viewer and listener, which is aided by a cohesive narrative. PMID:26961961

  2. Painful faces-induced attentional blink modulated by top-down and bottom-up mechanisms.

    PubMed

    Zheng, Chun; Wang, Jin-Yan; Luo, Fei

    2015-01-01

    Pain-related stimuli can capture attention in an automatic (bottom-up) or intentional (top-down) fashion. Previous studies have examined attentional capture by pain-related information using spatial attention paradigms that involve mainly a bottom-up mechanism. In the current study, we investigated the pain information-induced attentional blink (AB) using a rapid serial visual presentation (RSVP) task, and compared the effects of task-irrelevant and task-relevant pain distractors. Relationships between accuracy of target identification and individual traits (i.e., empathy and catastrophizing thinking about pain) were also examined. The results demonstrated that task-relevant painful faces had a significant pain information-induced AB effect, whereas task-irrelevant faces showed a near-significant trend of this effect, supporting the notion that pain-related stimuli can influence the temporal dynamics of attention. Furthermore, we found a significant negative correlation between response accuracy and pain catastrophizing score in task-relevant trials. These findings suggest that active scanning of environmental information related to pain produces greater deficits in cognition than does unintentional attention toward pain, which may represent the different ways in which healthy individuals and patients with chronic pain process pain-relevant information. These results may provide insight into the understanding of maladaptive attentional processing in patients with chronic pain. PMID:26082731

  3. Painful faces-induced attentional blink modulated by top–down and bottom–up mechanisms

    PubMed Central

    Zheng, Chun; Wang, Jin-Yan; Luo, Fei

    2015-01-01

    Pain-related stimuli can capture attention in an automatic (bottom–up) or intentional (top–down) fashion. Previous studies have examined attentional capture by pain-related information using spatial attention paradigms that involve mainly a bottom–up mechanism. In the current study, we investigated the pain information-induced attentional blink (AB) using a rapid serial visual presentation (RSVP) task, and compared the effects of task-irrelevant and task-relevant pain distractors. Relationships between accuracy of target identification and individual traits (i.e., empathy and catastrophizing thinking about pain) were also examined. The results demonstrated that task-relevant painful faces had a significant pain information-induced AB effect, whereas task-irrelevant faces showed a near-significant trend of this effect, supporting the notion that pain-related stimuli can influence the temporal dynamics of attention. Furthermore, we found a significant negative correlation between response accuracy and pain catastrophizing score in task-relevant trials. These findings suggest that active scanning of environmental information related to pain produces greater deficits in cognition than does unintentional attention toward pain, which may represent the different ways in which healthy individuals and patients with chronic pain process pain-relevant information. These results may provide insight into the understanding of maladaptive attentional processing in patients with chronic pain. PMID:26082731

  4. Focus on the positive: anxiety modulates the effects of emotional stimuli on hemispheric attention.

    PubMed

    Crump, Caroline; Kishore, S Aakash; Zaidel, Eran

    2013-10-01

    People with high levels of trait anxiety are said to orient attention selectively to threatening stimuli (Bradley, Mogg, White, Groom, & de Bono, 1999; MacLeod, Mathews, & Tata, 1986), but this effect is sometimes difficult to replicate. We suggest a reason for this difficulty is that typical tests of the spatial attention bias in anxiety failed to consider together: (1) the differential effects of positive and threatening stimuli on attention in anxiety, (2) the separate contributions of each hemisphere to the attention bias, and (3) whether the attention bias in anxiety is restricted to orienting or can be observed more strongly in the conflict or alerting networks of attention. We compared the effects of schematic angry, happy, and neutral face cues using a lateralized version of Posner's Attention Network Task (Lateralized Attention Network Test) which distinguishes spatial Orienting Cost (due to an invalid cue; disengagement) from spatial Orienting Benefit (due to a valid cue; hypervigilance), and which considers executive Conflict resolution and Alerting in addition to spatial Orienting in each hemisphere separately. We tested participants with high and low trait anxiety measured by the STAI-TA (Spielberger, Gorsuch, & Lushene, 1983). Surprisingly, happy face cues rather than angry face cues interacted with target visual field and participant level of anxiety. Happy face cues presented to participants with low anxiety elicited maximal Orienting Benefit and minimal Orienting Cost for targets presented to the left visual field. Anxious individuals failed to benefit from happy cues in the left visual field. We suggest that lateralized positive cues can provide a more sensitive index of attention changes in anxiety than is provided by centrally-presented threatening cues.

  5. Attentional modulation of neural processing of shape, color, and velocity in humans

    SciTech Connect

    Corbetta, M.; Miezin, F.M.; Dobmeyer, S.; Shulman, G.L.; Petersen, S.E. )

    1990-06-22

    Positron emission tomography (PET) was used to measure changes in regional cerebral blood flow of normal subjects, while they were discriminating different attributes (shape, color, and velocity) of the same set of visual stimuli. Psychophysical evidence indicated that the sensitivity for discriminating subtle stimulus changes was higher when subjects focused attention on one attribute than when they divided attention among several attributes. Correspondingly, attention enhanced the activity of different regions of extrastriate visual cortex that appear to be specialized for processing information related to the selected attribute.

  6. The attention-weighted sample-size model of visual short-term memory: Attention capture predicts resource allocation and memory load.

    PubMed

    Smith, Philip L; Lilburn, Simon D; Corbett, Elaine A; Sewell, David K; Kyllingsbæk, Søren

    2016-09-01

    We investigated the capacity of visual short-term memory (VSTM) in a phase discrimination task that required judgments about the configural relations between pairs of black and white features. Sewell et al. (2014) previously showed that VSTM capacity in an orientation discrimination task was well described by a sample-size model, which views VSTM as a resource comprised of a finite number of noisy stimulus samples. The model predicts the invariance of [Formula: see text] , the sum of squared sensitivities across items, for displays of different sizes. For phase discrimination, the set-size effect significantly exceeded that predicted by the sample-size model for both simultaneously and sequentially presented stimuli. Instead, the set-size effect and the serial position curves with sequential presentation were predicted by an attention-weighted version of the sample-size model, which assumes that one of the items in the display captures attention and receives a disproportionate share of resources. The choice probabilities and response time distributions from the task were well described by a diffusion decision model in which the drift rates embodied the assumptions of the attention-weighted sample-size model.

  7. The attention-weighted sample-size model of visual short-term memory: Attention capture predicts resource allocation and memory load.

    PubMed

    Smith, Philip L; Lilburn, Simon D; Corbett, Elaine A; Sewell, David K; Kyllingsbæk, Søren

    2016-09-01

    We investigated the capacity of visual short-term memory (VSTM) in a phase discrimination task that required judgments about the configural relations between pairs of black and white features. Sewell et al. (2014) previously showed that VSTM capacity in an orientation discrimination task was well described by a sample-size model, which views VSTM as a resource comprised of a finite number of noisy stimulus samples. The model predicts the invariance of [Formula: see text] , the sum of squared sensitivities across items, for displays of different sizes. For phase discrimination, the set-size effect significantly exceeded that predicted by the sample-size model for both simultaneously and sequentially presented stimuli. Instead, the set-size effect and the serial position curves with sequential presentation were predicted by an attention-weighted version of the sample-size model, which assumes that one of the items in the display captures attention and receives a disproportionate share of resources. The choice probabilities and response time distributions from the task were well described by a diffusion decision model in which the drift rates embodied the assumptions of the attention-weighted sample-size model. PMID:27494766

  8. The fearful-face advantage is modulated by task demands: evidence from the attentional blink.

    PubMed

    Stein, Timo; Peelen, Marius V; Funk, Johanna; Seidl, Katharina N

    2010-02-01

    Fearful faces receive privileged access to awareness relative to happy and nonemotional faces. We investigated whether this advantage depends on currently available attentional resources. In an attentional blink paradigm, observers detected faces presented during the attentional blink period that could depict either a fearful or a happy expression. Perceptual load of the blink-inducing target was manipulated by increasing flanker interference. For the low-load condition, fearful faces were detected more often than happy faces, replicating previous reports. More important, this advantage for fearful faces disappeared for the high-load condition, during which fearful and happy faces were detected equally often. These results suggest that the privileged access of fearful faces to awareness does not occur mandatorily, but instead depends on attentional resources.

  9. Attentional modulation of masked repetition and categorical priming in young and older adults.

    PubMed

    Fabre, Ludovic; Lemaire, Patrick; Grainger, Jonathan

    2007-12-01

    Three experiments examined the effects of temporal attention and aging on masked repetition and categorical priming for numbers and words. Participants' temporal attention was manipulated by varying the stimulus onset asynchrony (i.e., constant or variable SOA). In Experiment 1, participants performed a parity judgment task and a lexical decision task in which categorical priming and repetition priming were, respectively, tested. Experiment 2 used a semantic categorization task testing categorical priming. In Experiment 3, repetition and categorical priming were tested in the same semantic categorization task with the same stimuli. The results of the three experiments showed that masked repetition priming is insensitive to manipulations of temporal attention whereas categorical priming is. Furthermore, no differences were found between young and older adults in repetition priming effects, again contrasting with the categorical priming results for which older adults were more sensitive to attentional manipulations than young adults.

  10. Selective attention modulates visual and haptic repetition priming: effects in aging and Alzheimer's disease.

    PubMed

    Ballesteros, Soledad; Reales, José M; Mayas, Julia; Heller, Morton A

    2008-08-01

    In two experiments, we examined the effect of selective attention at encoding on repetition priming in normal aging and Alzheimer's disease (AD) patients for objects presented visually (experiment 1) or haptically (experiment 2). We used a repetition priming paradigm combined with a selective attention procedure at encoding. Reliable priming was found for both young adults and healthy older participants for visually presented pictures (experiment 1) as well as for haptically presented objects (experiment 2). However, this was only found for attended and not for unattended stimuli. The results suggest that independently of the perceptual modality, repetition priming requires attention at encoding and that perceptual facilitation is maintained in normal aging. However, AD patients did not show priming for attended stimuli, or for unattended visual or haptic objects. These findings suggest an early deficit of selective attention in AD. Results are discussed from a cognitive neuroscience approach.

  11. Top-down attentional processes modulate the coding of atypical biological motion kinematics in the absence of motor signals.

    PubMed

    Hayes, Spencer J; Roberts, James W; Elliott, Digby; Bennett, Simon J

    2014-08-01

    The acquisition of sensorimotor parameters that control goal-directed motor behaviors occurs by observing another person in the absence of efferent and afferent motor signals. This is observational practice. During such observation, biological motion properties associated with the observed person are coded into a representation that controls motor learning. Understanding the underlying processes, specifically associated with coding biological motion, has theoretical and practical significance. Here, we examined the following questions. Experiment 1: Are the underlying velocity characteristics associated with observed biological motion kinematics imitated? Experiment 2: Is attention involved in imitating biological motion kinematics? Experiment 3: Can selective attention modulate how biological motion kinematics are imitated/represented? To this end, participants practiced by observing a model performing a movement sequence that contained typical or atypical biological motion kinematics. The differences in kinematics were designed to dissociate the movement constraints of the task and the anatomical constraints of the observer. This way, we examined whether novel motor behaviors are acquired by adopting prototypical movements or coding biological motion. The kinematic analyses indicated the timing and spatial position of peak velocity were represented. Using a dual-task protocol, we attenuated the coding of biological motion kinematics (Experiment 2) and augmented coding using a selective attention protocol (Experiment 3). Findings indicated that velocity characteristics of biological motion kinematics are coded during observational practice, most likely through bottom-up sensorimotor processes. By modulating motion coding using 2 attentional protocols, we showed that bottom-up processes are influenced by input modulation, which is consistent with top-down control during observational practice.

  12. Attention to irrelevant contexts decreases as training increases: Evidence from eye-fixations in a human predictive learning task.

    PubMed

    Aristizabal, José A; Ramos-Álvarez, Manuel M; Callejas-Aguilera, José E; Rosas, Juan M

    2016-03-01

    Participants were trained in a human predictive learning task in which they had to predict whether the ingestion of a given food (cue) by the imaginary customer of an imaginary restaurant (context) was followed by gastric malaise (outcome). One food was always followed by gastric malaise in one of the contexts, while other foods were not followed by gastric malaise in the same, or in an alternative context. Predictive responses and eye-fixations were recorded throughout the 48 training trials with each cue involved in the task. In agreement with the predictions of the Attentional Theory of Context Processing, attention to the contexts measured through eye-fixations decreased while attention to the cues increased as training progressed. The results of this study give support to the idea that contexts are actively processed at the beginning of acquisition, and that this processing decreases as training increases.

  13. Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

    PubMed Central

    Lecaignard, Françoise; Bertrand, Olivier; Gimenez, Gérard; Mattout, Jérémie; Caclin, Anne

    2015-01-01

    Deviant stimuli, violating regularities in a sensory environment, elicit the mismatch negativity (MMN), largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience) are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities. PMID:26441602

  14. Dissociated α-Band Modulations in the Dorsal and Ventral Visual Pathways in Visuospatial Attention and Perception

    PubMed Central

    Capilla, Almudena; Schoffelen, Jan-Mathijs; Paterson, Gavin; Thut, Gregor; Gross, Joachim

    2014-01-01

    Modulations of occipito-parietal α-band (8–14 Hz) power that are opposite in direction (α-enhancement vs. α-suppression) and origin of generation (ipsilateral vs. contralateral to the locus of attention) are a robust correlate of anticipatory visuospatial attention. Yet, the neural generators of these α-band modulations, their interdependence across homotopic areas, and their respective contribution to subsequent perception remain unclear. To shed light on these questions, we employed magnetoencephalography, while human volunteers performed a spatially cued detection task. Replicating previous findings, we found α-power enhancement ipsilateral to the attended hemifield and contralateral α-suppression over occipito-parietal sensors. Source localization (beamforming) analysis showed that α-enhancement and suppression were generated in 2 distinct brain regions, located in the dorsal and ventral visual streams, respectively. Moreover, α-enhancement and suppression showed different dynamics and contribution to perception. In contrast to the initial and transient dorsal α-enhancement, α-suppression in ventro-lateral occipital cortex was sustained and influenced subsequent target detection. This anticipatory biasing of ventro-lateral extrastriate α-activity probably reflects increased receptivity in the brain region specialized in processing upcoming target features. Our results add to current models on the role of α-oscillations in attention orienting by showing that α-enhancement and suppression can be dissociated in time, space, and perceptual relevance. PMID:23118197

  15. Predicting Attention to Local Television News: Need for Cognition and Motives for Viewing.

    ERIC Educational Resources Information Center

    Perse, Elizabeth M.

    1992-01-01

    Examines associations between local news viewing motives and attention to government reports or to sports reports. Identifies significant connections between need for cognition, utilitarian local news viewing motives, and attention to government news reports. Finds attention to sports news explained only by respondent sex. Discusses implications…

  16. A model for attentional information routing through coherence predicts biased competition and multistable perception

    PubMed Central

    Ernst, Udo Alexander; Pawelzik, Klaus Richard

    2015-01-01

    Selective attention allows to focus on relevant information and to ignore distracting features of a visual scene. These principles of information processing are reflected in response properties of neurons in visual area V4: if a neuron is presented with two stimuli in its receptive field, and one is attended, it responds as if the nonattended stimulus was absent (biased competition). In addition, when the luminance of the two stimuli is temporally and independently varied, local field potentials are correlated with the modulation of the attended stimulus and not, or much less, correlated with the nonattended stimulus (information routing). To explain these results in one coherent framework, we present a two-layer spiking cortical network model with distance-dependent lateral connectivity and converging feed-forward connections. With oscillations arising inherently from the network structure, our model reproduces both experimental observations. Hereby, lateral interactions and shifts of relative phases between sending and receiving layers (communication through coherence) are identified as the main mechanisms underlying both biased competition as well as selective routing. Exploring the parameter space, we show that the effects are robust and prevalent over a broad range of parameters. In addition, we identify the strength of lateral inhibition in the first model layer as crucial for determining the working regime of the system: increasing lateral inhibition allows a transition from a network configuration with mixed representations to one with bistable representations of the competing stimuli. The latter is discussed as a possible neural correlate of multistable perception phenomena such as binocular rivalry. PMID:26108958

  17. Right Hand Presence Modulates Shifts of Exogenous Visuospatial Attention in Near Perihand Space

    ERIC Educational Resources Information Center

    Lloyd, Donna M.; Azanon, Elena; Poliakoff, Ellen

    2010-01-01

    To investigate attentional shifting in perihand space, we measured performance on a covert visual orienting task under different hand positions. Participants discriminated visual shapes presented on a screen and responded using footpedals placed under their right foot. With the right hand positioned by the right side of the screen, mean cueing…

  18. Attentional Modulation of Visual-Evoked Potentials by Threat: Investigating the Effect of Evolutionary Relevance

    ERIC Educational Resources Information Center

    Brown, Christopher; El-Deredy, Wael; Blanchette, Isabelle

    2010-01-01

    In dot-probe tasks, threatening cues facilitate attention to targets and enhance the amplitude of the target P1 peak of the visual-evoked potential. While theories have suggested that evolutionarily relevant threats should obtain preferential neural processing, this has not been examined empirically. In this study we examined the effects of…

  19. Self-Alert Training: Volitional Modulation of Autonomic Arousal Improves Sustained Attention

    ERIC Educational Resources Information Center

    O'Connell, Redmond G.; Bellgrove, Mark A.; Dockree, Paul M.; Lau, Adam; Fitzgerald, Michael; Robertson, Ian H.

    2008-01-01

    The present study examines a new alertness training strategy (Self-Alert Training, SAT) designed to explore the relationship between the top-down control processes governing arousal and sustained attention. In order to maximally target frontal control systems SAT combines a previously validated behavioural self-alerting technique [Robertson, I.…

  20. Attentional modulation of informational masking on early cortical representations of speech signals.

    PubMed

    Zhang, Changxin; Arnott, Stephen R; Rabaglia, Cristina; Avivi-Reich, Meital; Qi, James; Wu, Xihong; Li, Liang; Schneider, Bruce A

    2016-01-01

    To recognize speech in a noisy auditory scene, listeners need to perceptually segregate the target talker's voice from other competing sounds (stream segregation). A number of studies have suggested that the attentional demands placed on listeners increase as the acoustic properties and informational content of the competing sounds become more similar to that of the target voice. Hence we would expect attentional demands to be considerably greater when speech is masked by speech than when it is masked by steady-state noise. To investigate the role of attentional mechanisms in the unmasking of speech sounds, event-related potentials (ERPs) were recorded to a syllable masked by noise or competing speech under both active (the participant was asked to respond when the syllable was presented) or passive (no response was required) listening conditions. The results showed that the long-latency auditory response to a syllable (/bi/), presented at different signal-to-masker ratios (SMRs), was similar in both passive and active listening conditions, when the masker was a steady-state noise. In contrast, a switch from the passive listening condition to the active one, when the masker was two-talker speech, significantly enhanced the ERPs to the syllable. These results support the hypothesis that the need to engage attentional mechanisms in aid of scene analysis increases as the similarity (both acoustic and informational) between the target speech and the competing background sounds increases.

  1. Social and Nonsocial Content Differentially Modulates Visual Attention and Autonomic Arousal in Rhesus Macaques

    PubMed Central

    Machado, Christopher J.; Bliss-Moreau, Eliza; Platt, Michael L.; Amaral, David G.

    2011-01-01

    The sophisticated analysis of gestures and vocalizations, including assessment of their emotional valence, helps group-living primates efficiently navigate their social environment. Deficits in social information processing and emotion regulation are important components of many human psychiatric illnesses, such as autism, schizophrenia and social anxiety disorder. Analyzing the neurobiology of social information processing and emotion regulation requires a multidisciplinary approach that benefits from comparative studies of humans and animal models. However, many questions remain regarding the relationship between visual attention and arousal while processing social stimuli. Using noninvasive infrared eye-tracking methods, we measured the visual social attention and physiological arousal (pupil diameter) of adult male rhesus monkeys (Macaca mulatta) as they watched social and nonsocial videos. We found that social videos, as compared to nonsocial videos, captured more visual attention, especially if the social signals depicted in the videos were directed towards the subject. Subject-directed social cues and nonsocial nature documentary footage, compared to videos showing conspecifics engaging in naturalistic social interactions, generated larger pupil diameters (indicating heightened sympathetic arousal). These findings indicate that rhesus monkeys will actively engage in watching videos of various kinds. Moreover, infrared eye tracking technology provides a mechanism for sensitively gauging the social interest of presented stimuli. Adult male rhesus monkeys' visual attention and physiological arousal do not always trend in the same direction, and are likely influenced by the content and novelty of a particular visual stimulus. This experiment creates a strong foundation for future experiments that will examine the neural network responsible for social information processing in nonhuman primates. Such studies may provide valuable information relevant to

  2. Visual statistical learning is not reliably modulated by selective attention to isolated events

    PubMed Central

    Musz, Elizabeth; Weber, Matthew J.; Thompson-Schill, Sharon L.

    2014-01-01

    Recent studies of visual statistical learning (VSL) indicate that the visual system can automatically extract temporal and spatial relationships between objects. We report several attempts to replicate and extend earlier work (Turk-Browne et al., 2005) in which observers performed a cover task on one of two interleaved stimulus sets, resulting in learning of temporal relationships that occur in the attended stream, but not those present in the unattended stream. Across four experiments, we exposed observers to a similar or identical familiarization protocol, directing attention to one of two interleaved stimulus sets; afterward, we assessed VSL efficacy for both sets using either implicit response-time measures or explicit familiarity judgments. In line with prior work, we observe learning for the attended stimulus set. However, unlike previous reports, we also observe learning for the unattended stimulus set. When instructed to selectively attend to only one of the stimulus sets and ignore the other set, observers could extract temporal regularities for both sets. Our efforts to experimentally decrease this effect by changing the cover task (Experiment 1) or the complexity of the statistical regularities (Experiment 3) were unsuccessful. A fourth experiment using a different assessment of learning likewise failed to show an attentional effect. Simulations drawing random samples our first three experiments (n=64) confirm that the distribution of attentional effects in our sample closely approximates the null. We offer several potential explanations for our failure to replicate earlier findings, and discuss how our results suggest limiting conditions on the relevance of attention to VSL. PMID:25172196

  3. Beyond pleasure and arousal: appetitive erotic stimuli modulate electrophysiological brain correlates of early attentional processing.

    PubMed

    Kuhr, Benjamin; Schomberg, Jessica; Gruber, Thomas; Quirin, Markus

    2013-03-27

    Previous studies investigating affective reactions to pictures that elicit a specific effect have mainly focused on the dimensions valence and arousal. Using an event-related picture-viewing paradigm in electroencephalography, we investigated whether erotica - that is appetitive, evolutionarily relevant stimuli - have effects on early stages of attentional processing that are distinct from those of other positive and arousing stimuli. Seventeen male students viewed arousing photos of erotic, nude women or pictures of extreme sport scenes, as well as control pictures of attractive, dressed women or daily activities. Erotic pictures differed from extreme sport pictures not only in late but also in early attentional processes, as indicated by event-related potentials appearing from 130 ms after stimulus onset (P1). The findings suggest (a) that the dimension of appetence should be considered in addition to valence and arousal when investigating psychophysiological reactions to affective-motivational stimuli and (b) that early attentional processing as mirrored by the P1 can be influenced by motivational systems. PMID:23426107

  4. Circadian modulation of dopamine levels and dopaminergic neuron development contributes to attention deficiency and hyperactive behavior.

    PubMed

    Huang, Jian; Zhong, Zhaomin; Wang, Mingyong; Chen, Xifeng; Tan, Yicheng; Zhang, Shuqing; He, Wei; He, Xiong; Huang, Guodong; Lu, Haiping; Wu, Ping; Che, Yi; Yan, Yi-Lin; Postlethwait, John H; Chen, Wenbiao; Wang, Han

    2015-02-11

    Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders in children and adults. While ADHD patients often display circadian abnormalities, the underlying mechanisms are unclear. Here we found that the zebrafish mutant for the circadian gene period1b (per1b) displays hyperactive, impulsive-like, and attention deficit-like behaviors and low levels of dopamine, reminiscent of human ADHD patients. We found that the circadian clock directly regulates dopamine-related genes monoamine oxidase and dopamine β hydroxylase, and acts via genes important for the development or maintenance of dopaminergic neurons to regulate their number and organization in the ventral diencephalic posterior tuberculum. We then found that Per1 knock-out mice also display ADHD-like symptoms and reduced levels of dopamine, thereby showing highly conserved roles of the circadian clock in ADHD. Our studies demonstrate that disruption of a circadian clock gene elicits ADHD-like syndrome. The circadian model for attention deficiency and hyperactive behavior sheds light on ADHD pathogenesis and opens avenues for exploring novel targets for diagnosis and therapy for this common psychiatric disorder.

  5. Circadian Modulation of Dopamine Levels and Dopaminergic Neuron Development Contributes to Attention Deficiency and Hyperactive Behavior

    PubMed Central

    Huang, Jian; Zhong, Zhaomin; Wang, Mingyong; Chen, Xifeng; Tan, Yicheng; Zhang, Shuqing; He, Wei; He, Xiong; Huang, Guodong; Lu, Haiping; Wu, Ping; Che, Yi; Yan, Yi-Lin; Postlethwait, John H.; Chen, Wenbiao

    2015-01-01

    Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders in children and adults. While ADHD patients often display circadian abnormalities, the underlying mechanisms are unclear. Here we found that the zebrafish mutant for the circadian gene period1b (per1b) displays hyperactive, impulsive-like, and attention deficit-like behaviors and low levels of dopamine, reminiscent of human ADHD patients. We found that the circadian clock directly regulates dopamine-related genes monoamine oxidase and dopamine β hydroxylase, and acts via genes important for the development or maintenance of dopaminergic neurons to regulate their number and organization in the ventral diencephalic posterior tuberculum. We then found that Per1 knock-out mice also display ADHD-like symptoms and reduced levels of dopamine, thereby showing highly conserved roles of the circadian clock in ADHD. Our studies demonstrate that disruption of a circadian clock gene elicits ADHD-like syndrome. The circadian model for attention deficiency and hyperactive behavior sheds light on ADHD pathogenesis and opens avenues for exploring novel targets for diagnosis and therapy for this common psychiatric disorder. PMID:25673850

  6. Attention modulates neuronal correlates of interhemispheric integration and global motion perception

    PubMed Central

    Akin, Burak; Ozdem, Ceylan; Eroglu, Seda; Keskin, Dudu Taslak; Fang, Fang; Doerschner, Katja; Kersten, Daniel; Boyaci, Huseyin

    2014-01-01

    In early retinotopic areas of the human visual system, information from the left and right visual hemifields (VHFs) is processed contralaterally in two hemispheres. Despite this segregation, we have the perceptual experience of a unified, coherent, and uninterrupted single visual field. How exactly the visual system integrates information from the two VHFs and achieves this perceptual experience still remains largely unknown. In this study using fMRI, we explored candidate areas that are involved in interhemispheric integration and the perceptual experience of a unified, global motion across VHFs. Stimuli were two-dimensional, computer-generated objects with parts in both VHFs. The retinal image in the left VHF always remained stationary, but in the experimental condition, it appeared to have local motion because of the perceived global motion of the object. This perceptual effect could be weakened by directing the attention away from the global motion through a demanding fixation task. Results show that lateral occipital areas, including the medial temporal complex, play an important role in the process of perceptual experience of a unified global motion across VHFs. In early areas, including the lateral geniculate nucleus and V1, we observed correlates of this perceptual experience only when attention is not directed away from the object. These findings reveal effects of attention on interhemispheric integration in motion perception and imply that both the bilateral activity of higher-tier visual areas and feedback mechanisms leading to bilateral activity of early areas play roles in the perceptual experience of a unified visual field. PMID:25349270

  7. Why does working memory capacity predict variation in reading comprehension? On the influence of mind wandering and executive attention.

    PubMed

    McVay, Jennifer C; Kane, Michael J

    2012-05-01

    Some people are better readers than others, and this variation in comprehension ability is predicted by measures of working memory capacity (WMC). The primary goal of this study was to investigate the mediating role of mind-wandering experiences in the association between WMC and normal individual differences in reading comprehension, as predicted by the executive-attention theory of WMC (e.g., Engle & Kane, 2004). We used a latent-variable, structural-equation-model approach, testing skilled adult readers on 3 WMC span tasks, 7 varied reading-comprehension tasks, and 3 attention-control tasks. Mind wandering was assessed using experimenter-scheduled thought probes during 4 different tasks (2 reading, 2 attention-control). The results support the executive-attention theory of WMC. Mind wandering across the 4 tasks loaded onto a single latent factor, reflecting a stable individual difference. Most important, mind wandering was a significant mediator in the relationship between WMC and reading comprehension, suggesting that the WMC-comprehension correlation is driven, in part, by attention control over intruding thoughts. We discuss implications for theories of WMC, attention control, and reading comprehension.

  8. Why Does Working Memory Capacity Predict Variation in Reading Comprehension? On the Influence of Mind Wandering and Executive Attention

    PubMed Central

    McVay, Jennifer C.; Kane, Michael J.

    2012-01-01

    Some people are better readers than others, and this variation in comprehension ability is predicted by measures of working memory capacity (WMC). The primary goal of this study was to investigate the mediating role of mind wandering experiences in the association between WMC and normal individual differences in reading comprehension, as predicted by the executive-attention theory of WMC (e.g., Engle & Kane, 2004). We used a latent-variable, structural-equation-model approach, testing skilled adult readers on three WMC span tasks, seven varied reading comprehension tasks, and three attention-control tasks. Mind wandering was assessed using experimenter-scheduled thought probes during four different tasks (two reading, two attention-control tasks). The results support the executive-attention theory of WMC. Mind wandering across the four tasks loaded onto a single latent factor, reflecting a stable individual difference. Most importantly, mind wandering was a significant mediator in the relationship between WMC and reading comprehension, suggesting that the WMC-comprehension correlation is driven, in part, by attention control over intruding thoughts. We discuss implications for theories of WMC, attention control, and reading comprehension. PMID:21875246

  9. Early Attention and Negative Emotionality Predict Later Cognitive and Behavioural Function

    ERIC Educational Resources Information Center

    Lawson, Katharine R.; Ruff, Holly A.

    2004-01-01

    Negative emotionality and poor attention may combine or interact as risk factors in development. Negative emotionality is considered a challenge for self-regulation, whereas good attention is a potential means of self-regulation. In the current study, composites of 1- and 2-year maternal ratings of negative emotionality and global ratings of…

  10. Eye Direction, Not Movement Direction, Predicts Attention Shifts in Those with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Rutherford, M. D.; Krysko, Kristen M.

    2008-01-01

    Experiments suggesting that a change in eye gaze creates a reflexive attention shift tend to confound motion direction and terminal eye direction. However, motion and the onset of motion are known to capture attention. Current thinking about social cognition in autism suggests that there might be a deficit in responding to social (eye gaze) cues…

  11. Frontolimbic Neural Circuitry at 6 Months Predicts Individual Differences in Joint Attention at 9 Months

    ERIC Educational Resources Information Center

    Elison, Jed T.; Wolff, Jason J.; Heimer, Debra C.; Paterson, Sarah J.; Gu, Hongbin; Hazlett, Heather C.; Styner, Martin; Gerig, Guido; Piven, Joseph

    2013-01-01

    Elucidating the neural basis of joint attention in infancy promises to yield important insights into the development of language and social cognition, and directly informs developmental models of autism. We describe a new method for evaluating responding to joint attention performance in infancy that highlights the 9- to 10-month period as a time…

  12. Emotion Regulation Predicts Attention Bias in Maltreated Children At-Risk for Depression

    ERIC Educational Resources Information Center

    Romens, Sarah E.; Pollak, Seth D.

    2012-01-01

    Background: Child maltreatment is associated with heightened risk for depression; however, not all individuals who experience maltreatment develop depression. Previous research indicates that maltreatment contributes to an attention bias for emotional cues, and that depressed individuals show attention bias for sad cues. Method: The present study…

  13. The Prelimbic Cortex Directs Attention toward Predictive Cues during Fear Learning

    ERIC Educational Resources Information Center

    Sharpe, Melissa J.; Killcross, Simon

    2015-01-01

    The prelimbic cortex is argued to promote conditioned fear expression, at odds with appetitive research implicating this region in attentional processing. Consistent with an attentional account, we report that the effect of prelimbic lesions on fear expression depends on the degree of competition between contextual and discrete cues. Further, when…

  14. Resting EEG in Alpha and Beta Bands Predicts Individual Differences in Attentional Blink Magnitude

    ERIC Educational Resources Information Center

    MacLean, Mary H.; Arnell, Karen M.; Cote, Kimberly A.

    2012-01-01

    Accuracy for a second target (T2) is reduced when it is presented within 500 ms of a first target (T1) in a rapid serial visual presentation (RSVP)--an attentional blink (AB). There are reliable individual differences in the magnitude of the AB. Recent evidence has shown that the attentional approach that an individual typically adopts during a…

  15. Attentional sensitization of unconscious cognition: task sets modulate subsequent masked semantic priming.

    PubMed

    Kiefer, Markus; Martens, Ulla

    2010-08-01

    According to classical theories, automatic processes are autonomous and independent of higher level cognitive influence. In contrast, the authors propose that automatic processing depends on attentional sensitization of task-congruent processing pathways. In 3 experiments, the authors tested this hypothesis with a modified masked semantic priming paradigm during a lexical decision task by measuring event-related potentials (ERPs): Before masked prime presentation, participants attended an induction task either to semantic or perceptual stimulus features designed to activate a semantic or perceptual task set, respectively. Semantic priming effects on the N400 ERP component, an electrophysiological index of semantic processing, were obtained when a semantic task set was induced immediately before subliminal prime presentation, whereas a previously induced perceptual task set attenuated N400 priming. Across experiments, comparable results were obtained regardless of the difficulty level and the verbal or nonverbal nature of the induction tasks. In line with the proposed attentional sensitization model, unconscious semantic processing is enhanced by a semantic and attenuated by a perceptual task set. Hence, automatic processing of unconscious stimuli is susceptible to top-down control for optimizing goal-related information processing. PMID:20677895

  16. Bilingualism modulates infants' selective attention to the mouth of a talking face.

    PubMed

    Pons, Ferran; Bosch, Laura; Lewkowicz, David J

    2015-04-01

    Infants growing up in bilingual environments succeed at learning two languages. What adaptive processes enable them to master the more complex nature of bilingual input? One possibility is that bilingual infants take greater advantage of the redundancy of the audiovisual speech that they usually experience during social interactions. Thus, we investigated whether bilingual infants' need to keep languages apart increases their attention to the mouth as a source of redundant and reliable speech cues. We measured selective attention to talking faces in 4-, 8-, and 12-month-old Catalan and Spanish monolingual and bilingual infants. Monolinguals looked more at the eyes than the mouth at 4 months and more at the mouth than the eyes at 8 months in response to both native and nonnative speech, but they looked more at the mouth than the eyes at 12 months only in response to nonnative speech. In contrast, bilinguals looked equally at the eyes and mouth at 4 months, more at the mouth than the eyes at 8 months, and more at the mouth than the eyes at 12 months, and these patterns of responses were found for both native and nonnative speech at all ages. Thus, to support their dual-language acquisition processes, bilingual infants exploit the greater perceptual salience of redundant audiovisual speech cues at an earlier age and for a longer time than monolingual infants.

  17. Selective attention modulates the effect of target location probability on redundant signal processing.

    PubMed

    Chang, Ting-Yun; Little, Daniel R; Yang, Cheng-Ta

    2016-08-01

    We investigated the decision process underlying the detection of targets at multiple locations. In three experiments using the same observers, target location probability and attentional instructions were manipulated. A redundant-target detection task was conducted in which participants were required to detect a dot presented at one of two locations. When the dot appeared at the two locations with equal frequency (Experiment 1), those participants who were found to have limited to unlimited capacity were shown to adopt a parallel, self-terminating strategy. By contrast, those participants who had supercapacity were shown to process redundant targets in a coactive manner. When targets were presented with unequal probability, two participants adopted a parallel, self-terminating strategy regardless of whether they were informed the target location probability (Experiment 3) or not (Experiment 2). For the remaining two participants, the strategy changed from parallel, self-terminating to serial, self-terminating as a result of the probability instructions. In Experiments 2 and 3, all the participants were of unlimited to limited capacity. Taken together, these results suggest that target location probability differently affects the selection of a decision strategy and highlight the role of controlled attention in selecting a decision strategy.

