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Sample records for saliency switching attention

  1. The Role of Top-Down Focused Spatial Attention in Preattentive Salience Coding and Salience-based Attentional Capture.

    PubMed

    Bertleff, Sabine; Fink, Gereon R; Weidner, Ralph

    2016-08-01

    Selective visual attention requires an efficient coordination between top-down and bottom-up attention control mechanisms. This study investigated the behavioral and neural effects of top-down focused spatial attention on the coding of highly salient distractors and their tendency to capture attention. Combining spatial cueing with an irrelevant distractor paradigm revealed bottom-up based attentional capture only when attention was distributed across the whole search display, including the distractor location. Top-down focusing spatial attention on the target location abolished attentional capture of a salient distractor outside the current attentional focus. Functional data indicated that the missing capture effect was not based on diminished bottom-up salience signals at unattended distractor locations. Irrespectively of whether salient distractors occurred at attended or unattended locations, their presence enhanced BOLD signals at their respective spatial representation in early visual areas as well as in inferior frontal, superior parietal, and medial parietal cortex. Importantly, activity in these regions reflected the presence of a salient distractor rather than attentional capture per se. Moreover, successfully inhibiting attentional capture of a salient distractor at an unattended location further increased neural responses in medial parietal regions known to be involved in controlling spatial attentional shifts. Consequently, data provide evidence that top-down focused spatial attention prevents automatic attentional capture by supporting attentional control processes counteracting a spatial bias toward a salient distractor. PMID:27054402

  2. Fast and Conspicuous? Quantifying Salience With the Theory of Visual Attention

    PubMed Central

    Krüger, Alexander; Tünnermann, Jan; Scharlau, Ingrid

    2016-01-01

    Particular differences between an object and its surrounding cause salience, guide attention, and improve performance in various tasks. While much research has been dedicated to identifying which feature dimensions contribute to salience, much less regard has been paid to the quantitative strength of the salience caused by feature differences. Only a few studies systematically related salience effects to a common salience measure, and they are partly outdated in the light of new findings on the time course of salience effects. We propose Bundesen’s Theory of Visual Attention (TVA) as a theoretical basis for measuring salience and introduce an empirical and modeling approach to link this theory to data retrieved from temporal-order judgments. With this procedure, TVA becomes applicable to a broad range of salience-related stimulus material. Three experiments with orientation pop-out displays demonstrate the feasibility of the method. A 4th experiment substantiates its applicability to the luminance dimension. PMID:27168868

  3. Fast and Conspicuous? Quantifying Salience With the Theory of Visual Attention.

    PubMed

    Krüger, Alexander; Tünnermann, Jan; Scharlau, Ingrid

    2016-01-01

    Particular differences between an object and its surrounding cause salience, guide attention, and improve performance in various tasks. While much research has been dedicated to identifying which feature dimensions contribute to salience, much less regard has been paid to the quantitative strength of the salience caused by feature differences. Only a few studies systematically related salience effects to a common salience measure, and they are partly outdated in the light of new findings on the time course of salience effects. We propose Bundesen's Theory of Visual Attention (TVA) as a theoretical basis for measuring salience and introduce an empirical and modeling approach to link this theory to data retrieved from temporal-order judgments. With this procedure, TVA becomes applicable to a broad range of salience-related stimulus material. Three experiments with orientation pop-out displays demonstrate the feasibility of the method. A 4th experiment substantiates its applicability to the luminance dimension. PMID:27168868

  4. Salience-Based Selection: Attentional Capture by Distractors Less Salient Than the Target

    PubMed Central

    Goschy, Harriet; Müller, Hermann Joseph

    2013-01-01

    Current accounts of attentional capture predict the most salient stimulus to be invariably selected first. However, existing salience and visual search models assume noise in the map computation or selection process. Consequently, they predict the first selection to be stochastically dependent on salience, implying that attention could even be captured first by the second most salient (instead of the most salient) stimulus in the field. Yet, capture by less salient distractors has not been reported and salience-based selection accounts claim that the distractor has to be more salient in order to capture attention. We tested this prediction using an empirical and modeling approach of the visual search distractor paradigm. For the empirical part, we manipulated salience of target and distractor parametrically and measured reaction time interference when a distractor was present compared to absent. Reaction time interference was strongly correlated with distractor salience relative to the target. Moreover, even distractors less salient than the target captured attention, as measured by reaction time interference and oculomotor capture. In the modeling part, we simulated first selection in the distractor paradigm using behavioral measures of salience and considering the time course of selection including noise. We were able to replicate the result pattern we obtained in the empirical part. We conclude that each salience value follows a specific selection time distribution and attentional capture occurs when the selection time distributions of target and distractor overlap. Hence, selection is stochastic in nature and attentional capture occurs with a certain probability depending on relative salience. PMID:23382820

  5. The role of visual saliency for the allocation of attention: Evidence from spatial neglect and hemianopia.

    PubMed

    Fellrath, Julia; Ptak, Radek

    2015-07-01

    Visual scanning and exploration of natural scenes not only depends on specific objects, but also on local features. Models of spatial attention propose that features such as orientation or colour are processed pre-attentively and in parallel. According to these models attention interferes at a later stage, where features are combined into a representation of visual saliency. Saliency is a good predictor of ocular fixations during scanning of static pictures. Here, we tested whether fixations of patients with left spatial neglect, hemianopia, or both can be predicted based on local image content. Participants were asked to freely scan natural images while saccades and ocular fixations were registered. Hemianopic patients produced a similar distribution of fixations and relied similarly on picture saliency as healthy controls. In contrast, neglect patients looked to image regions with increased saliency and higher local orientation and intensity thresholds on the neglected side of space. The reliance on increased saliency during visual exploration was predicted by damage to subcortical regions interconnecting the inferior parietal and lateral premotor cortex. These findings suggest that spatial neglect leads to a combined attentive and pre-attentive deficit in the processing of saliency and feature information. PMID:25956677

  6. Selective Attention and Attention Switching: Towards a Unified Developmental Approach

    ERIC Educational Resources Information Center

    Hanania, Rima; Smith, Linda B.

    2010-01-01

    We review and relate two literatures on the development of attention in children: one concerning flexible attention switching and the other concerning selective attention. The first is a growing literature on preschool children's performances in an attention-switching task indicating that children become more flexible in their attentional control…

  7. Salience and Attention in Surprisal-Based Accounts of Language Processing

    PubMed Central

    Zarcone, Alessandra; van Schijndel, Marten; Vogels, Jorrig; Demberg, Vera

    2016-01-01

    The notion of salience has been singled out as the explanatory factor for a diverse range of linguistic phenomena. In particular, perceptual salience (e.g., visual salience of objects in the world, acoustic prominence of linguistic sounds) and semantic-pragmatic salience (e.g., prominence of recently mentioned or topical referents) have been shown to influence language comprehension and production. A different line of research has sought to account for behavioral correlates of cognitive load during comprehension as well as for certain patterns in language usage using information-theoretic notions, such as surprisal. Surprisal and salience both affect language processing at different levels, but the relationship between the two has not been adequately elucidated, and the question of whether salience can be reduced to surprisal / predictability is still open. Our review identifies two main challenges in addressing this question: terminological inconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalize upon work in visual cognition in order to orient ourselves in surveying the different facets of the notion of salience in linguistics and their relation with models of surprisal. We find that work on salience highlights aspects of linguistic communication that models of surprisal tend to overlook, namely the role of attention and relevance to current goals, and we argue that the Predictive Coding framework provides a unified view which can account for the role played by attention and predictability at different levels of processing and which can clarify the interplay between low and high levels of processes and between predictability-driven expectation and attention-driven focus. PMID:27375525

  8. Salience and Attention in Surprisal-Based Accounts of Language Processing.

    PubMed

    Zarcone, Alessandra; van Schijndel, Marten; Vogels, Jorrig; Demberg, Vera

    2016-01-01

    The notion of salience has been singled out as the explanatory factor for a diverse range of linguistic phenomena. In particular, perceptual salience (e.g., visual salience of objects in the world, acoustic prominence of linguistic sounds) and semantic-pragmatic salience (e.g., prominence of recently mentioned or topical referents) have been shown to influence language comprehension and production. A different line of research has sought to account for behavioral correlates of cognitive load during comprehension as well as for certain patterns in language usage using information-theoretic notions, such as surprisal. Surprisal and salience both affect language processing at different levels, but the relationship between the two has not been adequately elucidated, and the question of whether salience can be reduced to surprisal / predictability is still open. Our review identifies two main challenges in addressing this question: terminological inconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalize upon work in visual cognition in order to orient ourselves in surveying the different facets of the notion of salience in linguistics and their relation with models of surprisal. We find that work on salience highlights aspects of linguistic communication that models of surprisal tend to overlook, namely the role of attention and relevance to current goals, and we argue that the Predictive Coding framework provides a unified view which can account for the role played by attention and predictability at different levels of processing and which can clarify the interplay between low and high levels of processes and between predictability-driven expectation and attention-driven focus. PMID:27375525

  9. Cannabinoid Modulation of Functional Connectivity within Regions Processing Attentional Salience

    PubMed Central

    Bhattacharyya, Sagnik; Falkenberg, Irina; Martin-Santos, Rocio; Atakan, Zerrin; Crippa, Jose A; Giampietro, Vincent; Brammer, Mick; McGuire, Philip

    2015-01-01

    There is now considerable evidence to support the hypothesis that psychotic symptoms are the result of abnormal salience attribution, and that the attribution of salience is largely mediated through the prefrontal cortex, the striatum, and the hippocampus. Although these areas show differential activation under the influence of delta-9-tetrahydrocannabinol (delta-9-THC) and cannabidiol (CBD), the two major derivatives of cannabis sativa, little is known about the effects of these cannabinoids on the functional connectivity between these regions. We investigated this in healthy occasional cannabis users by employing event-related functional magnetic resonance imaging (fMRI) following oral administration of delta-9-THC, CBD, or a placebo capsule. Employing a seed cluster-based functional connectivity analysis that involved using the average time series from each seed cluster for a whole-brain correlational analysis, we investigated the effect of drug condition on functional connectivity between the seed clusters and the rest of the brain during an oddball salience processing task. Relative to the placebo condition, delta-9-THC and CBD had opposite effects on the functional connectivity between the dorsal striatum, the prefrontal cortex, and the hippocampus. Delta-9-THC reduced fronto-striatal connectivity, which was related to its effect on task performance, whereas this connection was enhanced by CBD. Conversely, mediotemporal-prefrontal connectivity was enhanced by delta-9-THC and reduced by CBD. Our results suggest that the functional integration of brain regions involved in salience processing is differentially modulated by single doses of delta-9-THC and CBD and that this relates to the processing of salient stimuli. PMID:25249057

  10. Cannabinoid modulation of functional connectivity within regions processing attentional salience.

    PubMed

    Bhattacharyya, Sagnik; Falkenberg, Irina; Martin-Santos, Rocio; Atakan, Zerrin; Crippa, Jose A; Giampietro, Vincent; Brammer, Mick; McGuire, Philip

    2015-05-01

    There is now considerable evidence to support the hypothesis that psychotic symptoms are the result of abnormal salience attribution, and that the attribution of salience is largely mediated through the prefrontal cortex, the striatum, and the hippocampus. Although these areas show differential activation under the influence of delta-9-tetrahydrocannabinol (delta-9-THC) and cannabidiol (CBD), the two major derivatives of cannabis sativa, little is known about the effects of these cannabinoids on the functional connectivity between these regions. We investigated this in healthy occasional cannabis users by employing event-related functional magnetic resonance imaging (fMRI) following oral administration of delta-9-THC, CBD, or a placebo capsule. Employing a seed cluster-based functional connectivity analysis that involved using the average time series from each seed cluster for a whole-brain correlational analysis, we investigated the effect of drug condition on functional connectivity between the seed clusters and the rest of the brain during an oddball salience processing task. Relative to the placebo condition, delta-9-THC and CBD had opposite effects on the functional connectivity between the dorsal striatum, the prefrontal cortex, and the hippocampus. Delta-9-THC reduced fronto-striatal connectivity, which was related to its effect on task performance, whereas this connection was enhanced by CBD. Conversely, mediotemporal-prefrontal connectivity was enhanced by delta-9-THC and reduced by CBD. Our results suggest that the functional integration of brain regions involved in salience processing is differentially modulated by single doses of delta-9-THC and CBD and that this relates to the processing of salient stimuli. PMID:25249057

  11. An Improved Model of Producing Saliency Map for Visual Attention System

    NASA Astrophysics Data System (ADS)

    Huang, Jingang; Kong, Bin; Cheng, Erkang; Zheng, Fei

    The iLab Neuromorphic Vision Toolkit (iINVT), steadily kept up to date by the group around Laurent Itti, is one of the currently best known attention systems. Their model of bottom up or saliency-based visual attention as well as their implementation serves as a basis for many research groups. How to combine the feature maps finally into the saliency map is a key point for this kind of visual attention system. We modified the original model of Laurent Itti to make it more corresponding with our perception.

  12. The Development of Visual Search in Infancy: Attention to Faces versus Salience

    ERIC Educational Resources Information Center

    Kwon, Mee-Kyoung; Setoodehnia, Mielle; Baek, Jongsoo; Luck, Steven J.; Oakes, Lisa M.

    2016-01-01

    Four experiments examined how faces compete with physically salient stimuli for the control of attention in 4-, 6-, and 8-month-old infants (N = 117 total). Three computational models were used to quantify physical salience. We presented infants with visual search arrays containing a face and familiar object(s), such as shoes and flowers. Six- and…

  13. 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

  14. Salience in Second Language Acquisition: Physical Form, Learner Attention, and Instructional Focus

    PubMed Central

    Cintrón-Valentín, Myrna C.; Ellis, Nick C.

    2016-01-01

    We consider the role of physical form, prior experience, and form focused instruction (FFI) in adult language learning. (1) When presented with competing cues to interpretation, learners are more likely to attend to physically more salient cues in the input. (2) Learned attention is an associative learning phenomenon where prior-learned cues block those that are experienced later. (3) The low salience of morphosyntactic cues can be overcome by FFI, which leads learners to attend cues which might otherwise be ignored. Experiment 1 used eye-tracking to investigate how language background influences learners’ attention to morphological cues, as well as the attentional processes whereby different types of FFI overcome low cue salience, learned attention and blocking. Chinese native speakers (no L1 verb-tense morphology) viewed Latin utterances combining lexical and morphological cues to temporality under control conditions (CCs) and three types of explicit FFI: verb grammar instruction (VG), verb salience with textual enhancement (VS), and verb pretraining (VP), and their use of these cues was assessed in a subsequent comprehension test. CC participants were significantly more sensitive to the adverbs than verb morphology. Instructed participants showed greater sensitivity to the verbs. These results reveal attentional processes whereby learners’ prior linguistic experience can shape their attention toward cues in the input, and whereby FFI helps learners overcome the long-term blocking of verb-tense morphology. Experiment 2 examined the role of modality of input presentation – aural or visual – in L1 English learners’ attentional focus on morphological cues and the effectiveness of different FFI manipulations. CC participants showed greater sensitivity toward the adverb cue. FFI was effective in increasing attention to verb-tense morphology, however, the processing of morphological cues was considerably more difficult under aural presentation. From visual

  15. Salience in Second Language Acquisition: Physical Form, Learner Attention, and Instructional Focus.

    PubMed

    Cintrón-Valentín, Myrna C; Ellis, Nick C

    2016-01-01

    We consider the role of physical form, prior experience, and form focused instruction (FFI) in adult language learning. (1) When presented with competing cues to interpretation, learners are more likely to attend to physically more salient cues in the input. (2) Learned attention is an associative learning phenomenon where prior-learned cues block those that are experienced later. (3) The low salience of morphosyntactic cues can be overcome by FFI, which leads learners to attend cues which might otherwise be ignored. Experiment 1 used eye-tracking to investigate how language background influences learners' attention to morphological cues, as well as the attentional processes whereby different types of FFI overcome low cue salience, learned attention and blocking. Chinese native speakers (no L1 verb-tense morphology) viewed Latin utterances combining lexical and morphological cues to temporality under control conditions (CCs) and three types of explicit FFI: verb grammar instruction (VG), verb salience with textual enhancement (VS), and verb pretraining (VP), and their use of these cues was assessed in a subsequent comprehension test. CC participants were significantly more sensitive to the adverbs than verb morphology. Instructed participants showed greater sensitivity to the verbs. These results reveal attentional processes whereby learners' prior linguistic experience can shape their attention toward cues in the input, and whereby FFI helps learners overcome the long-term blocking of verb-tense morphology. Experiment 2 examined the role of modality of input presentation - aural or visual - in L1 English learners' attentional focus on morphological cues and the effectiveness of different FFI manipulations. CC participants showed greater sensitivity toward the adverb cue. FFI was effective in increasing attention to verb-tense morphology, however, the processing of morphological cues was considerably more difficult under aural presentation. From visual exposure

  16. The role of the collicular pathway in the salience-based progression of visual attention.

    PubMed

    Mizzi, Raphaël; Michael, George A

    2014-08-15

    Visual attention has been shown to progress from the most to the least salient item in a given scene. Cognitive and physiological models assume that this orienting of covert attention relies on the collicular pathway, involving the superior colliculus and the pulvinar. Recent studies questioned this statement as they described attentional capture by visual items invisible to the superior colliculus. Electrophysiological studies shown that there is no direct projections from short-wave receptors to the superior colliculus. S-cone stimuli can thus be employed to assess visual processing without the involvement of the collicular pathway. We have attempted to investigate whether this pathway is involved in the salience-based orientation of attention by presenting S-cone stimuli. Volunteers were asked to make a judgment regarding a target among two distractors (all items of unequal sizes). Items' location and size varied randomly, as well as color, randomly black or calibrated for each subject to activate exclusively S-cones. The hierarchical pattern testifying of the salience-based orientation of attention was only found with black stimuli, arguing in favor of an implication of the collicular pathway in salience. In a second experiment, one item was presented at a time in order to test the item-multiplicity effect by comparing experiments. Performance was the most penalized when presenting multiple stimuli in the black condition. Results were interpreted in terms of distinct modes of processing by the collicular and geniculate pathways. The establishment of salience that determines attentional progression appeared to be only possible when the collicular pathway was solicited. PMID:24880095

  17. Components of attentional set-switching.

    PubMed

    Rushworth, M F S; Passingham, R E; Nobre, A C

    2005-01-01

    A series of distinct event-related potentials (ERPs) have been recorded from the scalp of human subjects as they switch from one task to another. It is possible that task switching may depend on different mechanisms depending on whether the switch requires a change in attentional set, in other words the redirecting of attention to different aspects of a sensory stimulus, or whether it requires a change in intentional set, in others words a change in the way that responses are selected. To address this issue, the current study recorded ERPs while subjects switched between attentional sets and the results were compared with those of a previous investigation in which subjects switched between intentional sets. Subjects selected stimuli according to two conflicting attentional sets, each emphasizing one visual stimulus dimension (colour, shape). Pairs of stimuli, only one of which was to be attended, were presented for between eight and seventeen trials then either a switch or a stay cue was shown. The switch cue instructed subjects to switch from the current attentional set to the other set, while the stay cue instructed subjects to maintain the current set. Comparing ERPs time-locked to the switch and stay cues revealed neural correlates of the initiation of a task switch. Comparing the ERPs time locked to the first stimuli after either stay or switch cues identified neural correlates of the implementation of a task switch. A similar modulation over parietal electrodes was seen when subjects were switching between either attentional or intentional sets. While an intentional set switch began with a medial frontal modulation, attentional set switching began with a lateral frontal modulation. Implementing a new attentional set was associated with modulation of relatively early visual potentials, while implementing a new intentional set was associated with modulation of later response-related potentials. The results confirm that task switching consists of a number of

  18. Video attention deviation estimation using inter-frame visual saliency map analysis

    NASA Astrophysics Data System (ADS)

    Feng, Yunlong; Cheung, Gene; Le Callet, Patrick; Ji, Yusheng

    2012-01-01

    A viewer's visual attention during video playback is the matching of his eye gaze movement to the changing video content over time. If the gaze movement matches the video content (e.g., follow a rolling soccer ball), then the viewer keeps his visual attention. If the gaze location moves from one video object to another, then the viewer shifts his visual attention. A video that causes a viewer to shift his attention often is a "busy" video. Determination of which video content is busy is an important practical problem; a busy video is difficult for encoder to deploy region of interest (ROI)-based bit allocation, and hard for content provider to insert additional overlays like advertisements, making the video even busier. One way to determine the busyness of video content is to conduct eye gaze experiments with a sizable group of test subjects, but this is time-consuming and costineffective. In this paper, we propose an alternative method to determine the busyness of video-formally called video attention deviation (VAD): analyze the spatial visual saliency maps of the video frames across time. We first derive transition probabilities of a Markov model for eye gaze using saliency maps of a number of consecutive frames. We then compute steady state probability of the saccade state in the model-our estimate of VAD. We demonstrate that the computed steady state probability for saccade using saliency map analysis matches that computed using actual gaze traces for a range of videos with different degrees of busyness. Further, our analysis can also be used to segment video into shorter clips of different degrees of busyness by computing the Kullback-Leibler divergence using consecutive motion compensated saliency maps.

  19. Advert saliency distracts children's visual attention during task-oriented internet use

    PubMed Central

    Holmberg, Nils; Sandberg, Helena; Holmqvist, Kenneth

    2014-01-01

    The general research question of the present study was to assess the impact of visually salient online adverts on children's task-oriented internet use. In order to answer this question, an experimental study was constructed in which 9- and 12-year-old Swedish children were asked to solve a number of tasks while interacting with a mockup website. In each trial, web adverts in several saliency conditions were presented. By both measuring children's task accuracy, as well as the visual processing involved in solving these tasks, this study allows us to infer how two types of visual saliency affect children's attentional behavior, and whether such behavioral effects also impacts their task performance. Analyses show that low-level visual features and task relevance in online adverts have different effects on performance measures and process measures respectively. Whereas task performance is stable with regard to several advert saliency conditions, a marked effect is seen on children's gaze behavior. On the other hand, task performance is shown to be more sensitive to individual differences such as age, gender and level of gaze control. The results provide evidence about cognitive and behavioral distraction effects in children's task-oriented internet use caused by visual saliency in online adverts. The experiment suggests that children to some extent are able to compensate for behavioral effects caused by distracting visual stimuli when solving prospective memory tasks. Suggestions are given for further research into the interdiciplinary area between media research and cognitive science. PMID:24575057

  20. Advert saliency distracts children's visual attention during task-oriented internet use.

    PubMed

    Holmberg, Nils; Sandberg, Helena; Holmqvist, Kenneth

    2014-01-01

    The general research question of the present study was to assess the impact of visually salient online adverts on children's task-oriented internet use. In order to answer this question, an experimental study was constructed in which 9- and 12-year-old Swedish children were asked to solve a number of tasks while interacting with a mockup website. In each trial, web adverts in several saliency conditions were presented. By both measuring children's task accuracy, as well as the visual processing involved in solving these tasks, this study allows us to infer how two types of visual saliency affect children's attentional behavior, and whether such behavioral effects also impacts their task performance. Analyses show that low-level visual features and task relevance in online adverts have different effects on performance measures and process measures respectively. Whereas task performance is stable with regard to several advert saliency conditions, a marked effect is seen on children's gaze behavior. On the other hand, task performance is shown to be more sensitive to individual differences such as age, gender and level of gaze control. The results provide evidence about cognitive and behavioral distraction effects in children's task-oriented internet use caused by visual saliency in online adverts. The experiment suggests that children to some extent are able to compensate for behavioral effects caused by distracting visual stimuli when solving prospective memory tasks. Suggestions are given for further research into the interdiciplinary area between media research and cognitive science. PMID:24575057

  1. Altered salience processing in attention deficit hyperactivity disorder.

    PubMed

    Tegelbeckers, Jana; Bunzeck, Nico; Duzel, Emrah; Bonath, Björn; Flechtner, Hans-Henning; Krauel, Kerstin

    2015-06-01

    Attentional problems in patients with attention deficit hyperactivity disorder (ADHD) have often been linked with deficits in cognitive control. Whether these deficits are associated with increased sensitivity to external salient stimuli remains unclear. To address this issue, we acquired functional brain images (fMRI) in 38 boys with and without ADHD (age: 11-16 years). To differentiate the effects of item novelty, contextual rareness and task relevance, participants performed a visual oddball task including four stimulus categories: a frequent standard picture (62.5%), unique novel pictures (12.5%), one repeated rare picture (12.5%), and a target picture (12.5%) that required a specific motor response. As a main finding, we can show considerable overlap in novelty-related BOLD responses between both groups, but only healthy participants showed neural deactivation in temporal as well as frontal regions in response to novel pictures. Furthermore, only ADHD patients, but not healthy controls, engaged wide parts of the novelty network when processing the rare but familiar picture. Our results provide first evidence that ADHD patients show enhanced neural activity in response to novel but behaviorally irrelevant stimuli as well as reduced habituation to familiar items. These findings suggest an inefficient use of neuronal resources in children with ADHD that could be closely linked to increased distractibility. PMID:25648705

  2. 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. PMID:21653585

  3. Visual Attention Allocation Between Robotic Arm and Environmental Process Control: Validating the STOM Task Switching Model

    NASA Technical Reports Server (NTRS)

    Wickens, Christopher; Vieanne, Alex; Clegg, Benjamin; Sebok, Angelia; Janes, Jessica

    2015-01-01

    Fifty six participants time shared a spacecraft environmental control system task with a realistic space robotic arm control task in either a manual or highly automated version. The former could suffer minor failures, whose diagnosis and repair were supported by a decision aid. At the end of the experiment this decision aid unexpectedly failed. We measured visual attention allocation and switching between the two tasks, in each of the eight conditions formed by manual-automated arm X expected-unexpected failure X monitoring- failure management. We also used our multi-attribute task switching model, based on task attributes of priority interest, difficulty and salience that were self-rated by participants, to predict allocation. An un-weighted model based on attributes of difficulty, interest and salience accounted for 96 percent of the task allocation variance across the 8 different conditions. Task difficulty served as an attractor, with more difficult tasks increasing the tendency to stay on task.

  4. Odors enhance the salience of matching images during the attentional blink

    PubMed Central

    Robinson, Amanda K.; Mattingley, Jason B.; Reinhard, Judith

    2013-01-01

    As any food critic knows, the visual presentation of a dish can enhance its aroma. Is the reverse also true? Here we investigated whether odors can enhance the salience of familiar visual objects at the limits of perceptual discrimination, using rapid serial visual presentations (RSVP) to induce an attentional blink (AB). We had participants view RSVP streams containing photographs of odor-related objects (lemon, orange, rose, and mint) amongst non-odor related distractors. In each trial, participants inhaled a single odor, which either matched the odor-related target within the stream (congruent trials), did not match the odor-related target (incongruent trials), or was irrelevant with respect to the target. Congruent odors significantly attenuated the AB for odor-related visual targets, compared with incongruent and irrelevant odors. The findings suggest that familiar odors can render matching visual objects more salient, thereby enhancing their competitive strength at the limits of temporal attention. PMID:24223539

  5. Terror mismanagement: evidence that mortality salience exacerbates attentional bias in social anxiety

    PubMed Central

    Finch, Emma C.; Iverach, Lisa; Menzies, Ross G.; Jones, Mark

    2016-01-01

    ABSTRACT Death anxiety is a basic fear underlying a range of psychological conditions, and has been found to increase avoidance in social anxiety. Given that attentional bias is a core feature of social anxiety, the aim of the present study was to examine the impact of mortality salience (MS) on attentional bias in social anxiety. Participants were 36 socially anxious and 37 non-socially anxious individuals, randomly allocated to a MS or control condition. An eye-tracking procedure assessed initial bias towards, and late-stage avoidance of, socially threatening facial expressions. As predicted, socially anxious participants in the MS condition demonstrated significantly more initial bias to social threat than non-socially anxious participants in the MS condition and socially anxious participants in the control condition. However, this effect was not found for late-stage avoidance of social threat. These findings suggest that reminders of death may heighten initial vigilance towards social threat. PMID:26211552

  6. Saccades, salience and attention: the role of the lateral intraparietal area in visual behavior.

    PubMed

    Goldberg, Michael E; Bisley, James W; Powell, Keith D; Gottlieb, Jacqueline

    2006-01-01

    Neural activity in the lateral intraparietal area (LIP) has been associated with attention to a location in visual space, and with the intention to make saccadic eye movement. In this study we show that neurons in LIP respond to recently flashed task-irrelevant stimuli and saccade targets brought into the receptive field by a saccade, although they respond much to the same stimuli when they are stable in the environment. LIP neurons respond to the appearance of a flashed distractor even when a monkey is planning a memory-guided delayed saccade elsewhere. We then show that a monkey's attention, as defined by an increase in contrast sensitivity, is pinned to the goal of a memory-guided saccade throughout the delay period, unless a distractor appears, in which case attention transiently moves to the site of the distractor and then returns to the goal of the saccade. LIP neurons respond to both the saccade goal and the distractor, and this activity correlates with the monkey's locus of attention. In particular, the activity of LIP neurons predicts when attention migrates from the distractor back to the saccade goal. We suggest that the activity in LIP provides a salience map that is interpreted by the oculomotor system as a saccade goal when a saccade is appropriate, and simultaneously is used by the visual system to determine the locus of attention. PMID:17027387

  7. Cholinergic control over attention in rats prone to attribute incentive salience to reward cues

    PubMed Central

    Paolone, Giovanna; Angelakos, Christopher C.; Meyer, Paul J.; Robinson, Terry E.; Sarter, Martin

    2013-01-01

    Some rats (sign-trackers, ST) are especially prone to attribute incentive salience to reward cues, relative to others (goal-trackers, GT). Thus, reward cues are more likely to promote maladaptive reward-seeking behavior in ST than GT. Here, we asked whether ST and GT differ on another trait that can contribute to poor restraint over behavior evoked by reward cues. We report that, relative to GT, ST have poor control over attentional performance, due in part to insufficient cholinergic stimulation of cortical circuitry. We found that, relative to GT, ST showed poor performance on a sustained attention task (SAT). Furthermore, their performance fluctuated rapidly between periods of good to near-chance performance. This finding was reproduced using a separate cohort of rats. As demonstrated earlier, performance on the SAT was associated with increases in extracellular levels of cortical acetylcholine (ACh); however, SAT performance-associated increases in ACh levels were significantly attenuated in ST relative to GT. Consistent with the view that the modulatory effects of ACh involves stimulation of α4β2* nicotinic acetylcholine receptors (nAChRs), systemic administration of the partial nAChR agonist ABT-089 improved SAT performance in ST and abolished the difference between SAT-associated ACh levels in ST and GT. Neither the nonselective nAChR agonist nicotine nor the psychostimulant amphetamine improved SAT performance. These findings suggest that individuals who have a propensity to attribute high incentive salience to reward cues also exhibit relatively poor attentional control. A combination of these traits may render individuals especially vulnerable to disorders such as obesity and addiction. PMID:23658172

  8. Dissociable effects of salience on attention and goal-directed action.

    PubMed

    Moher, Jeff; Anderson, Brian A; Song, Joo-Hyun

    2015-08-01

    Everyday behavior frequently involves encounters with multiple objects that compete for selection. For example, driving a car requires constant shifts of attention between oncoming traffic, rearview mirrors, and traffic signs and signals, among other objects. Behavioral goals often drive this selection process [1, 2]; however, they are not the sole determinant of selection. Physically salient objects, such as flashing, brightly colored hazard signs, or objects that are salient by virtue of learned associations with reward, such as pictures of food on a billboard, often capture attention regardless of the individual's goals [3-6]. It is typically thought that strongly salient distractor objects capture more attention and are more disruptive than weakly salient distractors [7, 8]. Counterintuitively, though, we found that this is true for perception, but not for goal-directed action. In a visually guided reaching task [9-11], we required participants to reach to a shape-defined target while trying to ignore salient distractors. We observed that strongly salient distractors produced less disruption in goal-directed action than weakly salient distractors. Thus, a strongly salient distractor triggers suppression during goal-directed action, resulting in enhanced efficiency and accuracy of target selection relative to when weakly salient distractors are present. In contrast, in a task requiring no goal-directed action, we found greater attentional interference from strongly salient distractors. Thus, while highly salient stimuli interfere strongly with perceptual processing, increased physical salience or associated value attenuates action-related interference. PMID:26190076

  9. The Roles of Feature-Specific Task Set and Bottom-Up Salience in Attentional Capture: An ERP Study

    ERIC Educational Resources Information Center

    Eimer, Martin; Kiss, Monika; Press, Clare; Sauter, Disa

    2009-01-01

    We investigated the roles of top-down task set and bottom-up stimulus salience for feature-specific attentional capture. Spatially nonpredictive cues preceded search arrays that included a color-defined target. For target-color singleton cues, behavioral spatial cueing effects were accompanied by cue-induced N2pc components, indicative of…

  10. Attention and Memory for Faces and Actions in Infancy: The Salience of Actions over Faces in Dynamic Events.

    ERIC Educational Resources Information Center

    Bahrick, Lorraine E.; Gogate, Lakshmi J.; Ruiz, Ivonne

    2002-01-01

    Three experiments investigated discrimination and memory of 5.5-month-olds for videotapes of women performing different activities (blowing bubbles, brushing hair, brushing teeth) or static displays after a 1-minute and a 7-week delay. Findings demonstrate the attentional salience of actions over faces in dynamic events to 5.5-month-olds. Findings…

  11. Altered intrinsic organisation of brain networks implicated in attentional processes in adult attention-deficit/hyperactivity disorder: a resting-state study of attention, default mode and salience network connectivity.

    PubMed

    Sidlauskaite, Justina; Sonuga-Barke, Edmund; Roeyers, Herbert; Wiersema, Jan R

    2016-06-01

    Deficits in task-related attentional engagement in attention-deficit/hyperactivity disorder (ADHD) have been hypothesised to be due to altered interrelationships between attention, default mode and salience networks. We examined the intrinsic connectivity during rest within and between these networks. Six-minute resting-state scans were obtained. Using a network-based approach, connectivity within and between the dorsal and ventral attention, the default mode and the salience networks was compared between the ADHD and control group. The ADHD group displayed hyperconnectivity between the two attention networks and within the default mode and ventral attention network. The salience network was hypoconnected to the dorsal attention network. There were trends towards hyperconnectivity within the dorsal attention network and between the salience and ventral attention network in ADHD. Connectivity within and between other networks was unrelated to ADHD. Our findings highlight the altered connectivity within and between attention networks, and between them and the salience network in ADHD. One hypothesis to be tested in future studies is that individuals with ADHD are affected by an imbalance between ventral and dorsal attention systems with the former playing a dominant role during task engagement, making individuals with ADHD highly susceptible to distraction by salient task-irrelevant stimuli. PMID:26260900

  12. Electrophysiological Correlates of Aberrant Motivated Attention and Salience Processing in Unaffected Relatives of Schizophrenia Patients.

    PubMed

    Andersen, Elizabeth H; Campbell, Alana M; Schipul, Sarah E; Bellion, Carolyn M; Donkers, Franc C L; Evans, Anna M; Belger, Aysenil

    2016-01-01

    Patients with schizophrenia (SCZ) exhibit debilitating deficits in attention and affective processing, which are often resistant to treatment and associated with poor functional outcomes. Impaired orientation to task-relevant target information has been indexed by diminished P3b event-related potentials in patients, as well as their unaffected first-degree relatives, suggesting that P3b may be a vulnerability marker for schizophrenia. Despite intact affective valence processing, patients are unable to employ cognitive change strategies to reduce electrophysiological responses to aversive stimuli. Less is known about the attentional processing of emotionally salient task-irrelevant information in patients and unaffected first-degree relatives. The goal of the present study was to examine the neural correlates of salience processing, as indexed by the late positive potential (LPP), during the processing of emotionally salient distractor stimuli in 31 patients with SCZ, 28 first-degree relatives, and 47 control participants using an oddball paradigm. Results indicated that despite intact novelty detection (P3a), both SCZ and first-degree relatives demonstrated deficiencies in attentional processing, reflected in attenuated target-P3b, and aberrant motivated attention, with reduced early-LPP amplitudes for aversive stimuli relative to controls. First-degree relatives revealed a unique enhancement of the late-LPP response, possibly underlying an exaggerated evaluation of salient information and a compensatory engagement of neural circuitry. Furthermore, reduced early-LPP and target-P3b amplitudes were associated with enhanced symptom severity. These findings suggest that, in addition to P3b, LPP may be useful for monitoring clinical state. Future studies will explore the value of P3 and LPP responses as vulnerability markers for early detection and prediction of psychopathology. PMID:26251457

  13. The roles of feature-specific task set and bottom-up salience in attentional capture: An ERP study

    PubMed Central

    Eimer, Martin; Kiss, Monika; Press, Clare; Sauter, Disa

    2009-01-01

    We investigated the roles of top-down task set and bottom-up stimulus salience for feature-specific attentional capture. Spatially nonpredictive cues preceded search arrays that included a colour-defined target. For target-colour singleton cues, behavioural spatial cueing effects were accompanied by cue-induced N2pc components, indicative of attentional capture. These effects were only minimally attenuated for non-singleton target-colour cues, underlining the dominance of top-down task over salience set in attentional capture. Nontarget-colour singleton cues triggered no N2pc, but instead an anterior N2 component indicative of top-down inhibition. In Experiment 2, inverted behavioural cueing effects of these cues were accompanied by a delayed N2pc to targets at cued locations, suggesting that perceptually salient but task-irrelevant visual events trigger location-specific inhibition mechanisms which can delay subsequent target selection. PMID:19803639

  14. Neural enhancement and pre-emptive perception: the genesis of attention and the attentional maintenance of the cortical salience map.

    PubMed

    Gee, Angela L; Ipata, Anna E; Gottlieb, Jacqueline; Bisley, James W; Goldberg, Michael E

    2008-01-01

    One of the stable hypotheses in systems neuroscience is the relationship between attention and the enhancement of visual responses when an animal attends to the stimulus in its receptive field (Goldberg and Wurtz, 1972 Journal of Neurophysiology 35 560-574). This was first discovered in the superior colliculus of the monkey: neurons in the superficial layers of the superior colliculus responded more intensely to the onset of a stimulus during blocks of trials in which the monkey had to make a saccade to it than they did during blocks of trials in which the monkey had to continue fixating a central point and not respond to the stimulus. This enhancement has been found in many brain regions, including prefrontal cortex (Boch and Goldberg, 1987 Investigative Ophthalmology 28 Supplement, 124), V4 (Moran and Desimone, 1985 Science 229 782-784), and lateral intraparietal area (Colby et al, 1996 Journal of Neurophysiology 76 2841-2852; Colby and Goldberg, 1999 Annual Review of Neuroscience 22 319-349), and even V1 (Lamme et al, 2000 Vision Research 40 1507-1521). In these studies the assumption has been that the monkey attended to the stimulus because the stimulus evoked an enhanced response. In the experiments described here we show that for abruptly appearing stimuli, attention is not related to the initial response evoked by the stimulus, but by the activity present on the salience map in the parietal cortex when the stimulus appears. Attention to the stimulus may subsequently, by a top down signal, sustain the map, but stimuli can as easily be suppressed by top down features as they can be enhanced. PMID:18491716

  15. Auditory Attention Switching: A Developmental Study.

    ERIC Educational Resources Information Center

    Pearson, Deborah A.; Lane, David M.

    1991-01-01

    Studied the ability of 8- and 11-year olds, and college-age subjects, to allocate attention rapidly. Older subjects were better able to reallocate attention. The developmental change in the reallocation of attention appears to be continuous and quantitative. Improvement is linked to the ability to use active attentional strategies. (Author/GH)

  16. Penetrating the fog of the decoupled mind: the effects of visual salience in the sustained attention to response task.

    PubMed

    Smallwood, Jonathan

    2013-03-01

    An absence of coupling between cognition and perception can mean that the mind neglects the careful processing of information relevant to the task at hand and errors can ensue. Given that highly salient perceptual events can automatically capture attention, the current study explored whether the same neglect of task-relevant information was possible for stimuli with high levels of perceptual saliency (e.g., identifiable by colour). In four experiments, participants performed a go/no-go task with a low frequency of no-go events. Across all experiments, response inhibition was more successful for coloured no-go targets than for stimuli that shared the same colour as the go targets. In addition, the response time (reaction time [RT]) for rare, coloured go targets was slower than when the same events were noncolored. Together, these results suggest that in relatively simple go/no-go tasks, highly salient perceptual events capture attention in an automatic fashion. Increased visual salience is argued to be beneficial when associated with no-go targets because it momentarily enforces coupling between attention and perception, disrupting ongoing behaviour at the precise moment when not responding is the correct action to take. These results suggest that although the mind may at times neglect events in the environment, salient perceptual events cannot be ignored in the same way. PMID:23458549

  17. Selective Attention to Perceptual Dimensions and Switching between Dimensions

    ERIC Educational Resources Information Center

    Meiran, Nachshon; Dimov, Eduard; Ganel, Tzvi

    2013-01-01

    In the present experiments, the question being addressed was whether switching attention between perceptual dimensions and selective attention to dimensions are processes that compete over a common resource? Attention to perceptual dimensions is usually studied by requiring participants to ignore a never-relevant dimension. Selection failure…

  18. The cortical dynamics underlying effective switching of auditory spatial attention

    PubMed Central

    Larson, Eric; Lee, Adrian KC

    2012-01-01

    Successful rapid deployment of attention to relevant sensory stimuli is critical for survival. In a complex environment, attention can be captured by salient events or be deployed volitionally. Furthermore, when multiple events are of interest concurrently, effective interaction with one's surroundings hinges on efficient top-down control of shifting attention. It has been hypothesized that two separate cortical networks coordinate attention shifts across multiple modalities. However, the cortical dynamics of these networks and their behavioral relevance to switching of auditory attention are unknown. Here we show that the strength of each subject's right temporal-parietal junction (RTPJ, part of the ventral network) activation was highly correlated with their behavioral performance in an auditory task. We also provide evidence that the recruitment of the RTPJ likely precedes the right frontal eye fields (FEF; participating in both the dorsal and ventral networks) and middle frontal gyrus (MFG) by around 100 ms when subjects switch their auditory spatial attention. PMID:22974974

  19. Semantic and Affective Salience: The Role of Meaning and Preference in Attentional Capture and Disengagement

    ERIC Educational Resources Information Center

    Biggs, Adam T.; Kreager, Ryan D.; Gibson, Bradley S.; Villano, Michael; Crowell, Charles R.

    2012-01-01

    Emotion appears to have a substantial impact on a wide variety of attentional functions. However, stimuli that elicit affective responses also tend to be meaningful. Here we attempted to disentangle the effects of meaning from the effects of affect on attentional capture by irrelevant distractors. Experiment 1 used a previously unfamiliar…

  20. Semantic and affective salience: the role of meaning and preference in attentional capture and disengagement.

    PubMed

    Biggs, Adam T; Kreager, Ryan D; Gibson, Bradley S; Villano, Michael; Crowell, Charles R

    2012-04-01

    Emotion appears to have a substantial impact on a wide variety of attentional functions. However, stimuli that elicit affective responses also tend to be meaningful. Here we attempted to disentangle the effects of meaning from the effects of affect on attentional capture by irrelevant distractors. Experiment 1 used a previously unfamiliar distractor stimulus, and manipulated the amount of knowledge provided to observers about the distractor. The results suggested that increases in meaning can reduce attentional capture. Experiments 2 and 3 used both familiar and unfamiliar symbols (baseball logos and flags, respectively) as distractors. Critically, of the two familiar symbols, one was rated as affective-positive and the other was rated as affective-negative. As in Experiment 1, the results showed that unfamiliar distractors can capture attention. In addition, the results also suggested that the two affective distractors captured attention (so long as they were sufficiently intense). This finding suggests that while increased knowledge can reduce capture, affect can restore an item's ability to capture attention. Finally, the results of Experiment 4 showed that observers were slower to disengage from a negative item than from a positive item. This evidence emphasizes the differential roles of semantic knowledge versus affect on attentional capture. PMID:22390289

  1. Acute alcohol effects on attentional bias are mediated by subcortical areas associated with arousal and salience attribution.

    PubMed

    Nikolaou, Kyriaki; Field, Matt; Critchley, Hugo; Duka, Theodora

    2013-06-01

    Acute alcohol ingestion increases attentional bias to alcohol-related stimuli; however, the underlying cognitive and brain mechanisms remain unknown. We combined functional magnetic resonance imaging (fMRI) with performance of a dual task that probed attentional distraction by alcohol-related stimuli during 'conflict' processing: the Concurrent Flanker/Alcohol-Attentional bias task (CFAAT). In this task, an Eriksen Flanker task is superimposed on task-unrelated background pictures with alcohol-associated or neutral content. Participants respond to the direction of a central 'target' arrow and ignore adjacent congruent (low cognitive load) or incongruent (high cognitive load) 'flanking' arrows. Using a between-subject design, 40 healthy moderate-to-heavy social drinkers received either no alcohol (placebo), 0.4 g/kg (low dose), or 0.8 g/kg (high dose) of alcohol, and underwent fMRI while performing the CFAAT. The low alcohol dose, relative to placebo, increased response latencies on trials with alcohol-associated backgrounds and, under low cognitive load, increased the activity evoked by these pictures within a medial hypothalamic region. Under high cognitive load, the low alcohol dose, relative to placebo, elicited greater activity within a more lateral hypothalamic region, and reduced activity within frontal motor areas. The high alcohol dose, relative to placebo, did not reliably affect response latencies or neural responses to background images, but reduced overall accuracy under high cognitive load. This effect correlated with changes in reactivity within medial and dorsal prefrontal cortices. These data suggest that alcohol at a low dose primes attentional bias to alcohol-associated stimuli, an effect mediated by activation of subcortical hypothalamic areas implicated in arousal and salience attribution. PMID:23361162

  2. Attentional control of response selection in task switching.

    PubMed

    Schneider, Darryl W

    2015-10-01

    Modulation of cognitive control was investigated by using a proportion congruent manipulation to change response congruency effects in task switching. In an experiment that involved cued switching between semantic categorization tasks, targets were either congruent or incongruent (mapped to the same or different responses across tasks, respectively), and the proportion of congruent targets was manipulated between subjects. Response congruency effects (worse performance for incongruent than for congruent targets) were observed, and they increased with proportion congruent for both response time and error rate. A sequential congruency effect (a smaller response congruency effect following an incongruent than a congruent trial) was observed for error rate, but only for task repetitions. The results suggested top-down control of attention rather than bottom-up control based on item-specific learning, because targets were never repeated during the experiment. Implications for understanding attentional control of response selection in conflict situations are discussed. PMID:26076177

  3. Detection of Visual Events in Underwater Video Using a Neuromorphic Saliency-based Attention System

    NASA Astrophysics Data System (ADS)

    Edgington, D. R.; Walther, D.; Cline, D. E.; Sherlock, R.; Salamy, K. A.; Wilson, A.; Koch, C.

    2003-12-01

    The Monterey Bay Aquarium Research Institute (MBARI) uses high-resolution video equipment on remotely operated vehicles (ROV) to obtain quantitative data on the distribution and abundance of oceanic animals. High-quality video data supplants the traditional approach of assessing the kinds and numbers of animals in the oceanic water column through towing collection nets behind ships. Tow nets are limited in spatial resolution, and often destroy abundant gelatinous animals resulting in species undersampling. Video camera-based quantitative video transects (QVT) are taken through the ocean midwater, from 50m to 4000m, and provide high-resolution data at the scale of the individual animals and their natural aggregation patterns. However, the current manual method of analyzing QVT video by trained scientists is labor intensive and poses a serious limitation to the amount of information that can be analyzed from ROV dives. Presented here is an automated system for detecting marine animals (events) visible in the videos. Automated detection is difficult due to the low contrast of many translucent animals and due to debris ("marine snow") cluttering the scene. Video frames are processed with an artificial intelligence attention selection algorithm that has proven a robust means of target detection in a variety of natural terrestrial scenes. The candidate locations identified by the attention selection module are tracked across video frames using linear Kalman filters. Typically, the occurrence of visible animals in the video footage is sparse in space and time. A notion of "boring" video frames is developed by detecting whether or not there is an interesting candidate object for an animal present in a particular sequence of underwater video -- video frames that do not contain any "interesting" events. If objects can be tracked successfully over several frames, they are stored as potentially "interesting" events. Based on low-level properties, interesting events are

  4. Associative Learning Through Acquired Salience

    PubMed Central

    Treviño, Mario

    2016-01-01

    Most associative learning studies describe the salience of stimuli as a fixed learning-rate parameter. Presumptive saliency signals, however, have also been linked to motivational and attentional processes. An interesting possibility, therefore, is that discriminative stimuli could also acquire salience as they become powerful predictors of outcomes. To explore this idea, we first characterized and extracted the learning curves from mice trained with discriminative images offering varying degrees of structural similarity. Next, we fitted a linear model of associative learning coupled to a series of mathematical representations for stimulus salience. We found that the best prediction, from the set of tested models, was one in which the visual salience depended on stimulus similarity and a non-linear function of the associative strength. Therefore, these analytic results support the idea that the net salience of a stimulus depends both on the items' effective salience and the motivational state of the subject that learns about it. Moreover, this dual salience model can explain why learning about a stimulus not only depends on the effective salience during acquisition but also on the specific learning trajectory that was used to reach this state. Our mathematical description could be instrumental for understanding aberrant salience acquisition under stressful situations and in neuropsychiatric disorders like schizophrenia, obsessive-compulsive disorder, and addiction. PMID:26793078

  5. Associative Learning Through Acquired Salience.

    PubMed

    Treviño, Mario

    2015-01-01

    Most associative learning studies describe the salience of stimuli as a fixed learning-rate parameter. Presumptive saliency signals, however, have also been linked to motivational and attentional processes. An interesting possibility, therefore, is that discriminative stimuli could also acquire salience as they become powerful predictors of outcomes. To explore this idea, we first characterized and extracted the learning curves from mice trained with discriminative images offering varying degrees of structural similarity. Next, we fitted a linear model of associative learning coupled to a series of mathematical representations for stimulus salience. We found that the best prediction, from the set of tested models, was one in which the visual salience depended on stimulus similarity and a non-linear function of the associative strength. Therefore, these analytic results support the idea that the net salience of a stimulus depends both on the items' effective salience and the motivational state of the subject that learns about it. Moreover, this dual salience model can explain why learning about a stimulus not only depends on the effective salience during acquisition but also on the specific learning trajectory that was used to reach this state. Our mathematical description could be instrumental for understanding aberrant salience acquisition under stressful situations and in neuropsychiatric disorders like schizophrenia, obsessive-compulsive disorder, and addiction. PMID:26793078

  6. Switching auditory attention using spatial and non-spatial features recruits different cortical networks

    PubMed Central

    Larson, Eric; Lee, Adrian KC

    2013-01-01

    Switching attention between different stimuli of interest based on particular task demands is important in many everyday settings. In audition in particular, switching attention between different speakers of interest that are talking concurrently is often necessary for effective communication. Recently, it has been shown by multiple studies that auditory selective attention suppresses the representation of unwanted streams in auditory cortical areas in favor of the target stream of interest. However, the neural processing that guides this selective attention process is not well understood. Here we investigated the cortical mechanisms involved in switching attention based on two different types of auditory features. By combining magneto- and electroencephalography (M-EEG) with an anatomical MRI constraint, we examined the cortical dynamics involved in switching auditory attention based on either spatial or pitch features. We designed a paradigm where listeners were cued in the beginning of each trial to switch or maintain attention halfway through the presentation of concurrent target and masker streams. By allowing listeners time to switch during a gap in the continuous target and masker stimuli, we were able to isolate the mechanisms involved in endogenous, top-down attention switching. Our results show a double dissociation between the involvement of right temporoparietal junction (RTPJ) and the left inferior parietal supramarginal part (LIPSP) in tasks requiring listeners to switch attention based on space and pitch features, respectively, suggesting that switching attention based on these features involves at least partially separate processes or behavioral strategies. PMID:24096028

  7. Attention and positive affect: temporal switching or spatial broadening?

    PubMed

    Phaf, R Hans

    2015-04-01

    Evolutionary reasoning and computation suggest that positive affect is associated with higher attentional flexibility than negative affect, even when affectively neutral material is processed. The affective modulation of interference in the Eriksen flanker task seems, however, more readily explained by a spatial broadening of attention due to positive affect. It is argued here that these results should also be interpreted in terms of an increased switching over time between flankers and target (i.e., flexibility). The two hypotheses were contrasted with positive and negative mood inductions in a masked-flanker task. The interval (Stimulus Onset Asynchrony; SOA) with which the masked flankers preceded the target letter was parametrically varied. In contrast to what is found with simultaneous non-masked flanker presentation, masking produced larger interference with negative than with positive moods. In addition, a crossover interaction between mood and SOA emerged. These results seem incompatible with a spatial broadening account and support an affective modulation account in terms of flexibility. PMID:25772099

  8. More Attention to Attention? An Eye-Tracking Investigation of Selection of Perceptual Attributes during a Task Switch

    ERIC Educational Resources Information Center

    Longman, Cai S.; Lavric, Aureliu; Monsell, Stephen

    2013-01-01

    Switching tasks prolongs response times, an effect reduced but not eliminated by active preparation. To explore the role of attentional selection of the relevant stimulus attribute in these task-switch costs, we measured eye fixations in participants cued to identify either a face or a letter displayed on its forehead. With only 200 ms between cue…

  9. More attention to attention? An eye-tracking investigation of selection of perceptual attributes during a task switch.

    PubMed

    Longman, Cai S; Lavric, Aureliu; Monsell, Stephen

    2013-07-01

    Switching tasks prolongs response times, an effect reduced but not eliminated by active preparation. To explore the role of attentional selection of the relevant stimulus attribute in these task-switch costs, we measured eye fixations in participants cued to identify either a face or a letter displayed on its forehead. With only 200 ms between cue and stimulus onsets, the eyes fixated the currently relevant region of the stimulus less and the irrelevant region more on switch than on repeat trials, at stimulus onset and for 500 ms thereafter, in a pattern suggestive of delayed orientation of attention to the relevant region on switch trials. With 800 ms to prepare, both switch costs and inappropriate fixations were reduced, but on switch trials participants still tended (relative to repeat trials) to fixate the now-irrelevant region more at stimulus onset and to maintain fixation on, or refixate, the irrelevant region more during the next 500 ms. The size of this attentional persistence was associated with differences in performance costs between and within participants. We suggest that reorientation of attention is an important, albeit somewhat neglected and controversial, component of advance task-set reconfiguration and that the task-set inertia (or reactivation) to which many attribute the residual task-switch cost seen after preparation includes inertia in (or reactivation of) attentional parameters. PMID:23088543

  10. Cross-Modal Attention-Switching Is Impaired in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Reed, Phil; McCarthy, Julia

    2012-01-01

    This investigation aimed to determine if children with ASD are impaired in their ability to switch attention between different tasks, and whether performance is further impaired when required to switch across two separate modalities (visual and auditory). Eighteen children with ASD (9-13 years old) were compared with 18 typically-developing…

  11. Neural Correlates of Switching Attentional Focus during Finger Movements: An fMRI Study

    PubMed Central

    Zimmermann, Kristin M.; Bischoff, Matthias; Lorey, Britta; Stark, Rudolf; Munzert, Jörn; Zentgraf, Karen

    2012-01-01

    Research on motor-related attentional foci suggests that switching from an internal to an external focus of attention has advantageous effects on motor performance whereas switching from an external to an internal focus has disadvantageous effects. We used functional magnetic resonance imaging to investigate the neural correlates of switching the focus of attention. Two experimental groups were trained to apply one focus direction – internal or external – on a previously learned finger tapping sequence. Participants with an internal focus training were instructed to attend to their moving fingers; those with an external focus training were instructed to attend to the response buttons. In the first half of the experiment, participants performed with their trained focus, in the second half, they were unexpectedly asked to switch to the untrained attentional focus. Our data showed that the switch from a trained internal to an unfamiliar external focus of attention elicited increased activation of the left lateral premotor cortex (PMC). We propose that this activation can be linked to the role of the PMC in action planning – probably indicating a facilitation effect on selectional motor processes. Switching from a trained external to an unfamiliar internal focus of attention revealed enhanced activation of the left primary somatosensory cortex and intraparietal lobule. We interpret these modulations as a result of the amplifying influence of afferent information on motor processing when asked to attend internally in a motor task after being trained with an external focus. PMID:23444053

  12. Binaural beat salience

    PubMed Central

    Grose, John H.; Buss, Emily; Hall, Joseph W.