  18. Bilingualism modulates infants' selective attention to the mouth of a talking face.

    PubMed

    Pons, Ferran; Bosch, Laura; Lewkowicz, David J

    2015-04-01

    Infants growing up in bilingual environments succeed at learning two languages. What adaptive processes enable them to master the more complex nature of bilingual input? One possibility is that bilingual infants take greater advantage of the redundancy of the audiovisual speech that they usually experience during social interactions. Thus, we investigated whether bilingual infants' need to keep languages apart increases their attention to the mouth as a source of redundant and reliable speech cues. We measured selective attention to talking faces in 4-, 8-, and 12-month-old Catalan and Spanish monolingual and bilingual infants. Monolinguals looked more at the eyes than the mouth at 4 months and more at the mouth than the eyes at 8 months in response to both native and nonnative speech, but they looked more at the mouth than the eyes at 12 months only in response to nonnative speech. In contrast, bilinguals looked equally at the eyes and mouth at 4 months, more at the mouth than the eyes at 8 months, and more at the mouth than the eyes at 12 months, and these patterns of responses were found for both native and nonnative speech at all ages. Thus, to support their dual-language acquisition processes, bilingual infants exploit the greater perceptual salience of redundant audiovisual speech cues at an earlier age and for a longer time than monolingual infants. PMID:25767208

  19. Model-Free Estimation of Tuning Curves and Their Attentional Modulation, Based on Sparse and Noisy Data.

    PubMed

    Helmer, Markus; Kozyrev, Vladislav; Stephan, Valeska; Treue, Stefan; Geisel, Theo; Battaglia, Demian

    2016-01-01

    Tuning curves are the functions that relate the responses of sensory neurons to various values within one continuous stimulus dimension (such as the orientation of a bar in the visual domain or the frequency of a tone in the auditory domain). They are commonly determined by fitting a model e.g. a Gaussian or other bell-shaped curves to the measured responses to a small subset of discrete stimuli in the relevant dimension. However, as neuronal responses are irregular and experimental measurements noisy, it is often difficult to determine reliably the appropriate model from the data. We illustrate this general problem by fitting diverse models to representative recordings from area MT in rhesus monkey visual cortex during multiple attentional tasks involving complex composite stimuli. We find that all models can be well-fitted, that the best model generally varies between neurons and that statistical comparisons between neuronal responses across different experimental conditions are affected quantitatively and qualitatively by specific model choices. As a robust alternative to an often arbitrary model selection, we introduce a model-free approach, in which features of interest are extracted directly from the measured response data without the need of fitting any model. In our attentional datasets, we demonstrate that data-driven methods provide descriptions of tuning curve features such as preferred stimulus direction or attentional gain modulations which are in agreement with fit-based approaches when a good fit exists. Furthermore, these methods naturally extend to the frequent cases of uncertain model selection. We show that model-free approaches can identify attentional modulation patterns, such as general alterations of the irregular shape of tuning curves, which cannot be captured by fitting stereotyped conventional models. Finally, by comparing datasets across different conditions, we demonstrate effects of attention that are cell- and even stimulus

  20. Model-Free Estimation of Tuning Curves and Their Attentional Modulation, Based on Sparse and Noisy Data

    PubMed Central

    Helmer, Markus; Kozyrev, Vladislav; Stephan, Valeska; Treue, Stefan; Geisel, Theo; Battaglia, Demian

    2016-01-01

    Tuning curves are the functions that relate the responses of sensory neurons to various values within one continuous stimulus dimension (such as the orientation of a bar in the visual domain or the frequency of a tone in the auditory domain). They are commonly determined by fitting a model e.g. a Gaussian or other bell-shaped curves to the measured responses to a small subset of discrete stimuli in the relevant dimension. However, as neuronal responses are irregular and experimental measurements noisy, it is often difficult to determine reliably the appropriate model from the data. We illustrate this general problem by fitting diverse models to representative recordings from area MT in rhesus monkey visual cortex during multiple attentional tasks involving complex composite stimuli. We find that all models can be well-fitted, that the best model generally varies between neurons and that statistical comparisons between neuronal responses across different experimental conditions are affected quantitatively and qualitatively by specific model choices. As a robust alternative to an often arbitrary model selection, we introduce a model-free approach, in which features of interest are extracted directly from the measured response data without the need of fitting any model. In our attentional datasets, we demonstrate that data-driven methods provide descriptions of tuning curve features such as preferred stimulus direction or attentional gain modulations which are in agreement with fit-based approaches when a good fit exists. Furthermore, these methods naturally extend to the frequent cases of uncertain model selection. We show that model-free approaches can identify attentional modulation patterns, such as general alterations of the irregular shape of tuning curves, which cannot be captured by fitting stereotyped conventional models. Finally, by comparing datasets across different conditions, we demonstrate effects of attention that are cell- and even stimulus

  1. Variation in key genes of serotonin and norepinephrine function predicts gamma-band activity during goal-directed attention.

    PubMed

    Enge, Sören; Fleischhauer, Monika; Lesch, Klaus-Peter; Reif, Andreas; Strobel, Alexander

    2014-05-01

    Recent evidence shows that genetic variations in key regulators of serotonergic (5-HT) signaling explain variance in executive tasks, which suggests modulatory actions of 5-HT on goal-directed selective attention as one possible underlying mechanism. To investigate this link, 130 volunteers were genotyped for the 5-HT transporter gene-linked polymorphic region (5-HTTLPR) and for a variation (TPH2-703 G/T) of the TPH2 gene coding for the rate-limiting enzyme of 5-HT synthesis in the brain. Additionally, a functional polymorphism of the norepinephrine transporter gene (NET -3081 A/T) was considered, which was recently found to predict attention and working memory processes in interaction with serotonergic genes. The flanker-based Attention Network Test was used to assess goal-directed attention and the efficiency of attentional networks. Event-related gamma-band activity served to indicate selective attention at the intermediate phenotype level. The main findings were that 5-HTTLPR s allele and TPH2 G-allele homozygotes showed increased induced gamma-band activity during target processing when combined with the NET A/A genotype compared with other genotype combinations, and that gamma activity mediates the genotype-specific effects on task performance. The results further support a modulatory role of 5-HT and NE function in the top-down attentional selection of motivationally relevant over competing or irrelevant sensory input.

  2. Response control networks are selectively modulated by attention to rare events and memory load regardless of the need for inhibition.

    PubMed

    Wijeakumar, Sobanawartiny; Magnotta, Vincent A; Buss, Aaron T; Ambrose, Joseph P; Wifall, Timothy A; Hazeltine, Eliot; Spencer, John P

    2015-10-15

    Recent evidence has sparked debate about the neural bases of response selection and inhibition. In the current study, we employed two reactive inhibition tasks, the Go/Nogo (GnG) and Simon tasks, to examine questions central to these debates. First, we investigated whether a fronto-cortical-striatal system was sensitive to the need for inhibition per se or the presentation of infrequent stimuli, by manipulating the proportion of trials that do not require inhibition (Go/Compatible trials) relative to trials that require inhibition (Nogo/Incompatible trials). A cortico-subcortical network composed of insula, putamen, and thalamus showed greater activation on salient and infrequent events, regardless of the need for inhibition. Thus, consistent with recent findings, key parts of the fronto-cortical-striatal system are engaged by salient events and do not appear to play a selective role in response inhibition. Second, we examined how the fronto-cortical-striatal system is modulated by working memory demands by varying the number of stimulus-response (SR) mappings. Right inferior parietal lobule showed decreasing activation as the number of SR mappings increased, suggesting that a form of associative memory - rather than working memory - might underlie performance in these tasks. A broad motor planning and control network showed similar trends that were also modulated by the number of motor responses required in each task. Finally, bilateral lingual gyri were more robustly engaged in the Simon task, consistent with the role of this area in shifts of visuo-spatial attention. The current study sheds light on how the fronto-cortical-striatal network is selectively engaged in reactive control tasks and how control is modulated by manipulations of attention and memory load. PMID:26190403

  3. Response control networks are selectively modulated by attention to rare events and memory load regardless of the need for inhibition.

    PubMed

    Wijeakumar, Sobanawartiny; Magnotta, Vincent A; Buss, Aaron T; Ambrose, Joseph P; Wifall, Timothy A; Hazeltine, Eliot; Spencer, John P

    2015-10-15

    Recent evidence has sparked debate about the neural bases of response selection and inhibition. In the current study, we employed two reactive inhibition tasks, the Go/Nogo (GnG) and Simon tasks, to examine questions central to these debates. First, we investigated whether a fronto-cortical-striatal system was sensitive to the need for inhibition per se or the presentation of infrequent stimuli, by manipulating the proportion of trials that do not require inhibition (Go/Compatible trials) relative to trials that require inhibition (Nogo/Incompatible trials). A cortico-subcortical network composed of insula, putamen, and thalamus showed greater activation on salient and infrequent events, regardless of the need for inhibition. Thus, consistent with recent findings, key parts of the fronto-cortical-striatal system are engaged by salient events and do not appear to play a selective role in response inhibition. Second, we examined how the fronto-cortical-striatal system is modulated by working memory demands by varying the number of stimulus-response (SR) mappings. Right inferior parietal lobule showed decreasing activation as the number of SR mappings increased, suggesting that a form of associative memory - rather than working memory - might underlie performance in these tasks. A broad motor planning and control network showed similar trends that were also modulated by the number of motor responses required in each task. Finally, bilateral lingual gyri were more robustly engaged in the Simon task, consistent with the role of this area in shifts of visuo-spatial attention. The current study sheds light on how the fronto-cortical-striatal network is selectively engaged in reactive control tasks and how control is modulated by manipulations of attention and memory load.

  4. Attentional disengagement is modulated by the offset of unpleasant pictures: a saccadic reaction time study.

    PubMed

    Machado-Pinheiro, Walter; Faria, Aydamari; Braga, Filipe; Guerra, Pedro; Perakakis, Pandelis; Caldas, Ariane Leão; Mocaiber, Izabela; Oliveira, Letícia; Pereira, Mirtes Garcia; Volchan, Eliane; Vila, Jaime

    2013-12-01

    We studied the influence of passively viewing a picture on saccade latencies to peripheral targets. Thirty-two volunteers were instructed to look at a central picture, wait for the onset of a peripheral target, and execute a saccade toward it as quickly as possible - saccadic reaction time (SRT). The central picture (neutral or unpleasant) could be turned off simultaneously with target onset (the no-gap condition) or 200ms prior to target onset (the gap-200 condition). We found that saccade latencies were influenced by emotional valence and condition. In the no-gap condition, SRTs were longer after viewing unpleasant pictures. In the gap-200 condition, the pattern was reversed, and unpleasant pictures induced shorter SRTs in relation to neutral pictures. Furthermore, the influence of unpleasant pictures gradually decreased when images were re-exposed to the participants - affective habituation. The results are discussed in terms of attentional avoidance and disengagement from unpleasant emotional pictures. PMID:24177247

  5. Modulation of neural responses to speech by directing attention to voices or verbal content.

    PubMed

    von Kriegstein, Katharina; Eger, Evelyn; Kleinschmidt, Andreas; Giraud, Anne Lise

    2003-06-01

    We studied with functional neuroimaging the cortical response to auditory sentences, comparing two recognition tasks that either targeted the speaker's voice or the verbal content. The right anterior superior temporal sulcus responded during the voice but not during the verbal content task. This response was therefore specifically related to the analysis of nonverbal features of speech. However, the dissociation between verbal and nonverbal analysis was only partial. Left middle temporal regions previously implicated in semantic processing responded in both tasks. This indicates that implicit semantic processing occurred even when the task directed attention to nonverbal input analysis. The verbal task yielded greater bilateral activation in the fusiform/lingual region, presumably reflecting an implicit translation of auditory sentences into visual representations. This result confirms the participation of visual cortical regions in verbal analysis of speech. PMID:12763191

  6. Attention Modulates the Auditory Cortical Processing of Spatial and Category Cues in Naturalistic Auditory Scenes

    PubMed Central

    Renvall, Hanna; Staeren, Noël; Barz, Claudia S.; Ley, Anke; Formisano, Elia

    2016-01-01

    This combined fMRI and MEG study investigated brain activations during listening and attending to natural auditory scenes. We first recorded, using in-ear microphones, vocal non-speech sounds, and environmental sounds that were mixed to construct auditory scenes containing two concurrent sound streams. During the brain measurements, subjects attended to one of the streams while spatial acoustic information of the scene was either preserved (stereophonic sounds) or removed (monophonic sounds). Compared to monophonic sounds, stereophonic sounds evoked larger blood-oxygenation-level-dependent (BOLD) fMRI responses in the bilateral posterior superior temporal areas, independent of which stimulus attribute the subject was attending to. This finding is consistent with the functional role of these regions in the (automatic) processing of auditory spatial cues. Additionally, significant differences in the cortical activation patterns depending on the target of attention were observed. Bilateral planum temporale and inferior frontal gyrus were preferentially activated when attending to stereophonic environmental sounds, whereas when subjects attended to stereophonic voice sounds, the BOLD responses were larger at the bilateral middle superior temporal gyrus and sulcus, previously reported to show voice sensitivity. In contrast, the time-resolved MEG responses were stronger for mono- than stereophonic sounds in the bilateral auditory cortices at ~360 ms after the stimulus onset when attending to the voice excerpts within the combined sounds. The observed effects suggest that during the segregation of auditory objects from the auditory background, spatial sound cues together with other relevant temporal and spectral cues are processed in an attention-dependent manner at the cortical locations generally involved in sound recognition. More synchronous neuronal activation during monophonic than stereophonic sound processing, as well as (local) neuronal inhibitory mechanisms in

  7. Analysis of cardiac autonomic modulation of children with attention deficit hyperactivity disorder

    PubMed Central

    de Carvalho, Tatiana Dias; Wajnsztejn, Rubens; de Abreu, Luiz Carlos; Marques Vanderlei, Luiz Carlos; Godoy, Moacir Fernandes; Adami, Fernando; Valenti, Vitor E; Monteiro, Carlos B M; Leone, Claudio; da Cruz Martins, Karen Cristina; Ferreira, Celso

    2014-01-01

    Background Attention deficit hyperactivity disorder (ADHD) is characterized by decreased attention span, impulsiveness, and hyperactivity. Autonomic nervous system imbalance was previously described in this population. We aim to compare the autonomic function of children with ADHD and controls by analyzing heart rate variability (HRV). Methods Children rested in supine position with spontaneous breathing for 20 minutes. Heart rate was recorded beat by beat. HRV analysis was performed in the time and frequency domains and Poincaré plot. Results Twenty-eight children with ADHD (22 boys, aged 9.964 years) and 28 controls (15 boys, age 9.857 years) participated in this study. It was determined that the mean and standard deviation of indexes which indicate parasympathetic activity is higher in children with ADHD than in children without the disorder: high frequency in normalized units, 46.182 (14.159) versus 40.632 (12.247); root mean square of successive differences, 41.821 (17.834) versus 38.150 (18.357); differences between adjacent normal-to-normal intervals greater than 50 milliseconds, 199.75 (144.00) versus 127.46 (102.21) (P<0.05); percentage of differences between adjacent normal-to-normal intervals greater than 50 milliseconds, 23.957 (17.316) versus 16.211 (13.215); standard deviation of instantaneous beat-to-beat interval, 29.586 (12.622) versus 26.989 (12.983). Conclusion Comparison of the autonomic function by analyzing HRV suggests an increase in the activity of the parasympathetic autonomic nervous systems in children with ADHD in relation to the control group. PMID:24748797

  8. Individual differences in selective attention predict speech identification at a cocktail party.

    PubMed

    Oberfeld, Daniel; Klöckner-Nowotny, Felicitas

    2016-01-01

    Listeners with normal hearing show considerable individual differences in speech understanding when competing speakers are present, as in a crowded restaurant. Here, we show that one source of this variance are individual differences in the ability to focus selective attention on a target stimulus in the presence of distractors. In 50 young normal-hearing listeners, the performance in tasks measuring auditory and visual selective attention was associated with sentence identification in the presence of spatially separated competing speakers. Together, the measures of selective attention explained a similar proportion of variance as the binaural sensitivity for the acoustic temporal fine structure. Working memory span, age, and audiometric thresholds showed no significant association with speech understanding. These results suggest that a reduced ability to focus attention on a target is one reason why some listeners with normal hearing sensitivity have difficulty communicating in situations with background noise. PMID:27580272

  9. Subclinical alexithymia modulates early audio-visual perceptive and attentional event-related potentials

    PubMed Central

    Delle-Vigne, Dyna; Kornreich, Charles; Verbanck, Paul; Campanella, Salvatore

    2014-01-01

    Introduction: Previous studies have highlighted the advantage of using audio–visual oddball tasks (instead of unimodal ones) in order to electrophysiologically index subclinical behavioral differences. Since alexithymia is highly prevalent in the general population, we investigated whether the use of various bimodal tasks could elicit emotional effects in low- vs. high-alexithymic scorers. Methods: Fifty students (33 females and 17 males) were split into groups based on low and high scores on the Toronto Alexithymia Scale (TAS-20). During event-related potential (ERP) recordings, they were exposed to three kinds of audio–visual oddball tasks: neutral-AVN—(geometrical forms and bips), animal-AVA—(dog and cock with their respective shouts), or emotional-AVE—(faces and voices) stimuli. In each condition, participants were asked to quickly detect deviant events occurring amongst a train of repeated and frequent matching stimuli (e.g., push a button when a sad face–voice pair appeared amongst a train of neutral face–voice pairs). P100, N100, and P300 components were analyzed: P100 refers to visual perceptive and attentional processing, N100 to auditory ones, and the P300 relates to response-related stages, involving memory processes. Results: High-alexithymic scorers presented a particular pattern of results when processing the emotional stimulations, reflected in early ERP components by increased P100 and N100 amplitudes in the emotional oddball tasks [P100: F(2, 48) = 20,319, p < 0.001; N100: F(2, 96) = 8,807, p = 0.001] as compared to the animal or neutral ones. Indeed, regarding the P100, subjects exhibited a higher amplitude in the AVE condition (8.717 μV), which was significantly different from that observed during the AVN condition (4.382 μV, p < 0.001). For the N100, the highest amplitude was found in the AVE condition (−4.035 μV) and the lowest was observed in the AVN condition (−2.687 μV, p = 0.003). However, no effect was found on the

  10. Electrophysiological measures of attention during speech perception predict metalinguistic skills in children.

    PubMed

    Astheimer, Lori; Janus, Monika; Moreno, Sylvain; Bialystok, Ellen

    2014-01-01

    Event-related potential (ERP) evidence demonstrates that preschool-aged children selectively attend to informative moments such as word onsets during speech perception. Although this observation indicates a role for attention in language processing, it is unclear whether this type of attention is part of basic speech perception mechanisms, higher-level language skills, or general cognitive abilities. The current study examined these possibilities by measuring ERPs from 5-year-old children listening to a narrative containing attention probes presented before, during, and after word onsets as well as at random control times. Children also completed behavioral tests assessing verbal and nonverbal skills. Probes presented after word onsets elicited a more negative ERP response beginning around 100 ms after probe onset than control probes, indicating increased attention to word-initial segments. Crucially, the magnitude of this difference was correlated with performance on verbal tasks, but showed no relationship to nonverbal measures. More specifically, ERP attention effects were most strongly correlated with performance on a complex metalinguistic task involving grammaticality judgments. These results demonstrate that effective allocation of attention during speech perception supports higher-level, controlled language processing in children by allowing them to focus on relevant information at individual word and complex sentence levels.

  11. Spontaneous Facial Mimicry is Modulated by Joint Attention and Autistic Traits

    PubMed Central

    Neufeld, Janina; Ioannou, Christina; Korb, Sebastian; Schilbach, Leonhard

    2015-01-01

    Joint attention (JA) and spontaneous facial mimicry (SFM) are fundamental processes in social interactions, and they are closely related to empathic abilities. When tested independently, both of these processes have been usually observed to be atypical in individuals with autism spectrum conditions (ASC). However, it is not known how these processes interact with each other in relation to autistic traits. This study addresses this question by testing the impact of JA on SFM of happy faces using a truly interactive paradigm. Sixty‐two neurotypical participants engaged in gaze‐based social interaction with an anthropomorphic, gaze‐contingent virtual agent. The agent either established JA by initiating eye contact or looked away, before looking at an object and expressing happiness or disgust. Eye tracking was used to make the agent's gaze behavior and facial actions contingent to the participants' gaze. SFM of happy expressions was measured by Electromyography (EMG) recording over the Zygomaticus Major muscle. Results showed that JA augments SFM in individuals with low compared with high autistic traits. These findings are in line with reports of reduced impact of JA on action imitation in individuals with ASC. Moreover, they suggest that investigating atypical interactions between empathic processes, instead of testing these processes individually, might be crucial to understanding the nature of social deficits in autism. Autism Res 2016, 9: 781–789. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research PMID:26442665

  12. Spontaneous Facial Mimicry is Modulated by Joint Attention and Autistic Traits.

    PubMed

    Neufeld, Janina; Ioannou, Christina; Korb, Sebastian; Schilbach, Leonhard; Chakrabarti, Bhismadev

    2016-07-01

    Joint attention (JA) and spontaneous facial mimicry (SFM) are fundamental processes in social interactions, and they are closely related to empathic abilities. When tested independently, both of these processes have been usually observed to be atypical in individuals with autism spectrum conditions (ASC). However, it is not known how these processes interact with each other in relation to autistic traits. This study addresses this question by testing the impact of JA on SFM of happy faces using a truly interactive paradigm. Sixty-two neurotypical participants engaged in gaze-based social interaction with an anthropomorphic, gaze-contingent virtual agent. The agent either established JA by initiating eye contact or looked away, before looking at an object and expressing happiness or disgust. Eye tracking was used to make the agent's gaze behavior and facial actions contingent to the participants' gaze. SFM of happy expressions was measured by Electromyography (EMG) recording over the Zygomaticus Major muscle. Results showed that JA augments SFM in individuals with low compared with high autistic traits. These findings are in line with reports of reduced impact of JA on action imitation in individuals with ASC. Moreover, they suggest that investigating atypical interactions between empathic processes, instead of testing these processes individually, might be crucial to understanding the nature of social deficits in autism. Autism Res 2016, 9: 781-789. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research.

  13. The neural correlates of competition during memory retrieval are modulated by attention to the cues

    PubMed Central

    Danker, Jared F.; Fincham, Jon M.; Anderson, John R.

    2011-01-01

    As people learn more facts about a concept, those facts become more difficult to remember. This is called the fan effect, where fan refers to the number of facts known about a concept. Increasing fan has been shown to decrease accuracy and increase response time and left ventrolateral prefrontal cortex (VLPFC) activity during retrieval. In this study, participants learned 36 arbitrary person-location pairings and had to recognize them while we recorded brain activity using fMRI. We separately manipulated the fan of each person and location, as well as the training procedure with which each pair was studied. In the person focus condition, participants studied pairs with a picture of the person’s face and used the person as a retrieval cue during training. In the location focus condition, participants studied pairs with a picture of the location and used the location as a retrieval cue during training. We found that the fan of the focused cue had a greater effect on response time, accuracy, and left VLPFC activity during retrieval than the fan of the unfocused cue. We also found that the parahippocampal place area (PPA) was more active during the recognition of pairs studied in the location focus condition, but not when the fan of the location was high. Overall, we found opposite effects of fan on VLPFC and PPA that were modulated by cue focus. PMID:21549721

  14. The neural correlates of competition during memory retrieval are modulated by attention to the cues.

    PubMed

    Danker, Jared F; Fincham, Jon M; Anderson, John R

    2011-07-01

    As people learn more facts about a concept, those facts become more difficult to remember. This is called the fan effect, where fan refers to the number of facts known about a concept. Increasing fan has been shown to decrease accuracy and increase response time and left ventrolateral prefrontal cortex (VLPFC) activity during retrieval. In this study, participants learned 36 arbitrary person-location pairings and made recognition decisions while we recorded brain activity using fMRI. We separately manipulated the fan of each person and location, as well as the training procedure with which each pair was studied. In the person focus condition, participants studied pairs with a picture of the person's face and used the person as a retrieval cue during training. In the location focus condition, participants studied pairs with a picture of the location and used the location as a retrieval cue during training. We found that the fan of the focused cue had a greater effect on response time, accuracy, and left VLPFC activity during retrieval than the fan of the unfocused cue. We also found that the parahippocampal place area (PPA) was more active during the recognition of pairs studied in the location focus condition, but not when the fan of the location was high. Overall, we found opposite effects of fan on VLPFC and PPA that were modulated by cue focus. PMID:21549721

  15. Spectrum sensitivity, energy yield, and revenue prediction of PV and CPV modules

    NASA Astrophysics Data System (ADS)

    Kinsey, Geoffrey S.

    2015-09-01

    Impact on module performance of spectral irradiance variation has been determined for III-V multijunctions compared against the four most common flat-plate module types (cadmium telluride, multicrystalline silicon, copper indium gallium selenide, and monocrystalline silicon. Hour-by-hour representative spectra were generated using atmospheric variables for Albuquerque, New Mexico, USA. Convolution with published values for external quantum efficiency gave the predicted current output. When combined with specifications of commercial PV modules, energy yield and revenue were predicted. This approach provides a means for optimizing PV module design based on various site-specific temporal variables.

  16. Spectrum sensitivity, energy yield, and revenue prediction of PV and CPV modules

    SciTech Connect

    Kinsey, Geoffrey S.

    2015-09-28

    Impact on module performance of spectral irradiance variation has been determined for III-V multijunctions compared against the four most common flat-plate module types (cadmium telluride, multicrystalline silicon, copper indium gallium selenide, and monocrystalline silicon. Hour-by-hour representative spectra were generated using atmospheric variables for Albuquerque, New Mexico, USA. Convolution with published values for external quantum efficiency gave the predicted current output. When combined with specifications of commercial PV modules, energy yield and revenue were predicted. This approach provides a means for optimizing PV module design based on various site-specific temporal variables.

  17. Character Decomposition and Transposition Processes in Chinese Compound Words Modulates Attentional Blink

    PubMed Central

    Cao, Hongwen; Gao, Min; Yan, Hongmei

    2016-01-01

    The attentional blink (AB) is the phenomenon in which the identification of the second of two targets (T2) is attenuated if it is presented less than 500 ms after the first target (T1). Although the AB is eliminated in canonical word conditions, it remains unclear whether the character order in compound words affects the magnitude of the AB. Morpheme decomposition and transposition of Chinese two-character compound words can provide an effective means to examine AB priming and to assess combinations of the component representations inherent to visual word identification. In the present study, we examined the processing of consecutive targets in a rapid serial visual presentation (RSVP) paradigm using Chinese two-character compound words in which the two characters were transposed to form meaningful words or meaningless combinations (reversible, transposed, or canonical words). We found that when two Chinese characters that form a compound word, regardless of their order, are presented in an RSVP sequence, the likelihood of an AB for the second character is greatly reduced or eliminated compared to when the two characters constitute separate words rather than a compound word. Moreover, the order of the report for the two characters is more likely to be reversed when the normal order of the two characters in a compound word is reversed, especially when the interval between the presentation of the two characters is extremely short. These findings are more consistent with the cognitive strategy hypothesis than the resource-limited hypothesis during character decomposition and transposition of Chinese two-character compound words. These results suggest that compound characters are perceived as a unit, rather than two separate words. The data further suggest that readers could easily understand the text with character transpositions in compound words during Chinese reading. PMID:27379003

  18. Religion and the Attentional Blink: Depth of Faith Predicts Depth of the Blink

    PubMed Central

    Colzato, Lorenza S.; Hommel, Bernhard; Shapiro, Kimron L.

    2010-01-01

    Religion is commonly defined as a set of rules, developed as part of a culture. Here we provide evidence that practice in following these rules systematically changes the way people allocate their attention, as indicated by the attentional blink (AB), a deficit in reporting the second of two target stimuli presented in close succession in a rapid sequence of distracters. We provide evidence that Dutch Calvinists and Atheists, brought up in the same country and culture and controlled for race, intelligence, mood, personality traits, and age, differ with respect to the amount of resources invested into processing AB targets. Calvinists showed a larger AB than Atheists, which is consistent with the notion that people's attentional processing style reflects biases rewarded by their religious beliefs. PMID:21833216

  19. Attentional control and inferences of agency: Working memory load differentially modulates goal-based and prime-based agency experiences.

    PubMed

    Renes, Robert A; van Haren, Neeltje E M; Aarts, Henk

    2015-12-15

    Previous research indicates that people can infer self-agency, the experience of causing outcomes as a result of one's own actions, in situations where information about action-outcomes is pre-activated through goal-setting or priming. We argue that goal-based agency inferences rely on attentional control that processes information about matches and mismatches between intended and actual outcomes. Prime-based inferences follow an automatic cognitive accessibility process that relies on matches between primed and actual information about outcomes. We tested an improved task for a better examination of goal-based vs. primed-based agency inferences, and examined the moderating effect of working memory load on both types of inferences. Findings of four studies showed that goal-based, but not prime-based agency inferences dwindled under working memory load. These findings suggest that goal-based (vs. primed-based) agency inferences indeed rely on attentional control, thus rendering goal-based agency inferences especially prone to conditions that modulate goal-directed control processes. PMID:26497069

  20. Acute aerobic exercise enhances attentional modulation of somatosensory event-related potentials during a tactile discrimination task.

    PubMed

    Popovich, Christina; Staines, W Richard

    2015-03-15

    Neuroimaging research has shown that acute bouts of moderate intensity aerobic exercise can enhance attention-based neuronal activity in frontal brain regions, namely in the prefrontal cortex (PFC), as well as improve cognitive performance. The circuitry of the PFC is complex with extensive reciprocal corticocortical and thalamocortical connections, yet it remains unclear if aerobic exercise can also assist attentional control over modality-specific sensory cortices. To test this, we used a tactile discrimination task to compare tactile event-related potentials (ERPs) prior to and following an acute bout of moderate intensity aerobic exercise. We hypothesized that exercise preceding performance of the task would result in more efficient sensory gating of irrelevant/non-attended and enhancement of relevant/attended sensory information, respectively. Participants received vibrotactile stimulation to the second and fifth digit on the left hand and reported target stimuli on one digit only. ERP amplitudes for the P50, P100, N140 and long latency positivity (LLP) were quantified for attended and non-attended trials at FC4, C4, CP4 and P4 while P300 amplitudes were quantified in response to attended target stimuli at electrodes FCZ, CZ and CPZ. Results showed no effect of attention on the P50, however, both P100 and LLP amplitudes were significantly greater during attended, task-relevant trials, while the N140 was enhanced for non-attended, task-irrelevant stimuli. Moreover, unattended N140 amplitudes over parietal sites contralateral to stimulation were significantly greater post-exercise versus pre-exercise, while LLP modulation varied with greater unattended amplitudes post-exercise over frontal sites and greater attended amplitudes post-exercise over parietal sites. These results suggest that a single session of moderate intensity aerobic exercise facilitated the sensory gating of task-irrelevant tactile stimuli so that relevant sensory signals could be enhanced at

  1. The Role of Executive Functions in Attention Deficit Hyperactivity Disorder: Testing Predictions from Two Models

    ERIC Educational Resources Information Center

    Lee, Donghyung; Riccio, Cynthia A.; Hynd, George W.

    2004-01-01

    The role of executive functions in attention deficit hyperactivity disorder (ADHD) varies considerably depending on the models of ADHD. We examined the interrelationship of two major executive functions (i.e., inhibition and working memory) with behavioral, emotional, and school problems in a group of children who had a comprehensive…

  2. Does Childhood Attention-Deficit/Hyperactivity Disorder Predict Risk-Taking and Medical Illnesses in Adulthood?

    ERIC Educational Resources Information Center

    Ramos Olazagasti, Maria A.; Klein, Rachel G.; Mannuzza, Salvatore; Belsky, Erica Roizen; Hutchison, Jesse A.; Lashua-Shriftman, Erin C.; Castellanos, F. Xavier

    2013-01-01

    Objective: To test whether children with attention-deficit/hyperactivity disorder (ADHD), free of conduct disorder (CD) in childhood (mean = 8 years), have elevated risk-taking, accidents, and medical illnesses in adulthood (mean = 41 years); whether development of CD influences risk-taking during adulthood; and whether exposure to…

  3. White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Cooper, Miriam; Thapar, Anita; Jones, Derek K.

    2014-01-01

    Traits of autism spectrum disorder (ASD) in children with attention-deficit/hyperactivity disorder (ADHD) have previously been found to index clinical severity. This study examined the association of ASD traits with diffusion parameters in adolescent males with ADHD (n = 17), and also compared WM microstructure relative to controls (n = 17).…

  4. Parental Attention-Deficit/Hyperactivity Disorder Predicts Child and Parent Outcomes of Parental Friendship Coaching Treatment

    ERIC Educational Resources Information Center

    Griggs, Marissa Swaim; Mikami, Amori Yee

    2011-01-01

    Objective: This study investigated the impact of parental attention-deficit/hyperactivity disorder (ADHD) symptoms on the peer relationships and parent-child interaction outcomes of children with ADHD among families completing a randomized controlled trial of parental friendship coaching (PFC) relative to control families. Method: Participants…

  5. Early Childhood Assessments of Community Pediatric Professionals Predict Autism Spectrum and Attention Deficit Hyperactivity Problems

    ERIC Educational Resources Information Center

    Jaspers, Merlijne; de Winter, Andrea F.; Buitelaar, Jan K.; Verhulst, Frank C.; Reijneveld, Sijmen A.; Hartman, Catharina A.

    2013-01-01

    For clinically referred children with Autism Spectrum Disorder (ASD) or Attention Deficit/Hyperactivity Disorder (ADHD) several early indicators have been described. However, knowledge is lacking on early markers of less severe variants of ASD and ADHD from the general population. The aim of the present study is to identify early indicators of…

  6. Gender and Conduct Problems Predict Peer Functioning among Children with Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Mikami, Amori Yee; Lorenzi, Jill

    2011-01-01

    Children with attention-deficit/hyperactivity disorder (ADHD) often have poor relationships with peers. However, research on this topic has predominantly focused on boys. This study considered child gender, ADHD status, and dimensionally assessed conduct problems as predictors of peer relationship difficulties. Participants were 125 children (ages…

  7. The deployment of visual spatial attention during visual search predicts response time: electrophysiological evidence from the N2pc.

    PubMed

    Drisdelle, Brandi L; West, Greg L; Jolicoeur, Pierre

    2016-11-01

    We tracked the deployment of visual spatial attention, as indexed by an electrophysiological event-related potential named the N-2-posterior-contralateral (N2pc). We expected that a stronger and/or earlier deployment of attention would predict faster responses in a visual search task. We tested this hypothesis by sorting the electrophysiological segments into two categories (slow vs. fast) by trial-by-trial response times (RTs), for each participant, on the basis of the median RT within each condition of the experiment. We also classified participants on the basis of overall mean RTs into those faster than the group median and those slower than the group median. The N2pc was larger and earlier for fast responders compared with slow responders. Furthermore, within each of these groups, faster responses were associated with a larger and earlier N2pc. These results provide further evidence that the N2pc is a valid index of the deployment of visual attention, and suggest that a more effective deployment of visual spatial attention (larger and/or earlier N2pc) predicts a faster response, both within and between subjects. PMID:27648715

  8. Executive function and IQ predict mathematical and attention problems in very preterm children.

    PubMed

    Aarnoudse-Moens, Cornelieke Sandrine Hanan; Weisglas-Kuperus, Nynke; Duivenvoorden, Hugo Joseph; van Goudoever, Johannes Bernard; Oosterlaan, Jaap

    2013-01-01

    Objective of this study was to examine the impact of executive function (EF) on mathematical and attention problems in very preterm (gestational age ≤ 30 weeks) children. Participants were 200 very preterm (mean age 8.2 ± 2.5 years) and 230 term children (mean age 8.3 ± 2.3 years) without severe disabilities, born between 1996 and 2004. EFs assessed included verbal fluency, verbal working memory, visuospatial span, planning, and impulse control. Mathematics was assessed with the Dutch Pupil Monitoring System and parents and teachers rated attention problems using standardized behavior questionnaires. The impact of EF was calculated over and above processing speed indices and IQ. Interactions with group (very preterm versus term birth status) were examined. Analyses were conducted separately for two subsamples: children in preschool and children in primary school. Very preterm children performed poorer on tests for mathematics and had more parent and teacher rated attention problems than term controls (ß(s)>.11, P(s)<.01). IQ contributed unique variance to mathematics in preschool and in primary school (ß(s)>.16, P(s)<.007). A significant interaction of group with IQ (ß = -. 24, P = .02) showed that IQ contributed unique variance to attention problems as rated by teachers, but that effects were stronger for very preterm than for term infants. Over and above IQ, EF contributed unique variance to mathematics in primary school (ß = .13, P<.001), to parent rated inattention in preschool and in primary school (ß(s)>-.16, P(s)<.04), and to teacher rated inattention in primary school (ß = -.19; ß = .19, P(s)<.009). In conclusion, impaired EF is, over and above impaired IQ, an important predictor for poor mathematics and attention problems following very preterm birth.

  9. Attentional Selection Can Be Predicted by Reinforcement Learning of Task-relevant Stimulus Features Weighted by Value-independent Stickiness.

    PubMed

    Balcarras, Matthew; Ardid, Salva; Kaping, Daniel; Everling, Stefan; Womelsdorf, Thilo

    2016-02-01

    Attention includes processes that evaluate stimuli relevance, select the most relevant stimulus against less relevant stimuli, and bias choice behavior toward the selected information. It is not clear how these processes interact. Here, we captured these processes in a reinforcement learning framework applied to a feature-based attention task that required macaques to learn and update the value of stimulus features while ignoring nonrelevant sensory features, locations, and action plans. We found that value-based reinforcement learning mechanisms could account for feature-based attentional selection and choice behavior but required a value-independent stickiness selection process to explain selection errors while at asymptotic behavior. By comparing different reinforcement learning schemes, we found that trial-by-trial selections were best predicted by a model that only represents expected values for the task-relevant feature dimension, with nonrelevant stimulus features and action plans having only a marginal influence on covert selections. These findings show that attentional control subprocesses can be described by (1) the reinforcement learning of feature values within a restricted feature space that excludes irrelevant feature dimensions, (2) a stochastic selection process on feature-specific value representations, and (3) value-independent stickiness toward previous feature selections akin to perseveration in the motor domain. We speculate that these three mechanisms are implemented by distinct but interacting brain circuits and that the proposed formal account of feature-based stimulus selection will be important to understand how attentional subprocesses are implemented in primate brain networks.

  10. Using Accelerated Testing To Predict Module Reliability: Preprint

    SciTech Connect

    Wohlgemuth, J. H.; Kurtz, S.

    2011-07-01

    Long-term reliability is critical to the cost effectiveness and commercial success of photovoltaic (PV) products. Today most PV modules are warranted for 25 years, but there is no accepted test protocol to validate a 25-year lifetime. The qualification tests do an excellent job of identifying design, materials, and process flaws that are likely to lead to premature failure (infant mortality), but they are not designed to test for wear-out mechanisms that limit lifetime. This paper presents a method for evaluating the ability of a new PV module technology to survive long-term exposure to specific stresses. The authors propose the use of baseline technologies with proven long-term field performance as controls in the accelerated stress tests. The performance of new-technology modules can then be evaluated versus that of proven-technology modules. If the new-technology demonstrates equivalent or superior performance to the proven one, there is a high likelihood that they will survive versus the tested stress in the real world.

  11. Prediction of pilot reserve attention capacity during air-to-air target tracking

    NASA Technical Reports Server (NTRS)

    Onstott, E. D.; Faulkner, W. H.

    1977-01-01

    Reserve attention capacity of a pilot was calculated using a pilot model that allocates exclusive model attention according to the ranking of task urgency functions whose variables are tracking error and error rate. The modeled task consisted of tracking a maneuvering target aircraft both vertically and horizontally, and when possible, performing a diverting side task which was simulated by the precise positioning of an electrical stylus and modeled as a task of constant urgency in the attention allocation algorithm. The urgency of the single loop vertical task is simply the magnitude of the vertical tracking error, while the multiloop horizontal task requires a nonlinear urgency measure of error and error rate terms. Comparison of model results with flight simulation data verified the computed model statistics of tracking error of both axes, lateral and longitudinal stick amplitude and rate, and side task episodes. Full data for the simulation tracking statistics as well as the explicit equations and structure of the urgency function multiaxis pilot model are presented.

  12. The Role of Strategic Attention Deployment in Development of Self-Regulation: Predicting Preschoolers' Delay of Gratification from Mother-Toddler Interactions.

    ERIC Educational Resources Information Center

    Sethi, Anita; Mischel, Walter; Aber, J. Lawrence; Shoda, Yuichi; Rodriguez, Monica Larrea

    2000-01-01

    Examined role of toddlers' attention deployment strategies in predicting 5-year-olds' delay-of-gratification strategies. Found that toddlers' use of effective attention deployment strategies to cope with separation from mother and with maternal behavior (controlling or noncontrolling) predicted effective delay-of-gratification strategies at age 5,…

  13. Repetitive Transcranial Magnetic Stimulation (rTMS) Modulates Event-Related Potential (ERP) Indices of Attention in Autism

    PubMed Central

    Casanova, Manuel F.; Baruth, Joshua M.; El-Baz, Ayman; Tasman, Allan; Sears, Lonnie; Sokhadze, Estate

    2014-01-01

    Individuals with autism spectrum disorder (ASD) have previously been shown to have significantly augmented and prolonged event-related potentials (ERP) to irrelevant visual stimuli compared to controls at both early and later stages (e.g., N200, P300) of visual processing and evidence of an overall lack of stimulus discrimination. Abnormally large and indiscriminative cortical responses to sensory stimuli may reflect cortical inhibitory deficits and a disruption in the excitation/inhibition ratio. Low-frequency (≤1HZ) repetitive transcranial magnetic stimulation (rTMS) has been shown to increase inhibition of stimulated cortex by the activation of inhibitory circuits. It was our prediction that after 12 sessions of low-frequency rTMS applied bilaterally to the dorsolateral prefrontal cortices in individuals with ASD there would be a significant improvement in ERP indices of selective attention evoked at later (i.e., 200–600 ms) stages of attentional processing as well as an improvement in motor response error rate. We assessed 25 participants with ASD in a task of selective attention using illusory figures before and after 12 sessions of rTMS in a controlled design where a waiting-list group of 20 children with ASD performed the same task twice. We found a significant improvement in both N200 and P300 components as a result of rTMS as well as a significant reduction in response errors. We also found significant reductions in both repetitive behavior and irritability according to clinical behavioral questionnaires as a result of rTMS. We propose that rTMS has the potential to become an important therapeutic tool in ASD research and treatment. PMID:24683490

  14. Hunger modulates behavioral disinhibition and attention allocation to food-associated cues in normal-weight controls.

    PubMed

    Loeber, Sabine; Grosshans, Martin; Herpertz, Stephan; Kiefer, Falk; Herpertz, Sabine C

    2013-12-01

    Overeating, weight gain and obesity are considered as a major health problem in Western societies. At present, an impairment of response inhibition and a biased salience attribution to food-associated stimuli are considered as important factors associated with weight gain. However, recent findings suggest that the association between an impaired response inhibition and salience attribution and weight gain might be modulated by other factors. Thus, hunger might cause food-associated cues to be perceived as more salient and rewarding and might be associated with an impairment of response inhibition. However, at present, little is known how hunger interacts with these processes. Thus, the aim of the present study was to investigate whether hunger modulates response inhibition and attention allocation towards food-associated stimuli in normal-weight controls. A go-/nogo task with food-associated and control words and a visual dot-probe task with food-associated and control pictures were administered to 48 normal-weight participants (mean age 24.5 years, range 19-40; mean BMI 21.6, range 18.5-25.4). Hunger was assessed twofold using a self-reported measure of hunger and a measurement of the blood glucose level. Our results indicated that self-reported hunger affected behavioral response inhibition in the go-/nogo task. Thus, hungry participants committed significantly more commission errors when food-associated stimuli served as distractors compared to when control stimuli were the distractors. This effect was not observed in sated participants. In addition, we found that self-reported hunger was associated with a lower number of omission errors in response to food-associated stimuli indicating a higher salience of these stimuli. Low blood glucose level was not associated with an impairment of response inhibition. However, our results indicated that the blood glucose level was associated with an attentional bias towards food-associated cues in the visual dot probe task

  15. Deficient cardiovascular stress reactivity predicts poor executive functions in adults with attention-deficit/hyperactivity disorder.

    PubMed

    Hirvikoski, Tatja; Olsson, Erik M G; Nordenstrom, Anna; Lindholm, Torun; Nordstrom, Anna-Lena; Lajic, Svetlana

    2011-01-01

    Associations between cardiovascular stress markers, subjective stress reactivity, and executive functions were studied in 60 adults (30 with attention-deficit/hyperactivity disorder, ADHD, and 30 controls) using the Paced Auditory Serial Addition Test (PASAT, a test of executive functions) as a cognitive stressor. Despite higher self-perceived stress, the adults with ADHD showed lower or atypical cardiovascular stress reactivity, which was associated with poorer performance on PASAT. Using cardiovascular stress markers, subjective stress, and results on PASAT as predictors in a logistic regression, 83.3% of the ADHD group and 86.9% of the controls could be classified correctly.

  16. Cross-Language Modulation of Visual Attention Span: An Arabic-French-Spanish Comparison in Skilled Adult Readers.

    PubMed

    Awadh, Faris H R; Phénix, Thierry; Antzaka, Alexia; Lallier, Marie; Carreiras, Manuel; Valdois, Sylviane

    2016-01-01

    In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages -French, Spanish, and Arabic- that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features. PMID:27014125

  17. Cross-Language Modulation of Visual Attention Span: An Arabic-French-Spanish Comparison in Skilled Adult Readers

    PubMed Central

    Awadh, Faris H. R.; Phénix, Thierry; Antzaka, Alexia; Lallier, Marie; Carreiras, Manuel; Valdois, Sylviane

    2016-01-01

    In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages –French, Spanish, and Arabic– that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features. PMID:27014125

  18. Cross-Language Modulation of Visual Attention Span: An Arabic-French-Spanish Comparison in Skilled Adult Readers.

    PubMed

    Awadh, Faris H R; Phénix, Thierry; Antzaka, Alexia; Lallier, Marie; Carreiras, Manuel; Valdois, Sylviane

    2016-01-01

    In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages -French, Spanish, and Arabic- that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features.

  19. Initial sociometric impressions of attention-deficit hyperactivity disorder and comparison boys: predictions from social behaviors and from nonbehavioral variables.

    PubMed

    Erhardt, D; Hinshaw, S P

    1994-08-01

    This study systematically compared the influence of naturalistic social behaviors and nonbehavioral variables on the development of peer status in 49 previously unfamiliar boys, aged 6-12 years, who attended a summer research program. Twenty-five boys with attention-deficit hyperactivity disorder (ADHD) and 24 comparison boys participated. Physical attractiveness, motor competence, intelligence, and academic achievement constituted the nonbehavioral variables; social behaviors included noncompliance, aggression, prosocial actions, and isolation, measured by live observations of classroom and playground interactions. As early as the first day of interaction, ADHD and comparison boys displayed clear differences in social behaviors, and the ADHD youngsters were overwhelmingly rejected. Whereas prosocial behavior independently predicted friendship ratings during the first week, the magnitude of prediction was small. In contrast, the boys' aggression (or noncompliance) strongly predicted negative nominations, even with nonbehavioral factors, group status (ADHD versus comparison), and other social behaviors controlled statistically. Implications for understanding and remediating negative peer reputations are discussed.

  20. Changes in frontal EEG coherence across infancy predict cognitive abilities at age 3: The mediating role of attentional control.

    PubMed

    Whedon, Margaret; Perry, Nicole B; Calkins, Susan D; Bell, Martha Ann

    2016-09-01

    Theoretical perspectives of cognitive development have maintained that functional integration of the prefrontal cortex across infancy underlies the emergence of attentional control and higher cognitive abilities in early childhood. To investigate these proposed relations, we tested whether functional integration of prefrontal regions across the second half of the first year predicted observed cognitive performance in early childhood 1 year prior indirectly through observed attentional control (N = 300). Results indicated that greater change in left-but not right-frontal EEG coherence between 5 and 10 months was positively associated with attentional control, cognitive flexibility, receptive language, and behavioral inhibitory control. Specifically, a larger increase in coherence between left frontal regions was positively associated with accuracy on a visual search task at Age 2, and visual search accuracy was positively associated with receptive vocabulary, performance on a set-shifting task (DCCS), and delay of gratification at Age 3. Finally, the indirect effects from the change in left frontal EEG coherence to 3-year cognitive flexibility, receptive language, and behavioral inhibitory control were significant, suggesting that internally controlled attention is a mechanism through which early neural maturation influences children's cognitive development. (PsycINFO Database Record PMID:27441486

  1. Internal performance predictions for Langley scramjet engine module

    NASA Technical Reports Server (NTRS)

    Pinckney, S. Z.

    1978-01-01

    A one dimensional theoretical method for the prediction of the internal performance of a scramjet engine is presented. The effects of changes in vehicle forebody flow parameters and characteristics on predicted thrust for the scramjet engine were evaluated using this method, and results are presented. A theoretical evaluation of the effects of changes in the scramjet engine's internal parameters is also presented. Theoretical internal performance predictions, in terms thrust coefficient and specific impulse, are provided for the scramjet engine for free stream Mach numbers of 5, 6, and 7 free stream dynamic pressure of 23,940 N/sq m forebody surface angles of 4.6 deg to 14.6 deg, and fuel equivalence ratio of 1.0.

  2. Neurophysiology of Reward-Guided Behavior: Correlates Related to Predictions, Value, Motivation, Errors, Attention, and Action.

    PubMed

    Bissonette, Gregory B; Roesch, Matthew R

    2016-01-01

    Many brain areas are activated by the possibility and receipt of reward. Are all of these brain areas reporting the same information about reward? Or are these signals related to other functions that accompany reward-guided learning and decision-making? Through carefully controlled behavioral studies, it has been shown that reward-related activity can represent reward expectations related to future outcomes, errors in those expectations, motivation, and signals related to goal- and habit-driven behaviors. These dissociations have been accomplished by manipulating the predictability of positively and negatively valued events. Here, we review single neuron recordings in behaving animals that have addressed this issue. We describe data showing that several brain areas, including orbitofrontal cortex, anterior cingulate, and basolateral amygdala signal reward prediction. In addition, anterior cingulate, basolateral amygdala, and dopamine neurons also signal errors in reward prediction, but in different ways. For these areas, we will describe how unexpected manipulations of positive and negative value can dissociate signed from unsigned reward prediction errors. All of these signals feed into striatum to modify signals that motivate behavior in ventral striatum and guide responding via associative encoding in dorsolateral striatum. PMID:26276036

  3. Neurophysiology of Reward-Guided Behavior: Correlates Related to Predictions, Value, Motivation, Errors, Attention, and Action.

    PubMed

    Bissonette, Gregory B; Roesch, Matthew R

    2016-01-01

    Many brain areas are activated by the possibility and receipt of reward. Are all of these brain areas reporting the same information about reward? Or are these signals related to other functions that accompany reward-guided learning and decision-making? Through carefully controlled behavioral studies, it has been shown that reward-related activity can represent reward expectations related to future outcomes, errors in those expectations, motivation, and signals related to goal- and habit-driven behaviors. These dissociations have been accomplished by manipulating the predictability of positively and negatively valued events. Here, we review single neuron recordings in behaving animals that have addressed this issue. We describe data showing that several brain areas, including orbitofrontal cortex, anterior cingulate, and basolateral amygdala signal reward prediction. In addition, anterior cingulate, basolateral amygdala, and dopamine neurons also signal errors in reward prediction, but in different ways. For these areas, we will describe how unexpected manipulations of positive and negative value can dissociate signed from unsigned reward prediction errors. All of these signals feed into striatum to modify signals that motivate behavior in ventral striatum and guide responding via associative encoding in dorsolateral striatum.

  4. The functional tumor necrosis factor-α (308A/G) polymorphism modulates attentional selection in elderly individuals.

    PubMed

    Gajewski, Patrick D; Hengstler, Jan G; Golka, Klaus; Falkenstein, Michael; Beste, Christian

    2013-11-01

    There has been increasing interest in understanding the role of inflammatory processes for cognitive functions in aging using molecular genetic approaches. Though this has mostly been evaluated in pathological aging, little is known about the relevance for cognitive functions in healthy aging in humans. On the basis of behavioral data and neurophysiological data (event-related potentials and time-frequency decomposition) we show that the A-allele of the functional tumor necrosis factor (TNF)-α -308 A/G polymorphism confers dysfunction in a number of cognitive processes: prolonged attentional selection indexed by a delayed P1/N1 complex, an increased P3a, which is interpreted as an enhanced distractibility by nonrelevant stimuli and compromised response selection mechanisms, as indexed by a reduced frontocentral N2. Time-frequency analyses show that allelic variations further exert their effects by modulating alpha and beta frequency oscillations. On a neurobiological level, these effects might be because of the interaction of TNF-α with glutamatergic neural transmission by which TNF-α is known to boost apoptotic mechanisms in elderly individuals.

  5. Idiosyncratic responding during movie-watching predicted by age differences in attentional control.

    PubMed

    Campbell, Karen L; Shafto, Meredith A; Wright, Paul; Tsvetanov, Kamen A; Geerligs, Linda; Cusack, Rhodri; Tyler, Lorraine K

    2015-11-01

    Much is known about how age affects the brain during tightly controlled, though largely contrived, experiments, but do these effects extrapolate to everyday life? Naturalistic stimuli, such as movies, closely mimic the real world and provide a window onto the brain's ability to respond in a timely and measured fashion to complex, everyday events. Young adults respond to these stimuli in a highly synchronized fashion, but it remains to be seen how age affects neural responsiveness during naturalistic viewing. To this end, we scanned a large (N = 218), population-based sample from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) during movie-watching. Intersubject synchronization declined with age, such that older adults' response to the movie was more idiosyncratic. This decreased synchrony related to cognitive measures sensitive to attentional control. Our findings suggest that neural responsivity changes with age, which likely has important implications for real-world event comprehension and memory.

  6. Idiosyncratic responding during movie-watching predicted by age differences in attentional control.

    PubMed

    Campbell, Karen L; Shafto, Meredith A; Wright, Paul; Tsvetanov, Kamen A; Geerligs, Linda; Cusack, Rhodri; Tyler, Lorraine K

    2015-11-01

    Much is known about how age affects the brain during tightly controlled, though largely contrived, experiments, but do these effects extrapolate to everyday life? Naturalistic stimuli, such as movies, closely mimic the real world and provide a window onto the brain's ability to respond in a timely and measured fashion to complex, everyday events. Young adults respond to these stimuli in a highly synchronized fashion, but it remains to be seen how age affects neural responsiveness during naturalistic viewing. To this end, we scanned a large (N = 218), population-based sample from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) during movie-watching. Intersubject synchronization declined with age, such that older adults' response to the movie was more idiosyncratic. This decreased synchrony related to cognitive measures sensitive to attentional control. Our findings suggest that neural responsivity changes with age, which likely has important implications for real-world event comprehension and memory. PMID:26359527

  7. Idiosyncratic responding during movie-watching predicted by age differences in attentional control

    PubMed Central

    Campbell, Karen L.; Shafto, Meredith A.; Wright, Paul; Tsvetanov, Kamen A.; Geerligs, Linda; Cusack, Rhodri; Tyler, Lorraine K.; Brayne, Carol; Bullmore, Ed; Calder, Andrew; Cusack, Rhodri; Dalgleish, Tim; Duncan, John; Henson, Rik; Matthews, Fiona; Marslen-Wilson, William; Rowe, James; Shafto, Meredith; Campbell, Karen; Cheung, Teresa; Davis, Simon; Geerligs, Linda; Kievit, Rogier; McCarrey, Anna; Price, Darren; Taylor, Jason; Tsvetanov, Kamen; Williams, Nitin; Bates, Lauren; Emery, Tina; Erzinçlioglu, Sharon; Gadie, Andrew; Gerbase, Sofia; Georgieva, Stanimira; Hanley, Claire; Parkin, Beth; Troy, David; Allen, Jodie; Amery, Gillian; Amunts, Liana; Barcroft, Anne; Castle, Amanda; Dias, Cheryl; Dowrick, Jonathan; Fair, Melissa; Fisher, Hayley; Goulding, Anna; Grewal, Adarsh; Hale, Geoff; Hilton, Andrew; Johnson, Frances; Johnston, Patricia; Kavanagh-Williamson, Thea; Kwasniewska, Magdalena; McMinn, Alison; Norman, Kim; Penrose, Jessica; Roby, Fiona; Rowland, Diane; Sargeant, John; Squire, Maggie; Stevens, Beth; Stoddart, Aldabra; Stone, Cheryl; Thompson, Tracy; Yazlik, Ozlem; Dixon, Marie; Barnes, Dan; Hillman, Jaya; Mitchell, Joanne; Villis, Laura; Tyler, Lorraine K.

    2015-01-01

    Much is known about how age affects the brain during tightly controlled, though largely contrived, experiments, but do these effects extrapolate to everyday life? Naturalistic stimuli, such as movies, closely mimic the real world and provide a window onto the brain's ability to respond in a timely and measured fashion to complex, everyday events. Young adults respond to these stimuli in a highly synchronized fashion, but it remains to be seen how age affects neural responsiveness during naturalistic viewing. To this end, we scanned a large (N = 218), population-based sample from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) during movie-watching. Intersubject synchronization declined with age, such that older adults' response to the movie was more idiosyncratic. This decreased synchrony related to cognitive measures sensitive to attentional control. Our findings suggest that neural responsivity changes with age, which likely has important implications for real-world event comprehension and memory. PMID:26359527

  8. Working memory capacity and visual-verbal cognitive load modulate auditory-sensory gating in the brainstem: toward a unified view of attention.

    PubMed

    Sörqvist, Patrik; Stenfelt, Stefan; Rönnberg, Jerker

    2012-11-01

    Two fundamental research questions have driven attention research in the past: One concerns whether selection of relevant information among competing, irrelevant, information takes place at an early or at a late processing stage; the other concerns whether the capacity of attention is limited by a central, domain-general pool of resources or by independent, modality-specific pools. In this article, we contribute to these debates by showing that the auditory-evoked brainstem response (an early stage of auditory processing) to task-irrelevant sound decreases as a function of central working memory load (manipulated with a visual-verbal version of the n-back task). Furthermore, individual differences in central/domain-general working memory capacity modulated the magnitude of the auditory-evoked brainstem response, but only in the high working memory load condition. The results support a unified view of attention whereby the capacity of a late/central mechanism (working memory) modulates early precortical sensory processing.

  9. Early childhood attention deficit hyperactivity disorder predicts poorer response to acute lithium therapy in adolescent mania.

    PubMed

    Strober, M; DeAntonio, M; Schmidt-Lackner, S; Freeman, R; Lampert, C; Diamond, J

    1998-11-01

    We compared the response to acute lithium therapy in 30 adolescents, 13-17 years of age, with mania and a prior history of early childhood attention deficit hyperactivity disorder (ADHD) to a sex- and age-matched control group of adolescent manics without premorbid psychiatric illness. Response to treatment was assessed daily over the course of 28 days using measures of global clinical improvement and severity ratings on the Bech-Rafaelsen Mania Scale (BRMS). BRMS scores decreased by a mean of 24.3 in the subgroup without prior ADHD compared to 16.7 in patients with ADHD (P = 0.0005). The average percent drop in BRMS scores over the study period in these two subgroups was 80.6% and 57.7%, respectively (P = 0.0005). Time to onset of sustained global clinical improvement was also assessed using Kaplan-Meier survival methods and possible covariates of time to improvement were tested in a Cox proportional hazards model. Median time to onset of sustained improvement was lengthened significantly in patients with early ADHD (23 days) compared to those without it (17 days; log rank chi2 = 7.2, P = 0.007). The results suggest that early childhood ADHD defines an important source of heterogeneity in bipolar illness with developmental, clinical, and neuropharmacogenetic implications. PMID:10743847

  10. Predictive regulation of associative learning in a neural network by reinforcement and attentive feedback.

    PubMed

    Grossberg, S; Levine, D; Schmajuk, N

    At least four types of learning processes are relevant in the present paper: learning of conditioned reinforcement, incentive motivation, sensory expectancy, and motor command. These several types of learning processes, which operate on a slow time scale, regulate and are regulated by rapidly fluctuating limited capacity STM representations of sensory events. The theory suggest how nonlinear feedback interactions among these fast information processing mechanisms and slow learning mechanisms participate in different conditioning paradigms, and actively regulate learning and memory to generate predictive internal representations of external environmental contingencies.

  11. A dynamic model to predict modulation sidebands of a planetary gear set having manufacturing errors

    NASA Astrophysics Data System (ADS)

    Inalpolat, Murat; Kahraman, Ahmet

    2010-02-01

    In this study, a nonlinear time-varying dynamic model is proposed to predict modulation sidebands of planetary gear sets. This discrete dynamic model includes periodically time-varying gear mesh stiffnesses and the nonlinearities associated with tooth separations. The model uses forms of gear mesh interface excitations that are amplitude and frequency modulated due to a class of gear manufacturing errors to predict dynamic forces at all sun-planet and ring-planet gear meshes. The predicted gear mesh force spectra are shown to exhibit well-defined modulation sidebands at frequencies associated with the rotational speeds of gears relative to the planet carrier. This model is further combined with a previously developed model that accounts for amplitude modulations due to rotation of the carrier to predict acceleration spectra at a fixed position in the planetary transmission housing. Individual contributions of each gear error in the form of amplitude and frequency modulations are illustrated through an example analysis. Comparisons are made to measured spectra to demonstrate the capability of the model in predicting the sidebands of a planetary gear set with gear manufacturing errors and a rotating carrier.

  12. Optimal control model predictions of system performance and attention allocation and their experimental validation in a display design study

    NASA Technical Reports Server (NTRS)

    Johannsen, G.; Govindaraj, T.

    1980-01-01

    The influence of different types of predictor displays in a longitudinal vertical takeoff and landing (VTOL) hover task is analyzed in a theoretical study. Several cases with differing amounts of predictive and rate information are compared. The optimal control model of the human operator is used to estimate human and system performance in terms of root-mean-square (rms) values and to compute optimized attention allocation. The only part of the model which is varied to predict these data is the observation matrix. Typical cases are selected for a subsequent experimental validation. The rms values as well as eye-movement data are recorded. The results agree favorably with those of the theoretical study in terms of relative differences. Better matching is achieved by revised model input data.

  13. Dopaminergic and cholinergic modulations of visual-spatial attention and working memory: insights from molecular genetic research and implications for adult cognitive development.

    PubMed

    Störmer, Viola S; Passow, Susanne; Biesenack, Julia; Li, Shu-Chen

    2012-05-01

    Attention and working memory are fundamental for selecting and maintaining behaviorally relevant information. Not only do both processes closely intertwine at the cognitive level, but they implicate similar functional brain circuitries, namely the frontoparietal and the frontostriatal networks, which are innervated by cholinergic and dopaminergic pathways. Here we review the literature on cholinergic and dopaminergic modulations of visual-spatial attention and visual working memory processes to gain insights on aging-related changes in these processes. Some extant findings have suggested that the cholinergic system plays a role in the orienting of attention to enable the detection and discrimination of visual information, whereas the dopaminergic system has mainly been associated with working memory processes such as updating and stabilizing representations. However, since visual-spatial attention and working memory processes are not fully dissociable, there is also evidence of interacting cholinergic and dopaminergic modulations of both processes. We further review gene-cognition association studies that have shown that individual differences in visual-spatial attention and visual working memory are associated with acetylcholine- and dopamine-relevant genes. The efficiency of these 2 transmitter systems declines substantially during healthy aging. These declines, in part, contribute to age-related deficits in attention and working memory functions. We report novel data showing an effect of dopamine COMT gene on spatial updating processes in older but not in younger adults, indicating potential magnification of genetic effects in old age.

  14. A neural model of cortico-cerebellar interactions during attentive imitation and predictive learning of sequential handwriting movements.

    PubMed

    Grossberg, S; Paine, R W

    2000-01-01

    Much sensory-motor behavior develops through imitation, as during the learning of handwriting by children. Such complex sequential acts are broken down into distinct motor control synergies, or muscle groups, whose activities overlap in time to generate continuous, curved movements that obey an inverse relation between curvature and speed. How are such complex movements learned through attentive imitation? Novel movements may be made as a series of distinct segments, but a practiced movement can be made smoothly, with a continuous, often bell-shaped, velocity profile. How does learning of complex movements transform reactive imitation into predictive, automatic performance? A neural model is developed which suggests how parietal and motor cortical mechanisms, such as difference vector encoding, interact with adaptively timed, predictive cerebellar learning during movement imitation and predictive performance. To initiate movement, visual attention shifts along the shape to be imitated and generates vector movement using motor cortical cells. During such an imitative movement, cerebellar Purkinje cells with a spectrum of delayed response profiles sample and learn the changing directional information and, in turn, send that learned information back to the cortex and eventually to the muscle synergies involved. If the imitative movement deviates from an attentional focus around a shape to be imitated, the visual system shifts attention, and may make an eye movement, back to the shape, thereby providing corrective directional information to the arm movement system. This imitative movement cycle repeats until the cortico-cerebellar system can accurately drive the movement based on memory alone. A cortical working memory buffer transiently stores the cerebellar output and releases it at a variable rate, allowing speed scaling of learned movements which is limited by the rate of cerebellar memory readout. Movements can be learned at variable speeds if the density of the

  15. Predictable chaos: a review of the effects of emotions on attention, memory and decision making.

    PubMed

    LeBlanc, Vicki R; McConnell, Meghan M; Monteiro, Sandra D

    2015-03-01

    Healthcare practice and education are highly emotional endeavors. While this is recognized by educators and researchers seeking to develop interventions aimed at improving wellness in health professionals and at providing them with skills to deal with emotional interpersonal situations, the field of health professions education has largely ignored the role that emotions play on cognitive processes. The purpose of this review is to provide an introduction to the broader field of emotions, with the goal of better understanding the integral relationship between emotions and cognitive processes. Individuals, at any given time, are in an emotional state. This emotional state influences how they perceive the world around them, what they recall from it, as well as the decisions they make. Rather than treating emotions as undesirable forces that wreak havoc on the rational being, the field of health professions education could be enriched by a greater understanding of how these emotions can shape cognitive processes in increasingly predictable ways. PMID:24903583

  16. Predictable chaos: a review of the effects of emotions on attention, memory and decision making.

    PubMed

    LeBlanc, Vicki R; McConnell, Meghan M; Monteiro, Sandra D

    2015-03-01

    Healthcare practice and education are highly emotional endeavors. While this is recognized by educators and researchers seeking to develop interventions aimed at improving wellness in health professionals and at providing them with skills to deal with emotional interpersonal situations, the field of health professions education has largely ignored the role that emotions play on cognitive processes. The purpose of this review is to provide an introduction to the broader field of emotions, with the goal of better understanding the integral relationship between emotions and cognitive processes. Individuals, at any given time, are in an emotional state. This emotional state influences how they perceive the world around them, what they recall from it, as well as the decisions they make. Rather than treating emotions as undesirable forces that wreak havoc on the rational being, the field of health professions education could be enriched by a greater understanding of how these emotions can shape cognitive processes in increasingly predictable ways.

  17. Event-related EEG power modulations and phase connectivity indicate the focus of attention in an auditory own name paradigm.

    PubMed

    Lechinger, Julia; Wielek, Tomasz; Blume, Christine; Pichler, Gerald; Michitsch, Gabriele; Donis, Johann; Gruber, Walter; Schabus, Manuel

    2016-08-01

    Estimating cognitive abilities in patients suffering from Disorders of Consciousness remains challenging. One cognitive task to address this issue is the so-called own name paradigm, in which subjects are presented with first names including the own name. In the active condition, a specific target name has to be silently counted. We recorded EEG during this task in 24 healthy controls, 8 patients suffering from Unresponsive Wakefulness Syndrome (UWS) and 7 minimally conscious (MCS) patients. EEG was analysed with respect to amplitude as well as phase modulations and connectivity. Results showed that general reactivity in the delta, theta and alpha frequency (event-related de-synchronisation, ERS/ERD, and phase locking between trials and electrodes) toward auditory stimulation was higher in controls than in patients. In controls, delta ERS and lower alpha ERD indexed the focus of attention in both conditions, late theta ERS only in the active condition. Additionally, phase locking between trials and delta phase connectivity was highest for own names in the passive and targets in the active condition. In patients, clear stimulus-specific differences could not be detected. However, MCS patients could reliably be differentiated from UWS patients based on their general event-related delta and theta increase independent of the type of stimulus. In conclusion, the EEG signature of the active own name paradigm revealed instruction-following in healthy participants. On the other hand, DOC patients did not show clear stimulus-specific processing. General reactivity toward any auditory input, however, allowed for a reliable differentiation between MCS and UWS patients.

  18. Dyslexia in a French-Spanish bilingual girl: behavioural and neural modulations following a visual attention span intervention.

    PubMed

    Valdois, Sylviane; Peyrin, Carole; Lassus-Sangosse, Delphine; Lallier, Marie; Démonet, Jean-François; Kandel, Sonia

    2014-04-01

    We report the case study of a French-Spanish bilingual dyslexic girl, MP, who exhibited a severe visual attention (VA) span deficit but preserved phonological skills. Behavioural investigation showed a severe reduction of reading speed for both single items (words and pseudo-words) and texts in the two languages. However, performance was more affected in French than in Spanish. MP was administered an intensive VA span intervention programme. Pre-post intervention comparison revealed a positive effect of intervention on her VA span abilities. The intervention further transferred to reading. It primarily resulted in faster identification of the regular and irregular words in French. The effect of intervention was rather modest in Spanish that only showed a tendency for faster word reading. Text reading improved in the two languages with a stronger effect in French but pseudo-word reading did not improve in either French or Spanish. The overall results suggest that VA span intervention may primarily enhance the fast global reading procedure, with stronger effects in French than in Spanish. MP underwent two fMRI sessions to explore her brain activations before and after VA span training. Prior to the intervention, fMRI assessment showed that the striate and extrastriate visual cortices alone were activated but none of the regions typically involved in VA span. Post-training fMRI revealed increased activation of the superior and inferior parietal cortices. Comparison of pre- and post-training activations revealed significant activation increase of the superior parietal lobes (BA 7) bilaterally. Thus, we show that a specific VA span intervention not only modulates reading performance but further results in increased brain activity within the superior parietal lobes known to housing VA span abilities. Furthermore, positive effects of VA span intervention on reading suggest that the ability to process multiple visual elements simultaneously is one cause of successful

  19. The functional activity and effective connectivity of pulvinar are modulated by individual differences in threat-related attentional bias

    PubMed Central

    Hakamata, Yuko; Sato, Eisuke; Komi, Shotaro; Moriguchi, Yoshiya; Izawa, Shuhei; Murayama, Norio; Hanakawa, Takashi; Inoue, Yusuke; Tagaya, Hirokuni

    2016-01-01

    The pulvinar is important in selective attention, particularly to visual stimuli under the focus of attention. However, the pulvinar is assumed to process emotional stimuli even outside the focus of attention, because of its tight connection with the amygdala. We therefore investigated how unattended emotional stimuli affect the pulvinar and its effective connectivity (EC) while considering individual differences in selective attention. fMRI in 41 healthy human subjects revealed that the amygdala, but not the pulvinar, more strongly responded to unattended fearful faces than to unattended neutral faces (UF > UN), although we observed greater EC from the pulvinar to the amygdala. Interestingly, individuals with biased attention toward threat (i.e., attentional bias) showed significantly increased activity (UF > UN) and reduced grey matter volume in the pulvinar. These individuals also exhibited stronger EC from the pulvinar to the attention-related frontoparietal network (FPN), whereas individuals with greater attentional control showed more enhanced EC from the pulvinar to the amygdala, but not the FPN (UF > UN). The pulvinar may filter unattended emotional stimuli whose sensitivity depends on individual threat-related attentional bias. The connectivity patterns of the pulvinar may thus be determined based on individual differences in threat-related attentional bias and attentional control. PMID:27703252

  20. Resting spontaneous activity in the default mode network predicts performance decline during prolonged attention workload.