    2012-01-01

    Previous studies of binaural beats have noted individual variability and response lability, but little attention has been paid to the salience of the binaural beat percept. The purpose of this study was to gauge the strength of the binaural beat percept by matching its salience to that of sinusoidal amplitude modulation (SAM), and to then compare rate discrimination for the two types of fluctuation. Rate discrimination was measured for standard rates of 4, 8, 16, and 32 Hz – all in the 500-Hz carrier region. Twelve normal-hearing adults participated in this study. The results indicated that discrimination acuity for binaural beats is similar to that for SAM tones whose depths of modulation have been adjusted to provide equivalent modulation salience. The matched-salience SAM tones had relatively shallow depths of modulation, suggesting that the perceptual strength of binaural beats is relatively weak, although all listeners perceived them. The Weber fraction for detection of an increase in binaural beat rate is roughly constant across beat rates, at least for rates above 4 Hz, as is rate discrimination for SAM tones. PMID:22326292

  13. Early Development of Subcortical Regions Involved in Non-Cued Attention Switching

    ERIC Educational Resources Information Center

    Casey, B. J.; Davidson, Matthew C.; Hara, Yuko; Thomas, Kathleen M.; Martinez, Antigona; Galvan, Adriana; Halperin, Jeffrey M.; Rodriguez-Aranda, Claudia E.; Tottenham, Nim

    2004-01-01

    This study examined the cognitive and neural development of attention switching using a simple forced-choice attention task and functional magnetic resonance imaging. Fourteen children and adults made discriminations among stimuli based on either shape or color. Performance on these trials was compared to performance during blocked trials…

  14. Does Attention Play a Role in Dynamic Receptive Field Adaptation to Changing Acoustic Salience in A1?

    PubMed Central

    Fritz, Jonathan; Elhilali, Mounya; David, Stephen; Shamma, Shihab

    2007-01-01

    Acoustic filter properties of A1 neurons can dynamically adapt to stimulus statistics, classical conditioning, instrumental learning and the changing auditory attentional focus. We have recently developed an experimental paradigm that allows us to view cortical receptive field plasticity on-line as the animal meets different behavioral challenges by attending to salient acoustic cues and changing its cortical filters to enhance performance. We propose that attention is the key trigger that initiates a cascade of events leading to the dynamic receptive field changes that we observe. In our paradigm, ferrets were initially trained, using conditioned avoidance training techniques, to discriminate between background noise stimuli (temporally orthogonal ripple combinations) and foreground tonal target stimuli. They learned to generalize the task for a wide variety of distinct background and foreground target stimuli. We recorded cortical activity in the awake behaving animal and computed on-line spectrotemporal receptive fields (STRFs) of single neurons in A1. We observed clear, predictable task-related changes in STRF shape while the animal performed spectral tasks (including single tone and multi-tone detection, and two-tone discrimination) with different tonal targets. A different set of task-related changes occurred when the animal performed temporal tasks (including gap detection and click-rate discrimination). Distinctive cortical STRF changes may constitute a “task-specific signature”. These spectral and temporal changes in cortical filters occur quite rapidly, within 2 minutes of task onset, and fade just as quickly after task completion, or in some cases, persisted for hours. The same cell could multiplex by differentially changing its receptive field in different task conditions. On-line dynamic task-related changes, as well as persistent plastic changes, were observed at a single-unit, multi-unit and population level. Auditory attention is likely to be

  15. Intentional attention switching in dichotic listening: exploring the efficiency of nonspatial and spatial selection.

    PubMed

    Lawo, Vera; Fels, Janina; Oberem, Josefa; Koch, Iring

    2014-10-01

    Using an auditory variant of task switching, we examined the ability to intentionally switch attention in a dichotic-listening task. In our study, participants responded selectively to one of two simultaneously presented auditory number words (spoken by a female and a male, one for each ear) by categorizing its numerical magnitude. The mapping of gender (female vs. male) and ear (left vs. right) was unpredictable. The to-be-attended feature for gender or ear, respectively, was indicated by a visual selection cue prior to auditory stimulus onset. In Experiment 1, explicitly cued switches of the relevant feature dimension (e.g., from gender to ear) and switches of the relevant feature within a dimension (e.g., from male to female) occurred in an unpredictable manner. We found large performance costs when the relevant feature switched, but switches of the relevant feature dimension incurred only small additional costs. The feature-switch costs were larger in ear-relevant than in gender-relevant trials. In Experiment 2, we replicated these findings using a simplified design (i.e., only within-dimension switches with blocked dimensions). In Experiment 3, we examined preparation effects by manipulating the cueing interval and found a preparation benefit only when ear was cued. Together, our data suggest that the large part of attentional switch costs arises from reconfiguration at the level of relevant auditory features (e.g., left vs. right) rather than feature dimensions (ear vs. gender). Additionally, our findings suggest that ear-based target selection benefits more from preparation time (i.e., time to direct attention to one ear) than gender-based target selection. PMID:25248101

  16. Cognitive Mechanisms in Chronic Tinnitus: Psychological Markers of a Failure to Switch Attention

    PubMed Central

    Trevis, Krysta J.; McLachlan, Neil M.; Wilson, Sarah J.

    2016-01-01

    The cognitive mechanisms underpinning chronic tinnitus (CT; phantom auditory perceptions) are underexplored but may reflect a failure to switch attention away from a tinnitus sound. Here, we investigated a range of components that influence the ability to switch attention, including cognitive control, inhibition, working memory and mood, on the presence and severity of CT. Our participants with tinnitus showed significant impairments in cognitive control and inhibition as well as lower levels of emotional well-being, compared to healthy-hearing participants. Moreover, the subjective cognitive complaints of tinnitus participants correlated with their emotional well-being whereas complaints in healthy participants correlated with objective cognitive functioning. Combined, cognitive control and depressive symptoms correctly classified 67% of participants. These results demonstrate the core role of cognition in CT. They also provide the foundations for a neurocognitive account of the maintenance of tinnitus, involving impaired interactions between the neurocognitive networks underpinning attention-switching and mood. PMID:27605920

  17. Cognitive Mechanisms in Chronic Tinnitus: Psychological Markers of a Failure to Switch Attention.

    PubMed

    Trevis, Krysta J; McLachlan, Neil M; Wilson, Sarah J

    2016-01-01

    The cognitive mechanisms underpinning chronic tinnitus (CT; phantom auditory perceptions) are underexplored but may reflect a failure to switch attention away from a tinnitus sound. Here, we investigated a range of components that influence the ability to switch attention, including cognitive control, inhibition, working memory and mood, on the presence and severity of CT. Our participants with tinnitus showed significant impairments in cognitive control and inhibition as well as lower levels of emotional well-being, compared to healthy-hearing participants. Moreover, the subjective cognitive complaints of tinnitus participants correlated with their emotional well-being whereas complaints in healthy participants correlated with objective cognitive functioning. Combined, cognitive control and depressive symptoms correctly classified 67% of participants. These results demonstrate the core role of cognition in CT. They also provide the foundations for a neurocognitive account of the maintenance of tinnitus, involving impaired interactions between the neurocognitive networks underpinning attention-switching and mood. PMID:27605920

  18. Relations as Rules: The Role of Attention in the Dimensional Change Card Sort Task

    ERIC Educational Resources Information Center

    Honomichl, Ryan D.; Chen, Zhe

    2011-01-01

    Preschoolers are typically unable to switch sorting rules during the Dimensional Change Card Sort task. One explanation for this phenomenon is attentional inflexibility (Kirkham, Cruess, & Diamond, 2003). In 4 experiments with 3- to 4-year-olds, we tested this hypothesis by examining the influence of dimensional salience on switching performance.…

  19. Task switching in video game players: Benefits of selective attention but not resistance to proactive interference.

    PubMed

    Karle, James W; Watter, Scott; Shedden, Judith M

    2010-05-01

    Research into the perceptual and cognitive effects of playing video games is an area of increasing interest for many investigators. Over the past decade, expert video game players (VGPs) have been shown to display superior performance compared to non-video game players (nVGPs) on a range of visuospatial and attentional tasks. A benefit of video game expertise has recently been shown for task switching, suggesting that VGPs also have superior cognitive control abilities compared to nVGPs. In two experiments, we examined which aspects of task switching performance this VGP benefit may be localized to. With minimal trial-to-trial interference from minimally overlapping task set rules, VGPs demonstrated a task switching benefit compared to nVGPs. However, this benefit disappeared when proactive interference between tasks was increased, with substantial stimulus and response overlap in task set rules. We suggest that VGPs have no generalized benefit in task switching-related cognitive control processes compared to nVGPs, with switch cost reductions due instead to a specific benefit in controlling selective attention. PMID:20064634

  20. Connectionist interpretation of the association between cognitive dissonance and attention switching.

    PubMed

    Matsumoto, Takao

    2014-12-01

    A novel connectionist model accounting for cognitive dissonance is described, in which the concepts of self and attention switching are considered. The model is composed of a unit corresponding to self, a bistable pair comprising two units relevant to two dissonant cognitions, and links whose weights correspond to cognitive evaluations. The model makes it possible to use mathematical formulas to represent the cognitive-dissonance process. Analysis reveals that the model fits experimental data of major paradigms in cognitive dissonance theory. The model shows that attention switching, which is produced by internal and external stimuli, causes building-up of cognitive dissonance and retardation of its reduction. The psychological phenomenon of selective exposure is interpreted on the basis of the operation of the model. PMID:25213757

  1. L-theanine and caffeine improve task switching but not intersensory attention or subjective alertness.

    PubMed

    Einöther, Suzanne J L; Martens, Vanessa E G; Rycroft, Jane A; De Bruin, Eveline A

    2010-04-01

    Tea ingredients L-theanine and caffeine have repeatedly been shown to deliver unique cognitive benefits when consumed in combination. The current randomized, placebo-controlled, double-blind, cross-over study compared a combination of L-theanine (97 mg) and caffeine (40 mg) to a placebo on two attention tasks and a self-report questionnaire before, and 10 and 60 min after consumption. The combination of L-theanine and caffeine significantly improved attention on a switch task as compared to the placebo, while subjective alertness and intersensory attention were not improved significantly. The results support previous evidence that L-theanine and caffeine in combination can improve attention. PMID:20079786

  2. Improving Visual Saliency Computing With Emotion Intensity.

    PubMed

    Liu, Huiying; Xu, Min; Wang, Jinqiao; Rao, Tianrong; Burnett, Ian

    2016-06-01

    Saliency maps that integrate individual feature maps into a global measure of visual attention are widely used to estimate human gaze density. Most of the existing methods consider low-level visual features and locations of objects, and/or emphasize the spatial position with center prior. Recent psychology research suggests that emotions strongly influence human visual attention. In this paper, we explore the influence of emotional content on visual attention. On top of the traditional bottom-up saliency map generation, our saliency map is generated in cooperation with three emotion factors, i.e., general emotional content, facial expression intensity, and emotional object locations. Experiments, carried out on National University of Singapore Eye Fixation (a public eye tracking data set), demonstrate that incorporating emotion does improve the quality of visual saliency maps computed by bottom-up approaches for the gaze density estimation. Our method increases about 0.1 on an average of area under the curve of receiver operation characteristic curve, compared with the four baseline bottom-up approaches (Itti's, attention based on information maximization, saliency using natural, and graph-based vision saliency). PMID:27214350

  3. Shape saliency for remote sensing image

    NASA Astrophysics Data System (ADS)

    Xu, Sheng; Hong, Huo; Fang, Tao; Li, Deren

    2007-11-01

    In this paper, a shape saliency measure for only shape feature of each object in the image is described. Instead biologically-inspired bottom-up Itti model, the dissimilarity is measured by the shape feature. And, Fourier descriptor is used for measuring dissimilarity in this paper. In the model, the object is determined as a salient region, when it is far different from others. Different value of the saliency is ranged to generate a saliency map. It is shown that the attention shift processing can be recorded. Some results from psychological images and remote sensing images are shown and discussed in the paper.

  4. Unified Saliency Detection Model Using Color and Texture Features

    PubMed Central

    Luo, Tiejian

    2016-01-01

    Saliency detection attracted attention of many researchers and had become a very active area of research. Recently, many saliency detection models have been proposed and achieved excellent performance in various fields. However, most of these models only consider low-level features. This paper proposes a novel saliency detection model using both color and texture features and incorporating higher-level priors. The SLIC superpixel algorithm is applied to form an over-segmentation of the image. Color saliency map and texture saliency map are calculated based on the region contrast method and adaptive weight. Higher-level priors including location prior and color prior are incorporated into the model to achieve a better performance and full resolution saliency map is obtained by using the up-sampling method. Experimental results on three datasets demonstrate that the proposed saliency detection model outperforms the state-of-the-art models. PMID:26889826

  5. Good vibrations switch attention: an affective function for network oscillations in evolutionary simulations.

    PubMed

    Heerebout, Bram T; Phaf, R Hans

    2010-05-01

    In the present study, a new hypothesis on the neural mechanisms linking affect to attention was brought forward by evolutionary simulations on agents navigating a virtual environment while collecting food and avoiding predation. The connection strengths between nodes in the networks controlling the agents were subjected to random variation, and the fittest agents were selected for reproduction. Unexpectedly, oscillations of node activations emerged, which drastically enhanced the agent's fitness. We analyzed the mechanisms involved in the modulation of attention and found that oscillations acted on competitive networks. Response selection depended on the connection structure, but the speed and efficacy of switching between selections was modulated by oscillation frequency. The main focus of the present study was the differential emergence of stimulus-specific oscillation frequencies. Oscillations had a higher frequency in an appetitive motivational state than in an aversive state. We suggest that oscillations in biological networks also mediate the affective modulation of attention. PMID:20498346

  6. Dopamine and cognitive control: sex-by-genotype interactions influence the capacity to switch attention.

    PubMed

    Gurvich, C; Rossell, S L

    2015-03-15

    Cognitive performance in healthy persons varies widely between individuals. Sex differences in cognition are well reported, and there is an emerging body of evidence suggesting that the relationship between dopaminergic neurotransmission, implicated in many cognitive functions, is modulated by sex. Here, we examine the influence of sex and genetic variations along the dopaminergic pathway on aspects of cognitive control. A total of 415 healthy individuals, selected from an international consortium linked to Brain Research and Integrative Neuroscience Network (BRAINnet), were genotyped for two common and functional genetic variations of dopamine regulating genes: the catechol-O-methyltransferase [COMT] gene (rs4680) and the dopamine receptor D2 [DRD2] gene (rs6277). Cognitive measures were selected to explore sustained attention (using a continuous performance task), switching of attention (using a Trails B adaptation) and working memory (a visual computerised adaptation of digit span). While there were no main effects for genotype across any tasks, analyses revealed significant sex by genotype interactions for the capacity to switch attention. In relation to COMT, superior performance was noted in females with the Val/Val genotype and for DRD2, superior performance was seen for TT females and CC males. These findings highlight the importance of considering genetic variation in baseline dopamine levels in addition to sex, when considering the impact of dopamine on cognition in healthy populations. These findings also have important implications for the many neuropsychiatric disorders that implicate dopamine, cognitive changes and sex differences. PMID:25510197

  7. Neuro-Oscillatory Mechanisms of Intersensory Selective Attention and Task Switching in School-Aged Children, Adolescents and Young Adults

    ERIC Educational Resources Information Center

    Murphy, Jeremy W.; Foxe, John J.; Molholm, Sophie

    2016-01-01

    The ability to attend to one among multiple sources of information is central to everyday functioning. Just as central is the ability to switch attention among competing inputs as the task at hand changes. Such processes develop surprisingly slowly, such that even into adolescence, we remain slower and more error prone at switching among tasks…

  8. Individuals with Asperger's Disorder Exhibit Difficulty in Switching Attention from a Local Level to a Global Level

    ERIC Educational Resources Information Center

    Katagiri, Masatoshi; Kasai, Tetsuko; Kamio, Yoko; Murohashi, Harumitsu

    2013-01-01

    The purpose of the present study was to determine whether individuals with Asperger's disorder exhibit difficulty in switching attention from a local level to a global level. Eleven participants with Asperger's disorder and 11 age- and gender-matched healthy controls performed a level-repetition switching task using Navon-type hierarchical…

  9. Visual saliency computations: mechanisms, constraints, and the effect of feedback.

    PubMed

    Soltani, Alireza; Koch, Christof

    2010-09-22

    The primate visual system continuously selects spatial proscribed regions, features or objects for further processing. These selection mechanisms--collectively termed selective visual attention--are guided by intrinsic, bottom-up and by task-dependent, top-down signals. While much psychophysical research has shown that overt and covert attention is partially allocated based on saliency-driven exogenous signals, it is unclear how this is accomplished at the neuronal level. Recent electrophysiological experiments in monkeys point to the gradual emergence of saliency signals when ascending the dorsal visual stream and to the influence of top-down attention on these signals. To elucidate the neural mechanisms underlying these observations, we construct a biologically plausible network of spiking neurons to simulate the formation of saliency signals in different cortical areas. We find that saliency signals are rapidly generated through lateral excitation and inhibition in successive layers of neural populations selective to a single feature. These signals can be improved by feedback from a higher cortical area that represents a saliency map. In addition, we show how top-down attention can affect the saliency signals by disrupting this feedback through its action on the saliency map. While we find that saliency computations require dominant slow NMDA currents, the signal rapidly emerges from successive regions of the network. In conclusion, using a detailed spiking network model we find biophysical mechanisms and limitations of saliency computations which can be tested experimentally. PMID:20861387

  10. Two attentional deficits in serial target search: the visual attentional blink and an amodal task-switch deficit.

    PubMed

    Potter, M C; Chun, M M; Banks, B S; Muckenhoupt, M

    1998-07-01

    When monitoring a rapid serial visual presentation at 100 ms per item for 2 targets among distractors, viewers have difficulty reporting the 2nd target (T2) when it appears 200-500 ms after the onset of the 1st letter target (T1): an attentional blink (AB; M. M. Chun & M. C. Potter, 1995b; J. E. Raymond, K. L. Shapiro, & K. M. Arnell, 1992). Does the same deficit occur with auditory search? The authors compared search for auditory, visual, and cross-modal targets in 2 tasks: (a) identifying 2 target letters among digits (Experiments 1-3 and 5) or digits among letters (Experiment 6), and (b) identifying 1 digit among letters and deciding whether an X occurred among the subsequent letters (Experiment 4). In the experiments using the 1st task, the standard AB was found only when both targets were visual. In the 2nd task, with a change in selective set from T1 to T2, a task-switching deficit was obtained regardless of target modality. PMID:9699304

  11. Individuals with Asperger's disorder exhibit difficulty in switching attention from a local level to a global level.

    PubMed

    Katagiri, Masatoshi; Kasai, Tetsuko; Kamio, Yoko; Murohashi, Harumitsu

    2013-02-01

    The purpose of the present study was to determine whether individuals with Asperger's disorder exhibit difficulty in switching attention from a local level to a global level. Eleven participants with Asperger's disorder and 11 age- and gender-matched healthy controls performed a level-repetition switching task using Navon-type hierarchical stimuli. In both groups, level-repetition was beneficial at both levels. Furthermore, individuals with Asperger's disorder exhibited difficulty in switching attention from a local level to a global level compared to control individuals. These findings suggested that there is a problem with the inhibitory mechanism that influences the output of enhanced local visual processing in Asperger's disorder. PMID:22729383

  12. Automatic shifts of attention in the Dimensional Change Card Sort task: subtle changes in task materials lead to flexible switching.

    PubMed

    Fisher, Anna V

    2011-01-01

    Two experiments tested a hypothesis that reducing demands on executive control in a Dimensional Change Card Sort task will lead to improved performance in 3-year-olds. In Experiment 1, the shape dimension was represented by two dissimilar values (stars and flowers), and the color dimension was represented by two similar values (red and pink). This configuration of stimuli rendered shape more salient than color. In Experiment 2, attentional weights of each dimension value were manipulated by using two versus four values to represent the dimensions of shape and color. The results indicated that increasing saliency of the postswitch dimension (Experiment 1) and reducing attentional weights of individual dimension values (Experiment 2) lead to a marked improvement in the postswitch sorting accuracy in 3-year-olds. PMID:20674930

  13. Attention Switching and Multimedia Learning: The Impact of Executive Resources on the Integrative Comprehension of Texts and Pictures

    ERIC Educational Resources Information Center

    Baadte, Christiane; Rasch, Thorsten; Honstein, Helena

    2015-01-01

    The ability to flexibly allocate attention to goal-relevant information is pivotal for the completion of high-level cognitive processes. For instance, in comprehending illustrated texts, the reader permanently has to switch the attentional focus between the text and the corresponding picture in order to extract relevant information from both…

  14. Object recognition with hierarchical discriminant saliency networks.

    PubMed

    Han, Sunhyoung; Vasconcelos, Nuno

    2014-01-01

    The benefits of integrating attention and object recognition are investigated. While attention is frequently modeled as a pre-processor for recognition, we investigate the hypothesis that attention is an intrinsic component of recognition and vice-versa. This hypothesis is tested with a recognition model, the hierarchical discriminant saliency network (HDSN), whose layers are top-down saliency detectors, tuned for a visual class according to the principles of discriminant saliency. As a model of neural computation, the HDSN has two possible implementations. In a biologically plausible implementation, all layers comply with the standard neurophysiological model of visual cortex, with sub-layers of simple and complex units that implement a combination of filtering, divisive normalization, pooling, and non-linearities. In a convolutional neural network implementation, all layers are convolutional and implement a combination of filtering, rectification, and pooling. The rectification is performed with a parametric extension of the now popular rectified linear units (ReLUs), whose parameters can be tuned for the detection of target object classes. This enables a number of functional enhancements over neural network models that lack a connection to saliency, including optimal feature denoising mechanisms for recognition, modulation of saliency responses by the discriminant power of the underlying features, and the ability to detect both feature presence and absence. In either implementation, each layer has a precise statistical interpretation, and all parameters are tuned by statistical learning. Each saliency detection layer learns more discriminant saliency templates than its predecessors and higher layers have larger pooling fields. This enables the HDSN to simultaneously achieve high selectivity to target object classes and invariance. The performance of the network in saliency and object recognition tasks is compared to those of models from the biological and

  15. Object recognition with hierarchical discriminant saliency networks

    PubMed Central

    Han, Sunhyoung; Vasconcelos, Nuno

    2014-01-01

    The benefits of integrating attention and object recognition are investigated. While attention is frequently modeled as a pre-processor for recognition, we investigate the hypothesis that attention is an intrinsic component of recognition and vice-versa. This hypothesis is tested with a recognition model, the hierarchical discriminant saliency network (HDSN), whose layers are top-down saliency detectors, tuned for a visual class according to the principles of discriminant saliency. As a model of neural computation, the HDSN has two possible implementations. In a biologically plausible implementation, all layers comply with the standard neurophysiological model of visual cortex, with sub-layers of simple and complex units that implement a combination of filtering, divisive normalization, pooling, and non-linearities. In a convolutional neural network implementation, all layers are convolutional and implement a combination of filtering, rectification, and pooling. The rectification is performed with a parametric extension of the now popular rectified linear units (ReLUs), whose parameters can be tuned for the detection of target object classes. This enables a number of functional enhancements over neural network models that lack a connection to saliency, including optimal feature denoising mechanisms for recognition, modulation of saliency responses by the discriminant power of the underlying features, and the ability to detect both feature presence and absence. In either implementation, each layer has a precise statistical interpretation, and all parameters are tuned by statistical learning. Each saliency detection layer learns more discriminant saliency templates than its predecessors and higher layers have larger pooling fields. This enables the HDSN to simultaneously achieve high selectivity to target object classes and invariance. The performance of the network in saliency and object recognition tasks is compared to those of models from the biological and

  16. Relationships between trait impulsivity and cognitive control: the effect of attention switching on response inhibition and conflict resolution.

    PubMed

    Leshem, Rotem

    2016-02-01

    This study examined the relationship between trait impulsivity and cognitive control, as measured by the Barratt Impulsiveness Scale (BIS) and a focused attention dichotic listening to words task, respectively. In the task, attention was manipulated in two attention conditions differing in their cognitive control demands: one in which attention was directed to one ear at a time for a whole block of trials (blocked condition) and another in which attention was switched pseudo-randomly between the two ears from trial to trial (mixed condition). Results showed that high impulsivity participants exhibited more false alarm and intrusion errors as well as a lesser ability to distinguish between stimuli in the mixed condition, as compared to low impulsivity participants. In the blocked condition, the performance levels of the two groups were comparable with respect to these measures. In addition, total BIS scores were correlated with intrusions and laterality index in the mixed but not the blocked condition. The findings suggest that high impulsivity individuals may be less prone to attentional difficulties when cognitive load is relatively low. In contrast, when attention switching is involved, high impulsivity is associated with greater difficulty in inhibiting responses and resolving cognitive conflict than is low impulsivity, as reflected in error-prone information processing. The conclusion is that trait impulsivity in a non-clinical population is manifested more strongly when attention switching is required than during maintained attention. This may have important implications for the conceptualization and treatment of impulsivity in both non-clinical and clinical populations. PMID:26245649

  17. MPEG-4 AVC saliency map computation

    NASA Astrophysics Data System (ADS)

    Ammar, M.; Mitrea, M.; Hasnaoui, M.

    2014-02-01

    A saliency map provides information about the regions inside some visual content (image, video, ...) at which a human observer will spontaneously look at. For saliency maps computation, current research studies consider the uncompressed (pixel) representation of the visual content and extract various types of information (intensity, color, orientation, motion energy) which are then fusioned. This paper goes one step further and computes the saliency map directly from the MPEG-4 AVC stream syntax elements with minimal decoding operations. In this respect, an a-priori in-depth study on the MPEG-4 AVC syntax elements is first carried out so as to identify the entities appealing the visual attention. Secondly, the MPEG-4 AVC reference software is completed with software tools allowing the parsing of these elements and their subsequent usage in objective benchmarking experiments. This way, it is demonstrated that an MPEG-4 saliency map can be given by a combination of static saliency and motion maps. This saliency map is experimentally validated under a robust watermarking framework. When included in an m-QIM (multiple symbols Quantization Index Modulation) insertion method, PSNR average gains of 2.43 dB, 2.15dB, and 2.37 dB are obtained for data payload of 10, 20 and 30 watermarked blocks per I frame, i.e. about 30, 60, and 90 bits/second, respectively. These quantitative results are obtained out of processing 2 hours of heterogeneous video content.

  18. Biologically Inspired Object Tracking Using Center-Surround Saliency Mechanisms.

    PubMed

    Mahadevan, Vijay; Vasconcelos, Nuno

    2013-03-01

    A biologically inspired discriminant object tracker is proposed. It is argued that discriminant tracking is a consequence of top-down tuning of the saliency mechanisms that guide the deployment of visual attention. The principle of discriminant saliency is then used to derive a tracker that implements a combination of center-surround saliency, a spatial spotlight of attention, and feature-based attention. In this framework, the tracking problem is formulated as one of continuous target-background classification, implemented in two stages. The first, or learning stage, combines a focus of attention (FoA) mechanism, and bottom-up saliency to identify a maximally discriminant set of features for target detection. The second, or detection stage, uses a feature-based attention mechanism and a target-tuned top-down discriminant saliency detector to detect the target. Overall, the tracker iterates between learning discriminant features from the target location in a video frame and detecting the location of the target in the next. The statistics of natural images are exploited to derive an implementation which is conceptually simple and computationally efficient. The saliency formulation is also shown to establish a unified framework for classifier design, target detection, automatic tracker initialization, and scale adaptation. Experimental results show that the proposed discriminant saliency tracker outperforms a number of state-of-the-art trackers in the literature. PMID:22529325

  19. Neuro-oscillatory mechanisms of intersensory selective attention and task switching in school-aged children, adolescents and young adults.

    PubMed

    Murphy, Jeremy W; Foxe, John J; Molholm, Sophie

    2016-05-01

    The ability to attend to one among multiple sources of information is central to everyday functioning. Just as central is the ability to switch attention among competing inputs as the task at hand changes. Such processes develop surprisingly slowly, such that even into adolescence, we remain slower and more error prone at switching among tasks compared to young adults. The amplitude of oscillations in the alpha band (~8-14 Hz) tracks the top-down deployment of attention, and there is growing evidence that alpha can act as a suppressive mechanism to bias attention away from distracting sensory input. Moreover, the amplitude of alpha has also been shown to be sensitive to the demands of switching tasks. To understand the neural basis of protracted development of these executive functions, we recorded high-density electrophysiology from school-aged children (8-12 years), adolescents (13-17), and young adults (18-34) as they performed a cued inter-sensory selective attention task. The youngest participants showed increased susceptibility to distracting inputs that was especially evident when switching tasks. Concordantly, they showed weaker and delayed onset of alpha modulation compared to the older groups. Thus the flexible and efficient deployment of alpha to bias competition among attentional sets remains underdeveloped in school-aged children. PMID:26190204

  20. DISC: Deep Image Saliency Computing via Progressive Representation Learning.

    PubMed

    Chen, Tianshui; Lin, Liang; Liu, Lingbo; Luo, Xiaonan; Li, Xuelong

    2016-06-01

    Salient object detection increasingly receives attention as an important component or step in several pattern recognition and image processing tasks. Although a variety of powerful saliency models have been intensively proposed, they usually involve heavy feature (or model) engineering based on priors (or assumptions) about the properties of objects and backgrounds. Inspired by the effectiveness of recently developed feature learning, we provide a novel deep image saliency computing (DISC) framework for fine-grained image saliency computing. In particular, we model the image saliency from both the coarse-and fine-level observations, and utilize the deep convolutional neural network (CNN) to learn the saliency representation in a progressive manner. In particular, our saliency model is built upon two stacked CNNs. The first CNN generates a coarse-level saliency map by taking the overall image as the input, roughly identifying saliency regions in the global context. Furthermore, we integrate superpixel-based local context information in the first CNN to refine the coarse-level saliency map. Guided by the coarse saliency map, the second CNN focuses on the local context to produce fine-grained and accurate saliency map while preserving object details. For a testing image, the two CNNs collaboratively conduct the saliency computing in one shot. Our DISC framework is capable of uniformly highlighting the objects of interest from complex background while preserving well object details. Extensive experiments on several standard benchmarks suggest that DISC outperforms other state-of-the-art methods and it also generalizes well across data sets without additional training. The executable version of DISC is available online: http://vision.sysu.edu.cn/projects/DISC. PMID:26742147

  1. The coupling between spatial attention and other components of task-set: A task-switching investigation.

    PubMed

    Longman, Cai S; Lavric, Aureliu; Monsell, Stephen

    2016-11-01

    Is spatial attention reconfigured independently of, or in tandem with, other task-set components when the task changes? We tracked the eyes of participants cued to perform one of three digit-classification tasks, each consistently associated with a distinct location. Previously we observed, on task switch trials, a substantial delay in orientation to the task-relevant location and tendency to fixate the location of the previously relevant task-"attentional inertia". In the present experiments the cues specified (and instructions emphasized) the relevant location rather than the current task. In Experiment 1, with explicit spatial cues (arrows or spatial adverbs), the previously documented attentional handicaps all but disappeared, whilst the performance "switch cost" increased. Hence, attention can become decoupled from other aspects of task-set, but at a cost to the efficacy of task-set preparation. Experiment 2 used arbitrary single-letter cues with instructions and a training regime that encouraged participants to interpret the cue as indicating the relevant location rather than task. As in our previous experiments, and unlike in Experiment 1, we now observed clear switch-induced attentional delay and inertia, suggesting that the natural tendency is for spatial attention and task-set to be coupled and that only quasi-exogenous location cues decouple their reconfiguration. PMID:27033987

  2. A proto-object-based computational model for visual saliency.

    PubMed

    Yanulevskaya, Victoria; Uijlings, Jasper; Geusebroek, Jan-Mark; Sebe, Nicu; Smeulders, Arnold

    2013-01-01

    State-of-the-art bottom-up saliency models often assign high saliency values at or near high-contrast edges, whereas people tend to look within the regions delineated by those edges, namely the objects. To resolve this inconsistency, in this work we estimate saliency at the level of coherent image regions. According to object-based attention theory, the human brain groups similar pixels into coherent regions, which are called proto-objects. The saliency of these proto-objects is estimated and incorporated together. As usual, attention is given to the most salient image regions. In this paper we employ state-of-the-art computer vision techniques to implement a proto-object-based model for visual attention. Particularly, a hierarchical image segmentation algorithm is used to extract proto-objects. The two most powerful ways to estimate saliency, rarity-based and contrast-based saliency, are generalized to assess the saliency at the proto-object level. The rarity-based saliency assesses if the proto-object contains rare or outstanding details. The contrast-based saliency estimates how much the proto-object differs from the surroundings. However, not all image regions with high contrast to the surroundings attract human attention. We take this into account by distinguishing between external and internal contrast-based saliency. Where the external contrast-based saliency estimates the difference between the proto-object and the rest of the image, the internal contrast-based saliency estimates the complexity of the proto-object itself. We evaluate the performance of the proposed method and its components on two challenging eye-fixation datasets (Judd, Ehinger, Durand, & Torralba, 2009; Subramanian, Katti, Sebe, Kankanhalli, & Chua, 2010). The results show the importance of rarity-based and both external and internal contrast-based saliency in fixation prediction. Moreover, the comparison with state-of-the-art computational models for visual saliency demonstrates the

  3. Testing Saliency Parameters for Automatic Target Recognition

    NASA Technical Reports Server (NTRS)

    Pandya, Sagar

    2012-01-01

    A bottom-up visual attention model (the saliency model) is tested to enhance the performance of Automated Target Recognition (ATR). JPL has developed an ATR system that identifies regions of interest (ROI) using a trained OT-MACH filter, and then classifies potential targets as true- or false-positives using machine-learning techniques. In this project, saliency is used as a pre-processing step to reduce the space for performing OT-MACH filtering. Saliency parameters, such as output level and orientation weight, are tuned to detect known target features. Preliminary results are promising and future work entails a rigrous and parameter-based search to gain maximum insight about this method.

  4. Dissociating valuation and saliency signals during decision-making.

    PubMed

    Litt, Ab; Plassmann, Hilke; Shiv, Baba; Rangel, Antonio

    2011-01-01

    There is a growing consensus that the brain computes value and saliency-like signals at the time of decision-making. Value signals are essential for making choices. Saliency signals are related to motivation, attention, and arousal. Unfortunately, an unequivocal characterization of the areas involved in these 2 distinct sets of processes is made difficult by the fact that, in most experiments, both types of signals are highly correlated. We dissociated value and saliency signals using a novel human functional magnetic resonance imaging decision-making task. Activity in the medial orbitofrontal, rostral anterior cingulate, and posterior cingulate cortices was modulated by value but not saliency. The opposite was true for dorsal anterior cingulate, supplementary motor area, insula, and the precentral and fusiform gyri. Only the ventral striatum and the cuneus were modulated by both value and saliency. PMID:20444840

  5. Combination and Switching of Stimulants in Children and Adolescents with Attention Deficit/Hyperactivity Disorder in Quebec

    PubMed Central

    Ben Amor, Leila; Sikirica, Vanja; Cloutier, Martin; Lachaine, Jean; Guerin, Annie; Carter, Valerie; Hodgkins, Paul; van Stralen, Judy

    2014-01-01

    Objective: To assess the one-year period prevalence of stimulant combination therapy and switching in children/ adolescents with attention deficit/hyperactivity disorder (ADHD) in Quebec, Canada. Method: Patients aged 6–17 years, with at least two ADHD diagnosis codes documented in different visits and at least 30 days’ supply of a stimulant during their most recent one-year observation period were selected from the Regie de l’assurance maladie du Quebec database (03/2007–02/2012). Combination therapy was defined as at least 30 consecutive days of concomitant use of multiple stimulants with different active moieties, or use of a stimulant and another psychotropic medication. Therapy switching was defined as a prescription claim for a new psychotropic medication less than 30 days before or after the end of supply of a stimulant. The one-year period prevalence of therapy combination and switching was calculated. Results: The one-year period prevalence of combination therapy and switching among 9,431 children and adolescents with ADHD treated with stimulants was 19.8% and 18.7%, respectively. The most frequent combination categories were atypical antipsychotics (AAP: 10.8%), atomoxetine (ATX: 5.5%) and clonidine (5.3%). The most frequent switched-to categories were other stimulants (7.9%), AAP (5.5%) and ATX (4.7%). Conclusions: Approximately one in five children/adolescents with ADHD on a stimulant experienced combination therapy or therapy switching; however, the majority of the medications used in combination or switching were not label-indicated for the treatment of ADHD in Canada. These results highlight the need for further research to evaluate the risk-benefit of stimulant combination and switching in children and adolescents with ADHD. PMID:25320609

  6. Saliency computation via whitened frequency band selection.

    PubMed

    Lv, Qi; Wang, Bin; Zhang, Liming

    2016-06-01

    Many saliency computational models have been proposed to simulate bottom-up visual attention mechanism of human visual system. However, most of them only deal with certain kinds of images or aim at specific applications. In fact, human beings have the ability to correctly select attentive focuses of objects with arbitrary sizes within any scenes. This paper proposes a new bottom-up computational model from the perspective of frequency domain based on the biological discovery of non-Classical Receptive Field (nCRF) in the retina. A saliency map can be obtained according to the idea of Extended Classical Receptive Field. The model is composed of three major steps: firstly decompose the input image into several feature maps representing different frequency bands that cover the whole frequency domain by utilizing Gabor wavelet. Secondly, whiten the feature maps to highlight the embedded saliency information. Thirdly, select some optimal maps, simulating the response of receptive field especially nCRF, to generate the saliency map. Experimental results show that the proposed algorithm is able to work with stable effect and outstanding performance in a variety of situations as human beings do and is adaptive to both psychological patterns and natural images. Beyond that, biological plausibility of nCRF and Gabor wavelet transform make this approach reliable. PMID:27275381

  7. Packet Switching Networks: An Introduction with Some Attention to Selected Vendors.

    ERIC Educational Resources Information Center

    Sanchez, James Joseph

    The purpose of this paper is to provide an overview of the history, development, and services of the packet switching network services that currently exist in the United States. The character of packet switching, a computerized method of transmitting data, is used as the basis for tracing the development of the industry itself. Contending that the…

  8. Negative Arousal Amplifies the Effects of Saliency in Short-Term Memory

    PubMed Central

    Sutherland, Matthew R.; Mather, Mara

    2013-01-01

    Evidence from two experiments suggests that negative arousal increases biases in attention that result from differences in visual salience. Participants were exposed to negative arousing or neutral sounds before briefly viewing an array of letters. They reported as many of the letters as they could, and attention was biased to certain letters by increasing salience through visual contrast. Regardless of the type of sound heard, participants were more likely to recall high-salience letters than low-salience letters. However, on arousing trials recall of high-salience letters increased, while recall of low-salience letters did not. These findings indicate that negative emotional arousal increases the selectivity of attention, and provides evidence for arousal-biased competition (ABC) theory (Mather & Sutherland, 2011), which predicts that emotional arousal enhances representations of stimuli that have priority. PMID:22642352

  9. The influence of motivational salience on saccade latencies.

    PubMed

    Rothkirch, Marcus; Ostendorf, Florian; Sax, Anne-Lene; Sterzer, Philipp

    2013-01-01

    Eye movements provide a direct link to study the allocation of overt attention to stimuli in the visual field. The initiation of saccades towards visual stimuli is known to be influenced by the bottom-up salience of stimuli as well as the motivational context of the task. Here, we asked whether the initiation of saccades is also influenced by the intrinsic motivational salience of a stimulus. Face stimuli were first associated with positive or negative motivational salience through instrumental learning. The same faces served as target stimuli in a subsequent saccade task, in which their motivational salience was no longer task-relevant. Participants performed either voluntary saccades, which required the selection of the saccade target out of two simultaneously presented stimuli (experiment 1), or reactive saccades, where only the target stimulus was presented (experiment 2). We found a specific effect of learned positive stimulus value on the latencies of voluntary saccades: For faces with high versus low positive motivational salience, saccadic latencies were significantly reduced. No such difference was observed for previously punished faces. In contrast, reactive saccades to both previously rewarded and punished faces were unaffected by learned stimulus value. Our findings show for the first time that saccadic preparation is susceptible to the acquired intrinsic motivational salience of visual stimuli. Based on the observation that only voluntary saccades but not reactive saccades were modulated, we conclude that the recruitment of neural processes for target identification is required to allow for an influence of motivational stimulus salience on saccadic preparation. PMID:23283417

  10. What do saliency models predict?

    PubMed Central

    Koehler, Kathryn; Guo, Fei; Zhang, Sheng; Eckstein, Miguel P.

    2014-01-01

    Saliency models have been frequently used to predict eye movements made during image viewing without a specified task (free viewing). Use of a single image set to systematically compare free viewing to other tasks has never been performed. We investigated the effect of task differences on the ability of three models of saliency to predict the performance of humans viewing a novel database of 800 natural images. We introduced a novel task where 100 observers made explicit perceptual judgments about the most salient image region. Other groups of observers performed a free viewing task, saliency search task, or cued object search task. Behavior on the popular free viewing task was not best predicted by standard saliency models. Instead, the models most accurately predicted the explicit saliency selections and eye movements made while performing saliency judgments. Observers' fixations varied similarly across images for the saliency and free viewing tasks, suggesting that these two tasks are related. The variability of observers' eye movements was modulated by the task (lowest for the object search task and greatest for the free viewing and saliency search tasks) as well as the clutter content of the images. Eye movement variability in saliency search and free viewing might be also limited by inherent variation of what observers consider salient. Our results contribute to understanding the tasks and behavioral measures for which saliency models are best suited as predictors of human behavior, the relationship across various perceptual tasks, and the factors contributing to observer variability in fixational eye movements. PMID:24618107

  11. Between-Person and Within-Person Associations among Processing Speed, Attention Switching and Working Memory in Younger and Older Adults

    PubMed Central

    Stawski, Robert S.; Sliwinski, Martin J.; Hofer, Scott M.

    2013-01-01

    Background/Study Context Theories of cognitive aging predict associations among processes that transpire within individuals, but are often tested by examining between-person relationships. The authors provide an empirical demonstration of how associations among measures of processing speed, attention switching, and working memory are different when considered between persons versus within persons over time. Methods A sample of 108 older adults (Mage: 80.8, range: 66–95) and 68 younger adults (Mage: 20.2, range:18–24) completed measures of processing speed, attention switching, and working memory on six occasions over a 14-day period. Multilevel modeling was used to examine processing speed and attention switching performance as predictors of working memory performance simultaneously across days (within-person) and across individuals (between-person). Results The findings indicates that simple comparison and response speed predicted working memory better than attention switching between persons, whereas attention switching predicted working memory better than simple comparison and response speed within persons over time. Furthermore, the authors did not observe strong evidence of age differences in these associations either within or between persons. Conclusion The findings of the current study suggest that processing speed is important for understanding between-person and age-related differences in working memory, whereas attention switching is more important for understanding within-person variation in working memory. The authors conclude that theories of cognitive aging should be evaluated by analysis of within-person processes, not exclusively age-related individual differences. PMID:23421639

  12. Attentional switching in intellectually gifted and average children: effects on performance and ERP.

    PubMed

    Duan, Xiaoju; Shi, Jiannong

    2014-04-01

    The study compared the performance and brain activity of children who were intellectually gifted or of average intelligence. 13 intellectually gifted (4 girls, 9 boys; M age = 12.0 yr., SD = 0.2) and 13 average children (5 girls, 8 boys; M age = 11.9 yr., SD = 0.3) participated in a task-switching experiment. The children performed a task repeatedly (single-trial blocks) or switched between two different tasks (mixed-trial blocks). Intellectually gifted children performed quicker than the average group for both mixed and single-trial blocks. The electroencephalography P300 amplitude was larger in the mixed compared to the single-trial condition, but this effect was observed only in the gifted children. The results support the notion that gifted children are characterized by a faster maturation that leads to an 'adult-like' brain activity. PMID:24897910

  13. Attentional Switching in Humans and Flies: Rivalry in Large and Miniature Brains

    PubMed Central

    Miller, Steven Mark; Ngo, Trung Thanh; van Swinderen, Bruno

    2012-01-01

    Human perception, and consequently behavior, is driven by attention dynamics. In the special case of rivalry, where attention alternates between competing percepts, such dynamics can be measured and their determinants investigated. A recent study in the fruit fly, Drosophila melanogaster, now shows that the origins of attentional rivalry may be quite ancient. Furthermore, individual variation exists in the rate of attentional rivalry in both humans and flies, and in humans this is under substantial genetic influence. In the pathophysiological realm, slowing of rivalry rate is associated with the heritable psychiatric condition, bipolar disorder. Fly rivalry may therefore prove a powerful model to examine genetic and molecular influences on rivalry rate, and may even shed light on human cognitive and behavioral dysfunction. PMID:22279432

  14. Fused methods for visual saliency estimation

    NASA Astrophysics Data System (ADS)

    Danko, Amanda S.; Lyu, Siwei

    2015-02-01

    In this work, we present a new model of visual saliency by combing results from existing methods, improving upon their performance and accuracy. By fusing pre-attentive and context-aware methods, we highlight the abilities of state-of-the-art models while compensating for their deficiencies. We put this theory to the test in a series of experiments, comparatively evaluating the visual saliency maps and employing them for content-based image retrieval and thumbnail generation. We find that on average our model yields definitive improvements upon recall and f-measure metrics with comparable precisions. In addition, we find that all image searches using our fused method return more correct images and additionally rank them higher than the searches using the original methods alone.

  15. Behavioral effects of transcranial pulsed current stimulation (tPCS): Speed-accuracy tradeoff in attention switching task.

    PubMed

    Morales-Quezada, Leon; Leite, Jorge; Carvalho, Sandra; Castillo-Saavedra, Laura; Cosmo, Camila; Fregni, Felipe

    2016-08-01

    Transcranial pulsed current stimulation (tPCS) has been shown to increase inter-hemispheric coherence of brain oscillatory activity, mainly in fronto-temporal regions, leading to enhancement of functional connectivity across neural networks. The question is whether tPCS can modulate behavior significantly. Our aim was to identify the effects of tPCS on paired associative learning task (PALT) and attention switching task (AST), and to further categorize physiological autonomic responses by heart rate variability and electrodermal activity measurements before and after task performance. Thirty healthy volunteers were randomized to receive a single session of sham or active 2mA tPCS stimulation with a random frequency between 1 and 5Hz. We show that active tPCS significantly improved response time in the AST compared to sham stimulation, so that subjects who received active tPCS significantly exhibit decreased switching cost between repeat and switch trials. No differences were found in response accuracy on AST and PALT. No significant changes were observed in physiological parameters. Based on our results, we suggest that tPCS has a more pronounced effect on tasks that require the increase of functional connectivity across pre-existent neural circuitry, rather than on tasks that require the development of new learning circuits or the creation of new connections. PMID:26851768

  16. Salience Is Only Briefly Represented: Evidence from Probe-Detection Performance

    ERIC Educational Resources Information Center

    Donk, Mieke; Soesman, Leroy

    2010-01-01

    Salient objects in the visual field tend to capture attention. The present study aimed to examine the time-course of salience effects using a probe-detection task. Eight experiments investigated how the salience of different orientation singletons affected probe reaction time as a function of stimulus onset asynchrony (SOA) between the…

  17. Switching in the Cocktail Party: Exploring Intentional Control of Auditory Selective Attention

    ERIC Educational Resources Information Center

    Koch, Iring; Lawo, Vera; Fels, Janina; Vorlander, Michael

    2011-01-01

    Using a novel variant of dichotic selective listening, we examined the control of auditory selective attention. In our task, subjects had to respond selectively to one of two simultaneously presented auditory stimuli (number words), always spoken by a female and a male speaker, by performing a numerical size categorization. The gender of the…

  18. Visually guided pointing movements are driven by the salience map.

    PubMed

    Zehetleitner, Michael; Hegenloh, Michael; Müller, Hermann J

    2011-01-01

    Visual salience maps are assumed to mediate target selection decisions in a motor-unspecific manner; accordingly, modulations of salience influence yes/no target detection or left/right localization responses in manual key-press search tasks, as well as ocular or skeletal movements to the target. Although widely accepted, this core assumption is based on little psychophysical evidence. At least four modulations of salience are known to influence the speed of visual search for feature singletons: (i) feature contrast, (ii) cross-trial dimension sequence and (iii) semantic pre-cueing of the target dimension, and (iv) dimensional target redundancy. If salience guides also manual pointing movements, their initiation latencies (and durations) should be affected by the same four manipulations of salience. Four experiments, each examining one of these manipulations, revealed this to be the case. Thus, these effects are seen independently of the motor response required to signal the perceptual decision (e.g., directed manual pointing as well as simple yes/no detection responses). This supports the notion of a motor-unspecific salience map, which guides covert attention as well as overt eye and hand movements. PMID:21282341

  19. The Social Perceptual Salience Effect

    ERIC Educational Resources Information Center

    Inderbitzin, Martin P.; Betella, Alberto; Lanata, Antonio; Scilingo, Enzo P.; Bernardet, Ulysses; Verschure, Paul F. M. J.

    2013-01-01

    Affective processes appraise the salience of external stimuli preparing the agent for action. So far, the relationship between stimuli, affect, and action has been mainly studied in highly controlled laboratory conditions. In order to find the generalization of this relationship to social interaction, we assess the influence of the salience of…

  20. Ecological Origins of Object Salience: Reward, Uncertainty, Aversiveness, and Novelty

    PubMed Central

    Ghazizadeh, Ali; Griggs, Whitney; Hikosaka, Okihide

    2016-01-01

    Among many objects around us, some are more salient than others (i.e., attract our attention automatically). Some objects may be inherently salient (e.g., brighter), while others may become salient by virtue of their ecological relevance through experience. However, the role of ecological experience in automatic attention has not been studied systematically. To address this question, we let subjects (macaque monkeys) view a large number of complex objects (>300), each experienced repeatedly (>5 days) with rewarding, aversive or no outcome association (mere-perceptual exposure). Test of salience was done on separate days using free viewing with no outcome. We found that gaze was biased among the objects from the outset, affecting saccades to objects or fixations within objects. When the outcome was rewarding, gaze preference was stronger (i.e., positive) for objects with larger or equal but uncertain rewards. The effects of aversive outcomes were variable. Gaze preference was positive for some outcome associations (e.g., airpuff), but negative for others (e.g., time-out), possibly due to differences in threat levels. Finally, novel objects attracted gaze, but mere perceptual exposure of objects reduced their salience (learned negative salience). Our results show that, in primates, object salience is strongly influenced by previous ecological experience and is supported by a large memory capacity. Owing to such high capacity for learned salience, the ability to rapidly choose important objects can grow during the entire life to promote biological fitness. PMID:27594825

  1. Ecological Origins of Object Salience: Reward, Uncertainty, Aversiveness, and Novelty.

    PubMed

    Ghazizadeh, Ali; Griggs, Whitney; Hikosaka, Okihide

    2016-01-01

    Among many objects around us, some are more salient than others (i.e., attract our attention automatically). Some objects may be inherently salient (e.g., brighter), while others may become salient by virtue of their ecological relevance through experience. However, the role of ecological experience in automatic attention has not been studied systematically. To address this question, we let subjects (macaque monkeys) view a large number of complex objects (>300), each experienced repeatedly (>5 days) with rewarding, aversive or no outcome association (mere-perceptual exposure). Test of salience was done on separate days using free viewing with no outcome. We found that gaze was biased among the objects from the outset, affecting saccades to objects or fixations within objects. When the outcome was rewarding, gaze preference was stronger (i.e., positive) for objects with larger or equal but uncertain rewards. The effects of aversive outcomes were variable. Gaze preference was positive for some outcome associations (e.g., airpuff), but negative for others (e.g., time-out), possibly due to differences in threat levels. Finally, novel objects attracted gaze, but mere perceptual exposure of objects reduced their salience (learned negative salience). Our results show that, in primates, object salience is strongly influenced by previous ecological experience and is supported by a large memory capacity. Owing to such high capacity for learned salience, the ability to rapidly choose important objects can grow during the entire life to promote biological fitness. PMID:27594825

  2. Saliency detection for stereoscopic images.

    PubMed

    Fang, Yuming; Wang, Junle; Narwaria, Manish; Le Callet, Patrick; Lin, Weisi

    2014-06-01

    Many saliency detection models for 2D images have been proposed for various multimedia processing applications during the past decades. Currently, the emerging applications of stereoscopic display require new saliency detection models for salient region extraction. Different from saliency detection for 2D images, the depth feature has to be taken into account in saliency detection for stereoscopic images. In this paper, we propose a novel stereoscopic saliency detection framework based on the feature contrast of color, luminance, texture, and depth. Four types of features, namely color, luminance, texture, and depth, are extracted from discrete cosine transform coefficients for feature contrast calculation. A Gaussian model of the spatial distance between image patches is adopted for consideration of local and global contrast calculation. Then, a new fusion method is designed to combine the feature maps to obtain the final saliency map for stereoscopic images. In addition, we adopt the center bias factor and human visual acuity, the important characteristics of the human visual system, to enhance the final saliency map for stereoscopic images. Experimental results on eye tracking databases show the superior performance of the proposed model over other existing methods. PMID:24832595

  3. Changes in infants' ability to switch visual attention in the first three months of life.

    PubMed

    Atkinson, J; Hood, B; Wattam-Bell, J; Braddick, O

    1992-01-01

    The abilities of 1-month-old and 3-month-old infants to shift their gaze from a central target to a peripheral target were compared in four experiments. In experiment 1 targets matched in mean luminance to the background were presented to infants in the periphery at varying levels of contrast. The contrast thresholds for target detection were found to be significantly different for 1-month-olds compared with 3-month-olds. With targets set close to these contrast thresholds, correct refixations and the latency for shifting attention were examined in experiment 2. Two conditions were used: a peripheral target was presented against a homogeneous background (noncompetition); and in the second condition, the patterned target appeared at one of two lighter peripheral windows set against a darker background (competition). Although there was no difference between the two age groups in the latency for shifting visual attention, 1-month-olds were found to make more directional errors in the competition condition. The competition effect of two potential targets on latencies was examined in experiment 3. In the competition condition, two identical peripheral patterned targets were presented to the infants. The 3-month-olds refixated more quickly to one of the double targets in the competition condition than to a single peripheral target, whereas 1-month-olds were slowed down by a double target display. Finally, in experiment 4 the ability of the infants to process and disengage from a central stimulus and to refixate towards a similar peripheral target was examined. This type of competition disrupted both the direction of the first eye movement and the latency to shift attention in both age groups. However, the effect was significantly greater for the 1-month-olds. Taken together, the results of these experiments demonstrate the greater disruption of fixation-shift behaviour in 1-month-olds compared with 3-month-olds when competing visual stimuli are used. This developmental

  4. The Application of Visual Saliency Models in Objective Image Quality Assessment: A Statistical Evaluation.

    PubMed

    Zhang, Wei; Borji, Ali; Wang, Zhou; Le Callet, Patrick; Liu, Hantao

    2016-06-01

    Advances in image quality assessment have shown the potential added value of including visual attention aspects in its objective assessment. Numerous models of visual saliency are implemented and integrated in different image quality metrics (IQMs), but the gain in reliability of the resulting IQMs varies to a large extent. The causes and the trends of this variation would be highly beneficial for further improvement of IQMs, but are not fully understood. In this paper, an exhaustive statistical evaluation is conducted to justify the added value of computational saliency in objective image quality assessment, using 20 state-of-the-art saliency models and 12 best-known IQMs. Quantitative results show that the difference in predicting human fixations between saliency models is sufficient to yield a significant difference in performance gain when adding these saliency models to IQMs. However, surprisingly, the extent to which an IQM can profit from adding a saliency model does not appear to have direct relevance to how well this saliency model can predict human fixations. Our statistical analysis provides useful guidance for applying saliency models in IQMs, in terms of the effect of saliency model dependence, IQM dependence, and image distortion dependence. The testbed and software are made publicly available to the research community. PMID:26277009

  5. Switching Attention Within Working Memory is Reflected in the P3a Component of the Human Event-Related Brain Potential

    PubMed Central

    Berti, Stefan

    2016-01-01

    The flexible access to information in working memory is crucial for adaptive behavior. It is assumed that this is realized by switching the focus of attention within working memory. Switching of attention is mirrored in the P3a component of the human event-related brain potential (ERP) and it has been argued that the processes reflected by the P3a are also relevant for selecting information within working memory. The aim of the present study was to further evaluate whether the P3a mirrors genuine switching of attention within working memory by applying an object switching task: Participants updated a memory list of four digits either by replacing one item with another digit or by processing the stored digit. ERPs were computed separately for two types of trials: (1) trials in which an object was repeated and (2) trials in which a switch to a new object was required in order to perform the task. Object-switch trials showed increased response times compared with repetition trials in both task conditions. In addition, switching costs were increased in the processing compared with the replacement condition. Pronounced P3a’s were obtained in switching trials but there were no difference between the two updating tasks (replacement or processing). These results were qualified by the finding that the magnitude of the visual location shift also affects the ERPs in the P3a time window. Taken together, the present pattern of results suggest that the P3a reflects an initial process of selecting information in working memory but not the memory updating itself. PMID:26779009

  6. Effects of salience are both short- and long-lived.

    PubMed

    Orquin, Jacob L; Lagerkvist, Carl Johan

    2015-09-01

    A salient object can attract attention irrespective of its relevance to current goals. However, this bottom up effect tends to be short-lived (e.g. <150 ms) and it is generally assumed that top down processes such as goals or task instructions operating in later time windows override the effect of salience operating in early time windows. While the majority of studies on visual search and scene viewing comply with the assumptions of top down and bottom up processes operating in different time windows and that the former overrides the latter, we point to some possible anomalies in decision research. To explore these anomalies and thereby test the two key assumptions, we manipulate the salience and valence of one information cue in a decision task. Our analyses reveal that in decision tasks top down and bottom up processes do not operate in different time windows as predicted, nor does the former process necessarily override the latter. Instead, we find that the maximum effect of salience on the likelihood of making a saccade to the target cue is delayed until about 20 saccades after stimulus onset and that the effects of salience and valence are additive rather than multiplicative. Further, we find that in the positive and neutral valence conditions, salience continues to exert pressure on saccadic latency, i.e. the interval between saccades to the target with high salience targets being fixated faster than low salience targets. Our findings challenge the assumption that top down and bottom up processes operate in different time windows and the assumption that top down processes necessarily override bottom up processes. PMID:26188691

  7. Measuring the amplification of attention.

    PubMed

    Blaser, E; Sperling, G; Lu, Z L

    1999-09-28

    An ambiguous motion paradigm, in which the direction of apparent motion is determined by salience (i.e., the extent to which an area is perceived as figure versus ground), is used to assay the amplification of color by attention to color. In the red-green colored gratings used in these experiments, without attention instructions, salience depends on the chromaticity difference between colored stripes embedded in the motion sequence and the yellow background. Selective attention to red (or to green) alters the perceived direction of motion and is found to be equivalent to increasing the physical redness (or greenness) by 25-117%, depending on the observer and color. Whereas attention to a color drastically alters the salience of that color, it leaves color appearance unchanged. A computational model, which embodies separate, parallel pathways for object perception and for salience, accounts for 99% of the variance of the experimental data. PMID:10500237

  8. Saliency prediction on stereoscopic videos.

    PubMed

    Kim, Haksub; Lee, Sanghoon; Bovik, Alan Conrad

    2014-04-01

    We describe a new 3D saliency prediction model that accounts for diverse low-level luminance, chrominance, motion, and depth attributes of 3D videos as well as high-level classifications of scenes by type. The model also accounts for perceptual factors, such as the nonuniform resolution of the human eye, stereoscopic limits imposed by Panum's fusional area, and the predicted degree of (dis) comfort felt, when viewing the 3D video. The high-level analysis involves classification of each 3D video scene by type with regard to estimated camera motion and the motions of objects in the videos. Decisions regarding the relative saliency of objects or regions are supported by data obtained through a series of eye-tracking experiments. The algorithm developed from the model elements operates by finding and segmenting salient 3D space-time regions in a video, then calculating the saliency strength of each segment using measured attributes of motion, disparity, texture, and the predicted degree of visual discomfort experienced. The saliency energy of both segmented objects and frames are weighted using models of human foveation and Panum's fusional area yielding a single predictor of 3D saliency. PMID:24565790

  9. Orientation saliency without visual cortex and target selection in archer fish

    PubMed Central

    Mokeichev, Alik; Segev, Ronen; Ben-Shahar, Ohad

    2010-01-01

    Our visual attention is attracted by salient stimuli in our environment and affected by primitive features such as orientation, color, and motion. Perceptual saliency due to orientation contrast has been extensively demonstrated in behavioral experiments with humans and other primates and is believed to be facilitated by the functional organization of the primary visual cortex. In behavioral experiments with the archer fish, a proficient hunter with remarkable visual abilities, we found an orientation saliency effect similar to that observed in human subjects. Given the enormous evolutionary distance between humans and archer fish, our findings suggest that orientation-based saliency constitutes a fundamental building block for efficient visual information processing. PMID:20837539

  10. The Social Salience Hypothesis of Oxytocin.

    PubMed

    Shamay-Tsoory, Simone G; Abu-Akel, Ahmad

    2016-02-01

    Oxytocin is a nonapeptide that also serves as a neuromodulator in the human central nervous system. Over the last decade, a sizeable body of literature has examined its effects on social behavior in humans. These studies show that oxytocin modulates various aspects of social behaviors such as empathy, trust, in-group preference, and memory of socially relevant cues. Several theoretical formulations have attempted to explain the effects of oxytocin. The prosocial account argues that oxytocin mainly enhances affiliative prosocial behaviors; the fear/stress theory suggests that oxytocin affects social performance by attenuating stress; and the in-/out-group approach proposes that oxytocin regulates cooperation and conflict among humans in the context of intergroup relations. Nonetheless, accumulating evidence reveals that the effects of oxytocin are dependent on a variety of contextual aspects and the individual's characteristics and can induce antisocial effects including aggression and envy. In an attempt to reconcile these accounts, we suggest a theoretical framework that focuses on the overarching role of oxytocin in regulating the salience of social cues through its interaction with the dopaminergic system. Crucially, the salience effect modulates attention orienting responses to external contextual social cues (e.g., competitive vs. cooperative environment) but is dependent on baseline individual differences such as gender, personality traits, and degree of psychopathology. This view could have important implications for the therapeutic applications of oxytocin in conditions characterized with aberrant social behavior. PMID:26321019

  11. Atypical Visual Saliency in Autism Spectrum Disorder Quantified through Model-Based Eye Tracking.

    PubMed

    Wang, Shuo; Jiang, Ming; Duchesne, Xavier Morin; Laugeson, Elizabeth A; Kennedy, Daniel P; Adolphs, Ralph; Zhao, Qi

    2015-11-01

    The social difficulties that are a hallmark of autism spectrum disorder (ASD) are thought to arise, at least in part, from atypical attention toward stimuli and their features. To investigate this hypothesis comprehensively, we characterized 700 complex natural scene images with a novel three-layered saliency model that incorporated pixel-level (e.g., contrast), object-level (e.g., shape), and semantic-level attributes (e.g., faces) on 5,551 annotated objects. Compared with matched controls, people with ASD had a stronger image center bias regardless of object distribution, reduced saliency for faces and for locations indicated by social gaze, and yet a general increase in pixel-level saliency at the expense of semantic-level saliency. These results were further corroborated by direct analysis of fixation characteristics and investigation of feature interactions. Our results for the first time quantify atypical visual attention in ASD across multiple levels and categories of objects. PMID:26593094

  12. Atypical visual saliency in autism spectrum disorder quantified through model-based eye tracking

    PubMed Central

    Wang, Shuo; Jiang, Ming; Duchesne, Xavier Morin; Laugeson, Elizabeth A.; Kennedy, Daniel P.; Adolphs, Ralph; Zhao, Qi

    2015-01-01

    Summary The social difficulties that are a hallmark of autism spectrum disorder (ASD) are thought to arise, at least in part, from atypical attention towards stimuli and their features. To investigate this hypothesis comprehensively, we characterized 700 complex natural scene images with a novel 3-layered saliency model that incorporated pixel-level (e.g., contrast), object-level (e.g., shape), and semantic-level attributes (e.g., faces) on 5551 annotated objects. Compared to matched controls, people with ASD had a stronger image center bias regardless of object distribution, reduced saliency for faces and for locations indicated by social gaze, yet a general increase in pixel-level saliency at the expense of semantic-level saliency. These results were further corroborated by direct analysis of fixation characteristics and investigation of feature interactions. Our results for the first time quantify atypical visual attention in ASD across multiple levels and categories of objects. PMID:26593094

  13. The relationship between language proficiency and attentional control in Cantonese-English bilingual children: evidence from Simon, Simon switching, and working memory tasks

    PubMed Central

    Tse, Chi-Shing; Altarriba, Jeanette

    2014-01-01

    By administering Simon, Simon switching, and operation-span working memory tasks to Cantonese-English bilingual children who varied in their first-language (L1, Cantonese) and second-language (L2, English) proficiencies, as quantified by standardized vocabulary test performance, the current study examined the effects of L1 and L2 proficiency on attentional control performance. Apart from mean performance, we conducted ex-Gaussian analyses to capture the modal and positive-tail components of participants' reaction time distributions in the Simon and Simon switching tasks. Bilinguals' L2 proficiency was associated with higher scores in the operation span task, and a shift of reaction time distributions in incongruent trials, relative to congruent trials (Simon effect in μ), and the tail size of reaction time distributions (τ) regardless of trial types in the Simon task. Bilinguals' L1 proficiency, which was strongly associated with participants' age, showed similar results, except that it was not associated with the Simon effect in μ. In contrast, neither bilinguals' L1 nor L2 proficiency modulated the global switch cost or local switch cost in the Simon switching task. After taking into account potential cognitive maturation by partialling out the participants' age, only (a) scores in the working memory task and (b) RT in incongruent trials and (c) Simon effect in μ in the Simon task could still be predicted by bilinguals' L2 proficiency. Overall, the current findings suggest that bilingual children's L2 proficiency was associated with their conflict resolution and working memory capacity, but not goal maintenance or task-set switching, when they performed the cognitive tasks that demanded attentional control. This was not entirely consistent with the findings of college-age bilinguals reported in previous studies. PMID:25232345

  14. Hypergraph-based saliency map generation with potential region-of-interest approximation and validation

    NASA Astrophysics Data System (ADS)

    Liang, Zhen; Fu, Hong; Chi, Zheru; Feng, Dagan

    2012-01-01

    A novel saliency model is proposed in this paper to automatically process images in the similar way as the human visual system which focuses on conspicuous regions that catch human beings' attention. The model combines a hypergraph representation and a partitioning process with potential region-of-interest (p-ROI) approximation and validation. Experimental results demonstrate that the proposed method shows considerable improvement in the performance of saliency map generation.

  15. Neural networks supporting switching, hypothesis testing, and rule application.

    PubMed

    Liu, Zhiya; Braunlich, Kurt; Wehe, Hillary S; Seger, Carol A

    2015-10-01

    We identified dynamic changes in recruitment of neural connectivity networks across three phases of a flexible rule learning and set-shifting task similar to the Wisconsin Card Sort Task: switching, rule learning via hypothesis testing, and rule application. During fMRI scanning, subjects viewed pairs of stimuli that differed across four dimensions (letter, color, size, screen location), chose one stimulus, and received feedback. Subjects were informed that the correct choice was determined by a simple unidimensional rule, for example "choose the blue letter". Once each rule had been learned and correctly applied for 4-7 trials, subjects were cued via either negative feedback or visual cues to switch to learning a new rule. Task performance was divided into three phases: Switching (first trial after receiving the switch cue), hypothesis testing (subsequent trials through the last error trial), and rule application (correct responding after the rule was learned). We used both univariate analysis to characterize activity occurring within specific regions of the brain, and a multivariate method, constrained principal component analysis for fMRI (fMRI-CPCA), to investigate how distributed regions coordinate to subserve different processes. As hypothesized, switching was subserved by a limbic network including the ventral striatum, thalamus, and parahippocampal gyrus, in conjunction with cortical salience network regions including the anterior cingulate and frontoinsular cortex. Activity in the ventral striatum was associated with switching regardless of how switching was cued; visually cued shifts were associated with additional visual cortical activity. After switching, as subjects moved into the hypothesis testing phase, a broad fronto-parietal-striatal network (associated with the cognitive control, dorsal attention, and salience networks) increased in activity. This network was sensitive to rule learning speed, with greater extended activity for the slowest

  16. Hierarchical Image Saliency Detection on Extended CSSD.

    PubMed

    Shi, Jianping; Yan, Qiong; Xu, Li; Jia, Jiaya

    2016-04-01

    Complex structures commonly exist in natural images. When an image contains small-scale high-contrast patterns either in the background or foreground, saliency detection could be adversely affected, resulting erroneous and non-uniform saliency assignment. The issue forms a fundamental challenge for prior methods. We tackle it from a scale point of view and propose a multi-layer approach to analyze saliency cues. Different from varying patch sizes or downsizing images, we measure region-based scales. The final saliency values are inferred optimally combining all the saliency cues in different scales using hierarchical inference. Through our inference model, single-scale information is selected to obtain a saliency map. Our method improves detection quality on many images that cannot be handled well traditionally. We also construct an extended Complex Scene Saliency Dataset (ECSSD) to include complex but general natural images. PMID:26959676

  17. Learning to predict where human gaze is using quaternion DCT based regional saliency detection

    NASA Astrophysics Data System (ADS)

    Li, Ting; Xu, Yi; Zhang, Chongyang

    2014-09-01

    Many current visual attention approaches used semantic features to accurately capture human gaze. However, these approaches demand high computational cost and can hardly be applied to daily use. Recently, some quaternion-based saliency detection models, such as PQFT (phase spectrum of Quaternion Fourier Transform), QDCT (Quaternion Discrete Cosine Transform), have been proposed to meet real-time requirement of human gaze tracking tasks. However, current saliency detection methods used global PQFT and QDCT to locate jump edges of the input, which can hardly detect the object boundaries accurately. To address the problem, we improved QDCT-based saliency detection model by introducing superpixel-wised regional saliency detection mechanism. The local smoothness of saliency value distribution is emphasized to distinguish noises of background from salient regions. Our algorithm called saliency confidence can distinguish the patches belonging to the salient object and those of the background. It decides whether the image patches belong to the same region. When an image patch belongs to a region consisting of other salient patches, this patch should be salient as well. Therefore, we use saliency confidence map to get background weight and foreground weight to do the optimization on saliency map obtained by QDCT. The optimization is accomplished by least square method. The optimization approach we proposed unifies local and global saliency by combination of QDCT and measuring the similarity between each image superpixel. We evaluate our model on four commonly-used datasets (Toronto, MIT, OSIE and ASD) using standard precision-recall curves (PR curves), the mean absolute error (MAE) and area under curve (AUC) measures. In comparison with most state-of-art models, our approach can achieve higher consistency with human perception without training. It can get accurate human gaze even in cluttered background. Furthermore, it achieves better compromise between speed and accuracy.

  18. Mortality salience and morality: thinking about death makes people less utilitarian.

    PubMed

    Trémolière, Bastien; Neys, Wim De; Bonnefon, Jean-François

    2012-09-01

    According to the dual-process model of moral judgment, utilitarian responses to moral conflict draw on limited cognitive resources. Terror Management Theory, in parallel, postulates that mortality salience mobilizes these resources to suppress thoughts of death out of focal attention. Consequently, we predicted that individuals under mortality salience would be less likely to give utilitarian responses to moral conflicts. Two experiments corroborated this hypothesis. Experiment 1 showed that utilitarian responses to non-lethal harm conflicts were less frequent when participants were reminded of their mortality. Experiment 2 showed that the detrimental effect of mortality salience on utilitarian conflict judgments was comparable to that of an extreme concurrent cognitive load. These findings raise the question of whether private judgment and public debate about controversial moral issues might be shaped by mortality salience effects, since these issues (e.g., assisted suicide) often involve matters of life and death. PMID:22698994

  19. Development of salience-driven and visually-guided eye movement responses.

    PubMed

    Kooiker, Marlou J G; van der Steen, Johannes; Pel, Johan J M

    2016-03-01

    Development of visuospatial attention can be quantified from infancy onward using visually-guided eye movement responses. We investigated the interaction between eye movement response times and salience in target areas of visual stimuli over age in a cohort of typically developing children. A preferential looking (PL) paradigm consisting of stimuli with six different visual modalities (cartoons, contrast, form, local motion, color, global motion) was combined with the automated measurement of reflexive eye movements. Effective salience was defined as visual salience of each target area relative to its background. Three classes of PL stimuli were used: with high- (cartoon, contrast), intermediate- (local motion, form), and low-effective salience (global motion, color). Eye movement response times to the target areas of the six PL stimuli were nonverbally assessed in 220 children aged 1-12 years. The development of response times with age was influenced by effective salience: Response times to targets with high salience reached stable values earlier in development (around 4 years of age) than to targets with low salience (around 9 years of age). Intra-individual response time variability was highest for low-salient stimuli, and stabilized later (around 4 years) than for highly salient stimuli (2 years). The improvement of eye movement response times to visual modalities in PL stimuli occurred earlier in development for highly salient than for low-salient targets. The present age-dependent and salience-related results provide a quantitative and theoretical framework to assess the development of visuospatial attention, and of related visual processing capacities, in children from 1 year of age. PMID:26998802

  20. Perceptual salience affects the contents of working memory during free-recollection of objects from natural scenes.

    PubMed

    Pedale, Tiziana; Santangelo, Valerio

    2015-01-01

    One of the most important issues in the study of cognition is to understand which are the factors determining internal representation of the external world. Previous literature has started to highlight the impact of low-level sensory features (indexed by saliency-maps) in driving attention selection, hence increasing the probability for objects presented in complex and natural scenes to be successfully encoded into working memory (WM) and then correctly remembered. Here we asked whether the probability of retrieving high-saliency objects modulates the overall contents of WM, by decreasing the probability of retrieving other, lower-saliency objects. We presented pictures of natural scenes for 4 s. After a retention period of 8 s, we asked participants to verbally report as many objects/details as possible of the previous scenes. We then computed how many times the objects located at either the peak of maximal or minimal saliency in the scene (as indexed by a saliency-map; Itti et al., 1998) were recollected by participants. Results showed that maximal-saliency objects were recollected more often and earlier in the stream of successfully reported items than minimal-saliency objects. This indicates that bottom-up sensory salience increases the recollection probability and facilitates the access to memory representation at retrieval, respectively. Moreover, recollection of the maximal- (but not the minimal-) saliency objects predicted the overall amount of successfully recollected objects: The higher the probability of having successfully reported the most-salient object in the scene, the lower the amount of recollected objects. These findings highlight that bottom-up sensory saliency modulates the current contents of WM during recollection of objects from natural scenes, most likely by reducing available resources to encode and then retrieve other (lower saliency) objects. PMID:25741266

  1. Perceptual salience affects the contents of working memory during free-recollection of objects from natural scenes

    PubMed Central

    Pedale, Tiziana; Santangelo, Valerio

    2015-01-01

    One of the most important issues in the study of cognition is to understand which are the factors determining internal representation of the external world. Previous literature has started to highlight the impact of low-level sensory features (indexed by saliency-maps) in driving attention selection, hence increasing the probability for objects presented in complex and natural scenes to be successfully encoded into working memory (WM) and then correctly remembered. Here we asked whether the probability of retrieving high-saliency objects modulates the overall contents of WM, by decreasing the probability of retrieving other, lower-saliency objects. We presented pictures of natural scenes for 4 s. After a retention period of 8 s, we asked participants to verbally report as many objects/details as possible of the previous scenes. We then computed how many times the objects located at either the peak of maximal or minimal saliency in the scene (as indexed by a saliency-map; Itti et al., 1998) were recollected by participants. Results showed that maximal-saliency objects were recollected more often and earlier in the stream of successfully reported items than minimal-saliency objects. This indicates that bottom-up sensory salience increases the recollection probability and facilitates the access to memory representation at retrieval, respectively. Moreover, recollection of the maximal- (but not the minimal-) saliency objects predicted the overall amount of successfully recollected objects: The higher the probability of having successfully reported the most-salient object in the scene, the lower the amount of recollected objects. These findings highlight that bottom-up sensory saliency modulates the current contents of WM during recollection of objects from natural scenes, most likely by reducing available resources to encode and then retrieve other (lower saliency) objects. PMID:25741266

  2. Spatiochromatic Context Modeling for Color Saliency Analysis.

    PubMed

    Zhang, Jun; Wang, Meng; Zhang, Shengping; Li, Xuelong; Wu, Xindong

    2016-06-01

    Visual saliency is one of the most noteworthy perceptual abilities of human vision. Recent progress in cognitive psychology suggests that: 1) visual saliency analysis is mainly completed by the bottom-up mechanism consisting of feedforward low-level processing in primary visual cortex (area V1) and 2) color interacts with spatial cues and is influenced by the neighborhood context, and thus it plays an important role in a visual saliency analysis. From a computational perspective, the most existing saliency modeling approaches exploit multiple independent visual cues, irrespective of their interactions (or are not computed explicitly), and ignore contextual influences induced by neighboring colors. In addition, the use of color is often underestimated in the visual saliency analysis. In this paper, we propose a simple yet effective color saliency model that considers color as the only visual cue and mimics the color processing in V1. Our approach uses region-/boundary-defined color features with spatiochromatic filtering by considering local color-orientation interactions, therefore captures homogeneous color elements, subtle textures within the object and the overall salient object from the color image. To account for color contextual influences, we present a divisive normalization method for chromatic stimuli through the pooling of contrary/complementary color units. We further define a color perceptual metric over the entire scene to produce saliency maps for color regions and color boundaries individually. These maps are finally globally integrated into a one single saliency map. The final saliency map is produced by Gaussian blurring for robustness. We evaluate the proposed method on both synthetic stimuli and several benchmark saliency data sets from the visual saliency analysis to salient object detection. The experimental results demonstrate that the use of color as a unique visual cue achieves competitive results on par with or better than 12 state

  3. A model of proto-object based saliency

    PubMed Central

    Russell, Alexander F.; Mihalaş, Stefan; von der Heydt, Rudiger; Niebur, Ernst; Etienne-Cummings, Ralph

    2013-01-01

    Organisms use the process of selective attention to optimally allocate their computational resources to the instantaneously most relevant subsets of a visual scene, ensuring that they can parse the scene in real time. Many models of bottom-up attentional selection assume that elementary image features, like intensity, color and orientation, attract attention. Gestalt psychologists, how-ever, argue that humans perceive whole objects before they analyze individual features. This is supported by recent psychophysical studies that show that objects predict eye-fixations better than features. In this report we present a neurally inspired algorithm of object based, bottom-up attention. The model rivals the performance of state of the art non-biologically plausible feature based algorithms (and outperforms biologically plausible feature based algorithms) in its ability to predict perceptual saliency (eye fixations and subjective interest points) in natural scenes. The model achieves this by computing saliency as a function of proto-objects that establish the perceptual organization of the scene. All computational mechanisms of the algorithm have direct neural correlates, and our results provide evidence for the interface theory of attention. PMID:24184601

  4. Graduate Women's Career Salience, Aspirations, and Involvement.

    ERIC Educational Resources Information Center

    Lentz, Linda P.

    The career salience and career involvement of young women 1 year after graduation were assessed. Respondents attended nine coeducational colleges and six women's colleges located in the U.S. northeast. It was found that graduates of very selective women's colleges had a higher career salience rating on the Life Style Index than did their…

  5. Fusion of multi-sensory saliency maps for automated perception and control

    NASA Astrophysics Data System (ADS)

    Huber, David J.; Khosla, Deepak; Dow, Paul A.

    2009-05-01

    In many real-world situations and applications that involve humans or machines (e.g., situation awareness, scene understanding, driver distraction, workload reduction, assembly, robotics, etc.) multiple sensory modalities (e.g., vision, auditory, touch, etc.) are used. The incoming sensory information can overwhelm processing capabilities of both humans and machines. An approach for estimating what is most important in our sensory environment (bottom-up or goal-driven) and using that as a basis for workload reduction or taking an action could be of great benefit in applications involving humans, machines or human-machine interactions. In this paper, we describe a novel approach for determining high saliency stimuli in multi-modal sensory environments, e.g., vision, sound, touch, etc. In such environments, the high saliency stimuli could be a visual object, a sound source, a touch event, etc. The high saliency stimuli are important and should be attended to from perception, cognition or/and action perspective. The system accomplishes this by the fusion of saliency maps from multiple sensory modalities (e.g., visual and auditory) into a single, fused multimodal saliency map that is represented in a common, higher-level coordinate system. This paper describes the computational model and method for generating multi-modal or fused saliency map. The fused saliency map can be used to determine primary and secondary foci of attention as well as for active control of a hardware/device. Such a computational model of fused saliency map would be immensely useful for a machine-based or robot-based application in a multi-sensory environment. We describe the approach, system and present preliminary results on a real-robotic platform.

  6. Regional principal color based saliency detection.

    PubMed

    Lou, Jing; Ren, Mingwu; Wang, Huan

    2014-01-01

    Saliency detection is widely used in many visual applications like image segmentation, object recognition and classification. In this paper, we will introduce a new method to detect salient objects in natural images. The approach is based on a regional principal color contrast modal, which incorporates low-level and medium-level visual cues. The method allows a simple computation of color features and two categories of spatial relationships to a saliency map, achieving higher F-measure rates. At the same time, we present an interpolation approach to evaluate resulting curves, and analyze parameters selection. Our method enables the effective computation of arbitrary resolution images. Experimental results on a saliency database show that our approach produces high quality saliency maps and performs favorably against ten saliency detection algorithms. PMID:25379960

  7. Human-Centered Saliency Detection.

    PubMed

    Liu, Zhenbao; Wang, Xiao; Bu, Shuhui

    2016-06-01

    We introduce a new concept for detecting the saliency of 3-D shapes, that is, human-centered saliency (HCS) detection on the surface of shapes, whereby a given shape is analyzed not based on geometric or topological features directly obtained from the shape itself, but by studying how a human uses the object. Using virtual agents to simulate the ways in which humans interact with objects helps to understand shapes and detect their salient parts in relation to their functions. HCS detection is less affected by inconsistencies between the geometry or topology of the analyzed 3-D shapes. The potential benefit of the proposed method is that it is adaptable to variable shapes with the same semantics, as well as being robust against a geometrical and topological noise. Given a 3-D shape, its salient part is detected by automatically selecting a corresponding agent and making them interact with each other. Their adaption and alignment depend on an optimization framework and a training process. We demonstrate the detected salient parts for different types of objects together with the stability thereof. The salient parts can be used for important vision tasks, such as 3-D shape retrieval. PMID:26571539

  8. Emotional salience, emotional awareness, peculiar beliefs, and magical thinking.

    PubMed

    Berenbaum, Howard; Boden, M Tyler; Baker, John P

    2009-04-01

    Two studies with college student participants (Ns = 271 and 185) tested whether peculiar beliefs and magical thinking were associated with (a) the emotional salience of the stimuli about which individuals may have peculiar beliefs or magical thinking, (b) attention to emotion, and (c) clarity of emotion. Study 1 examined belief that a baseball team was cursed. Study 2 measured magical thinking using a procedure developed by P. Rozin and C. Nemeroff (2002). In both studies, peculiar beliefs and magical thinking were associated with Salience x Attention x Clarity interactions. Among individuals for whom the objects of the belief-magical thinking were highly emotionally salient and who had high levels of attention to emotion, higher levels of emotional clarity were associated with increased peculiar beliefs-magical thinking. In contrast, among individuals for whom the objects of the belief-magical thinking were not emotionally salient and who had high levels of attention to emotion, higher levels of emotional clarity were associated with diminished peculiar beliefs-magical thinking. PMID:19348532

  9. Response Switching Process in Children with Attention-Deficit-Hyperactivity Disorder on the Novel Continuous Performance Test

    ERIC Educational Resources Information Center

    Inoue, Yuki; Inagaki, Masumi; Gunji, Atsuko; Furushima, Wakana; Kaga, Makiko

    2008-01-01

    We examined the effects of previous trials on subsequent trials on performance in the continuous performance test (CPT) in children with attention-deficit-hyperactivity disorder (ADHD). Thirty-five non-medicated children with ADHD (31 males, four females; mean age 9y 10mo [SD 2y 4mo]) and 33 comparison children (20 males, 13 females; mean age 10y…

  10. Salience Assignment for Multiple-Instance Regression

    NASA Technical Reports Server (NTRS)

    Wagstaff, Kiri L.; Lane, Terran

    2007-01-01

    We present a Multiple-Instance Learning (MIL) algorithm for determining the salience of each item in each bag with respect to the bag's real-valued label. We use an alternating-projections constrained optimization approach to simultaneously learn a regression model and estimate all salience values. We evaluate this algorithm on a significant real-world problem, crop yield modeling, and demonstrate that it provides more extensive, intuitive, and stable salience models than Primary-Instance Regression, which selects a single relevant item from each bag.

  11. Mortality Salience and Morality: Thinking about Death Makes People Less Utilitarian

    ERIC Educational Resources Information Center

    Tremoliere, Bastien; De Neys, Wim; Bonnefon, Jean-Francois

    2012-01-01

    According to the dual-process model of moral judgment, utilitarian responses to moral conflict draw on limited cognitive resources. Terror Management Theory, in parallel, postulates that mortality salience mobilizes these resources to suppress thoughts of death out of focal attention. Consequently, we predicted that individuals under mortality…

  12. Ignoring real faces: effects of valence, threat, and salience.

    PubMed

    Blagrove, Elisabeth; Watson, Derrick G

    2014-04-01

    Facial stimuli have been shown to accrue a special status within visual processing, particularly when attention is prioritized to one face over another on the basis of affective content. This has been examined in relation to the ability of faces to guide or hold attention, or to resist attentional suppression. Previous work has shown that schematic faces can only be partially ignored and that the emotional valence of to-be-ignored faces has little effect. Given recent debates concerning the use of schematic faces, here we examined the ease with which photorealistic faces could be ignored. Although we found evidence of a partial preview benefit for these stimuli, the findings were complex, with stimulus salience, valence, and threat content interacting to affect both the strength of the benefit and target detection efficiency (Exps. 1-3). Experiment 4 then clarified the effects of physical salience and perceived stimulus similarity in the previous experiments, demonstrating that a combination of these factors is likely to account for the search patterns observed. PMID:24435898

  13. Saliency-based artificial object detection for satellite images

    NASA Astrophysics Data System (ADS)

    Ke, Shidong; Ding, Xiaoying; Yang, Daiqin; Chen, Zhenzhong; Fang, Yuming

    2015-03-01

    In this paper, we introduce a computational model of top-down saliency based on multiscale orientation information for artificial object detection for satellite images. Further more, the top-down saliency is integrated with bottom-up saliency to obtain the saliency map in satellite images. We compare our method to several state-of-the-art saliency detection models and demonstrate the superior performance in artificial object detection for satellite images.

  14. A Novel GBM Saliency Detection Model Using Multi-Channel MRI

    PubMed Central

    Banerjee, Subhashis; Mitra, Sushmita; Shankar, B. Uma; Hayashi, Yoichi

    2016-01-01

    The automatic computerized detection of regions of interest (ROI) is an important step in the process of medical image processing and analysis. The reasons are many, and include an increasing amount of available medical imaging data, existence of inter-observer and inter-scanner variability, and to improve the accuracy in automatic detection in order to assist doctors in diagnosing faster and on time. A novel algorithm, based on visual saliency, is developed here for the identification of tumor regions from MR images of the brain. The GBM saliency detection model is designed by taking cue from the concept of visual saliency in natural scenes. A visually salient region is typically rare in an image, and contains highly discriminating information, with attention getting immediately focused upon it. Although color is typically considered as the most important feature in a bottom-up saliency detection model, we circumvent this issue in the inherently gray scale MR framework. We develop a novel pseudo-coloring scheme, based on the three MRI sequences, viz. FLAIR, T2 and T1C (contrast enhanced with Gadolinium). A bottom-up strategy, based on a new pseudo-color distance and spatial distance between image patches, is defined for highlighting the salient regions in the image. This multi-channel representation of the image and saliency detection model help in automatically and quickly isolating the tumor region, for subsequent delineation, as is necessary in medical diagnosis. The effectiveness of the proposed model is evaluated on MRI of 80 subjects from the BRATS database in terms of the saliency map values. Using ground truth of the tumor regions for both high- and low- grade gliomas, the results are compared with four highly referred saliency detection models from literature. In all cases the AUC scores from the ROC analysis are found to be more than 0.999 ± 0.001 over different tumor grades, sizes and positions. PMID:26752735

  15. Emergence of Visual Saliency from Natural Scenes via Context-Mediated Probability Distributions Coding

    PubMed Central

    Xu, Jinhua; Yang, Zhiyong; Tsien, Joe Z.

    2010-01-01

    Visual saliency is the perceptual quality that makes some items in visual scenes stand out from their immediate contexts. Visual saliency plays important roles in natural vision in that saliency can direct eye movements, deploy attention, and facilitate tasks like object detection and scene understanding. A central unsolved issue is: What features should be encoded in the early visual cortex for detecting salient features in natural scenes? To explore this important issue, we propose a hypothesis that visual saliency is based on efficient encoding of the probability distributions (PDs) of visual variables in specific contexts in natural scenes, referred to as context-mediated PDs in natural scenes. In this concept, computational units in the model of the early visual system do not act as feature detectors but rather as estimators of the context-mediated PDs of a full range of visual variables in natural scenes, which directly give rise to a measure of visual saliency of any input stimulus. To test this hypothesis, we developed a model of the context-mediated PDs in natural scenes using a modified algorithm for independent component analysis (ICA) and derived a measure of visual saliency based on these PDs estimated from a set of natural scenes. We demonstrated that visual saliency based on the context-mediated PDs in natural scenes effectively predicts human gaze in free-viewing of both static and dynamic natural scenes. This study suggests that the computation based on the context-mediated PDs of visual variables in natural scenes may underlie the neural mechanism in the early visual cortex for detecting salient features in natural scenes. PMID:21209963

  16. Neural activities in V1 create the bottom-up saliency map of natural scenes.

    PubMed

    Chen, Cheng; Zhang, Xilin; Wang, Yizhou; Zhou, Tiangang; Fang, Fang

    2016-06-01

    A saliency map is the bottom-up contribution to the deployment of exogenous attention. It, as well as its underlying neural mechanism, is hard to identify because of the influence of top-down signals. A recent study showed that neural activities in V1 could create a bottom-up saliency map (Zhang et al. in Neuron 73(1):183-192, 2012). In this paper, we tested whether their conclusion can generalize to complex natural scenes. In order to avoid top-down influences, each image was presented with a low contrast for only 50 ms and was followed by a high contrast mask, which rendered the whole image invisible to participants (confirmed by a forced-choice test). The Posner cueing paradigm was adopted to measure the spatial cueing effect (i.e., saliency) by an orientation discrimination task. A positive cueing effect was found, and the magnitude of the cueing effect was consistent with the saliency prediction of a computational saliency model. In a following fMRI experiment, we used the same masked natural scenes as stimuli and measured BOLD signals responding to the predicted salient region (relative to the background). We found that the BOLD signal in V1, but not in other cortical areas, could well predict the cueing effect. These results suggest that the bottom-up saliency map of natural scenes could be created in V1, providing further evidence for the V1 saliency theory (Li in Trends Cogn Sci 6(1):9-16, 2002). PMID:26879771

  17. Saliency Mapping Enhanced by Structure Tensor

    PubMed Central

    He, Zhiyong; Chen, Xin; Sun, Lining

    2015-01-01

    We propose a novel efficient algorithm for computing visual saliency, which is based on the computation architecture of Itti model. As one of well-known bottom-up visual saliency models, Itti method evaluates three low-level features, color, intensity, and orientation, and then generates multiscale activation maps. Finally, a saliency map is aggregated with multiscale fusion. In our method, the orientation feature is replaced by edge and corner features extracted by a linear structure tensor. Following it, these features are used to generate contour activation map, and then all activation maps are directly combined into a saliency map. Compared to Itti method, our method is more computationally efficient because structure tensor is more computationally efficient than Gabor filter that is used to compute the orientation feature and our aggregation is a direct method instead of the multiscale operator. Experiments on Bruce's dataset show that our method is a strong contender for the state of the art. PMID:26788050

  18. Learned saliency transformations for gaze guidance

    NASA Astrophysics Data System (ADS)

    Vig, Eleonora; Dorr, Michael; Barth, Erhardt

    2011-03-01

    The saliency of an image or video region indicates how likely it is that the viewer of the image or video fixates that region due to its conspicuity. An intriguing question is how we can change the video region to make it more or less salient. Here, we address this problem by using a machine learning framework to learn from a large set of eye movements collected on real-world dynamic scenes how to alter the saliency level of the video locally. We derive saliency transformation rules by performing spatio-temporal contrast manipulations (on a spatio-temporal Laplacian pyramid) on the particular video region. Our goal is to improve visual communication by designing gaze-contingent interactive displays that change, in real time, the saliency distribution of the scene.

  19. Switching from neurostimulant therapy to atomoxetine in children and adolescents with attention-deficit hyperactivity disorder : clinical approaches and review of current available evidence.

    PubMed

    Prasad, Suyash; Steer, Chris

    2008-01-01

    This review provides practical information on and clinical reasons for switching children and young people with attention-deficit hyperactivity disorder (ADHD) from neurostimulants to atomoxetine, detailing currently available evidence, and switching options. The issue is of particular relevance following recent guidance from the National Institute for Health and Clinical Excellence and European ADHD guidelines endorsing the use of atomoxetine, along with the stimulants methylphenidate and dexamphetamine, in the management of ADHD in children and adolescents in the UK. The selective norepinephrine (noradrenaline) reuptake inhibitor, atomoxetine, is a non-stimulant drug licensed for the treatment of ADHD in children and adolescents, and in adults who have shown a response in childhood. Following the once-daily morning dose, its therapeutic effects extend through the waking hours, into late evening, and in some patients, through to early the next morning. Atomoxetine may be considered for patients who are unresponsive or incompletely responsive to stimulant treatment, have co-morbid conditions (e.g. tics, anxiety, depression), and have sleep disturbances or eating problems, for patients in whom stimulants are poorly tolerated, and for situations where there is potential for drug abuse or diversion. Atomoxetine has been shown to be effective in relapse prevention and there is suggestion that atomoxetine may have a positive effect on global functioning; specifically health-related quality of life, self-esteem, and social and family functioning. According to one study, approximately 50% of non-responders to methylphenidate will respond to atomoxetine therapy and approximately 75% of responders to methylphenidate will also respond to atomoxetine. Atomoxetine may be initiated by a schedule of dose increases and cross-tapering with methylphenidate. A slow titration schedule with divided doses minimizes the impact of adverse events within the first several weeks of

  20. What stands out in a scene? A study of human explicit saliency judgment.

    PubMed

    Borji, Ali; Sihite, Dicky N; Itti, Laurent

    2013-10-18

    Eye tracking has become the de facto standard measure of visual attention in tasks that range from free viewing to complex daily activities. In particular, saliency models are often evaluated by their ability to predict human gaze patterns. However, fixations are not only influenced by bottom-up saliency (computed by the models), but also by many top-down factors. Thus, comparing bottom-up saliency maps to eye fixations is challenging and has required that one tries to minimize top-down influences, for example by focusing on early fixations on a stimulus. Here we propose two complementary procedures to evaluate visual saliency. We seek whether humans have explicit and conscious access to the saliency computations believed to contribute to guiding attention and eye movements. In the first experiment, 70 observers were asked to choose which object stands out the most based on its low-level features in 100 images each containing only two objects. Using several state-of-the-art bottom-up visual saliency models that measure local and global spatial image outliers, we show that maximum saliency inside the selected object is significantly higher than inside the non-selected object and the background. Thus spatial outliers are a predictor of human judgments. Performance of this predictor is boosted by including object size as an additional feature. In the second experiment, observers were asked to draw a polygon circumscribing the most salient object in cluttered scenes. For each of 120 images, we show that a map built from annotations of 70 observers explains eye fixations of another 20 observers freely viewing the images, significantly above chance (dataset by Bruce and Tsotsos (2009); shuffled AUC score 0.62±0.07, chance 0.50, t-test p<0.05). We conclude that fixations agree with saliency judgments, and classic bottom-up saliency models explain both. We further find that computational models specifically designed for fixation prediction slightly outperform models

  1. When death is not a problem: Regulating implicit negative affect under mortality salience.

    PubMed

    Lüdecke, Christina; Baumann, Nicola

    2015-12-01

    Terror management theory assumes that death arouses existential anxiety in humans which is suppressed in focal attention. Whereas most studies provide indirect evidence for negative affect under mortality salience by showing cultural worldview defenses and self-esteem strivings, there is only little direct evidence for implicit negative affect under mortality salience. In the present study, we assume that this implicit affective reaction towards death depends on people's ability to self-regulate negative affect as assessed by the personality dimension of action versus state orientation. Consistent with our expectations, action-oriented participants judged artificial words to express less negative affect under mortality salience compared to control conditions whereas state-oriented participants showed the reversed pattern. PMID:26335149

  2. A proto-object based saliency model in three-dimensional space.

    PubMed

    Hu, Brian; Kane-Jackson, Ralinkae; Niebur, Ernst

    2016-02-01

    Most models of visual saliency operate on two-dimensional images, using elementary image features such as intensity, color, or orientation. The human visual system, however, needs to function in complex three-dimensional environments, where depth information is often available and may be used to guide the bottom-up attentional selection process. In this report we extend a model of proto-object based saliency to include depth information and evaluate its performance on three separate three-dimensional eye tracking datasets. Our results show that the additional depth information provides a small, but statistically significant, improvement in the model's ability to predict perceptual saliency (eye fixations) in natural scenes. The computational mechanisms of our model have direct neural correlates, and our results provide further evidence that proto-objects help to establish perceptual organization of the scene. PMID:26739278

  3. A Locally Weighted Fixation Density-Based Metric for Assessing the Quality of Visual Saliency Predictions.

    PubMed

    Gide, Milind S; Karam, Lina J

    2016-08-01

    With the increased focus on visual attention (VA) in the last decade, a large number of computational visual saliency methods have been developed over the past few years. These models are traditionally evaluated by using performance evaluation metrics that quantify the match between predicted saliency and fixation data obtained from eye-tracking experiments on human observers. Though a considerable number of such metrics have been proposed in the literature, there are notable problems in them. In this paper, we discuss shortcomings in the existing metrics through illustrative examples and propose a new metric that uses local weights based on fixation density, which overcomes these flaws. To compare the performance of our proposed metric at assessing the quality of saliency prediction with other existing metrics, we construct a ground-truth subjective database in which saliency maps obtained from 17 different VA models are evaluated by 16 human observers on a five-point categorical scale in terms of their visual resemblance with corresponding ground-truth fixation density maps obtained from eye-tracking data. The metrics are evaluated by correlating metric scores with the human subjective ratings. The correlation results show that the proposed evaluation metric outperforms all other popular existing metrics. In addition, the constructed database and corresponding subjective ratings provide an insight into which of the existing metrics and future metrics are better at estimating the quality of saliency prediction and can be used as a benchmark. PMID:27295671

  4. Basal forebrain motivational salience signal enhances cortical processing and decision speed.

    PubMed

    Raver, Sylvina M; Lin, Shih-Chieh

    2015-01-01

    The basal forebrain (BF) contains major projections to the cerebral cortex, and plays a well-documented role in arousal, attention, decision-making, and in modulating cortical activity. BF neuronal degeneration is an early event in Alzheimer's disease (AD) and dementias, and occurs in normal cognitive aging. While the BF is best known for its population of cortically projecting cholinergic neurons, the region is anatomically and neurochemically diverse, and also contains prominent populations of non-cholinergic projection neurons. In recent years, increasing attention has been dedicated to these non-cholinergic BF neurons in order to better understand how non-cholinergic BF circuits control cortical processing and behavioral performance. In this review, we focus on a unique population of putative non-cholinergic BF neurons that encodes the motivational salience of stimuli with a robust ensemble bursting response. We review recent studies that describe the specific physiological and functional characteristics of these BF salience-encoding neurons in behaving animals. These studies support the unifying hypothesis whereby BF salience-encoding neurons act as a gain modulation mechanism of the decision-making process to enhance cortical processing of behaviorally relevant stimuli, and thereby facilitate faster and more precise behavioral responses. This function of BF salience-encoding neurons represents a critical component in determining which incoming stimuli warrant an animal's attention, and is therefore a fundamental and early requirement of behavioral flexibility. PMID:26528157

  5. Basal forebrain motivational salience signal enhances cortical processing and decision speed

    PubMed Central

    Raver, Sylvina M.; Lin, Shih-Chieh

    2015-01-01

    The basal forebrain (BF) contains major projections to the cerebral cortex, and plays a well-documented role in arousal, attention, decision-making, and in modulating cortical activity. BF neuronal degeneration is an early event in Alzheimer’s disease (AD) and dementias, and occurs in normal cognitive aging. While the BF is best known for its population of cortically projecting cholinergic neurons, the region is anatomically and neurochemically diverse, and also contains prominent populations of non-cholinergic projection neurons. In recent years, increasing attention has been dedicated to these non-cholinergic BF neurons in order to better understand how non-cholinergic BF circuits control cortical processing and behavioral performance. In this review, we focus on a unique population of putative non-cholinergic BF neurons that encodes the motivational salience of stimuli with a robust ensemble bursting response. We review recent studies that describe the specific physiological and functional characteristics of these BF salience-encoding neurons in behaving animals. These studies support the unifying hypothesis whereby BF salience-encoding neurons act as a gain modulation mechanism of the decision-making process to enhance cortical processing of behaviorally relevant stimuli, and thereby facilitate faster and more precise behavioral responses. This function of BF salience-encoding neurons represents a critical component in determining which incoming stimuli warrant an animal’s attention, and is therefore a fundamental and early requirement of behavioral flexibility. PMID:26528157

  6. Aposematism: balancing salience and camouflage.

    PubMed

    Barnett, James B; Scott-Samuel, Nicholas E; Cuthill, Innes C

    2016-08-01

    Aposematic signals are often characterized by high conspicuousness. Larger and brighter signals reinforce avoidance learning, distinguish defended from palatable prey and are more easily memorized by predators. Conspicuous signalling, however, has costs: encounter rates with naive, specialized or nutritionally stressed predators are likely to increase. It has been suggested that intermediate levels of aposematic conspicuousness can evolve to balance deterrence and detectability, especially for moderately defended species. The effectiveness of such signals, however, has not yet been experimentally tested under field conditions. We used dough caterpillar-like baits to test whether reduced levels of aposematic conspicuousness can have survival benefits when predated by wild birds in natural conditions. Our results suggest that, when controlling for the number and intensity of internal contrast boundaries (stripes), a reduced-conspicuousness aposematic pattern can have a survival advantage over more conspicuous signals, as well as cryptic colours. Furthermore, we find a survival benefit from the addition of internal contrast for both high and low levels of conspicuousness. This adds ecological validity to evolutionary models of aposematic saliency and the evolution of honest signalling. PMID:27484645

  7. A Neural Computational Model of Incentive Salience

    PubMed Central

    Zhang, Jun; Berridge, Kent C.; Tindell, Amy J.; Smith, Kyle S.; Aldridge, J. Wayne

    2009-01-01

    Incentive salience is a motivational property with ‘magnet-like’ qualities. When attributed to reward-predicting stimuli (cues), incentive salience triggers a pulse of ‘wanting’ and an individual is pulled toward the cues and reward. A key computational question is how incentive salience is generated during a cue re-encounter, which combines both learning and the state of limbic brain mechanisms. Learning processes, such as temporal-difference models, provide one way for stimuli to acquire cached predictive values of rewards. However, empirical data show that subsequent incentive values are also modulated on the fly by dynamic fluctuation in physiological states, altering cached values in ways requiring additional motivation mechanisms. Dynamic modulation of incentive salience for a Pavlovian conditioned stimulus (CS or cue) occurs during certain states, without necessarily requiring (re)learning about the cue. In some cases, dynamic modulation of cue value occurs during states that are quite novel, never having been experienced before, and even prior to experience of the associated unconditioned reward in the new state. Such cases can include novel drug-induced mesolimbic activation and addictive incentive-sensitization, as well as natural appetite states such as salt appetite. Dynamic enhancement specifically raises the incentive salience of an appropriate CS, without necessarily changing that of other CSs. Here we suggest a new computational model that modulates incentive salience by integrating changing physiological states with prior learning. We support the model with behavioral and neurobiological data from empirical tests that demonstrate dynamic elevations in cue-triggered motivation (involving natural salt appetite, and drug-induced intoxication and sensitization). Our data call for a dynamic model of incentive salience, such as presented here. Computational models can adequately capture fluctuations in cue-triggered ‘wanting’ only by

  8. Damage to the Salience Network and Interactions with the Default Mode Network

    PubMed Central

    Jilka, Sagar R.; Scott, Gregory; Ham, Timothy; Pickering, Alan; Bonnelle, Valerie; Braga, Rodrigo M.; Leech, Robert

    2014-01-01

    Interactions between the Salience Network (SN) and the Default Mode Network (DMN) are thought to be important for cognitive control. However, evidence for a causal relationship between the networks is limited. Previously, we have reported that traumatic damage to white matter tracts within the SN predicts abnormal DMN function. Here we investigate the effect of this damage on network interactions that accompany changing motor control. We initially used fMRI of the Stop Signal Task to study response inhibition in humans. In healthy subjects, functional connectivity (FC) between the right anterior insula (rAI), a key node of the SN, and the DMN transiently increased during stopping. This change in FC was not seen in a group of traumatic brain injury (TBI) patients with impaired cognitive control. Furthermore, the amount of SN tract damage negatively correlated with FC between the networks. We confirmed these findings in a second group of TBI patients. Here, switching rather than inhibiting a motor response: (1) was accompanied by a similar increase in network FC in healthy controls; (2) was not seen in TBI patients; and (3) tract damage after TBI again correlated with FC breakdown. This shows that coupling between the rAI and DMN increases with cognitive control and that damage within the SN impairs this dynamic network interaction. This work provides compelling evidence for a model of cognitive control where the SN is involved in the attentional capture of salient external stimuli and signals the DMN to reduce its activity when attention is externally focused. PMID:25122883

  9. Visual Saliency Models for Text Detection in Real World

    PubMed Central

    Gao, Renwu; Uchida, Seiichi; Shahab, Asif; Shafait, Faisal; Frinken, Volkmar

    2014-01-01

    This paper evaluates the degree of saliency of texts in natural scenes using visual saliency models. A large scale scene image database with pixel level ground truth is created for this purpose. Using this scene image database and five state-of-the-art models, visual saliency maps that represent the degree of saliency of the objects are calculated. The receiver operating characteristic curve is employed in order to evaluate the saliency of scene texts, which is calculated by visual saliency models. A visualization of the distribution of scene texts and non-texts in the space constructed by three kinds of saliency maps, which are calculated using Itti's visual saliency model with intensity, color and orientation features, is given. This visualization of distribution indicates that text characters are more salient than their non-text neighbors, and can be captured from the background. Therefore, scene texts can be extracted from the scene images. With this in mind, a new visual saliency architecture, named hierarchical visual saliency model, is proposed. Hierarchical visual saliency model is based on Itti's model and consists of two stages. In the first stage, Itti's model is used to calculate the saliency map, and Otsu's global thresholding algorithm is applied to extract the salient region that we are interested in. In the second stage, Itti's model is applied to the salient region to calculate the final saliency map. An experimental evaluation demonstrates that the proposed model outperforms Itti's model in terms of captured scene texts. PMID:25494196

  10. Cortical thickness and oscillatory phase resetting: a proposed mechanism of salience network dysfunction in schizophrenia.

    PubMed

    Palaniyappan, L; Doege, K; Mallikarjun, P; Liddle, E; Francis-Liddle, P

    2012-01-01

    Schizophrenia is characterised by both electrophysiological abnormalities and consistent changes in the structure of cortical grey matter. But the relationship between these two observations is largely unknown. Structural changes reported in schizophrenia include reduced grey matter volume, thickness and surface area in several cortical regions, but most frequently in the insula and anterior cingulate cortex. These two regions together constitute an intrinsic brain circuit known as the "Salience Network", which has a key role in stimulus processing. During stimulus processing tasks, evoked activity is noted using electroencephalography (EEG). Phase resetting of ongoing oscillations contributes to this evoked activity. Neuronal oscillations play a crucial role in cerebral recruitment during cognitive tasks, and influencing the oscillatory phase can modulate cortical excitability and the transition between various cognitive states. At a network level, such a transition or switch is thought to be enabled by the Salience Network. In this study, we investigated the relationship between the cortical thickness in the Salience Network (measured using MRI) and the degree of phase resetting observed during an oddball task (measured using EEG) in 18 medicated male patients in a clinically stable phase of schizophrenia and 20 age and gender matched healthy controls. We obtained a measure of partial phase resetting after a stimulus is presented, and a second measure representing mean evoked activity, using the methods proposed by Martinez-Montes. Using MRI analysis, we have firstly shown that there is a significant loss of cortical thickness of regions that constitute the Salience Network in patients with schizophrenia. EEG analysis revealed that in healthy controls, the expected relationship between phase resetting and evoked electrical activity is observed, but in patients with schizophrenia the theta phase resetting is a weak predictor of the activity evoked by attending to

  11. Learning based saliency weighted structural similarity

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoliang; Liu, Xiaolin

    2012-01-01

    Image quality assessment (IQA) is a critical issue in image processing applications, but commonly used criterions for image quality assessment do not map well with perceived quality. The recently proposed structural similarity (SSIM) is regarded as an excellent work in image quality assessment criterions, but it only consider local information and ignore some important global concepts. Based on the SSIM image quality assessment criterion and the detection of visual saliency in image, this paper proposes a learning based saliency weighted structural similarity IQA criterion. The algorithm combines the SSIM index and saliency map in a machine learning framework to learn a mapping from these features to perceived image quality. Experiments on a standard image quality assessment database show that our algorithm performs better than commonly used criterions, and our algorithm captures results which correlate well with subjective judgments of image quality.

  12. 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

  13. Benchmark three-dimensional eye-tracking dataset for visual saliency prediction on stereoscopic three-dimensional video

    NASA Astrophysics Data System (ADS)

    Banitalebi-Dehkordi, Amin; Nasiopoulos, Eleni; Pourazad, Mahsa T.; Nasiopoulos, Panos

    2016-01-01

    Visual attention models (VAMs) predict the location of image or video regions that are most likely to attract human attention. Although saliency detection is well explored for two-dimensional (2-D) image and video content, there have been only a few attempts made to design three-dimensional (3-D) saliency prediction models. Newly proposed 3-D VAMs have to be validated over large-scale video saliency prediction datasets, which also contain results of eye-tracking information. There are several publicly available eye-tracking datasets for 2-D image and video content. In the case of 3-D, however, there is still a need for large-scale video saliency datasets for the research community for validating different 3-D VAMs. We introduce a large-scale dataset containing eye-tracking data collected from 61 stereoscopic 3-D videos (and also 2-D versions of those), and 24 subjects participated in a free-viewing test. We evaluate the performance of the existing saliency detection methods over the proposed dataset. In addition, we created an online benchmark for validating the performance of the existing 2-D and 3-D VAMs and facilitating the addition of new VAMs to the benchmark. Our benchmark currently contains 50 different VAMs.

  14. Emotional Intelligence, Identity Salience, and Metaphors. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on emotional intelligence, identity salience, and metaphors in human resource development (HRD). "Applying Client and Consultant Generated Metaphors in HRD: Lessons from Psychotherapy" (Darren Short) reviews some techniques that psychotherapists have devised for using their own metaphors and the…

  15. Career Salience of Institutionalized Adolescent Offenders.

    ERIC Educational Resources Information Center

    Munson, Wayne W.; Strauss, Christine F.

    1993-01-01

    Investigated self-esteem and career salience of institutionalized male adolescent offenders (n=185) in context of Super's lifespan career development theory. Results indicated that participation, commitment, and values expectations in home-family roles contributed significantly to self-esteem in adolescent offenders. Adolescent offenders differed…

  16. Referent Salience Affects Second Language Article Use

    ERIC Educational Resources Information Center

    Trenkic, Danijela; Pongpairoj, Nattama

    2013-01-01

    The effect of referent salience on second language (L2) article production in real time was explored. Thai (-articles) and French (+articles) learners of English described dynamic events involving two referents, one visually cued to be more salient at the point of utterance formulation. Definiteness marking was made communicatively redundant with…

  17. A computational visual saliency model based on statistics and machine learning.

    PubMed

    Lin, Ru-Je; Lin, Wei-Song

    2014-01-01

    Identifying the type of stimuli that attracts human visual attention has been an appealing topic for scientists for many years. In particular, marking the salient regions in images is useful for both psychologists and many computer vision applications. In this paper, we propose a computational approach for producing saliency maps using statistics and machine learning methods. Based on four assumptions, three properties (Feature-Prior, Position-Prior, and Feature-Distribution) can be derived and combined by a simple intersection operation to obtain a saliency map. These properties are implemented by a similarity computation, support vector regression (SVR) technique, statistical analysis of training samples, and information theory using low-level features. This technique is able to learn the preferences of human visual behavior while simultaneously considering feature uniqueness. Experimental results show that our approach performs better in predicting human visual attention regions than 12 other models in two test databases. PMID:25084782

  18. Weighted-MSE based on saliency map for assessing video quality of H.264 video streams

    NASA Astrophysics Data System (ADS)

    Boujut, H.; Benois-Pineau, J.; Hadar, O.; Ahmed, T.; Bonnet, P.

    2011-01-01

    Human vision system is very complex and has been studied for many years specifically for purposes of efficient encoding of visual, e.g. video content from digital TV. There have been physiological and psychological evidences which indicate that viewers do not pay equal attention to all exposed visual information, but only focus on certain areas known as focus of attention (FOA) or saliency regions. In this work, we propose a novel based objective quality assessment metric, for assessing the perceptual quality of decoded video sequences affected by transmission errors and packed loses. The proposed method weights the Mean Square Error (MSE), Weighted-MSE (WMSE), according to the calculated saliency map at each pixel. Our method was validated trough subjective quality experiments.

  19. Saliency detection based on multi-instance images learning

    NASA Astrophysics Data System (ADS)

    Wan, Shouhong; Jin, Peiquan; Yue, Lihua; Huang, Qian

    2015-07-01

    Existing visual saliency detection methods are usually based on single image, however, without priori knowledge, the contents of single image are ambiguous, so visual saliency detection based on single image can't extract region of interest. To solve it, we propose a novel saliency detection based on multi-instance images. Our method considers human's visual psychological factors and measures visual saliency based on global contrast, local contrast and sparsity. It firstly uses multi-instance learning to get the center of clustering, and then computes feature relative dispersion. By fusing different weighted feature saliency map, the final synthesize saliency map is generated. Comparing with other saliency detection methods, our method increases the rate of hit.

  20. Fast full resolution saliency detection based on incoherent imaging system

    NASA Astrophysics Data System (ADS)

    Lin, Guang; Zhao, Jufeng; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2016-05-01

    Image saliency detection is widely applied in many tasks in the field of the computer vision. In this paper, we combine the saliency detection with the Fourier optics to achieve acceleration of saliency detection algorithm. An actual optical saliency detection system is constructed within the framework of incoherent imaging system. Additionally, the application of our system to implement the bottom-up rapid pre-saliency process of primate visual saliency is discussed with dual-resolution camera. A set of experiments over our system are conducted and discussed. We also demonstrate the comparisons between our method and pure computer methods. The results show our system can produce full resolution saliency maps faster and more effective.