    PubMed

    Gui, Danyang; Xu, Sihua; Zhu, Senhua; Fang, Zhuo; Spaeth, Andrea M; Xin, Yuanyuan; Feng, Tingyong; Rao, Hengyi

    2015-10-15

    After continuous and prolonged cognitive workload, people typically show reduced behavioral performance and increased feelings of fatigue, which are known as "time-on-task (TOT) effects". Although TOT effects are pervasive in modern life, their underlying neural mechanisms remain elusive. In this study, we induced TOT effects by administering a 20-min continuous psychomotor vigilance test (PVT) to a group of 16 healthy adults and used resting-state blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to examine spontaneous brain activity changes associated with fatigue and performance. Behaviorally, subjects displayed robust TOT effects, as reflected by increasingly slower reaction times as the test progressed and higher self-reported mental fatigue ratings after the 20-min PVT. Compared to pre-test measurements, subjects exhibited reduced amplitudes of low-frequency fluctuation (ALFF) in the default mode network (DMN) and increased ALFF in the thalamus after the test. Subjects also exhibited reduced anti-correlations between the posterior cingulate cortex (PCC) and right middle prefrontal cortex after the test. Moreover, pre-test resting ALFF in the PCC and medial prefrontal cortex (MePFC) predicted subjects' subsequent performance decline; individuals with higher ALFF in these regions exhibited more stable reaction times throughout the 20-min PVT. These results support the important role of both task-positive and task-negative networks in mediating TOT effects and suggest that spontaneous activity measured by resting-state BOLD fMRI may be a marker of mental fatigue.

  1. Resting Spontaneous Activity in the Default Mode Network Predicts Performance Decline during Prolonged Attention Workload

    PubMed Central

    Zhu, Senhua; Fang, Zhuo; Spaeth, Andrea M.; Xin, Yuanyuan; Feng, Tingyong; Rao, Hengyi

    2015-01-01

    After continuous and prolonged cognitive workload, people typically show reduced behavioral performance and increased feelings of fatigue, which are known as “time-on-task (TOT) effects”. Although TOT effects are pervasive in modern life, their underlying neural mechanisms remain elusive. In this study, we induced TOT effects by administering a 20-minute continuous psychomotor vigilance test (PVT) to a group of 16 healthy adults and used resting-state blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to examine spontaneous brain activity changes associated with fatigue and performance. Behaviorally, subjects displayed robust TOT effects, as reflected by increasingly slower reaction times as the test progressed and higher self-reported mental fatigue ratings after the 20-minute PVT. Compared to pre-test measurements, subjects exhibited reduced amplitudes of low-frequency fluctuation (ALFF) in the default mode network (DMN) and increased ALFF in the thalamus after the test. Subjects also exhibited reduced anti-correlations between the posterior cingulate cortex (PCC) and right middle prefrontal cortex after the test. Moreover, pre-test resting ALFF in the PCC and medial prefrontal cortex (MePFC) predicted subjects’ subsequent performance decline; individuals with higher ALFF in these regions exhibited more stable reaction times throughout the 20-minute PVT. These results support the important role of both task-positive and task-negative networks in mediating TOT effects and suggest that spontaneous activity measured by resting-state BOLD fMRI may be a marker of mental fatigue. PMID:26196666

  2. Stimulus-dependent activations and attention-related modulations in the auditory cortex: a meta-analysis of fMRI studies.

    PubMed

    Alho, Kimmo; Rinne, Teemu; Herron, Timothy J; Woods, David L

    2014-01-01

    We meta-analyzed 115 functional magnetic resonance imaging (fMRI) studies reporting auditory-cortex (AC) coordinates for activations related to active and passive processing of pitch and spatial location of non-speech sounds, as well as to the active and passive speech and voice processing. We aimed at revealing any systematic differences between AC surface locations of these activations by statistically analyzing the activation loci using the open-source Matlab toolbox VAMCA (Visualization and Meta-analysis on Cortical Anatomy). AC activations associated with pitch processing (e.g., active or passive listening to tones with a varying vs. fixed pitch) had median loci in the middle superior temporal gyrus (STG), lateral to Heschl's gyrus. However, median loci of activations due to the processing of infrequent pitch changes in a tone stream were centered in the STG or planum temporale (PT), significantly posterior to the median loci for other types of pitch processing. Median loci of attention-related modulations due to focused attention to pitch (e.g., attending selectively to low or high tones delivered in concurrent sequences) were, in turn, centered in the STG or superior temporal sulcus (STS), posterior to median loci for passive pitch processing. Activations due to spatial processing were centered in the posterior STG or PT, significantly posterior to pitch processing loci (processing of infrequent pitch changes excluded). In the right-hemisphere AC, the median locus of spatial attention-related modulations was in the STS, significantly inferior to the median locus for passive spatial processing. Activations associated with speech processing and those associated with voice processing had indistinguishable median loci at the border of mid-STG and mid-STS. Median loci of attention-related modulations due to attention to speech were in the same mid-STG/STS region. Thus, while attention to the pitch or location of non-speech sounds seems to recruit AC areas less

  3. Predicting borderline personality disorder symptoms in adolescents from childhood physical and relational aggression, depression, and attention-deficit/hyperactivity disorder.

    PubMed

    Vaillancourt, Tracy; Brittain, Heather L; McDougall, Patricia; Krygsman, Amanda; Boylan, Khrista; Duku, Eric; Hymel, Shelley

    2014-08-01

    Developmental cascade models linking childhood physical and relational aggression with symptoms of depression and attention-deficit/hyperactivity disorder (ADHD; assessed at ages 10, 11, 12, 13, and 14) to borderline personality disorder (BPD) features (assessed at age 14) were examined in a community sample of 484 youth. Results indicated that, when controlling for within-time covariance and across-time stability in the examination of cross-lagged relations among study variables, BPD features at age 14 were predicted by childhood relational aggression and symptoms of depression for boys, and physical and relational aggression, symptoms of depression, and symptoms of ADHD for girls. Moreover, for boys BPD features were predicted from age 10 ADHD through age 12 depression, whereas for girls the pathway to elevated BPD features at age 14 was from depression at age 10 through physical aggression symptoms at age 12. Controlling for earlier associations among variables, we found that for girls the strongest predictor of BPD features at age 14 was physical aggression, whereas for boys all the risk indicators shared a similar predictive impact. This study adds to the growing literature showing that physical and relational aggression ought to be considered when examining early precursors of BPD features.

  4. Does diagnosis affect the predictive accuracy of risk assessment tools for juvenile offenders: Conduct Disorder and Attention Deficit Hyperactivity Disorder.

    PubMed

    Khanna, Dinesh; Shaw, Jenny; Dolan, Mairead; Lennox, Charlotte

    2014-10-01

    Studies have suggested an increased risk of criminality in juveniles if they suffer from co-morbid Attention Deficit Hyperactivity Disorder (ADHD) along with Conduct Disorder. The Structured Assessment of Violence Risk in Youth (SAVRY), the Psychopathy Checklist Youth Version (PCL:YV), and Youth Level of Service/Case Management Inventory (YLS/CMI) have been shown to be good predictors of violent and non-violent re-offending. The aim was to compare the accuracy of these tools to predict violent and non-violent re-offending in young people with co-morbid ADHD and Conduct Disorder and Conduct Disorder only. The sample included 109 White-British adolescent males in secure settings. Results revealed no significant differences between the groups for re-offending. SAVRY factors had better predictive values than PCL:YV or YLS/CMI. Tools generally had better predictive values for the Conduct Disorder only group than the co-morbid group. Possible reasons for these findings have been discussed along with limitations of the study. PMID:25173178

  5. How Does Awareness Modulate Goal-Directed and Stimulus-Driven Shifts of Attention Triggered by Value Learning?

    PubMed Central

    Bourgeois, Alexia; Neveu, Rémi; Vuilleumier, Patrik

    2016-01-01

    In order to behave adaptively, attention can be directed in space either voluntarily (i.e., endogenously) according to strategic goals, or involuntarily (i.e., exogenously) through reflexive capture by salient or novel events. The emotional or motivational value of stimuli can also strongly influence attentional orienting. However, little is known about how reward-related effects compete or interact with endogenous and exogenous attention mechanisms, particularly outside of awareness. Here we developed a visual search paradigm to study subliminal value-based attentional orienting. We systematically manipulated goal-directed or stimulus-driven attentional orienting and examined whether an irrelevant, but previously rewarded stimulus could compete with both types of spatial attention during search. Critically, reward was learned without conscious awareness in a preceding phase where one among several visual symbols was consistently paired with a subliminal monetary reinforcement cue. Our results demonstrated that symbols previously associated with a monetary reward received higher attentional priority in the subsequent visual search task, even though these stimuli and reward were no longer task-relevant, and despite reward being unconsciously acquired. Thus, motivational processes operating independent of conscious awareness may provide powerful influences on mechanisms of attentional selection, which could mitigate both stimulus-driven and goal-directed shifts of attention. PMID:27483371

  6. Dopamine and the Management of Attentional Resources: Genetic Markers of Striatal D2 Dopamine Predict Individual Differences in the Attentional Blink

    ERIC Educational Resources Information Center

    Colzato, Lorenza S.; Slagter, Heleen A.; de Rover, Mischa; Hommel, Bernhard

    2011-01-01

    The attentional blink (AB)--a deficit in reporting the second of two target stimuli presented in close succession in a rapid sequence of distracters--has been related to processing limitations in working memory. Given that dopamine (DA) plays a crucial role working memory, the present study tested whether individual differences in the size of the…

  7. Prediction of Participation and Sensory Modulation of Late Preterm Infants at 12 Months: A Prospective Study

    ERIC Educational Resources Information Center

    Bart, O.; Shayevits, S.; Gabis, L. V.; Morag, I.

    2011-01-01

    The aim of the study was to prospectively assess the differences in participation and sensory modulation between late preterm infants (LPI) and term babies, and to predict it by LPI characteristics. The study population includes 124 late preterm infants at gestational age between 34 and 35 6/7 weeks who were born at the same medical center. The…

  8. Low Fidelity Imitation of Atypical Biological Kinematics in Autism Spectrum Disorders Is Modulated by Self-Generated Selective Attention

    ERIC Educational Resources Information Center

    Hayes, Spencer J.; Andrew, Matthew; Elliott, Digby; Gowen, Emma; Bennett, Simon J.

    2016-01-01

    We examined whether adults with autism had difficulty imitating atypical biological kinematics. To reduce the impact that higher-order processes have on imitation we used a non-human agent model to control social attention, and removed end-state target goals in half of the trials to minimise goal-directed attention. Findings showed that only…

  9. Both a Nicotinic Single Nucleotide Polymorphism (SNP) and a Noradrenergic SNP Modulate Working Memory Performance when Attention Is Manipulated

    ERIC Educational Resources Information Center

    Greenwood, Pamela M.; Sundararajan, Ramya; Lin, Ming-Kuan; Kumar, Reshma; Fryxell, Karl J.; Parasuraman, Raja

    2009-01-01

    We investigated the relation between the two systems of visuospatial attention and working memory by examining the effect of normal variation in cholinergic and noradrenergic genes on working memory performance under attentional manipulation. We previously reported that working memory for location was impaired following large location precues,…

  10. Modulation in the mirror neuron system when action prediction is not satisfied.

    PubMed

    Plata Bello, Julio; Modroño, Cristián; Marcano, Francisco; González-Mora, José Luis

    2015-04-01

    The ability to understand competitive games is closely connected to the mirror neuron system (MNS). This network is activated not only when an action is performed, but also when it is observed. Apart from allowing the understanding of actions performed by others, the MNS has been implicated in predicting subsequent actions. However, the results concerning the modulation of this network by the final outcome of these predictions are contradictory. These contradictions may be related to the use of complex experimental conditions. The aim of this research is to identify changes in the activity of the MNS when the predictions are or are not satisfied in a simple intransitive action-based game. An event-related functional magnetic resonance imaging study was conducted. It consisted of the observation of videos with two actors playing the well-known rock-paper-scissors game. The participants were asked to predict the response of the second actor when the first actor performed one of the three possible actions. In some videos (congruents) the prediction was satisfied, but in the rest of the videos (incongruents) the prediction was not satisfied. When the result was shown, higher activity in the MNS was observed in the congruent videos than in the incongruent ones. Therefore, the observation of a simple manual game leads to a significant activation of the MNS, and this activity seems to be modulated by the final outcome of a prediction, and when predictions are satisfied the activity is higher.

  11. Learning new gait patterns: Exploratory muscle activity during motor learning is not predicted by motor modules.

    PubMed

    Ranganathan, Rajiv; Krishnan, Chandramouli; Dhaher, Yasin Y; Rymer, William Z

    2016-03-21

    The motor module hypothesis in motor control proposes that the nervous system can simplify the problem of controlling a large number of muscles in human movement by grouping muscles into a smaller number of modules. Here, we tested one prediction of the modular organization hypothesis by examining whether there is preferential exploration along these motor modules during the learning of a new gait pattern. Healthy college-aged participants learned a new gait pattern which required increased hip and knee flexion during the swing phase while walking in a lower-extremity robot (Lokomat). The new gait pattern was displayed as a foot trajectory in the sagittal plane and participants attempted to match their foot trajectory to this template. We recorded EMG from 8 lower-extremity muscles and we extracted motor modules during both baseline walking and target-tracking using non-negative matrix factorization (NMF). Results showed increased trajectory variability in the first block of learning, indicating that participants were engaged in exploratory behavior. Critically, when we examined the muscle activity during this exploratory phase, we found that the composition of motor modules changed significantly within the first few strides of attempting the new gait pattern. The lack of persistence of the motor modules under even short time scales suggests that motor modules extracted during locomotion may be more indicative of correlated muscle activity induced by the task constraints of walking, rather than reflecting a modular control strategy.

  12. Dissecting Neural Responses to Temporal Prediction, Attention, and Memory: Effects of Reward Learning and Interoception on Time Perception.

    PubMed

    Tomasi, Dardo; Wang, Gene-Jack; Studentsova, Yana; Volkow, Nora D

    2015-10-01

    Temporal prediction (TP) is needed to anticipate future events and is essential for survival. Our sense of time is modulated by emotional and interoceptive (corporal) states that are hypothesized to rely on a dopamine (DA)-modulated "internal clock" in the basal ganglia. However, the neurobiological substrates for TP in the human brain have not been identified. We tested the hypothesis that TP involves DA striato-cortical pathways, and that accurate responses are reinforcing in themselves and activate the nucleus accumbens (NAc). Functional magnetic resonance imaging revealed the involvement of the NAc and anterior insula in the temporal precision of the responses, and of the ventral tegmental area in error processing. Moreover, NAc showed higher activation for successful than for unsuccessful trials, indicating that accurate TP per se is rewarding. Inasmuch as activation of the NAc is associated with drug-induced addictive behaviors, its activation by accurate TP could help explain why video games that rely on TP can trigger compulsive behaviors. PMID:25389123

  13. Dissecting Neural Responses to Temporal Prediction, Attention, and Memory: Effects of Reward Learning and Interoception on Time Perception

    PubMed Central

    Tomasi, Dardo; Wang, Gene-Jack; Studentsova, Yana; Volkow, Nora D.

    2015-01-01

    Temporal prediction (TP) is needed to anticipate future events and is essential for survival. Our sense of time is modulated by emotional and interoceptive (corporal) states that are hypothesized to rely on a dopamine (DA)-modulated “internal clock” in the basal ganglia. However, the neurobiological substrates for TP in the human brain have not been identified. We tested the hypothesis that TP involves DA striato-cortical pathways, and that accurate responses are reinforcing in themselves and activate the nucleus accumbens (NAc). Functional magnetic resonance imaging revealed the involvement of the NAc and anterior insula in the temporal precision of the responses, and of the ventral tegmental area in error processing. Moreover, NAc showed higher activation for successful than for unsuccessful trials, indicating that accurate TP per se is rewarding. Inasmuch as activation of the NAc is associated with drug-induced addictive behaviors, its activation by accurate TP could help explain why video games that rely on TP can trigger compulsive behaviors. PMID:25389123

  14. Motor Consciousness during Intention-Based and Stimulus-Based Actions: Modulating Attention Resources through Mindfulness Meditation

    PubMed Central

    Delevoye-Turrell, Yvonne Nathalie; Bobineau, Claudie

    2012-01-01

    Mindfulness-Based Stress Reduction meditation (MBSR) may offer optimal performance through heightened attention for increased body consciousness. To test this hypothesis, MBSR effects were assessed on the simple task of lifting an object. A dual task paradigm was included to assess the opposite effect of a limited amount of attention on motor consciousness. In a stimulus-based condition, the subjects’ task was to lift an object that was hefted with weights. In an intentional-based condition, subjects were required to lift a light object while imagining that the object was virtually heavier and thus, adjust their grip voluntarily. The degree of motor consciousness was evaluated by calculating correlation factors for each participant between the grip force level used during the lift trial (“lift the object”) and that used during its associated reproduce trial (“without lifting, indicate the force you think you used in the previous trial”). Under dual task condition, motor consciousness decreased for intention- and stimulus-based actions, revealing the importance of top-down attention for building the motor representation that guides action planning. For MBSR-experts, heightened attention provided stronger levels of motor consciousness; this was true for both intention and stimulus-based actions. For controls, heightened attention decreased the capacity to reproduce force levels, suggesting that voluntary top-down attention interfered with the automatic bottom-up emergence of body sensations. Our results provide strong arguments for involvement of two types of attention for the emergence of motor consciousness. Bottom-up attention would serve as an amplifier of motor-sensory afferences; top-down attention would help transfer the motor-sensory content from a preconscious to a conscious state of processing. MBSR would be a specific state for which both types of attention are optimally combined to provide experts with total experiences of their body in movement

  15. Visuo-motor coordination ability predicts performance with brain-computer interfaces controlled by modulation of sensorimotor rhythms (SMR).

    PubMed

    Hammer, Eva M; Kaufmann, Tobias; Kleih, Sonja C; Blankertz, Benjamin; Kübler, Andrea

    2014-01-01

    Modulation of sensorimotor rhythms (SMR) was suggested as a control signal for brain-computer interfaces (BCI). Yet, there is a population of users estimated between 10 to 50% not able to achieve reliable control and only about 20% of users achieve high (80-100%) performance. Predicting performance prior to BCI use would facilitate selection of the most feasible system for an individual, thus constitute a practical benefit for the user, and increase our knowledge about the correlates of BCI control. In a recent study, we predicted SMR-BCI performance from psychological variables that were assessed prior to the BCI sessions and BCI control was supported with machine-learning techniques. We described two significant psychological predictors, namely the visuo-motor coordination ability and the ability to concentrate on the task. The purpose of the current study was to replicate these results thereby validating these predictors within a neurofeedback based SMR-BCI that involved no machine learning.Thirty-three healthy BCI novices participated in a calibration session and three further neurofeedback training sessions. Two variables were related with mean SMR-BCI performance: (1) a measure for the accuracy of fine motor skills, i.e., a trade for a person's visuo-motor control ability; and (2) subject's "attentional impulsivity". In a linear regression they accounted for almost 20% in variance of SMR-BCI performance, but predictor (1) failed significance. Nevertheless, on the basis of our prior regression model for sensorimotor control ability we could predict current SMR-BCI performance with an average prediction error of M = 12.07%. In more than 50% of the participants, the prediction error was smaller than 10%. Hence, psychological variables played a moderate role in predicting SMR-BCI performance in a neurofeedback approach that involved no machine learning. Future studies are needed to further consolidate (or reject) the present predictors.

  16. Visuo-motor coordination ability predicts performance with brain-computer interfaces controlled by modulation of sensorimotor rhythms (SMR)

    PubMed Central

    Hammer, Eva M.; Kaufmann, Tobias; Kleih, Sonja C.; Blankertz, Benjamin; Kübler, Andrea

    2014-01-01

    Modulation of sensorimotor rhythms (SMR) was suggested as a control signal for brain-computer interfaces (BCI). Yet, there is a population of users estimated between 10 to 50% not able to achieve reliable control and only about 20% of users achieve high (80–100%) performance. Predicting performance prior to BCI use would facilitate selection of the most feasible system for an individual, thus constitute a practical benefit for the user, and increase our knowledge about the correlates of BCI control. In a recent study, we predicted SMR-BCI performance from psychological variables that were assessed prior to the BCI sessions and BCI control was supported with machine-learning techniques. We described two significant psychological predictors, namely the visuo-motor coordination ability and the ability to concentrate on the task. The purpose of the current study was to replicate these results thereby validating these predictors within a neurofeedback based SMR-BCI that involved no machine learning.Thirty-three healthy BCI novices participated in a calibration session and three further neurofeedback training sessions. Two variables were related with mean SMR-BCI performance: (1) a measure for the accuracy of fine motor skills, i.e., a trade for a person’s visuo-motor control ability; and (2) subject’s “attentional impulsivity”. In a linear regression they accounted for almost 20% in variance of SMR-BCI performance, but predictor (1) failed significance. Nevertheless, on the basis of our prior regression model for sensorimotor control ability we could predict current SMR-BCI performance with an average prediction error of M = 12.07%. In more than 50% of the participants, the prediction error was smaller than 10%. Hence, psychological variables played a moderate role in predicting SMR-BCI performance in a neurofeedback approach that involved no machine learning. Future studies are needed to further consolidate (or reject) the present predictors. PMID:25147518

  17. Effects of Attention on the Strength of Lexical Influences on Speech Perception: Behavioral Experiments and Computational Mechanisms

    PubMed Central

    Mirman, Daniel; McClelland, James L.; Holt, Lori L.; Magnuson, James S.

    2008-01-01

    The effects of lexical context on phonological processing are pervasive and there have been indications that such effects may be modulated by attention. However, attentional modulation in speech processing is neither well-documented nor well-understood. Experiment 1 demonstrated attentional modulation of lexical facilitation of speech sound recognition when task and critical stimuli were identical across attention conditions. We propose modulation of lexical activation as a neurophysiologically-plausible computational mechanism that can account for this type of modulation. Contrary to the claims of critics, this mechanism can account for attentional modulation without violating the principle of interactive processing. Simulations of the interactive TRACE model extended to include two different ways of modulating lexical activation showed that each can account for attentional modulation of lexical feedback effects. Experiment 2 tested conflicting predictions from the two implementations and provided evidence that is consistent with bias input as the mechanism of attentional control of lexical activation. PMID:18509503

  18. Social identity-based motivation modulates attention bias toward negative information: an event-related brain potential study

    PubMed Central

    Montalan, Benoît; Boitout, Alexis; Veujoz, Mathieu; Leleu, Arnaud; Germain, Raymonde; Personnaz, Bernard; Lalonde, Robert; Rebaï, Mohamed

    2011-01-01

    Research has demonstrated that people readily pay more attention to negative than to positive and/or neutral stimuli. However, evidence from recent studies indicated that such an attention bias to negative information is not obligatory but sensitive to various factors. Two experiments using intergroup evaluative tasks (Study 1: a gender-related groups evaluative task and Study 2: a minimal-related groups evaluative task) was conducted to determine whether motivation to strive for a positive social identity – a part of one’s self-concept – drives attention toward affective stimuli. Using the P1 component of event-related brain potentials (ERPs) as a neural index of attention, we confirmed that attention bias toward negative stimuli is not mandatory but it can depend on a motivational focus on affective outcomes. Results showed that social identity-based motivation is likely to bias attention toward affectively incongruent information. Thereby, early onset processes – reflected by the P1 component – appeared susceptible to top-down attentional influences induced by the individual’s motivation to strive for a positive social identity. PMID:24693339

  19. Social identity-based motivation modulates attention bias toward negative information: an event-related brain potential study.

    PubMed

    Montalan, Benoît; Boitout, Alexis; Veujoz, Mathieu; Leleu, Arnaud; Germain, Raymonde; Personnaz, Bernard; Lalonde, Robert; Rebaï, Mohamed

    2011-01-01

    Research has demonstrated that people readily pay more attention to negative than to positive and/or neutral stimuli. However, evidence from recent studies indicated that such an attention bias to negative information is not obligatory but sensitive to various factors. Two experiments using intergroup evaluative tasks (Study 1: a gender-related groups evaluative task and Study 2: a minimal-related groups evaluative task) was conducted to determine whether motivation to strive for a positive social identity - a part of one's self-concept - drives attention toward affective stimuli. Using the P1 component of event-related brain potentials (ERPs) as a neural index of attention, we confirmed that attention bias toward negative stimuli is not mandatory but it can depend on a motivational focus on affective outcomes. Results showed that social identity-based motivation is likely to bias attention toward affectively incongruent information. Thereby, early onset processes - reflected by the P1 component - appeared susceptible to top-down attentional influences induced by the individual's motivation to strive for a positive social identity.

  20. Sleep problems predict comorbid externalizing behaviors and depression in young adolescents with attention-deficit/hyperactivity disorder.

    PubMed

    Becker, Stephen P; Langberg, Joshua M; Evans, Steven W

    2015-08-01

    Children and adolescents with attention-deficit/hyperactivity disorder (ADHD) experience high rates of sleep problems and are also at increased risk for experiencing comorbid mental health problems. This study provides an initial examination of the 1-year prospective association between sleep problems and comorbid symptoms in youth diagnosed with ADHD. Participants were 81 young adolescents (75 % male) carefully diagnosed with ADHD and their parents. Parents completed measures of their child's sleep problems and ADHD symptoms, oppositional defiant disorder (ODD) symptoms, and general externalizing behavior problems at baseline (M age = 12.2) and externalizing behaviors were assessed again 1 year later. Adolescents completed measures of anxiety and depression at both time-points. Medication use was not associated with sleep problems or comorbid psychopathology symptoms. Regression analyses indicated that, above and beyond demographic characteristics, ADHD symptom severity, and initial levels of comorbidity, sleep problems significantly predicted greater ODD symptoms, general externalizing behavior problems, and depressive symptoms 1 year later. Sleep problems were not concurrently or prospectively associated with anxiety. Although this study precludes making causal inferences, it does nonetheless provide initial evidence of sleep problems predicting later comorbid externalizing behaviors and depression symptoms in youth with ADHD. Additional research is needed with larger samples and multiple time-points to further examine the interrelations of sleep problems and comorbidity.

  1. The strength of the corticospinal coherence depends on the predictability of modulated isometric forces.

    PubMed

    Mendez-Balbuena, Ignacio; Naranjo, Jose Raul; Wang, Xi; Andrykiewicz, Agnieska; Huethe, Frank; Schulte-Mönting, Jürgen; Hepp-Reymond, Marie-Claude; Kristeva, Rumyana

    2013-03-01

    Isometric compensation of predictably frequency-modulated low forces is associated with corticomuscular coherence (CMC) in beta and low gamma range. It remains unclear how the CMC is influenced by unpredictably modulated forces, which create a mismatch between expected and actual sensory feedback. We recorded electroencephalography from the contralateral hand motor area, electromyography (EMG), and the motor performance of 16 subjects during a visuomotor task in which they had to isometrically compensate target forces at 8% of the maximum voluntary contraction with their right index finger. The modulated forces were presented with predictable or unpredictable frequencies. We calculated the CMC, the cortical motor alpha-, beta-, and gamma-range spectral powers (SP), and the task-related desynchronization (TRD), as well as the EMG SP and the performance. We found that in the unpredictable condition the CMC was significantly lower and associated with lower cortical motor SP, stronger TRD, higher EMG SP, and worse performance. The findings suggest that due to the mismatch between predicted and actual sensory feedback leading to higher computational load and less stationary motor state, the unpredictable modulation of the force leads to a decrease in corticospinal synchrony, an increase in cortical and muscle activation, and a worse performance.

  2. Top-down modulation in human visual cortex predicts the stability of a perceptual illusion.

    PubMed

    Kloosterman, Niels A; Meindertsma, Thomas; Hillebrand, Arjan; van Dijk, Bob W; Lamme, Victor A F; Donner, Tobias H

    2015-02-15

    Conscious perception sometimes fluctuates strongly, even when the sensory input is constant. For example, in motion-induced blindness (MIB), a salient visual target surrounded by a moving pattern suddenly disappears from perception, only to reappear after some variable time. Whereas such changes of perception result from fluctuations of neural activity, mounting evidence suggests that the perceptual changes, in turn, may also cause modulations of activity in several brain areas, including visual cortex. In this study, we asked whether these latter modulations might affect the subsequent dynamics of perception. We used magnetoencephalography (MEG) to measure modulations in cortical population activity during MIB. We observed a transient, retinotopically widespread modulation of beta (12-30 Hz)-frequency power over visual cortex that was closely linked to the time of subjects' behavioral report of the target disappearance. This beta modulation was a top-down signal, decoupled from both the physical stimulus properties and the motor response but contingent on the behavioral relevance of the perceptual change. Critically, the modulation amplitude predicted the duration of the subsequent target disappearance. We propose that the transformation of the perceptual change into a report triggers a top-down mechanism that stabilizes the newly selected perceptual interpretation. PMID:25411458

  3. Top-down modulation in human visual cortex predicts the stability of a perceptual illusion

    PubMed Central

    Meindertsma, Thomas; Hillebrand, Arjan; van Dijk, Bob W.; Lamme, Victor A. F.; Donner, Tobias H.

    2014-01-01

    Conscious perception sometimes fluctuates strongly, even when the sensory input is constant. For example, in motion-induced blindness (MIB), a salient visual target surrounded by a moving pattern suddenly disappears from perception, only to reappear after some variable time. Whereas such changes of perception result from fluctuations of neural activity, mounting evidence suggests that the perceptual changes, in turn, may also cause modulations of activity in several brain areas, including visual cortex. In this study, we asked whether these latter modulations might affect the subsequent dynamics of perception. We used magnetoencephalography (MEG) to measure modulations in cortical population activity during MIB. We observed a transient, retinotopically widespread modulation of beta (12–30 Hz)-frequency power over visual cortex that was closely linked to the time of subjects' behavioral report of the target disappearance. This beta modulation was a top-down signal, decoupled from both the physical stimulus properties and the motor response but contingent on the behavioral relevance of the perceptual change. Critically, the modulation amplitude predicted the duration of the subsequent target disappearance. We propose that the transformation of the perceptual change into a report triggers a top-down mechanism that stabilizes the newly selected perceptual interpretation. PMID:25411458

  4. Comparing the executive attention of adult females with ADHD to that of females with sensory modulation disorder (SMD) under aversive and non-aversive auditory conditions.

    PubMed

    Mazor-Karsenty, Tal; Parush, Shula; Bonneh, Yoram; Shalev, Lilach

    2015-02-01

    Certain behavioral expressions of sensory modulation disorder (SMD) such as distractibility, hyperactivity, and impulsivity are often similar to those of attention deficit/hyperactivity disorder (ADHD) in pediatric and adult populations. There is also a high comorbidity rate between these two diagnoses and absence of research regarding the objective neuropsychological differentiation between them. In the present study we employed a factorial design which enabled us to: (a) systematically examine the effects of SMD and ADHD on executive attention in a sample of adult females using a Stroop-like task, and (b) measure the effect of aversive conditions (sounds) on executive attention. The experimental measures used were the Stroop-like Location-Direction Task (SLDT) to assess executive attention and the battery of aversiveness to sounds (BAS), a standardized measure of aversive sounds that was developed for this study and enabled individual customization of aversive auditory sounds. Results revealed, as expected, a specific core deficit in executive attention for the ADHD factor. In addition to that, the present study provides an important, pioneering finding of SMD impairment in a unique combination of a cognitively demanding task with aversive sounds, providing preliminary objective evidence differentiating SMD from ADHD.

  5. Broad Autism Phenotype in Typically Developing Children Predicts Performance on an Eye-Tracking Measure of Joint Attention

    ERIC Educational Resources Information Center

    Swanson, Meghan R.; Serlin, Gayle C.; Siller, Michael

    2013-01-01

    We examined visual attention allocation during a set of social videos that are intended to elicit the coordination of attention with another person, compared to a control condition. Deficits in joint attention are a characteristic of young children with autism spectrum disorder (ASD). Participants included a diverse sample of 50 typically…

  6. The Social Modulation of Pain: Others as Predictive Signals of Salience – a Systematic Review

    PubMed Central

    Krahé, Charlotte; Springer, Anne; Weinman, John A.; Fotopoulou, Aikaterini

    2013-01-01

    Several studies in cognitive neuroscience have investigated the cognitive and affective modulation of pain. By contrast, fewer studies have focused on the social modulation of pain, despite a plethora of relevant clinical findings. Here we present the first review of experimental studies addressing how interpersonal factors, such as the presence, behavior, and spatial proximity of an observer, modulate pain. Based on a systematic literature search, we identified 26 studies on experimentally induced pain that manipulated different interpersonal variables and measured behavioral, physiological, and neural pain-related responses. We observed that the modulation of pain by interpersonal factors depended on (1) the degree to which the social partners were active or were perceived by the participants to possess possibility for action; (2) the degree to which participants could perceive the specific intentions of the social partners; (3) the type of pre-existing relationship between the social partner and the person in pain, and lastly, (4) individual differences in relating to others and coping styles. Based on these findings, we propose that the modulation of pain by social factors can be fruitfully understood in relation to a recent predictive coding model, the free energy framework, particularly as applied to interoception and social cognition. Specifically, we argue that interpersonal interactions during pain may function as social, predictive signals of contextual threat or safety and as such influence the salience of noxious stimuli. The perception of such interpersonal interactions may in turn depend on (a) prior beliefs about interpersonal relating and (b) the certainty or precision by which an interpersonal interaction may predict environmental threat or safety. PMID:23888136

  7. Performance Prediction of Commercial Thermoelectric Cooler Modules using the Effective Material Properties

    NASA Astrophysics Data System (ADS)

    Lee, HoSung; Attar, Alaa M.; Weera, Sean L.

    2015-06-01

    This work examines the validity of formulating the effective thermoelectric material properties as a way to predict thermoelectric module performance. The three maximum parameters (temperature difference, current, and cooling power) of a thermoelectric cooler were formulated on the basis of the hot junction temperature. Then, the effective material properties (Seebeck coefficient, electrical resistance, and thermal conductivity) were defined in terms of the three maximum parameters that were taken from either a commercial thermoelectric cooler module or the measurements. It is demonstrated that the simple standard equation with the effective material properties predicts well the performance curves of the four selected commercial products. Normalized parameters over the maximum parameters were also formulated to present the characteristics of the thermoelectric coolers along with the normalized charts. The normalized charts would be universal for a given thermoelectric material.