  1. Saliency detection for videos using 3D FFT local spectra

    NASA Astrophysics Data System (ADS)

    Long, Zhiling; AlRegib, Ghassan

    2015-03-01

    Bottom-up spatio-temporal saliency detection identifies perceptually important regions of interest in video sequences. The center-surround model proves to be useful for visual saliency detection. In this work, we explore using 3D FFT local spectra as features for saliency detection within the center-surround framework. We develop a spectral location based decomposition scheme to divide a 3D FFT cube into two components, one related to temporal changes and the other related to spatial changes. Temporal saliency and spatial saliency are detected separately using features derived from each spectral component through a simple center-surround comparison method. The two detection results are then combined to yield a saliency map. We apply the same detection algorithm to different color channels (YIQ) and incorporate the results into the final saliency determination. The proposed technique is tested with the public CRCNS database. Both visual and numerical evaluations verify the promising performance of our technique.

  2. Fast full resolution saliency detection based on incoherent imaging system

    NASA Astrophysics Data System (ADS)

    Lin, Guang; Zhao, Jufeng; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2016-08-01

    Image saliency detection is widely applied in many tasks in the field of the computer vision. In this paper, we combine the saliency detection with the Fourier optics to achieve acceleration of saliency detection algorithm. An actual optical saliency detection system is constructed within the framework of incoherent imaging system. Additionally, the application of our system to implement the bottom-up rapid pre-saliency process of primate visual saliency is discussed with dual-resolution camera. A set of experiments over our system are conducted and discussed. We also demonstrate the comparisons between our method and pure computer methods. The results show our system can produce full resolution saliency maps faster and more effective.

  3. Saliency mapping in the optic tectum and its relationship to habituation.

    PubMed

    Dutta, Arkadeb; Gutfreund, Yoram

    2014-01-01

    Habituation of the orienting response has long served as a model system for studying fundamental psychological phenomena such as learning, attention, decisions, and surprise. In this article, we review an emerging hypothesis that the evolutionary role of the superior colliculus (SC) in mammals or its homolog in birds, the optic tectum (OT), is to select the most salient target and send this information to the appropriate brain regions to control the body and brain orienting responses. Recent studies have begun to reveal mechanisms of how saliency is computed in the OT/SC, demonstrating a striking similarity between mammals and birds. The saliency of a target can be determined by how different it is from the surrounding objects, by how different it is from its history (that is habituation) and by how relevant it is for the task at hand. Here, we will first review evidence, mostly from primates and barn owls, that all three types of saliency computations are linked in the OT/SC. We will then focus more on neural adaptation in the OT and its possible link to temporal saliency and habituation. PMID:24474908

  4. Bottom-Up Visual Saliency Estimation With Deep Autoencoder-Based Sparse Reconstruction.

    PubMed

    Xia, Chen; Qi, Fei; Shi, Guangming

    2016-06-01

    Research on visual perception indicates that the human visual system is sensitive to center-surround (C-S) contrast in the bottom-up saliency-driven attention process. Different from the traditional contrast computation of feature difference, models based on reconstruction have emerged to estimate saliency by starting from original images themselves instead of seeking for certain ad hoc features. However, in the existing reconstruction-based methods, the reconstruction parameters of each area are calculated independently without taking their global correlation into account. In this paper, inspired by the powerful feature learning and data reconstruction ability of deep autoencoders, we construct a deep C-S inference network and train it with the data sampled randomly from the entire image to obtain a unified reconstruction pattern for the current image. In this way, global competition in sampling and learning processes can be integrated into the nonlocal reconstruction and saliency estimation of each pixel, which can achieve better detection results than the models with separate consideration on local and global rarity. Moreover, by learning from the current scene, the proposed model can achieve the feature extraction and interaction simultaneously in an adaptive way, which can form a better generalization ability to handle more types of stimuli. Experimental results show that in accordance with different inputs, the network can learn distinct basic features for saliency modeling in its code layer. Furthermore, in a comprehensive evaluation on several benchmark data sets, the proposed method can outperform the existing state-of-the-art algorithms. PMID:26800552

  5. Saliency mapping in the optic tectum and its relationship to habituation

    PubMed Central

    Dutta, Arkadeb; Gutfreund, Yoram

    2014-01-01

    Habituation of the orienting response has long served as a model system for studying fundamental psychological phenomena such as learning, attention, decisions, and surprise. In this article, we review an emerging hypothesis that the evolutionary role of the superior colliculus (SC) in mammals or its homolog in birds, the optic tectum (OT), is to select the most salient target and send this information to the appropriate brain regions to control the body and brain orienting responses. Recent studies have begun to reveal mechanisms of how saliency is computed in the OT/SC, demonstrating a striking similarity between mammals and birds. The saliency of a target can be determined by how different it is from the surrounding objects, by how different it is from its history (that is habituation) and by how relevant it is for the task at hand. Here, we will first review evidence, mostly from primates and barn owls, that all three types of saliency computations are linked in the OT/SC. We will then focus more on neural adaptation in the OT and its possible link to temporal saliency and habituation. PMID:24474908

  6. Fusion of infrared and visible images based on saliency scale-space in frequency domain

    NASA Astrophysics Data System (ADS)

    Chen, Yanfei; Sang, Nong; Dan, Zhiping

    2015-12-01

    A fusion algorithm of infrared and visible images based on saliency scale-space in the frequency domain was proposed. Focus of human attention is directed towards the salient targets which interpret the most important information in the image. For the given registered infrared and visible images, firstly, visual features are extracted to obtain the input hypercomplex matrix. Secondly, the Hypercomplex Fourier Transform (HFT) is used to obtain the salient regions of the infrared and visible images respectively, the convolution of the input hypercomplex matrix amplitude spectrum with a low-pass Gaussian kernel of an appropriate scale which is equivalent to an image saliency detector are done. The saliency maps are obtained by reconstructing the 2D signal using the original phase and the amplitude spectrum, filtered at a scale selected by minimizing saliency map entropy. Thirdly, the salient regions are fused with the adoptive weighting fusion rules, and the nonsalient regions are fused with the rule based on region energy (RE) and region sharpness (RS), then the fused image is obtained. Experimental results show that the presented algorithm can hold high spectrum information of the visual image, and effectively get the thermal targets information at different scales of the infrared image.

  7. Competition between Visual Events Modulates the Influence of Salience during Free-Viewing of Naturalistic Videos

    PubMed Central

    Nardo, Davide; Console, Paola; Reverberi, Carlo; Macaluso, Emiliano

    2016-01-01

    In daily life the brain is exposed to a large amount of external signals that compete for processing resources. The attentional system can select relevant information based on many possible combinations of goal-directed and stimulus-driven control signals. Here, we investigate the behavioral and physiological effects of competition between distinctive visual events during free-viewing of naturalistic videos. Nineteen healthy subjects underwent functional magnetic resonance imaging (fMRI) while viewing short video-clips of everyday life situations, without any explicit goal-directed task. Each video contained either a single semantically-relevant event on the left or right side (Lat-trials), or multiple distinctive events in both hemifields (Multi-trials). For each video, we computed a salience index to quantify the lateralization bias due to stimulus-driven signals, and a gaze index (based on eye-tracking data) to quantify the efficacy of the stimuli in capturing attention to either side. Behaviorally, our results showed that stimulus-driven salience influenced spatial orienting only in presence of multiple competing events (Multi-trials). fMRI results showed that the processing of competing events engaged the ventral attention network, including the right temporoparietal junction (R TPJ) and the right inferior frontal cortex. Salience was found to modulate activity in the visual cortex, but only in the presence of competing events; while the orienting efficacy of Multi-trials affected activity in both the visual cortex and posterior parietal cortex (PPC). We conclude that in presence of multiple competing events, the ventral attention system detects semantically-relevant events, while regions of the dorsal system make use of saliency signals to select relevant locations and guide spatial orienting. PMID:27445760

  8. Complementary effects of gaze direction and early saliency in guiding fixations during free viewing.

    PubMed

    Borji, Ali; Parks, Daniel; Itti, Laurent

    2014-01-01

    Gaze direction provides an important and ubiquitous communication channel in daily behavior and social interaction of humans and some animals. While several studies have addressed gaze direction in synthesized simple scenes, few have examined how it can bias observer attention and how it might interact with early saliency during free viewing of natural and realistic scenes. Experiment 1 used a controlled, staged setting in which an actor was asked to look at two different objects in turn, yielding two images that differed only by the actor's gaze direction, to causally assess the effects of actor gaze direction. Over all scenes, the median probability of following an actor's gaze direction was higher than the median probability of looking toward the single most salient location, and higher than chance. Experiment 2 confirmed these findings over a larger set of unconstrained scenes collected from the Web and containing people looking at objects and/or other people. To further compare the strength of saliency versus gaze direction cues, we computed gaze maps by drawing a cone in the direction of gaze of the actors present in the images. Gaze maps predicted observers' fixation locations significantly above chance, although below saliency. Finally, to gauge the relative importance of actor face and eye directions in guiding observer's fixations, in Experiment 3, observers were asked to guess the gaze direction from only an actor's face region (with the rest of the scene masked), in two conditions: actor eyes visible or masked. Median probability of guessing the true gaze direction within ±9° was significantly higher when eyes were visible, suggesting that the eyes contribute significantly to gaze estimation, in addition to face region. Our results highlight that gaze direction is a strong attentional cue in guiding eye movements, complementing low-level saliency cues, and derived from both face and eyes of actors in the scene. Thus gaze direction should be considered

  9. A novel multiresolution spatiotemporal saliency detection model and its applications in image and video compression.

    PubMed

    Guo, Chenlei; Zhang, Liming

    2010-01-01

    Salient areas in natural scenes are generally regarded as areas which the human eye will typically focus on, and finding these areas is the key step in object detection. In computer vision, many models have been proposed to simulate the behavior of eyes such as SaliencyToolBox (STB), Neuromorphic Vision Toolkit (NVT), and others, but they demand high computational cost and computing useful results mostly relies on their choice of parameters. Although some region-based approaches were proposed to reduce the computational complexity of feature maps, these approaches still were not able to work in real time. Recently, a simple and fast approach called spectral residual (SR) was proposed, which uses the SR of the amplitude spectrum to calculate the image's saliency map. However, in our previous work, we pointed out that it is the phase spectrum, not the amplitude spectrum, of an image's Fourier transform that is key to calculating the location of salient areas, and proposed the phase spectrum of Fourier transform (PFT) model. In this paper, we present a quaternion representation of an image which is composed of intensity, color, and motion features. Based on the principle of PFT, a novel multiresolution spatiotemporal saliency detection model called phase spectrum of quaternion Fourier transform (PQFT) is proposed in this paper to calculate the spatiotemporal saliency map of an image by its quaternion representation. Distinct from other models, the added motion dimension allows the phase spectrum to represent spatiotemporal saliency in order to perform attention selection not only for images but also for videos. In addition, the PQFT model can compute the saliency map of an image under various resolutions from coarse to fine. Therefore, the hierarchical selectivity (HS) framework based on the PQFT model is introduced here to construct the tree structure representation of an image. With the help of HS, a model called multiresolution wavelet domain foveation (MWDF) is

  10. Adaptive Metric Learning for Saliency Detection.

    PubMed

    Li, Shuang; Lu, Huchuan; Lin, Zhe; Shen, Xiaohui; Price, Brian

    2015-11-01

    In this paper, we propose a novel adaptive metric learning algorithm (AML) for visual saliency detection. A key observation is that the saliency of a superpixel can be estimated by the distance from the most certain foreground and background seeds. Instead of measuring distance on the Euclidean space, we present a learning method based on two complementary Mahalanobis distance metrics: 1) generic metric learning (GML) and 2) specific metric learning (SML). GML aims at the global distribution of the whole training set, while SML considers the specific structure of a single image. Considering that multiple similarity measures from different views may enhance the relevant information and alleviate the irrelevant one, we try to fuse the GML and SML together and experimentally find the combining result does work well. Different from the most existing methods which are directly based on low-level features, we devise a superpixelwise Fisher vector coding approach to better distinguish salient objects from the background. We also propose an accurate seeds selection mechanism and exploit contextual and multiscale information when constructing the final saliency map. Experimental results on various image sets show that the proposed AML performs favorably against the state-of-the-arts. PMID:26054067

  11. Data-driven approach to dynamic visual attention modelling

    NASA Astrophysics Data System (ADS)

    Culibrk, Dubravko; Sladojevic, Srdjan; Riche, Nicolas; Mancas, Matei; Crnojevic, Vladimir

    2012-06-01

    Visual attention deployment mechanisms allow the Human Visual System to cope with an overwhelming amount of visual data by dedicating most of the processing power to objects of interest. The ability to automatically detect areas of the visual scene that will be attended to by humans is of interest for a large number of applications, from video coding, video quality assessment to scene understanding. Due to this fact, visual saliency (bottom-up attention) models have generated significant scientific interest in recent years. Most recent work in this area deals with dynamic models of attention that deal with moving stimuli (videos) instead of traditionally used still images. Visual saliency models are usually evaluated against ground-truth eye-tracking data collected from human subjects. However, there are precious few recently published approaches that try to learn saliency from eyetracking data and, to the best of our knowledge, no approaches that try to do so when dynamic saliency is concerned. The paper attempts to fill this gap and describes an approach to data-driven dynamic saliency model learning. A framework is proposed that enables the use of eye-tracking data to train an arbitrary machine learning algorithm, using arbitrary features derived from the scene. We evaluate the methodology using features from a state-of-the art dynamic saliency model and show how simple machine learning algorithms can be trained to distinguish between visually salient and non-salient parts of the scene.

  12. The Structure of the Relationship between Attention and Intelligence

    ERIC Educational Resources Information Center

    Schweizer, Karl; Moosbrugger, Helfried; Goldhammer, Frank

    2005-01-01

    The relationship between attention and general intelligence was investigated considering the different types of attention: alertness, sustained attention, focused attention, attentional switching, divided attention, attention according to the supervisory attentional system, attention as inhibition, spatial attention, attention as planning,…

  13. Neural activities in v1 create a bottom-up saliency map.

    PubMed

    Zhang, Xilin; Zhaoping, Li; Zhou, Tiangang; Fang, Fang

    2012-01-12

    The bottom-up contribution to the allocation of exogenous attention is a saliency map, whose neural substrate is hard to identify because of possible contamination by top-down signals. We obviated this possibility using stimuli that observers could not perceive, but that nevertheless, through orientation contrast between foreground and background regions, attracted attention to improve a localized visual discrimination. When orientation contrast increased, so did the degree of attraction, and two physiological measures: the amplitude of the earliest (C1) component of the ERP, which is associated with primary visual cortex, and fMRI BOLD signals in areas V1-V4 (but not the intraparietal sulcus). Significantly, across observers, the degree of attraction correlated with the C1 amplitude and just the V1 BOLD signal. These findings strongly support the proposal that a bottom-up saliency map is created in V1, challenging the dominant view that the saliency map is generated in the parietal cortex. PMID:22243756

  14. Fast cat-eye effect target recognition based on saliency extraction

    NASA Astrophysics Data System (ADS)

    Li, Li; Ren, Jianlin; Wang, Xingbin

    2015-09-01

    Background complexity is a main reason that results in false detection in cat-eye target recognition. Human vision has selective attention property which can help search the salient target from complex unknown scenes quickly and precisely. In the paper, we propose a novel cat-eye effect target recognition method named Multi-channel Saliency Processing before Fusion (MSPF). This method combines traditional cat-eye target recognition with the selective characters of visual attention. Furthermore, parallel processing enables it to achieve fast recognition. Experimental results show that the proposed method performs better in accuracy, robustness and speed compared to other methods.

  15. Multi-window visual saliency extraction for fusion of visible and infrared images

    NASA Astrophysics Data System (ADS)

    Zhao, Jufeng; Gao, Xiumin; Chen, Yueting; Feng, Huajun; Wang, Daodang

    2016-05-01

    Fusion for visible and infrared images aims to combine the source images of the same scene into a single image with more feature information and better visual performance. In this paper, the authors propose a fusion method based on multi-window visual saliency extraction for visible and infrared images. To extract feature information from infrared and visible images, we design local-window-based frequency-tuned method. With this idea, visual saliency maps are calculated for variable feature information under different local window. These maps show the weights of people's attention upon images for each pixel and region. Enhanced fusion is done using simple weight combination way. Compared with the classical and state-of-the-art approaches, the experimental results demonstrate the proposed approach runs efficiently and performs better than other methods, especially in visual performance and details enhancement.

  16. Investigating bottom-up auditory attention

    PubMed Central

    Kaya, Emine Merve; Elhilali, Mounya

    2014-01-01

    Bottom-up attention is a sensory-driven selection mechanism that directs perception toward a subset of the stimulus that is considered salient, or attention-grabbing. Most studies of bottom-up auditory attention have adapted frameworks similar to visual attention models whereby local or global “contrast” is a central concept in defining salient elements in a scene. In the current study, we take a more fundamental approach to modeling auditory attention; providing the first examination of the space of auditory saliency spanning pitch, intensity and timbre; and shedding light on complex interactions among these features. Informed by psychoacoustic results, we develop a computational model of auditory saliency implementing a novel attentional framework, guided by processes hypothesized to take place in the auditory pathway. In particular, the model tests the hypothesis that perception tracks the evolution of sound events in a multidimensional feature space, and flags any deviation from background statistics as salient. Predictions from the model corroborate the relationship between bottom-up auditory attention and statistical inference, and argues for a potential role of predictive coding as mechanism for saliency detection in acoustic scenes. PMID:24904367

  17. Learning to Model Task-Oriented Attention.

    PubMed

    Zou, Xiaochun; Zhao, Xinbo; Wang, Jian; Yang, Yongjia

    2016-01-01

    For many applications in graphics, design, and human computer interaction, it is essential to understand where humans look in a scene with a particular task. Models of saliency can be used to predict fixation locations, but a large body of previous saliency models focused on free-viewing task. They are based on bottom-up computation that does not consider task-oriented image semantics and often does not match actual eye movements. To address this problem, we collected eye tracking data of 11 subjects when they performed some particular search task in 1307 images and annotation data of 2,511 segmented objects with fine contours and 8 semantic attributes. Using this database as training and testing examples, we learn a model of saliency based on bottom-up image features and target position feature. Experimental results demonstrate the importance of the target information in the prediction of task-oriented visual attention. PMID:27247561

  18. Learning to Model Task-Oriented Attention

    PubMed Central

    Zou, Xiaochun; Zhao, Xinbo; Wang, Jian; Yang, Yongjia

    2016-01-01

    For many applications in graphics, design, and human computer interaction, it is essential to understand where humans look in a scene with a particular task. Models of saliency can be used to predict fixation locations, but a large body of previous saliency models focused on free-viewing task. They are based on bottom-up computation that does not consider task-oriented image semantics and often does not match actual eye movements. To address this problem, we collected eye tracking data of 11 subjects when they performed some particular search task in 1307 images and annotation data of 2,511 segmented objects with fine contours and 8 semantic attributes. Using this database as training and testing examples, we learn a model of saliency based on bottom-up image features and target position feature. Experimental results demonstrate the importance of the target information in the prediction of task-oriented visual attention. PMID:27247561

  19. Subthalamic nucleus stimulation affects incentive salience attribution in Parkinson's disease.

    PubMed

    Serranová, Tereza; Jech, Robert; Dušek, Petr; Sieger, Tomáš; Růžička, Filip; Urgošík, Dušan; Růžička, Evžen

    2011-10-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) can induce nonmotor side effects such as behavioral and mood disturbances or body weight gain in Parkinson's disease (PD) patients. We hypothesized that some of these problems could be related to an altered attribution of incentive salience (ie, emotional relevance) to rewarding and aversive stimuli. Twenty PD patients (all men; mean age ± SD, 58.3 ± 6 years) in bilateral STN DBS switched ON and OFF conditions and 18 matched controls rated pictures selected from the International Affective Picture System according to emotional valence (unpleasantness/pleasantness) and arousal on 2 independent visual scales ranging from 1 to 9. Eighty-four pictures depicting primary rewarding (erotica and food) and aversive fearful (victims and threat) and neutral stimuli were selected for this study. In the STN DBS ON condition, the PD patients attributed lower valence scores to the aversive pictures compared with the OFF condition (P < .01) and compared with controls (P < .01). The difference between the OFF condition and controls was less pronounced (P < .05). Furthermore, postoperative weight gain correlated with arousal ratings from the food pictures in the STN DBS ON condition (P < .05 compensated for OFF condition). Our results suggest that STN DBS increases activation of the aversive motivational system so that more relevance is attributed to aversive fearful stimuli. In addition, STN DBS-related sensitivity to food reward stimuli cues might drive DBS-treated patients to higher food intake and subsequent weight gain. PMID:21780183

  20. Response variability of frontal eye field neurons modulates with sensory input and saccade preparation but not visual search salience.

    PubMed

    Purcell, Braden A; Heitz, Richard P; Cohen, Jeremiah Y; Schall, Jeffrey D

    2012-11-01

    Discharge rate modulation of frontal eye field (FEF) neurons has been identified with a representation of visual search salience (physical conspicuity and behavioral relevance) and saccade preparation. We tested whether salience or saccade preparation are evident in the trial-to-trial variability of discharge rate. We quantified response variability via the Fano factor in FEF neurons recorded in monkeys performing efficient and inefficient visual search tasks. Response variability declined following stimulus presentation in most neurons, but despite clear discharge rate modulation, variability did not change with target salience. Instead, we found that response variability was modulated by stimulus luminance and the number of items in the visual field independently of attentional demands. Response variability declined to a minimum before saccade initiation, and presaccadic response variability was directionally tuned. In addition, response variability was correlated with the response time of memory-guided saccades. These results indicate that the trial-by-trial response variability of FEF neurons reflects saccade preparation and the strength of sensory input, but not visual search salience or attentional allocation. PMID:22956785

  1. Cognition, emotion, and attention.

    PubMed

    Müller-Oehring, Eva M; Schulte, Tilman

    2014-01-01

    Deficits of attention, emotion, and cognition occur in individuals with alcohol abuse and addiction. This review elucidates the concepts of attention, emotion, and cognition and references research on the underlying neural networks and their compromise in alcohol use disorder. Neuroimaging research on adolescents with family history of alcoholism contributes to the understanding of pre-existing brain structural conditions and characterization of cognition and attention processes in high-risk individuals. Attention and cognition interact with other brain functions, including perceptual selection, salience, emotion, reward, and memory, through interconnected neural networks. Recent research reports compromised microstructural and functional network connectivity in alcoholism, which can have an effect on the dynamic tuning between brain systems, e.g., the frontally based executive control system, the limbic emotion system, and the midbrain-striatal reward system, thereby impeding cognitive flexibility and behavioral adaptation to changing environments. Finally, we introduce concepts of functional compensation, the capacity to generate attentional resources for performance enhancement, and brain structure recovery with abstinence. An understanding of the neural mechanisms of attention, emotion, and cognition will likely provide the basis for better treatment strategies for developing skills that enhance alcoholism therapy adherence and quality of life, and reduce the propensity for relapse. PMID:25307584

  2. The Aberrant Salience Inventory: A New Measure of Psychosis Proneness

    ERIC Educational Resources Information Center

    Cicero, David C.; Kerns, John G.; McCarthy, Denis M.

    2010-01-01

    Aberrant salience is the unusual or incorrect assignment of salience, significance, or importance to otherwise innocuous stimuli and has been hypothesized to be important for psychosis and psychotic disorders such as schizophrenia. Despite the importance of this concept in psychosis research, no questionnaire measures are available to assess…

  3. Career Concerns, Values, and Role Salience in Employed Men.

    ERIC Educational Resources Information Center

    Duarte, M. Eduarda

    1995-01-01

    Tests Super's model of career adaptability by examining the relationship between career development concerns, values, and role salience among cement factory workers (n=881). They responded to the Adult Career Concerns Inventory, the Values Inventory, and the Salience Inventory. Results supported both Super's model of career adaptation and his…

  4. The Role of Ethnic School Segregation for Adolescents' Religious Salience

    ERIC Educational Resources Information Center

    Van der Bracht, Koen; D'hondt, Fanny; Van Houtte, Mieke; Van de Putte, Bart; Stevens, Peter A. J.

    2016-01-01

    Public concerns over the possible effects of school segregation on immigrant and ethnic majority religiosity have been on the rise over the last few years. In this paper we focus on (1) the association between ethnic school composition and religious salience, (2) intergenerational differences in religious salience and (3) the role of ethnic school…

  5. A Selective Insular Perfusion Deficit Contributes to Compromised Salience Network Connectivity in Recovering Alcoholic Men

    PubMed Central

    Sullivan, Edith V.; Müller-Oehring, Eva; Pitel, Anne-Lise; Chanraud, Sandra; Shankaranarayanan, Ajit; Alsop, David C.; Rohlfing, Torsten; Pfefferbaum, Adolf

    2013-01-01

    Background Alcoholism can disrupt neural synchrony between nodes of intrinsic functional networks that are maximally active when resting relative to engaging in a task, the default mode network (DMN) pattern. Untested, however, are whether the DMN in alcoholics can rebound normally from the relatively depressed task-state to the active resting-state and whether local perfusion deficits could disrupt network synchrony when switching from conditions of rest to task to rest, thereby indicating a physiological mechanism of neural network adaptation capability. Methods Whole-brain, 3D pulsed-continuous arterial spin labeling (PCASL) provided measurements of regional cerebral blood flow (rCBF) in 12 alcoholics and 12 controls under three conditions: pre-task rest, spatial working-memory task, post-task rest. Results With practice, alcoholics and controls achieved similar task accuracy and reaction times. Both groups exhibited a high-low-high pattern of perfusion levels in DMN regions during the rest-task-rest runs and the opposite pattern in posterior and cerebellar regions known to be associated with spatial working memory. Alcoholics showed selective differences from controls in the rest-task-rest CBF pattern in the anterior precuneus and CBF level in the insula, a hub of the salience network. Connectivity analysis identified activation synchrony from an insula seed to salience nodes (parietal, medial frontal, anterior cingulate cortices) in controls only. Conclusions We propose that attenuated insular CBF is a mechanism underlying compromised connectivity among salience network nodes. This local perfusion deficit in alcoholics has the potential to impair ability to switch from cognitive states of interoceptive cravings to cognitive control for curbing internal urges. PMID:23587427

  6. Visual attention on the sphere.

    PubMed

    Bogdanova, Iva; Bur, Alexandre; Hugli, Heinz

    2008-11-01

    Human visual system makes an extensive use of visual attention in order to select the most relevant information and speed-up the vision process. Inspired by visual attention, several computer models have been developed and many computer vision applications rely today on such models. However, the actual algorithms are not suitable to omnidirectional images, which contain a significant amount of geometrical distortion. In this paper, we present a novel computational approach that performs in spherical geometry and thus is suitable for omnidirectional images. Following one of the actual models of visual attention, the spherical saliency map is obtained by fusing together intensity, chromatic, and orientation spherical cue conspicuity maps that are themselves obtained through multiscale analysis on the sphere. Finally, the consecutive maxima in the spherical saliency map represent the spots of attention on the sphere. In the experimental part, the proposed method is then compared to the standard one using a synthetic image. Also, we provide examples of spots detection in real omnidirectional scenes which show its advantages. Finally, an experiment illustrates the homogeneity of the detected visual attention in omnidirectional images. PMID:18854253

  7. Working memory capacity accounts for the ability to switch between object-based and location-based allocation of visual attention.

    PubMed

    Bleckley, M Kathryn; Foster, Jeffrey L; Engle, Randall W

    2015-04-01

    Bleckley, Durso, Crutchfield, Engle, and Khanna (Psychonomic Bulletin & Review, 10, 884-889, 2003) found that visual attention allocation differed between groups high or low in working memory capacity (WMC). High-span, but not low-span, subjects showed an invalid-cue cost during a letter localization task in which the letter appeared closer to fixation than the cue, but not when the letter appeared farther from fixation than the cue. This suggests that low-spans allocated attention as a spotlight, whereas high-spans allocated their attention to objects. In this study, we tested whether utilizing object-based visual attention is a resource-limited process that is difficult for low-span individuals. In the first experiment, we tested the uses of object versus location-based attention with high and low-span subjects, with half of the subjects completing a demanding secondary load task. Under load, high-spans were no longer able to use object-based visual attention. A second experiment supported the hypothesis that these differences in allocation were due to high-spans using object-based allocation, whereas low-spans used location-based allocation. PMID:25421317

  8. Using Saliency-Weighted Disparity Statistics for Objective Visual Comfort Assessment of Stereoscopic Images

    NASA Astrophysics Data System (ADS)

    Zhang, Wenlan; Luo, Ting; Jiang, Gangyi; Jiang, Qiuping; Ying, Hongwei; Lu, Jing

    2016-06-01

    Visual comfort assessment (VCA) for stereoscopic images is a particularly significant yet challenging task in 3D quality of experience research field. Although the subjective assessment given by human observers is known as the most reliable way to evaluate the experienced visual discomfort, it is time-consuming and non-systematic. Therefore, it is of great importance to develop objective VCA approaches that can faithfully predict the degree of visual discomfort as human beings do. In this paper, a novel two-stage objective VCA framework is proposed. The main contribution of this study is that the important visual attention mechanism of human visual system is incorporated for visual comfort-aware feature extraction. Specifically, in the first stage, we first construct an adaptive 3D visual saliency detection model to derive saliency map of a stereoscopic image, and then a set of saliency-weighted disparity statistics are computed and combined to form a single feature vector to represent a stereoscopic image in terms of visual comfort. In the second stage, a high dimensional feature vector is fused into a single visual comfort score by performing random forest algorithm. Experimental results on two benchmark databases confirm the superior performance of the proposed approach.

  9. Reward salience and risk aversion underlie differential ACC activity in substance dependence

    PubMed Central

    Alexander, William H.; Fukunaga, Rena; Finn, Peter; Brown, Joshua W.

    2015-01-01

    The medial prefrontal cortex, especially the dorsal anterior cingulate cortex (ACC), has long been implicated in cognitive control and error processing. Although the association between ACC and behavior has been established, it is less clear how ACC contributes to dysfunctional behavior such as substance dependence. Evidence from neuroimaging studies investigating ACC function in substance users is mixed, with some studies showing disengagement of ACC in substance dependent individuals (SDs), while others show increased ACC activity related to substance use. In this study, we investigate ACC function in SDs and healthy individuals performing a change signal task for monetary rewards. Using a priori predictions derived from a recent computational model of ACC, we find that ACC activity differs between SDs and controls in factors related to reward salience and risk aversion between SDs and healthy individuals. Quantitative fits of a computational model to fMRI data reveal significant differences in best fit parameters for reward salience and risk preferences. Specifically, the ACC in SDs shows greater risk aversion, defined as concavity in the utility function, and greater attention to rewards relative to reward omission. Furthermore, across participants risk aversion and reward salience are positively correlated. The results clarify the role that ACC plays in both the reduced sensitivity to omitted rewards and greater reward valuation in SDs. Clinical implications of applying computational modeling in psychiatry are also discussed. PMID:26106528

  10. Long-Term Effects of Musical Training and Functional Plasticity in Salience System

    PubMed Central

    Tu, Shipeng; Peng, Yueheng; Gao, Shan; Li, Jianfu; Dong, Li; Li, Gujing; Lai, Yongxiu; Li, Hong; Yao, Dezhong

    2014-01-01

    Musicians undergoing long-term musical training show improved emotional and cognitive function, which suggests the presence of neuroplasticity. The structural and functional impacts of the human brain have been observed in musicians. In this study, we used data-driven functional connectivity analysis to map local and distant functional connectivity in resting-state functional magnetic resonance imaging data from 28 professional musicians and 28 nonmusicians. Compared with nonmusicians, musicians exhibited significantly greater local functional connectivity density in 10 regions, including the bilateral dorsal anterior cingulate cortex, anterior insula, and anterior temporoparietal junction. A distant functional connectivity analysis demonstrated that most of these regions were included in salience system, which is associated with high-level cognitive control and fundamental attentional process. Additionally, musicians had significantly greater functional integration in this system, especially for connections to the left insula. Increased functional connectivity between the left insula and right temporoparietal junction may be a response to long-term musical training. Our findings indicate that the improvement of salience network is involved in musical training. The salience system may represent a new avenue for exploration regarding the underlying foundations of enhanced higher-level cognitive processes in musicians. PMID:25478236

  11. Combining segmentation and attention: a new foveal attention model

    PubMed Central

    Marfil, Rebeca; Palomino, Antonio J.; Bandera, Antonio

    2014-01-01

    Artificial vision systems cannot process all the information that they receive from the world in real time because it is highly expensive and inefficient in terms of computational cost. Inspired by biological perception systems, artificial attention models pursuit to select only the relevant part of the scene. On human vision, it is also well established that these units of attention are not merely spatial but closely related to perceptual objects (proto-objects). This implies a strong bidirectional relationship between segmentation and attention processes. While the segmentation process is the responsible to extract the proto-objects from the scene, attention can guide segmentation, arising the concept of foveal attention. When the focus of attention is deployed from one visual unit to another, the rest of the scene is perceived but at a lower resolution that the focused object. The result is a multi-resolution visual perception in which the fovea, a dimple on the central retina, provides the highest resolution vision. In this paper, a bottom-up foveal attention model is presented. In this model the input image is a foveal image represented using a Cartesian Foveal Geometry (CFG), which encodes the field of view of the sensor as a fovea (placed in the focus of attention) surrounded by a set of concentric rings with decreasing resolution. Then multi-resolution perceptual segmentation is performed by building a foveal polygon using the Bounded Irregular Pyramid (BIP). Bottom-up attention is enclosed in the same structure, allowing to set the fovea over the most salient image proto-object. Saliency is computed as a linear combination of multiple low level features such as color and intensity contrast, symmetry, orientation and roundness. Obtained results from natural images show that the performance of the combination of hierarchical foveal segmentation and saliency estimation is good in terms of accuracy and speed. PMID:25177289

  12. Primary Visual Cortex as a Saliency Map: A Parameter-Free Prediction and Its Test by Behavioral Data

    PubMed Central

    Zhaoping, Li; Zhe, Li

    2015-01-01

    It has been hypothesized that neural activities in the primary visual cortex (V1) represent a saliency map of the visual field to exogenously guide attention. This hypothesis has so far provided only qualitative predictions and their confirmations. We report this hypothesis’ first quantitative prediction, derived without free parameters, and its confirmation by human behavioral data. The hypothesis provides a direct link between V1 neural responses to a visual location and the saliency of that location to guide attention exogenously. In a visual input containing many bars, one of them saliently different from all the other bars which are identical to each other, saliency at the singleton’s location can be measured by the shortness of the reaction time in a visual search for singletons. The hypothesis predicts quantitatively the whole distribution of the reaction times to find a singleton unique in color, orientation, and motion direction from the reaction times to find other types of singletons. The prediction matches human reaction time data. A requirement for this successful prediction is a data-motivated assumption that V1 lacks neurons tuned simultaneously to color, orientation, and motion direction of visual inputs. Since evidence suggests that extrastriate cortices do have such neurons, we discuss the possibility that the extrastriate cortices play no role in guiding exogenous attention so that they can be devoted to other functions like visual decoding and endogenous attention. PMID:26441341

  13. Primary Visual Cortex as a Saliency Map: A Parameter-Free Prediction and Its Test by Behavioral Data.

    PubMed

    Zhaoping, Li; Zhe, Li

    2015-10-01

    It has been hypothesized that neural activities in the primary visual cortex (V1) represent a saliency map of the visual field to exogenously guide attention. This hypothesis has so far provided only qualitative predictions and their confirmations. We report this hypothesis' first quantitative prediction, derived without free parameters, and its confirmation by human behavioral data. The hypothesis provides a direct link between V1 neural responses to a visual location and the saliency of that location to guide attention exogenously. In a visual input containing many bars, one of them saliently different from all the other bars which are identical to each other, saliency at the singleton's location can be measured by the shortness of the reaction time in a visual search for singletons. The hypothesis predicts quantitatively the whole distribution of the reaction times to find a singleton unique in color, orientation, and motion direction from the reaction times to find other types of singletons. The prediction matches human reaction time data. A requirement for this successful prediction is a data-motivated assumption that V1 lacks neurons tuned simultaneously to color, orientation, and motion direction of visual inputs. Since evidence suggests that extrastriate cortices do have such neurons, we discuss the possibility that the extrastriate cortices play no role in guiding exogenous attention so that they can be devoted to other functions like visual decoding and endogenous attention. PMID:26441341

  14. Quantitative analysis of human-model agreement in visual saliency modeling: a comparative study.

    PubMed

    Borji, Ali; Sihite, Dicky N; Itti, Laurent

    2013-01-01

    Visual attention is a process that enables biological and machine vision systems to select the most relevant regions from a scene. Relevance is determined by two components: 1) top-down factors driven by task and 2) bottom-up factors that highlight image regions that are different from their surroundings. The latter are often referred to as "visual saliency." Modeling bottom-up visual saliency has been the subject of numerous research efforts during the past 20 years, with many successful applications in computer vision and robotics. Available models have been tested with different datasets (e.g., synthetic psychological search arrays, natural images or videos) using different evaluation scores (e.g., search slopes, comparison to human eye tracking) and parameter settings. This has made direct comparison of models difficult. Here, we perform an exhaustive comparison of 35 state-of-the-art saliency models over 54 challenging synthetic patterns, three natural image datasets, and two video datasets, using three evaluation scores. We find that although model rankings vary, some models consistently perform better. Analysis of datasets reveals that existing datasets are highly center-biased, which influences some of the evaluation scores. Computational complexity analysis shows that some models are very fast, yet yield competitive eye movement prediction accuracy. Different models often have common easy/difficult stimuli. Furthermore, several concerns in visual saliency modeling, eye movement datasets, and evaluation scores are discussed and insights for future work are provided. Our study allows one to assess the state-of-the-art, helps to organizing this rapidly growing field, and sets a unified comparison framework for gauging future efforts, similar to the PASCAL VOC challenge in the object recognition and detection domains. PMID:22868572

  15. How saliency, faces, and sound influence gaze in dynamic social scenes.

    PubMed

    Coutrot, Antoine; Guyader, Nathalie

    2014-01-01

    Conversation scenes are a typical example in which classical models of visual attention dramatically fail to predict eye positions. Indeed, these models rarely consider faces as particular gaze attractors and never take into account the important auditory information that always accompanies dynamic social scenes. We recorded the eye movements of participants viewing dynamic conversations taking place in various contexts. Conversations were seen either with their original soundtracks or with unrelated soundtracks (unrelated speech and abrupt or continuous natural sounds). First, we analyze how auditory conditions influence the eye movement parameters of participants. Then, we model the probability distribution of eye positions across each video frame with a statistical method (Expectation-Maximization), allowing the relative contribution of different visual features such as static low-level visual saliency (based on luminance contrast), dynamic low level visual saliency (based on motion amplitude), faces, and center bias to be quantified. Through experimental and modeling results, we show that regardless of the auditory condition, participants look more at faces, and especially at talking faces. Hearing the original soundtrack makes participants follow the speech turn-taking more closely. However, we do not find any difference between the different types of unrelated soundtracks. These eyetracking results are confirmed by our model that shows that faces, and particularly talking faces, are the features that best explain the gazes recorded, especially in the original soundtrack condition. Low-level saliency is not a relevant feature to explain eye positions made on social scenes, even dynamic ones. Finally, we propose groundwork for an audiovisual saliency model. PMID:24993019

  16. Measuring saliency in images: which experimental parameters for the assessment of image quality?

    NASA Astrophysics Data System (ADS)

    Fredembach, Clement; Woolfe, Geoff; Wang, Jue

    2012-01-01

    Predicting which areas of an image are perceptually salient or attended to has become an essential pre-requisite of many computer vision applications. Because observers are notoriously unreliable in remembering where they look a posteriori, and because asking where they look while observing the image necessarily in uences the results, ground truth about saliency and visual attention has to be obtained by gaze tracking methods. From the early work of Buswell and Yarbus to the most recent forays in computer vision there has been, perhaps unfortunately, little agreement on standardisation of eye tracking protocols for measuring visual attention. As the number of parameters involved in experimental methodology can be large, their individual in uence on the nal results is not well understood. Consequently, the performance of saliency algorithms, when assessed by correlation techniques, varies greatly across the literature. In this paper, we concern ourselves with the problem of image quality. Specically: where people look when judging images. We show that in this case, the performance gap between existing saliency prediction algorithms and experimental results is signicantly larger than otherwise reported. To understand this discrepancy, we rst devise an experimental protocol that is adapted to the task of measuring image quality. In a second step, we compare our experimental parameters with the ones of existing methods and show that a lot of the variability can directly be ascribed to these dierences in experimental methodology and choice of variables. In particular, the choice of a task, e.g., judging image quality vs. free viewing, has a great impact on measured saliency maps, suggesting that even for a mildly cognitive task, ground truth obtained by free viewing does not adapt well. Careful analysis of the prior art also reveals that systematic bias can occur depending on instrumental calibration and the choice of test images. We conclude this work by proposing a

  17. Prefrontal/accumbal catecholamine system processes high motivational salience

    PubMed Central

    Puglisi-Allegra, Stefano; Ventura, Rossella

    2012-01-01

    Motivational salience regulates the strength of goal seeking, the amount of risk taken, and the energy invested from mild to extreme. Highly motivational experiences promote highly persistent memories. Although this phenomenon is adaptive in normal conditions, experiences with extremely high levels of motivational salience can promote development of memories that can be re-experienced intrusively for long time resulting in maladaptive outcomes. Neural mechanisms mediating motivational salience attribution are, therefore, very important for individual and species survival and for well-being. However, these neural mechanisms could be implicated in attribution of abnormal motivational salience to different stimuli leading to maladaptive compulsive seeking or avoidance. We have offered the first evidence that prefrontal cortical norepinephrine (NE) transmission is a necessary condition for motivational salience attribution to highly salient stimuli, through modulation of dopamine (DA) in the nucleus accumbens (NAc), a brain area involved in all motivated behaviors. Moreover, we have shown that prefrontal-accumbal catecholamine (CA) system determines approach or avoidance responses to both reward- and aversion-related stimuli only when the salience of the unconditioned stimulus (UCS) is high enough to induce sustained CA activation, thus affirming that this system processes motivational salience attribution selectively to highly salient events. PMID:22754514

  18. Event-Related Fmri Evidence of Frontotemporal Involvement in Aberrant Response Inhibition and Task Switching in Attention-Deficit/hyperactivity Disorder.

    ERIC Educational Resources Information Center

    Tamm, Leanne; Menon, Vinod; Ringel, Jessica; Reiss, Allan L.

    2004-01-01

    Objective: Response inhibition deficits are characteristic of individuals with attention-deficit/hyperactivity disorder (ADHD). Previous functional magnetic resonance imaging (fMRI) studies investigating the neural correlates of this dysfunction have used block designs, making it difficult to disentangle activation differences specifically related…

  19. Human striatal responses to monetary reward depend on saliency.

    PubMed

    Zink, Caroline F; Pagnoni, Giuseppe; Martin-Skurski, Megan E; Chappelow, Jonathan C; Berns, Gregory S

    2004-05-13

    While the striatum has been implicated in reward processing, an alternative view contends that the striatum processes salient events in general. Using fMRI, we investigated human striatal responses to monetary reward while modulating the saliency surrounding its receipt. Money was maximally salient when its receipt depended on a correct response (active) and minimally salient when its receipt was completely independent of the task (passive). The saliency manipulation was confirmed by skin conductance responses and subjective ratings of the stimuli. Significant caudate and nucleus accumbens activations occurred following the active compared to passive money. Such activations were attributed to saliency rather than the motor requirement associated with the active money because striatal activations were not observed when the money was replaced by inconsequential, nonrewarding stimuli. The present study provides evidence that the striatum's role in reward processing is dependent on the saliency associated with reward, rather than value or hedonic feelings. PMID:15134646

  20. Diversification of visual media retrieval results using saliency detection

    NASA Astrophysics Data System (ADS)

    Muratov, Oleg; Boato, Giulia; De Natale, Franesco G. B.

    2013-03-01

    Diversification of retrieval results allows for better and faster search. Recently there has been proposed different methods for diversification of image retrieval results mainly utilizing text information and techniques imported from natural language processing domain. However, images contain visual information that is impossible to describe in text and the use of visual features is inevitable. Visual saliency is information about the main object of an image implicitly included by humans while creating visual content. For this reason it is naturally to exploit this information for the task of diversification of the content. In this work we study whether visual saliency can be used for the task of diversification and propose a method for re-ranking image retrieval results using saliency. The evaluation has shown that the use of saliency information results in higher diversity of retrieval results.

  1. A ventral salience network in the macaque brain.

    PubMed

    Touroutoglou, Alexandra; Bliss-Moreau, Eliza; Zhang, Jiahe; Mantini, Dante; Vanduffel, Wim; Dickerson, Bradford C; Barrett, Lisa Feldman

    2016-05-15

    Successful navigation of the environment requires attending and responding efficiently to objects and conspecifics with the potential to benefit or harm (i.e., that have value). In humans, this function is subserved by a distributed large-scale neural network called the "salience network". We have recently demonstrated that there are two anatomically and functionally dissociable salience networks anchored in the dorsal and ventral portions of the human anterior insula (Touroutoglou et al., 2012). In this paper, we test the hypothesis that these two subnetworks exist in rhesus macaques (Macaca mulatta). We provide evidence that a homologous ventral salience network exists in macaques, but that the connectivity of the dorsal anterior insula in macaques is not sufficiently developed as a dorsal salience network. The evolutionary implications of these finding are considered. PMID:26899785

  2. Motion saliency detection using a temporal fourier transform

    NASA Astrophysics Data System (ADS)

    Chen, Zhe; Wang, Xin; Sun, Zhen; Wang, Zhijian

    2016-06-01

    Motion saliency detection aims at detecting the dynamic semantic regions in a video sequence. It is very important for many vision tasks. This paper proposes a new type of motion saliency detection method, Temporal Fourier Transform, for fast motion saliency detection. Different from conventional motion saliency detection methods that use complex mathematical models or features, variations in the phase spectrum of consecutive frames are identified and extracted as the key to obtaining the location of salient motion. As all the calculation is made on the temporal frequency spectrum, our model is independent of features, background models, or other forms of prior knowledge about scenes. The benefits of the proposed approach are evaluated for various videos where the number of moving objects, illumination, and background are all different. Compared with some the state of the art methods, our method achieves both good accuracy and fast computation.

  3. Salience measure for assessing scale-based features in mammograms.

    PubMed

    Perconti, Philip; Loew, Murray H

    2007-12-01

    This work assesses the usefulness of an objective, task-based image quality measure that is correlated with perceived image quality; the measure uses the most salient features contained within a medical image. Contributions include the development of a perceptually correlated metric that is useful for quantifying the salience of local, low-level visual cues and identifying those spatial frequencies that are most distinct and perhaps most relied upon by radiologists for decision making. A set of 40 mammograms and registered eye position data from nine observers was used to evaluate the salience metric. A parsimonious analysis-of-variance model explained the variance in the salience results. This analysis is generalized to a population of readers and cases. An analysis of salience versus time of first eye fixation shows good correlation with true positive lesions that were found by experienced readers in less than 2 s. PMID:18059917

  4. Effects of signal salience and noise on performance and stress in an abbreviated vigil

    NASA Astrophysics Data System (ADS)

    Helton, William Stokely

    Vigilance or sustained attention tasks traditionally require observers to detect predetermined signals that occur unpredictably over periods of 30 min to several hours (Warm, 1984). These tasks are taxing and have been useful in revealing the effects of stress agents, such as infectious disease and drugs, on human performance (Alluisi, 1969; Damos & Parker, 1994; Warm, 1993). However, their long duration has been an inconvenience. Recently, Temple and his associates (Temple et al., 2000) developed an abbreviated 12-min vigilance task that duplicates many of the findings with longer duration vigils. The present study was designed to explore further the similarity of the abbreviated task to long-duration vigils by investigating the effects of signal salience and jet-aircraft engine noise on performance, operator stress, and coping strategies. Forty-eight observers (24 males and 24 females) were assigned at random to each of four conditions resulting from the factorial combination of signal salience (high and low contrast signals) and background noise (quiet and jet-aircraft noise). As is the case with long-duration vigils (Warm, 1993), signal detection in the abbreviated task was poorer for low salience than for high salience signals. In addition, stress scores, as indexed by the Dundee Stress State Questionnaire (Matthews, Joiner, Gilliland, Campbell, & Falconer, 1999), were elevated in the low as compared to the high salience condition. Unlike longer vigils, however, (Becker, Warm, Dember, & Hancock, 1996), signal detection in the abbreviated task was superior in the presence of aircraft noise than in quiet. Noise also attenuated the stress of the vigil, a result that is counter to previous findings regarding the effects of noise in a variety of other scenarios (Clark, 1984). Examination of observers' coping responses, as assessed by the Coping Inventory for Task Situations (Matthews & Campbell, 1998), indicated that problem-focused coping was the overwhelming

  5. Multi-scale saliency search in image analysis.

    SciTech Connect

    Slepoy, Alexander; Campisi, Anthony; Backer, Alejandro

    2005-10-01

    Saliency detection in images is an important outstanding problem both in machine vision design and the understanding of human vision mechanisms. Recently, seminal work by Itti and Koch resulted in an effective saliency-detection algorithm. We reproduce the original algorithm in a software application Vision and explore its limitations. We propose extensions to the algorithm that promise to improve performance in the case of difficult-to-detect objects.

  6. Disgust sensitivity predicts defensive responding to mortality salience.

    PubMed

    Kelley, Nicholas J; Crowell, Adrienne L; Tang, David; Harmon-Jones, Eddie; Schmeichel, Brandon J

    2015-10-01

    Disgust protects the physical self. The present authors suggest that disgust also contributes to the protection of the psychological self by fostering stronger defensive reactions to existential concerns. To test this idea, 3 studies examined the link between disgust sensitivity and defensive responses to mortality salience or "terror management" processes (Greenberg, Solomon, & Pyszczynski, 1997). Each study included an individual difference measure of disgust sensitivity, a manipulation of mortality salience, and a dependent measure of defensive responding. In Study 1, disgust sensitivity predicted increases in worldview defense in the mortality salience condition but not in the control condition. In Study 2, disgust sensitivity predicted increases in optimistic perceptions of the future in the mortality salience condition but not in the control condition. In Study 3, disgust sensitivity predicted reductions in delay discounting for those in the mortality salience condition such that those higher in disgust sensitivity discounted the future less. This pattern did not occur in the control condition. These findings highlight disgust sensitivity as a key to understanding reactions to mortality salience, and they support the view that disgust-related responses protect against both physical (e.g., noxious substances) and psychological threats. PMID:25775230

  7. Removing label ambiguity in learning-based visual saliency estimation.

    PubMed

    Li, Jia; Xu, Dong; Gao, Wen

    2012-04-01

    Visual saliency is a useful clue to depict visually important image/video contents in many multimedia applications. In visual saliency estimation, a feasible solution is to learn a "feature-saliency" mapping model from the user data obtained by manually labeling activities or eye-tracking devices. However, label ambiguities may also arise due to the inaccurate and inadequate user data. To process the noisy training data, we propose a multi-instance learning to rank approach for visual saliency estimation. In our approach, the correlations between various image patches are incorporated into an ordinal regression framework. By iteratively refining a ranking model and relabeling the image patches with respect to their mutual correlations, the label ambiguities can be effectively removed from the training data. Consequently, visual saliency can be effectively estimated by the ranking model, which can pop out real targets and suppress real distractors. Extensive experiments on two public image data sets show that our approach outperforms 11 state-of-the-art methods remarkably in visual saliency estimation. PMID:22180509

  8. Spectral saliency via automatic adaptive amplitude spectrum analysis

    NASA Astrophysics Data System (ADS)

    Wang, Xiaodong; Dai, Jialun; Zhu, Yafei; Zheng, Haiyong; Qiao, Xiaoyan

    2016-03-01

    Suppressing nonsalient patterns by smoothing the amplitude spectrum at an appropriate scale has been shown to effectively detect the visual saliency in the frequency domain. Different filter scales are required for different types of salient objects. We observe that the optimal scale for smoothing amplitude spectrum shares a specific relation with the size of the salient region. Based on this observation and the bottom-up saliency detection characterized by spectrum scale-space analysis for natural images, we propose to detect visual saliency, especially with salient objects of different sizes and locations via automatic adaptive amplitude spectrum analysis. We not only provide a new criterion for automatic optimal scale selection but also reserve the saliency maps corresponding to different salient objects with meaningful saliency information by adaptive weighted combination. The performance of quantitative and qualitative comparisons is evaluated by three different kinds of metrics on the four most widely used datasets and one up-to-date large-scale dataset. The experimental results validate that our method outperforms the existing state-of-the-art saliency models for predicting human eye fixations in terms of accuracy and robustness.

  9. Airport detection in remote sensing images: a method based on saliency map.

    PubMed

    Wang, Xin; Lv, Qi; Wang, Bin; Zhang, Liming

    2013-04-01

    The detection of airport attracts lots of attention and becomes a hot topic recently because of its applications and importance in military and civil aviation fields. However, the complicated background around airports brings much difficulty into the detection. This paper presents a new method for airport detection in remote sensing images. Distinct from other methods which analyze images pixel by pixel, we introduce visual attention mechanism into detection of airport and improve the efficiency of detection greatly. Firstly, Hough transform is used to judge whether an airport exists in an image. Then an improved graph-based visual saliency model is applied to compute the saliency map and extract regions of interest (ROIs). The airport target is finally detected according to the scale-invariant feature transform features which are extracted from each ROI and classified by hierarchical discriminant regression tree. Experimental results show that the proposed method is faster and more accurate than existing methods, and has lower false alarm rate and better anti-noise performance simultaneously. PMID:24427198

  10. Saliency-aware food image segmentation for personal dietary assessment using a wearable computer

    NASA Astrophysics Data System (ADS)

    Chen, Hsin-Chen; Jia, Wenyan; Sun, Xin; Li, Zhaoxin; Li, Yuecheng; Fernstrom, John D.; Burke, Lora E.; Baranowski, Thomas; Sun, Mingui

    2015-02-01

    Image-based dietary assessment has recently received much attention in the community of obesity research. In this assessment, foods in digital pictures are specified, and their portion sizes (volumes) are estimated. Although manual processing is currently the most utilized method, image processing holds much promise since it may eventually lead to automatic dietary assessment. In this paper we study the problem of segmenting food objects from images. This segmentation is difficult because of various food types, shapes and colors, different decorating patterns on food containers, and occlusions of food and non-food objects. We propose a novel method based on a saliency-aware active contour model (ACM) for automatic food segmentation from images acquired by a wearable camera. An integrated saliency estimation approach based on food location priors and visual attention features is designed to produce a salient map of possible food regions in the input image. Next, a geometric contour primitive is generated and fitted to the salient map by means of multi-resolution optimization with respect to a set of affine and elastic transformation parameters. The food regions are then extracted after contour fitting. Our experiments using 60 food images showed that the proposed method achieved significantly higher accuracy in food segmentation when compared to conventional segmentation methods.

  11. Dopamine, urges to smoke, and the relative salience of drug versus non-drug reward

    PubMed Central

    Das, Ravi K.; Kamboj, Sunjeev K.; Curran, H. Valerie

    2015-01-01

    When addicted individuals are exposed to drug-related stimuli, dopamine release is thought to mediate incentive salience attribution, increasing attentional bias, craving and drug seeking. It is unclear whether dopamine acts specifically on drug cues versus other rewards, and if these effects correspond with craving and other forms of cognitive bias. Here, we administered the dopamine D2/D3 agonist pramipexole (0.5 mg) to 16 tobacco smokers in a double-blind placebo-controlled crossover design. Visual fixations on smoking and money images were recorded alongside smoking urges and fluency tasks. Pramipexole attenuated a marked bias in initial orienting towards smoking relative to money but did not alter a maintained attentional bias towards smoking. Pramipexole decreased urges to smoke retrospectively after the task but not on a state scale. Fewer smoking words were generated after pramipexole but phonological and semantic fluency were preserved. Although these treatment effects did not correlate with each other, changes in initial orienting towards smoking and money were inversely related to baseline scores. In conclusion, pramipexole can reduce the salience of an addictive drug compared with other rewards and elicit corresponding changes in smoking urges and cognitive bias. These reward-specific and baseline-dependent effects support an ‘inverted-U’ shaped profile of dopamine in addiction. PMID:24526184

  12. Dopamine, urges to smoke, and the relative salience of drug versus non-drug reward.

    PubMed

    Freeman, Tom P; Das, Ravi K; Kamboj, Sunjeev K; Curran, H Valerie

    2015-01-01

    When addicted individuals are exposed to drug-related stimuli, dopamine release is thought to mediate incentive salience attribution, increasing attentional bias, craving and drug seeking. It is unclear whether dopamine acts specifically on drug cues versus other rewards, and if these effects correspond with craving and other forms of cognitive bias. Here, we administered the dopamine D2/D3 agonist pramipexole (0.5 mg) to 16 tobacco smokers in a double-blind placebo-controlled crossover design. Visual fixations on smoking and money images were recorded alongside smoking urges and fluency tasks. Pramipexole attenuated a marked bias in initial orienting towards smoking relative to money but did not alter a maintained attentional bias towards smoking. Pramipexole decreased urges to smoke retrospectively after the task but not on a state scale. Fewer smoking words were generated after pramipexole but phonological and semantic fluency were preserved. Although these treatment effects did not correlate with each other, changes in initial orienting towards smoking and money were inversely related to baseline scores. In conclusion, pramipexole can reduce the salience of an addictive drug compared with other rewards and elicit corresponding changes in smoking urges and cognitive bias. These reward-specific and baseline-dependent effects support an 'inverted-U' shaped profile of dopamine in addiction. PMID:24526184

  13. On the Electrophysiological Evidence for the Capture of Visual Attention

    ERIC Educational Resources Information Center

    McDonald, John J.; Green, Jessica J.; Jannati, Ali; Di Lollo, Vincent

    2013-01-01

    The presence of a salient distractor interferes with visual search. According to the salience-driven selection hypothesis, this interference is because of an initial deployment of attention to the distractor. Three event-related potential (ERP) findings have been regarded as evidence for this hypothesis: (a) salient distractors were found to…

  14. A value-driven mechanism of attentional selection

    PubMed Central

    Anderson, Brian A.