  8. A simplified ab initio cosmic-ray modulation model: construction and predictive capabilities

    NASA Astrophysics Data System (ADS)

    Moloto, Katlego; Burger, Renier; Engelbrecht, Nicholas

    2016-07-01

    A simplified ab initio approach is followed to model cosmic-ray modulation using a steady-state three-dimensional stochastic solver of the Parker transport equation. Standard diffusion coefficients based on Quasilinear Theory (QLT) and Nonlinear Guiding Center Theory (NLGC) are used. The spatial dependence of turbulence quantities required as input for the drift- and diffusion coefficients, follow from parametric fits to results from a turbulence transport model. Effective values are used for the solar wind speed, magnetic field magnitude and tilt angle in the modulation model. The unusually high cosmic-ray intensities observed during the 2009 solar minimum follow naturally from the current model for most of the energies considered. This demonstrates that changes in turbulence contribute significantly to than usual cosmic-ray intensities during the 2009 solar minimum. We also discuss and illustrate how this model can be used to predict future cosmic-ray intensities, and comment on the reliability of such predictions.

  9. Dopamine and serotonin genetic risk scores predicting substance and nicotine use in attention deficit/hyperactivity disorder.

    PubMed

    Groenman, Annabeth P; Greven, Corina U; van Donkelaar, Marjolein M J; Schellekens, Arnt; van Hulzen, Kimm J E; Rommelse, Nanda; Hartman, Catharina A; Hoekstra, Pieter J; Luman, Marjolein; Franke, Barbara; Faraone, Stephen V; Oosterlaan, Jaap; Buitelaar, Jan K

    2016-07-01

    Individuals with attention deficit/hyperactivity disorder (ADHD) are at increased risk of developing substance use disorders (SUDs) and nicotine dependence. The co-occurrence of ADHD and SUDs/nicotine dependence may in part be mediated by shared genetic liability. Several neurobiological pathways have been implicated in both ADHD and SUDs, including dopamine and serotonin pathways. We hypothesized that variations in dopamine and serotonin neurotransmission genes were involved in the genetic liability to develop SUDs/nicotine dependence in ADHD. The current study included participants with ADHD (n = 280) who were originally part of the Dutch International Multicenter ADHD Genetics study. Participants were aged 5-15 years and attending outpatient clinics at enrollment in the study. Diagnoses of ADHD, SUDs, nicotine dependence, age of first nicotine and substance use, and alcohol use severity were based on semi-structured interviews and questionnaires. Genetic risk scores were created for both serotonergic and dopaminergic risk genes previously shown to be associated with ADHD and SUDs and/or nicotine dependence. The serotonin genetic risk score significantly predicted alcohol use severity. No significant serotonin × dopamine risk score or effect of stimulant medication was found. The current study adds to the literature by providing insight into genetic underpinnings of the co-morbidity of ADHD and SUDs. While the focus of the literature so far has been mostly on dopamine, our study suggests that serotonin may also play a role in the relationship between these disorders. PMID:25752199

  10. Serotonin modulates the effects of Pavlovian aversive predictions on response vigor.

    PubMed

    Crockett, Molly J; Clark, Luke; Apergis-Schoute, Annemieke M; Morein-Zamir, Sharon; Robbins, Trevor W

    2012-09-01

    Updated theoretical accounts of the role of serotonin (5-HT) in motivation propose that 5-HT operates at the intersection of aversion and inhibition, promoting withdrawal in the face of aversive predictions. However, the specific cognitive mechanisms through which 5-HT modulates withdrawal behavior remain poorly understood. Behavioral inhibition in response to punishments reflects at least two concurrent processes: instrumental aversive predictions linking stimuli, responses, and punishments, and Pavlovian aversive predictions linking stimuli and punishments irrespective of response. In the current study, we examined to what extent 5-HT modulates the impact of instrumental vs Pavlovian aversive predictions on behavioral inhibition. We used acute tryptophan depletion to lower central 5-HT levels in healthy volunteers, and observed behavior in a novel task designed to measure the influence of Pavlovian and instrumental aversive predictions on choice (response bias) and response vigor (response latencies). After placebo treatment, participants were biased against responding on the button that led to punishment, and they were slower to respond in a punished context, relative to a non-punished context. Specifically, participants slowed their responses in the presence of stimuli predictive of punishments. Tryptophan depletion removed the bias against responding on the punished button, and abolished slowing in the presence of punished stimuli, irrespective of response. We suggest that this set of results can be explained by a role for 5-HT in Pavlovian aversive predictions. These findings suggest additional specificity for the influence of 5-HT on aversively motivated behavioral inhibition and extend recent models of the role of 5-HT in aversive predictions. PMID:22643930

  11. Shared Attention.

    PubMed

    Shteynberg, Garriy

    2015-09-01

    Shared attention is extremely common. In stadiums, public squares, and private living rooms, people attend to the world with others. Humans do so across all sensory modalities-sharing the sights, sounds, tastes, smells, and textures of everyday life with one another. The potential for attending with others has grown considerably with the emergence of mass media technologies, which allow for the sharing of attention in the absence of physical co-presence. In the last several years, studies have begun to outline the conditions under which attending together is consequential for human memory, motivation, judgment, emotion, and behavior. Here, I advance a psychological theory of shared attention, defining its properties as a mental state and outlining its cognitive, affective, and behavioral consequences. I review empirical findings that are uniquely predicted by shared-attention theory and discuss the possibility of integrating shared-attention, social-facilitation, and social-loafing perspectives. Finally, I reflect on what shared-attention theory implies for living in the digital world. PMID:26385997

  12. Prediction of Fault-Prone Software Modules Using a Generic Text Discriminator

    NASA Astrophysics Data System (ADS)

    Mizuno, Osamu; Kikuno, Tohru

    This paper describes a novel approach for detecting fault-prone modules using a spam filtering technique. Fault-prone module detection in source code is important for the assurance of software quality. Most previous fault-prone detection approaches have been based on using software metrics. Such approaches, however, have difficulties in collecting the metrics and constructing mathematical models based on the metrics. Because of the increase in the need for spam e-mail detection, the spam filtering technique has progressed as a convenient and effective technique for text mining. In our approach, fault-prone modules are detected in such a way that the source code modules are considered text files and are applied to the seam filter directly. To show the applicability of our approach, we conducted experimental applications using source code repositories of Java based open source developments. The result of experiments shows that our approach can correctly predict 78% of actual fault-prone modules as fault-prone.

  13. Prediction of participation and sensory modulation of late preterm infants at 12 months: a prospective study.

    PubMed

    Bart, O; Shayevits, S; Gabis, L V; Morag, I

    2011-01-01

    The aim of the study was to prospectively assess the differences in participation and sensory modulation between late preterm infants (LPI) and term babies, and to predict it by LPI characteristics. The study population includes 124 late preterm infants at gestational age between 34 and 35 6/7 weeks who were born at the same medical center. The control group comprised of 33 term babies (18 boys, 15 girls), born during the same period and location (mean age 12.47, SD = 0.73). Sensory modulation was assessed by the test of sensory functions in infants and the infant/toddler sensory profile and for assessment of participation and parents' satisfaction we used questionnaires. Term infants had better sensory modulation than LPI. Approximately 10% of the sensory modulation of participants in the study was explained by gestational age and head circumference. LPI participation and parental satisfaction decreased in the LPI group. Among all the explanatory variables only multiple gestations and head circumference contributed to the explained variance of participation (16%), and parents' satisfaction (13%). At age of 1 year, children born as late preterm are at increased risk of developing sensory modulation disorder, showing less participation, and resulting in less parental satisfaction. PMID:21742470

  14. Temporal prediction modulates the evaluative processing of "good" action feedback: An electrophysiological study.

    PubMed

    Kimura, Kenta; Kimura, Motohiro; Iwaki, Sunao

    2016-10-01

    The present study aimed to investigate whether or not the evaluative processing of action feedback can be modulated by temporal prediction. For this purpose, we examined the effects of the predictability of the timing of action feedback on an ERP effect that indexed the evaluative processing of action feedback, that is, an ERP effect that has been interpreted as a feedback-related negativity (FRN) elicited by "bad" action feedback or a reward positivity (RewP) elicited by "good" action feedback. In two types of experimental blocks, the participants performed a gambling task in which they chose one of two cards and received an action feedback that indicated monetary gain or loss. In fixed blocks, the time interval between the participant's choice and the onset of the action feedback was fixed at 0, 500, or 1,000 ms in separate blocks; thus, the timing of action feedback was predictable. In mixed blocks, the time interval was randomly chosen from the same three intervals with equal probability; thus, the timing was less predictable. The results showed that the FRN/RewP was smaller in mixed than fixed blocks for the 0-ms interval trial, whereas there was no difference between the two block types for the 500-ms and 1,000-ms interval trials. Interestingly, the smaller FRN/RewP was due to the modulation of gain ERPs rather than loss ERPs. These results suggest that temporal prediction can modulate the evaluative processing of action feedback, and particularly good feedback, such as that which indicates monetary gain.

  15. Temporal prediction modulates the evaluative processing of "good" action feedback: An electrophysiological study.

    PubMed

    Kimura, Kenta; Kimura, Motohiro; Iwaki, Sunao

    2016-10-01

    The present study aimed to investigate whether or not the evaluative processing of action feedback can be modulated by temporal prediction. For this purpose, we examined the effects of the predictability of the timing of action feedback on an ERP effect that indexed the evaluative processing of action feedback, that is, an ERP effect that has been interpreted as a feedback-related negativity (FRN) elicited by "bad" action feedback or a reward positivity (RewP) elicited by "good" action feedback. In two types of experimental blocks, the participants performed a gambling task in which they chose one of two cards and received an action feedback that indicated monetary gain or loss. In fixed blocks, the time interval between the participant's choice and the onset of the action feedback was fixed at 0, 500, or 1,000 ms in separate blocks; thus, the timing of action feedback was predictable. In mixed blocks, the time interval was randomly chosen from the same three intervals with equal probability; thus, the timing was less predictable. The results showed that the FRN/RewP was smaller in mixed than fixed blocks for the 0-ms interval trial, whereas there was no difference between the two block types for the 500-ms and 1,000-ms interval trials. Interestingly, the smaller FRN/RewP was due to the modulation of gain ERPs rather than loss ERPs. These results suggest that temporal prediction can modulate the evaluative processing of action feedback, and particularly good feedback, such as that which indicates monetary gain. PMID:27412662

  16. The contribution of surprise to the prediction based modulation of fMRI responses.

    PubMed

    Amado, Catarina; Hermann, Petra; Kovács, Petra; Grotheer, Mareike; Vidnyánszky, Zoltán; Kovács, Gyula

    2016-04-01

    In recent years, several functional magnetic resonance imaging (fMRI) studies showed that correct stimulus predictions reduce the neural responses when compared to surprising events (Egner et al., 2010). Further, it has been shown that such fulfilled expectations enhance the magnitude of repetition suppression (RS, i.e. a decreased neuronal response after the repetition of a given stimulus) in face selective visual cortex as well (Summerfield et al., 2008). Current MEG and neuroimaging studies suggest that the underlying mechanisms of expectation effects are independent from these of RS (Grotheer and Kovács, 2015; Todorovic and Lange, 2012). However, it is not clear as of today how perceptual expectations modulate the neural responses: is the difference between correctly predicted and surprising stimuli due to a genuine response reduction for correctly predicted stimuli or is it due to an increased response for surprising stimuli? Therefore, here we used a modified version of the paradigm of Grotheer and Kovács (2015) to induce predictions independently from repetition probability by presenting pairs of faces (female, male or infant) that were either repeated or alternating. Orthogonally to this, predictions were manipulated by the gender of the first face within each pair so that it signaled high, low or equal probability of repetitions. An unpredicted, neutral condition with equal probabilities for alternating and repeated trials was used to identify the role of surprising and enhancing modulations. Similarly, to Grotheer and Kovács (2015), we found significant RS and significant expectation effect in the FFA. Importantly, we observed larger response for surprising events in comparison to the neutral and correctly predicted conditions for alternating trials. Altogether, these results emphasize the role of surprise in prediction effects. PMID:26873275

  17. A predictive analytic model for the solar modulation of cosmic rays

    DOE PAGES

    Cholis, Ilias; Hooper, Dan; Linden, Tim

    2016-02-23

    An important factor limiting our ability to understand the production and propagation of cosmic rays pertains to the effects of heliospheric forces, commonly known as solar modulation. The solar wind is capable of generating time- and charge-dependent effects on the spectrum and intensity of low-energy (≲10 GeV) cosmic rays reaching Earth. Previous analytic treatments of solar modulation have utilized the force-field approximation, in which a simple potential is adopted whose amplitude is selected to best fit the cosmic-ray data taken over a given period of time. Making use of recently available cosmic-ray data from the Voyager 1 spacecraft, along withmore » measurements of the heliospheric magnetic field and solar wind, we construct a time-, charge- and rigidity-dependent model of solar modulation that can be directly compared to data from a variety of cosmic-ray experiments. Here, we provide a simple analytic formula that can be easily utilized in a variety of applications, allowing us to better predict the effects of solar modulation and reduce the number of free parameters involved in cosmic-ray propagation models.« less

  18. Validation of Skeletal Muscle cis-Regulatory Module Predictions Reveals Nucleotide Composition Bias in Functional Enhancers

    PubMed Central

    Kwon, Andrew T.; Chou, Alice Yi; Arenillas, David J.; Wasserman, Wyeth W.

    2011-01-01

    We performed a genome-wide scan for muscle-specific cis-regulatory modules (CRMs) using three computational prediction programs. Based on the predictions, 339 candidate CRMs were tested in cell culture with NIH3T3 fibroblasts and C2C12 myoblasts for capacity to direct selective reporter gene expression to differentiated C2C12 myotubes. A subset of 19 CRMs validated as functional in the assay. The rate of predictive success reveals striking limitations of computational regulatory sequence analysis methods for CRM discovery. Motif-based methods performed no better than predictions based only on sequence conservation. Analysis of the properties of the functional sequences relative to inactive sequences identifies nucleotide sequence composition can be an important characteristic to incorporate in future methods for improved predictive specificity. Muscle-related TFBSs predicted within the functional sequences display greater sequence conservation than non-TFBS flanking regions. Comparison with recent MyoD and histone modification ChIP-Seq data supports the validity of the functional regions. PMID:22144875

  19. To What Extent Do Joint Attention, Imitation, and Object Play Behaviors in Infancy Predict Later Communication and Intellectual Functioning in ASD?

    ERIC Educational Resources Information Center

    Poon, Kenneth K.; Watson, Linda R.; Baranek, Grace T.; Poe, Michele D.

    2012-01-01

    The extent to which early social communication behaviors predict later communication and intellectual outcomes was investigated via retrospective video analysis. Joint attention, imitation, and complex object play behaviors were coded from edited home videos featuring scenes of 29 children with ASD at 9-12 and/or 15-18 months. A quantitative…

  20. Characteristics of Students at Risk for Mathematics Difficulties Predicting Arithmetic Word Problem Solving Performance: The Role of Attention, Behavior, and Reading

    ERIC Educational Resources Information Center

    Jitendra, Asha K.; Corroy, Kelly Cozine; Dupuis, Danielle N.

    2013-01-01

    The purposes of this study were (a) to evaluate differences in arithmetic word problem solving between high and low at-risk students for mathematics difficulties (MD) and (b) to assess the influence of attention, behavior, reading, and socio-economic status (SES) in predicting the word problem solving performance of third-grade students with MD.…

  1. Theory of Planned Behavior Predicts Graduation Intentions of Canadian and Israeli Postsecondary Students with and without Learning Disabilities/Attention Deficit Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Fichten, Catherine S.; Heiman, Tali; Jorgensen, Mary; Nguyen, Mai Nhu; Havel, Alice; King, Laura; Budd, Jillian; Amsel, Rhonda

    2016-01-01

    We tested the ability of Ajzen's Theory of Planned Behavior (TPB) model to predict intention to graduate among Canadian and Israeli students with and without a learning disability/attention deficit hyperactivity disorder (LD/ADHD). Results based on 1486 postsecondary students show that the model's predictors (i.e., attitude, subjective norms,…

  2. Individual differences in visual field shape modulate the effects of attention on the lower visual field advantage in crowding.

    PubMed

    Fortenbaugh, Francesca C; Silver, Michael A; Robertson, Lynn C

    2015-02-12

    It has previously been reported that visual crowding of a target by flankers is stronger in the upper visual field than in the lower, and this finding has been attributed to greater attentional resolution in the lower hemifield (He, Cavanagh, & Intriligator, 1996). Here we show that the upper/lower asymmetry in visual crowding can be explained by natural variations in the borders of each individual's visual field. Specifically, asymmetry in crowding along the vertical meridian can be almost entirely accounted for by replacing the conventional definition of visual field location, in units of degrees of visual angle, with a definition based on the ratio of the extents of an individual's upper and lower visual field. We also show that the upper/lower crowding asymmetry is eliminated when stimulus eccentricity is expressed in units of percentage of visual field extent but is present when the conventional measure of visual angle is used. We further demonstrate that the relationship between visual field extent and perceptual asymmetry is most evident when participants are able to focus their attention on the target location. These results reveal important influences of visual field boundaries on visual perception, even for visual field locations far from those boundaries.

  3. Modulating rest-break length induces differential recruitment of automatic and controlled attentional processes upon task reengagement.

    PubMed

    Lim, Julian; Teng, James; Wong, Kian Foong; Chee, Michael W L

    2016-07-01

    Rest breaks are commonly administered as a countermeasure to reduce on-the-job fatigue, both physical and mental. However, this practice makes the assumption that recovery from fatigue, as measured by the reversal of performance declines, is the sole effect of taking a break on behavior. Here, through administering rest breaks of differing lengths in between blocks of a mentally demanding symbol decoding task, we show that this assumption may not be strictly true. First, we replicate previous work by showing that taking a longer break leads to two correlated effects: greater immediate rebound in performance, and greater subsequent time-on-task decline. Using fMRI, we reveal that time-on-task in this paradigm is associated with increasing recruitment of fronto-parietal areas associated with top-down control, and decreasing deactivation in the default-mode network. Finally, by analyzing individual differences, we reveal a potential neural basis for our behavioral observation: greater recovery following long breaks is associated with greater activity in the putamen, an area associated with the automatic generation of motor responses, followed by greater activity in left middle frontal gyrus by the end of those task periods. Taken together, this suggests a shift in the implicit engagement of automatic and controlled attentional processing following longer breaks. This shift may be undesirable or detrimental in real-world situations where maintaining a stable level of attention over time is necessary. PMID:27039697

  4. CSI feedback-based CS for underwater acoustic adaptive modulation OFDM system with channel prediction

    NASA Astrophysics Data System (ADS)

    Kuai, Xiao-yan; Sun, Hai-xin; Qi, Jie; Cheng, En; Xu, Xiao-ka; Guo, Yu-hui; Chen, You-gan

    2014-06-01

    In this paper, we investigate the performance of adaptive modulation (AM) orthogonal frequency division multiplexing (OFDM) system in underwater acoustic (UWA) communications. The aim is to solve the problem of large feedback overhead for channel state information (CSI) in every subcarrier. A novel CSI feedback scheme is proposed based on the theory of compressed sensing (CS). We propose a feedback from the receiver that only feedback the sparse channel parameters. Additionally, prediction of the channel state is proposed every several symbols to realize the AM in practice. We describe a linear channel prediction algorithm which is used in adaptive transmission. This system has been tested in the real underwater acoustic channel. The linear channel prediction makes the AM transmission techniques more feasible for acoustic channel communications. The simulation and experiment show that significant improvements can be obtained both in bit error rate (BER) and throughput in the AM scheme compared with the fixed Quadrature Phase Shift Keying (QPSK) modulation scheme. Moreover, the performance with standard CS outperforms the Discrete Cosine Transform (DCT) method.

  5. The M1 Muscarinic Positive Allosteric Modulator PQCA Improves Performance on Translatable Tests of Memory and Attention in Rhesus Monkeys.

    PubMed

    Lange, Henry S; Cannon, Christopher E; Drott, Jason T; Kuduk, Scott D; Uslaner, Jason M

    2015-12-01

    Improved treatment of Alzheimer disease (AD) is a significant unmet medical need that is becoming even more critical given the rise in the number of patients and the substantial economic burden. The current standards of care, acetylcholinesterase inhibitors (AChEIs), are hindered by gastrointestinal side effects owing to their nonselective activation of muscarinic and nicotinic receptors. Recently, the highly selective M1 positive allosteric modulator PQCA (1-((4-cyano-4-(pyridine-2-yl)piperidin-1-yl)methyl-4-oxo-4 H-quinolizine-3-carboxylic acid) has been demonstrated to improve cognition in a variety of rodent and nonhuman primate cognition models without producing significant gastrointestinal side effects. Here we describe the effect of PQCA and the AChEI donepezil on two clinically relevant and highly translatable touchscreen cognition tasks in nonhuman primates: paired-associates learning (PAL) and the continuous-performance task (CPT). Blockade of muscarinic signaling by scopolamine produced significant impairments in both PAL and CPT. PQCA and donepezil attenuated the scopolamine deficits in both tasks, and the action of these two compounds was similar in magnitude. In addition, the combination of subeffective doses of PQCA and donepezil enhanced PAL performance. These results further suggest that M1-positive allosteric modulators, either as monotherapy or as an add-on to current standards of care, have potential to reduce the cognitive deficits associated with AD. PMID:26446308

  6. Looking you in the mouth: abnormal gaze in autism resulting from impaired top-down modulation of visual attention.

    PubMed

    Neumann, Dirk; Spezio, Michael L; Piven, Joseph; Adolphs, Ralph

    2006-12-01

    People with autism are impaired in their social behavior, including their eye contact with others, but the processes that underlie this impairment remain elusive. We combined high-resolution eye tracking with computational modeling in a group of 10 high-functioning individuals with autism to address this issue. The group fixated the location of the mouth in facial expressions more than did matched controls, even when the mouth was not shown, even in faces that were inverted and most noticeably at latencies of 200-400 ms. Comparisons with a computational model of visual saliency argue that the abnormal bias for fixating the mouth in autism is not driven by an exaggerated sensitivity to the bottom-up saliency of the features, but rather by an abnormal top-down strategy for allocating visual attention.

  7. Attention Stabilizes Representations in the Human Hippocampus.

    PubMed

    Aly, Mariam; Turk-Browne, Nicholas B

    2016-02-01

    Attention and memory are intricately linked, but how attention modulates brain areas that subserve memory, such as the hippocampus, is unknown. We hypothesized that attention may stabilize patterns of activity in human hippocampus, resulting in distinct but reliable activity patterns for different attentional states. To test this prediction, we utilized high-resolution functional magnetic resonance imaging and a novel "art gallery" task. On each trial, participants viewed a room containing a painting, and searched a stream of rooms for a painting from the same artist (art state) or a room with the same layout (room state). Bottom-up stimulation was the same in both tasks, enabling the isolation of neural effects related to top-down attention. Multivariate analyses revealed greater pattern similarity in all hippocampal subfields for trials from the same, compared with different, attentional state. This stability was greater for the room than art state, was unrelated to univariate activity, and, in CA2/CA3/DG, was correlated with behavior. Attention therefore induces representational stability in the human hippocampus, resulting in distinct activity patterns for different attentional states. Modulation of hippocampal representational stability highlights the far-reaching influence of attention outside of sensory systems.

  8. Simple tool for prediction of parotid gland sparing in intensity-modulated radiation therapy

    SciTech Connect

    Gensheimer, Michael F.; Hummel-Kramer, Sharon M.; Cain, David; Quang, Tony S.

    2015-10-01

    Sparing one or both parotid glands is a key goal when planning head and neck cancer radiation treatment. If the planning target volume (PTV) overlaps one or both parotid glands substantially, it may not be possible to achieve adequate gland sparing. This finding results in physicians revising their PTV contours after an intensity-modulated radiation therapy (IMRT) plan has been run and reduces workflow efficiency. We devised a simple formula for predicting mean parotid gland dose from the overlap of the parotid gland and isotropically expanded PTV contours. We tested the tool using 44 patients from 2 institutions and found agreement between predicted and actual parotid gland doses (mean absolute error = 5.3 Gy). This simple method could increase treatment planning efficiency by improving the chance that the first plan presented to the physician will have optimal parotid gland sparing.

  9. Alignment and prediction of cis-regulatory modules based on a probabilistic model of evolution.

    PubMed

    He, Xin; Ling, Xu; Sinha, Saurabh

    2009-03-01

    Cross-species comparison has emerged as a powerful paradigm for predicting cis-regulatory modules (CRMs) and understanding their evolution. The comparison requires reliable sequence alignment, which remains a challenging task for less conserved noncoding sequences. Furthermore, the existing models of DNA sequence evolution generally do not explicitly treat the special properties of CRM sequences. To address these limitations, we propose a model of CRM evolution that captures different modes of evolution of functional transcription factor binding sites (TFBSs) and the background sequences. A particularly novel aspect of our work is a probabilistic model of gains and losses of TFBSs, a process being recognized as an important part of regulatory sequence evolution. We present a computational framework that uses this model to solve the problems of CRM alignment and prediction. Our alignment method is similar to existing methods of statistical alignment but uses the conserved binding sites to improve alignment. Our CRM prediction method deals with the inherent uncertainties of binding site annotations and sequence alignment in a probabilistic framework. In simulated as well as real data, we demonstrate that our program is able to improve both alignment and prediction of CRM sequences over several state-of-the-art methods. Finally, we used alignments produced by our program to study binding site conservation in genome-wide binding data of key transcription factors in the Drosophila blastoderm, with two intriguing results: (i) the factor-bound sequences are under strong evolutionary constraints even if their neighboring genes are not expressed in the blastoderm and (ii) binding sites in distal bound sequences (relative to transcription start sites) tend to be more conserved than those in proximal regions. Our approach is implemented as software, EMMA (Evolutionary Model-based cis-regulatory Module Analysis), ready to be applied in a broad biological context.

  10. Analytic IMRT dose calculations utilizing Monte Carlo to predict MLC fluence modulation

    SciTech Connect

    Mihaylov, I.B.; Lerma, F.A.; Wu, Y.; Siebers, J.V.

    2006-04-15

    A hybrid dose-computation method is designed which accurately accounts for multileaf collimator (MLC)-induced intensity modulation in intensity modulated radiation therapy (IMRT) dose calculations. The method employs Monte Carlo (MC) modeling to determine the fluence modulation caused by the delivery of dynamic or multisegmental (step-and-shoot) MLC fields, and a conventional dose-computation algorithm to estimate the delivered dose to a phantom or a patient. Thus, it determines the IMRT fluence prediction accuracy achievable by analytic methods in the limit that the analytic method includes all details of the MLC leaf transport and scatter. The hybrid method is validated and benchmarked by comparison with in-phantom film dose measurements, as well as dose calculations from two in-house, and two commercial treatment planning system analytic fluence estimation methods. All computation methods utilize the same dose algorithm to calculate dose to a phantom, varying only in the estimation of the MLC modulation of the incident photon energy fluence. Gamma analysis, with respect to measured two-dimensional (2D) dose planes, is used to benchmark each algorithm's performance. The analyzed fields include static and dynamic test patterns, as well as fields from ten DMLC IMRT treatment plans (79 fields) and five SMLC treatment plans (29 fields). The test fields (fully closed MLC, picket fence, sliding windows of different size, and leaf-tip profiles) cover the extremes of MLC usage during IMRT, while the patient fields represent realistic clinical conditions. Of the methods tested, the hybrid method most accurately reproduces measurements. For the hybrid method, 79 of 79 DMLC field calculations have {gamma}{<=}1 (3%/3 mm) for more than 95% of the points (per field) while for SMLC fields, 27 of 29 pass the same criteria. The analytic energy fluence estimation methods show inferior pass rates, with 76 of 79 DMLC and 24 of 29 SMLC fields having more than 95% of the test points

  11. The value of immune modulating parameters in predicting the progression from peritonitis to septic shock.

    PubMed

    Katja, B; Hartmut, K; Pawel, M; Stefan, B; Kox, W J; Spies, C D

    2001-02-01

    Intra-abdominal infection is one of the major causes of septic shock and multiple organ failure. To date, what causes the disease's progression remains unclear and therefore the relevance of immune modulating therapies remains speculative. The primary outcome measure of this study was to investigate immune modulating mediators at the onset of peritonitis before the development of subsequent septic shock. The secondary outcome measure was to investigate the usefulness of these immune parameters in predicting progression from peritonitis to septic shock. Fifty-eight peritonitis patients were included in this study: 14 patients subsequently developed septic shock. All patients were examined on "diagnosis of peritonitis" (<4 h within establishment of diagnosis), during "early septic shock" (<12 h following the onset of septic shock), and once again during "late septic shock" (within 72-98 h following the onset of septic shock). The immune modulating parameters tumor necrosis factor-alpha (TNF-alpha), the soluble TNF-alpha receptors I and II (sTNF-alpha RI and sTNF-alpha RII), interleukines (IL) -1beta, -6, -8, and -10, and the adhesions molecules endothelial-leukocyte-adhesion-molecule (E-Selectin), intercellular-adhesion-molecule-1 (ICAM-1), and vascular-adhesion-molecule-1 (VCAM-1), in addition to nitrate and nitrite, were determined. In the peritonitis group with subsequent septic shock, TNF-alpha, sTNF-alpha RI + RII IL-1beta, IL-8, IL-10, and nitrate were significantly increased before the onset of septic shock. TNF-alpha had an area under the receiver operating characteristics curve (AUC) of 0.84 and was reliable in predicting the progression from peritonitis to septic shock. The AUC of the other immune modulating parameters, despite being significantly elevated, ranged from 0.71 to 0.76. The AUC of the conventional laboratory markers such as leukocytes and C-reactive protein ranged from 0.64 to 0.68. In peritonitis that progressed to septic shock, an early

  12. Identification of cancer cytotoxic modulators of PDE3A by predictive chemogenomics

    PubMed Central

    de Waal, Luc; Lewis, Timothy A.; Rees, Matthew G.; Tsherniak, Aviad; Wu, Xiaoyun; Choi, Peter S.; Gechijian, Lara; Hartigan, Christina; Faloon, Patrick W.; Hickey, Mark J.; Tolliday, Nicola; Carr, Steven A.; Clemons, Paul A.; Munoz, Benito; Wagner, Bridget K.; Shamji, Alykhan F.; Koehler, Angela N.; Schenone, Monica; Burgin, Alex B.; Schreiber, Stuart L.; Greulich, Heidi; Meyerson, Matthew

    2015-01-01

    High cancer death rates indicate the need for new anti-cancer therapeutic agents. Approaches to discover new cancer drugs include target-based drug discovery and phenotypic screening. Here, we identified phosphodiesterase 3A modulators as cell-selective cancer cytotoxic compounds by phenotypic compound library screening and target deconvolution by predictive chemogenomics. We found that sensitivity to 6-(4-(diethylamino)-3-nitrophenyl)-5-methyl-4,5-dihydropyridazin-3(2H)-one, or DNMDP, across 766 cancer cell lines correlates with expression of the phosphodiesterase 3A gene, PDE3A. Like DNMDP, a subset of known PDE3A inhibitors kill selected cancer cells while others do not. Furthermore, PDE3A depletion leads to DNMDP resistance. We demonstrated that DNMDP binding to PDE3A promotes an interaction between PDE3A and Schlafen 12 (SLFN12), suggesting a neomorphic activity. Co-expression of SLFN12 with PDE3A correlates with DNMDP sensitivity, while depletion of SLFN12 results in decreased DNMDP sensitivity. Our results implicate PDE3A modulators as candidate cancer therapeutic agents and demonstrate the power of predictive chemogenomics in small-molecule discovery. PMID:26656089

  13. Transdermal flux predictions for selected selective oestrogen receptor modulators (SERMs): comparison with experimental results.

    PubMed

    Güngör, Sevgi; Delgado-Charro, M Begoña; Masini-Etévé, Valérie; Potts, Russell O; Guy, Richard H

    2013-12-28

    The aim of this work was to evaluate the feasibility of delivering transdermally a series of highly lipophilic compounds (log P ~4-7), comprising several selective oestrogen receptor modulators and a modified testosterone (danazol). The maximum fluxes of the drugs were predicted theoretically using the modified Potts & Guy algorithm (to determine the permeability coefficient (kp) from water) and the calculated aqueous solubilities. The correction provided by Cleek & Bunge took into account the contribution of the viable epidermal barrier to the skin permeation of highly lipophilic compounds. Experimental measurements of drug fluxes from saturated hydroalcoholic solutions were determined in vitro through excised pig skin. Overall, the predicted fluxes were in good general agreement (within a factor of 10) with the experimental results. Most of the experimental fluxes were greater than those predicted theoretically suggesting that the 70:30 v/v ethanol-water vehicle employed may have had a modest skin penetration enhancement effect. This investigation shows that the transdermal fluxes of highly lipophilic compounds can be reasonably predicted from first principles provided that the viable epidermis, underlying the stratum corneum, is included as a potentially important contributor to the skin's overall barrier function. Furthermore, the absolute values of the measured fluxes, when considered in parallel with previous clinical studies, indicate that it might be feasible to topically deliver a therapeutically useful amount of some of the compounds considered to treat cancerous breast tissue. PMID:24076520

  14. Transdermal flux predictions for selected selective oestrogen receptor modulators (SERMs): comparison with experimental results.

    PubMed

    Güngör, Sevgi; Delgado-Charro, M Begoña; Masini-Etévé, Valérie; Potts, Russell O; Guy, Richard H

    2013-12-28

    The aim of this work was to evaluate the feasibility of delivering transdermally a series of highly lipophilic compounds (log P ~4-7), comprising several selective oestrogen receptor modulators and a modified testosterone (danazol). The maximum fluxes of the drugs were predicted theoretically using the modified Potts & Guy algorithm (to determine the permeability coefficient (kp) from water) and the calculated aqueous solubilities. The correction provided by Cleek & Bunge took into account the contribution of the viable epidermal barrier to the skin permeation of highly lipophilic compounds. Experimental measurements of drug fluxes from saturated hydroalcoholic solutions were determined in vitro through excised pig skin. Overall, the predicted fluxes were in good general agreement (within a factor of 10) with the experimental results. Most of the experimental fluxes were greater than those predicted theoretically suggesting that the 70:30 v/v ethanol-water vehicle employed may have had a modest skin penetration enhancement effect. This investigation shows that the transdermal fluxes of highly lipophilic compounds can be reasonably predicted from first principles provided that the viable epidermis, underlying the stratum corneum, is included as a potentially important contributor to the skin's overall barrier function. Furthermore, the absolute values of the measured fluxes, when considered in parallel with previous clinical studies, indicate that it might be feasible to topically deliver a therapeutically useful amount of some of the compounds considered to treat cancerous breast tissue.