    2013-01-01

    Attention selects stimuli for cognitive processing, and the mechanisms that underlie the process of attentional selection have been a major topic of psychological research for over 30 years. From this research, it has been well documented that attentional selection can proceed both voluntarily, driven by visual search goals, and involuntarily, driven by the physical salience of stimuli. In this review, I provide a conceptual framework for attentional control that emphasizes the need for stimulus selection to promote the survival and wellbeing of an organism. I argue that although goal-driven and salience-driven mechanisms of attentional selection fit within this framework, a central component that is missing is a mechanism of attentional selection that is uniquely driven by learned associations between stimuli and rewards. I go on to review recent evidence for such a value-driven mechanism of attentional selection, and describe how this mechanism functions independently of the well-documented salience-driven and goal-driven mechanisms. I conclude by arguing that reward learning modifies the attentional priority of stimuli, allowing them to compete more effectively for selection even when nonsalient and task-irrelevant. PMID:23589803

  15. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience

    PubMed Central

    Gong, Diankun; He, Hui; Ma, Weiyi; Liu, Dongbo; Huang, Mengting; Dong, Li; Gong, Jinnan; Li, Jianfu; Yao, Dezhong

    2016-01-01

    Action video games (AVGs) have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN) and Central Executive Network (CEN), which are responsible for attention and working memory, respectively, two cognitive functions essential for AVG playing. This study initiated a systematic investigation of this proposition by analyzing AVG experts' and amateurs' resting-state brain functions through graph theoretical analyses and functional connectivity. Results reveal enhanced intra- and internetwork functional integrations in AVG experts compared to amateurs. The findings support the possible relation between AVG experience and the neural network plasticity. PMID:26885408

  16. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience.

    PubMed

    Gong, Diankun; He, Hui; Ma, Weiyi; Liu, Dongbo; Huang, Mengting; Dong, Li; Gong, Jinnan; Li, Jianfu; Luo, Cheng; Yao, Dezhong

    2016-01-01

    Action video games (AVGs) have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN) and Central Executive Network (CEN), which are responsible for attention and working memory, respectively, two cognitive functions essential for AVG playing. This study initiated a systematic investigation of this proposition by analyzing AVG experts' and amateurs' resting-state brain functions through graph theoretical analyses and functional connectivity. Results reveal enhanced intra- and internetwork functional integrations in AVG experts compared to amateurs. The findings support the possible relation between AVG experience and the neural network plasticity. PMID:26885408

  17. The importance of integration and top-down salience when listening to complex multi-part musical stimuli.

    PubMed

    Uhlig, Marie; Fairhurst, Merle T; Keller, Peter E

    2013-08-15

    In listening to multi-part music, auditory streams can be attended to either selectively or globally. More specifically, musicians rely on prioritized integrative attention which incorporates both stream segregation and integration to assess the relationship between concurrent parts. In this fMRI study, we used a piano duet to investigate which factors of a leader-follower relationship between parts grab the listener's attention and influence the perception of multi-part music. The factors considered included the structural relationship between melody and accompaniment as well as the temporal relationship (asynchronies) between parts. The structural relationship was manipulated by cueing subjects to the part of the duet that had to be prioritized. The temporal relationship was investigated by synthetically shifting the onset times of melody and accompaniment to either a consistent melody or accompaniment lead. The relative importance of these relationship factors for segregation and integration as attentional mechanisms was of interest. Participants were required to listen to the cued part and then globally assess if the prioritized stream was leading or following compared to the second stream. Results show that the melody is judged as more leading when it is globally temporally ahead whereas the accompaniment is not judged as leading when it is ahead. This bias may be a result of the interaction of salience of both leader-follower relationship factors. Interestingly, the corresponding interaction effect in the fMRI-data yields an inverse bias for melody in a fronto-parietal attention network. Corresponding parameter estimates within the dlPFC and right IPS show higher neural activity for attending to melody when listening to a performance without a temporal leader, pointing to an interaction of salience of both factors in listening to music. Both frontal and parietal activation implicate segregation and integration mechanisms and a top-down influence of salience

  18. Distinct neuronal populations in the basal forebrain encode motivational salience and movement

    PubMed Central

    Avila, Irene; Lin, Shih-Chieh

    2014-01-01

    Basal forebrain (BF) is one of the largest cortically-projecting neuromodulatory systems in the mammalian brain, and plays a key role in attention, arousal, learning and memory. The cortically projecting BF neurons, comprised of mainly magnocellular cholinergic and GABAergic neurons, are widely distributed across several brain regions that spatially overlap with the ventral striatopallidal system at the ventral pallidum (VP). As a first step toward untangling the respective functions of spatially overlapping BF and VP systems, the goal of this study was to comprehensively characterize the behavioral correlates and physiological properties of heterogeneous neuronal populations in the BF region. We found that, while rats performed a reward-biased simple reaction time task, distinct neuronal populations encode either motivational salience or movement information. The motivational salience of attended stimuli is encoded by phasic bursting activity of a large population of slow-firing neurons that have large, broad, and complex action potential waveforms. In contrast, two other separate groups of neurons encode movement-related information, and respectively increase and decrease firing rates while rats maintained fixation. These two groups of neurons mostly have higher firing rates and small, narrow action potential waveforms. These results support the conclusion that multiple neurophysiologically distinct neuronal populations in the BF region operate independently of each other as parallel functional circuits. These observations also caution against interpreting neuronal activity in this region as a homogeneous population reflecting the function of either BF or VP alone. We suggest that salience- and movement-related neuronal populations likely correspond to BF corticopetal neurons and VP neurons, respectively. PMID:25538586

  19. Landmark Detection in Orbital Images Using Salience Histograms

    NASA Technical Reports Server (NTRS)

    Wagstaff, Kiri L.; Panetta, Julian; Schorghofer, Norbert; Greeley, Ronald; PendletonHoffer, Mary; bunte, Melissa

    2010-01-01

    NASA's planetary missions have collected, and continue to collect, massive volumes of orbital imagery. The volume is such that it is difficult to manually review all of the data and determine its significance. As a result, images are indexed and searchable by location and date but generally not by their content. A new automated method analyzes images and identifies "landmarks," or visually salient features such as gullies, craters, dust devil tracks, and the like. This technique uses a statistical measure of salience derived from information theory, so it is not associated with any specific landmark type. It identifies regions that are unusual or that stand out from their surroundings, so the resulting landmarks are context-sensitive areas that can be used to recognize the same area when it is encountered again. A machine learning classifier is used to identify the type of each discovered landmark. Using a specified window size, an intensity histogram is computed for each such window within the larger image (sliding the window across the image). Next, a salience map is computed that specifies, for each pixel, the salience of the window centered at that pixel. The salience map is thresholded to identify landmark contours (polygons) using the upper quartile of salience values. Descriptive attributes are extracted for each landmark polygon: size, perimeter, mean intensity, standard deviation of intensity, and shape features derived from an ellipse fit.

  20. Learning a Combined Model of Visual Saliency for Fixation Prediction.

    PubMed

    Wang, Jingwei; Borji, Ali; Jay Kuo, C-C; Itti, Laurent

    2016-04-01

    A large number of saliency models, each based on a different hypothesis, have been proposed over the past 20 years. In practice, while subscribing to one hypothesis or computational principle makes a model that performs well on some types of images, it hinders the general performance of a model on arbitrary images and large-scale data sets. One natural approach to improve overall saliency detection accuracy would then be fusing different types of models. In this paper, inspired by the success of late-fusion strategies in semantic analysis and multi-modal biometrics, we propose to fuse the state-of-the-art saliency models at the score level in a para-boosting learning fashion. First, saliency maps generated by several models are used as confidence scores. Then, these scores are fed into our para-boosting learner (i.e., support vector machine, adaptive boosting, or probability density estimator) to generate the final saliency map. In order to explore the strength of para-boosting learners, traditional transformation-based fusion strategies, such as Sum, Min, and Max, are also explored and compared in this paper. To further reduce the computation cost of fusing too many models, only a few of them are considered in the next step. Experimental results show that score-level fusion outperforms each individual model and can further reduce the performance gap between the current models and the human inter-observer model. PMID:26829792

  1. Visual saliency in MPEG-4 AVC video stream

    NASA Astrophysics Data System (ADS)

    Ammar, M.; Mitrea, M.; Hasnaoui, M.; Le Callet, P.

    2015-03-01

    Visual saliency maps already proved their efficiency in a large variety of image/video communication application fields, covering from selective compression and channel coding to watermarking. Such saliency maps are generally based on different visual characteristics (like color, intensity, orientation, motion,…) computed from the pixel representation of the visual content. This paper resumes and extends our previous work devoted to the definition of a saliency map solely extracted from the MPEG-4 AVC stream syntax elements. The MPEG-4 AVC saliency map thus defined is a fusion of static and dynamic map. The static saliency map is in its turn a combination of intensity, color and orientation features maps. Despite the particular way in which all these elementary maps are computed, the fusion techniques allowing their combination plays a critical role in the final result and makes the object of the proposed study. A total of 48 fusion formulas (6 for combining static features and, for each of them, 8 to combine static to dynamic features) are investigated. The performances of the obtained maps are evaluated on a public database organized at IRCCyN, by computing two objective metrics: the Kullback-Leibler divergence and the area under curve.

  2. Visual Saliency Prediction and Evaluation across Different Perceptual Tasks

    PubMed Central

    Rahman, Shafin; Bruce, Neil

    2015-01-01

    Saliency maps produced by different algorithms are often evaluated by comparing output to fixated image locations appearing in human eye tracking data. There are challenges in evaluation based on fixation data due to bias in the data. Properties of eye movement patterns that are independent of image content may limit the validity of evaluation results, including spatial bias in fixation data. To address this problem, we present modeling and evaluation results for data derived from different perceptual tasks related to the concept of saliency. We also present a novel approach to benchmarking to deal with some of the challenges posed by spatial bias. The results presented establish the value of alternatives to fixation data to drive improvement and development of models. We also demonstrate an approach to approximate the output of alternative perceptual tasks based on computational saliency and/or eye gaze data. As a whole, this work presents novel benchmarking results and methods, establishes a new performance baseline for perceptual tasks that provide an alternative window into visual saliency, and demonstrates the capacity for saliency to serve in approximating human behaviour for one visual task given data from another. PMID:26368124

  3. Multisensory attention training for treatment of tinnitus

    PubMed Central

    D. P., Spiegel; T., Linford; B., Thompson; M. A., Petoe; K., Kobayashi; C. M., Stinear; G. D., Searchfield

    2015-01-01

    Tinnitus is the conscious perception of sound with no physical sound source. Some models of tinnitus pathophysiology suggest that networks associated with attention, memory, distress and multisensory experience are involved in tinnitus perception. The aim of this study was to evaluate whether a multisensory attention training paradigm which used audio, visual, and somatosensory stimulation would reduce tinnitus. Eighteen participants with predominantly unilateral chronic tinnitus were randomized between two groups receiving 20 daily sessions of either integration (attempting to reduce salience to tinnitus by binding with multisensory stimuli) or attention diversion (multisensory stimuli opposite side to tinnitus) training. The training resulted in small but statistically significant reductions in Tinnitus Functional Index and Tinnitus Severity Numeric Scale scores and improved attentional abilities. No statistically significant improvements in tinnitus were found between the training groups. This study demonstrated that a short period of multisensory attention training reduced unilateral tinnitus, but directing attention toward or away from the tinnitus side did not differentiate this effect. PMID:26020589

  4. Temporal-Spatial Neural Activation Patterns Linked to Perceptual Encoding of Emotional Salience

    PubMed Central

    Todd, Rebecca M.; Taylor, Margot J.; Robertson, Amanda; Cassel, Daniel B.; Doesberg, Sam M.; Lee, Daniel H.; Shek, Pang N.; Pang, Elizabeth W.

    2014-01-01

    It is well known that we continuously filter incoming sensory information, selectively allocating attention to what is important while suppressing distracting or irrelevant information. Yet questions remain about spatiotemporal patterns of neural processes underlying attentional biases toward emotionally significant aspects of the world. One index of affectively biased attention is an emotional variant of an attentional blink (AB) paradigm, which reveals enhanced perceptual encoding for emotionally salient over neutral stimuli under conditions of limited executive attention. The present study took advantage of the high spatial and temporal resolution of magnetoencephalography (MEG) to investigate neural activation related to emotional and neutral targets in an AB task. MEG data were collected while participants performed a rapid stimulus visual presentation task in which two target stimuli were embedded in a stream of distractor words. The first target (T1) was a number and the second (T2) either an emotionally salient or neutral word. Behavioural results replicated previous findings of greater accuracy for emotionally salient than neutral T2 words. MEG source analyses showed that activation in orbitofrontal cortex, characterized by greater power in the theta and alpha bands, and dorsolateral prefrontal activation were associated with successful perceptual encoding of emotionally salient relative to neutral words. These effects were observed between 250 and 550 ms, latencies associated with discrimination of perceived from unperceived stimuli. These data suggest that important nodes of both emotional salience and frontoparietal executive systems are associated with the emotional modulation of the attentional blink. PMID:24727751

  5. Saliency region and density maximization for salient object detection

    NASA Astrophysics Data System (ADS)

    He, Xin; Jing, Huiyun

    2015-03-01

    In this paper, we propose an alternative salient object detection method based on maximum saliency region and density. The proposed approach can automatically detect the salient object with a well-defined boundary. Saliency region and density maximization is used as the quality function to find the optimal window containing a salient object. And for efficiently executing window search, a branch-and-bound search algorithm based on saliency region and density is proposed. Then the located window is used to initialize the GrabCut method, and the salient object with a well- defined boundary is extracted through applying GrabCut. Experimental results show that the proposed salient object detection approach outperforms the state-of-the-art methods.

  6. Land Cover Change Detection Using Saliency Andwavelet Transformation

    NASA Astrophysics Data System (ADS)

    Zhang, Haopeng; Jiang, Zhiguo; Cheng, Yan

    2016-06-01

    How to obtain accurate difference map remains an open challenge in change detection. To tackle this problem, we propose a change detection method based on saliency detection and wavelet transformation. We do frequency-tuned saliency detection in initial difference image (IDI) obtained by logarithm ratio to get a salient difference image (SDI). Then, we calculate local entropy of SDI to obtain an entropic salient difference image (ESDI). The final difference image (FDI) is the wavelet fusion of IDI and ESDI, and Otsu thresholding is used to extract difference map from FDI. Experimental results validate the effectiveness and feasibility.

  7. Art Expertise Reduces Influence of Visual Salience on Fixation in Viewing Abstract-Paintings

    PubMed Central

    Koide, Naoko; Kubo, Takatomi; Nishida, Satoshi; Shibata, Tomohiro; Ikeda, Kazushi

    2015-01-01

    When viewing a painting, artists perceive more information from the painting on the basis of their experience and knowledge than art novices do. This difference can be reflected in eye scan paths during viewing of paintings. Distributions of scan paths of artists are different from those of novices even when the paintings contain no figurative object (i.e. abstract paintings). There are two possible explanations for this difference of scan paths. One is that artists have high sensitivity to high-level features such as textures and composition of colors and therefore their fixations are more driven by such features compared with novices. The other is that fixations of artists are more attracted by salient features than those of novices and the fixations are driven by low-level features. To test these, we measured eye fixations of artists and novices during the free viewing of various abstract paintings and compared the distribution of their fixations for each painting with a topological attentional map that quantifies the conspicuity of low-level features in the painting (i.e. saliency map). We found that the fixation distribution of artists was more distinguishable from the saliency map than that of novices. This difference indicates that fixations of artists are less driven by low-level features than those of novices. Our result suggests that artists may extract visual information from paintings based on high-level features. This ability of artists may be associated with artists’ deep aesthetic appreciation of paintings. PMID:25658327

  8. Art expertise reduces influence of visual salience on fixation in viewing abstract-paintings.

    PubMed

    Koide, Naoko; Kubo, Takatomi; Nishida, Satoshi; Shibata, Tomohiro; Ikeda, Kazushi

    2015-01-01

    When viewing a painting, artists perceive more information from the painting on the basis of their experience and knowledge than art novices do. This difference can be reflected in eye scan paths during viewing of paintings. Distributions of scan paths of artists are different from those of novices even when the paintings contain no figurative object (i.e. abstract paintings). There are two possible explanations for this difference of scan paths. One is that artists have high sensitivity to high-level features such as textures and composition of colors and therefore their fixations are more driven by such features compared with novices. The other is that fixations of artists are more attracted by salient features than those of novices and the fixations are driven by low-level features. To test these, we measured eye fixations of artists and novices during the free viewing of various abstract paintings and compared the distribution of their fixations for each painting with a topological attentional map that quantifies the conspicuity of low-level features in the painting (i.e. saliency map). We found that the fixation distribution of artists was more distinguishable from the saliency map than that of novices. This difference indicates that fixations of artists are less driven by low-level features than those of novices. Our result suggests that artists may extract visual information from paintings based on high-level features. This ability of artists may be associated with artists' deep aesthetic appreciation of paintings. PMID:25658327

  9. VSI: a visual saliency-induced index for perceptual image quality assessment.

    PubMed

    Zhang, Lin; Shen, Ying; Li, Hongyu

    2014-10-01

    Perceptual image quality assessment (IQA) aims to use computational models to measure the image quality in consistent with subjective evaluations. Visual saliency (VS) has been widely studied by psychologists, neurobiologists, and computer scientists during the last decade to investigate, which areas of an image will attract the most attention of the human visual system. Intuitively, VS is closely related to IQA in that suprathreshold distortions can largely affect VS maps of images. With this consideration, we propose a simple but very effective full reference IQA method using VS. In our proposed IQA model, the role of VS is twofold. First, VS is used as a feature when computing the local quality map of the distorted image. Second, when pooling the quality score, VS is employed as a weighting function to reflect the importance of a local region. The proposed IQA index is called visual saliency-based index (VSI). Several prominent computational VS models have been investigated in the context of IQA and the best one is chosen for VSI. Extensive experiments performed on four large-scale benchmark databases demonstrate that the proposed IQA index VSI works better in terms of the prediction accuracy than all state-of-the-art IQA indices we can find while maintaining a moderate computational complexity. The MATLAB source code of VSI and the evaluation results are publicly available online at http://sse.tongji.edu.cn/linzhang/IQA/VSI/VSI.htm. PMID:25122572

  10. Evolution of attention mechanisms for early visual processing

    NASA Astrophysics Data System (ADS)

    Müller, Thomas; Knoll, Alois

    2011-03-01

    Early visual processing as a method to speed up computations on visual input data has long been discussed in the computer vision community. The general target of a such approaches is to filter nonrelevant information from the costly higher-level visual processing algorithms. By insertion of this additional filter layer the overall approach can be speeded up without actually changing the visual processing methodology. Being inspired by the layered architecture of the human visual processing apparatus, several approaches for early visual processing have been recently proposed. Most promising in this field is the extraction of a saliency map to determine regions of current attention in the visual field. Such saliency can be computed in a bottom-up manner, i.e. the theory claims that static regions of attention emerge from a certain color footprint, and dynamic regions of attention emerge from connected blobs of textures moving in a uniform way in the visual field. Top-down saliency effects are either unconscious through inherent mechanisms like inhibition-of-return, i.e. within a period of time the attention level paid to a certain region automatically decreases if the properties of that region do not change, or volitional through cognitive feedback, e.g. if an object moves consistently in the visual field. These bottom-up and top-down saliency effects have been implemented and evaluated in a previous computer vision system for the project JAST. In this paper an extension applying evolutionary processes is proposed. The prior vision system utilized multiple threads to analyze the regions of attention delivered from the early processing mechanism. Here, in addition, multiple saliency units are used to produce these regions of attention. All of these saliency units have different parameter-sets. The idea is to let the population of saliency units create regions of attention, then evaluate the results with cognitive feedback and finally apply the genetic mechanism

  11. Brain Activation of Identity Switching in Multiple Identity Tracking Task

    PubMed Central

    Lyu, Chuang; Hu, Siyuan; Wei, Liuqing; Zhang, Xuemin; Talhelm, Thomas

    2015-01-01

    When different objects switch identities in the multiple identity tracking (MIT) task, viewers need to rebind objects’ identity and location, which requires attention. This rebinding helps people identify the regions targets are in (where they need to focus their attention) and inhibit unimportant regions (where distractors are). This study investigated the processing of attentional tracking after identity switching in an adapted MIT task. This experiment used three identity-switching conditions: a target-switching condition (where the target objects switched identities), a distractor-switching condition (where the distractor objects switched identities), and a no-switching condition. Compared to the distractor-switching condition, the target-switching condition elicited greater activation in the frontal eye fields (FEF), intraparietal sulcus (IPS), and visual cortex. Compared to the no-switching condition, the target-switching condition elicited greater activation in the FEF, inferior frontal gyrus (pars orbitalis) (IFG-Orb), IPS, visual cortex, middle temporal lobule, and anterior cingulate cortex. Finally, the distractor-switching condition showed greater activation in the IFG-Orb compared to the no-switching condition. These results suggest that, in the target-switching condition, the FEF and IPS (the dorsal attention network) might be involved in goal-driven attention to targets during attentional tracking. In addition, in the distractor-switching condition, the activation of the IFG-Orb may indicate salient change that pulls attention away automatically. PMID:26699865

  12. Rapid Acquisition but Slow Extinction of an Attentional Bias in Space

    ERIC Educational Resources Information Center

    Jiang, Yuhong V.; Swallow, Khena M.; Rosenbaum, Gail M.; Herzig, Chelsey

    2013-01-01

    Substantial research has focused on the allocation of spatial attention based on goals or perceptual salience. In everyday life, however, people also direct attention using their previous experience. Here we investigate the pace at which people incidentally learn to prioritize specific locations. Participants searched for a T among Ls in a visual…

  13. Eye Tracking Reveals Impaired Attentional Disengagement Associated with Sensory Response Patterns in Children with Autism

    ERIC Educational Resources Information Center

    Sabatos-DeVito, Maura; Schipul, Sarah E.; Bulluck, John C.; Belger, Aysenil; Baranek, Grace T.

    2016-01-01

    This study used a gap-overlap paradigm to examine the impact of distractor salience and temporal overlap on the ability to disengage and orient attention in 50 children (4-13 years) with ASD, DD and TD, and associations between attention and sensory response patterns. Results revealed impaired disengagement and orienting accuracy in ASD.…

  14. Visual Attention Model Based on Statistical Properties of Neuron Responses

    PubMed Central

    Duan, Haibin; Wang, Xiaohua

    2015-01-01

    Visual attention is a mechanism of the visual system that can select relevant objects from a specific scene. Interactions among neurons in multiple cortical areas are considered to be involved in attentional allocation. However, the characteristics of the encoded features and neuron responses in those attention related cortices are indefinite. Therefore, further investigations carried out in this study aim at demonstrating that unusual regions arousing more attention generally cause particular neuron responses. We suppose that visual saliency is obtained on the basis of neuron responses to contexts in natural scenes. A bottom-up visual attention model is proposed based on the self-information of neuron responses to test and verify the hypothesis. Four different color spaces are adopted and a novel entropy-based combination scheme is designed to make full use of color information. Valuable regions are highlighted while redundant backgrounds are suppressed in the saliency maps obtained by the proposed model. Comparative results reveal that the proposed model outperforms several state-of-the-art models. This study provides insights into the neuron responses based saliency detection and may underlie the neural mechanism of early visual cortices for bottom-up visual attention. PMID:25747859

  15. Pain and Analgesia: The Value of Salience Circuits

    PubMed Central

    Borsook, David; Edwards, Robert; Elman, Igor; Becerra, Lino; Levine, Jon

    2013-01-01

    Evaluating external and internal stimuli is critical to survival. Potentially tissue-damaging conditions generate sensory experiences that the organism must respond to in an appropriate, adaptive manner (e.g., withdrawal from the noxious stimulus, if possible, or seeking relief from pain and discomfort). The importance we assign to a signal generated by a noxious state, its salience, reflects our belief as to how likely the underlying situation is to impact our chance of survival. Importantly, it has been hypothesized that aberrant functioning of the brain circuits which assign salience values to stimuli may contribute to chronic pain. We describe examples of this phenomenon, including ‘feeling pain’ in the absence of a painful stimulus, reporting minimal pain in the setting of major trauma, having an ‘analgesic’ response in the absence of an active treatment, or reporting no pain relief after administration of a potent analgesic medication, which may provide critical insights into the role that salience circuits play in contributing to numerous conditions characterized by persistent pain. Collectively, a refined understanding of abnormal activity or connectivity of elements within the salience network may allow us to more effectively target interventions to relevant components of this network in patients with chronic pain. PMID:23499729

  16. Visual saliency detection based on modeling the spatial Gaussianity

    NASA Astrophysics Data System (ADS)

    Ju, Hongbin

    2015-04-01

    In this paper, a novel salient object detection method based on modeling the spatial anomalies is presented. The proposed framework is inspired by the biological mechanism that human eyes are sensitive to the unusual and anomalous objects among complex background. It is supposed that a natural image can be seen as a combination of some similar or dissimilar basic patches, and there is a direct relationship between its saliency and anomaly. Some patches share high degree of similarity and have a vast number of quantity. They usually make up the background of an image. On the other hand, some patches present strong rarity and specificity. We name these patches "anomalies". Generally, anomalous patch is a reflection of the edge or some special colors and textures in an image, and these pattern cannot be well "explained" by their surroundings. Human eyes show great interests in these anomalous patterns, and will automatically pick out the anomalous parts of an image as the salient regions. To better evaluate the anomaly degree of the basic patches and exploit their nonlinear statistical characteristics, a multivariate Gaussian distribution saliency evaluation model is proposed. In this way, objects with anomalous patterns usually appear as the outliers in the Gaussian distribution, and we identify these anomalous objects as salient ones. Experiments are conducted on the well-known MSRA saliency detection dataset. Compared with other recent developed visual saliency detection methods, our method suggests significant advantages.

  17. Human striatal activation reflects degree of stimulus saliency

    PubMed Central

    Zink, Caroline F.; Pagnoni, Giuseppe; Chappelow, Jonathan; Martin-Skurski, Megan; Berns, Gregory S.

    2007-01-01

    Salient stimuli are characterized by their capability to perturb and seize available cognitive resources. Although the striatum and its dopaminergic inputs respond to a variety of stimuli categorically defined as salient, including rewards, the relationship between striatal activity and saliency is not well understood. Specifically, it is unclear if the striatum responds in an all-or-none fashion to salient events or instead responds in a graded fashion to the degree of saliency associated with an event. Using functional magnetic resonance imaging, we measured activity in the brains of 20 participants performing a visual classification task in which they identified single digits as odd or even numbers. An auditory tone preceded each number, which was occasionally, and unexpectedly, substituted by a novel sound. The novel sounds varied in their ability to interrupt and reallocate cognitive resources (i.e., their saliency) as measured by a delay in reaction time to immediately subsequent numerical task-stimuli. The present findings demonstrate that striatal activity increases proportionally to the degree to which an unexpected novel sound interferes with the current cognitive focus, even in the absence of reward. These results suggest that activity in the human striatum reflects the level of saliency associated with a stimulus, perhaps providing a signal to reallocate limited resources to important events. PMID:16153860

  18. Visual salience modulates structure choice in relative clause production.

    PubMed

    Montag, Jessica L; MacDonald, Maryellen C

    2014-06-01

    The role of visual salience on utterance form was investigated in a picture description study. Participants heard spoken questions about animate or inanimate entities in a picture and produced a relative clause in response. Visual properties of the scenes affected production choices such that less salient inanimate entities tended to yield longer initiation latencies and to be described with passive relative clauses more than visually salient inanimates. We suggest that the participants' question-answering task can change as a function of visual salience of entities in the picture. Less salient entities require a longer visual search of the scene, which causes the speaker to notice or attend more to the non-target competitors in the picture. As a result, it becomes more important in answering the question for the speaker to contrast the target item with a salient competitor. This effect is different from other effects of visual salience, which tend to find that more salient entities take more prominent grammatical roles in the sentence. We interpret this discrepancy as evidence that visual salience does not have a single effect on sentence production, but rather its effect is modulated by task and linguistic context. PMID:25102604

  19. Manifold Ranking-Based Matrix Factorization for Saliency Detection.

    PubMed

    Tao, Dapeng; Cheng, Jun; Song, Mingli; Lin, Xu

    2016-06-01

    Saliency detection is used to identify the most important and informative area in a scene, and it is widely used in various vision tasks, including image quality assessment, image matching, and object recognition. Manifold ranking (MR) has been used to great effect for the saliency detection, since it not only incorporates the local spatial information but also utilizes the labeling information from background queries. However, MR completely ignores the feature information extracted from each superpixel. In this paper, we propose an MR-based matrix factorization (MRMF) method to overcome this limitation. MRMF models the ranking problem in the matrix factorization framework and embeds query sample labels in the coefficients. By incorporating spatial information and embedding labels, MRMF enforces similar saliency values on neighboring superpixels and ranks superpixels according to the learned coefficients. We prove that the MRMF has good generalizability, and develops an efficient optimization algorithm based on the Nesterov method. Experiments using popular benchmark data sets illustrate the promise of MRMF compared with the other state-of-the-art saliency detection methods. PMID:26277008

  20. Low Memory Implementation of Saliency Map Using Strip-Based Method

    NASA Astrophysics Data System (ADS)

    Ngau, Christopher Wing Hong; Ang, Li-Minn; Seng, Kah Phooi

    Works in the area of visual saliency are expanding rapidly where visual salience is beginning to find importance in many multimedia and object detection applications. The core of the visual saliency models is the saliency map where information from various features such as intensity, colour, and orientation are encoded onto a single master map. However, the required amount of memory to hold the related maps in the computation of the saliency map is large. This could be seen as a potential complication in hardware constrained environment. In this paper, a low memory implementation of a saliency map using strip-based method is proposed. Simulation results showed that the strip-based method is able to provide a reasonable saliency map while keeping the memory requirements low.

  1. No-reference video quality assessment of H.264 video streams based on semantic saliency maps

    NASA Astrophysics Data System (ADS)

    Boujut, H.; Benois-Pineau, J.; Ahmed, T.; Hadar, O.; Bonnet, P.

    2012-01-01

    The paper contributes to No-Reference video quality assessment of broadcasted HD video over IP networks and DVB. In this work we have enhanced our bottom-up spatio-temporal saliency map model by considering semantics of the visual scene. Thus we propose a new saliency map model based on face detection that we called semantic saliency map. A new fusion method has been proposed to merge the bottom-up saliency maps with the semantic saliency map. We show that our NR metric WMBER weighted by the spatio-temporal-semantic saliency map provides higher results then the WMBER weighted by the bottom-up spatio-temporal saliency map. Tests are performed on two H.264/AVC video databases for video quality assessment over lossy networks.

  2. A No-Reference Texture Regularity Metric Based on Visual Saliency.

    PubMed

    Varadarajan, Srenivas; Karam, Lina J

    2015-09-01

    This paper presents a no-reference perceptual metric that quantifies the degree of perceived regularity in textures. The metric is based on the similarity of visual attention (VA) of the textural primitives and the periodic spatial distribution of foveated fixation regions throughout the image. A ground-truth eye-tracking database for textures is also generated as part of this paper and is used to evaluate the performance of the most popular VA models. Using the saliency map generated by the best VA model, the proposed texture regularity metric is computed. It is shown through subjective testing that the proposed metric has a strong correlation with the mean opinion score for the perceived regularity of textures. The proposed texture regularity metric can be used to improve the quality and performance of many image processing applications like texture synthesis, texture compression, and content-based image retrieval. PMID:25826803

  3. Vegetarianism and food perception. Selective visual attention to meat pictures.

    PubMed

    Stockburger, Jessica; Renner, Britta; Weike, Almut I; Hamm, Alfons O; Schupp, Harald T

    2009-04-01

    Vegetarianism provides a model system to examine the impact of negative affect towards meat, based on ideational reasoning. It was hypothesized that meat stimuli are efficient attention catchers in vegetarians. Event-related brain potential recordings served to index selective attention processes at the level of initial stimulus perception. Consistent with the hypothesis, late positive potentials to meat pictures were enlarged in vegetarians compared to omnivores. This effect was specific for meat pictures and obtained during passive viewing and an explicit attention task condition. These findings demonstrate the attention capture of food stimuli, deriving affective salience from ideational reasoning and symbolic meaning. PMID:18996158

  4. Attention regulates the plasticity of multisensory timing

    PubMed Central

    Heron, James; Roach, Neil W.; Whitaker, David; Hanson, James V. M.

    2012-01-01

    Evidence suggests than human time perception is likely to reflect an ensemble of recent temporal experience. For example, prolonged exposure to consistent temporal patterns can adaptively realign the perception of event order, both within and between sensory modalities. In addition, the observation that ‘a watched pot never boils’ serves to illustrate the fact that dynamic shifts in our attentional state can also produce marked distortions in our temporal estimates. In the current study we provide evidence for a hitherto unknown link between adaptation, temporal perception and our attentional state. We show that our ability to use recent sensory history as a perceptual baseline for ongoing temporal judgments is subject to striking top-down modulation via shifts in the observer’s selective attention. Specifically, attending to the temporal structure of asynchronous auditory and visual adapting stimuli generates a substantial increase in the temporal recalibration induced by these stimuli. We propose a conceptual framework accounting for our findings whereby attention modulates the perceived salience of temporal patterns. This heightened salience allows the formation of audiovisual perceptual ‘objects’, defined solely by their temporal structure. Repeated exposure to these objects induces high-level pattern adaptation effects, akin to those found in visual and auditory domains. PMID:20584179

  5. Attention regulates the plasticity of multisensory timing.

    PubMed

    Heron, James; Roach, Neil W; Whitaker, David; Hanson, James V M

    2010-05-01

    Evidence suggests than human time perception is likely to reflect an ensemble of recent temporal experience. For example, prolonged exposure to consistent temporal patterns can adaptively realign the perception of event order, both within and between sensory modalities (e.g. Fujisaki et al., 2004 Nat. Neurosci., 7, 773-778). In addition, the observation that 'a watched pot never boils' serves to illustrate the fact that dynamic shifts in our attentional state can also produce marked distortions in our temporal estimates. In the current study we provide evidence for a hitherto unknown link between adaptation, temporal perception and our attentional state. We show that our ability to use recent sensory history as a perceptual baseline for ongoing temporal judgments is subject to striking top-down modulation via shifts in the observer's selective attention. Specifically, attending to the temporal structure of asynchronous auditory and visual adapting stimuli generates a substantial increase in the temporal recalibration induced by these stimuli. We propose a conceptual framework accounting for our findings whereby attention modulates the perceived salience of temporal patterns. This heightened salience allows the formation of audiovisual perceptual 'objects', defined solely by their temporal structure. Repeated exposure to these objects induces high-level pattern adaptation effects, akin to those found in visual and auditory domains (e.g. Leopold & Bondar (2005) Fitting the Mind to the World: Adaptation and Aftereffects in High-Level Vision. Oxford University Press, Oxford, 189-211; Schweinberger et al. (2008) Curr. Biol., 18, 684-688). PMID:20584179

  6. Switch wear leveling

    SciTech Connect

    Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

    2015-09-01

    An apparatus for switch wear leveling includes a switching module that controls switching for two or more pairs of switches in a switching power converter. The switching module controls switches based on a duty cycle control technique and closes and opens each switch in a switching sequence. The pairs of switches connect to a positive and negative terminal of a DC voltage source. For a first switching sequence a first switch of a pair of switches has a higher switching power loss than a second switch of the pair of switches. The apparatus includes a switch rotation module that changes the switching sequence of the two or more pairs of switches from the first switching sequence to a second switching sequence. The second switch of a pair of switches has a higher switching power loss than the first switch of the pair of switches during the second switching sequence.

  7. A neural computational model for bottom-up attention with invariant and overcomplete representation

    PubMed Central

    2012-01-01

    Background An important problem in selective attention is determining the ways the primary visual cortex contributes to the encoding of bottom-up saliency and the types of neural computation that are effective to model this process. To address this problem, we constructed a two-layered network that satisfies the neurobiological constraints of the primary visual cortex to detect salient objects. We carried out experiments on both synthetic images and natural images to explore the influences of different factors, such as network structure, the size of each layer, the type of suppression and the combination strategy, on saliency detection performance. Results The experimental results statistically demonstrated that the type and scale of filters contribute greatly to the encoding of bottom-up saliency. These two factors correspond to the mechanisms of invariant encoding and overcomplete representation in the primary visual cortex. Conclusions (1) Instead of constructing Gabor functions or Gaussian pyramids filters for feature extraction as traditional attention models do, we learn overcomplete basis sets from natural images to extract features for saliency detection. Experiments show that given the proper layer size and a robust combination strategy, the learned overcomplete basis set outperforms a complete set and Gabor pyramids in visual saliency detection. This finding can potentially be applied in task-dependent and supervised object detection. (2) A hierarchical coding model that can represent invariant features, is designed for the pre-attentive stage of bottom-up attention. This coding model improves robustness to noises and distractions and improves the ability of detecting salient structures, such as collinear and co-circular structures, and several composite stimuli. This result indicates that invariant representation contributes to saliency detection (popping out) in bottom-up attention. The aforementioned perspectives will significantly contribute to the in

  8. Discriminatively trained part based model armed with biased saliency

    NASA Astrophysics Data System (ADS)

    Yu, Huapeng; Chang, Yongxin; Lu, Pei; Xu, Zhiyong; Fu, Chengyu; Wang, Yafei

    2015-02-01

    Discriminatively trained Part based Model (DPM) is one of the state-of-the-art object detectors. However, DPM complies little with real vision procedure. In this paper, we try arming DPM with biologically inspired approaches. On the one hand, we use Gabor instead of Histogram of Oriented Gradient (HOG) as low level features to simulate the receptive fields of simple cells. We show Gabor outperforms or is on par with HOG. On the other hand, we learn biased saliency of the object with the same Gabor features to simulate the search procedure of real vision. We combine DPM and biased saliency in a single Bayesian framework, which at least partially reflects the interactions between top-down and bottom-up vision procedures. We show these biologically inspired procedures can effectively improve the performance and efficiency of DPM. We present experimental results on both challenging PASCAL VOC2007 dataset and publicly available sequences.

  9. Of wealth and death: materialism, mortality salience, and consumption behavior.

    PubMed

    Kasser, T; Sheldon, K M

    2000-07-01

    Theoretical work suggests that feelings of insecurity produce materialistic behavior, but most empirical evidence is correlational in nature. We therefore experimentally activated feelings of insecurity by having some subjects write short essays about death (mortality-salience condition). In Study 1, subjects in the mortality-salience condition, compared with subjects who wrote about a neutral topic, had higher financial expectations for themselves 15 years in the future, in terms of both their overall worth and the amount they would be spending on pleasurable items such as clothing and entertainment. Study 2 extended these findings by demonstrating that subjects exposed to death became more greedy and consumed more resources in a forest-management game. Results are discussed with regard to humanistic and terror-management theories of materialism. PMID:11273398

  10. Salience of unique hues and implications for color theory

    PubMed Central

    Wool, Lauren E.; Komban, Stanley J.; Kremkow, Jens; Jansen, Michael; Li, Xiaobing; Alonso, Jose-Manuel; Zaidi, Qasim

    2015-01-01

    The unique hues—blue, green, yellow, red—form the fundamental dimensions of opponent-color theories, are considered universal across languages, and provide useful mental representations for structuring color percepts. However, there is no neural evidence for them from neurophysiology or low-level psychophysics. Tapping a higher prelinguistic perceptual level, we tested whether unique hues are particularly salient in search tasks. We found no advantage for unique hues over their nonunique complementary colors. However, yellowish targets were detected faster, more accurately, and with fewer saccades than their complementary bluish targets (including unique blue), while reddish-greenish pairs were not significantly different in salience. Similarly, local field potentials in primate V1 exhibited larger amplitudes and shorter latencies for yellowish versus bluish stimuli, whereas this effect was weaker for reddish versus greenish stimuli. Consequently, color salience is affected more by early neural response asymmetries than by any possible mental or neural representation of unique hues. PMID:25761328

  11. Exploiting Surroundedness for Saliency Detection: A Boolean Map Approach.

    PubMed

    Zhang, Jianming; Sclaroff, Stan

    2016-05-01

    We demonstrate the usefulness of surroundedness for eye fixation prediction by proposing a Boolean Map based Saliency model (BMS). In our formulation, an image is characterized by a set of binary images, which are generated by randomly thresholding the image's feature maps in a whitened feature space. Based on a Gestalt principle of figure-ground segregation, BMS computes a saliency map by discovering surrounded regions via topological analysis of Boolean maps. Furthermore, we draw a connection between BMS and the Minimum Barrier Distance to provide insight into why and how BMS can properly captures the surroundedness cue via Boolean maps. The strength of BMS is verified by its simplicity, efficiency and superior performance compared with 10 state-of-the-art methods on seven eye tracking benchmark datasets. PMID:26336114

  12. Modeling Visual Exploration in Rhesus Macaques with Bottom-Up Salience and Oculomotor Statistics.

    PubMed

    König, Seth D; Buffalo, Elizabeth A

    2016-01-01

    There is a growing interest in studying biological systems in natural settings, in which experimental stimuli are less artificial and behavior is less controlled. In primate vision research, free viewing of complex images has elucidated novel neural responses, and free viewing in humans has helped discover attentional and behavioral impairments in patients with neurological disorders. In order to fully interpret data collected from free viewing of complex scenes, it is critical to better understand what aspects of the stimuli guide viewing behavior. To this end, we have developed a novel viewing behavior model called a Biased Correlated Random Walk (BCRW) to describe free viewing behavior during the exploration of complex scenes in monkeys. The BCRW can predict fixation locations better than bottom-up salience. Additionally, we show that the BCRW can be used to test hypotheses regarding specific attentional mechanisms. For example, we used the BCRW to examine the source of the central bias in fixation locations. Our analyses suggest that the central bias may be caused by a natural tendency to reorient the eyes toward the center of the stimulus, rather than a photographer's bias to center salient items in a scene. Taken together these data suggest that the BCRW can be used to further our understanding of viewing behavior and attention, and could be useful in optimizing stimulus and task design. PMID:27445721

  13. Modeling Visual Exploration in Rhesus Macaques with Bottom-Up Salience and Oculomotor Statistics

    PubMed Central

    König, Seth D.; Buffalo, Elizabeth A.

    2016-01-01

    There is a growing interest in studying biological systems in natural settings, in which experimental stimuli are less artificial and behavior is less controlled. In primate vision research, free viewing of complex images has elucidated novel neural responses, and free viewing in humans has helped discover attentional and behavioral impairments in patients with neurological disorders. In order to fully interpret data collected from free viewing of complex scenes, it is critical to better understand what aspects of the stimuli guide viewing behavior. To this end, we have developed a novel viewing behavior model called a Biased Correlated Random Walk (BCRW) to describe free viewing behavior during the exploration of complex scenes in monkeys. The BCRW can predict fixation locations better than bottom-up salience. Additionally, we show that the BCRW can be used to test hypotheses regarding specific attentional mechanisms. For example, we used the BCRW to examine the source of the central bias in fixation locations. Our analyses suggest that the central bias may be caused by a natural tendency to reorient the eyes toward the center of the stimulus, rather than a photographer's bias to center salient items in a scene. Taken together these data suggest that the BCRW can be used to further our understanding of viewing behavior and attention, and could be useful in optimizing stimulus and task design. PMID:27445721

  14. Organization of the channel-switching process in parallel computer systems based on a matrix optical switch

    NASA Technical Reports Server (NTRS)

    Golomidov, Y. V.; Li, S. K.; Popov, S. A.; Smolov, V. B.

    1986-01-01

    After a classification and analysis of electronic and optoelectronic switching devices, the design principles and structure of a matrix optical switch is described. The switching and pair-exclusion operations in this type of switch are examined, and a method for the optical switching of communication channels is elaborated. Finally, attention is given to the structural organization of a parallel computer system with a matrix optical switch.

  15. An experimental field study of weight salience and food choice.

    PubMed

    Incollingo Rodriguez, Angela C; Finch, Laura E; Buss, Julia; Guardino, Christine M; Tomiyama, A Janet

    2015-06-01

    Laboratory research has found that individuals will consume more calories and make unhealthy food choices when in the presence of an overweight individual, sometimes even regardless of what that individual is eating. This study expanded these laboratory paradigms to the field to examine how weight salience influences eating in the real world. More specifically, we tested the threshold of the effect of weight salience of food choice to see if a more subtle weight cue (e.g., images) would be sufficient to affect food choice. Attendees (N = 262) at Obesity Week 2013, a weight-salient environment, viewed slideshows containing an image of an overweight individual, an image of a thin individual, or no image (text only), and then selected from complimentary snacks. Results of ordinal logistic regression analysis showed that participants who viewed the image of the overweight individual had higher odds of selecting the higher calorie snack compared to those who viewed the image of the thin individual (OR = 1.77, 95% CI = [1.04, 3.04]), or no image (OR = 2.42, 95% CI = [1.29, 4.54]). Perceiver BMI category did not moderate the influence of image on food choice, as these results occurred regardless of participant BMI. These findings suggest that in the context of societal weight salience, weight-related cues alone may promote unhealthy eating in the general public. PMID:25698080

  16. Multiview saliency detection based on improved multimanifold ranking

    NASA Astrophysics Data System (ADS)

    Shi, Yanjiao; Yi, Yugen; Zhang, Ke; Kong, Jun; Zhang, Ming; Wang, Jianzhong

    2014-11-01

    As an important problem in computer vision, saliency detection is essential for image segmentation, super-resolution, object recognition, and so on. We propose a saliency detection method for images. Instead of using contrast between salient regions and their surrounding areas, both cues from salient and nonsalient regions are considered in our study. Based on these cues, an improved multimanifold ranking algorithm is proposed. In our algorithm, features from multiple views are utilized and the different contributions of these multiview features are taken into account. Moreover, an iterative updating optimization scheme is explored to solve the objective function, during which the feature fusion is performed. After two-stage ranking by the improved multimanifold ranking algorithm, each image patch can be assigned a ranking score, which determines the final saliency. The proposed method is evaluated on four public datasets and is compared with the state-of-the-art methods. Experimental results indicate that the proposed method outperforms existing schemes both in qualitative and quantitative comparisons.

  17. Impact of feature saliency on visual category learning

    PubMed Central

    Hammer, Rubi

    2015-01-01

    People have to sort numerous objects into a large number of meaningful categories while operating in varying contexts. This requires identifying the visual features that best predict the ‘essence’ of objects (e.g., edibility), rather than categorizing objects based on the most salient features in a given context. To gain this capacity, visual category learning (VCL) relies on multiple cognitive processes. These may include unsupervised statistical learning, that requires observing multiple objects for learning the statistics of their features. Other learning processes enable incorporating different sources of supervisory information, alongside the visual features of the categorized objects, from which the categorical relations between few objects can be deduced. These deductions enable inferring that objects from the same category may differ from one another in some high-saliency feature dimensions, whereas lower-saliency feature dimensions can best differentiate objects from distinct categories. Here I illustrate how feature saliency affects VCL, by also discussing kinds of supervisory information enabling reflective categorization. Arguably, principles debated here are often being ignored in categorization studies. PMID:25954220

  18. A comparative study of feature-salience ranking techniques.

    PubMed

    Wang, W; Jones, P; Partridge, D

    2001-07-01

    We assess the relative merits of a number of techniques designed to determine the relative salience of the elements of a feature set with respect to their ability to predict a category outcome-for example, which features of a character contribute most to accurate character recognition. A number of different neural-net-based techniques have been proposed (by us and others) in addition to a standard statistical technique, and we add a technique based on inductively generated decision trees. The salience of the features that compose a proposed set is an important problem to solve efficiently and effectively, not only for neural computing technology but also in order to provide a sound basis for any attempt to design an optimal computational system. The focus of this study is the efficiency and the effectiveness with which high-salience subsets of features can be identified in the context of ill-understood and potentially noisy real-world data. Our two simple approaches, weight clamping using a neural network and feature ranking using a decision tree, generally provide a good, consistent ordering of features. In addition, linear correlation often works well. PMID:11440599

  19. Low-Complexity Saliency Detection Algorithm for Fast Perceptual Video Coding

    PubMed Central

    Liu, Pengyu; Jia, Kebin

    2013-01-01

    A low-complexity saliency detection algorithm for perceptual video coding is proposed; low-level encoding information is adopted as the characteristics of visual perception analysis. Firstly, this algorithm employs motion vector (MV) to extract temporal saliency region through fast MV noise filtering and translational MV checking procedure. Secondly, spatial saliency region is detected based on optimal prediction mode distributions in I-frame and P-frame. Then, it combines the spatiotemporal saliency detection results to define the video region of interest (VROI). The simulation results validate that the proposed algorithm can avoid a large amount of computation work in the visual perception characteristics analysis processing compared with other existing algorithms; it also has better performance in saliency detection for videos and can realize fast saliency detection. It can be used as a part of the video standard codec at medium-to-low bit-rates or combined with other algorithms in fast video coding. PMID:24489495

  20. Development of Attentional Control of Verbal Auditory Perception from Middle to Late Childhood: Comparisons to Healthy Aging

    ERIC Educational Resources Information Center

    Passow, Susanne; Müller, Maike; Westerhausen, René; Hugdahl, Kenneth; Wartenburger, Isabell; Heekeren, Hauke R.; Lindenberger, Ulman; Li, Shu-Chen

    2013-01-01

    Multitalker situations confront listeners with a plethora of competing auditory inputs, and hence require selective attention to relevant information, especially when the perceptual saliency of distracting inputs is high. This study augmented the classical forced-attention dichotic listening paradigm by adding an interaural intensity manipulation…

  1. Decreased Intra- and Inter-Salience Network Functional Connectivity is Related to Trait Anxiety in Adolescents

    PubMed Central

    Geng, Haiyang; Li, Xuebing; Chen, Jie; Li, Xinying; Gu, Ruolei

    2016-01-01

    Objective: Adolescence is a critical period for the vulnerability of anxiety. Imaging studies focusing on adolescents' susceptibility to anxiety suggest that the different development trajectories between the limbic system and the executive control system may play important roles in this phenomenon. However, few studies have explored the brain basis of this susceptibility from the perspective of functional networks. The salience network (SN) consists of a series of key limbic and prefrontal regions that are engaged in the development of anxiety, such as the amygdala, anterior insula (AI), and dorsal anterior cingulate cortex (dACC). Intra- and inter-network connections in this system play essential roles in bottom-up attention and top-down regulation of anxiety, nevertheless, little is known about whether the SN-centered connections are associated with trait anxiety (i.e., susceptibility to anxiety) in adolescents. Method: Here, we applied resting-state functional magnetic resonance imaging (fMRI) to explore the relationship between intra- and inter-network functional connectivity (FC) of the SN and trait anxiety in adolescents using the amygdala, AI and dACC as the regions of interest (ROI). Results: We found that trait anxiety levels were inversely associated with both characteristic AI-dACC FC in the SN and distributed inter-network FC between the SN and multiple functional systems, which included the default mode network and the executive control network. Conclusions: Our results indicate that weaker intra- and inter-network FC of the SN was linked to higher trait anxiety among adolescents, and it may underlie altered salience processing and cognitive regulation. PMID:26834594

  2. 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…

  3. The role of magnocellular signals in oculomotor attentional capture.

    PubMed

    Leonard, Carly J; Luck, Steven J

    2011-01-01

    While it is known that salient distractors often capture covert and overt attention, it is unclear whether salience signals that stem from magnocellular visual input have a more dominant role in oculomotor capture than those that result from parvocellular input. Because of the direct anatomical connections between the magnocellular pathway and the superior colliculus, salience signals generated from the magnocellular pathway may produce greater oculomotor capture than those from the parvocellular pathway, which could be potentially harder to overcome with "top-down," goal-directed guidance. Although previous research has addressed this with regard to magnocellular transients, in the current research, we investigated whether a static singleton distractor defined along a dimension visible to the magnocellular pathway would also produce enhanced oculomotor capture. In two experiments, we addressed this possibility by comparing a parvo-biased singleton condition, in which the distractor was defined by isoluminant chromatic color contrast, with a magno + parvo singleton condition, in which the distractor also differed in luminance from the surrounding objects. In both experiments, magno + parvo singletons elicited faster eye movements than parvo-only singletons, presumably reflecting faster information transmission in the magnocellular pathway, but magno + parvo singletons were not significantly more likely to produce oculomotor capture. Thus, although magnocellular salience signals are available more rapidly, they have no sizable advantage over parvocellular salience signals in controlling oculomotor orienting when all stimuli have a common onset. PMID:22076486

  4. Comparing Switch Costs: Alternating Runs and Explicit Cuing

    ERIC Educational Resources Information Center

    Altmann, Erik M.

    2007-01-01

    The task-switching literature routinely conflates different operational definitions of switch cost, its predominant behavioral measure. This article is an attempt to draw attention to differences between the two most common definitions, alternating-runs switch cost (ARS) and explicit-cuing switch cost (ECS). ARS appears to include both the costs…

  5. What causes aberrant salience in schizophrenia? A role for impaired short-term habituation and the GRIA1 (GluA1) AMPA receptor subunit

    PubMed Central

    Barkus, C; Sanderson, DJ; Rawlins, JNP; Walton, ME; Harrison, PJ; Bannerman, DM

    2014-01-01

    The GRIA1 locus, encoding the GluA1 (also known as GluRA or GluR1) AMPA glutamate receptor subunit, shows genome-wide association to schizophrenia. As well as extending the evidence that glutamatergic abnormalities play a key role in the disorder, this finding draws attention to the behavioural phenotype of Gria1 knockout mice. These mice show deficits in short-term habituation. Importantly, under some conditions the attention being paid to a recently presented neutral stimulus can actually increase rather than decrease (sensitization). We propose that this mouse phenotype represents a cause of aberrant salience and, in turn, that aberrant salience (and the resulting positive symptoms) in schizophrenia may arise, at least in part, from a glutamatergic genetic predisposition and a deficit in short-term habituation. This proposal links an established risk gene with a psychological process central to psychosis, and is supported by findings of comparable deficits in short-term habituation in mice lacking the NMDAR receptor subunit Grin2a (which also shows association to schizophrenia). Since aberrant salience is primarily a dopaminergic phenomenon, the model supports the view that the dopaminergic abnormalities can be downstream of a glutamatergic aetiology. Finally, we suggest that, as illustrated here, the real value of genetically modified mice is not as ‘models of schizophrenia’, but as experimental tools which can link genomic discoveries with psychological processes, and help elucidate the underlying neural mechanisms. PMID:25224260

  6. Attention's Accelerator.

    PubMed

    Reinhart, Robert M G; McClenahan, Laura J; Woodman, Geoffrey F

    2016-06-01

    How do people get attention to operate at peak efficiency in high-pressure situations? We tested the hypothesis that the general mechanism that allows this is the maintenance of multiple target representations in working and long-term memory. We recorded subjects' event-related potentials (ERPs) indexing the working memory and long-term memory representations used to control attention while performing visual search. We found that subjects used both types of memories to control attention when they performed the visual search task with a large reward at stake, or when they were cued to respond as fast as possible. However, under normal circumstances, one type of target memory was sufficient for slower task performance. The use of multiple types of memory representations appears to provide converging top-down control of attention, allowing people to step on the attentional accelerator in a variety of high-pressure situations. PMID:27056975

  7. Emotional content of an image attracts attention more than visually salient features in various signal-to-noise ratio conditions.

    PubMed

    Pilarczyk, Joanna; Kuniecki, Michał

    2014-01-01

    Emotional images are processed in a prioritized manner, attracting attention almost immediately. In the present study we used eye tracking to reveal what type of features within neutral, positive, and negative images attract early visual attention: semantics, visual saliency, or their interaction. Semantic regions of interest were selected by observers, while visual saliency was determined using the Graph-Based Visual Saliency model. Images were transformed by adding pink noise in several proportions to be presented in a sequence of increasing and decreasing clarity. Locations of the first two fixations were analyzed. The results showed dominance of semantic features over visual saliency in attracting attention. This dominance was linearly related to the signal-to-noise ratio. Semantic regions were fixated more often in emotional images than in neutral ones, if signal-to-noise ratio was high enough to allow participants to comprehend the gist of a scene. Visual saliency on its own did not attract attention above chance, even in the case of pure noise images. Regions both visually salient and semantically relevant attracted a similar amount of fixation compared to semantic regions alone, or even more in the case of neutral pictures. Results provide evidence for fast and robust detection of semantically relevant features. PMID:25294641

  8. Audition dominates vision in duration perception irrespective of salience, attention, and temporal discriminability

    PubMed Central

    Ortega, Laura; Guzman-Martinez, Emmanuel; Grabowecky, Marcia; Suzuki, Satoru

    2014-01-01

    Whereas the visual modality tends to dominate over the auditory modality in bimodal spatial perception, the auditory modality tends to dominate over the visual modality in bimodal temporal perception. Recent results suggest that the visual modality dominates bimodal spatial perception because spatial discriminability is typically greater for the visual than auditory modality; accordingly, visual dominance is eliminated or reversed when visual-spatial discriminability is reduced by degrading visual stimuli to be equivalent or inferior to auditory spatial discriminability. Thus, for spatial perception, the modality that provides greater discriminability dominates. Here we ask whether auditory dominance in duration perception is similarly explained by factors that influence the relative quality of auditory and visual signals. In contrast to the spatial results, the auditory modality dominated over the visual modality in bimodal duration perception even when the auditory signal was clearly weaker, when the auditory signal was ignored (i.e., the visual signal was selectively attended), and when the temporal discriminability was equivalent for the auditory and visual signals. Thus, unlike spatial perception where the modality carrying more discriminable signals dominates, duration perception seems to be mandatorily linked to auditory processing under most circumstances. PMID:24806403

  9. Audition dominates vision in duration perception irrespective of salience, attention, and temporal discriminability.

    PubMed

    Ortega, Laura; Guzman-Martinez, Emmanuel; Grabowecky, Marcia; Suzuki, Satoru

    2014-07-01

    Whereas the visual modality tends to dominate over the auditory modality in bimodal spatial perception, the auditory modality tends to dominate over the visual modality in bimodal temporal perception. Recent results suggest that the visual modality dominates bimodal spatial perception because spatial discriminability is typically greater for the visual than for the auditory modality; accordingly, visual dominance is eliminated or reversed when visual-spatial discriminability is reduced by degrading visual stimuli to be equivalent or inferior to auditory spatial discriminability. Thus, for spatial perception, the modality that provides greater discriminability dominates. Here, we ask whether auditory dominance in duration perception is similarly explained by factors that influence the relative quality of auditory and visual signals. In contrast to the spatial results, the auditory modality dominated over the visual modality in bimodal duration perception even when the auditory signal was clearly weaker, when the auditory signal was ignored (i.e., the visual signal was selectively attended), and when the temporal discriminability was equivalent for the auditory and visual signals. Thus, unlike spatial perception, where the modality carrying more discriminable signals dominates, duration perception seems to be mandatorily linked to auditory processing under most circumstances. PMID:24806403

  10. Children Induce an Enhanced Attentional Blink in Child Molesters

    ERIC Educational Resources Information Center

    Beech, Anthony R.; Kalmus, Ellis; Tipper, Steven P.; Baudouin, Jean-Yves; Flak, Vanja; Humphreys, Glyn W.

    2008-01-01

    The attentional blink (AB) is a robust phenomenon that has been consistently reported in the cognitive literature. The AB is found when two target images (T1, T2) are presented within 500 ms of each other and errors are induced on the perceptual report of T2. The AB may increase when T1 has some salience to the viewer. This study examined the…

  11. 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…

  12. Optical switches and switching methods

    DOEpatents

    Doty, Michael

    2008-03-04

    A device and method for collecting subject responses, particularly during magnetic imaging experiments and testing using a method such as functional MRI. The device comprises a non-metallic input device which is coupled via fiber optic cables to a computer or other data collection device. One or more optical switches transmit the subject's responses. The input device keeps the subject's fingers comfortably aligned with the switches by partially immobilizing the forearm, wrist, and/or hand of the subject. Also a robust nonmetallic switch, particularly for use with the input device and methods for optical switching.

  13. Motivational Salience Signal in the Basal Forebrain Is Coupled with Faster and More Precise Decision Speed

    PubMed Central

    Avila, Irene; Lin, Shih-Chieh

    2014-01-01

    The survival of animals depends critically on prioritizing responses to motivationally salient stimuli. While it is generally believed that motivational salience increases decision speed, the quantitative relationship between motivational salience and decision speed, measured by reaction time (RT), remains unclear. Here we show that the neural correlate of motivational salience in the basal forebrain (BF), defined independently of RT, is coupled with faster and also more precise decision speed. In rats performing a reward-biased simple RT task, motivational salience was encoded by BF bursting response that occurred before RT. We found that faster RTs were tightly coupled with stronger BF motivational salience signals. Furthermore, the fraction of RT variability reflecting the contribution of intrinsic noise in the decision-making process was actively suppressed in faster RT distributions with stronger BF motivational salience signals. Artificially augmenting the BF motivational salience signal via electrical stimulation led to faster and more precise RTs and supports a causal relationship. Together, these results not only describe for the first time, to our knowledge, the quantitative relationship between motivational salience and faster decision speed, they also reveal the quantitative coupling relationship between motivational salience and more precise RT. Our results further establish the existence of an early and previously unrecognized step in the decision-making process that determines both the RT speed and variability of the entire decision-making process and suggest that this novel decision step is dictated largely by the BF motivational salience signal. Finally, our study raises the hypothesis that the dysregulation of decision speed in conditions such as depression, schizophrenia, and cognitive aging may result from the functional impairment of the motivational salience signal encoded by the poorly understood noncholinergic BF neurons. PMID:24642480

  14. Motivational salience signal in the basal forebrain is coupled with faster and more precise decision speed.

    PubMed

    Avila, Irene; Lin, Shih-Chieh

    2014-03-01

    The survival of animals depends critically on prioritizing responses to motivationally salient stimuli. While it is generally believed that motivational salience increases decision speed, the quantitative relationship between motivational salience and decision speed, measured by reaction time (RT), remains unclear. Here we show that the neural correlate of motivational salience in the basal forebrain (BF), defined independently of RT, is coupled with faster and also more precise decision speed. In rats performing a reward-biased simple RT task, motivational salience was encoded by BF bursting response that occurred before RT. We found that faster RTs were tightly coupled with stronger BF motivational salience signals. Furthermore, the fraction of RT variability reflecting the contribution of intrinsic noise in the decision-making process was actively suppressed in faster RT distributions with stronger BF motivational salience signals. Artificially augmenting the BF motivational salience signal via electrical stimulation led to faster and more precise RTs and supports a causal relationship. Together, these results not only describe for the first time, to our knowledge, the quantitative relationship between motivational salience and faster decision speed, they also reveal the quantitative coupling relationship between motivational salience and more precise RT. Our results further establish the existence of an early and previously unrecognized step in the decision-making process that determines both the RT speed and variability of the entire decision-making process and suggest that this novel decision step is dictated largely by the BF motivational salience signal. Finally, our study raises the hypothesis that the dysregulation of decision speed in conditions such as depression, schizophrenia, and cognitive aging may result from the functional impairment of the motivational salience signal encoded by the poorly understood noncholinergic BF neurons. PMID:24642480

  15. 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

  16. Aberrant structural and functional connectivity in the salience network and central executive network circuit in schizophrenia.

    PubMed

    Chen, Quan; Chen, Xingui; He, Xiaoxuan; Wang, Lu; Wang, Kai; Qiu, Bensheng

    2016-08-01

    Consistent structural and functional abnormities have been detected in the salience network (SN) and the central-executive network (CEN) in schizophrenia. SN, known for its critical role in switching CEN and default-mode network (DMN) during cognitively demanding tasks, is proved to show aberrant regulation on the interaction between DMN and CEN in schizophrenia. However, it has not been elucidated whether there is a direct alteration of structural and functional connectivity between SN and CEN. 22 schizophrenia patients and 21 healthy controls were recruited for functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) in present study. The results show that schizophrenia patients had lower fractional anisotropy (FA) in right inferior long fasciculus (ILF), left inferior fronto-occipital fasciculus (IFOF) and callosal body than healthy controls. Significantly reduced functional connectivity was also found between right fronto-insular cortex (rFIC) and right posterior parietal cortex (rPPC). FA in right ILF was positively correlated with the functional connectivity of rFIC-rPPC. Therefore, we proposed a disruption of structural and functional connectivity and a positive anatomo-functional relationship in SN-CEN circuit, which might account for a core feature of schizophrenia. PMID:27233217

  17. The concept of salience network dysfunction in schizophrenia: from neuroimaging observations to therapeutic opportunities.

    PubMed

    Palaniyappan, L; White, T P; Liddle, P F

    2012-01-01

    A large body of neuroimaging literature suggests that distributed regions in the brain form coordinated largescale networks that show reliable patterns of connectivity when observed using either functional or structural magnetic resonance imaging (MRI) methods. Functional activation within these networks provides a robust and reliable representation of dynamic brain states observed during information processing. One such network comprised of anterior frontoinsular cortex (aFI) and anterior cingulate cortex (ACC) is called the Salience Network (SN). SN has been identified as a system that enables the switch between various dynamic brain states. SN dysfunction has been proposed as a mechanistic model for several core symptoms of schizophrenia. In this review, we explore how various risk factors of schizophrenia could operate through the dysfunctional SN to generate symptoms of psychosis. We also consider the putative neurochemical basis for the SN dysfunction in schizophrenia, and suggest that the SN dysfunction is a viable therapeutic target for a combined pharmacological and cognitive training treatment approach. This combination approach, termed as Brain Network Modulation, could exploit neuronal plasticity to reverse a key pathophysiological deficit in schizophrenia. PMID:23279173

  18. Visual Attention to Print-Salient and Picture-Salient Environmental Print in Young Children

    ERIC Educational Resources Information Center

    Neumann, Michelle M.; Summerfield, Katelyn; Neumann, David L.

    2015-01-01

    Environmental print is composed of words and contextual cues such as logos and pictures. The salience of the contextual cues may influence attention to words and thus the potential of environmental print in promoting early reading development. The present study explored this by presenting pre-readers (n = 20) and beginning readers (n = 16) with…

  19. What Does Distractibility in ADHD Reveal about Mechanisms for Top-Down Attentional Control?

    ERIC Educational Resources Information Center

    Friedman-Hill, Stacia R.; Wagman, Meryl R.; Gex, Saskia E.; Pine, Daniel S.; Leibenluft, Ellen; Ungerleider, Leslie G.

    2010-01-01

    In this study, we attempted to clarify whether distractibility in ADHD might arise from increased sensory-driven interference or from inefficient top-down control. We employed an attentional filtering paradigm in which discrimination difficulty and distractor salience (amount of image "graying") were parametrically manipulated. Increased…

  20. Classification of Eye Fixation Related Potentials for Variable Stimulus Saliency

    PubMed Central

    Wenzel, Markus A.; Golenia, Jan-Eike; Blankertz, Benjamin

    2016-01-01

    Objective: Electroencephalography (EEG) and eye tracking can possibly provide information about which items displayed on the screen are relevant for a person. Exploiting this implicit information promises to enhance various software applications. The specific problem addressed by the present study is that items shown in real applications are typically diverse. Accordingly, the saliency of information, which allows to discriminate between relevant and irrelevant items, varies. As a consequence, recognition can happen in foveal or in peripheral vision, i.e., either before or after the saccade to the item. Accordingly, neural processes related to recognition are expected to occur with a variable latency with respect to the eye movements. The aim was to investigate if relevance estimation based on EEG and eye tracking data is possible despite of the aforementioned variability. Approach:Sixteen subjects performed a search task where the target saliency was varied while the EEG was recorded and the unrestrained eye movements were tracked. Based on the acquired data, it was estimated which of the items displayed were targets and which were distractors in the search task. Results: Target prediction was possible also when the stimulus saliencies were mixed. Information contained in EEG and eye tracking data was found to be complementary and neural signals were captured despite of the unrestricted eye movements. The classification algorithm was able to cope with the experimentally induced variable timing of neural activity related to target recognition. Significance: It was demonstrated how EEG and eye tracking data can provide implicit information about the relevance of items on the screen for potential use in online applications. PMID:26912993

  1. Visual saliency approach to anomaly detection in an image ensemble

    NASA Astrophysics Data System (ADS)

    Singh, Anurag; Pratt, Michael A.; Chu, Chee-Hung Henry

    2013-05-01

    Visual saliency is a bottom-up process that identifies those regions in an image that stand out from their surroundings. We oversegment an image as a collection of "super pixels" (SPs). Each SP is salient if it is different in color from all other SPs and if its most similar SPs are nearby. We test our method on image sequences collected by a vehicle. We consider an SP in a frame as salient if it stands out from all frames in a collection that consists of an ensemble of images from different road segments and a sequence of immediate past frames.

  2. Preserving visual saliency in image to sound substitution systems

    NASA Astrophysics Data System (ADS)

    Ancuti, Codruta O.; Ancuti, Cosmin; Bekaert, Philippe

    2009-02-01

    Color plays a significant role in the scene interpretation in terms of visual perception. Numerous visual substitution systems deal with grayscale images disregarding this information from original image. Visually percept color-based details often fade due to the grayscale conversion and that can mislead the overall comprehension of the considered scene. We present a decolorization method that considers color contrast and preserve color saliency after transformation. We exploit this model to enhance the perception of visually disable persons over the interpreted images by the substitution system. The results demonstrate that our enhance system is capable to improves the overall scene interpretation in comparison with similar substitution system.

  3. How Important Are Items on a Student Evaluation? A Study of Item Salience

    ERIC Educational Resources Information Center

    Hills, Stacey Barlow; Naegle, Natali; Bartkus, Kenneth R.

    2009-01-01

    Although student evaluations of teaching (SETs) have been the subject of numerous research studies, the salience of SET items to students has not been examined. In the present study, the authors surveyed 484 students from a large public university. The authors suggest that not all items are viewed equally and that measures of item salience can…

  4. Transitioning between Work and Family Roles as a Function of Boundary Flexibility and Role Salience

    ERIC Educational Resources Information Center

    Winkel, Doan E.; Clayton, Russell W.

    2010-01-01

    This study investigates the manner in which people separate their work and family roles and how they manage the boundaries of these two important roles. Specifically, we focus on how role flexibility and salience influence transitions between roles. Results indicate that the ability and willingness to flex a role boundary and role salience are…

  5. Mortality Salience of Birthdays on Day of Death in the Major Leagues

    ERIC Educational Resources Information Center

    Abel, Ernest L.; Kruger, Michael L.

    2009-01-01

    The authors assessed the relationship of mortality salience, as represented by birthdays, on the day of death. Preliminary studies considered the role of possible artifacts such as seasonality of birth and death, and time units for evaluation. On the basis of terror management theory's concept of "mortality salience," the authors hypothesized that…

  6. Peer Norm Salience for Academic Achievement, Prosocial Behavior, and Bullying: Implications for Adolescent School Experiences

    ERIC Educational Resources Information Center

    Dijkstra, Jan Kornelis; Gest, Scott D.

    2015-01-01

    This study investigated the significance of classroom-level norm salience, calculated as the within-classroom correlation between a behavior and peer-nominated popularity, by examining the extent to which norm salience moderated the relation of individual classroom behaviors (academic achievement, prosocial behavior, and bullying) with peer…

  7. "Always in My Face": An Exploration of Social Class Consciousness, Salience, and Values

    ERIC Educational Resources Information Center

    Martin, Georgianna L.

    2015-01-01

    This qualitative study explores social class consciousness, salience, and values of White, low-income, first-generation college students. Overall, participants minimized the salience of social class as an aspect of their identity with many of them expressing that they did not want their social class to define them. Although participants largely…

  8. Using Saliency Maps to Separate Competing Processes in Infant Visual Cognition

    ERIC Educational Resources Information Center

    Althaus, Nadja; Mareschal, Denis

    2012-01-01

    This article presents an eye-tracking study using a novel combination of visual saliency maps and "area-of-interest" analyses to explore online feature extraction during category learning in infants. Category learning in 12-month-olds (N = 22) involved a transition from looking at high-saliency image regions to looking at more informative, highly…

  9. The Marginality and Salience of Being Old: When Is Age Relevant?

    ERIC Educational Resources Information Center

    Ward, Russell A.

    1984-01-01

    Suggests that the social position and value of old age are normally of little importance in the personal lives of older people, partly because of the limited salience of age within their informal networks. Factors that heighten the salience of being old may reduce well being. (JAC)

  10. ION SWITCH

    DOEpatents

    Cook, B.

    1959-02-10

    An ion switch capable of transferring large magnitudes of power is described. An ion switch constructed in accordance with the invention includes a pair of spaced control electrodes disposed in a highly evacuated region for connection in a conventional circuit to control the passing of power therethrough. A controllable ionic conduction path is provided directiy between the control electrodes by a source unit to close the ion switch. Conventional power supply means are provided to trigger the source unit and control the magnitude, durations and pulse repetition rate of the aforementioned ionic conduction path.

  11. Spatiotemporal saliency model for small moving object detection in infrared videos

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Ning, Chen; Xu, Lizhong

    2015-03-01

    In this paper, a novel spatiotemporal saliency model based on three-dimensional Difference-of-Gaussians filters is proposed for small moving object detection in infrared videos. First, instead of utilizing the spatial Difference-of-Gaussians (DoG) filter which has been used to build saliency model for static images, we propose to extend the spatial DoG filter to construct three-dimensional (3D) Difference-of-Gaussians filters for measuring the center-surround difference in the spatiotemporal receptive field. Second, an effective spatiotemporal saliency model is generated based on these filters. This model provides a good basis for accurate and robust infrared small moving object detection. Experimental results show that the proposed saliency model consistently outperforms state-of-the-art saliency models for infrared moving object detection under various complex backgrounds.

  12. Fast Mode Decision in the HEVC Video Coding Standard by Exploiting Region with Dominated Motion and Saliency Features

    PubMed Central

    Podder, Pallab Kanti; Paul, Manoranjan; Murshed, Manzur

    2016-01-01

    The emerging High Efficiency Video Coding (HEVC) standard introduces a number of innovative and powerful coding tools to acquire better compression efficiency compared to its predecessor H.264. The encoding time complexities have also increased multiple times that is not suitable for realtime video coding applications. To address this limitation, this paper employs a novel coding strategy to reduce the time complexity in HEVC encoder by efficient selection of appropriate block-partitioning modes based on human visual features (HVF). The HVF in the proposed technique comprise with human visual attention modelling-based saliency feature and phase correlation-based motion features. The features are innovatively combined through a fusion process by developing a content-based adaptive weighted cost function to determine the region with dominated motion/saliency (RDMS)- based binary pattern for the current block. The generated binary pattern is then compared with a codebook of predefined binary pattern templates aligned to the HEVC recommended block-paritioning to estimate a subset of inter-prediction modes. Without exhaustive exploration of all modes available in the HEVC standard, only the selected subset of modes are motion estimated and motion compensated for a particular coding unit. The experimental evaluation reveals that the proposed technique notably down-scales the average computational time of the latest HEVC reference encoder by 34% while providing similar rate-distortion (RD) performance for a wide range of video sequences. PMID:26963813

  13. Acceleration switch

    DOEpatents

    Abbin, J.P. Jr.; Devaney, H.F.; Hake, L.W.

    1979-08-29

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  14. Acceleration switch

    DOEpatents

    Abbin, Jr., Joseph P.; Devaney, Howard F.; Hake, Lewis W.

    1982-08-17

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  15. Influence of Low-Level Stimulus Features, Task Dependent Factors, and Spatial Biases on Overt Visual Attention

    PubMed Central

    König, Peter

    2010-01-01

    Visual attention is thought to be driven by the interplay between low-level visual features and task dependent information content of local image regions, as well as by spatial viewing biases. Though dependent on experimental paradigms and model assumptions, this idea has given rise to varying claims that either bottom-up or top-down mechanisms dominate visual attention. To contribute toward a resolution of this discussion, here we quantify the influence of these factors and their relative importance in a set of classification tasks. Our stimuli consist of individual image patches (bubbles). For each bubble we derive three measures: a measure of salience based on low-level stimulus features, a measure of salience based on the task dependent information content derived from our subjects' classification responses and a measure of salience based on spatial viewing biases. Furthermore, we measure the empirical salience of each bubble based on our subjects' measured eye gazes thus characterizing the overt visual attention each bubble receives. A multivariate linear model relates the three salience measures to overt visual attention. It reveals that all three salience measures contribute significantly. The effect of spatial viewing biases is highest and rather constant in different tasks. The contribution of task dependent information is a close runner-up. Specifically, in a standardized task of judging facial expressions it scores highly. The contribution of low-level features is, on average, somewhat lower. However, in a prototypical search task, without an available template, it makes a strong contribution on par with the two other measures. Finally, the contributions of the three factors are only slightly redundant, and the semi-partial correlation coefficients are only slightly lower than the coefficients for full correlations. These data provide evidence that all three measures make significant and independent contributions and that none can be neglected in a model

  16. 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…

  17. Overspecification of color, pattern, and size: salience, absoluteness, and consistency

    PubMed Central

    Tarenskeen, Sammie; Broersma, Mirjam; Geurts, Bart

    2015-01-01

    The rates of overspecification of color, pattern, and size are compared, to investigate how salience and absoluteness contribute to the production of overspecification. Color and pattern are absolute and salient attributes, whereas size is relative and less salient. Additionally, a tendency toward consistent responses is assessed. Using a within-participants design, we find similar rates of color and pattern overspecification, which are both higher than the rate of size overspecification. Using a between-participants design, however, we find similar rates of pattern and size overspecification, which are both lower than the rate of color overspecification. This indicates that although many speakers are more likely to include color than pattern (probably because color is more salient), they may also treat pattern like color due to a tendency toward consistency. We find no increase in size overspecification when the salience of size is increased, suggesting that speakers are more likely to include absolute than relative attributes. However, we do find an increase in size overspecification when mentioning the attributes is triggered, which again shows that speakers tend to refer in a consistent manner, and that there are circumstances in which even size overspecification is frequently produced. PMID:26594190

  18. Information-theoretic model comparison unifies saliency metrics

    PubMed Central

    Kümmerer, Matthias; Wallis, Thomas S. A.; Bethge, Matthias

    2015-01-01

    Learning the properties of an image associated with human gaze placement is important both for understanding how biological systems explore the environment and for computer vision applications. There is a large literature on quantitative eye movement models that seeks to predict fixations from images (sometimes termed “saliency” prediction). A major problem known to the field is that existing model comparison metrics give inconsistent results, causing confusion. We argue that the primary reason for these inconsistencies is because different metrics and models use different definitions of what a “saliency map” entails. For example, some metrics expect a model to account for image-independent central fixation bias whereas others will penalize a model that does. Here we bring saliency evaluation into the domain of information by framing fixation prediction models probabilistically and calculating information gain. We jointly optimize the scale, the center bias, and spatial blurring of all models within this framework. Evaluating existing metrics on these rephrased models produces almost perfect agreement in model rankings across the metrics. Model performance is separated from center bias and spatial blurring, avoiding the confounding of these factors in model comparison. We additionally provide a method to show where and how models fail to capture information in the fixations on the pixel level. These methods are readily extended to spatiotemporal models of fixation scanpaths, and we provide a software package to facilitate their use. PMID:26655340

  19. Autonomous color theme extraction from images using saliency

    NASA Astrophysics Data System (ADS)

    Jahanian, Ali; Vishwanathan, S. V. N.; Allebach, Jan P.

    2015-03-01

    Color theme (palette) is a collection of color swatches for representing or describing colors in a visual design or an image. Color palettes have broad applications such as serving as means in automatic/semi-automatic design of visual media, as measures in quantifying aesthetics of visual design, and as metrics in image retrieval, image enhancement, and color semantics. In this paper, we suggest an autonomous mechanism for extracting color palettes from an image. Our method is simple and fast, and it works on the notion of visual saliency. By using visual saliency, we extract the fine colors appearing in the foreground along with the various colors in the background regions of an image. Our method accounts for defining different numbers of colors in the palette as well as presenting the proportion of each color according to its visual conspicuity in a given image. This flexibility supports an interactive color palette which may facilitate the designer's color design task. As an application, we present how our extracted color palettes can be utilized as a color similarity metric to enhance the current color semantic based image retrieval techniques.

  20. Scalable mobile image retrieval by exploring contextual saliency.

    PubMed

    Yang, Xiyu; Qian, Xueming; Xue, Yao

    2015-06-01

    Nowadays, it is very convenient to capture photos by a smart phone. As using, the smart phone is a convenient way to share what users experienced anytime and anywhere through social networks, it is very possible that we capture multiple photos to make sure the content is well photographed. In this paper, an effective scalable mobile image retrieval approach is proposed by exploring contextual salient information for the input query image. Our goal is to explore the high-level semantic information of an image by finding the contextual saliency from multiple relevant photos rather than solely using the input image. Thus, the proposed mobile image retrieval approach first determines the relevant photos according to visual similarity, then mines salient features by exploring contextual saliency from multiple relevant images, and finally determines contributions of salient features for scalable retrieval. Compared with the existing mobile-based image retrieval approaches, our approach requires less bandwidth and has better retrieval performance. We can carry out retrieval with <200-B data, which is <5% of existing approaches. Most importantly, when the bandwidth is limited, we can rank the transmitted features according to their contributions to retrieval. Experimental results show the effectiveness of the proposed approach. PMID:25775488

  1. Reward positivity: Reward prediction error or salience prediction error?

    PubMed

    Heydari, Sepideh; Holroyd, Clay B

    2016-08-01

    The reward positivity is a component of the human ERP elicited by feedback stimuli in trial-and-error learning and guessing tasks. A prominent theory holds that the reward positivity reflects a reward prediction error signal that is sensitive to outcome valence, being larger for unexpected positive events relative to unexpected negative events (Holroyd & Coles, 2002). Although the theory has found substantial empirical support, most of these studies have utilized either monetary or performance feedback to test the hypothesis. However, in apparent contradiction to the theory, a recent study found that unexpected physical punishments also elicit the reward positivity (Talmi, Atkinson, & El-Deredy, 2013). The authors of this report argued that the reward positivity reflects a salience prediction error rather than a reward prediction error. To investigate this finding further, in the present study participants navigated a virtual T maze and received feedback on each trial under two conditions. In a reward condition, the feedback indicated that they would either receive a monetary reward or not and in a punishment condition the feedback indicated that they would receive a small shock or not. We found that the feedback stimuli elicited a typical reward positivity in the reward condition and an apparently delayed reward positivity in the punishment condition. Importantly, this signal was more positive to the stimuli that predicted the omission of a possible punishment relative to stimuli that predicted a forthcoming punishment, which is inconsistent with the salience hypothesis. PMID:27184070

  2. An evaluation of attention models for use in SLAM

    NASA Astrophysics Data System (ADS)

    Dodge, Samuel; Karam, Lina

    2013-12-01

    In this paper we study the application of visual saliency models for the simultaneous localization and mapping (SLAM) problem. We consider visual SLAM, where the location of the camera and a map of the environment can be generated using images from a single moving camera. In visual SLAM, the interest point detector is of key importance. This detector must be invariant to certain image transformations so that features can be matched across di erent frames. Recent work has used a model of human visual attention to detect interest points, however it is unclear as to what is the best attention model for this purpose. To this aim, we compare the performance of interest points from four saliency models (Itti, GBVS, RARE, and AWS) with the performance of four traditional interest point detectors (Harris, Shi-Tomasi, SIFT, and FAST). We evaluate these detectors under several di erent types of image transformation and nd that the Itti saliency model, in general, achieves the best performance in terms of keypoint repeatability.

  3. Spatial attention and neglect: parietal, frontal and cingulate contributions to the mental representation and attentional targeting of salient extrapersonal events.

    PubMed Central

    Mesulam, M M

    1999-01-01

    The syndrome of contralesional neglect reflects a lateralized disruption of spatial attention. In the human, the left hemisphere shifts attention predominantly in the contralateral hemispace and in a contraversive direction whereas the right hemisphere distributes attention more evenly, in both hemispaces and both directions. As a consequence of this asymmetry, severe contralesional neglect occurs almost exclusively after right hemisphere lesions. Patients with left neglect experience a loss of salience in the mental representation and conscious perception of the left side and display a reluctance to direct orientating and exploratory behaviours to the left. Neglect is distributed according to egocentric, allocentric, world-centred, and object-centred frames of reference. Neglected events can continue to exert an implicit influence on behaviour, indicating that the attentional filtering occurs at the level of an internalized representation rather than at the level of peripheral sensory input. The unilateral neglect syndrome is caused by a dysfunction of a large-scale neurocognitive network, the cortical epicentres of which are located in posterior parietal cortex, the frontal eye fields, and the cingulate gyrus. This network coordinates all aspects of spatial attention, regardless of the modality of input or output. It helps to compile a mental representation of extrapersonal events in terms of their motivational salience, and to generate 'kinetic strategies' so that the attentional focus can shift from one target to another. PMID:10466154

  4. The Yin and Yang of Sleep and Attention.

    PubMed

    Kirszenblat, Leonie; van Swinderen, Bruno

    2015-12-01

    Sleep is not a single state, but a complex set of brain processes that supports several physiological needs. Sleep deprivation is known to affect attention in many animals, suggesting that a key function of sleep is to regulate attention. Conversely, tasks that require more attention drive sleep need and sleep intensity. Attention involves the ability to filter incoming stimuli based on their relative salience, and this is likely to require coordinated synaptic activity across the brain. This capacity may have only become possible with the evolution of related neural mechanisms that support two key sleep functions: stimulus suppression and synaptic plasticity. We argue here that sleep and attention may have coevolved as brain states that regulate each other. PMID:26602764

  5. Correspondences among pupillary dilation response, subjective salience of sounds, and loudness.

    PubMed

    Liao, Hsin-I; Kidani, Shunsuke; Yoneya, Makoto; Kashino, Makio; Furukawa, Shigeto

    2016-04-01

    A pupillary dilation response is known to be evoked by salient deviant or contrast auditory stimuli, but so far a direct link between it and subjective salience has been lacking. In two experiments, participants listened to various environmental sounds while their pupillary responses were recorded. In separate sessions, participants performed subjective pairwise-comparison tasks on the sounds with respect to their salience, loudness, vigorousness, preference, beauty, annoyance, and hardness. The pairwise-comparison data were converted to ratings on the Thurstone scale. The results showed a close link between subjective judgments of salience and loudness. The pupil dilated in response to the sound presentations, regardless of sound type. Most importantly, this pupillary dilation response to an auditory stimulus positively correlated with the subjective salience, as well as the loudness, of the sounds (Exp. 1). When the loudnesses of the sounds were identical, the pupil responses to each sound were similar and were not correlated with the subjective judgments of salience or loudness (Exp. 2). This finding was further confirmed by analyses based on individual stimulus pairs and participants. In Experiment 3, when salience and loudness were manipulated by systematically changing the sound pressure level and acoustic characteristics, the pupillary dilation response reflected the changes in both manipulated factors. A regression analysis showed a nearly perfect linear correlation between the pupillary dilation response and loudness. The overall results suggest that the pupillary dilation response reflects the subjective salience of sounds, which is defined, or is heavily influenced, by loudness. PMID:26163191

  6. Work-family conflict, work- and family-role salience, and women's well-being.

    PubMed

    Noor, Noraini M

    2004-08-01

    The author considered both the direct effect and the moderator effect of role salience in the stress-strain relationship. In contrast to previous studies that have examined the effects of salience on well-being within specific social roles, the present study focused on the work-family interface. From a sample of 147 employed English women with children, the present results of the regression analyses showed that both effects are possible, depending on the outcome measures used. The author observed a direct effect of role salience in the prediction of job satisfaction; work salience was positively related to job satisfaction, over and above the main-effect terms of work-interfering-with-family (WIF) conflict and family-interfering-with-work (FIW) conflict. In contrast, the author found a moderator effect of role salience and conflict for symptoms of psychological distress. However, contrary to predictions, the author found that work salience exacerbated the negative impact of WIF conflict, rather than FIW conflict, on well-being. The author discussed these results in relation to the literature on work-family conflict, role salience, and the issue of stress-strain specificity. PMID:15279329

  7. Detection of Bird Nests during Mechanical Weeding by Incremental Background Modeling and Visual Saliency

    PubMed Central

    Steen, Kim Arild; Therkildsen, Ole Roland; Green, Ole; Karstoft, Henrik

    2015-01-01

    Mechanical weeding is an important tool in organic farming. However, the use of mechanical weeding in conventional agriculture is increasing, due to public demands to lower the use of pesticides and an increased number of pesticide-resistant weeds. Ground nesting birds are highly susceptible to farming operations, like mechanical weeding, which may destroy the nests and reduce the survival of chicks and incubating females. This problem has limited focus within agricultural engineering. However, when the number of machines increases, destruction of nests will have an impact on various species. It is therefore necessary to explore and develop new technology in order to avoid these negative ethical consequences. This paper presents a vision-based approach to automated ground nest detection. The algorithm is based on the fusion of visual saliency, which mimics human attention, and incremental background modeling, which enables foreground detection with moving cameras. The algorithm achieves a good detection rate, as it detects 28 of 30 nests at an average distance of 3.8 m, with a true positive rate of 0.75. PMID:25738766

  8. What catches a radiologist's eye? A comprehensive comparison of feature types for saliency prediction

    NASA Astrophysics Data System (ADS)

    Alzubaidi, Mohammad; Balasubramanian, Vineeth; Patel, Ameet; Panchanathan, Sethuraman; Black, John A., Jr.

    2010-03-01

    Experienced radiologists are in short supply, and are sometimes called upon to read many images in a short amount of time. This leaves them with a limited amount of time to read images, and can lead to fatigue and stress which can be sources of error, as they overlook subtle abnormalities that they otherwise might not miss. Another factor in error rates is called satisfaction of search, where a radiologist misses a second (typically subtle) abnormality after finding the first. These types of errors are due primarily to a lack of attention to an important region of the image during the search. In this paper we discuss the use of eye tracker technology, in combination with image analysis and machine learning techniques, to learn what types of features catch the eye experienced radiologists when reading chest x-rays for diagnostic purposes, and to then use that information to produce saliency maps that predict what regions of each image might be most interesting to radiologists. We found that, out of 13 popular features types that are widely extracted to characterize images, 4 are particularly useful for this task: (1) Localized Edge Orientation Histograms (2) Haar Wavelets, (3) Gabor Filters, and (4) Steerable Filters.

  9. Optical switch

    DOEpatents

    Reedy, Robert P.

    1987-01-01

    An optical switching device (10) is provided whereby light from a first glass fiber (16) or a second glass fiber (14) may be selectively transmitted into a third glass fiber (18). Each glass fiber is provided with a focusing and collimating lens system (26, 28, 30). In one mode of operation, light from the first glass fiber (16) is reflected by a planar mirror (36) into the third glass fiber (18). In another mode of operation, light from the second glass fiber (14) passes directly into the third glass fiber (18). The planar mirror (36) is attached to a rotatable table (32) which is rotated to provide the optical switching.

  10. Incentive salience attribution under reward uncertainty: A Pavlovian model.

    PubMed

    Anselme, Patrick

    2015-02-01

    There is a vast literature on the behavioural effects of partial reinforcement in Pavlovian conditioning. Compared with animals receiving continuous reinforcement, partially rewarded animals typically show (a) a slower development of the conditioned response (CR) early in training and (b) a higher asymptotic level of the CR later in training. This phenomenon is known as the partial reinforcement acquisition effect (PRAE). Learning models of Pavlovian conditioning fail to account for it. In accordance with the incentive salience hypothesis, it is here argued that incentive motivation (or 'wanting') plays a more direct role in controlling behaviour than does learning, and reward uncertainty is shown to have an excitatory effect on incentive motivation. The psychological origin of that effect is discussed and a computational model integrating this new interpretation is developed. Many features of CRs under partial reinforcement emerge from this model. PMID:25444780

  11. Increasing the perceptual salience of relationships in parallel coordinate plots

    PubMed Central

    Harter, Jonathan M.; Wu, Xunlei; Alabi, Oluwafemi S.; Phadke, Madhura; Pinto, Lifford; Dougherty, Daniel; Petersen, Hannah; Bass, Steffen; Taylor, Russell M.

    2012-01-01

    We present three extensions to parallel coordinates that increase the perceptual salience of relationships between axes in multivariate data sets: (1) luminance modulation maintains the ability to preattentively detect patterns in the presence of overplotting, (2) adding a one-vs.-all variable display highlights relationships between one variable and all others, and (3) adding a scatter plot within the parallel-coordinates display preattentively highlights clusters and spatial layouts without strongly interfering with the parallel-coordinates display. These techniques can be combined with one another and with existing extensions to parallel coordinates, and two of them generalize beyond cases with known-important axes. We applied these techniques to two real-world data sets (relativistic heavy-ion collision hydrodynamics and weather observations with statistical principal component analysis) as well as the popular car data set. We present relationships discovered in the data sets using these methods. PMID:23145217

  12. Mortality salience increases defensive distancing from people with terminal cancer.

    PubMed

    Smith, Lauren M; Kasser, Tim

    2014-01-01

    Based on principles of terror management theory, the authors hypothesized that participants would distance more from a target person with terminal cancer than from a target with arthritis, and that this effect would be stronger following mortality salience. In Study 1, adults rated how similar their personalities were to a target person; in Study 2, participants arranged two chairs in preparation for meeting the target person. Both studies found that distancing from the person with terminal cancer increased after participants wrote about their own death (vs. giving a speech). Thus, death anxiety may explain why people avoid close contact with terminally ill people; further analyses suggest that gender and self-esteem may also influence such distancing from the terminally ill. PMID:24521045

  13. Race Salience and Essentialist Thinking in Racial Stereotype Development

    PubMed Central

    Pauker, Kristin; Ambady, Nalini; Apfelbaum, Evan P.

    2010-01-01

    The authors explored the emergence and antecedents of racial stereotyping in 89 children ages 3–10 years. Children completed a number of matching and sorting tasks, including a measure designed to assess their knowledge and application of both positive and negative in-group and out-group stereotypes. Results indicate that children start to apply stereotypes to the out-group starting around 6 years of age. Controlling for a number of factors, two predictors contributed significantly towards uniquely explaining the use of these stereotypes: race salience (i.e., seeing and organizing by race) and essentialist thinking (i.e., believing that race cannot change). These results provide insight into how and when real-world interventions aimed at altering the acquisition of racial stereotypes may be implemented. PMID:21077865

  14. Salience of physical appearance characteristics among young women in Thailand.

    PubMed

    Rongmuang, Daravan; Corte, Colleen; McCreary, Linda L; Park, Chang G; Miller, Arlene; Gallo, Agatha

    2011-09-01

    Our aim in the present study was to identify key components of physical appearance among young Thai women. Free listings, focus groups and pile sorting were used. One-hundred twenty young women generated 78 unique physical appearance characteristics. Ninety-four nursing students validated these characteristics in focus groups and then sorted them into piles that reflected separate domains of physical appearance and labeled them. Salience analysis revealed that facial appearance (e.g., bright facial skin, high nose bridge, big eyes) was the most important domain, followed by body weight and shape, skin color and texture, hair (color, texture, length), and 'other' physical appearance (e.g., slender neck, slim fingers). This is the first study to identify aspects of physical appearance that are most salient to young Thai women and that may differ from women in other cultural contexts. These findings could be used to develop culturally grounded measures of physical appearance in Thai women. PMID:21768001

  15. Local feature saliency classifier for real-time intrusion monitoring

    NASA Astrophysics Data System (ADS)

    Buch, Norbert; Velastin, Sergio A.

    2014-07-01

    We propose a texture saliency classifier to detect people in a video frame by identifying salient texture regions. The image is classified into foreground and background in real time. No temporal image information is used during the classification. The system is used for the task of detecting people entering a sterile zone, which is a common scenario for visual surveillance. Testing is performed on the Imagery Library for Intelligent Detection Systems sterile zone benchmark dataset of the United Kingdom's Home Office. The basic classifier is extended by fusing its output with simple motion information, which significantly outperforms standard motion tracking. A lower detection time can be achieved by combining texture classification with Kalman filtering. The fusion approach running at 10 fps gives the highest result of F1=0.92 for the 24-h test dataset. The paper concludes with a detailed analysis of the computation time required for the different parts of the algorithm.

  16. Switching Transistor

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Westinghouse Electric Corporation's D60T transistors are used primarily as switching devices for controlling high power in electrical circuits. It enables reduction in the number and size of circuit components and promotes more efficient use of energy. Wide range of application from a popcorn popper to a radio frequency generator for solar cell production.

  17. Perceptive visual attention model based on depth information for free viewpoint video rendering

    NASA Astrophysics Data System (ADS)

    Park, Min-Chul; Son, Jung-Young

    2009-05-01

    How to detect meaningful video representation becomes an interesting problem in various research communities. Visual attention system detects "Region of Interesting" from input video sequence. Generally the attended regions correspond to visually prominent object in the image in video sequence. In this paper, we have improved previous approaches using spatiotemporal attention modules. We proposed to make use of 3D depth map information in addition to spatiotemporal features. Therefore, the proposed method can compensate typical spatiotemporal saliency approaches for their inaccuracy. Motion is important cue when we derive temporal saliency. On the other hand noise information that deteriorates accuracy of temporal saliency is also obtained during the computation. To obtain the saliency map with more accuracy the noise should be removed. In order to settle down the problem, we used the result of psychological studies on "double opponent receptive field" and "noise filtration" in Middle Temporal area. We also applied "FlagMap" on each frame to prevent "Flickering" of global-area noise. As a result of this consideration, our system can detect the salient regions in the image with higher accuracy while removing noise effectively. It has been applied to several image sequences as a result the proposed method can describe the salient regions with more accuracy in another higher domain than the typical approach does. The obtained result can be applied to generate a spontaneous viewpoint offered by the system itself for "3-D imaging projector" or 3-DTV.

  18. Social relevance drives viewing behavior independent of low-level salience in rhesus macaques.

    PubMed

    Solyst, James A; Buffalo, Elizabeth A

    2014-01-01

    Quantifying attention to social stimuli during the viewing of complex social scenes with eye tracking has proven to be a sensitive method in the diagnosis of autism spectrum disorders years before average clinical diagnosis. Rhesus macaques provide an ideal model for understanding the mechanisms underlying social viewing behavior, but to date no comparable behavioral task has been developed for use in monkeys. Using a novel scene-viewing task, we monitored the gaze of three rhesus macaques while they freely viewed well-controlled composed social scenes and analyzed the time spent viewing objects and monkeys. In each of six behavioral sessions, monkeys viewed a set of 90 images (540 unique scenes) with each image presented twice. In two-thirds of the repeated scenes, either a monkey or an object was replaced with a novel item (manipulated scenes). When viewing a repeated scene, monkeys made longer fixations and shorter saccades, shifting from a rapid orienting to global scene contents to a more local analysis of fewer items. In addition to this repetition effect, in manipulated scenes, monkeys demonstrated robust memory by spending more time viewing the replaced items. By analyzing attention to specific scene content, we found that monkeys strongly preferred to view conspecifics and that this was not related to their salience in terms of low-level image features. A model-free analysis of viewing statistics found that monkeys that were viewed earlier and longer had direct gaze and redder sex skin around their face and rump, two important visual social cues. These data provide a quantification of viewing strategy, memory and social preferences in rhesus macaques viewing complex social scenes, and they provide an important baseline with which to compare to the effects of therapeutics aimed at enhancing social cognition. PMID:25414633

  19. On the Temporal Relation of Top-Down and Bottom-Up Mechanisms during Guidance of Attention

    ERIC Educational Resources Information Center

    Wykowska, Agnieszka; Schubo, Anna

    2010-01-01

    Two mechanisms are said to be responsible for guiding focal attention in visual selection: bottom-up, saliency-driven capture and top-down control. These mechanisms were examined with a paradigm that combined a visual search task with postdisplay probe detection. Two SOAs between the search display and probe onsets were introduced to investigate…

  20. Aspects of love: the effect of mortality salience and attachment style on romantic beliefs.

    PubMed

    Smith, Rebecca; Massey, Emma

    Two studies are reported which explore romance as a means of terror management for participants with secure and insecure attachment styles. Mikulincer and Florian (2000) have shown that while mortality salience increases the desire for intimacy in securely attached individuals, the insecurely attached use cultural world views rather than close relationships to cope with fear of death. Study 1 used the romantic belief scale to compare the effects of attachment style and mortality salience on the cultural aspects of close relationships and showed that the only the insecurely attached were more romantic following mortality salience. Study 2 replicated this effect and demonstrated that this difference was not simply due to lower self-esteem in the insecurely attached. The additional inclusion of the Relationship assessment questionnaire failed to provide any evidence that the securely attached were affected by the mortality salience manipulation, even on a more interpersonal measure. PMID:23472322

  1. Spectral residual method of saliency detection based on the two-dimensional fractional Fourier transform domain

    NASA Astrophysics Data System (ADS)

    Tian, Jiangxue; Qi, Lin; Wang, Yaxing

    2015-12-01

    As one of classic methods of frequency domain based saliency detection, Spectral residual (SR) method has shown several advantages. However, it usually produces higher saliency values at object edges instead of generating maps that uniformly cover the whole object, which results from failing to exploit all the spatial frequency content of the original image. The Two-Dimensional Fractional Fourier transform (2D-FRFT) is a generalized form of the traditional Fourier Transform (FT) which can abstract more meaningful information of the image under certain conditions. Based on this property, we propose a new method which detects the salient region based on 2D-FRFT domain. Moreover, we also use Hough transform detection and a band-pass filter to refine the saliency map. We conduct experiments on a common used dataset: MSRA. The proposed method is compared with several other saliency detection methods and shown to achieve superior result.

  2. The research and application of visual saliency and adaptive support vector machine in target tracking field.

    PubMed

    Chen, Yuantao; Xu, Weihong; Kuang, Fangjun; Gao, Shangbing

    2013-01-01

    The efficient target tracking algorithm researches have become current research focus of intelligent robots. The main problems of target tracking process in mobile robot face environmental uncertainty. They are very difficult to estimate the target states, illumination change, target shape changes, complex backgrounds, and other factors and all affect the occlusion in tracking robustness. To further improve the target tracking's accuracy and reliability, we present a novel target tracking algorithm to use visual saliency and adaptive support vector machine (ASVM). Furthermore, the paper's algorithm has been based on the mixture saliency of image features. These features include color, brightness, and sport feature. The execution process used visual saliency features and those common characteristics have been expressed as the target's saliency. Numerous experiments demonstrate the effectiveness and timeliness of the proposed target tracking algorithm in video sequences where the target objects undergo large changes in pose, scale, and illumination. PMID:24363779

  3. Using saliency maps to separate competing processes in infant visual cognition.

    PubMed

    Althaus, Nadja; Mareschal, Denis

    2012-01-01

    This article presents an eye-tracking study using a novel combination of visual saliency maps and "area-of-interest" analyses to explore online feature extraction during category learning in infants. Category learning in 12-month-olds (N = 22) involved a transition from looking at high-saliency image regions to looking at more informative, highly variable object parts. In contrast, 4-month-olds (N = 27) exhibited a different pattern displaying a similar decreasing impact of saliency accompanied by a steady focus on the object's center, indicating that targeted feature extraction during category learning develops across the 1st year of life. These results illustrate how the effects of lower and higher level processes may be disentangled using a combined saliency map and area-of-interest analysis. PMID:22533474

  4. The Causal Ordering of Prominence and Salience in Identity Theory: An Empirical Examination

    PubMed Central

    Brenner, Philip S.; Serpe, Richard T.; Stryker, Sheldon

    2016-01-01

    Identity theory invokes two distinct but related concepts, identity salience and prominence, to explain how the organization of identities that make up the self impacts the probability that a given identity is situationally enacted. However, much extant research has failed to clearly distinguish between salience and prominence, and their empirical relationship has not been adequately investigated, impeding a solid understanding of the significance and role of each in a general theory of the self. This study examines their causal ordering using three waves of panel data from 48 universities focusing on respondents’ identities as science students. Analyses strongly support a causal ordering from prominence to salience. We provide theoretical and empirical grounds to justify this ordering while acknowledging potential variation in its strength across identities. Finally, we offer recommendations about the use of prominence and salience when measures of one or both are available or when analyses use cross-sectional data. PMID:27284212

  5. Children's Location of a Point in Space: Effects of Dimensionality and Salience of Frame of Reference.

    ERIC Educational Resources Information Center

    Allen, Deborah A.; Hennessey, Steve, Jr.

    1980-01-01

    Examines the effects of dimensionality and salience of frame of reference on children's location of a point in space. Subjects were eight boys and eight girls from each of first, second and third grades. (CM)

  6. Amygdala activation to fearful faces under attentional load.

    PubMed

    Mothes-Lasch, Martin; Mentzel, Hans-Joachim; Miltner, Wolfgang H R; Straube, Thomas

    2013-01-15

    While some functional imaging studies suggested an automatic activation of the amygdala to fearful vs. neutral faces, recent studies showed the absence of amygdala activation to fearful faces under high attentional load induced by distracting tasks. The present fMRI study investigated whether this outcome can be modulated by changing the saliency of the eyes of fearful faces. Subjects had to solve a high perceptual load task while they were presented either with normal faces (Exp. 1) or with normal faces intermixed with faces, in which pupil and iris of eyes were erased to increase the saliency of the normal eyes (Exp. 2). There was no differential amygdala activation to fearful versus neutral faces under standard conditions without any manipulation of the faces (Exp. 1). In contrast to this outcome, Experiment 2 led to differential amygdala activation to the normal but not to the manipulated fearful vs. neutral faces. These findings propose a concept of relative automaticity of the activation of the amygdala. The activation depends on available cognitive resources and on the saliency of specific parts of fearful faces. PMID:23018121

  7. The role of the neural reward system in attention selection.

    PubMed

    Soder, Heather E; de Dios, Constanza; Potts, Geoffrey F

    2016-07-01

    The prefrontal cortex may play a role in attention selection using motivational information from the mesotelencephalic dopamine system, a neural system that responds to reward prediction violations. If so, neural indices of attention selection and reward prediction violation should have overlapping spatiotemporal distributions. Attention selection elicits a frontal event-related potential component around 200-300 ms, the frontal selection positivity. A component with similar spatiotemporal characteristics, the reward positivity is elicited in reward prediction designs to outcomes that are better than expected. The current study used dense sensor array recording in a sample of 41 participants performing visual oddball (attention) and a reward prediction 'slot machine-like' design to compare the spatiotemporal distributions of the frontal selection positivity and the reward positivity. The components did not differ in their peak latencies and had overlapping scalp topographies, supporting the hypothesis that these positivities represent attachment of incentive salience to perceptual representations in the prefrontal cortex. PMID:27232519

  8. Mechanisms of Selective Attention in Generalized Anxiety Disorder

    PubMed Central

    Yiend, Jenny; Mathews, Andrew; Burns, Tom; Dutton, Kevin; Fernández-Martín, Andrés; Georgiou, George A.; Luckie, Michael; Rose, Alexandra; Russo, Riccardo; Fox, Elaine

    2015-01-01

    A well-established literature has identified different selective attentional orienting mechanisms underlying anxiety-related attentional bias, such as engagement and disengagement of attention. These mechanisms are thought to contribute to the onset and maintenance of anxiety disorders. However, conclusions to date have relied heavily on experimental work from subclinical samples. We therefore investigated individuals with diagnosed generalized anxiety disorder (GAD), healthy volunteers, and individuals with high trait anxiety (but not meeting GAD diagnostic criteria). Across two experiments we found faster disengagement from negative (angry and fearful) faces in GAD groups, an effect opposite to that expected on the basis of the subclinical literature. Together these data challenge current assumptions that we can generalize, to those with GAD, the pattern of selective attentional orienting to threat found in subclinical groups. We suggest a decisive two-stage experiment identifying stimuli of primary salience in GAD, then using these to reexamine orienting mechanisms across groups. PMID:26504675

  9. Aberrant Salience, Self-Concept Clarity, and Interview-Rated Psychotic-Like Experiences

    PubMed Central

    Cicero, David C.; Docherty, Anna R.; Becker, Theresa M.; Martin, Elizabeth A.; Kerns, John G.

    2014-01-01

    Many social-cognitive models of psychotic-like symptoms posit a role for self-concept and aberrant salience. Previous work has shown that the interaction between aberrant salience and self-concept clarity is associated with self-reported psychotic-like experiences. In the current research with two structured interviews, the interaction between aberrant salience and self-concept clarity was found to be associated withinterview-rated psychotic-like experiences. The interaction was associated withpsychotic-like experiences composite scores, delusional ideation, grandiosity, and perceptual anomalies. In all cases, self-concept clarity was negatively associated with psychotic-like experiences at high levels of aberrant salience, but unassociated with psychotic-like experiences at low levels of aberrant salience. The interaction was specific to positive psychotic-like experiences and not present for negative or disorganized ratings. The interaction was not mediated by self-esteem levels. These results provide further evidence that aberrant salience and self-concept clarity play an important role in the generation of psychotic-like experiences. PMID:25102085

  10. Aberrant salience, self-concept clarity, and interview-rated psychotic-like experiences.

    PubMed

    Cicero, David C; Docherty, Anna R; Becker, Theresa M; Martin, Elizabeth A; Kerns, John G

    2015-02-01

    Many social-cognitive models of psychotic-like symptoms posit a role for self-concept and aberrant salience. Previous work has shown that the interaction between aberrant salience and self-concept clarity is associated with self-reported psychotic-like experiences. In the current research with two structured interviews, the interaction between aberrant salience and self-concept clarity was found to be associated with interview-rated psychotic-like experiences. The interaction was associated with psychotic-like experiences composite scores, delusional ideation, grandiosity, and perceptual anomalies. In all cases, self-concept clarity was negatively associated with psychotic-like experiences at high levels of aberrant salience, but unassociated with psychotic-like experiences at low levels of aberrant salience. The interaction was specific to positive psychotic-like experiences and not present for negative or disorganized ratings. The interaction was not mediated by self-esteem levels. These results provide further evidence that aberrant salience and self-concept clarity play an important role in the generation of psychotic-like experiences. PMID:25102085

  11. The Motivational Salience of Faces Is Related to Both Their Valence and Dominance

    PubMed Central

    Wang, Hongyi; Hahn, Amanda C.; DeBruine, Lisa M.; Jones, Benedict C.

    2016-01-01

    Both behavioral and neural measures of the motivational salience of faces are positively correlated with their physical attractiveness. Whether physical characteristics other than attractiveness contribute to the motivational salience of faces is not known, however. Research with male macaques recently showed that more dominant macaques’ faces hold greater motivational salience. Here we investigated whether dominance also contributes to the motivational salience of faces in human participants. Principal component analysis of third-party ratings of faces for multiple traits revealed two orthogonal components. The first component (“valence”) was highly correlated with rated trustworthiness and attractiveness. The second component (“dominance”) was highly correlated with rated dominance and aggressiveness. Importantly, both components were positively and independently related to the motivational salience of faces, as assessed from responses on a standard key-press task. These results show that at least two dissociable components underpin the motivational salience of faces in humans and present new evidence for similarities in how humans and non-human primates respond to facial cues of dominance. PMID:27513859

  12. DeepSaliency: Multi-Task Deep Neural Network Model for Salient Object Detection.

    PubMed

    Li, Xi; Zhao, Liming; Wei, Lina; Yang, Ming-Hsuan; Wu, Fei; Zhuang, Yueting; Ling, Haibin; Wang, Jingdong

    2016-08-01

    A key problem in salient object detection is how to effectively model the semantic properties of salient objects in a data-driven manner. In this paper, we propose a multi-task deep saliency model based on a fully convolutional neural network with global input (whole raw images) and global output (whole saliency maps). In principle, the proposed saliency model takes a data-driven strategy for encoding the underlying saliency prior information, and then sets up a multi-task learning scheme for exploring the intrinsic correlations between saliency detection and semantic image segmentation. Through collaborative feature learning from such two correlated tasks, the shared fully convolutional layers produce effective features for object perception. Moreover, it is capable of capturing the semantic information on salient objects across different levels using the fully convolutional layers, which investigate the feature-sharing properties of salient object detection with a great reduction of feature redundancy. Finally, we present a graph Laplacian regularized nonlinear regression model for saliency refinement. Experimental results demonstrate the effectiveness of our approach in comparison with the state-of-the-art approaches. PMID:27305676

  13. DeepSaliency: Multi-Task Deep Neural Network Model for Salient Object Detection

    NASA Astrophysics Data System (ADS)

    Li, Xi; Zhao, Liming; Wei, Lina; Yang, Ming-Hsuan; Wu, Fei; Zhuang, Yueting; Ling, Haibin; Wang, Jingdong

    2016-08-01

    A key problem in salient object detection is how to effectively model the semantic properties of salient objects in a data-driven manner. In this paper, we propose a multi-task deep saliency model based on a fully convolutional neural network (FCNN) with global input (whole raw images) and global output (whole saliency maps). In principle, the proposed saliency model takes a data-driven strategy for encoding the underlying saliency prior information, and then sets up a multi-task learning scheme for exploring the intrinsic correlations between saliency detection and semantic image segmentation. Through collaborative feature learning from such two correlated tasks, the shared fully convolutional layers produce effective features for object perception. Moreover, it is capable of capturing the semantic information on salient objects across different levels using the fully convolutional layers, which investigate the feature-sharing properties of salient object detection with great feature redundancy reduction. Finally, we present a graph Laplacian regularized nonlinear regression model for saliency refinement. Experimental results demonstrate the effectiveness of our approach in comparison with the state-of-the-art approaches.