  15. PETModule: a motif module based approach for enhancer target gene prediction

    PubMed Central

    Zhao, Changyong; Li, Xiaoman; Hu, Haiyan

    2016-01-01

    The identification of enhancer-target gene (ETG) pairs is vital for the understanding of gene transcriptional regulation. Experimental approaches such as Hi-C have generated valuable resources of ETG pairs. Several computational methods have also been developed to successfully predict ETG interactions. Despite these progresses, high-throughput experimental approaches are still costly and existing computational approaches are still suboptimal and not easy to apply. Here we developed a motif module based approach called PETModule that predicts ETG pairs. Tested on eight human cell types and two mouse cell types, we showed that a large number of our predictions were supported by Hi-C and/or ChIA-PET experiments. Compared with two recently developed approaches for ETG pair prediction, we shown that PETModule had a much better recall, a similar or better F1 score, and a larger area under the receiver operating characteristic curve. The PETModule tool is freely available at http://hulab.ucf.edu/research/projects/PETModule/. PMID:27436110

  16. PETModule: a motif module based approach for enhancer target gene prediction.

    PubMed

    Zhao, Changyong; Li, Xiaoman; Hu, Haiyan

    2016-01-01

    The identification of enhancer-target gene (ETG) pairs is vital for the understanding of gene transcriptional regulation. Experimental approaches such as Hi-C have generated valuable resources of ETG pairs. Several computational methods have also been developed to successfully predict ETG interactions. Despite these progresses, high-throughput experimental approaches are still costly and existing computational approaches are still suboptimal and not easy to apply. Here we developed a motif module based approach called PETModule that predicts ETG pairs. Tested on eight human cell types and two mouse cell types, we showed that a large number of our predictions were supported by Hi-C and/or ChIA-PET experiments. Compared with two recently developed approaches for ETG pair prediction, we shown that PETModule had a much better recall, a similar or better F1 score, and a larger area under the receiver operating characteristic curve. The PETModule tool is freely available at http://hulab.ucf.edu/research/projects/PETModule/. PMID:27436110

  17. Predicting deliverability of volumetric-modulated arc therapy (VMAT) plans using aperture complexity analysis.

    PubMed

    Younge, Kelly C; Roberts, Don; Janes, Lindsay A; Anderson, Carlos; Moran, Jean M; Matuszak, Martha M

    2016-07-08

    The purpose of this study was to evaluate the ability of an aperture complexity metric for volumetric-modulated arc therapy (VMAT) plans to predict plan delivery accuracy. We developed a complexity analysis tool as a plug-in script to Varian's Eclipse treatment planning system. This script reports the modulation of plans, arcs, and individual control points for VMAT plans using a previously developed complexity metric. The calculated complexities are compared to that of 649 VMAT plans previously treated at our institution from 2013 to mid-2015. We used the VMAT quality assurance (QA) results from the 649 treated plans, plus 62 plans that failed pretreatment QA, to validate the ability of the complexity metric to predict plan deliverability. We used a receiver operating characteristic (ROC) analysis to determine an appropriate complexity threshold value above which a plan should be considered for reoptimization before it moves further through our planning workflow. The average complexity metric for the 649 treated plans analyzed with the script was 0.132 mm-1 with a standard deviation of 0.036 mm-1. We found that when using a threshold complexity value of 0.180 mm-1, the true positive rate for correctly identifying plans that failed QA was 44%, and the false-positive rate was 7%. Used clinically with this threshold, the script can identify overly modulated plans and thus prevent a significant portion of QA failures. Reducing VMAT plan complexity has a number of important clinical benefits, including improving plan deliverability and reducing treatment time. Use of the complexity metric during both the planning and QA processes can reduce the number of QA failures and improve the quality of VMAT plans used for treatment.

  18. Endocannabinoid-Dependent Modulation of Phasic Dopamine Signaling Encodes External and Internal Reward-Predictive Cues

    PubMed Central

    Wenzel, Jennifer M.; Cheer, Joseph F.

    2014-01-01

    The mesolimbic dopamine (DA) system plays an integral role in incentive motivation and reward seeking and a growing body of evidence identifies signal transduction at cannabinoid receptors as a critical modulator of this system. Indeed, administration of exogenous cannabinoids results in burst firing of DA neurons of the ventral tegmental area and increases extracellular DA in the nucleus accumbens (NAcc). Implementation of fast-scan cyclic voltammetry (FSCV) confirms the ability of cannabinoids to augment DA within the NAcc on a subsecond timescale. The use of FSCV along with newly developed highly selective pharmacological compounds advances our understanding of how cannabinoids influence DA transmission and highlights a role for endocannabinoid-modulated subsecond DAergic activation in the incentive motivational properties of not only external, but also internal reward-predictive cues. For example, our laboratory has recently demonstrated that in mice responding under a fixed-interval (FI) schedule for food reinforcement, fluctuations in NAcc DA signal the principal cue predictive of reinforcer availability – time. That is, as the interval progresses, NAcc DA levels decline leading to accelerated food seeking and the resulting characteristic FI scallop pattern of responding. Importantly, administration of WIN 55,212-2, a synthetic cannabinoid agonist, or JZL184, an indirect cannabinoid agonist, increases DA levels during the interval and disrupts this pattern of responding. Along with a wealth of other reports, these results illustrate the role of cannabinoid receptor activation in the regulation of DA transmission and the control of temporally guided reward seeking. The current review will explore the striatal beat frequency model of interval timing as it pertains to cannabinoid signaling and propose a neurocircuitry through which this system modulates interoceptive time cues. PMID:25225488

  19. Endocannabinoid-dependent modulation of phasic dopamine signaling encodes external and internal reward-predictive cues.

    PubMed

    Wenzel, Jennifer M; Cheer, Joseph F

    2014-01-01

    The mesolimbic dopamine (DA) system plays an integral role in incentive motivation and reward seeking and a growing body of evidence identifies signal transduction at cannabinoid receptors as a critical modulator of this system. Indeed, administration of exogenous cannabinoids results in burst firing of DA neurons of the ventral tegmental area and increases extracellular DA in the nucleus accumbens (NAcc). Implementation of fast-scan cyclic voltammetry (FSCV) confirms the ability of cannabinoids to augment DA within the NAcc on a subsecond timescale. The use of FSCV along with newly developed highly selective pharmacological compounds advances our understanding of how cannabinoids influence DA transmission and highlights a role for endocannabinoid-modulated subsecond DAergic activation in the incentive motivational properties of not only external, but also internal reward-predictive cues. For example, our laboratory has recently demonstrated that in mice responding under a fixed-interval (FI) schedule for food reinforcement, fluctuations in NAcc DA signal the principal cue predictive of reinforcer availability - time. That is, as the interval progresses, NAcc DA levels decline leading to accelerated food seeking and the resulting characteristic FI scallop pattern of responding. Importantly, administration of WIN 55,212-2, a synthetic cannabinoid agonist, or JZL184, an indirect cannabinoid agonist, increases DA levels during the interval and disrupts this pattern of responding. Along with a wealth of other reports, these results illustrate the role of cannabinoid receptor activation in the regulation of DA transmission and the control of temporally guided reward seeking. The current review will explore the striatal beat frequency model of interval timing as it pertains to cannabinoid signaling and propose a neurocircuitry through which this system modulates interoceptive time cues. PMID:25225488

  20. Endocannabinoid-dependent modulation of phasic dopamine signaling encodes external and internal reward-predictive cues.

    PubMed

    Wenzel, Jennifer M; Cheer, Joseph F

    2014-01-01

    The mesolimbic dopamine (DA) system plays an integral role in incentive motivation and reward seeking and a growing body of evidence identifies signal transduction at cannabinoid receptors as a critical modulator of this system. Indeed, administration of exogenous cannabinoids results in burst firing of DA neurons of the ventral tegmental area and increases extracellular DA in the nucleus accumbens (NAcc). Implementation of fast-scan cyclic voltammetry (FSCV) confirms the ability of cannabinoids to augment DA within the NAcc on a subsecond timescale. The use of FSCV along with newly developed highly selective pharmacological compounds advances our understanding of how cannabinoids influence DA transmission and highlights a role for endocannabinoid-modulated subsecond DAergic activation in the incentive motivational properties of not only external, but also internal reward-predictive cues. For example, our laboratory has recently demonstrated that in mice responding under a fixed-interval (FI) schedule for food reinforcement, fluctuations in NAcc DA signal the principal cue predictive of reinforcer availability - time. That is, as the interval progresses, NAcc DA levels decline leading to accelerated food seeking and the resulting characteristic FI scallop pattern of responding. Importantly, administration of WIN 55,212-2, a synthetic cannabinoid agonist, or JZL184, an indirect cannabinoid agonist, increases DA levels during the interval and disrupts this pattern of responding. Along with a wealth of other reports, these results illustrate the role of cannabinoid receptor activation in the regulation of DA transmission and the control of temporally guided reward seeking. The current review will explore the striatal beat frequency model of interval timing as it pertains to cannabinoid signaling and propose a neurocircuitry through which this system modulates interoceptive time cues.

  1. Predictive Validity of a Continuous Alternative to Nominal Subtypes of Attention-Deficit/Hyperactivity Disorder for "DSM-V"

    ERIC Educational Resources Information Center

    Lahey, Benjamin B.; Willcutt, Erik G.

    2010-01-01

    Three subtypes of attention-deficit/hyperactivity disorder (ADHD) based on numbers of symptoms of inattention (I) and hyperactivity-impulsivity (HI) were defined in the "Diagnostic and Statistical Manual of Mental Disorders" (4th ed.) to reduce heterogeneity of the disorder, but the subtypes proved to be highly unstable over time. A continuous…

  2. Predictive Power of Attention and Reading Readiness Variables on Auditory Reasoning and Processing Skills of Six-Year-Old Children

    ERIC Educational Resources Information Center

    Erbay, Filiz

    2013-01-01

    The aim of present research was to describe the relation of six-year-old children's attention and reading readiness skills (general knowledge, word comprehension, sentences, and matching) with their auditory reasoning and processing skills. This was a quantitative study based on scanning model. Research sampling consisted of 204 kindergarten…

  3. Predicting invasive species impacts: a community module functional response approach reveals context dependencies.

    PubMed

    Paterson, Rachel A; Dick, Jaimie T A; Pritchard, Daniel W; Ennis, Marilyn; Hatcher, Melanie J; Dunn, Alison M

    2015-03-01

    Predatory functional responses play integral roles in predator-prey dynamics, and their assessment promises greater understanding and prediction of the predatory impacts of invasive species. Other interspecific interactions, however, such as parasitism and higher-order predation, have the potential to modify predator-prey interactions and thus the predictive capability of the comparative functional response approach. We used a four-species community module (higher-order predator; focal native or invasive predators; parasites of focal predators; native prey) to compare the predatory functional responses of native Gammarus duebeni celticus and invasive Gammarus pulex amphipods towards three invertebrate prey species (Asellus aquaticus, Simulium spp., Baetis rhodani), thus, quantifying the context dependencies of parasitism and a higher-order fish predator on these functional responses. Our functional response experiments demonstrated that the invasive amphipod had a higher predatory impact (lower handling time) on two of three prey species, which reflects patterns of impact observed in the field. The community module also revealed that parasitism had context-dependent influences, for one prey species, with the potential to further reduce the predatory impact of the invasive amphipod or increase the predatory impact of the native amphipod in the presence of a higher-order fish predator. Partial consumption of prey was similar for both predators and occurred increasingly in the order A. aquaticus, Simulium spp. and B. rhodani. This was associated with increasing prey densities, but showed no context dependencies with parasitism or higher-order fish predator. This study supports the applicability of comparative functional responses as a tool to predict and assess invasive species impacts incorporating multiple context dependencies.

  4. Predicting invasive species impacts: a community module functional response approach reveals context dependencies.

    PubMed

    Paterson, Rachel A; Dick, Jaimie T A; Pritchard, Daniel W; Ennis, Marilyn; Hatcher, Melanie J; Dunn, Alison M

    2015-03-01

    Predatory functional responses play integral roles in predator-prey dynamics, and their assessment promises greater understanding and prediction of the predatory impacts of invasive species. Other interspecific interactions, however, such as parasitism and higher-order predation, have the potential to modify predator-prey interactions and thus the predictive capability of the comparative functional response approach. We used a four-species community module (higher-order predator; focal native or invasive predators; parasites of focal predators; native prey) to compare the predatory functional responses of native Gammarus duebeni celticus and invasive Gammarus pulex amphipods towards three invertebrate prey species (Asellus aquaticus, Simulium spp., Baetis rhodani), thus, quantifying the context dependencies of parasitism and a higher-order fish predator on these functional responses. Our functional response experiments demonstrated that the invasive amphipod had a higher predatory impact (lower handling time) on two of three prey species, which reflects patterns of impact observed in the field. The community module also revealed that parasitism had context-dependent influences, for one prey species, with the potential to further reduce the predatory impact of the invasive amphipod or increase the predatory impact of the native amphipod in the presence of a higher-order fish predator. Partial consumption of prey was similar for both predators and occurred increasingly in the order A. aquaticus, Simulium spp. and B. rhodani. This was associated with increasing prey densities, but showed no context dependencies with parasitism or higher-order fish predator. This study supports the applicability of comparative functional responses as a tool to predict and assess invasive species impacts incorporating multiple context dependencies. PMID:25265905

  5. Predicting invasive species impacts: a community module functional response approach reveals context dependencies

    PubMed Central

    Paterson, Rachel A; Dick, Jaimie T A; Pritchard, Daniel W; Ennis, Marilyn; Hatcher, Melanie J; Dunn, Alison M

    2015-01-01

    Summary Predatory functional responses play integral roles in predator–prey dynamics, and their assessment promises greater understanding and prediction of the predatory impacts of invasive species. Other interspecific interactions, however, such as parasitism and higher-order predation, have the potential to modify predator–prey interactions and thus the predictive capability of the comparative functional response approach. We used a four-species community module (higher-order predator; focal native or invasive predators; parasites of focal predators; native prey) to compare the predatory functional responses of native Gammarus duebeni celticus and invasive Gammarus pulex amphipods towards three invertebrate prey species (Asellus aquaticus, Simulium spp., Baetis rhodani), thus, quantifying the context dependencies of parasitism and a higher-order fish predator on these functional responses. Our functional response experiments demonstrated that the invasive amphipod had a higher predatory impact (lower handling time) on two of three prey species, which reflects patterns of impact observed in the field. The community module also revealed that parasitism had context-dependent influences, for one prey species, with the potential to further reduce the predatory impact of the invasive amphipod or increase the predatory impact of the native amphipod in the presence of a higher-order fish predator. Partial consumption of prey was similar for both predators and occurred increasingly in the order A. aquaticus, Simulium spp. and B. rhodani. This was associated with increasing prey densities, but showed no context dependencies with parasitism or higher-order fish predator. This study supports the applicability of comparative functional responses as a tool to predict and assess invasive species impacts incorporating multiple context dependencies. PMID:25265905

  6. Cellular prion protein modulates defensive attention and innate fear-induced behaviour evoked in transgenic mice submitted to an agonistic encounter with the tropical coral snake Oxyrhopus guibei.

    PubMed

    Lobão-Soares, Bruno; Walz, Roger; Prediger, Rui Daniel Schröder; Freitas, Renato Leonardo; Calvo, Fabrício; Bianchin, Marino Muxfeldt; Leite, João Pereira; Landemberger, Michele Christine; Coimbra, Norberto Cysne

    2008-12-12

    The cellular prion protein (PrP(C)) is a neuronal anchored glycoprotein that has been associated with distinct functions in the CNS, such as cellular adhesion and differentiation, synaptic plasticity and cognition. Here we investigated the putative involvement of the PrP(C) in the innate fear-induced behavioural reactions in wild-type (WT), PrP(C) knockout (Prnp(0/0)) and the PrP(C) overexpressing Tg-20 mice evoked in a prey versus predator paradigm. The behavioural performance of these mouse strains in olfactory discrimination tasks was also investigated. When confronted with coral snakes, mice from both Prnp(0/0) and Tg-20 strains presented a significant decrease in frequency and duration of defensive attention and risk assessment, compared to WT mice. Tg-20 mice presented decreased frequency of escape responses, increased exploratory behaviour, and enhancement of interaction with the snake, suggesting a robust fearlessness caused by PrP(C) overexpression. Interestingly, there was also a discrete decrease in the attentional defensive response (decreased frequency of defensive alertness) in Prnp(0/0) mice in the presence of coral snakes. Moreover, Tg-20 mice presented an increased exploration of novel environment and odors. The present findings indicate that the PrP(C) overexpression causes hyperactivity, fearlessness, and increased preference for visual, tactile and olfactory stimuli-associated novelty, and that the PrP(c) deficiency might lead to attention deficits. These results suggest that PrP(c) exerts an important role in the modulation of innate fear and novelty-induced exploration.

  7. Modulation of the default-mode network and the attentional network by self-referential processes in patients with disorder of consciousness.

    PubMed

    Mäki-Marttunen, Verónica; Castro, Mariana; Olmos, Lisandro; Leiguarda, Ramón; Villarreal, Mirta

    2016-02-01

    Disorders of consciousness (DOC) are related to an altered capacity of the brain to successfully integrate and segregate information. Alterations in brain functional networks structure have been found in fMRI studies, which could account for the incapability of the brain to efficiently manage internally and externally generated information. Here we assess the modulation of neural activity in areas of the networks related to active introspective or extrospective processing in 9 patients with DOC and 17 controls using fMRI. In addition, we assess the functional connectivity between those areas in resting state. Patients were experimentally studied in an early phase after the event of brain injury (3±1 months after the event) and subsequently in a second session 4±1 months after the first session. The results showed that the concerted modulation of the default mode network (DMN) and attentional network (AN) in response to the active involvement in the task improved with the level of consciousness, reflecting an integral recovery of the brain in its ability to be engaged in cognitive processes. In addition, functional connectivity decreased between the DMN and AN with recovery. Our results help to further understand the neural underpins of the disorders of consciousness. PMID:26796715

  8. Plant intelligence and attention

    PubMed Central

    Marder, Michael

    2013-01-01

    This article applies the phenomenological model of attention to plant monitoring of environmental stimuli and signal perception. Three complementary definitions of attention as selectivity, modulation and perdurance are explained with reference to plant signaling and behaviors, including foraging, ramet placement and abiotic stress communication. Elements of animal and human attentive attitudes are compared with plant attention at the levels of cognitive focus, context and margin. It is argued that the concept of attention holds the potential of becoming a cornerstone of plant intelligence studies. PMID:23425923

  9. Microbial modulators of soil carbon storage: integrating genomic and metabolic knowledge for global prediction.

    PubMed

    Trivedi, Pankaj; Anderson, Ian C; Singh, Brajesh K

    2013-12-01

    Soil organic carbon performs a number of functions in ecosystems and it is clear that microbial communities play important roles in land-atmosphere carbon (C) exchange and soil C storage. In this review, we discuss microbial modulators of soil C storage, 'omics'-based approaches to characterize microbial system interactions impacting terrestrial C sequestration, and how data related to microbial composition and activities can be incorporated into mechanistic and predictive models. We argue that although making direct linkage of genomes to global phenomena is a significant challenge, many connections at intermediate scales are viable with integrated application of new systems biology approaches and powerful analytical and modelling techniques. This integration could enhance our capability to develop and evaluate microbial strategies for capturing and sequestering atmospheric CO2.

  10. Array Simulations Platform (ASP) predicts NASA Data Link Module (NDLM) performance

    NASA Technical Reports Server (NTRS)

    Snook, Allen David

    1993-01-01

    Through a variety of imbedded theoretical and actual antenna patterns, the array simulation platform (ASP) enhanced analysis of the array antenna pattern effects for the KTx (Ku-Band Transmit) service of the NDLM (NASA Data Link Module). The ASP utilizes internally stored models of the NDLM antennas and can develop the overall pattern of antenna arrays through common array calculation techniques. ASP expertly assisted in the diagnosing of element phase shifter errors during KTx testing and was able to accurately predict the overall array pattern from combinations of the four internally held element patterns. This paper provides an overview of the use of the ASP software in the solving of array mis-phasing problems.

  11. Validation and comparison of three power prediction models for CPV modules

    NASA Astrophysics Data System (ADS)

    Mundel, Hannah; Treiber, Lara; Dufour, Pascal; Coish, Nicholas; Fischer, Anton; Myrskog, Stefan

    2015-09-01

    Accurate predictive energy modelling of a solar farm requires a thorough understanding of solar spectral variations, along with the spectral response and optical properties of the photovoltaic system. This paper investigates the minimum data required to accurately predict power output from CPV modules, comparing modelled output to both measured data and the existing method used by Sandia PV Array Performance Model (SAPM). Three models were derived based on various weather inputs. A Detailed Spectral Model (DS) uses SMARTS, inputting measured air mass, aerosols, ozone and water content, and incorporating measured DNI to account for cloudy days. The Sub-System Algebraic Model (SSA) removes the need for instantaneous spectrum calculations by creating equations for each sub-cell and DNI, based on the same inputs as the DS. These two models rely heavily on aerosol, which is not readily available. Alternatively, an Empirical model (EMP) may be used to determine the relationship between measured output power and easily measureable weather data (ambient temperature, air mass, direct normal irradiance and water content). These non-linear DS, SSA and EMP models have a bias error of 3.09 %, 4.24 % and -0.67 %, respectively. It was also found that the SSA model can be used in lieu of the SAPM.

  12. Predictive Validity of ICD-10 Hyperkinetic Disorder Relative to DSM-IV Attention-Deficit/Hyperactivity Disorder among Younger Children

    ERIC Educational Resources Information Center

    Lahey, Benjamin B.; Pelham, William E.; Chronis, Andrea; Massetti, Greta; Kipp, Heidi; Ehrhardt, Ashley; Lee, Steve S.

    2006-01-01

    Background: Little is known about the predictive validity of hyperkinetic disorder (HKD) as defined by the Diagnostic Criteria for Research for mental and behavioral disorders of the tenth edition of the International Classification of Diseases (ICD-10; World Health Organization, 1993), particularly when the diagnosis is given to younger children.…

  13. Why Does Working Memory Capacity Predict Variation in Reading Comprehension? On the Influence of Mind Wandering and Executive Attention

    ERIC Educational Resources Information Center

    McVay, Jennifer C.; Kane, Michael J.

    2012-01-01

    Some people are better readers than others, and this variation in comprehension ability is predicted by measures of working memory capacity (WMC). The primary goal of this study was to investigate the mediating role of mind-wandering experiences in the association between WMC and normal individual differences in reading comprehension, as predicted…

  14. Mindfulness predicts less texting while driving among young adults: Examining attention- and emotion-regulation motives as potential mediators

    PubMed Central

    Feldman, Greg; Greeson, Jeff; Renna, Megan; Robbins-Monteith, Kendra

    2011-01-01

    Many young adult drivers read and send text messages while driving despite clear safety risks. Understanding predictors of texting-while-driving may help to indentify relevant targets for interventions to reduce this dangerous behavior. The present study examined whether individual differences in mindfulness is associated with texting-while-driving in a sample of young-adult drivers. Using path analysis, we tested whether this relationship would be mediated by the degree to which individuals use text-messaging as a means of reducing unpleasant emotions (emotion-regulation motives) and the degree to which individuals limit texting in order to focus on present-moment experiences (attention-regulation motives). Individuals lower in mindfulness reported more frequent texting-while-driving and this relationship appeared to be mediated primarily by emotion-regulation motives. Results may help inform the development of mindfulness-based interventions to prevent texting-while-driving. PMID:22031789

  15. Pre-attentive sensitivity to vowel duration reveals native phonology and predicts learning of second-language sounds.

    PubMed

    Chládková, Kateřina; Escudero, Paola; Lipski, Silvia C

    2013-09-01

    In some languages (e.g. Czech), changes in vowel duration affect word meaning, while in others (e.g. Spanish) they do not. Yet for other languages (e.g. Dutch), the linguistic role of vowel duration remains unclear. To reveal whether Dutch represents vowel length in its phonology, we compared auditory pre-attentive duration processing in native and non-native vowels across Dutch, Czech, and Spanish. Dutch duration sensitivity patterned with Czech but was larger than Spanish in the native vowel, while it was smaller than Czech and Spanish in the non-native vowel. An interpretation of these findings suggests that in Dutch, duration is used phonemically but it might be relevant for the identity of certain native vowels only. Furthermore, the finding that Spanish listeners are more sensitive to duration in non-native than in native vowels indicates that a lack of duration differences in one's native language could be beneficial for second-language learning.

  16. Attention Alters Perceived Attractiveness.

    PubMed

    Störmer, Viola S; Alvarez, George A

    2016-04-01

    Can attention alter the impression of a face? Previous studies showed that attention modulates the appearance of lower-level visual features. For instance, attention can make a simple stimulus appear to have higher contrast than it actually does. We tested whether attention can also alter the perception of a higher-order property-namely, facial attractiveness. We asked participants to judge the relative attractiveness of two faces after summoning their attention to one of the faces using a briefly presented visual cue. Across trials, participants judged the attended face to be more attractive than the same face when it was unattended. This effect was not due to decision or response biases, but rather was due to changes in perceptual processing of the faces. These results show that attention alters perceived facial attractiveness, and broadly demonstrate that attention can influence higher-level perception and may affect people's initial impressions of one another. PMID:26966228

  17. Not so different after all: The same oscillatory processes support different types of attention.

    PubMed

    Frey, Julia Natascha; Ruhnau, Philipp; Weisz, Nathan

    2015-11-11

    Scientific research from the last two decades has provided a vast amount of evidence that brain oscillations reflect physiological activity enabling diverse cognitive processes. The goal of this review is to give a broad empirical and conceptual overview of how ongoing oscillatory activity may support attention processes. Keeping in mind that definitions of cognitive constructs like attention are prone to being blurry and ambiguous, the present review focuses mainly on the neural correlates of 'top-down' attention deployment. In particular, we will discuss modulations of (ongoing) oscillatory activity during spatial, temporal, selective, and internal attention. Across these seemingly distinct attentional domains, we will summarize studies showing the involvement of two oscillatory processes observed during attention deployment: power modulations mainly in the alpha band, and phase modulations in lower frequency bands. This article is part of a Special Issue entitled SI: Prediction and Attention.

  18. Not so different after all: The same oscillatory processes support different types of attention.

    PubMed

    Frey, Julia Natascha; Ruhnau, Philipp; Weisz, Nathan

    2015-11-11

    Scientific research from the last two decades has provided a vast amount of evidence that brain oscillations reflect physiological activity enabling diverse cognitive processes. The goal of this review is to give a broad empirical and conceptual overview of how ongoing oscillatory activity may support attention processes. Keeping in mind that definitions of cognitive constructs like attention are prone to being blurry and ambiguous, the present review focuses mainly on the neural correlates of 'top-down' attention deployment. In particular, we will discuss modulations of (ongoing) oscillatory activity during spatial, temporal, selective, and internal attention. Across these seemingly distinct attentional domains, we will summarize studies showing the involvement of two oscillatory processes observed during attention deployment: power modulations mainly in the alpha band, and phase modulations in lower frequency bands. This article is part of a Special Issue entitled SI: Prediction and Attention. PMID:25721788

  19. An online trajectory module (version 1.0) for the nonhydrostatic numerical weather prediction model COSMO

    NASA Astrophysics Data System (ADS)

    Miltenberger, A. K.; Pfahl, S.; Wernli, H.

    2013-11-01

    A module to calculate online trajectories has been implemented into the nonhydrostatic limited-area weather prediction and climate model COSMO. Whereas offline trajectories are calculated with wind fields from model output, which is typically available every one to six hours, online trajectories use the simulated resolved wind field at every model time step (typically less than a minute) to solve the trajectory equation. As a consequence, online trajectories much better capture the short-term temporal fluctuations of the wind field, which is particularly important for mesoscale flows near topography and convective clouds, and they do not suffer from temporal interpolation errors between model output times. The numerical implementation of online trajectories in the COSMO-model is based upon an established offline trajectory tool and takes full account of the horizontal domain decomposition that is used for parallelization of the COSMO-model. Although a perfect workload balance cannot be achieved for the trajectory module (due to the fact that trajectory positions are not necessarily equally distributed over the model domain), the additional computational costs are found to be fairly small for the high-resolution simulations described in this paper. The computational costs may, however, vary strongly depending on the number of trajectories and trace variables. Various options have been implemented to initialize online trajectories at different locations and times during the model simulation. As a first application of the new COSMO-model module, an Alpine north foehn event in summer 1987 has been simulated with horizontal resolutions of 2.2, 7 and 14 km. It is shown that low-tropospheric trajectories calculated offline with one- to six-hourly wind fields can significantly deviate from trajectories calculated online. Deviations increase with decreasing model grid spacing and are particularly large in regions of deep convection and strong orographic flow distortion. On

  20. The mGluR2 positive allosteric modulator, SAR218645, improves memory and attention deficits in translational models of cognitive symptoms associated with schizophrenia

    PubMed Central

    Griebel, Guy; Pichat, Philippe; Boulay, Denis; Naimoli, Vanessa; Potestio, Lisa; Featherstone, Robert; Sahni, Sukhveen; Defex, Henry; Desvignes, Christophe; Slowinski, Franck; Vigé, Xavier; Bergis, Olivier E.; Sher, Rosy; Kosley, Raymond; Kongsamut, Sathapana; Black, Mark D.; Varty, Geoffrey B.

    2016-01-01

    Normalization of altered glutamate neurotransmission through activation of the mGluR2 has emerged as a new approach to treat schizophrenia. These studies describe a potent brain penetrant mGluR2 positive allosteric modulator (PAM), SAR218645. The compound behaves as a selective PAM of mGluR2 in recombinant and native receptor expression systems, increasing the affinity of glutamate at mGluR2 as inferred by competition and GTPγ35S binding assays. SAR218645 augmented the mGluR2-mediated response to glutamate in a rat recombinant mGluR2 forced-coupled Ca2+ mobilization assay. SAR218645 potentiated mGluR2 agonist-induced contralateral turning. When SAR218645 was tested in models of the positive symptoms of schizophrenia, it reduced head twitch behavior induced by DOI, but it failed to inhibit conditioned avoidance and hyperactivity using pharmacological and transgenic models. Results from experiments in models of the cognitive symptoms associated with schizophrenia showed that SAR218645 improved MK-801-induced episodic memory deficits in rats and attenuated working memory impairment in NMDA Nr1neo−/− mice. The drug reversed disrupted latent inhibition and auditory-evoked potential in mice and rats, respectively, two endophenotypes of schizophrenia. This profile positions SAR218645 as a promising candidate for the treatment of cognitive symptoms of patients with schizophrenia, in particular those with abnormal attention and sensory gating abilities. PMID:27734956

  1. From the heart to the mind: cardiac vagal tone modulates top-down and bottom-up visual perception and attention to emotional stimuli

    PubMed Central

    Park, Gewnhi; Thayer, Julian F.

    2014-01-01

    The neurovisceral integration model (Thayer and Lane, 2000) posits that cardiac vagal tone, indexed by heart rate variability (HRV), can indicate the functional integrity of the neural networks implicated in emotion–cognition interactions. Our recent findings begin to disentangle how HRV is associated with both top-down and bottom-up cognitive processing of emotional stimuli. Higher resting HRV is associated with more adaptive and functional top-down and bottom-up cognitive modulation of emotional stimuli, which may facilitate effective emotion regulation. Conversely, lower resting HRV is associated with hyper-vigilant and maladaptive cognitive responses to emotional stimuli, which may impede emotion regulation. In the present paper, we recapitulate the neurovisceral integration model and review recent findings that shed light on the relationship between HRV and top-down and bottom-up visual perception and attention to emotional stimuli, which may play an important role in emotion regulation. Further implications of HRV on individual well-being and mental health are discussed. PMID:24817853

  2. Gene expression signature-based chemical genomic prediction identifies a novel class of HSP90 pathway modulators.

    PubMed

    Hieronymus, Haley; Lamb, Justin; Ross, Kenneth N; Peng, Xiao P; Clement, Cristina; Rodina, Anna; Nieto, Maria; Du, Jinyan; Stegmaier, Kimberly; Raj, Srilakshmi M; Maloney, Katherine N; Clardy, Jon; Hahn, William C; Chiosis, Gabriela; Golub, Todd R

    2006-10-01

    Although androgen receptor (AR)-mediated signaling is central to prostate cancer, the ability to modulate AR signaling states is limited. Here we establish a chemical genomic approach for discovery and target prediction of modulators of cancer phenotypes, as exemplified by AR signaling. We first identify AR activation inhibitors, including a group of structurally related compounds comprising celastrol, gedunin, and derivatives. To develop an in silico approach for target pathway identification, we apply a gene expression-based analysis that classifies HSP90 inhibitors as having similar activity to celastrol and gedunin. Validating this prediction, we demonstrate that celastrol and gedunin inhibit HSP90 activity and HSP90 clients, including AR. Broadly, this work identifies new modes of HSP90 modulation through a gene expression-based strategy. PMID:17010675

  3. Identification of cancer-cytotoxic modulators of PDE3A by predictive chemogenomics | Office of Cancer Genomics

    Cancer.gov

    High cancer death rates indicate the need for new anticancer therapeutic agents. Approaches to discovering new cancer drugs include target-based drug discovery and phenotypic screening. Here, we identified phosphodiesterase 3A modulators as cell-selective cancer cytotoxic compounds through phenotypic compound library screening and target deconvolution by predictive chemogenomics.

  4. Prediction of hydrodynamics and chemistry of confined turbulent methane-air flames with attention to formation of oxides of nitrogen

    NASA Technical Reports Server (NTRS)

    Elghobashi, S.; Spalding, D. B.; Srivatsa, S. K.

    1977-01-01

    A formulation of the governing partial differential equations for fluid flow and reacting chemical species in a tubular combustor is presented. A numerical procedure for the solution of the governing differential equations is described, and models for chemical equilibrium and chemical kinetics calculations are presented. The chemical equilibrium model is used to characterize the hydrocarbon reactions. The chemical kinetics model is used to predict the concentrations of the oxides of nitrogen. The combustor consists of a cylindrical duct of varying cross sections with concentric streams of gaseous fuel and air entering the duct at one end. Four sample cases with specified inlet and boundary conditions are considered, and the results are discussed

  5. Prediction of the anti-inflammatory mechanisms of curcumin by module-based protein interaction network analysis.

    PubMed

    Gan, Yanxiong; Zheng, Shichao; Baak, Jan P A; Zhao, Silei; Zheng, Yongfeng; Luo, Nini; Liao, Wan; Fu, Chaomei

    2015-11-01

    Curcumin, the medically active component from Curcuma longa (Turmeric), is widely used to treat inflammatory diseases. Protein interaction network (PIN) analysis was used to predict its mechanisms of molecular action. Targets of curcumin were obtained based on ChEMBL and STITCH databases. Protein-protein interactions (PPIs) were extracted from the String database. The PIN of curcumin was constructed by Cytoscape and the function modules identified by gene ontology (GO) enrichment analysis based on molecular complex detection (MCODE). A PIN of curcumin with 482 nodes and 1688 interactions was constructed, which has scale-free, small world and modular properties. Based on analysis of these function modules, the mechanism of curcumin is proposed. Two modules were found to be intimately associated with inflammation. With function modules analysis, the anti-inflammatory effects of curcumin were related to SMAD, ERG and mediation by the TLR family. TLR9 may be a potential target of curcumin to treat inflammation. PMID:26713275

  6. Prediction of the anti-inflammatory mechanisms of curcumin by module-based protein interaction network analysis

    PubMed Central

    Gan, Yanxiong; Zheng, Shichao; Baak, Jan P.A.; Zhao, Silei; Zheng, Yongfeng; Luo, Nini; Liao, Wan; Fu, Chaomei

    2015-01-01

    Curcumin, the medically active component from Curcuma longa (Turmeric), is widely used to treat inflammatory diseases. Protein interaction network (PIN) analysis was used to predict its mechanisms of molecular action. Targets of curcumin were obtained based on ChEMBL and STITCH databases. Protein–protein interactions (PPIs) were extracted from the String database. The PIN of curcumin was constructed by Cytoscape and the function modules identified by gene ontology (GO) enrichment analysis based on molecular complex detection (MCODE). A PIN of curcumin with 482 nodes and 1688 interactions was constructed, which has scale-free, small world and modular properties. Based on analysis of these function modules, the mechanism of curcumin is proposed. Two modules were found to be intimately associated with inflammation. With function modules analysis, the anti-inflammatory effects of curcumin were related to SMAD, ERG and mediation by the TLR family. TLR9 may be a potential target of curcumin to treat inflammation. PMID:26713275

  7. Incorporation of gantry angle correction for 3D dose prediction in intensity-modulated radiation therapy

    PubMed Central

    Sumida, Iori; Yamaguchi, Hajime; Kizaki, Hisao; Aboshi, Keiko; Tsujii, Mari; Yamada, Yuji; Yagi, Masashi; Ogawa, Kazuhiko

    2015-01-01

    Pretreatment dose verification with beam-by-beam analysis for intensity-modulated radiation therapy (IMRT) is commonly performed with a gantry angle of 0° using a 2D diode detector array. Any changes in multileaf collimator (MLC) position between the actual treatment gantry angle and 0° may result in deviations from the planned dose. We evaluated the effects of MLC positioning errors between the actual treatment gantry angles and nominal gantry angles. A gantry angle correction (GAC) factor was generated by performing a non-gap test at various gantry angles using an electronic portal imaging device (EPID). To convert pixel intensity to dose at the MLC abutment positions, a non-gap test was performed using an EPID and a film at 0° gantry angle. We then assessed the correlations between pixel intensities and doses. Beam-by-beam analyses for 15 prostate IMRT cases as patient-specific quality assurance were performed with a 2D diode detector array at 0° gantry angle to determine the relative dose error for each beam. The resulting relative dose error with or without GAC was added back to the original dose grid for each beam. We compared the predicted dose distributions with or without GAC for film measurements to validate GAC effects. A gamma pass rate with a tolerance of 2%/2 mm was used to evaluate these dose distributions. The gamma pass rate with GAC was higher than that without GAC (P = 0.01). The predicted dose distribution improved with GAC, although the dosimetric effect to a patient was minimal. PMID:25742866

  8. In vitro blood-brain barrier permeability predictions for GABAA receptor modulating piperine analogs.

    PubMed

    Eigenmann, Daniela Elisabeth; Dürig, Carmen; Jähne, Evelyn Andrea; Smieško, Martin; Culot, Maxime; Gosselet, Fabien; Cecchelli, Romeo; Helms, Hans Christian Cederberg; Brodin, Birger; Wimmer, Laurin; Mihovilovic, Marko D; Hamburger, Matthias; Oufir, Mouhssin

    2016-06-01

    The alkaloid piperine from black pepper (Piper nigrum L.) and several synthetic piperine analogs were recently identified as positive allosteric modulators of γ-aminobutyric acid type A (GABAA) receptors. In order to reach their target sites of action, these compounds need to enter the brain by crossing the blood-brain barrier (BBB). We here evaluated piperine and five selected analogs (SCT-66, SCT-64, SCT-29, LAU397, and LAU399) regarding their BBB permeability. Data were obtained in three in vitro BBB models, namely a recently established human model with immortalized hBMEC cells, a human brain-like endothelial cells (BLEC) model, and a primary animal (bovine endothelial/rat astrocytes co-culture) model. For each compound, quantitative UHPLC-MS/MS methods in the range of 5.00-500ng/mL in the corresponding matrix were developed, and permeability coefficients in the three BBB models were determined. In vitro predictions from the two human BBB models were in good agreement, while permeability data from the animal model differed to some extent, possibly due to protein binding of the screened compounds. In all three BBB models, piperine and SCT-64 displayed the highest BBB permeation potential. This was corroborated by data from in silico prediction. For the other piperine analogs (SCT-66, SCT-29, LAU397, and LAU399), BBB permeability was low to moderate in the two human BBB models, and moderate to high in the animal BBB model. Efflux ratios (ER) calculated from bidirectional permeability experiments indicated that the compounds were likely not substrates of active efflux transporters. PMID:27018328

  9. Testing and Analysis for Lifetime Prediction of Crystalline Silicon PV Modules Undergoing Degradation by System Voltage Stress: Preprint

    SciTech Connect

    Hacke, P.; Smith, R.; Terwiliger, K.; Glick, S.; Jordan, D.; Johnston, S.; Kempe, M.; Kurtz, S.

    2012-07-01

    Acceleration factors are calculated for crystalline silicon PV modules under system voltage stress by comparing the module power during degradation outdoors to that in accelerated testing at three temperatures and 85% relative humidity. A lognormal analysis is applied to the accelerated lifetime test data considering failure at 80% of the initial module power. Activation energy of 0.73 eV for the rate of failure is determined, and the probability of module failure at an arbitrary temperature is predicted. To obtain statistical data for multiple modules over the course of degradation in-situ of the test chamber, dark I-V measurements are obtained and transformed using superposition, which is found well suited for rapid and quantitative evaluation of potential-induced degradation. It is determined that shunt resistance measurements alone do not represent the extent of power degradation. This is explained with a two-diode model analysis that shows an increasing second diode recombination current and ideality factor as the degradation in module power progresses. Failure modes of the modules stressed outdoors are examined and compared to those stressed in accelerated tests.

  10. Emotion regulation modulates anticipatory brain activity that predicts emotional memory encoding in women.

    PubMed

    Galli, Giulia; Griffiths, Victoria A; Otten, Leun J

    2014-03-01

    It has been shown that the effectiveness with which unpleasant events are encoded into memory is related to brain activity set in train before the events. Here, we assessed whether encoding-related activity before an aversive event can be modulated by emotion regulation. Electrical brain activity was recorded from the scalps of healthy women while they performed an incidental encoding task on randomly intermixed unpleasant and neutral visual scenes. A cue presented 1.5 s before each picture indicated the upcoming valence. In half of the blocks of trials, the instructions emphasized to let emotions arise in a natural way. In the other half, participants were asked to decrease their emotional response by adopting the perspective of a detached observer. Memory for the scenes was probed 1 day later with a recognition memory test. Brain activity before unpleasant scenes predicted later memory of the scenes, but only when participants felt their emotions and did not detach from them. The findings indicate that emotion regulation can eliminate the influence of anticipatory brain activity on memory encoding. This may be relevant for the understanding and treatment of psychiatric diseases with a memory component.

  11. Adaptive neuro-fuzzy prediction of modulation transfer function of optical lens system

    NASA Astrophysics Data System (ADS)

    Petković, Dalibor; Shamshirband, Shahaboddin; Anuar, Nor Badrul; Md Nasir, Mohd Hairul Nizam; Pavlović, Nenad T.; Akib, Shatirah

    2014-07-01

    The quantitative assessment of image quality is an important consideration in any type of imaging system. The modulation transfer function (MTF) is a graphical description of the sharpness and contrast of an imaging system or of its individual components. The MTF is also known and spatial frequency response. The MTF curve has different meanings according to the corresponding frequency. The MTF of an optical system specifies the contrast transmitted by the system as a function of image size, and is determined by the inherent optical properties of the system. In this study, the adaptive neuro-fuzzy (ANFIS) estimator is designed and adapted to predict MTF value of the actual optical system. Neural network in ANFIS adjusts parameters of membership function in the fuzzy logic of the fuzzy inference system. The back propagation learning algorithm is used for training this network. This intelligent estimator is implemented using MATLAB/Simulink and the performances are investigated. The simulation results presented in this paper show the effectiveness of the developed method.

  12. Suitability of frequency modulated thermal wave imaging for skin cancer detection-A theoretical prediction.

    PubMed

    Bhowmik, Arka; Repaka, Ramjee; Mulaveesala, Ravibabu; Mishra, Subhash C

    2015-07-01

    A theoretical study on the quantification of surface thermal response of cancerous human skin using the frequency modulated thermal wave imaging (FMTWI) technique has been presented in this article. For the first time, the use of the FMTWI technique for the detection and the differentiation of skin cancer has been demonstrated in this article. A three dimensional multilayered skin has been considered with the counter-current blood vessels in individual skin layers along with different stages of cancerous lesions based on geometrical, thermal and physical parameters available in the literature. Transient surface thermal responses of melanoma during FMTWI of skin cancer have been obtained by integrating the heat transfer model for biological tissue along with the flow model for blood vessels. It has been observed from the numerical results that, flow of blood in the subsurface region leads to a substantial alteration on the surface thermal response of the human skin. The alteration due to blood flow further causes a reduction in the performance of the thermal imaging technique during the thermal evaluation of earliest melanoma stages (small volume) compared to relatively large volume. Based on theoretical study, it has been predicted that the method is suitable for detection and differentiation of melanoma with comparatively large volume than the earliest development stages (small volume). The study has also performed phase based image analysis of the raw thermograms to resolve the different stages of melanoma volume. The phase images have been found to be clearly individuate the different development stages of melanoma compared to raw thermograms.

  13. Small Engine Technology (SET) - Task 13 ANOPP Noise Prediction for Small Engines: Jet Noise Prediction Module, Wing Shielding Module, and System Studies Results

    NASA Technical Reports Server (NTRS)

    Lieber, Lysbeth; Golub, Robert (Technical Monitor)

    2000-01-01

    This Final Report has been prepared by AlliedSignal Engines and Systems, Phoenix, Arizona, documenting work performed during the period May 1997 through June 1999, under the Small Engines Technology Program, Contract No. NAS3-27483, Task Order 13, ANOPP Noise Prediction for Small Engines. The report specifically covers the work performed under Subtasks 4, 5 and 6. Subtask 4 describes the application of a semi-empirical procedure for jet noise prediction, subtask 5 describes the development of a procedure to predict the effects of wing shielding, and subtask 6 describes the results of system studies of the benefits of the new noise technology on business and regional aircraft.

  14. State dependent model predictive control for orbital rendezvous using pulse-width pulse-frequency modulated thrusters

    NASA Astrophysics Data System (ADS)

    Li, Peng; Zhu, Zheng H.; Meguid, S. A.

    2016-07-01

    This paper studies the pulse-width pulse-frequency modulation based trajectory planning for orbital rendezvous and proximity maneuvering near a non-cooperative spacecraft in an elliptical orbit. The problem is formulated by converting the continuous control input, output from the state dependent model predictive control, into a sequence of pulses of constant magnitude by controlling firing frequency and duration of constant-magnitude thrusters. The state dependent model predictive control is derived by minimizing the control error of states and control roughness of control input for a safe, smooth and fuel efficient approaching trajectory. The resulting nonlinear programming problem is converted into a series of quadratic programming problem and solved by numerical iteration using the receding horizon strategy. The numerical results show that the proposed state dependent model predictive control with the pulse-width pulse-frequency modulation is able to effectively generate optimized trajectories using equivalent control pulses for the proximity maneuvering with less energy consumption.

  15. Attentional orienting to own and others' hands.

    PubMed

    Sanabria, Daniel; Madrid, Eduardo; Aranda, Clara; Ruz, María

    2015-08-01

    High-density electroencephalographic recordings were used to investigate the level of analysis at which attentional expectations modulate the processing of specific stimuli from the same perceptual category but differentiated in terms of a particular non-perceptual feature: body ownership. We used a task in which colour cues predicted whether a picture of a hand stimulus belonged to the participant or to somebody else. Participants were instructed to respond whether the target was a left or a right hand. Results revealed that the ERP pattern depended on stimulus ownership and attention orienting, which influenced the visual processing of own and someone else's hands differentially. Larger amplitude for others' than for own hands was shown at the N1 deflection (at the right hemisphere). Attentional effects were found at the P2 and P3 potentials. The P2 reflected an interaction between stimulus ownership and attentional orienting, due to a larger validity effect for others' hands. At the P3 level, the data showed a significant validity effect only for self-hand stimuli. In sum, our results suggest that (1) differences as a function of stimulus ownership can be detected at early levels of stimulus processing; (2) endogenous attention can be directed to exemplars within the same category, hand stimuli in this case; (3) the effects of attention are modulated by ownership. PMID:25953649

  16. Attention-dependent reductions in burstiness and action potential height in macaque area V4

    PubMed Central

    Anderson, Emily B.; Mitchell, Jude F.; Reynolds, John H.

    2013-01-01

    Attention improves the encoding of visual stimuli. One mechanism that is implicated in facilitating sensory encoding is the firing of action potentials in bursts. We tested the hypothesis that when spatial attention is directed to a stimulus, this causes an increase in burst firing to the attended stimulus. To the contrary, we found an attention-dependent reduction in burstiness among putative pyramidal neurons in macaque area V4. We accounted for this using a conductance-based Hodgkin-Huxley style model in which attentional modulation stems from scaling excitation and inhibition. The model exhibited attention-dependent increases in firing rate and made the surprising and correct prediction that when attention is directed into a neuron’s receptive field, this reduces action potential height. The model thus provided a unified explanation for three distinct forms of attentional modulation, two of them novel, and implicates scaling of the responses of excitatory and inhibitory input populations in mediating attention. PMID:23852114

  17. An Integrated Theory of Prospective Time Interval Estimation: The Role of Cognition, Attention, and Learning

    ERIC Educational Resources Information Center

    Taatgen, Niels A.; van Rijn, Hedderik; Anderson, John

    2007-01-01

    A theory of prospective time perception is introduced and incorporated as a module in an integrated theory of cognition, thereby extending existing theories and allowing predictions about attention and learning. First, a time perception module is established by fitting existing datasets (interval estimation and bisection and impact of secondary…

  18. A Western diet ecological module identified from the 'humanized' mouse microbiota predicts diet in adults and formula feeding in children.

    PubMed

    Siddharth, Jay; Holway, Nicholas; Parkinson, Scott J

    2013-01-01

    The interplay between diet and the microbiota has been implicated in the growing frequency of chronic diseases associated with the Western lifestyle. However, the complexity and variability of microbial ecology in humans and preclinical models has hampered identification of the molecular mechanisms underlying the association of the microbiota in this context. We sought to address two key questions. Can the microbial ecology of preclinical models predict human populations? And can we identify underlying principles that surpass the plasticity of microbial ecology in humans? To do this, we focused our study on diet; perhaps the most influential factor determining the composition of the gut microbiota. Beginning with a study in 'humanized' mice we identified an interactive module of 9 genera allied with Western diet intake. This module was applied to a controlled dietary study in humans. The abundance of the Western ecological module correctly predicted the dietary intake of 19/21 top and 21/21 of the bottom quartile samples inclusive of all 5 Western and 'low-fat' diet subjects, respectively. In 98 volunteers the abundance of the Western module correlated appropriately with dietary intake of saturated fatty acids, fat-soluble vitamins and fiber. Furthermore, it correlated with the geographical location and dietary habits of healthy adults from the Western, developing and third world. The module was also coupled to dietary intake in children (and piglets) correlating with formula (vs breast) feeding and associated with a precipitous development of the ecological module in young children. Our study provides a conceptual platform to translate microbial ecology from preclinical models to humans and identifies an ecological network module underlying the association of the gut microbiota with Western dietary habits.

  19. General inattentiveness is a long-term reliable trait independently predictive of psychological health: Danish validation studies of the Mindful Attention Awareness Scale.

    PubMed

    Jensen, Christian Gaden; Niclasen, Janni; Vangkilde, Signe Allerup; Petersen, Anders; Hasselbalch, Steen Gregers

    2016-05-01

    The Mindful Attention Awareness Scale (MAAS) measures perceived degree of inattentiveness in different contexts and is often used as a reversed indicator of mindfulness. MAAS is hypothesized to reflect a psychological trait or disposition when used outside attentional training contexts, but the long-term test-retest reliability of MAAS scores is virtually untested. It is unknown whether MAAS predicts psychological health after controlling for standardized socioeconomic status classifications. First, MAAS translated to Danish was validated psychometrically within a randomly invited healthy adult community sample (N = 490). Factor analysis confirmed that MAAS scores quantified a unifactorial construct of excellent composite reliability and consistent convergent validity. Structural equation modeling revealed that MAAS scores contributed independently to predicting psychological distress and mental health, after controlling for age, gender, income, socioeconomic occupational class, stressful life events, and social desirability (β = 0.32-.42, ps < .001). Second, MAAS scores showed satisfactory short-term test-retest reliability in 100 retested healthy university students. Finally, MAAS sample mean scores as well as individuals' scores demonstrated satisfactory test-retest reliability across a 6 months interval in the adult community (retested N = 407), intraclass correlations ≥ .74. MAAS scores displayed significantly stronger long-term test-retest reliability than scores measuring psychological distress (z = 2.78, p = .005). Test-retest reliability estimates did not differ within demographic and socioeconomic strata. Scores on the Danish MAAS were psychometrically validated in healthy adults. MAAS's inattentiveness scores reflected a unidimensional construct, long-term reliable disposition, and a factor of independent significance for predicting psychological health. (PsycINFO Database Record

  20. Interactions of attention, emotion and motivation.

    PubMed

    Raymond, Jane

    2009-01-01

    Although successful visually guided action begins with sensory processes and ends with motor control, the intervening processes related to the appropriate selection of information for processing are especially critical because of the brain's limited capacity to handle information. Three important mechanisms--attention, emotion and motivation--contribute to the prioritization and selection of information. In this chapter, the interplay between these systems is discussed with emphasis placed on interactions between attention (or immediate task relevance of stimuli) and emotion (or affective evaluation of stimuli), and between attention and motivation (or the predicted value of stimuli). Although numerous studies have shown that emotional stimuli modulate mechanisms of selective attention in humans, little work has been directed at exploring whether such interactions can be reciprocal, that is, whether attention can influence emotional response. Recent work on this question (showing that distracting information is typically devalued upon later encounters) is reviewed in the first half of the chapter. In the second half, some recent experiments exploring how prior value-prediction learning (i.e., learning to associate potential outcomes, good or bad, with specific stimuli) plays a role in visual selection and conscious perception. The results indicate that some aspects of motivation act on selection independently of traditionally defined attention and other aspects interact with it.

  1. Deconstructing Interocular Suppression: Attention and Divisive Normalization.

    PubMed

    Li, Hsin-Hung; Carrasco, Marisa; Heeger, David J

    2015-10-01

    In interocular suppression, a suprathreshold monocular target can be rendered invisible by a salient competitor stimulus presented in the other eye. Despite decades of research on interocular suppression and related phenomena (e.g., binocular rivalry, flash suppression, continuous flash suppression), the neural processing underlying interocular suppression is still unknown. We developed and tested a computational model of interocular suppression. The model included two processes that contributed to the strength of interocular suppression: divisive normalization and attentional modulation. According to the model, the salient competitor induced a stimulus-driven attentional modulation selective for the location and orientation of the competitor, thereby increasing the gain of neural responses to the competitor and reducing the gain of neural responses to the target. Additional suppression was induced by divisive normalization in the model, similar to other forms of visual masking. To test the model, we conducted psychophysics experiments in which both the size and the eye-of-origin of the competitor were manipulated. For small and medium competitors, behavioral performance was consonant with a change in the response gain of neurons that responded to the target. But large competitors induced a contrast-gain change, even when the competitor was split between the two eyes. The model correctly predicted these results and outperformed an alternative model in which the attentional modulation was eye specific. We conclude that both stimulus-driven attention (selective for location and feature) and divisive normalization contribute to interocular suppression.

  2. Right hemisphere dominance directly predicts both baseline V1 cortical excitability and the degree of top-down modulation exerted over low-level brain structures.

    PubMed

    Arshad, Q; Siddiqui, S; Ramachandran, S; Goga, U; Bonsu, A; Patel, M; Roberts, R E; Nigmatullina, Y; Malhotra, P; Bronstein, A M

    2015-12-17

    Right hemisphere dominance for visuo-spatial attention is characteristically observed in most right-handed individuals. This dominance has been attributed to both an anatomically larger right fronto-parietal network and the existence of asymmetric parietal interhemispheric connections. Previously it has been demonstrated that interhemispheric conflict, which induces left hemisphere inhibition, results in the modulation of both (i) the excitability of the early visual cortex (V1) and (ii) the brainstem-mediated vestibular-ocular reflex (VOR) via top-down control mechanisms. However to date, it remains unknown whether the degree of an individual's right hemisphere dominance for visuospatial function can influence, (i) the baseline excitability of the visual cortex and (ii) the extent to which the right hemisphere can exert top-down modulation. We directly tested this by correlating line bisection error (or pseudoneglect), taken as a measure of right hemisphere dominance, with both (i) visual cortical excitability measured using phosphene perception elicited via single-pulse occipital trans-cranial magnetic stimulation (TMS) and (ii) the degree of trans-cranial direct current stimulation (tDCS)-mediated VOR suppression, following left hemisphere inhibition. We found that those individuals with greater right hemisphere dominance had a less excitable early visual cortex at baseline and demonstrated a greater degree of vestibular nystagmus suppression following left hemisphere cathodal tDCS. To conclude, our results provide the first demonstration that individual differences in right hemisphere dominance can directly predict both the baseline excitability of low-level brain structures and the degree of top-down modulation exerted over them. PMID:26518461

  3. Right hemisphere dominance directly predicts both baseline V1 cortical excitability and the degree of top-down modulation exerted over low-level brain structures.

    PubMed

    Arshad, Q; Siddiqui, S; Ramachandran, S; Goga, U; Bonsu, A; Patel, M; Roberts, R E; Nigmatullina, Y; Malhotra, P; Bronstein, A M

    2015-12-17

    Right hemisphere dominance for visuo-spatial attention is characteristically observed in most right-handed individuals. This dominance has been attributed to both an anatomically larger right fronto-parietal network and the existence of asymmetric parietal interhemispheric connections. Previously it has been demonstrated that interhemispheric conflict, which induces left hemisphere inhibition, results in the modulation of both (i) the excitability of the early visual cortex (V1) and (ii) the brainstem-mediated vestibular-ocular reflex (VOR) via top-down control mechanisms. However to date, it remains unknown whether the degree of an individual's right hemisphere dominance for visuospatial function can influence, (i) the baseline excitability of the visual cortex and (ii) the extent to which the right hemisphere can exert top-down modulation. We directly tested this by correlating line bisection error (or pseudoneglect), taken as a measure of right hemisphere dominance, with both (i) visual cortical excitability measured using phosphene perception elicited via single-pulse occipital trans-cranial magnetic stimulation (TMS) and (ii) the degree of trans-cranial direct current stimulation (tDCS)-mediated VOR suppression, following left hemisphere inhibition. We found that those individuals with greater right hemisphere dominance had a less excitable early visual cortex at baseline and demonstrated a greater degree of vestibular nystagmus suppression following left hemisphere cathodal tDCS. To conclude, our results provide the first demonstration that individual differences in right hemisphere dominance can directly predict both the baseline excitability of low-level brain structures and the degree of top-down modulation exerted over them.

  4. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure.

    PubMed

    Miconi, Thomas; VanRullen, Rufin

    2016-02-01

    Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space. Several existing models of attention suggest that these effects arise from selective modulation of neural inputs. However, anatomical and physiological observations suggest that attentional modulation targets higher levels of the visual system (such as V4 or MT) rather than input areas (such as V1). Here we propose a simple mechanism that explains how a top-down attentional modulation, falling on higher visual areas, can produce the observed effects of attention on neural responses. Our model requires only the existence of modulatory feedback connections between areas, and short-range lateral inhibition within each area. Feedback connections redistribute the top-down modulation to lower areas, which in turn alters the inputs of other higher-area cells, including those that did not receive the initial modulation. This produces firing rate modulations and receptive field shifts. Simultaneously, short-range lateral inhibition between neighboring cells produce competitive effects that are automatically scaled to receptive field size in any given area. Our model reproduces the observed attentional effects on response rates (response gain, input gain, biased competition automatically scaled to receptive field size) and receptive field structure (shifts and resizing of receptive fields both spatially and in complex feature space), without modifying model parameters. Our model also makes the novel prediction that attentional effects on response curves should shift from response gain to contrast gain as the spatial focus of attention drifts away from the studied cell. PMID:26890584

  5. Baseline-dependent modulating effects of nicotine on voluntary and involuntary attention measured with brain event-related P3 potentials.

    PubMed

    Knott, Verner; Choueiry, Joelle; Dort, Heather; Smith, Dylan; Impey, Danielle; de la Salle, Sara; Philippe, Tristan

    2014-07-01

    Cholinergic stimulation produces cognitive effects that vary across individuals, and stimulus/task conditions. As of yet, the role of individual differences in moderating the effects of the nicotinic acetylcholine receptor agonist nicotine on specific attentional functions and their neural and behavioral correlates is not fully understood. In this randomized, double-blind, placebo-controlled study of 64 healthy non-smokers, we address the contribution of baseline-dependence to inter-individual variability in response to nicotine gum (6 mg) assessed with event-related brain potential (ERP) indices of involuntary (the anteriorly distributed P3a) and voluntary (the posteriorly distributed P3b) attention derived from an active 3-stimulus auditory oddball paradigm involving listening to standard and novel stimuli and detection and response to target stimuli. Nicotine enhanced the amplitude of P3a elicited during the processing of novel stimuli but only in individuals with relatively low baseline P3a amplitudes. Exhibiting an inverted-U nicotine response profile, target P3b and standard N1 amplitudes were increased and decreased in participants with low and high baseline amplitudes, respectively. In all, the findings corroborate the involvement of nicotinic mechanisms in attention, generally acting to increase attentional capacity in relatively low attentional functioning (reduced baseline ERPs) individuals, while having negative or detrimental effects in those with medium/high attentional levels (increased baseline ERPs), and in a manner that is differentially expressed during bottom-up (involuntary) attentional capture and top-down (voluntary) attentional allocation.

  6. Shifting Attention

    ERIC Educational Resources Information Center

    Ingram, Jenni

    2014-01-01

    This article examines the shifts in attention and focus as one teacher introduces and explains an image that represents the processes involved in a numeric problem that his students have been working on. This paper takes a micro-analytic approach to examine how the focus of attention shifts through what the teacher and students do and say in the…

  7. Capturing Attention When Attention "Blinks"

    ERIC Educational Resources Information Center

    Wee, Serena; Chua, Fook K.

    2004-01-01

    Four experiments addressed the question of whether attention may be captured when the visual system is in the midst of an attentional blink (AB). Participants identified 2 target letters embedded among distractor letters in a rapid serial visual presentation sequence. In some trials, a square frame was inserted between the targets; as the only…

  8. Nicotinic receptors and attention.

    PubMed

    Hahn, Britta

    2015-01-01

    Facilitation of different attentional functions by nicotinic acetylcholine receptor (nAChR) agonists may be of therapeutic potential in disease conditions such as Alzheimer's disease or schizophrenia. For this reason, the neuronal mechanisms underlying these effects have been the focus of research in humans and in preclinical models. Attention-enhancing effects of the nonselective nAChR agonist nicotine can be observed in human nonsmokers and in laboratory animals, suggesting that benefits go beyond a reversal of withdrawal deficits in smokers. The ultimate aim is to develop compounds acting with greater selectivity than nicotine at a subset of nAChRs, with an effects profile narrowly matching the targeted cognitive deficits and minimizing unwanted effects. To date, compounds tested clinically target the nAChR subtypes most abundant in the brain. To help pinpoint more selectively expressed subtypes critical for attention, studies have aimed at identifying the secondary neurotransmitter systems whose stimulation mediates the attention-enhancing properties of nicotine. Evidence indicates that noradrenaline and glutamate, but not dopamine release, are critical mediators. Thus, attention-enhancing nAChR agents could spare the system central to nicotine dependence. Neuroimaging studies suggest that nAChR agonists act on a variety of brain systems by enhancing activation, reducing activation, and enhancing deactivation by attention tasks. This supports the notion that effects on different attentional functions may be mediated by distinct central mechanisms, consistent with the fact that nAChRs interact with a multitude of brain sites and neurotransmitter systems. The challenge will be to achieve the optimal tone at the right subset of nAChR subtypes to modulate specific attentional functions, employing not just direct agonist properties, but also positive allosteric modulation and low-dose antagonism.

  9. Controllability modulates the neural response to predictable but not unpredictable threat in humans.

    PubMed

    Wood, Kimberly H; Wheelock, Muriah D; Shumen, Joshua R; Bowen, Kenton H; Ver Hoef, Lawrence W; Knight, David C

    2015-10-01

    Stress resilience is mediated, in part, by our ability to predict and control threats within our environment. Therefore, determining the neural mechanisms that regulate the emotional response to predictable and controllable threats may provide important new insight into the processes that mediate resilience to emotional dysfunction and guide the future development of interventions for anxiety disorders. To better understand the effect of predictability and controllability on threat-related brain activity in humans, two groups of healthy volunteers participated in a yoked Pavlovian fear conditioning study during functional magnetic resonance imaging (fMRI). Threat predictability was manipulated by presenting an aversive unconditioned stimulus (UCS) that was either preceded by a conditioned stimulus (i.e., predictable) or by presenting the UCS alone (i.e., unpredictable). Similar to animal model research that has employed yoked fear conditioning procedures, one group (controllable condition; CC), but not the other group (uncontrollable condition; UC) was able to terminate the UCS. The fMRI signal response within the dorsolateral prefrontal cortex (PFC), dorsomedial PFC, ventromedial PFC, and posterior cingulate was diminished during predictable compared to unpredictable threat (i.e., UCS). In addition, threat-related activity within the ventromedial PFC and bilateral hippocampus was diminished only to threats that were both predictable and controllable. These findings provide insight into how threat predictability and controllability affects the activity of brain regions (i.e., ventromedial PFC and hippocampus) involved in emotion regulation, and may have important implications for better understanding neural processes that mediate emotional resilience to stress.

  10. Predictions of Visual Content across Eye Movements and Their Modulation by Inferred Information.

    PubMed

    Ehinger, Benedikt V; König, Peter; Ossandón, José P

    2015-05-13

    The brain is proposed to operate through probabilistic inference, testing and refining predictions about the world. Here, we search for neural activity compatible with the violation of active predictions, learned from the contingencies between actions and the consequent changes in sensory input. We focused on vision, where eye movements produce stimuli shifts that could, in principle, be predicted. We compared, in humans, error signals to saccade-contingent changes of veridical and inferred inputs by contrasting the electroencephalographic activity after saccades to a stimulus presented inside or outside the blind spot. We observed early (<250 ms) and late (>250 ms) error signals after stimulus change, indicating the violation of sensory and associative predictions, respectively. Remarkably, the late response was diminished for blind-spot trials. These results indicate that predictive signals occur across multiple levels of the visual hierarchy, based on generative models that differentiate between signals that originate from the outside world and those that are inferred. PMID:25972169

  11. Poverty, household chaos, and interparental aggression predict children's ability to recognize and modulate negative emotions.

    PubMed

    Raver, C Cybele; Blair, Clancy; Garrett-Peters, Patricia

    2015-08-01

    The following prospective longitudinal study considers the ways that protracted exposure to verbal and physical aggression between parents may take a substantial toll on emotional adjustment for 1,025 children followed from 6 to 58 months of age. Exposure to chronic poverty from infancy to early childhood as well as multiple measures of household chaos were also included as predictors of children's ability to recognize and modulate negative emotions in order to disentangle the role of interparental conflict from the socioeconomic forces that sometimes accompany it. Analyses revealed that exposure to greater levels of interparental conflict, more chaos in the household, and a higher number of years in poverty can be empirically distinguished as key contributors to 58-month-olds' ability to recognize and modulate negative emotion. Implications for models of experiential canalization of emotional processes within the context of adversity are discussed.

  12. Feature processing and attention in the human visual system: an overview.

    PubMed

    Heslenfeld, D J; Kenemans, J L; Kok, A; Molenaar, P C

    1997-03-21

    A recent development in the cognitive modelling of visual selective attention is the incorporation of design principles derived from the neuroanatomy and neurophysiology of the primate visual system. In this paper, we describe these recent 'neurocognitive' models in more detail, point out the underlying neurobiological principles, and show that in all cases attention is implemented as an energetical resource which can be directed to representations and pathways in the system. In the second part of the paper, we specify the predictions derived from this 'energy hypothesis', and evaluate available data pertaining to this issue. We present new analyses of electrophysiological data in order to directly test the hypothesis that attention modulates feature-specific representations. It will be shown that in the case of sustained spatial attention, the data are in agreement with this hypothesis, whereas in the case of nonspatial attention, there is no evidence of a modulation of feature-specific pathways by attention. PMID:9083650

  13. Controllability modulates the neural response to predictable but not unpredictable threat in humans.

    PubMed

    Wood, Kimberly H; Wheelock, Muriah D; Shumen, Joshua R; Bowen, Kenton H; Ver Hoef, Lawrence W; Knight, David C

    2015-10-01

    Stress resilience is mediated, in part, by our ability to predict and control threats within our environment. Therefore, determining the neural mechanisms that regulate the emotional response to predictable and controllable threats may provide important new insight into the processes that mediate resilience to emotional dysfunction and guide the future development of interventions for anxiety disorders. To better understand the effect of predictability and controllability on threat-related brain activity in humans, two groups of healthy volunteers participated in a yoked Pavlovian fear conditioning study during functional magnetic resonance imaging (fMRI). Threat predictability was manipulated by presenting an aversive unconditioned stimulus (UCS) that was either preceded by a conditioned stimulus (i.e., predictable) or by presenting the UCS alone (i.e., unpredictable). Similar to animal model research that has employed yoked fear conditioning procedures, one group (controllable condition; CC), but not the other group (uncontrollable condition; UC) was able to terminate the UCS. The fMRI signal response within the dorsolateral prefrontal cortex (PFC), dorsomedial PFC, ventromedial PFC, and posterior cingulate was diminished during predictable compared to unpredictable threat (i.e., UCS). In addition, threat-related activity within the ventromedial PFC and bilateral hippocampus was diminished only to threats that were both predictable and controllable. These findings provide insight into how threat predictability and controllability affects the activity of brain regions (i.e., ventromedial PFC and hippocampus) involved in emotion regulation, and may have important implications for better understanding neural processes that mediate emotional resilience to stress. PMID:26149610

  14. Controllability Modulates the Neural Response to Predictable but not Unpredictable Threat in Humans

    PubMed Central

    Wood, Kimberly H.; Wheelock, Muriah D.; Shumen, Joshua R.; Bowen, Kenton H.; Ver Hoef, Lawrence W.; Knight, David C.