  14. The Motivational Salience of Faces Is Related to Both Their Valence and Dominance.

    PubMed

    Wang, Hongyi; Hahn, Amanda C; DeBruine, Lisa M; Jones, Benedict C

    2016-01-01

    Both behavioral and neural measures of the motivational salience of faces are positively correlated with their physical attractiveness. Whether physical characteristics other than attractiveness contribute to the motivational salience of faces is not known, however. Research with male macaques recently showed that more dominant macaques' faces hold greater motivational salience. Here we investigated whether dominance also contributes to the motivational salience of faces in human participants. Principal component analysis of third-party ratings of faces for multiple traits revealed two orthogonal components. The first component ("valence") was highly correlated with rated trustworthiness and attractiveness. The second component ("dominance") was highly correlated with rated dominance and aggressiveness. Importantly, both components were positively and independently related to the motivational salience of faces, as assessed from responses on a standard key-press task. These results show that at least two dissociable components underpin the motivational salience of faces in humans and present new evidence for similarities in how humans and non-human primates respond to facial cues of dominance. PMID:27513859

  15. On computational modeling of visual saliency: Examining what's right, and what's left.

    PubMed

    Bruce, Neil D B; Wloka, Calden; Frosst, Nick; Rahman, Shafin; Tsotsos, John K

    2015-11-01

    In the past decade, a large number of computational models of visual saliency have been proposed. Recently a number of comprehensive benchmark studies have been presented, with the goal of assessing the performance landscape of saliency models under varying conditions. This has been accomplished by considering fixation data, annotated image regions, and stimulus patterns inspired by psychophysics. In this paper, we present a high-level examination of challenges in computational modeling of visual saliency, with a heavy emphasis on human vision and neural computation. This includes careful assessment of different metrics for performance of visual saliency models, and identification of remaining difficulties in assessing model performance. We also consider the importance of a number of issues relevant to all saliency models including scale-space, the impact of border effects, and spatial or central bias. Additionally, we consider the biological plausibility of models in stepping away from exemplar input patterns towards a set of more general theoretical principles consistent with behavioral experiments. As a whole, this presentation establishes important obstacles that remain in visual saliency modeling, in addition to identifying a number of important avenues for further investigation. PMID:25666489

  16. How visual attention is modified by disparities and textures changes?

    NASA Astrophysics Data System (ADS)

    Khaustova, Dar'ya; Fournier, Jérome; Wyckens, Emmanuel; Le Meur, Olivier

    2013-03-01

    The 3D image/video quality of experience is a multidimensional concept that depends on 2D image quality, depth quantity and visual comfort. The relationship between these parameters is not yet clearly defined. From this perspective, we aim to understand how texture complexity, depth quantity and visual comfort influence the way people observe 3D content in comparison with 2D. Six scenes with different structural parameters were generated using Blender software. For these six scenes, the following parameters were modified: texture complexity and the amount of depth changing the camera baseline and the convergence distance at the shooting side. Our study was conducted using an eye-tracker and a 3DTV display. During the eye-tracking experiment, each observer freely examined images with different depth levels and texture complexities. To avoid memory bias, we ensured that each observer had only seen scene content once. Collected fixation data were used to build saliency maps and to analyze differences between 2D and 3D conditions. Our results show that the introduction of disparity shortened saccade length; however fixation durations remained unaffected. An analysis of the saliency maps did not reveal any differences between 2D and 3D conditions for the viewing duration of 20 s. When the whole period was divided into smaller intervals, we found that for the first 4 s the introduced disparity was conducive to the section of saliency regions. However, this contribution is quite minimal if the correlation between saliency maps is analyzed. Nevertheless, we did not find that discomfort (comfort) had any influence on visual attention. We believe that existing metrics and methods are depth insensitive and do not reveal such differences. Based on the analysis of heat maps and paired t-tests of inter-observer visual congruency values we deduced that the selected areas of interest depend on texture complexities.

  17. Modification Of A Communication Switch In A Helicopter

    NASA Technical Reports Server (NTRS)

    Haworth, Loran; Szoboszlay, Zoltan; Shively, Robert; Bick, Frank J.

    1992-01-01

    Report describes preliminary study of modification of electronic circuitry connected to communication-channel-selecting switches in AH-1 Cobra helicopter. Switches in question are foot switch and cyclic thumb-wheel switch mounted on joystick flight control. Modification enables pilots and other crewmembers to select radio channels or intercommunication with less diversion of attention from flight control and other critical tasks. Intended to enhance safety and performance in critical situations.

  18. The impact of attentional, linguistic, and visual features during object naming.

    PubMed

    Clarke, Alasdair D F; Coco, Moreno I; Keller, Frank

    2013-01-01

    Object detection and identification are fundamental to human vision, and there is mounting evidence that objects guide the allocation of visual attention. However, the role of objects in tasks involving multiple modalities is less clear. To address this question, we investigate object naming, a task in which participants have to verbally identify objects they see in photorealistic scenes. We report an eye-tracking study that investigates which features (attentional, visual, and linguistic) influence object naming. We find that the amount of visual attention directed toward an object, its position and saliency, along with linguistic factors such as word frequency, animacy, and semantic proximity, significantly influence whether the object will be named or not. We then ask how features from different modalities are combined during naming, and find significant interactions between saliency and position, saliency and linguistic features, and attention and position. We conclude that when the cognitive system performs tasks such as object naming, it uses input from one modality to constraint or enhance the processing of other modalities, rather than processing each input modality independently. PMID:24379792

  19. The impact of attentional, linguistic, and visual features during object naming

    PubMed Central

    Clarke, Alasdair D. F.; Coco, Moreno I.; Keller, Frank

    2013-01-01

    Object detection and identification are fundamental to human vision, and there is mounting evidence that objects guide the allocation of visual attention. However, the role of objects in tasks involving multiple modalities is less clear. To address this question, we investigate object naming, a task in which participants have to verbally identify objects they see in photorealistic scenes. We report an eye-tracking study that investigates which features (attentional, visual, and linguistic) influence object naming. We find that the amount of visual attention directed toward an object, its position and saliency, along with linguistic factors such as word frequency, animacy, and semantic proximity, significantly influence whether the object will be named or not. We then ask how features from different modalities are combined during naming, and find significant interactions between saliency and position, saliency and linguistic features, and attention and position. We conclude that when the cognitive system performs tasks such as object naming, it uses input from one modality to constraint or enhance the processing of other modalities, rather than processing each input modality independently. PMID:24379792

  20. Mind over chatter: plastic up-regulation of the fMRI salience network directly after EEG neurofeedback.

    PubMed

    Ros, Tomas; Théberge, Jean; Frewen, Paul A; Kluetsch, Rosemarie; Densmore, Maria; Calhoun, Vince D; Lanius, Ruth A

    2013-01-15

    Neurofeedback (NFB) involves a brain-computer interface that allows users to learn to voluntarily control their cortical oscillations, reflected in the electroencephalogram (EEG). Although NFB is being pioneered as a noninvasive tool for treating brain disorders, there is insufficient evidence on the mechanism of its impact on brain function. Furthermore, the dominant rhythm of the human brain is the alpha oscillation (8-12 Hz), yet its behavioral significance remains multifaceted and largely correlative. In this study with 34 healthy participants, we examined whether during the performance of an attentional task, the functional connectivity of distinct fMRI networks would be plastically altered after a 30-min session of voluntary reduction of alpha rhythm (n=17) versus a sham-feedback condition (n=17). We reveal that compared to sham-feedback, NFB induced an increase of connectivity within regions of the salience network involved in intrinsic alertness (dorsal anterior cingulate), which was detectable 30 min after termination of training. The increase in salience network (default-mode network) connectivity was negatively (positively) correlated with changes in 'on task' mind-wandering as well as resting state alpha rhythm. Crucially, we observed a causal dependence between alpha rhythm synchronization during NFB and its subsequent change at resting state, not exhibited by the SHAM group. Our findings provide neurobehavioral evidence for the brain's exquisite functional plasticity, and for a temporally direct impact of NFB on a key cognitive control network, suggesting a promising basis for its use to treat cognitive disorders under physiological conditions. PMID:23022326

  1. The salience network dynamics in perceptual decision-making.

    PubMed

    Chand, Ganesh B; Dhamala, Mukesh

    2016-07-01

    Recent neuroimaging studies have demonstrated that the network consisting of the right anterior insula (rAI), left anterior insula (lAI) and dorsal anterior cingulate cortex (dACC) is activated in sensory stimulus-guided goal-directed behaviors. This network is often known as the salience network (SN). When and how a sensory signal enters and organizes within SN before reaching the central executive network including the prefrontal cortices is still a mystery. Previous electrophysiological studies focused on individual nodes of SN, either on dACC or rAI, have reports of conflicting findings of the earliest cortical activity within the network. Functional magnetic resonance imaging (fMRI) studies are not able to answer these questions in the time-scales of human sensory perception and decision-making. Here, using clear and noisy face-house image categorization tasks and human scalp electroencephalography (EEG) recordings combined with source reconstruction techniques, we study when and how oscillatory activity organizes SN during a perceptual decision. We uncovered that the beta-band (13-30Hz) oscillations bound SN, became most active around 100ms after the stimulus onset and the rAI acted as a main outflow hub within SN for easier decision making task. The SN activities (Granger causality measures) were negatively correlated with the decision response time (decision difficulty). These findings suggest that the SN activity precedes the executive control in mediating sensory and cognitive processing to arrive at visual perceptual decisions. PMID:27079535

  2. Altered salience network connectivity predicts macronutrient intake after sleep deprivation

    PubMed Central

    Fang, Zhuo; Spaeth, Andrea M.; Ma, Ning; Zhu, Senhua; Hu, Siyuan; Goel, Namni; Detre, John A.; Dinges, David F.; Rao, Hengyi

    2015-01-01

    Although insufficient sleep is a well-recognized risk factor for overeating and weight gain, the neural mechanisms underlying increased caloric (particularly fat) intake after sleep deprivation remain unclear. Here we used resting-state functional magnetic resonance imaging and examined brain connectivity changes associated with macronutrient intake after one night of total sleep deprivation (TSD). Compared to the day following baseline sleep, healthy adults consumed a greater percentage of calories from fat and a lower percentage of calories from carbohydrates during the day following TSD. Subjects also exhibited increased brain connectivity in the salience network from the dorsal anterior cingulate cortex (dACC) to bilateral putamen and bilateral anterior insula (aINS) after TSD. Moreover, dACC-putamen and dACC-aINS connectivity correlated with increased fat and decreased carbohydrate intake during the day following TSD, but not during the day following baseline sleep. These findings provide a potential neural mechanism by which sleep loss leads to increased fat intake. PMID:25645575

  3. Giving Good Directions: Order of Mention Reflects Visual Salience

    PubMed Central

    Clarke, Alasdair D. F.; Elsner, Micha; Rohde, Hannah

    2015-01-01

    In complex stimuli, there are many different possible ways to refer to a specified target. Previous studies have shown that when people are faced with such a task, the content of their referring expression reflects visual properties such as size, salience, and clutter. Here, we extend these findings and present evidence that (i) the influence of visual perception on sentence construction goes beyond content selection and in part determines the order in which different objects are mentioned and (ii) order of mention influences comprehension. Study 1 (a corpus study of reference productions) shows that when a speaker uses a relational description to mention a salient object, that object is treated as being in the common ground and is more likely to be mentioned first. Study 2 (a visual search study) asks participants to listen to referring expressions and find the specified target; in keeping with the above result, we find that search for easy-to-find targets is faster when the target is mentioned first, while search for harder-to-find targets is facilitated by mentioning the target later, after a landmark in a relational description. Our findings show that seemingly low-level and disparate mental “modules” like perception and sentence planning interact at a high level and in task-dependent ways. PMID:26696914

  4. Relative saliency of pitch versus phonetic cues in infancy

    NASA Astrophysics Data System (ADS)

    Cardillo, Gina; Kuhl, Patricia; Sundara, Megha

    2005-09-01

    Infants in their first year are highly sensitive to different acoustic components of speech, including phonetic detail and pitch information. The present investigation examined whether relative sensitivity to these two dimensions changes during this period, as the infant acquires language-specific phonetic categories. If pitch and phonetic discrimination are hierarchical, then the relative salience of pitch and phonetic change may become reversed between 8 and 12 months of age. Thirty-two- and 47-week-old infants were tested using an auditory preference paradigm in which they first heard a recording of a person singing a 4-note song (i.e., ``go-bi-la-tu'') and were then presented with both the familiar and an unfamiliar, modified version of that song. Modifications were either a novel pitch order (keeping syllables constant) or a novel syllable order (keeping melody constant). Compared to the younger group, older infants were predicted to show greater relative sensitivity to syllable order than pitch order, in accordance with an increased tendency to attend to linguistically relevant information (phonetic patterns) as opposed to cues that are initially more salient (pitch patterns). Preliminary data show trends toward the predicted interaction, with preference patterns commensurate with previously reported data. [Work supported by the McDonnell Foundation and NIH.

  5. Reward uncertainty enhances incentive salience attribution as sign-tracking

    PubMed Central

    Anselme, Patrick; Robinson, Mike J. F.; Berridge, Kent C.

    2014-01-01

    Conditioned stimuli (CSs) come to act as motivational magnets following repeated association with unconditioned stimuli (UCSs) such as sucrose rewards. By traditional views, the more reliably predictive a Pavlovian CS-UCS association, the more the CS becomes attractive. However, in some cases, less predictability might equal more motivation. Here we examined the effect of introducing uncertainty in CS-UCS association on CS strength as an attractive motivation magnet. In the present study, Experiment 1 assessed the effects of Pavlovian predictability versus uncertainty about reward probability and/or reward magnitude on the acquisition and expression of sign-tracking (ST) and goal-tracking (GT) responses in an autoshaping procedure. Results suggested that uncertainty produced strongest incentive salience expressed as sign-tracking. Experiment 2 examined whether a within-individual temporal shift from certainty to uncertainty conditions could produce a stronger CS motivational magnet when uncertainty began, and found that sign-tracking still increased after the shift. Overall, our results support earlier reports that ST responses become more pronounced in the presence of uncertainty regarding CS-UCS associations, especially when uncertainty combines both probability and magnitude. These results suggest that Pavlovian uncertainty, although diluting predictability, is still able to enhance the incentive motivational power of particular CSs. PMID:23078951

  6. Inhibition of eye blinking reveals subjective perceptions of stimulus salience.

    PubMed

    Shultz, Sarah; Klin, Ami; Jones, Warren

    2011-12-27

    Spontaneous eye blinking serves a critical physiological function, but it also interrupts incoming visual information. This tradeoff suggests that the inhibition of eye blinks might constitute an adaptive reaction to minimize the loss of visual information, particularly information that a viewer perceives to be important. To test this hypothesis, we examined whether the timing of blink inhibition, during natural viewing, is modulated between as well as within tasks, and also whether the timing of blink inhibition varies as a function of viewer engagement and stimulus event type. While viewing video scenes, we measured the timing of blinks and blink inhibition, as well as visual scanning, in a group of typical two-year-olds, and in a group of two-year-olds known for attenuated reactivity to affective stimuli: toddlers with Autism Spectrum Disorders (ASD). Although both groups dynamically adjusted the timing of their blink inhibition at levels greater than expected by chance, they inhibited their blinking and shifted visual fixation differentially with respect to salient onscreen events. Moreover, typical toddlers inhibited their blinking earlier than toddlers with ASD, indicating active anticipation of the unfolding of those events. These findings indicate that measures of blink inhibition can serve as temporally precise markers of perceived stimulus salience and are useful quantifiers of atypical processing of social affective signals in toddlers with ASD. PMID:22160686

  7. The effects of mortality salience on escalation of commitment.

    PubMed

    Yen, Chih-Long; Lin, Chun-Yu

    2012-01-01

    Based on propositions derived from terror management theory (TMT), the current study proposes that people who are reminded of their mortality exhibit a higher degree of self-justification behavior to maintain their self-esteem. For this reason, they could be expected to stick with their previous decisions and invest an increasing amount of resources in those decisions, despite the fact that negative feedback has clearly indicated that they might be on a course toward failure (i.e., "escalation of commitment"). Our experiment showed that people who were reminded of their mortality were more likely to escalate their level of commitment by maintaining their current course of action. Two imaginary scenarios were tested. One of the scenarios involved deciding whether to send additional troops into the battlefield when previous attempts had failed; the other involved deciding whether to continue developing an anti-radar fighter plane when the enemy had already developed a device to detect it. The results supported our hypothesis that mortality salience increases the tendency to escalate one's level of commitment. PMID:22046990

  8. Language-experience plasticity in neural representation of changes in pitch salience.

    PubMed

    Krishnan, Ananthanarayan; Gandour, Jackson T; Suresh, Chandan H

    2016-04-15

    Neural representation of pitch-relevant information at the brainstem and cortical levels of processing is influenced by language experience. A well-known attribute of pitch is its salience. Brainstem frequency following responses and cortical pitch specific responses, recorded concurrently, were elicited by a pitch salience continuum spanning weak to strong pitch of a dynamic, iterated rippled noise pitch contour-homolog of a Mandarin tone. Our aims were to assess how language experience (Chinese, English) affects i) enhancement of neural activity associated with pitch salience at brainstem and cortical levels, ii) the presence of asymmetry in cortical pitch representation, and iii) patterns of relative changes in magnitude along the pitch salience continuum. Peak latency (Fz: Na, Pb, and Nb) was shorter in the Chinese than the English group across the continuum. Peak-to-peak amplitude (Fz: Na-Pb, Pb-Nb) of the Chinese group grew larger with increasing pitch salience, but an experience-dependent advantage was limited to the Na-Pb component. At temporal sites (T7/T8), the larger amplitude of the Chinese group across the continuum was both limited to the Na-Pb component and the right temporal site. At the brainstem level, F0 magnitude gets larger as you increase pitch salience, and it too reveals Chinese superiority. A direct comparison of cortical and brainstem responses for the Chinese group reveals different patterns of relative changes in magnitude along the pitch salience continuum. Such differences may point to a transformation in pitch processing at the cortical level presumably mediated by local sensory and/or extrasensory influence overlaid on the brainstem output. PMID:26903418

  9. Preference for Well-Balanced Saliency in Details Cropped from Photographs

    PubMed Central

    Abeln, Jonas; Fresz, Leonie; Amirshahi, Seyed Ali; McManus, I. Chris; Koch, Michael; Kreysa, Helene; Redies, Christoph

    2016-01-01

    Photographic cropping is the act of selecting part of a photograph to enhance its aesthetic appearance or visual impact. It is common practice with both professional (expert) and amateur (non-expert) photographers. In a psychometric study, McManus et al. (2011b) showed that participants cropped photographs confidently and reliably. Experts tended to select details from a wider range of positions than non-experts, but other croppers did not generally prefer details that were selected by experts. It remained unclear, however, on what grounds participants selected particular details from a photograph while avoiding other details. One of the factors contributing to cropping decision may be visual saliency. Indeed, various saliency-based computer algorithms are available for the automatic cropping of photographs. However, careful experimental studies on the relation between saliency and cropping are lacking to date. In the present study, we re-analyzed the data from the studies by McManus et al. (2011a,b), focusing on statistical image properties. We calculated saliency-based measures for details selected and details avoided during cropping. As expected, we found that selected details contain regions of higher saliency than avoided details on average. Moreover, the saliency center-of-mass was closer to the geometrical center in selected details than in avoided details. Results were confirmed in an eye tracking study with the same dataset of images. Interestingly, the observed regularities in cropping behavior were less pronounced for experts than for non-experts. In summary, our results suggest that, during cropping, participants tend to select salient regions and place them in an image composition that is well-balanced with respect to the distribution of saliency. Our study contributes to the knowledge of perceptual bottom-up features that are germane to aesthetic decisions in photography and their variability in non-experts and experts. PMID:26793086

  10. Striatal Activity is Associated with Deficits of Cognitive Control and Aberrant Salience for Patients with Schizophrenia

    PubMed Central

    Ceaser, Alan E.; Barch, Deanna M.

    2016-01-01

    A recent meta-analysis has shown that a large dopamine abnormality exists in the striatum when comparing patients with schizophrenia and controls, and this abnormality is thought to contribute to aberrant salience assignment (or a misattribution of relevance to irrelevant stimuli). This abnormality may also disrupt striatal contributions to cognitive control processing. We examined the relationship between striatal involvement in cognition and aberrant salience symptoms using a task of cognitive control that involves updating, interference control, and simple maintenance. The current study included a sample of 22 patients with schizophrenia and 20 healthy controls and used a slow event-related fMRI design. We predicted that (1) aberrant salience symptoms would be greater for patient's, (2) patients would demonstrate increased errors during interference control trials, given that patients may be inappropriately assigning salience to distracters, and (3) striatal activity during those errors would be correlated with aberrant salience symptoms. We found a trend toward a significant difference between patients and controls on aberrant salience symptoms, and a significant difference between groups on select task conditions. During interference control trials, patients were more likely to inappropriately encode distracters. For patients, both prefrontal and striatal activity was significantly greater when patients inappropriately identified the distracter as correct compared to activity during distracter rejection. During updating, patient prefrontal and striatal activity was significantly lower for incorrect than correct updating trials. Finally, as predicted, for patients the increase of activity during incorrect distracter trials was positively correlated with aberrant salience symptoms, but only for the striatal region. These relationships may have implications for treatments that improve cognitive function and reduce symptom expression. PMID:26869912

  11. Short Cue Presentations Encourage Advance Task Preparation: A Recipe to Diminish the Residual Switch Cost

    ERIC Educational Resources Information Center

    Verbruggen, Frederick; Liefooghe, Baptist; Vandierendonck, Andre; Demanet, Jelle

    2007-01-01

    In the task-switching literature, it has frequently been demonstrated that although advance task preparation reduces the switch cost, it never really eliminates the switch cost. This remaining residual switch cost received much attention, and it has been argued that advance preparation is restricted in nature. In the present study, the role of…

  12. Distinct Global Brain Dynamics and Spatiotemporal Organization of the Salience Network.

    PubMed

    Chen, Tianwen; Cai, Weidong; Ryali, Srikanth; Supekar, Kaustubh; Menon, Vinod

    2016-06-01

    One of the most fundamental features of the human brain is its ability to detect and attend to salient goal-relevant events in a flexible manner. The salience network (SN), anchored in the anterior insula and the dorsal anterior cingulate cortex, plays a crucial role in this process through rapid detection of goal-relevant events and facilitation of access to appropriate cognitive resources. Here, we leverage the subsecond resolution of large multisession fMRI datasets from the Human Connectome Project and apply novel graph-theoretical techniques to investigate the dynamic spatiotemporal organization of the SN. We show that the large-scale brain dynamics of the SN are characterized by several distinctive and robust properties. First, the SN demonstrated the highest levels of flexibility in time-varying connectivity with other brain networks, including the frontoparietal network (FPN), the cingulate-opercular network (CON), and the ventral and dorsal attention networks (VAN and DAN). Second, dynamic functional interactions of the SN were among the most spatially varied in the brain. Third, SN nodes maintained a consistently high level of network centrality over time, indicating that this network is a hub for facilitating flexible cross-network interactions. Fourth, time-varying connectivity profiles of the SN were distinct from all other prefrontal control systems. Fifth, temporal flexibility of the SN uniquely predicted individual differences in cognitive flexibility. Importantly, each of these results was also observed in a second retest dataset, demonstrating the robustness of our findings. Our study provides fundamental new insights into the distinct dynamic functional architecture of the SN and demonstrates how this network is uniquely positioned to facilitate interactions with multiple functional systems and thereby support a wide range of cognitive processes in the human brain. PMID:27270215

  13. Determinants of Laser-Evoked EEG Responses: Pain Perception or Stimulus Saliency?

    PubMed Central

    Iannetti, G. D.; Hughes, N. P.; Lee, M. C.; Mouraux, A.

    2008-01-01

    Although laser-evoked electroencephalographic (EEG) responses are increasingly used to investigate nociceptive pathways, their functional significance remains unclear. The reproducible observation of a robust correlation between the intensity of pain perception and the magnitude of the laser-evoked N1, N2, and P2 responses has led some investigators to consider these responses a direct correlate of the neural activity responsible for pain intensity coding in the human cortex. Here, we provide compelling evidence to the contrary. By delivering trains of three identical laser pulses at four different energies, we explored the modulation exerted by the temporal expectancy of the stimulus on the relationship between intensity of pain perception and magnitude of the following laser-evoked brain responses: the phase-locked N1, N2, and P2 waves, and the non-phase-locked laser-induced synchronization (ERS) and desynchronization (ERD). We showed that increasing the temporal expectancy of the stimulus through stimulus repetition at a constant interstimulus interval 1) significantly reduces the magnitudes of the laser-evoked N1, N2, P2, and ERS; and 2) disrupts the relationship between the intensity of pain perception and the magnitude of these responses. Taken together, our results indicate that laser-evoked EEG responses are not determined by the perception of pain per se, but are mainly determined by the saliency of the eliciting nociceptive stimulus (i.e., its ability to capture attention). Therefore laser-evoked EEG responses represent an indirect readout of the function of the nociceptive system. PMID:18525021

  14. Distinct Global Brain Dynamics and Spatiotemporal Organization of the Salience Network

    PubMed Central

    Chen, Tianwen; Cai, Weidong; Ryali, Srikanth; Supekar, Kaustubh; Menon, Vinod

    2016-01-01

    One of the most fundamental features of the human brain is its ability to detect and attend to salient goal-relevant events in a flexible manner. The salience network (SN), anchored in the anterior insula and the dorsal anterior cingulate cortex, plays a crucial role in this process through rapid detection of goal-relevant events and facilitation of access to appropriate cognitive resources. Here, we leverage the subsecond resolution of large multisession fMRI datasets from the Human Connectome Project and apply novel graph-theoretical techniques to investigate the dynamic spatiotemporal organization of the SN. We show that the large-scale brain dynamics of the SN are characterized by several distinctive and robust properties. First, the SN demonstrated the highest levels of flexibility in time-varying connectivity with other brain networks, including the frontoparietal network (FPN), the cingulate–opercular network (CON), and the ventral and dorsal attention networks (VAN and DAN). Second, dynamic functional interactions of the SN were among the most spatially varied in the brain. Third, SN nodes maintained a consistently high level of network centrality over time, indicating that this network is a hub for facilitating flexible cross-network interactions. Fourth, time-varying connectivity profiles of the SN were distinct from all other prefrontal control systems. Fifth, temporal flexibility of the SN uniquely predicted individual differences in cognitive flexibility. Importantly, each of these results was also observed in a second retest dataset, demonstrating the robustness of our findings. Our study provides fundamental new insights into the distinct dynamic functional architecture of the SN and demonstrates how this network is uniquely positioned to facilitate interactions with multiple functional systems and thereby support a wide range of cognitive processes in the human brain. PMID:27270215

  15. Cognitive control and the salience network: an investigation of error processing and effective connectivity.

    PubMed

    Ham, Timothy; Leff, Alex; de Boissezon, Xavier; Joffe, Anna; Sharp, David J

    2013-04-17

    The Salience Network (SN) consists of the dorsal anterior cingulate cortex (dACC) and bilateral insulae. The network responds to behaviorally salient events, and an important question is how its nodes interact. One theory is that the dACC provides the earliest cortical signal of behaviorally salient events, such as errors. Alternatively, the anterior right insula (aRI) has been proposed to provide an early cognitive control signal. As these regions frequently coactivate, it has been difficult to disentangle their roles using conventional methods. Here we use dynamic causal modeling and a Bayesian model evidence technique to investigate the causal relationships between nodes in the SN after errors. Thirty-five human subjects performed the Simon task. The task has two conditions (congruent and incongruent) producing two distinct error types. Neural activity associated with errors was investigated using fMRI. Subjects made a total of 1319 congruent and 1617 incongruent errors. Errors resulted in robust activation of the SN. Dynamic causal modeling analyses demonstrated that input into the SN was most likely via the aRI for both error types and that the aRI was the only region intrinsically connected to both other nodes. Only incongruent errors produced behavioral adaptation, and the strength of the connection between the dACC and the left insulae correlated with the extent of this behavioral change. We conclude that the aRI, not the dACC, drives the SN after errors on an attentionally demanding task, and that a change in the effective connectivity of the dACC is associated with behavioral adaptation after errors. PMID:23595766

  16. Salience of Guilty Knowledge Test items affects accuracy in realistic mock crimes.

    PubMed

    Jokinen, Anne; Santtila, Pekka; Ravaja, Niklas; Puttonen, Sampsa

    2006-10-01

    Guilty Knowledge Test measuring electrodermal reactions was carried out in order to investigate the quality of different questions and the validity of the test in a situation that resembled a true crime. Fifty participants were randomly assigned to commit one of two realistic mock crimes, and were later tested with GKTs concerning both the crime they had enacted and the one they had no knowledge of. Different scoring systems (SCRs and peak amplitudes as well as raw and standardised scores) were employed and compared when analyzing the results. Although there were some false positives, the test was able to differentiate between the groups of guilty and innocent participants. With the best scoring systems, the test was able to classify up to 84% of the innocent and up to 76% of the guilty correctly according to a logistic regression analysis. ROC areas reflecting these same results reached values above .80. Questions on matters that demanded the participants' attention and were easier to remember had better discriminative power. With nearly all scoring methods, there was a significant interaction between the salience of the relevant items and the guilt of the participants. Participants reacted more strongly to salient relevant items when they were guilty, while no different reactions were observed for the non-salient items between guilty and innocent participants. It is suggested that, although the Guilty Knowledge Test appears to be a valid measure of guilty knowledge even in crimes that are close to real crimes, the principles on which guilty knowledge test questions are constructed should be more clearly specified. PMID:16766070

  17. Nanoelectromechanical contact switches

    NASA Astrophysics Data System (ADS)

    Loh, Owen Y.; Espinosa, Horacio D.

    2012-05-01

    Nanoelectromechanical (NEM) switches are similar to conventional semiconductor switches in that they can be used as relays, transistors, logic devices and sensors. However, the operating principles of NEM switches and semiconductor switches are fundamentally different. These differences give NEM switches an advantage over semiconductor switches in some applications -- for example, NEM switches perform much better in extreme environments -- but semiconductor switches benefit from a much superior manufacturing infrastructure. Here we review the potential of NEM-switch technologies to complement or selectively replace conventional complementary metal-oxide semiconductor technology, and identify the challenges involved in the large-scale manufacture of a representative set of NEM-based devices.

  18. Attentional Flexibility During Approach and Avoidance Motivational States: The Role of Context in Shifts of Attentional Breadth

    PubMed Central

    Calcott, Rebecca D.; Berkman, Elliot T.

    2014-01-01

    In the present studies, we aimed to understand how approach and avoidance states affect attentional flexibility by examining attentional shifts on a trial-by-trial basis. We also examined how a novel construct in this area, task context, might interact with motivation to influence attentional flexibility. Participants completed a modified composite letter task in which the ratio of global to local targets was varied by block, making different levels of attentional focus beneficial to performance on different blocks. Study 1 demonstrated that, in the absence of a motivation manipulation, switch costs were lowest on blocks with an even ratio of global and local trials and were higher on blocks with an uneven ratio. Other participants completed the task while viewing pictures (Studies 2 and 3) and assuming arm positions (Studies 2 and 4) to induce approach, avoidance, and neutral motivational states. Avoidance motivation reduced switch costs in evenly proportioned contexts, whereas approach motivation reduced switch costs in mostly global contexts. Additionally, approach motivation imparted a similar switch cost magnitude across different contexts, whereas avoidance and neutral states led to variable switch costs depending on the context. Subsequent analyses revealed that these effects were driven largely by faster switching to local targets on mostly global blocks in the approach condition. These findings suggest that avoidance facilitates attentional shifts when switches are frequent, whereas approach facilitates responding to rare or unexpected local stimuli. The main implication of these results is that motivation has different effects on attentional shifts depending on the context. PMID:24294866

  19. Modeling selective attention using a neuromorphic analog VLSI device.

    PubMed

    Indiveri, G

    2000-12-01

    Attentional mechanisms are required to overcome the problem of flooding a limited processing capacity system with information. They are present in biological sensory systems and can be a useful engineering tool for artificial visual systems. In this article we present a hardware model of a selective attention mechanism implemented on a very large-scale integration (VLSI) chip, using analog neuromorphic circuits. The chip exploits a spike-based representation to receive, process, and transmit signals. It can be used as a transceiver module for building multichip neuromorphic vision systems. We describe the circuits that carry out the main processing stages of the selective attention mechanism and provide experimental data for each circuit. We demonstrate the expected behavior of the model at the system level by stimulating the chip with both artificially generated control signals and signals obtained from a saliency map, computed from an image containing several salient features. PMID:11112258

  20. Auditory pre-experience modulates classification of affect intensity: evidence for the evaluation of call salience by a non-human mammal, the bat Megaderma lyra

    PubMed Central

    2013-01-01

    Introduction Immediate responses towards emotional utterances in humans are determined by the acoustic structure and perceived relevance, i.e. salience, of the stimuli, and are controlled via a central feedback taking into account acoustic pre-experience. The present study explores whether the evaluation of stimulus salience in the acoustic communication of emotions is specifically human or has precursors in mammals. We created different pre-experiences by habituating bats (Megaderma lyra) to stimuli based on aggression, and response, calls from high or low intensity level agonistic interactions, respectively. Then we presented a test stimulus of opposite affect intensity of the same call type. We compared the modulation of response behaviour by affect intensity between the reciprocal experiments. Results For aggression call stimuli, the bats responded to the dishabituation stimuli independent of affect intensity, emphasising the attention-grabbing function of this call type. For response call stimuli, the bats responded to a high affect intensity test stimulus after experiencing stimuli of low affect intensity, but transferred habituation to a low affect intensity test stimulus after experiencing stimuli of high affect intensity. This transfer of habituation was not due to over-habituation as the bats responded to a frequency-shifted control stimulus. A direct comparison confirmed the asymmetric response behaviour in the reciprocal experiments. Conclusions Thus, the present study provides not only evidence for a discrimination of affect intensity, but also for an evaluation of stimulus salience, suggesting that basic assessment mechanisms involved in the perception of emotion are an ancestral trait in mammals. PMID:24341839

  1. The Spatial Attention Network Interacts with Limbic and Monoaminergic Systems to Modulate Motivation-Induced Attention Shifts

    PubMed Central

    Gitelman, Darren R.; Small, Dana M.; Mesulam, M. Marsel

    2008-01-01

    How does the human brain integrate information from multiple domains to guide spatial attention according to motivational needs? To address this question, we measured hemodynamic responses to central cues predicting locations of peripheral attentional targets (food or tool images) in a novel covert spatial attention paradigm. The motivational relevance of food-related attentional targets was experimentally manipulated via hunger and satiety. Amygdala, posterior cingulate, locus coeruleus, and substantia nigra showed selective sensitivity to food-related cues when hungry but not when satiated, an effect that did not generalize to tools. Posterior parietal cortex (PPC), including intraparietal sulcus, posterior cingulate, and the orbitofrontal cortex displayed correlations with the speed of attentional shifts that were sensitive not just to motivational state but also to the motivational value of the target. Stronger functional coupling between PPC and posterior cingulate occurred during attentional biasing toward motivationally relevant food targets. These results reveal conjoint limbic and monoaminergic encoding of motivational salience in spatial attention. They emphasize the interactive role of posterior parietal and cingulate cortices in integrating motivational information with spatial attention, a process that is critical for selective allocation of attentional resources in an environment where target position and relevance can change rapidly. PMID:18308706

  2. Abnormal salience signaling in schizophrenia: The role of integrative beta oscillations

    PubMed Central

    Liddle, Elizabeth B.; Price, Darren; Palaniyappan, Lena; Brookes, Matthew J.; Robson, Siân E.; Hall, Emma L.; Morris, Peter G.

    2016-01-01

    Abstract Aberrant salience attribution and cerebral dysconnectivity both have strong evidential support as core dysfunctions in schizophrenia. Aberrant salience arising from an excess of dopamine activity has been implicated in delusions and hallucinations, exaggerating the significance of everyday occurrences and thus leading to perceptual distortions and delusional causal inferences. Meanwhile, abnormalities in key nodes of a salience brain network have been implicated in other characteristic symptoms, including the disorganization and impoverishment of mental activity. A substantial body of literature reports disruption to brain network connectivity in schizophrenia. Electrical oscillations likely play a key role in the coordination of brain activity at spatially remote sites, and evidence implicates beta band oscillations in long‐range integrative processes. We used magnetoencephalography and a task designed to disambiguate responses to relevant from irrelevant stimuli to investigate beta oscillations in nodes of a network implicated in salience detection and previously shown to be structurally and functionally abnormal in schizophrenia. Healthy participants, as expected, produced an enhanced beta synchronization to behaviorally relevant, as compared to irrelevant, stimuli, while patients with schizophrenia showed the reverse pattern: a greater beta synchronization in response to irrelevant than to relevant stimuli. These findings not only support both the aberrant salience and disconnectivity hypotheses, but indicate a common mechanism that allows us to integrate them into a single framework for understanding schizophrenia in terms of disrupted recruitment of contextually appropriate brain networks. Hum Brain Mapp 37:1361‐1374, 2016. © 2016 Wiley Periodicals, Inc. PMID:26853904

  3. Image Processing Strategies Based on a Visual Saliency Model for Object Recognition Under Simulated Prosthetic Vision.

    PubMed

    Wang, Jing; Li, Heng; Fu, Weizhen; Chen, Yao; Li, Liming; Lyu, Qing; Han, Tingting; Chai, Xinyu

    2016-01-01

    Retinal prostheses have the potential to restore partial vision. Object recognition in scenes of daily life is one of the essential tasks for implant wearers. Still limited by the low-resolution visual percepts provided by retinal prostheses, it is important to investigate and apply image processing methods to convey more useful visual information to the wearers. We proposed two image processing strategies based on Itti's visual saliency map, region of interest (ROI) extraction, and image segmentation. Itti's saliency model generated a saliency map from the original image, in which salient regions were grouped into ROI by the fuzzy c-means clustering. Then Grabcut generated a proto-object from the ROI labeled image which was recombined with background and enhanced in two ways--8-4 separated pixelization (8-4 SP) and background edge extraction (BEE). Results showed that both 8-4 SP and BEE had significantly higher recognition accuracy in comparison with direct pixelization (DP). Each saliency-based image processing strategy was subject to the performance of image segmentation. Under good and perfect segmentation conditions, BEE and 8-4 SP obtained noticeably higher recognition accuracy than DP, and under bad segmentation condition, only BEE boosted the performance. The application of saliency-based image processing strategies was verified to be beneficial to object recognition in daily scenes under simulated prosthetic vision. They are hoped to help the development of the image processing module for future retinal prostheses, and thus provide more benefit for the patients. PMID:25981202

  4. Women's hormone levels modulate the motivational salience of facial attractiveness and sexual dimorphism.

    PubMed

    Wang, Hongyi; Hahn, Amanda C; Fisher, Claire I; DeBruine, Lisa M; Jones, Benedict C

    2014-12-01

    The physical attractiveness of faces is positively correlated with both behavioral and neural measures of their motivational salience. Although previous work suggests that hormone levels modulate women's perceptions of others' facial attractiveness, studies have not yet investigated whether hormone levels also modulate the motivational salience of facial characteristics. To address this issue, we investigated the relationships between within-subject changes in women's salivary hormone levels (estradiol, progesterone, testosterone, and estradiol-to-progesterone ratio) and within-subject changes in the motivational salience of attractiveness and sexual dimorphism in male and female faces. The motivational salience of physically attractive faces in general and feminine female faces, but not masculine male faces, was greater in test sessions where women had high testosterone levels. Additionally, the reward value of sexually dimorphic faces in general and attractive female faces, but not attractive male faces, was greater in test sessions where women had high estradiol-to-progesterone ratios. These results provide the first evidence that the motivational salience of facial attractiveness and sexual dimorphism is modulated by within-woman changes in hormone levels. PMID:25244638

  5. The electrophysiological correlate of saliency: evidence from a figure-detection task.

    PubMed

    Straube, Sirko; Fahle, Manfred

    2010-01-11

    Although figure-ground segregation in a natural environment usually relies on multiple cues, we experience a coherent figure without usually noticing the individual single cues. It is still unclear how various cues interact to achieve this unified percept and whether this interaction depends on task demands. Studies investigating the effect of cue combination on the human EEG are still lacking. In the present study, we combined psychophysics, ERP and time-frequency analysis to investigate the interaction of orientation and spatial frequency as visual cues in a figure detection task. The figure was embedded in a matrix of Gabor elements, and we systematically varied figure saliency by changing the underlying cue configuration. We found a strong correlation between the posterior P2 amplitude and the perceived saliency of the figure: the P2 amplitude decreased with increasing saliency. Analogously, the power of the theta-band decreased for more salient figures. At longer latencies, the posterior P3 component was modulated in amplitude and latency, possibly reflecting increased decision confidence at higher saliencies. In conclusion, when the cue composition (e.g. one or two cues) or cue strength is changed in a figure detection task, first differences in the electrophysiological response reflect the perceived saliency and not directly the underlying cue configuration. PMID:19854163

  6. The habenula governs the attribution of incentive salience to reward predictive cues

    PubMed Central

    Danna, Carey L.; Shepard, Paul D.; Elmer, Greg I.

    2013-01-01

    The attribution of incentive salience to reward associated cues is critical for motivation and the pursuit of rewards. Disruptions in the integrity of the neural systems controlling these processes can lead to avolition and anhedonia, symptoms that cross the diagnostic boundaries of many neuropsychiatric illnesses. Here, we consider whether the habenula (Hb), a region recently demonstrated to encode negatively valenced events, also modulates the attribution of incentive salience to a neutral cue predicting a food reward. The Pavlovian autoshaping paradigm was used in the rat as an investigative tool to dissociate Pavlovian learning processes imparting strictly predictive value from learning that attributes incentive motivational value. Electrolytic lesions of the fasciculus retroflexus (fr), the sole pathway through which descending Hb efferents are conveyed, significantly increased incentive salience as measured by conditioned approaches to a cue light predictive of reward. Conversely, generation of a fictive Hb signal via fr stimulation during CS+ presentation significantly decreased the incentive salience of the predictive cue. Neither manipulation altered the reward predictive value of the cue as measured by conditioned approach to the food. Our results provide new evidence supporting a significant role for the Hb in governing the attribution of incentive motivational salience to reward predictive cues and further imply that pathological changes in Hb activity could contribute to the aberrant pursuit of debilitating goals or avolition and depression-like symptoms. PMID:24368898

  7. Abnormal salience signaling in schizophrenia: The role of integrative beta oscillations.

    PubMed

    Liddle, Elizabeth B; Price, Darren; Palaniyappan, Lena; Brookes, Matthew J; Robson, Siân E; Hall, Emma L; Morris, Peter G; Liddle, Peter F

    2016-04-01

    Aberrant salience attribution and cerebral dysconnectivity both have strong evidential support as core dysfunctions in schizophrenia. Aberrant salience arising from an excess of dopamine activity has been implicated in delusions and hallucinations, exaggerating the significance of everyday occurrences and thus leading to perceptual distortions and delusional causal inferences. Meanwhile, abnormalities in key nodes of a salience brain network have been implicated in other characteristic symptoms, including the disorganization and impoverishment of mental activity. A substantial body of literature reports disruption to brain network connectivity in schizophrenia. Electrical oscillations likely play a key role in the coordination of brain activity at spatially remote sites, and evidence implicates beta band oscillations in long-range integrative processes. We used magnetoencephalography and a task designed to disambiguate responses to relevant from irrelevant stimuli to investigate beta oscillations in nodes of a network implicated in salience detection and previously shown to be structurally and functionally abnormal in schizophrenia. Healthy participants, as expected, produced an enhanced beta synchronization to behaviorally relevant, as compared to irrelevant, stimuli, while patients with schizophrenia showed the reverse pattern: a greater beta synchronization in response to irrelevant than to relevant stimuli. These findings not only support both the aberrant salience and disconnectivity hypotheses, but indicate a common mechanism that allows us to integrate them into a single framework for understanding schizophrenia in terms of disrupted recruitment of contextually appropriate brain networks. Hum Brain Mapp 37:1361-1374, 2016. © 2016 Wiley Periodicals, Inc. PMID:26853904

  8. Quantifying individual variation in the propensity to attribute incentive salience to reward cues.

    PubMed

    Meyer, Paul J; Lovic, Vedran; Saunders, Benjamin T; Yager, Lindsay M; Flagel, Shelly B; Morrow, Jonathan D; Robinson, Terry E

    2012-01-01

    If reward-associated cues acquire the properties of incentive stimuli they can come to powerfully control behavior, and potentially promote maladaptive behavior. Pavlovian incentive stimuli are defined as stimuli that have three fundamental properties: they are attractive, they are themselves desired, and they can spur instrumental actions. We have found, however, that there is considerable individual variation in the extent to which animals attribute Pavlovian incentive motivational properties ("incentive salience") to reward cues. The purpose of this paper was to develop criteria for identifying and classifying individuals based on their propensity to attribute incentive salience to reward cues. To do this, we conducted a meta-analysis of a large sample of rats (N = 1,878) subjected to a classic Pavlovian conditioning procedure. We then used the propensity of animals to approach a cue predictive of reward (one index of the extent to which the cue was attributed with incentive salience), to characterize two behavioral phenotypes in this population: animals that approached the cue ("sign-trackers") vs. others that approached the location of reward delivery ("goal-trackers"). This variation in Pavlovian approach behavior predicted other behavioral indices of the propensity to attribute incentive salience to reward cues. Thus, the procedures reported here should be useful for making comparisons across studies and for assessing individual variation in incentive salience attribution in small samples of the population, or even for classifying single animals. PMID:22761718

  9. Using Highlighting to Train Attentional Expertise.

    PubMed

    Roads, Brett; Mozer, Michael C; Busey, Thomas A

    2016-01-01

    Acquiring expertise in complex visual tasks is time consuming. To facilitate the efficient training of novices on where to look in these tasks, we propose an attentional highlighting paradigm. Highlighting involves dynamically modulating the saliency of a visual image to guide attention along the fixation path of a domain expert who had previously viewed the same image. In Experiment 1, we trained naive subjects via attentional highlighting on a fingerprint-matching task. Before and after training, we asked subjects to freely inspect images containing pairs of prints and determine whether the prints matched. Fixation sequences were automatically scored for the degree of expertise exhibited using a Bayesian discriminative model of novice and expert gaze behavior. Highlighted training causes gaze behavior to become more expert-like not only on the trained images but also on transfer images, indicating generalization of learning. In Experiment 2, to control for the possibility that the increase in expertise is due to mere exposure, we trained subjects via highlighting of fixation sequences from novices, not experts, and observed no transition toward expertise. In Experiment 3, to determine the specificity of the training effect, we trained subjects with expert fixation sequences from images other than the one being viewed, which preserves coarse-scale statistics of expert gaze but provides no information about fine-grain features. Observing at least a partial transition toward expertise, we obtain only weak evidence that the highlighting procedure facilitates the learning of critical local features. We discuss possible improvements to the highlighting procedure. PMID:26744839

  10. Using Highlighting to Train Attentional Expertise

    PubMed Central

    Roads, Brett; Mozer, Michael C.; Busey, Thomas A.

    2016-01-01

    Acquiring expertise in complex visual tasks is time consuming. To facilitate the efficient training of novices on where to look in these tasks, we propose an attentional highlighting paradigm. Highlighting involves dynamically modulating the saliency of a visual image to guide attention along the fixation path of a domain expert who had previously viewed the same image. In Experiment 1, we trained naive subjects via attentional highlighting on a fingerprint-matching task. Before and after training, we asked subjects to freely inspect images containing pairs of prints and determine whether the prints matched. Fixation sequences were automatically scored for the degree of expertise exhibited using a Bayesian discriminative model of novice and expert gaze behavior. Highlighted training causes gaze behavior to become more expert-like not only on the trained images but also on transfer images, indicating generalization of learning. In Experiment 2, to control for the possibility that the increase in expertise is due to mere exposure, we trained subjects via highlighting of fixation sequences from novices, not experts, and observed no transition toward expertise. In Experiment 3, to determine the specificity of the training effect, we trained subjects with expert fixation sequences from images other than the one being viewed, which preserves coarse-scale statistics of expert gaze but provides no information about fine-grain features. Observing at least a partial transition toward expertise, we obtain only weak evidence that the highlighting procedure facilitates the learning of critical local features. We discuss possible improvements to the highlighting procedure. PMID:26744839

  11. THYRATRON SWITCH

    DOEpatents

    Creveling, R.; Bourgeois, N.A. Jr.

    1959-04-21

    An arrangement for utilizing a thyratron as a noise free switch is described. It has been discovered that the voltage between plate and cathode of a thyratron will oscillate, producing voltage spikes, if the tube carries only a fraction of its maximum rated current. These voltage spikes can produce detrimental effects where the thyratron is used in critical timing circuits. To alleviate this problem the disclosed circuit provides a charged capacitor and a resistor in parallel with the tube and of such value that the maximum current will flow from the capacitor through the thyratron when it is triggered. During this time the signal current is conducted through the tube, before the thyratron voltage starts to oscillate, and the signal current output is free of noise spikes.

  12. Mortality salience, martyrdom, and military might: the great satan versus the axis of evil.

    PubMed

    Pyszczynski, Tom; Abdollahi, Abdolhossein; Solomon, Sheldon; Greenberg, Jeff; Cohen, Florette; Weise, David

    2006-04-01

    Study 1 investigated the effect of mortality salience on support for martyrdom attacks among Iranian college students. Participants were randomly assigned to answer questions about either their own death or an aversive topic unrelated to death and then evaluated materials from fellow students who either supported or opposed martyrdom attacks against the United States. Whereas control participants preferred the student who opposed martyrdom, participants reminded of death preferred the student who supported martyrdom and indicated they were more likely to consider such activities themselves. Study 2 investigated the effect of mortality salience on American college students' support for extreme military interventions by American forces that could kill thousands of civilians. Mortality salience increased support for such measures among politically conservative but not politically liberal students. The roles of existential fear, cultural worldviews, and construing one's nation as pursing a heroic battle against evil in advocacy of violence were discussed. PMID:16513804

  13. Robust single trial identification of conscious percepts triggered by sensory events of variable saliency.

    PubMed

    Teixeira, Marta; Pires, Gabriel; Raimundo, Miguel; Nascimento, Sérgio; Almeida, Vasco; Castelo-Branco, Miguel

    2014-01-01

    The neural correlates of visual awareness are elusive because of its fleeting nature. Here we have addressed this issue by using single trial statistical "brain reading" of neurophysiological event related (ERP) signatures of conscious perception of visual attributes with different levels of saliency. Behavioral reports were taken at every trial in 4 experiments addressing conscious access to color, luminance, and local phase offset cues. We found that single trial neurophysiological signatures of target presence can be observed around 300 ms at central parietal sites. Such signatures are significantly related with conscious perception, and their probability is related to sensory saliency levels. These findings identify a general neural correlate of conscious perception at the single trial level, since conscious perception can be decoded as such independently of stimulus salience and fluctuations of threshold levels. This approach can be generalized to successfully detect target presence in other individuals. PMID:24465957

  14. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map

    PubMed Central

    Tan, Yihua; Li, Qingyun; Li, Yansheng; Tian, Jinwen

    2015-01-01

    This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate. PMID:26378543

  15. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map.

    PubMed

    Tan, Yihua; Li, Qingyun; Li, Yansheng; Tian, Jinwen

    2015-01-01

    This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate. PMID:26378543

  16. Neural Dynamics of Emotional Salience Processing in Response to Voices during the Stages of Sleep

    PubMed Central

    Chen, Chenyi; Sung, Jia-Ying; Cheng, Yawei

    2016-01-01

    Sleep has been related to emotional functioning. However, the extent to which emotional salience is processed during sleep is unknown. To address this concern, we investigated night sleep in healthy adults regarding brain reactivity to the emotionally (happily, fearfully) spoken meaningless syllables dada, along with correspondingly synthesized nonvocal sounds. Electroencephalogram (EEG) signals were continuously acquired during an entire night of sleep while we applied a passive auditory oddball paradigm. During all stages of sleep, mismatch negativity (MMN) in response to emotional syllables, which is an index for emotional salience processing of voices, was detected. In contrast, MMN to acoustically matching nonvocal sounds was undetected during Sleep Stage 2 and 3 as well as rapid eye movement (REM) sleep. Post-MMN positivity (PMP) was identified with larger amplitudes during Stage 3, and at earlier latencies during REM sleep, relative to wakefulness. These findings clearly demonstrated the neural dynamics of emotional salience processing during the stages of sleep. PMID:27378870

  17. A New Method for Calibrating Perceptual Salience across Dimensions in Infants: The Case of Color vs. Luminance

    ERIC Educational Resources Information Center

    Kaldy, Zsuzsa; Blaser, Erik A.; Leslie, Alan M.

    2006-01-01

    We report a new method for calibrating differences in perceptual salience across feature dimensions, in infants. The problem of inter-dimensional salience arises in many areas of infant studies, but a general method for addressing the problem has not previously been described. Our method is based on a preferential looking paradigm, adapted to…

  18. Sociopolitical Development, Work Salience, and Vocational Expectations among Low Socioeconomic Status African American, Latin American, and Asian American Youth

    ERIC Educational Resources Information Center

    Diemer, Matthew A.; Wang, Qiu; Moore, Traymanesha; Gregory, Shannon R.; Hatcher, Keisha M.; Voight, Adam M.

    2010-01-01

    Structural barriers constrain marginalized youths' development of work salience and vocational expectations. Sociopolitical development (SPD), the consciousness of, and motivation to reduce, sociopolitical inequality, may facilitate the negotiation of structural constraints. A structural model of SPD's impact on work salience and vocational…

  19. The effect of dopamine agonists on adaptive and aberrant salience in Parkinson's disease.

    PubMed

    Nagy, Helga; Levy-Gigi, Einat; Somlai, Zsuzsanna; Takáts, Annamária; Bereczki, Dániel; Kéri, Szabolcs

    2012-03-01

    Clinical evidence suggests that after initiation of dopaminergic medications some patients with Parkinson's disease (PD) develop psychotic symptoms, such as hallucinations and delusions. Here, we tested the hypothesis that the neurocognitive basis of this phenomenon can be defined as the formation of arbitrary and illusory associations between conditioned stimuli and reward signals, called aberrant salience. Young, never-medicated PD patients and matched controls were assessed on a speeded reaction time task in which the probe stimulus was preceded by conditioned stimuli that could signal monetary reward by color or shape. The patients and controls were re-evaluated after 12 weeks during which the patients received a dopamine agonist (pramipexole or ropinirole). Results indicated that dopamine agonists increased both adaptive and aberrant salience in PD patients, that is, formation of real and illusory associations between conditioned stimuli and reward, respectively. This effect was present when associations were assessed by means of faster responding after conditioned stimuli signaling reward (implicit salience) and overt rating of stimulus-reward links (explicit salience). However, unusual feelings and experiences, which are subclinical manifestations of psychotic-like symptoms, were specifically related to irrelevant and illusory stimulus-reward associations (aberrant salience) in PD patients receiving dopamine agonists. The learning of relevant and real stimulus-reward associations (adaptive salience) was not related to unusual experiences. These results suggest that dopamine agonists may increase psychotic-like experiences in young patients with PD, possibly by facilitating dopaminergic transmission in the ventral striatum, which results in aberrant associations between conditioned stimuli and reward. PMID:22089321

  20. Toward isolating the role of dopamine in the acquisition of incentive salience attribution.

    PubMed

    Chow, Jonathan J; Nickell, Justin R; Darna, Mahesh; Beckmann, Joshua S

    2016-10-01

    Stimulus-reward learning has been heavily linked to the reward-prediction error learning hypothesis and dopaminergic function. However, some evidence suggests dopaminergic function may not strictly underlie reward-prediction error learning, but may be specific to incentive salience attribution. Utilizing a Pavlovian conditioned approach procedure consisting of two stimuli that were equally reward-predictive (both undergoing reward-prediction error learning) but functionally distinct in regard to incentive salience (levers that elicited sign-tracking and tones that elicited goal-tracking), we tested the differential role of D1 and D2 dopamine receptors and nucleus accumbens dopamine in the acquisition of sign- and goal-tracking behavior and their associated conditioned reinforcing value within individuals. Overall, the results revealed that both D1 and D2 inhibition disrupted performance of sign- and goal-tracking. However, D1 inhibition specifically prevented the acquisition of sign-tracking to a lever, instead promoting goal-tracking and decreasing its conditioned reinforcing value, while neither D1 nor D2 signaling was required for goal-tracking in response to a tone. Likewise, nucleus accumbens dopaminergic lesions disrupted acquisition of sign-tracking to a lever, while leaving goal-tracking in response to a tone unaffected. Collectively, these results are the first evidence of an intraindividual dissociation of dopaminergic function in incentive salience attribution from reward-prediction error learning, indicating that incentive salience, reward-prediction error, and their associated dopaminergic signaling exist within individuals and are stimulus-specific. Thus, individual differences in incentive salience attribution may be reflective of a differential balance in dopaminergic function that may bias toward the attribution of incentive salience, relative to reward-prediction error learning only. PMID:27371135

  1. The Effect of Dopamine Agonists on Adaptive and Aberrant Salience in Parkinson's Disease

    PubMed Central

    Nagy, Helga; Levy-Gigi, Einat; Somlai, Zsuzsanna; Takáts, Annamária; Bereczki, Dániel; Kéri, Szabolcs

    2012-01-01

    Clinical evidence suggests that after initiation of dopaminergic medications some patients with Parkinson's disease (PD) develop psychotic symptoms, such as hallucinations and delusions. Here, we tested the hypothesis that the neurocognitive basis of this phenomenon can be defined as the formation of arbitrary and illusory associations between conditioned stimuli and reward signals, called aberrant salience. Young, never-medicated PD patients and matched controls were assessed on a speeded reaction time task in which the probe stimulus was preceded by conditioned stimuli that could signal monetary reward by color or shape. The patients and controls were re-evaluated after 12 weeks during which the patients received a dopamine agonist (pramipexole or ropinirole). Results indicated that dopamine agonists increased both adaptive and aberrant salience in PD patients, that is, formation of real and illusory associations between conditioned stimuli and reward, respectively. This effect was present when associations were assessed by means of faster responding after conditioned stimuli signaling reward (implicit salience) and overt rating of stimulus–reward links (explicit salience). However, unusual feelings and experiences, which are subclinical manifestations of psychotic-like symptoms, were specifically related to irrelevant and illusory stimulus–reward associations (aberrant salience) in PD patients receiving dopamine agonists. The learning of relevant and real stimulus–reward associations (adaptive salience) was not related to unusual experiences. These results suggest that dopamine agonists may increase psychotic-like experiences in young patients with PD, possibly by facilitating dopaminergic transmission in the ventral striatum, which results in aberrant associations between conditioned stimuli and reward. PMID:22089321

  2. Alcohol administration increases cocaine craving but not cocaine cue attentional bias

    PubMed Central

    Marks, Katherine R.; Pike, Erika; Stoops, William W.; Rush, Craig R.