    2015-01-01

    Stress resilience is mediated, in part, by our ability to predict and control threats within our environment. Therefore, determining the neural mechanisms that regulate the emotional response to predictable and controllable threat may provide important new insight into the processes that mediate resilience to emotional dysfunction and guide the future development of interventions for anxiety disorders. To better understand the effect of predictability and controllability on threat-related brain activity in humans, two groups of healthy volunteers participated in a yoked Pavlovian fear conditioning study during functional magnetic resonance imaging (fMRI). Threat predictability was manipulated by presenting an aversive unconditioned stimulus (UCS) that was either preceded by a conditioned stimulus (i.e., predictable) or by presenting the UCS alone (i.e., unpredictable). Similar to animal model research that has employed yoked fear conditioning procedures, one group (Controllable Condition; CC), but not the other group (Uncontrollable Condition; UC) was able to terminate the UCS. The fMRI signal response within the dorsolateral prefrontal cortex (PFC), dorsomedial PFC, ventromedial PFC, and posterior cingulate was diminished during predictable compared to unpredictable threat (i.e., UCS). In addition, threat-related activity within the ventromedial PFC and bilateral hippocampus was diminished only to threats that were both predictable and controllable. These findings provide insight into how threat predictability and controllability affects the activity of brain regions (i.e., ventromedial PFC and hippocampus) involved in emotion regulation, and may have important implications for better understanding neural processes that mediate emotional resilience to stress. PMID:26149610

  15. Dopaminergic and Cholinergic Modulations of Visual-Spatial Attention and Working Memory: Insights from Molecular Genetic Research and Implications for Adult Cognitive Development

    ERIC Educational Resources Information Center

    Stormer, Viola S.; Passow, Susanne; Biesenack, Julia; Li, Shu-Chen

    2012-01-01

    Attention and working memory are fundamental for selecting and maintaining behaviorally relevant information. Not only do both processes closely intertwine at the cognitive level, but they implicate similar functional brain circuitries, namely the frontoparietal and the frontostriatal networks, which are innervated by cholinergic and dopaminergic…

  16. Cortical State and Attention

    PubMed Central

    Harris, Kenneth D.; Thiele, Alexander

    2012-01-01

    Preface The brain continuously adapts its processing machinery to behavioural demands. To achieve this it rapidly modulates the operating mode of cortical circuits, controlling the way information is transformed and routed. This article will focus on two experimental approaches by which the control of cortical information processing has been investigated: the study of state-dependent cortical processing in rodents, and attention in the primate visual system. Both processes involve a modulation of low-frequency activity fluctuations and spiking correlation, and are mediated by common receptor systems. We suggest that selective attention involves processes similar to state change, operating at a local columnar level to enhance the representation of otherwise nonsalient features while suppressing internally generated activity patterns. PMID:21829219

  17. Predicting Modulation in Corticomotor Excitability and in Transcallosal Inhibition in Response to Anodal Transcranial Direct Current Stimulation

    PubMed Central

    Davidson, Travis W.; Bolic, Miodrag; Tremblay, François

    2016-01-01

    Introduction: Responses to neuromodulatory protocols based either on transcranial direct current stimulation (tDCS) or transcranial magnetic stimulation (TMS) are known to be highly variable between individuals. In this study, we examined whether variability of responses to anodal tDCS (a-tDCS) could be predicted from individual differences in the ability to recruit early or late indirect waves (I-waves), as reflected in latency differences of motor evoked potentials (MEPs) evoked by TMS of different coil orientation. Methods: Participants (n = 20) first underwent TMS to measure latency of MEPs elicited at different coil orientations (i.e., PA, posterior-anterior; AP, anterior-posterior; LM, latero-medial). Then, participants underwent a-tDCS (20 min @ 2 mA) targeting the primary motor cortex of the contralateral preferred hand (right, n = 18). Individual responses to a-tDCS were determined by monitoring changes in MEP amplitude at rest and in the duration of the contralateral silent period (cSP) and ipsilateral silent period (iSP) during contraction; the latter providing an index of the latency and duration of transcallosal inhibition (LTI and DTI). Results: Consistent with previous reports, individual responses to a-tDCS were highly variable when expressed in terms of changes in MEP amplitude or in cSP duration with ~50% of the participants showing either little or no modulation. In contrast, individual variations in measures of transcallosal inhibition were less variable, allowing detection of significant after-effects. The reduced LTI and prolonged DTI observed post-tDCS were indicative of an enhanced excitability of the transcallosal pathway in the stimulated hemisphere. In terms of predictions, AP-LM latency differences proved to be good predictors of responses to a-tDCS when considering MEP modulation. Conclusion: The present results corroborate the predictive value of latency differences derived from TMS to determine who is likely to express

  18. Traveling-Wave Tube Amplifier Model to Predict High-Order Modulation Intersymbol Interference

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.; Andro, Monty; Williams, W. D. (Technical Monitor)

    2001-01-01

    Demands for increased data rates in satellite communications necessitate higher order modulation schemes, larger system bandwidth, and minimum distortion of the modulated signal as it is passed through the traveling wave tube amplifier (TWTA). One type of distortion that the TWTA contributes to is intersymbol interference (ISI), and this becomes particularly disruptive with wide-band, complex modulation schemes. It is suspected that in addition to the dispersion of the TWT, frequency dependent reflections due to mismatches within the TWT are a significant contributor to ISI. To experimentally investigate the effect of these mismatches within the physical TWT on ISI would be prohibitively expensive, as it would require manufacturing numerous amplifiers in addition to the acquisition of the required digital hardware. In an attempt to develop a more accurate model to correlate IS1 with the TWTA and the operational signal, a fully three-dimensional (3D), time-dependent, TWT interaction model has been developed using the electromagnetic particle-in-cell (PIC) code MAFIA (solution of Maxwell's equations by the Finite-Integration-Algorithm). The model includes a user defined slow-wave circuit with a spatially tapered region of loss to implement a sever, and spatially varied geometry (such as helical pitch) to implement a phase velocity taper. The model also includes user defined input/output coupling and an electron beam contained by solenoidal, electrostatic, or periodic permanent magnet (PPM) focusing allowing standard or novel TWTs to be investigated. This model comprehensively takes into account the effects of frequency dependent nonlinear distortions (MAM and AMPM); gain ripple due to frequency dependent reflections at the input/output coupling, severs, and mismatches from dynamic pitch variations; drive induced oscillations; harmonic generation; intermodulation products; and backward waves.

  19. Attention Genes

    ERIC Educational Resources Information Center

    Posner, Michael I.; Rothbart, Mary K.; Sheese, Brad E.

    2007-01-01

    A major problem for developmental science is understanding how the cognitive and emotional networks important in carrying out mental processes can be related to individual differences. The last five years have seen major advances in establishing links between alleles of specific genes and the neural networks underlying aspects of attention. These…

  20. ACTP: A webserver for predicting potential targets and relevant pathways of autophagy-modulating compounds

    PubMed Central

    Ouyang, Liang; Cai, Haoyang; Liu, Bo

    2016-01-01

    Autophagy (macroautophagy) is well known as an evolutionarily conserved lysosomal degradation process for long-lived proteins and damaged organelles. Recently, accumulating evidence has revealed a series of small-molecule compounds that may activate or inhibit autophagy for therapeutic potential on human diseases. However, targeting autophagy for drug discovery still remains in its infancy. In this study, we developed a webserver called Autophagic Compound-Target Prediction (ACTP) (http://actp.liu-lab.com/) that could predict autophagic targets and relevant pathways for a given compound. The flexible docking of submitted small-molecule compound (s) to potential autophagic targets could be performed by backend reverse docking. The webpage would return structure-based scores and relevant pathways for each predicted target. Thus, these results provide a basis for the rapid prediction of potential targets/pathways of possible autophagy-activating or autophagy-inhibiting compounds without labor-intensive experiments. Moreover, ACTP will be helpful to shed light on identifying more novel autophagy-activating or autophagy-inhibiting compounds for future therapeutic implications. PMID:26824420

  1. Dose to Larynx Predicts for Swallowing Complications After Intensity-Modulated Radiotherapy

    SciTech Connect

    Caglar, Hale B.; Tishler, Roy B.; Burke, Elaine; Li Yi; Goguen, Laura; Norris, Carl M.; Allen, Aaron M.

    2008-11-15

    Purpose: To evaluate early swallowing after intensity-modulated radiotherapy for head and neck squamous cell carcinoma and determine factors correlating with aspiration and/or stricture. Methods and Materials: Consecutive patients treated with intensity-modulated radiotherapy with or without chemotherapy between September 2004 and August 2006 at the Dana Farber Cancer Institute/Brigham and Women's Hospital were evaluated with institutional review board approval. Patients underwent swallowing evaluation after completion of therapy; including video swallow studies. The clinical- and treatment-related variables were examined for correlation with aspiration or strictures, as well as doses to the larynx, pharyngeal constrictor muscles, and cervical esophagus. The correlation was assessed with logistic regression analysis. Results: A total of 96 patients were evaluated. Their median age was 55 years, and 79 (82%) were men. The primary site of cancer was the oropharynx in 43, hypopharynx/larynx in 17, oral cavity in 13, nasopharynx in 11, maxillary sinus in 2, and unknown primary in 10. Of the 96 patients, 85% underwent definitive RT and 15% postoperative RT. Also, 28 patients underwent induction chemotherapy followed by concurrent chemotherapy, 59 received concurrent chemotherapy, and 9 patients underwent RT alone. The median follow-up was 10 months. Of the 96 patients, 31 (32%) had clinically significant aspiration and 36 (37%) developed a stricture. The radiation dose-volume metrics, including the volume of the larynx receiving {>=}50 Gy (p = 0.04 and p = 0.03, respectively) and volume of the inferior constrictor receiving {>=}50 Gy (p = 0.05 and p = 0.02, respectively) were significantly associated with both aspiration and stricture. The mean larynx dose correlated with aspiration (p = 0.003). Smoking history was the only clinical factor to correlate with stricture (p = 0.05) but not aspiration. Conclusion: Aspiration and stricture are common side effects after

  2. Neural variability in premotor cortex is modulated by trial history and predicts behavioral performance.

    PubMed

    Marcos, Encarni; Pani, Pierpaolo; Brunamonti, Emiliano; Deco, Gustavo; Ferraina, Stefano; Verschure, Paul

    2013-04-24

    In the study of decision making, emphasis is placed on different forms of perceptual integration, while the influence of other factors, such as memory, is ignored. In addition, it is believed that the information underlying decision making is carried in the rate of the neuronal response, while its variability is considered unspecific. Here we studied the influence of recent experience on motor decision making by analyzing the activity of neurons in the dorsal premotor area of two monkeys performing a countermanding arm task. We observe that the across-trial variability of the neural response strongly correlates with trial history-dependent changes in reaction time. Using a theoretical model of decision making, we show that a trial history-monitoring signal can explain the observed behavioral and neural modulation. Our study reveals that, in the neural processes that culminate in motor plan maturation, the evidence provided by perception and memory is reflected in mean rate and variance respectively. PMID:23622062

  3. Attention Reorients Periodically.

    PubMed

    Dugué, Laura; Roberts, Mariel; Carrasco, Marisa

    2016-06-20

    Reorienting of voluntary attention enables the processing of stimuli at previously unattended locations. Although studies have identified a ventral fronto-parietal network underlying attention [1, 2], little is known about whether and how early visual areas are involved in involuntary [3, 4] and even less in voluntary [5] reorienting, and their temporal dynamics are unknown. We used transcranial magnetic stimulation (TMS) over the occipital cortex to interfere with attentional reorienting and study its role and temporal dynamics in this process. Human observers performed an orientation discrimination task, with either valid or invalid attention cueing, across a range of stimulus contrasts. Valid cueing induced a behavioral response gain increase, higher asymptotic performance for attended than unattended locations. During subsequent TMS sessions, observers performed the same task, with high stimulus contrast. Based on phosphene mapping, TMS double pulses were applied at one of various delays to a consistent brain location in retinotopic areas (V1/V2), corresponding to the evoked signal of the target or distractor, in a valid or invalid trial. Thus, the stimulation was identical for the four experimental conditions (valid/invalid cue condition × target/distractor-stimulated). TMS modulation of the target and distractor were both periodic (5 Hz, theta) and out of phase with respect to each other in invalid trials only, when attention had to be disengaged from the distractor and reoriented to the target location. Reorientation of voluntary attention periodically involves V1/V2 at the theta frequency. These results suggest that TMS probes theta phase-reset by attentional reorienting and help link periodic sampling in time and attention reorienting in space.

  4. CisMiner: Genome-Wide In-Silico Cis-Regulatory Module Prediction by Fuzzy Itemset Mining

    PubMed Central

    Navarro, Carmen; Lopez, Francisco J.; Cano, Carlos; Garcia-Alcalde, Fernando; Blanco, Armando

    2014-01-01

    Eukaryotic gene control regions are known to be spread throughout non-coding DNA sequences which may appear distant from the gene promoter. Transcription factors are proteins that coordinately bind to these regions at transcription factor binding sites to regulate gene expression. Several tools allow to detect significant co-occurrences of closely located binding sites (cis-regulatory modules, CRMs). However, these tools present at least one of the following limitations: 1) scope limited to promoter or conserved regions of the genome; 2) do not allow to identify combinations involving more than two motifs; 3) require prior information about target motifs. In this work we present CisMiner, a novel methodology to detect putative CRMs by means of a fuzzy itemset mining approach able to operate at genome-wide scale. CisMiner allows to perform a blind search of CRMs without any prior information about target CRMs nor limitation in the number of motifs. CisMiner tackles the combinatorial complexity of genome-wide cis-regulatory module extraction using a natural representation of motif combinations as itemsets and applying the Top-Down Fuzzy Frequent- Pattern Tree algorithm to identify significant itemsets. Fuzzy technology allows CisMiner to better handle the imprecision and noise inherent to regulatory processes. Results obtained for a set of well-known binding sites in the S. cerevisiae genome show that our method yields highly reliable predictions. Furthermore, CisMiner was also applied to putative in-silico predicted transcription factor binding sites to identify significant combinations in S. cerevisiae and D. melanogaster, proving that our approach can be further applied genome-wide to more complex genomes. CisMiner is freely accesible at: http://genome2.ugr.es/cisminer. CisMiner can be queried for the results presented in this work and can also perform a customized cis-regulatory module prediction on a query set of transcription factor binding sites provided by

  5. Measurement requirements and techniques for degradation studies and lifetime prediction testing of photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Noel, G. T.; Sliemers, F. A.; Derringer, G. C.; Wood, V. E.; Wilkes, K. E.; Gaines, G. B.; Carmichael, D. C.

    1978-01-01

    Tests of weathering and aging behavior are being developed to characterize the degradation and predict the lifetimes of low-cost photovoltaic arrays. Environmental factors which affect array performance include UV radiation, thermal energy, water, oxygen (generally involved in synergistic effects with UV radiation or high temperatures), physical stress, pollutants (oxides of nitrogen, sulfur dioxide and ozone), abrasives and dirt. A survey of photovoltaic array testing has shown the need to establish quantitative correlations between certain measurable properties (carbonyl formation, glass transition temperature, and molecular weight change) and modes of degradation and failure.

  6. Local stimulus disambiguation with global motion filters predicts adaptive surround modulation.

    PubMed

    Dellen, Babette; Torras, Carme

    2013-10-01

    Humans have no problem segmenting different motion stimuli despite the ambiguity of local motion signals. Adaptive surround modulation, i.e., the apparent switching between integrative and antagonistic modes, is assumed to play a crucial role in this process. However, so far motion processing models based on local integration have not been able to provide a unifying explanation for this phenomenon. This motivated us to investigate the problem of local stimulus disambiguation in an alternative and fundamentally distinct motion-processing model which uses global motion filters for velocity computation. Local information is reconstructed at the end of the processing stream through the constructive interference of global signals, i.e., inverse transformations. We show that in this model local stimulus disambiguation can be achieved by means of a novel filter embedded in this architecture. This gives rise to both integrative and antagonistic effects which are in agreement with those observed in psychophysical experiments with humans, providing a functional explanation for effects of motion repulsion.

  7. Molecular deconstruction, detection, and computational prediction of microenvironment-modulated cellular responses to cancer therapeutics

    PubMed Central

    LaBarge, Mark A; Parvin, Bahram; Lorens, James B

    2014-01-01

    The field of bioengineering has pioneered the application of new precision fabrication technologies to model the different geometric, physical or molecular components of tissue microenvironments on solid-state substrata. Tissue engineering approaches building on these advances are used to assemble multicellular mimetic-tissues where cells reside within defined spatial contexts. The functional responses of cells in fabricated microenvironments has revealed a rich interplay between the genome and extracellular effectors in determining cellular phenotypes, and in a number of cases has revealed the dominance of microenvironment over genotype. Precision bioengineered substrata are limited to a few aspects, whereas cell/tissue-derived microenvironments have many undefined components. Thus introducing a computational module may serve to integrate these types of platforms to create reasonable models of drug responses in human tissues. This review discusses how combinatorial microenvironment microarrays and other biomimetic microenvironments have revealed emergent properties of cells in particular microenvironmental contexts, the platforms that can measure phenotypic changes within those contexts, and the computational tools that can unify the microenvironment-imposed functional phenotypes with underlying constellations of proteins and genes. Ultimately we propose that a merger of these technologies will enable more accurate pre-clinical drug discovery. PMID:24582543

  8. Local stimulus disambiguation with global motion filters predicts adaptive surround modulation.

    PubMed

    Dellen, Babette; Torras, Carme

    2013-10-01

    Humans have no problem segmenting different motion stimuli despite the ambiguity of local motion signals. Adaptive surround modulation, i.e., the apparent switching between integrative and antagonistic modes, is assumed to play a crucial role in this process. However, so far motion processing models based on local integration have not been able to provide a unifying explanation for this phenomenon. This motivated us to investigate the problem of local stimulus disambiguation in an alternative and fundamentally distinct motion-processing model which uses global motion filters for velocity computation. Local information is reconstructed at the end of the processing stream through the constructive interference of global signals, i.e., inverse transformations. We show that in this model local stimulus disambiguation can be achieved by means of a novel filter embedded in this architecture. This gives rise to both integrative and antagonistic effects which are in agreement with those observed in psychophysical experiments with humans, providing a functional explanation for effects of motion repulsion. PMID:23685285

  9. Molecular deconstruction, detection, and computational prediction of microenvironment-modulated cellular responses to cancer therapeutics.

    PubMed

    Labarge, Mark A; Parvin, Bahram; Lorens, James B

    2014-04-01

    The field of bioengineering has pioneered the application of new precision fabrication technologies to model the different geometric, physical or molecular components of tissue microenvironments on solid-state substrata. Tissue engineering approaches building on these advances are used to assemble multicellular mimetic-tissues where cells reside within defined spatial contexts. The functional responses of cells in fabricated microenvironments have revealed a rich interplay between the genome and extracellular effectors in determining cellular phenotypes and in a number of cases have revealed the dominance of microenvironment over genotype. Precision bioengineered substrata are limited to a few aspects, whereas cell/tissue-derived microenvironments have many undefined components. Thus, introducing a computational module may serve to integrate these types of platforms to create reasonable models of drug responses in human tissues. This review discusses how combinatorial microenvironment microarrays and other biomimetic microenvironments have revealed emergent properties of cells in particular microenvironmental contexts, the platforms that can measure phenotypic changes within those contexts, and the computational tools that can unify the microenvironment-imposed functional phenotypes with underlying constellations of proteins and genes. Ultimately we propose that a merger of these technologies will enable more accurate pre-clinical drug discovery.

  10. Learned predictiveness training modulates biases towards using boundary or landmark cues during navigation

    PubMed Central

    Buckley, Matthew G.; Smith, Alastair D.; Haselgrove, Mark

    2015-01-01

    A number of navigational theories state that learning about landmark information should not interfere with learning about shape information provided by the boundary walls of an environment. A common test of such theories has been to assess whether landmark information will overshadow, or restrict, learning about shape information. Whilst a number of studies have shown that landmarks are not able to overshadow learning about shape information, some have shown that landmarks can, in fact, overshadow learning about shape information. Given the continued importance of theories that grant the shape information that is provided by the boundary of an environment a special status during learning, the experiments presented here were designed to assess whether the relative salience of shape and landmark information could account for the discrepant results of overshadowing studies. In Experiment 1, participants were first trained that either the landmarks within an arena (landmark-relevant), or the shape information provided by the boundary walls of an arena (shape-relevant), were relevant to finding a hidden goal. In a subsequent stage, when novel landmark and shape information were made relevant to finding the hidden goal, landmarks dominated behaviour for those given landmark-relevant training, whereas shape information dominated behaviour for those given shape-relevant training. Experiment 2, which was conducted without prior relevance training, revealed that the landmark cues, unconditionally, dominated behaviour in our task. The results of the present experiments, and the conflicting results from previous overshadowing experiments, are explained in terms of associative models that incorporate an attention variant. PMID:25409751

  11. Stimulus onset predictability modulates proactive action control in a Go/No-go task

    PubMed Central

    Berchicci, Marika; Lucci, Giuliana; Spinelli, Donatella; Di Russo, Francesco

    2015-01-01

    The aim of the study was to evaluate whether the presence/absence of visual cues specifying the onset of an upcoming, action-related stimulus modulates pre-stimulus brain activity, associated with the proactive control of goal-directed actions. To this aim we asked 12 subjects to perform an equal probability Go/No-go task with four stimulus configurations in two conditions: (1) uncued, i.e., without any external information about the timing of stimulus onset; and (2) cued, i.e., with external visual cues providing precise information about the timing of stimulus onset. During task both behavioral performance and event-related potentials (ERPs) were recorded. Behavioral results showed faster response times in the cued than uncued condition, confirming existing literature. ERPs showed novel results in the proactive control stage, that started about 1 s before the motor response. We observed a slow rising prefrontal positive activity, more pronounced in the cued than the uncued condition. Further, also pre-stimulus activity of premotor areas was larger in cued than uncued condition. In the post-stimulus period, the P3 amplitude was enhanced when the time of stimulus onset was externally driven, confirming that external cueing enhances processing of stimulus evaluation and response monitoring. Our results suggest that different pre-stimulus processing come into play in the two conditions. We hypothesize that the large prefrontal and premotor activities recorded with external visual cues index the monitoring of the external stimuli in order to finely regulate the action. PMID:25964751

  12. Multivariate analysis of factors predicting prostate dose in intensity-modulated radiotherapy

    SciTech Connect

    Tomita, Tsuneyuki; Nakamura, Mitsuhiro; Hirose, Yoshinori; Kitsuda, Kenji; Notogawa, Takuya; Miki, Katsuhito; Nakamura, Kiyonao; Ishigaki, Takashi

    2014-01-01

    We conducted a multivariate analysis to determine relationships between prostate radiation dose and the state of surrounding organs, including organ volumes and the internal angle of the levator ani muscle (LAM), based on cone-beam computed tomography (CBCT) images after bone matching. We analyzed 270 CBCT data sets from 30 consecutive patients receiving intensity-modulated radiation therapy for prostate cancer. With patients in the supine position on a couch with the HipFix system, data for center of mass (COM) displacement of the prostate and the state of individual organs were acquired and compared between planning CT and CBCT scans. Dose distributions were then recalculated based on CBCT images. The relative effects of factors on the variance in COM, dose covering 95% of the prostate volume (D{sub 95%}), and percentage of prostate volume covered by the 100% isodose line (V{sub 100%}) were evaluated by a backward stepwise multiple regression analysis. COM displacement in the anterior-posterior direction (COM{sub AP}) correlated significantly with the rectum volume (δVr) and the internal LAM angle (δθ; R = 0.63). Weak correlations were seen for COM in the left-right (R = 0.18) and superior-inferior directions (R = 0.31). Strong correlations between COM{sub AP} and prostate D{sub 95%} and V{sub 100%} were observed (R ≥ 0.69). Additionally, the change ratios in δVr and δθ remained as predictors of prostate D{sub 95%} and V{sub 100%}. This study shows statistically that maintaining the same rectum volume and LAM state for both the planning CT simulation and treatment is important to ensure the correct prostate dose in the supine position with bone matching.

  13. The modulation of savouring by prediction error and its effects on choice

    PubMed Central

    Iigaya, Kiyohito; Story, Giles W; Kurth-Nelson, Zeb; Dolan, Raymond J; Dayan, Peter

    2016-01-01

    When people anticipate uncertain future outcomes, they often prefer to know their fate in advance. Inspired by an idea in behavioral economics that the anticipation of rewards is itself attractive, we hypothesized that this preference of advance information arises because reward prediction errors carried by such information can boost the level of anticipation. We designed new empirical behavioral studies to test this proposal, and confirmed that subjects preferred advance reward information more strongly when they had to wait for rewards for a longer time. We formulated our proposal in a reinforcement-learning model, and we showed that our model could account for a wide range of existing neuronal and behavioral data, without appealing to ambiguous notions such as an explicit value for information. We suggest that such boosted anticipation significantly drives risk-seeking behaviors, most pertinently in gambling. DOI: http://dx.doi.org/10.7554/eLife.13747.001 PMID:27101365

  14. The Utility of P300 as a Schizophrenia Endophenotype and Predictive Biomarker: Clinical and Socio-Demographic Modulators in COGS-2

    PubMed Central

    Turetsky, Bruce I.; Dress, Erich M.; Braff, David L.; Calkins, Monica E.; Green, Michael F.; Greenwood, Tiffany A.; Gur, Raquel E.; Gur, Ruben C.; Lazzeroni, Laura C.; Nuechterlein, Keith H.; Radant, Allen D.; Seidman, Larry J.; Siever, Larry J.; Silverman, Jeremy M.; Sprock, Joyce; Stone, William S.; Sugar, Catherine A.; Swerdlow, Neal R.; Tsuang, Debby W.; Tsuang, Ming T.; Light, Gregory

    2014-01-01

    Reduced auditory P300 amplitude is a robust schizophrenia deficit exhibiting the qualities of a viable genetic endophenotype. These include heritability, test-retest reliability, and trait-like stability. Recent evidence suggests that P300 may also serve as a predictive biomarker for transition to psychosis during the schizophrenia prodrome. Historically, the utility of the P300 has been limited by its clinical nonspecificity, cross-site measurement variability, and required EEG expertise. The Consortium on the Genetics of Schizophrenia (COGS-2) study provided an opportunity to examine the consistency of the measure across multiple sites with varying degrees of EEG experience, and to identify important modulating factors that contribute to measurement variability. Auditory P300 was acquired from 649 control and 587 patients at 5 sites. An overall patient deficit was observed with effect size 0.62. Each site independently observed a significant patient deficit, but site differences also existed. In patients, site differences reflected clinical differences in positive symptomatology and functional capacity. In controls, site differences reflected differences in racial stratification, smoking and substance use history. These factors differentially suppressed the P300 response, but only in control subjects. This led to an attenuated patient-control difference among smokers and among African Americans with history of substance use. These findings indicate that the P300 can be adequately assessed quantitatively, across sites, without substantial EEG expertise. Measurements are suitable for both genetic endophenotype analyses and studies of psychosis risk and conversion. However, careful attention must be given to selection of appropriate comparison samples to avoid misleading false negative results. PMID:25306203

  15. Modulation of tight junctions does not predict oral absorption of hydrophilic compounds: use of Caco-2 and Calu-3 cells.

    PubMed

    Kamath, Amrita V; Morrison, Richard A; Mathias, Neil R; Dando, Sandra A; Marino, Anthony M; Chong, Saeho

    2007-08-01

    Permeability estimates using Caco-2 cells do not accurately predict the absorption of hydrophilic drugs that are primarily absorbed via the paracellular pathway. The objective of this study was to investigate whether modulation of tight junctions would help differentiation of paracellularly absorbed compounds. Tight junctions in Caco-2 cell monolayers were manipulated using calcium depletion approaches to decrease the transepithelial electrical resistance (TEER) of the monolayers, and permeability of hydrophilic compounds were measured under these conditions. Permeability of these compounds were also measured in Calu-3 cells, which have tighter junctions than Caco-2 cells. Calcium depletion loosened the tight junctions of Caco-2 cells to varying levels as measured by the decrease in TEER values of the monolayers. While the absolute permeability of all the model compounds increased as the tight junctions were loosened, the ratios of their permeability relative to mannitol permeability were similar. The permeability of these compounds in the tighter Calu-3 cells were also found to be similar to each other. Altering the tight junctions of Caco-2 cells to obtain leakier cell monolayers, or using a cell line with tighter junctions like Calu-3 cells, did not improve differentiation between well absorbed and poorly absorbed hydrophilic drugs. Mere manipulation of the tight junctions to increase or decrease transepithelial electrical resistance does not appear to be a viable approach to predict human absorption for hydrophilic compounds that are primarily absorbed via the paracellular pathway.

  16. Analytical and experimental heat transfer and flow-field prediction on a rectangular reentry module

    SciTech Connect

    Laganelli, A.L.

    1980-02-05

    A General Purpose Heat Source (GPHS) has been designed for the purpose of supplying power to a radioisotope thermal generator intended for interplanetary missions. The baseline configuration, nominally 2 in. x 4 in. x 4 in. with sharp edges and corners, is required to survive accidental earth reentry as well as terminal impact velocities. Several problems have been identified relative to survival criteria during reentry. This paper is concerned with the flow field and reentry heating for a broad face-on or side-on reentry orientation. Moreover, the analysis considers convective heat transfer in the absence of roughness or ablation effects during the supersonic/hypersonic regime of reentry. The anaytical results are compared with wind tunnel data. From these studies it was concluded that heat transfer distributions for non-circular shapes ca be obtained for reentry conditions using wind tunnel data for the surface distributions and a stagnation value based on a reference sphere condition. The distributions obtained at a fixed Mach number (M > 1) appear valid over an extended range of Mach numbers. The above required definition of a proper velocity gradient, and definition of an area aspect ratio. Flowfield predictions (inviscid) using the CM2DT program provide a proper definition of pressure and shock characteristics for non-similar (viscous) solutions. (LCL)

  17. Suppression effects in feature-based attention

    PubMed Central

    Wang, Yixue; Miller, James; Liu, Taosheng

    2015-01-01

    Attending to a feature enhances visual processing of that feature, but it is less clear what occurs to unattended features. Single-unit recording studies in middle temporal (MT) have shown that neuronal modulation is a monotonic function of the difference between the attended and neuron's preferred direction. Such a relationship should predict a monotonic suppressive effect in psychophysical performance. However, past research on suppressive effects of feature-based attention has remained inconclusive. We investigated the suppressive effect for motion direction, orientation, and color in three experiments. We asked participants to detect a weak signal among noise and provided a partially valid feature cue to manipulate attention. We measured performance as a function of the offset between the cued and signal feature. We also included neutral trials where no feature cues were presented to provide a baseline measure of performance. Across three experiments, we consistently observed enhancement effects when the target feature and cued feature coincided and suppression effects when the target feature deviated from the cued feature. The exact profile of suppression was different across feature dimensions: Whereas the profile for direction exhibited a “rebound” effect, the profiles for orientation and color were monotonic. These results demonstrate that unattended features are suppressed during feature-based attention, but the exact suppression profile depends on the specific feature. Overall, the results are largely consistent with neurophysiological data and support the feature-similarity gain model of attention. PMID:26067533

  18. Emotional attention capture by facial expressions

    PubMed Central

    Sawada, Reiko; Sato, Wataru

    2015-01-01

    Previous studies have shown that emotional facial expressions capture visual attention. However, it has been unclear whether attentional modulation is attributable to their emotional significance or to their visual features. We investigated this issue using a spatial cueing paradigm in which non-predictive cues were peripherally presented before the target was presented in either the same (valid trial) or the opposite (invalid trial) location. The target was an open dot and the cues were photographs of normal emotional facial expressions of anger and happiness, their anti-expressions and neutral expressions. Anti-expressions contained the amount of visual changes equivalent to normal emotional expressions compared with neutral expressions, but they were usually perceived as emotionally neutral. The participants were asked to localize the target as soon as possible. After the cueing task, they evaluated their subjective emotional experiences to the cue stimuli. Compared with anti-expressions, the normal emotional expressions decreased and increased the reaction times (RTs) in the valid and invalid trials, respectively. Shorter RTs in the valid trials and longer RTs in the invalid trials were related to higher subjective arousal ratings. These results suggest that emotional facial expressions accelerate attentional engagement and prolong attentional disengagement due to their emotional significance. PMID:26365083

  19. Body Mass Index, Modulated by Lateral Posterior Tibial Slope, Predicts ACL Injury Risk

    PubMed Central

    Bojicic, Katherine M.; Beaulieu, Melanie L.; Krieger, Daniel Imaizumi; Ashton-Miller, James A.; Wojtys, Edward M.

    2016-01-01

    Objectives: Intervention strategies to prevent ACL injury rely on increasing knowledge of risk factors. While several modifiable and non-modifiable risk factors for ACL rupture have been identified, the interaction between them remains unknown. The aim of this study was to quantify the relationship between BMI and several knee geometries as potential risk factors for ACL injury. We hypothesized that an increased BMI in the presence of an increased posterior tibial slope or middle cartilage slope would increase risk of ACL injury. We also hypothesized that an increased BMI in the presence of a decreased posterior meniscal height or meniscal bone angle would result in an increased risk of ACL injury. Methods: Sagittal knee MRI files from 76 ACL-injured and 42 non-injured subjects were gathered from the institution’s archive. The PTS, MCS, PMH, and MBA were measured using the circle method and compared with BMI from the subject demographic. Data were analyzed using univariate and multivariate logistical regression. Figure 1 details measurements made for each knee geometry. Results: Univariate analysis of PTS showed increases in PTS significantly increase the odds of ACL tear (p = 0.043, OR =1.12). Univariate analysis of MCS showed increases of MCS significantly increase the odds of ACL tear (p = 0.037, OR = 1.12). Multivariate analysis of PTS and BMI centered around the mean (PTS*cBMI) showed increases of PTS in combination with increases in cBMI significantly increases the odds of ACL rupture (p value = .050, OR = 1.03). Table 1 shows predicted increases in ACL injury risk for combinations of increases in PTS and BMI. Conclusion: An increase in BMI will increase the risk of ACL tear when an increase in lateral posterior tibial slope is present. An increase in lateral posterior tibial slope or lateral middle cartilage slope increases the risk of an ACL tear.

  20. Design of the Health Monitoring System for the Artificial Pancreas: Low Glucose Prediction Module

    PubMed Central

    Harvey, Rebecca A.; Dassau, Eyal; Zisser, Howard; Seborg, Dale E.; Jovanovič, Lois; Doyle, Francis J.

    2012-01-01

    Background The purpose of this study was to design and evaluate a safety system for the artificial pancreas device system (APDS). Safe operation of the APDS is a critical task, where the safety system is engaged only as needed to ensure reliable operation without positive feedback to the controller. Methods The Health Monitoring System (HMS) was designed as a modular system to ensure the safety of the APDS and the user. It was designed using a large set of ambulatory data and evaluated in silico by inducing hypoglycemia with a missed meal [bolus for a 65 g carbohydrate (CHO) meal] and administering rescue CHOs per HMS alerting. The HMS was validated in-clinic with a real-life challenge of a subject who overdosed insulin prior to admission. Results The HMS was evaluated for clinical use with a 15 min prediction horizon. Retrospectively, 93.5% of episodes were detected with 2.9 false alarms per day. During in silico evaluation, the HMS reduced the time spent <70 mg/dl from 15% to 3%. When the HMS was first tested in-clinic, the subject overdosed ~3 U of insulin prior to her arrival to a closed-loop session (against protocol). The controller reduced insulin delivery, and the HMS gave four alerts that were successfully received via clinical software and text and multimedia messages. Even with insulin reduction and CHO supplements, hypoglycemia was unavoidable but manageable due to the HMS, confirming that a safety system to detect adverse events is an essential part of the APDS. Conclusions The ability of the HMS to be an effective alert system that provides a safety layer to the APDS controller has been demonstrated in a clinical setting. PMID:23294779

  1. Animacy-based predictions in language comprehension are robust: contextual cues modulate but do not nullify them.

    PubMed

    Muralikrishnan, R; Schlesewsky, Matthias; Bornkessel-Schlesewsky, Ina

    2015-05-22

    Couldn׳t a humble coconut hurt a gardener? At least in the first instance, the brain seems to assume that it should not: we perceive inanimate entities such as coconuts as poor event instigators ("Actors"). Ideally, entities causing a change in another entity should be animate and this assumption not only influences event perception but also carries over to language comprehension. We present three auditory event-related brain potential (ERP) studies on the processing of inanimate and animate subjects and objects in simple transitive sentences in Tamil. ERP responses were measured at the second argument (event participant) in all three studies. Experiment 1 employed all possible animacy combinations of Actors and Undergoers (affected participants) in Actor- and Undergoer-initial verb-final orders. Experiments 2 and 3 employed a fairly novel context design that enabled us to compare ERPs evoked by identical auditory material to differing contextual expectations: Experiment 2 focussed on constructions in which an inanimate Actor acts upon an inanimate Undergoer, whereas Experiment 3 examined whether and how a preceding context modulates the prediction for an ideal Actor. Results showed an N400 effect when the prediction for an ideal (animate) Actor following an Undergoer was not met, thus further supporting the cross-linguistically robust nature of animacy preferences. In addition, though specific contextual cues that are indicative of a forthcoming non-ideal Actor may reduce this negativity in comparison to when such cues are not available, they nevertheless do not nullify it, suggesting that animacy-based predictions are stronger than contextual cues in online language comprehension.

  2. Alzheimer Disease Cerebrospinal Fluid Biomarkers Moderate Baseline Differences and Predict Longitudinal Change in Attentional Control and Episodic Memory Composites in the Adult Children Study

    PubMed Central

    Aschenbrenner, Andrew J.; Balota, David A.; Fagan, Anne M.; Duchek, Janet M.; Benzinger, Tammie L.S.; Morris, John C.

    2015-01-01

    Objective Cognitive measures that are sensitive to biological markers of Alzheimer disease (AD) pathology are needed in order to (a) facilitate preclinical staging, (b) identify individuals who are at the highest risk for developing clinical symptoms and (c) serve as endpoints for evaluating the efficacy of interventions. The present study assesses the utility of two cognitive composite scores of attentional control and episodic memory as markers for preclinical AD pathology in a group of cognitively normal older adults (N = 238), as part of the Adult Children Study. Method All participants were given a baseline cognitive assessment and follow-up assessments every 3 years over an 8-year period, as well as a lumbar puncture within two years of the initial assessment to collect cerebrospinal fluid (CSF) and a PET-PIB scan for amyloid imaging. Results Results indicated that attentional control was correlated with levels of Aβ42 at the initial assessment whereas episodic memory was not. Longitudinally, individuals with high CSF tau exhibited a decline in both attention and episodic memory over the course of the study. Conclusion These results indicate that measures of attentional control and episodic memory can be utilized to evaluate cognitive decline in preclinical AD and provide support that CSF tau may be a key mechanism driving longitudinal cognitive change. PMID:26416094