    2015-01-01

    Background Alcohol consumption is a known antecedent to cocaine relapse. Through associative conditioning, it is hypothesized that alcohol increases incentive motivation for cocaine and thus the salience of cocaine-related cues, which are important in maintaining drug-taking behavior. Cocaine-using individuals display a robust cocaine cue attentional bias as measured by fixation time during the visual probe task. The purpose of the present study was to evaluate the influence of alcohol administration on cocaine cue attentional bias using eye-tracking technology to directly measure attentional allocation. Methods Twenty current cocaine users completed a double-blind, placebo-controlled, within-subjects study that tested the effect of three doses of alcohol (0.00, 0.325, 0.65 g/kg alcohol) on cocaine cue attentional bias using the visual probe task with eye-tracking technology. The participant-rated and physiological effects of alcohol were also assessed. Results Participants displayed a robust cocaine cue attentional bias following both placebo and alcohol administration as measured by fixation time, but not response time. Alcohol administration did not influence cocaine cue attentional bias, but increased craving for cocaine in a dose dependent manner. Alcohol produced prototypic psychomotor and participant-rated effects. Conclusions Alcohol administration increases cocaine craving but not cocaine cue attentional bias. Alcohol-induced cocaine craving suggests that alcohol increases incentive motivation for cocaine but not the salience of cocaine-related cues. PMID:26331880

  3. Flexibility in task switching by monolinguals and bilinguals*

    PubMed Central

    WISEHEART, MELODY; VISWANATHAN, MYTHILI; BIALYSTOK, ELLEN

    2015-01-01

    Many bilinguals routinely switch between their languages, yet mixed evidence exists about the transfer of language switching skills to broader domains that require attentional control such as task switching. Monolingual and bilingual young adults performed a nonverbal task-switching paradigm in which they viewed colored pictures of animals and indicated either the animal or its color in response to a cue. Monolinguals and bilinguals performed similarly when switching between tasks (local switch cost) in a mixed-task block, but bilinguals demonstrated a smaller mixing effect (global switch cost) than monolinguals, indicating better ability to reconfigure stimulus–response associations. These results suggest that regular practice using multiple languages confers a broader executive function advantage shown as improved flexibility in task switching. PMID:26877705

  4. Dynamics in hybrid complex systems of switches and oscillators

    NASA Astrophysics Data System (ADS)

    Taylor, Dane; Fertig, Elana J.; Restrepo, Juan G.

    2013-09-01

    While considerable progress has been made in the analysis of large systems containing a single type of coupled dynamical component (e.g., coupled oscillators or coupled switches), systems containing diverse components (e.g., both oscillators and switches) have received much less attention. We analyze large, hybrid systems of interconnected Kuramoto oscillators and Hopfield switches with positive feedback. In this system, oscillator synchronization promotes switches to turn on. In turn, when switches turn on, they enhance the synchrony of the oscillators to which they are coupled. Depending on the choice of parameters, we find theoretically coexisting stable solutions with either (i) incoherent oscillators and all switches permanently off, (ii) synchronized oscillators and all switches permanently on, or (iii) synchronized oscillators and switches that periodically alternate between the on and off states. Numerical experiments confirm these predictions. We discuss how transitions between these steady state solutions can be onset deterministically through dynamic bifurcations or spontaneously due to finite-size fluctuations.

  5. Priming mortality salience: supraliminal, subliminal and "double-death" priming techniques.

    PubMed

    Mahoney, Melissa B; Saunders, Benjamin A; Cain, Nicole M

    2014-01-01

    The study examined whether successively presented subliminal and supraliminal morality salience primes ("double death" prime) would have a stronger influence on death thought accessibility than subliminal or supraliminal primes alone. A between-subjects 2 (subliminal prime/control) × 2 (supraliminal prime/control) design was used. The supraliminal prime prompted participants to answer questions about death. For the subliminal prime, the word death was presented outside of awareness. Both priming techniques differed significantly from a control in ability to elicit mortality salience. There was an interactive influence of both primes. Implications for unconscious neutral networks relating to death are discussed. PMID:24592974

  6. Attentional spreading in object-based attention.

    PubMed

    Richard, Ashleigh M; Lee, Hyunkyu; Vecera, Shaun P

    2008-08-01

    The authors investigated 2 effects of object-based attention: the spread of attention within an attended object and the prioritization of search across possible target locations within an attended object. Participants performed a flanker task in which the location of the task-relevant target was fixed and known to participants. A spreading attention account predicts that object-based attention will arise from the spread of attention through an attended object. A prioritization account predicts that there will be a small, if any, object-based effect because the location of the target is known in advance and objects are not required to prioritize the deployment of attentional search. The results suggested that object-based attention operates via the spread of attention within an object. PMID:18665730

  7. Switch Transcripts in Immunoglobulin Class Switching

    NASA Astrophysics Data System (ADS)

    Lorenz, Matthias; Jung, Steffen; Radbruch, Andreas

    1995-03-01

    B cells can exchange gene segments for the constant region of the immunoglobulin heavy chain, altering the class and effector function of the antibodies that they produce. Class switching is directed to distinct classes by cytokines, which induce transcription of the targeted DNA sequences. These transcripts are processed, resulting in spliced "switch" transcripts. Switch recombination can be directed to immunoglobulin G1 (IgG1) by the heterologous human metallothionein II_A promoter in mutant mice. Induction of the structurally conserved, spliced switch transcripts is sufficient to target switch recombination to IgG1, whereas transcription alone is not.

  8. A chaotic model of sustaining attention problem in attention deficit disorder

    NASA Astrophysics Data System (ADS)

    Baghdadi, G.; Jafari, S.; Sprott, J. C.; Towhidkhah, F.; Hashemi Golpayegani, M. R.

    2015-01-01

    The problem of keeping an attention level is one of the common symptoms of attention deficit disorder. Dopamine deficiency is introduced as one of the causes of this disorder. Based on some physiological facts about the attention control mechanism and chaos intermittency, a behavioral model is presented in this paper. This model represents the problem of undesired alternation of attention level, and can also suggest different valuable predictions about a possible cause of attention deficit disorder. The proposed model reveals that there is a possible interaction between different neurotransmitters which help the individual to adaptively inhibit the attention switching over time. The result of this study can be used to examine and develop a new practical and more appropriate treatment for the problem of sustaining attention.

  9. The Attention Cascade Model and Attentional Blink

    ERIC Educational Resources Information Center

    Shih, Shui-I

    2008-01-01

    An attention cascade model is proposed to account for attentional blinks in rapid serial visual presentation (RSVP) of stimuli. Data were collected using single characters in a single RSVP stream at 10 Hz [Shih, S., & Reeves, A. (2007). "Attentional capture in rapid serial visual presentation." "Spatial Vision", 20(4), 301-315], and single words,…

  10. Miniature intermittent contact switch

    NASA Technical Reports Server (NTRS)

    Sword, A.

    1972-01-01

    Design of electric switch for providing intermittent contact is presented. Switch consists of flexible conductor surrounding, but separated from, fixed conductor. Flexing of outside conductor to contact fixed conductor completes circuit. Advantage is small size of switch compared to standard switches.

  11. Latching relay switch assembly

    DOEpatents

    Duimstra, Frederick A.

    1991-01-01

    A latching relay switch assembly which includes a coil section and a switch or contact section. The coil section includes at least one permanent magnet and at least one electromagnet. The respective sections are, generally, arranged in separate locations or cavities in the assembly. The switch is latched by a permanent magnet assembly and selectively switched by an overriding electromagnetic assembly.

  12. Capture of attention to threatening stimuli without perceptual awareness

    PubMed Central

    Lin, Jeffrey Y.; Murray, Scott O.; Boynton, Geoffrey M.

    2009-01-01

    Summary Visual images that convey threatening information can automatically capture attention [1-4]. One example is an object looming in the direction of the observer—presumably because such a stimulus signals an impending collision [5]. A critical question for understanding the relationship between attention and conscious awareness is whether awareness is required for this type of prioritized attentional selection [6]. Although it has been suggested that visual spatial attention can only be affected by consciously perceived events [7], we show that automatic allocation of attention can occur even without conscious awareness of impending threat. We used a visual search task to show that a looming stimulus on a collision path with an observer captures attention but a looming stimulus on a near-miss path does not. Critically, observers were unaware of any difference between collision and near-miss stimuli even when explicitly asked to discriminate between them in separate experiments. These results counter traditional salience-based models of attentional capture, demonstrating that in the absence of perceptual awareness, the visual system can extract behaviorally relevant details from a visual scene and automatically categorize threatening versus non-threatening images at a level of precision beyond our conscious perceptual capabilities. PMID:19523828

  13. Attention maps in the brain

    PubMed Central

    Somers, David C.; Sheremata, Summer L.

    2014-01-01

    Over 20 distinct cerebral cortical areas contain spatial map representations of the visual field. These retinotopic, or visuotopic, cortical areas occur not only in the occipital lobe but also in the parietal, temporal, and frontal lobes. The cognitive influences of visuospatial attention operate via these cortical maps and can support selection of multiple objects at the same time. In early visual cortical areas, spatial attention enhances responses of selected items and diminishes the responses to distracting items. In higher order cortex, the maps support a spatial indexing role, keeping track of the items to be attended. These maps also support visual short-term memory (VSTM) representations. In each hemisphere, all the known maps respond selectively to stimuli presented within the contralateral visual field. However, a hemispheric asymmetry emerges when the attentional or VSTM demands of a task become significant. In the parietal lobe, the right hemisphere visuotopic maps switch from coding only contralateral visual targets to coding memory and attention targets across the entire visual field. This emergent asymmetry has important implications for understanding hemispatial neglect syndrome, and supports a dynamic network form of the representational model of neglect. PMID:25089167

  14. Enhanced distraction by magnocellular salience signals in schizophrenia.

    PubMed

    Leonard, Carly J; Robinson, Benjamin M; Hahn, Britta; Gold, James M; Luck, Steven J

    2014-04-01

    Research on schizophrenia has provided evidence of both impaired attentional control and dysfunctional magnocellular sensory processing. The present study tested the hypothesis that these impairments may be related, such that people with schizophrenia would be differentially distracted by stimuli that strongly activate the magnocellular pathway. To accomplish this, we used a visual attention paradigm from the basic cognitive neuroscience literature designed to assess the capture of attention by salient but irrelevant stimuli. Participants searched for a target shape in an array of non-target shapes. On some trials, a salient distractor was presented that either selectively activated the parvocellular system (parvo-biased distractors) or activated both the magnocellular and parvocellular systems (magno+parvo distractors). For both manual reaction times and eye movement measures, the magno+parvo distractors captured attention more strongly than the parvo-biased distractors in people with schizophrenia, but the opposite pattern was observed in matched healthy control participants. These results indicate that attentional control deficits in schizophrenia may arise, at least in part, by means of an interaction with magnocellular sensory dysfunction. PMID:24561035

  15. The evolution of mating type switching.

    PubMed

    Hadjivasiliou, Zena; Pomiankowski, Andrew; Kuijper, Bram

    2016-07-01

    Predictions about the evolution of sex determination mechanisms have mainly focused on animals and plants, whereas unicellular eukaryotes such as fungi and ciliates have received little attention. Many taxa within the latter groups can stochastically switch their mating type identity during vegetative growth. Here, we investigate the hypothesis that mating type switching overcomes distortions in the distribution of mating types due to drift during asexual growth. Using a computational model, we show that smaller population size, longer vegetative periods and more mating types lead to greater distortions in the distribution of mating types. However, the impact of these parameters on optimal switching rates is not straightforward. We find that longer vegetative periods cause reductions and considerable fluctuations in the switching rate over time. Smaller population size increases the strength of selection for switching but has little impact on the switching rate itself. The number of mating types decreases switching rates when gametes can freely sample each other, but increases switching rates when there is selection for speedy mating. We discuss our results in light of empirical work and propose new experiments that could further our understanding of sexuality in isogamous eukaryotes. PMID:27271362

  16. A sub-1-volt nanoelectromechanical switching device

    NASA Astrophysics Data System (ADS)

    Lee, Jeong Oen; Song, Yong-Ha; Kim, Min-Wu; Kang, Min-Ho; Oh, Jae-Sub; Yang, Hyun-Ho; Yoon, Jun-Bo

    2013-01-01

    Nanoelectromechanical (NEM) switches have received widespread attention as promising candidates in the drive to surmount the physical limitations currently faced by complementary metal oxide semiconductor technology. The NEM switch has demonstrated superior characteristics including quasi-zero leakage behaviour, excellent density capability and operation in harsh environments. However, an unacceptably high operating voltage (4-20 V) has posed a major obstacle in the practical use of the NEM switch in low-power integrated circuits. To utilize the NEM switch widely as a core device component in ultralow power applications, the operation voltage needs to be reduced to 1 V or below. However, sub-1 V actuation has not yet been demonstrated because of fabrication difficulties and irreversible switching failure caused by surface adhesion. Here, we report the sub-1 V operation of a NEM switch through the introduction of a novel pipe clip device structure and an effective air gap fabrication technique. This achievement is primarily attributed to the incorporation of a 4-nm-thick air gap, which is the smallest reported so far for a NEM switch generated using a `top-down' approach. Our structure and process can potentially be utilized in various nanogap-related applications, including NEM switch-based ultralow-power integrated circuits, NEM resonators, nanogap electrodes for scientific research and sensors.

  17. Radiation hard vacuum switch

    DOEpatents

    Boettcher, Gordon E.

    1990-03-06

    A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

  18. Radiation hard vacuum switch

    DOEpatents

    Boettcher, Gordon E.

    1990-01-01

    A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

  19. Dual Low-Rank Pursuit: Learning Salient Features for Saliency Detection.

    PubMed

    Lang, Congyan; Feng, Jiashi; Feng, Songhe; Wang, Jingdong; Yan, Shuicheng

    2016-06-01

    Saliency detection is an important procedure for machines to understand visual world as humans do. In this paper, we consider a specific saliency detection problem of predicting human eye fixations when they freely view natural images, and propose a novel dual low-rank pursuit (DLRP) method. DLRP learns saliency-aware feature transformations by utilizing available supervision information and constructs discriminative bases for effectively detecting human fixation points under the popular low-rank and sparsity-pursuit framework. Benefiting from the embedded high-level information in the supervised learning process, DLRP is able to predict fixations accurately without performing the expensive object segmentation as in the previous works. Comprehensive experiments clearly show the superiority of the proposed DLRP method over the established state-of-the-art methods. We also empirically demonstrate that DLRP provides stronger generalization performance across different data sets and inherits the advantages of both the bottom-up- and top-down-based saliency detection methods. PMID:27046853

  20. Differing Levels of Gender Salience in Preschool Classrooms: Effects on Children's Gender Attitudes and Intergroup Bias

    ERIC Educational Resources Information Center

    Hilliard, Lacey J.; Liben, Lynn S.

    2010-01-01

    Developmental intergroup theory posits that when environments make social-group membership salient, children will be particularly likely to apply categorization processes to social groups, thereby increasing stereotypes and prejudices. To test the predicted impact of environmental gender salience, 3- to 5-year-old children (N = 57) completed…

  1. Element Salience as a Predictor of Item Difficulty for Raven's Progressive Matrices

    ERIC Educational Resources Information Center

    Meo, Maria; Roberts, Maxwell J.; Marucci, Francesco S.

    2007-01-01

    Raven's Progressive Matrices is a frequently used intelligence test, and it has been suggested that the major determinant of difficulty for each item is its numbers of elements and rules, and its rule complexity. The current study investigated another potential source of difficulty--element salience--items are harder where their elements are…

  2. Researcher Effects on Mortality Salience Research: A Meta-Analytic Moderator Analysis

    ERIC Educational Resources Information Center

    Yen, Chih-Long; Cheng, Chung-Ping

    2013-01-01

    A recent meta-analysis of 164 terror management theory (TMT) papers indicated that mortality salience (MS) yields substantial effects (r = 0.35) on worldview and self-esteem-related dependent variables (B. L. Burke, A. Martens, & E. H. Faucher, 2010). This study reanalyzed the data to explore the researcher effects of TMT. By cluster-analyzing…

  3. Relative Saliency in Change Signals Affects Perceptual Comparison and Decision Processes in Change Detection

    ERIC Educational Resources Information Center

    Yang, Cheng-Ta

    2011-01-01

    Change detection requires perceptual comparison and decision processes on different features of multiattribute objects. How relative salience between two feature-changes influences the processes has not been addressed. This study used the systems factorial technology to investigate the processes when detecting changes in a Gabor patch with visual…

  4. The Role of Accent Salience and Joint Accent Structure in Meter Perception

    ERIC Educational Resources Information Center

    Ellis, Robert J.; Jones, Mari R.

    2009-01-01

    Previous research indicates that temporal accents (TAs; accents due to time changes) play a strong role in meter perception, but evidence favoring a role for melodic accents (MAs; accents due to pitch changes) is mixed. The authors claim that this mixed support for MAs is the result of a failure to control for accent salience and addressed this…

  5. Movement or Goal: Goal Salience and Verbal Cues Affect Preschoolers' Imitation of Action Components

    ERIC Educational Resources Information Center

    Elsner, Birgit; Pfeifer, Caroline

    2012-01-01

    The impact of goal salience and verbal cues given by the model on 3- to 5-year-olds' reproduction of action components (movement or goal) was investigated in an imitation choice task. Preschoolers watched an experimenter moving a puppet up or down a ramp, terminating at one of two target objects. The target objects were either differently colored…

  6. Defensive or Existential Religious Orientations and Mortality Salience Hypothesis: Using Conservatism as a Dependent Measure

    ERIC Educational Resources Information Center

    Koca-Atabey, Mujde; Oner-Ozkan, Bengi

    2011-01-01

    The study examined the relationship between the defensive versus existential religious orientation and mortality salience hypothesis in a country where the predominant type of religion is Islam. It was predicted that the mortality reactions of participants would not differ in accordance with their religious orientations within a Muslim sample. The…

  7. Learning-Based Visual Saliency Model for Detecting Diabetic Macular Edema in Retinal Image.

    PubMed

    Zou, Xiaochun; Zhao, Xinbo; Yang, Yongjia; Li, Na

    2016-01-01

    This paper brings forth a learning-based visual saliency model method for detecting diagnostic diabetic macular edema (DME) regions of interest (RoIs) in retinal image. The method introduces the cognitive process of visual selection of relevant regions that arises during an ophthalmologist's image examination. To record the process, we collected eye-tracking data of 10 ophthalmologists on 100 images and used this database as training and testing examples. Based on analysis, two properties (Feature Property and Position Property) can be derived and combined by a simple intersection operation to obtain a saliency map. The Feature Property is implemented by support vector machine (SVM) technique using the diagnosis as supervisor; Position Property is implemented by statistical analysis of training samples. This technique is able to learn the preferences of ophthalmologist visual behavior while simultaneously considering feature uniqueness. The method was evaluated using three popular saliency model evaluation scores (AUC, EMD, and SS) and three quality measurements (classical sensitivity, specificity, and Youden's J statistic). The proposed method outperforms 8 state-of-the-art saliency models and 3 salient region detection approaches devised for natural images. Furthermore, our model successfully detects the DME RoIs in retinal image without sophisticated image processing such as region segmentation. PMID:26884750

  8. Isolating the Incentive Salience of Reward-Associated Stimuli: Value, Choice, and Persistence

    ERIC Educational Resources Information Center

    Beckmann, Joshua S.; Chow, Jonathan J.

    2015-01-01

    Sign- and goal-tracking are differentially associated with drug abuse-related behavior. Recently, it has been hypothesized that sign- and goal-tracking behavior are mediated by different neurobehavioral valuation systems, including differential incentive salience attribution. Herein, we used different conditioned stimuli to preferentially elicit…

  9. The Effects of Prototypicality and Cultural Salience on Perceptions of People.

    ERIC Educational Resources Information Center

    Forgas, Joseph P.

    1983-01-01

    Studied person prototypes within a subcultural milieu and the influence of cultural salience on recall memory, predictions, and impression formation in two studies of college students. Results suggested that multiple information-processing strategies are used in person perception, influenced by normative and cultural variables. (WAS)

  10. A Comparison between Element Salience versus Context as Item Difficulty Factors in Raven's Matrices

    ERIC Educational Resources Information Center

    Perez-Salas, Claudia P.; Streiner, David L.; Roberts, Maxwell J.

    2012-01-01

    The nature of contextual facilitation effects for items derived from Raven's Progressive Matrices was investigated in two experiments. For these, the original matrices were modified, creating either abstract versions with high element salience, or versions which comprised realistic entities set in familiar contexts. In order to replicate and…

  11. Two-scale image fusion of visible and infrared images using saliency detection

    NASA Astrophysics Data System (ADS)

    Bavirisetti, Durga Prasad; Dhuli, Ravindra

    2016-05-01

    Military, navigation and concealed weapon detection need different imaging modalities such as visible and infrared to monitor a targeted scene. These modalities provide complementary information. For better situation awareness, complementary information of these images has to be integrated into a single image. Image fusion is the process of integrating complementary source information into a composite image. In this paper, we propose a new image fusion method based on saliency detection and two-scale image decomposition. This method is beneficial because the visual saliency extraction process introduced in this paper can highlight the saliency information of source images very well. A new weight map construction process based on visual saliency is proposed. This process is able to integrate the visually significant information of source images into the fused image. In contrast to most of the multi-scale image fusion techniques, proposed technique uses only two-scale image decomposition. So it is fast and efficient. Our method is tested on several image pairs and is evaluated qualitatively by visual inspection and quantitatively using objective fusion metrics. Outcomes of the proposed method are compared with the state-of-art multi-scale fusion techniques. Results reveal that the proposed method performance is comparable or superior to the existing methods.

  12. Subjective and Objective Parameters Determining "Salience" in Long-Term Dialect Accommodation.

    ERIC Educational Resources Information Center

    Auer, Peter; Barden, Birgit; Grosskopf, Beate

    1998-01-01

    Presents results of a longitudinal study on long-term dialect accommodation in a German dialect setting. An important model of explaining which linguistic structures undergo such convergence and which do not makes use of the notion of "salience." (Author/VWL)

  13. Reconciling Saliency and Object Center-Bias Hypotheses in Explaining Free-Viewing Fixations.

    PubMed

    Borji, Ali; Tanner, James

    2016-06-01

    Predicting where people look in natural scenes has attracted a lot of interest in computer vision and computational neuroscience over the past two decades. Two seemingly contrasting categories of cues have been proposed to influence where people look: 1) low-level image saliency and 2) high-level semantic information. Our first contribution is to take a detailed look at these cues to confirm the hypothesis proposed by Henderson and Nuthmann and Henderson that observers tend to look at the center of objects. We analyzed fixation data for scene free-viewing over 17 observers on 60 object-annotated images with various types of objects. Images contained different types of scenes, such as natural scenes, line drawings, and 3-D rendered scenes. Our second contribution is to propose a simple combined model of low-level saliency and object center bias that outperforms each individual component significantly over our data, as well as on the Object and Semantic Images and Eye-tracking data set by Xu et al. The results reconcile saliency with object center-bias hypotheses and highlight that both types of cues are important in guiding fixations. Our work opens new directions to understand strategies that humans use in observing scenes and objects, and demonstrates the construction of combined models of low-level saliency and high-level object-based information. PMID:26452292

  14. Don't fear the reaper: trait death anxiety, mortality salience, and occupational health.

    PubMed

    Sliter, Michael T; Sinclair, Robert R; Yuan, Zhenyu; Mohr, Cynthia D

    2014-07-01

    Despite multiple calls for research, there has been little effort to incorporate topics regarding mortality salience and death anxiety into workplace literature. As such, the goals of the current study were to (a) examine how trait differences in death anxiety relate to employee occupational health outcomes and (b) examine how death anxiety might exacerbate the negative effects of mortality salience cues experienced at work. In Study 1, we examined how death anxiety affected nurses in a multitime point survey. These results showed that trait death anxiety was associated with increased burnout and reduced engagement and that death anxiety further exacerbated the relationship between mortality salience cues (e.g., dealing with injured and dying patients) and burnout. These results were replicated and extended in Study 2, which examined the impact of death anxiety in firefighters. In this multitime point study, death anxiety related to burnout, engagement, and absenteeism. The results further showed that death anxiety moderated the relationship between mortality cues and burnout, where people high in trait death anxiety experience higher levels of burnout as a result of mortality cues than people lower in death anxiety. Across the 2 studies, despite differences in the methods (e.g., time lag; measures), the effect sizes and the form of the significant interactions were quite similar. Overall, these results highlight the importance of understanding death anxiety in the workplace, particularly in occupations where mortality salience cues are common. We discuss recommendations, such as death education and vocational counseling, and provide some avenues for future research. PMID:24490968

  15. Active Teaching Strategies for a Sense of Salience: End-of-Life Communication

    ERIC Educational Resources Information Center

    Kopp, Mary L.

    2013-01-01

    This study compared active teaching strategies with passive lecture by evaluating cognitive, affective, and psychomotor learning outcomes, while highlighting end-of-life communication in nursing education. The problem addressed was twofold: First, passive lecture prevents transfer to situational decision-making, or a sense of salience (Benner,…

  16. Learning-Based Visual Saliency Model for Detecting Diabetic Macular Edema in Retinal Image

    PubMed Central

    Zou, Xiaochun; Zhao, Xinbo; Yang, Yongjia; Li, Na

    2016-01-01

    This paper brings forth a learning-based visual saliency model method for detecting diagnostic diabetic macular edema (DME) regions of interest (RoIs) in retinal image. The method introduces the cognitive process of visual selection of relevant regions that arises during an ophthalmologist's image examination. To record the process, we collected eye-tracking data of 10 ophthalmologists on 100 images and used this database as training and testing examples. Based on analysis, two properties (Feature Property and Position Property) can be derived and combined by a simple intersection operation to obtain a saliency map. The Feature Property is implemented by support vector machine (SVM) technique using the diagnosis as supervisor; Position Property is implemented by statistical analysis of training samples. This technique is able to learn the preferences of ophthalmologist visual behavior while simultaneously considering feature uniqueness. The method was evaluated using three popular saliency model evaluation scores (AUC, EMD, and SS) and three quality measurements (classical sensitivity, specificity, and Youden's J statistic). The proposed method outperforms 8 state-of-the-art saliency models and 3 salient region detection approaches devised for natural images. Furthermore, our model successfully detects the DME RoIs in retinal image without sophisticated image processing such as region segmentation. PMID:26884750

  17. Evolutionary Trends and the Salience Bias (with Apologies to Oil Tankers, Karl Marx, and Others).

    ERIC Educational Resources Information Center

    McShea, Daniel W.

    1994-01-01

    Examines evolutionary trends, specifically trends in size, complexity, and fitness. Notes that documentation of these trends consists of either long lists of cases, or descriptions of a small number of salient cases. Proposes the use of random samples to avoid this "saliency bias." (SR)

  18. Life Role Salience Dimensions and Mental Health Outcomes among Female Expatriate Spouses in Turkey

    ERIC Educational Resources Information Center

    Bikos, Lynette H.; Kocheleva, Julia

    2013-01-01

    Using life role salience theory, we investigated the extent to which occupational, parental, marital, and home care roles explained mental health outcomes among female expatriate spouses. Participants (N = 86) were from English-speaking Northern American or Western European countries; the average age was 38. Results of a two-way within-subject…

  19. Effects of Communication Mode and Salience on Recasts: A First Exposure Study

    ERIC Educational Resources Information Center

    Yilmaz, Yucel; Yuksel, Dogan

    2011-01-01

    This article reports on a study that investigated whether the extent to which learners benefit from recasts on two Turkish morphemes differ depending on communication mode--i.e. Face-to-Face Communication (F2FC) and text-based Synchronous Computer-Mediated Communication (SCMC)--and/or the salience of the target structure (i.e. salient and…

  20. From prediction error to incentive salience: mesolimbic computation of reward motivation

    PubMed Central

    Berridge, Kent C.

    2011-01-01

    Reward contains separable psychological components of learning, incentive motivation and pleasure. Most computational models have focused only on the learning component of reward, but the motivational component is equally important in reward circuitry, and even more directly controls behavior. Modeling the motivational component requires recognition of additional control factors besides learning. Here I will discuss how mesocorticolimbic mechanisms generate the motivation component of incentive salience. Incentive salience takes Pavlovian learning and memory as one input and as an equally important input takes neurobiological state factors (e.g., drug states, appetite states, satiety states) that can vary independently of learning. Neurobiological state changes can produce unlearned fluctuations or even reversals in the ability of a previously-learned reward cue to trigger motivation. Such fluctuations in cue-triggered motivation can dramatically depart from all previously learned values about the associated reward outcome. Thus a consequence of the difference between incentive salience and learning can be to decouple cue-triggered motivation of the moment from previously learned values of how good the associated reward has been in the past. Another consequence can be to produce irrationally strong motivation urges that are not justified by any memories of previous reward values (and without distorting associative predictions of future reward value). Such irrationally strong motivation may be especially problematic in addiction. To comprehend these phenomena, future models of mesocorticolimbic reward function should address the neurobiological state factors that participate to control generation of incentive salience. PMID:22487042

  1. Salience Effects: L2 Sentence Production as a Window on L1 Speech Planning

    ERIC Educational Resources Information Center

    Antón-Méndez, Inés; Gerfen, Chip; Ramos, Miguel

    2016-01-01

    Salience influences grammatical structure during production in a language-dependent manner because different languages afford different options to satisfy preferences. During production, speakers may always try to satisfy all syntactic encoding preferences (e.g., salient entities to be mentioned early, themes to be assigned the syntactic function…

  2. Quantifying Individual Variation in the Propensity to Attribute Incentive Salience to Reward Cues

    PubMed Central

    Meyer, Paul J.; Lovic, Vedran; Saunders, Benjamin T.; Yager, Lindsay M.; Flagel, Shelly B.; Morrow, Jonathan D.; Robinson, Terry E.

    2012-01-01

    If reward-associated cues acquire the properties of incentive stimuli they can come to powerfully control behavior, and potentially promote maladaptive behavior. Pavlovian incentive stimuli are defined as stimuli that have three fundamental properties: they are attractive, they are themselves desired, and they can spur instrumental actions. We have found, however, that there is considerable individual variation in the extent to which animals attribute Pavlovian incentive motivational properties (“incentive salience”) to reward cues. The purpose of this paper was to develop criteria for identifying and classifying individuals based on their propensity to attribute incentive salience to reward cues. To do this, we conducted a meta-analysis of a large sample of rats (N = 1,878) subjected to a classic Pavlovian conditioning procedure. We then used the propensity of animals to approach a cue predictive of reward (one index of the extent to which the cue was attributed with incentive salience), to characterize two behavioral phenotypes in this population: animals that approached the cue (“sign-trackers”) vs. others that approached the location of reward delivery (“goal-trackers”). This variation in Pavlovian approach behavior predicted other behavioral indices of the propensity to attribute incentive salience to reward cues. Thus, the procedures reported here should be useful for making comparisons across studies and for assessing individual variation in incentive salience attribution in small samples of the population, or even for classifying single animals. PMID:22761718

  3. Hemispheric Asymmetries in Processing L1 and L2 Idioms: Effects of Salience and Context

    ERIC Educational Resources Information Center

    Cieslicka, Anna B.; Heredia, Roberto R.

    2011-01-01

    This study investigates the contribution of the left and right hemispheres to the comprehension of bilingual figurative language and the joint effects of salience and context on the differential cerebral involvement in idiom processing. The divided visual field and the lexical decision priming paradigms were employed to examine the activation of…

  4. Small target pre-detection with an attention mechanism

    NASA Astrophysics Data System (ADS)

    Wang, Yuehuan; Zhang, Tianxu; Wang, Guoyou

    2002-04-01

    We introduce the concept of predetection based on an attention mechanism to improve the efficiency of small-target detection by limiting the image region of detection. According to the characteristics of small-target detection, local contrast is taken as the only feature in predetection and a nonlinear sampling model is adopted to make the predetection adaptive to detect small targets with different area sizes. To simplify the predetection itself and decrease the false alarm probability, neighboring nodes in the sampling grid are used to generate a saliency map, and a short-term memory is adopted to accelerate the `pop-out' of targets. We discuss the fact that the proposed approach is simple enough in computational complexity. In addition, even in a cluttered background, attention can be led to targets in a satisfying few iterations, which ensures that the detection efficiency will not be decreased due to false alarms. Experimental results are presented to demonstrate the applicability of the approach.

  5. Through a barn owl's eyes: interactions between scene content and visual attention.

    PubMed

    Ohayon, Shay; Harmening, Wolf; Wagner, Hermann; Rivlin, Ehud

    2008-02-01

    In this study we investigated visual attention properties of freely behaving barn owls, using a miniature wireless camera attached to their heads. The tubular eye structure of barn owls makes them ideal subjects for this research since it limits their eye movements. Video sequences recorded from the owl's point of view capture part of the visual scene as seen by the owl. Automated analysis of video sequences revealed that during an active search task, owls repeatedly and consistently direct their gaze in a way that brings objects of interest to a specific retinal location (retinal fixation area). Using a projective model that captures the geometry between the eye and the camera, we recovered the corresponding location in the recorded images (image fixation area). Recording in various types of environments (aviary, office, outdoors) revealed significant statistical differences of low level image properties at the image fixation area compared to values extracted at random image patches. These differences are in agreement with results obtained in primates in similar studies. To investigate the role of saliency and its contribution to drawing the owl's attention, we used a popular bottom-up computational model. Saliency values at the image fixation area were typically greater than at random patches, yet were only 20% out of the maximal saliency value, suggesting a top-down modulation of gaze control. PMID:18066583

  6. Trends in the salience of data collected in a multi user virtual environment: An exploratory study

    NASA Astrophysics Data System (ADS)

    Tutwiler, M. Shane

    In this study, by exploring patterns in the degree of physical salience of the data the students collected, I investigated the relationship between the level of students' tendency to frame explanations in terms of complex patterns and evidence of how they attend to and select data in support of their developing understandings of causal relationships. I accomplished this by analyzing longitudinal data collected as part of a larger study of 143 7th grade students (clustered within 36 teams, 5 teachers, and 2 schools in the same Northeastern school district) as they navigated and collected data in an ecosystems-based multi-user virtual environment curriculum known as the EcoMUVE Pond module (Metcalf, Kamarainen, Tutwiler, Grotzer, Dede, 2011) . Using individual growth modeling (Singer & Willett, 2003) I found no direct link between student pre-intervention tendency to offer explanations containing complex causal components and patterns of physical salience-driven data collection (average physical salience level, number of low physical salience data points collected, and proportion of low physical salience data points collected), though prior science content knowledge did affect the initial status and rate of change of outcomes in the average physical salience level and proportion of low physical salience data collected over time. The findings of this study suggest two issues for consideration about the use of MUVEs to study student data collection behaviors in complex spaces. Firstly, the structure of the curriculum in which the MUVE is embedded might have a direct effect on what types of data students choose to collect. This undercuts our ability to make inferences about student-driven decisions to collect specific types of data, and suggests that a more open-ended curricular model might be better suited to this type of inquiry. Secondly, differences between teachers' choices in how to facilitate the units likely contribute to the variance in student data collection

  7. Perceptual Salience and Reward Both Influence Feedback-Related Neural Activity Arising from Choice.

    PubMed

    Lou, Bin; Hsu, Wha-Yin; Sajda, Paul

    2015-09-23

    For day-to-day decisions, multiple factors influence our choice between alternatives. Two dimensions of decision making that substantially affect choice are the objective perceptual properties of the stimulus (e.g., salience) and its subjective value. Here we measure EEGs in human subjects to relate their feedback-evoked EEG responses to estimates of prediction error given a neurally derived expected value for each trial. Unlike in traditional reinforcement learning paradigms, in our experiment the reward itself is not probabilistic; rather, it is a fixed value, which, when combined with the variable stimulus salience, yields uncertainty in the choice. We find that feedback-evoked event-related potentials (ERPs), specifically those classically termed feedback-related negativity, are modulated by both the reward level and stimulus salience. Using single-trial analysis of the EEG, we show stimulus-locked EEG components reflecting perceived stimulus salience can be combined with the level of reward to create an estimate of expected reward. This expected reward is used to form a prediction error that correlates with the trial-by-trial variability of the feedback ERPs for negative, but not positive, feedback. This suggests that the valence of prediction error is more important than the valence of the actual feedback, since only positive rewards were delivered in the experiment (no penalty or loss). Finally, we show that these subjectively defined prediction errors are informative of the riskiness of the subject's choice on the subsequent trial. In summary, our work shows that neural correlates of stimulus salience interact with value information to yield neural representations of subjective expected reward. Significance statement: How we make perceptual decisions depends on sensory evidence and the value of our options. These two factors often interact to yield subjective decisions; i.e., individuals integrate sensory evidence and value to form their own estimates of

  8. Perceptual Salience and Reward Both Influence Feedback-Related Neural Activity Arising from Choice

    PubMed Central

    Lou, Bin; Hsu, Wha-Yin

    2015-01-01

    For day-to-day decisions, multiple factors influence our choice between alternatives. Two dimensions of decision making that substantially affect choice are the objective perceptual properties of the stimulus (e.g., salience) and its subjective value. Here we measure EEGs in human subjects to relate their feedback-evoked EEG responses to estimates of prediction error given a neurally derived expected value for each trial. Unlike in traditional reinforcement learning paradigms, in our experiment the reward itself is not probabilistic; rather, it is a fixed value, which, when combined with the variable stimulus salience, yields uncertainty in the choice. We find that feedback-evoked event-related potentials (ERPs), specifically those classically termed feedback-related negativity, are modulated by both the reward level and stimulus salience. Using single-trial analysis of the EEG, we show stimulus-locked EEG components reflecting perceived stimulus salience can be combined with the level of reward to create an estimate of expected reward. This expected reward is used to form a prediction error that correlates with the trial-by-trial variability of the feedback ERPs for negative, but not positive, feedback. This suggests that the valence of prediction error is more important than the valence of the actual feedback, since only positive rewards were delivered in the experiment (no penalty or loss). Finally, we show that these subjectively defined prediction errors are informative of the riskiness of the subject's choice on the subsequent trial. In summary, our work shows that neural correlates of stimulus salience interact with value information to yield neural representations of subjective expected reward. SIGNIFICANCE STATEMENT How we make perceptual decisions depends on sensory evidence and the value of our options. These two factors often interact to yield subjective decisions; i.e., individuals integrate sensory evidence and value to form their own estimates of

  9. Modeling eye movements in visual agnosia with a saliency map approach: bottom-up guidance or top-down strategy?

    PubMed

    Foulsham, Tom; Barton, Jason J S; Kingstone, Alan; Dewhurst, Richard; Underwood, Geoffrey

    2011-08-01

    Two recent papers (Foulsham, Barton, Kingstone, Dewhurst, & Underwood, 2009; Mannan, Kennard, & Husain, 2009) report that neuropsychological patients with a profound object recognition problem (visual agnosic subjects) show differences from healthy observers in the way their eye movements are controlled when looking at images. The interpretation of these papers is that eye movements can be modeled as the selection of points on a saliency map, and that agnosic subjects show an increased reliance on visual saliency, i.e., brightness and contrast in low-level stimulus features. Here we review this approach and present new data from our own experiments with an agnosic patient that quantifies the relationship between saliency and fixation location. In addition, we consider whether the perceptual difficulties of individual patients might be modeled by selectively weighting the different features involved in a saliency map. Our data indicate that saliency is not always a good predictor of fixation in agnosia: even for our agnosic subject, as for normal observers, the saliency-fixation relationship varied as a function of the task. This means that top-down processes still have a significant effect on the earliest stages of scanning in the setting of visual agnosia, indicating severe limitations for the saliency map model. Top-down, active strategies-which are the hallmark of our human visual system-play a vital role in eye movement control, whether we know what we are looking at or not. PMID:21316191

  10. The role of attention in the academic attainment of children with autism spectrum disorder.

    PubMed

    May, Tamara; Rinehart, Nicole; Wilding, John; Cornish, Kim

    2013-09-01

    Academic attainment in children with Autism Spectrum Disorder (ASD) is under-studied, with associated factors largely undetermined. Parent-reported attention symptoms, attentional-switching and sustained-attention tasks were examined to determine relationships with mathematics and reading attainment in 124 children aged 7-12 years; sixty-four with high-functioning ASD, half girls, and sixty age- and gender-matched typical children (TYP). With full-scale IQ controlled there were no differences in mathematics, reading, attentional switching or sustained attention. In regression analysis, attentional switching was related to mathematics achievement in ASD but not TYP children. Findings highlight attentional switching difficulties are linked with poorer mathematics outcomes in ASD. PMID:23378062

  11. Attention Difficulties and Mood-Related Ruminative Response Style in Adolescents with Unipolar Depression

    ERIC Educational Resources Information Center

    Wilkinson, Paul O.; Goodyer, Ian M.

    2006-01-01

    Background: Depressed adults may show impairment in switching attention from one task to another. Rumination on negative thoughts is associated with the onset and persistence of depressive episodes. It is unclear if such mood-related ruminations are specifically associated with slowed ability in switching attention from one task to another.…

  12. Topologically Reorganized Connectivity Architecture of Default-Mode, Executive-Control, and Salience Networks across Working Memory Task Loads.

    PubMed

    Liang, Xia; Zou, Qihong; He, Yong; Yang, Yihong

    2016-04-01

    The human brain is topologically organized into a set of spatially distributed, functionally specific networks. Of these networks, the default-mode network (DMN), executive-control network (ECN), and salience network (SN) have received the most attention recently for their vital roles in cognitive functions. However, very little is known about whether and how the interactions within and between these 3 networks would be modulated by cognitive demands. Here, we employed graph-based modularity analysis to identify the DMN, ECN, and SN during an N-back working memory (WM) task and further investigated the modulation of intra- and inter-network interactions at different cognitive loads. As the task load elevated, functional connectivity decreased within the DMN while increased within the ECN, and the SN connected more with both the DMN and ECN. Within-network connectivity of the ventral and dorsal posterior cingulate cortex was differentially modulated by cognitive load. Further, the superior parietal regions in the ECN showed increased internetwork connections at higher WM loads, and these increases correlated positively with WM task performance. Together, these findings advance our understanding of dynamic integrations of specialized brain systems in response to cognitive demands and may serve as a baseline for assessing potential disruptions of these interactions in pathological conditions. PMID:25596593

  13. The Role of Code-Switching in Bilingual Creativity

    ERIC Educational Resources Information Center

    Kharkhurin, Anatoliy V.; Wei, Li

    2015-01-01

    This study further explores the theme of bilingual creativity with the present focus on code-switching. Specifically, it investigates whether code-switching practice has an impact on creativity. In line with the previous research, selective attention was proposed as a potential cognitive mechanism, which on the one hand would benefit from…

  14. Salience Assignment for Multiple-Instance Data and Its Application to Crop Yield Prediction

    NASA Technical Reports Server (NTRS)

    Wagstaff, Kiri L.; Lane, Terran

    2010-01-01

    An algorithm was developed to generate crop yield predictions from orbital remote sensing observations, by analyzing thousands of pixels per county and the associated historical crop yield data for those counties. The algorithm determines which pixels contain which crop. Since each known yield value is associated with thousands of individual pixels, this is a multiple instance learning problem. Because individual crop growth is related to the resulting yield, this relationship has been leveraged to identify pixels that are individually related to corn, wheat, cotton, and soybean yield. Those that have the strongest relationship to a given crop s yield values are most likely to contain fields with that crop. Remote sensing time series data (a new observation every 8 days) was examined for each pixel, which contains information for that pixel s growth curve, peak greenness, and other relevant features. An alternating-projection (AP) technique was used to first estimate the "salience" of each pixel, with respect to the given target (crop yield), and then those estimates were used to build a regression model that relates input data (remote sensing observations) to the target. This is achieved by constructing an exemplar for each crop in each county that is a weighted average of all the pixels within the county; the pixels are weighted according to the salience values. The new regression model estimate then informs the next estimate of the salience values. By iterating between these two steps, the algorithm converges to a stable estimate of both the salience of each pixel and the regression model. The salience values indicate which pixels are most relevant to each crop under consideration.

  15. Trading off stimulus salience for identity: A cueing approach to disentangle visual selection strategies.

    PubMed

    Paoletti, Davide; Weaver, Matthew D; Braun, Christoph; van Zoest, Wieske

    2015-08-01

    Recent studies show that time plays a primary role in determining whether visual selection is influenced by stimulus salience or guided by observers' intentions. Accordingly, when a response is made seems critically important in defining the outcome of selection. The present study investigates whether observers are able to control the timing of selection and regulate the trade-off between stimulus- and goal-driven influences. One experiment was conducted in which participants were asked to make a saccade to the target, a tilted bar embedded in a matrix of vertical lines. An additional distractor, more or less salient than the target, was presented concurrently with the search display. To manipulate when in time the response was given we cued participants before each trial to be either fast or accurate. Participants received periodic feedback regarding performance speed and accuracy. The results showed participants were able to control the timing of selection: the distribution of responses was relatively fast or slow depending on the cue. Performance in the fast-cue condition appeared to be primarily driven by stimulus salience, while in the accurate-cue condition saccades were guided by the search template. Examining the distribution of responses that temporally overlapped between the two cue conditions revealed a main effect of cue. This suggests the cue had an additional benefit to performance independent of the effect of salience. These findings show that although early selection may be constrained by stimulus salience, observers are flexible in guiding the 'when' signal and consequently establishing a trade-off between saliency and identity. PMID:25152318

  16. The Penefit of Salience: Salient Accented, but Not Unaccented Words Reveal Accent Adaptation Effects

    PubMed Central

    Grohe, Ann-Kathrin; Weber, Andrea

    2016-01-01

    In two eye-tracking experiments, the effects of salience in accent training and speech accentedness on spoken-word recognition were investigated. Salience was expected to increase a stimulus' prominence and therefore promote learning. A training-test paradigm was used on native German participants utilizing an artificial German accent. Salience was elicited by two different criteria: production and listening training as a subjective criterion and accented (Experiment 1) and canonical test words (Experiment 2) as an objective criterion. During training in Experiment 1, participants either read single German words out loud and deliberately devoiced initial voiced stop consonants (e.g., Balken—“beam” pronounced as *Palken), or they listened to pre-recorded words with the same accent. In a subsequent eye-tracking experiment, looks to auditorily presented target words with the accent were analyzed. Participants from both training conditions fixated accented target words more often than a control group without training. Training was identical in Experiment 2, but during test, canonical German words that overlapped in onset with the accented words from training were presented as target words (e.g., Palme—“palm tree” overlapped in onset with the training word *Palken) rather than accented words. This time, no training effect was observed; recognition of canonical word forms was not affected by having learned the accent. Therefore, accent learning was only visible when the accented test tokens in Experiment 1, which were not included in the test of Experiment 2, possessed sufficient salience based on the objective criterion “accent.” These effects were not modified by the subjective criterion of salience from the training modality. PMID:27375540

  17. Self-Assessment of Individual Differences in Language Switching

    PubMed Central

    Rodriguez-Fornells, Antoni; Krämer, Ulrike M.; Lorenzo-Seva, Urbano; Festman, Julia; Münte, Thomas F.

    2012-01-01

    Language switching is omnipresent in bilingual individuals. In fact, the ability to switch languages (code switching) is a very fast, efficient, and flexible process that seems to be a fundamental aspect of bilingual language processing. In this study, we aimed to characterize psychometrically self-perceived individual differences in language switching and to create a reliable measure of this behavioral pattern by introducing a bilingual switching questionnaire. As a working hypothesis based on the previous literature about code switching, we decomposed language switching into four constructs: (i) L1 switching tendencies (the tendency to switch to L1; L1-switch); (ii) L2 switching tendencies (L2-switch); (iii) contextual switch, which indexes the frequency of switches usually triggered by a particular situation, topic, or environment; and (iv) unintended switch, which measures the lack of intention and awareness of the language switches. A total of 582 Spanish–Catalan bilingual university students were studied. Twelve items were selected (three for each construct). The correlation matrix was factor-analyzed using minimum rank factor analysis followed by oblique direct oblimin rotation. The overall proportion of common variance explained by the four extracted factors was 0.86. Finally, to assess the external validity of the individual differences scored with the new questionnaire, we evaluated the correlations between these measures and several psychometric (language proficiency) and behavioral measures related to cognitive and attentional control. The present study highlights the importance of evaluating individual differences in language switching using self-assessment instruments when studying the interface between cognitive control and bilingualism. PMID:22291668

  18. Selective Attention and Transfer Phenomena in L2 Acquisition: Contingency, Cue Competition, Salience, Interference, Overshadowing, Blocking, and Perceptual Learning

    ERIC Educational Resources Information Center

    Ellis, Nick C.

    2006-01-01

    If first language is rational in the sense that acquisition produces an end-state model of language that is a proper reflection of input and that optimally prepares speakers for comprehension and production, second language is usually not. This paper considers the apparent irrationalities of L2 acquisition, that is the shortcomings where input…

  19. Attention and olfactory consciousness.

    PubMed

    Keller, Andreas

    2011-01-01

    Understanding the relation between attention and consciousness is an important part of our understanding of consciousness. Attention, unlike consciousness, can be systematically manipulated in psychophysical experiments and a law-like relation between attention and consciousness is waiting to be discovered. Most attempts to discover the nature of this relation are focused on a special type of attention: spatial visual attention. In this review I want to introduce another type of attention to the discussion: attention to the olfactory modality. I will first clarify the position of attention to smells in a general taxonomy of attention. I will then review the mechanisms and neuroanatomy of attention and consciousness in the olfactory system before using the newly introduced system to provide evidence that attention is necessary for consciousness. PMID:22203813

  20. Insular dysfunction within the salience network is associated with severity of symptoms and aberrant inter-network connectivity in major depressive disorder

    PubMed Central

    Manoliu, Andrei; Meng, Chun; Brandl, Felix; Doll, Anselm; Tahmasian, Masoud; Scherr, Martin; Schwerthöffer, Dirk; Zimmer, Claus; Förstl, Hans; Bäuml, Josef; Riedl, Valentin; Wohlschläger, Afra M.; Sorg, Christian

    2014-01-01

    Major depressive disorder (MDD) is characterized by altered intrinsic functional connectivity within (intra-iFC) intrinsic connectivity networks (ICNs), such as the Default Mode- (DMN), Salience- (SN) and Central Executive Network (CEN). It has been proposed that aberrant switching between DMN-mediated self-referential and CEN-mediated goal-directed cognitive processes might contribute to MDD, possibly explaining patients' difficulties to disengage the processing of self-focused, often negatively biased thoughts. Recently, it has been shown that the right anterior insula (rAI) within the SN is modulating DMN/CEN interactions. Since structural and functional alterations within the AI have been frequently reported in MDD, we hypothesized that aberrant intra-iFC in the SN's rAI is associated with both aberrant iFC between DMN and CEN (inter-iFC) and severity of symptoms in MDD. Twenty-five patients with MDD and 25 healthy controls were assessed using resting-state fMRI (rs-fMRI) and psychometric examination. High-model-order independent component analysis (ICA) of rs-fMRI data was performed to identify ICNs including DMN, SN, and CEN. Intra-iFC within and inter-iFC between distinct subsystems of the DMN, SN, and CEN were calculated, compared between groups and correlated with the severity of symptoms. Patients with MDD showed (1) decreased intra-iFC within the SN's rAI, (2) decreased inter-iFC between the DMN and CEN, and (3) increased inter-iFC between the SN and DMN. Moreover, decreased intra-iFC in the SN's rAI was associated with severity of symptoms and aberrant DMN/CEN interactions, with the latter losing significance after correction for multiple comparisons. Our results provide evidence for a relationship between aberrant intra-iFC in the salience network's rAI, aberrant DMN/CEN interactions and severity of symptoms, suggesting a link between aberrant salience mapping, abnormal coordination of DMN/CEN based cognitive processes and psychopathology in MDD. PMID

  1. Attentional tunneling and the head-up display

    NASA Technical Reports Server (NTRS)

    Wickens, Christopher D.; Martin-Emerson, Robin; Larish, Inge

    1993-01-01

    Twenty instrument-rated flight students flew simulated landing approaches to a realistic graphics generated airport, using either a head-up display (HUD) of instrument landing systems (ILS) instruments or the same display positioned 8.5 deg. head down. Responses to discrete events appearing either on the ground environment or on the instrument display assessed the pilot's ability to switch attention between these domains. Unexpected events also occurred once (per subject) in each domain. The results revealed that flight path control and attention switching to the instrumnet display was better supported by the HUD, while this advantage disappeared for attention switching to the environment, and for detection of unexpected events. The results are discussed in terms of the attention strategies employed in sampling multiple information sources.

  2. Latching micro optical switch

    DOEpatents

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

    An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.

  3. The scaling of attention networks

    NASA Astrophysics Data System (ADS)

    Wang, Cheng-Jun; Wu, Lingfei

    2016-04-01

    We use clicks as a proxy of collective attention and construct networks to study the temporal dynamics of attention. In particular we collect the browsing records of millions of users on 1000 Web forums in two months. In the constructed networks, nodes are threads and edges represent the switch of users between threads in an hour. The investigated network properties include the number of threads N, the number of users UV, and the number of clicks, PV. We find scaling functions PV ∼ UV θ1, PV ∼N θ3, and UV ∼N θ2, in which the scaling exponents are always greater than 1. This means that (1) the studied networks maintain a self-similar flow structure in time, i.e., large networks are simply the scale-up versions of small networks; and (2) large networks are more "productive", in the sense that an average user would generate more clicks in the larger systems. We propose a revised version of Zipf's law to quantify the time-invariant flow structure of attention networks and relate it to the observed scaling properties. We also demonstrate the applied consequences of our research: forum-classification based on scaling properties.

  4. Resistance switching memory in perovskite oxides

    SciTech Connect

    Yan, Z.B. Liu, J.-M.

    2015-07-15

    The resistance switching behavior has recently attracted great attentions for its application as resistive random access memories (RRAMs) due to a variety of advantages such as simple structure, high-density, high-speed and low-power. As a leading storage media, the transition metal perovskite oxide owns the strong correlation of electrons and the stable crystal structure, which brings out multifunctionality such as ferroelectric, multiferroic, superconductor, and colossal magnetoresistance/electroresistance effect, etc. The existence of rich electronic phases, metal–insulator transition and the nonstoichiometric oxygen in perovskite oxide provides good platforms to insight into the resistive switching mechanisms. In this review, we first introduce the general characteristics of the resistance switching effects, the operation methods and the storage media. Then, the experimental evidences of conductive filaments, the transport and switching mechanisms, and the memory performances and enhancing methods of perovskite oxide based filamentary RRAM cells have been summarized and discussed. Subsequently, the switching mechanisms and the performances of the uniform RRAM cells associating with the carrier trapping/detrapping and the ferroelectric polarization switching have been discussed. Finally, the advices and outlook for further investigating the resistance switching and enhancing the memory performances are given.

  5. Neural Correlates of Attentional Flexibility during Approach and Avoidance Motivation

    PubMed Central

    Calcott, Rebecca D.; Berkman, Elliot T.

    2015-01-01

    Dynamic, momentary approach or avoidance motivational states have downstream effects on eventual goal success and overall well being, but there is still uncertainty about how those states affect the proximal neurocognitive processes (e.g., attention) that mediate the longer-term effects. Attentional flexibility, or the ability to switch between different attentional foci, is one such neurocognitive process that influences outcomes in the long run. The present study examined how approach and avoidance motivational states affect the neural processes involved in attentional flexibility using fMRI with the aim of determining whether flexibility operates via different neural mechanisms under these different states. Attentional flexibility was operationalized as subjects’ ability to switch between global and local stimulus features. In addition to subjects’ motivational state, the task context was manipulated by varying the ratio of global to local trials in a block in light of recent findings about the moderating role of context on motivation-related differences in attentional flexibility. The neural processes involved in attentional flexibility differ under approach versus avoidance states. First, differences in the preparatory activity in key brain regions suggested that subjects’ preparedness to switch was influenced by motivational state (anterior insula) and the interaction between motivation and context (superior temporal gyrus, inferior parietal lobule). Additionally, we observed motivation-related differences the anterior cingulate cortex during switching. These results provide initial evidence that motivation-induced behavioral changes may arise via different mechanisms in approach versus avoidance motivational states. PMID:26000735

  6. Studies of visual attention in physics problem solving

    NASA Astrophysics Data System (ADS)

    Madsen, Adrian M.

    The work described here represents an effort to understand and influence visual attention while solving physics problems containing a diagram. Our visual system is guided by two types of processes -- top-down and bottom-up. The top-down processes are internal and determined by ones prior knowledge and goals. The bottom-up processes are external and determined by features of the visual stimuli such as color, and luminance contrast. When solving physics problems both top-down and bottom-up processes are active, but to varying degrees. The existence of two types of processes opens several interesting questions for physics education. For example, how do bottom-up processes influence problem solvers in physics? Can we leverage these processes to draw attention to relevant diagram areas and improve problem-solving? In this dissertation we discuss three studies that investigate these open questions and rely on eye movements as a primary data source. We assume that eye movements reflect a person's moment-to-moment cognitive processes, providing a window into one's thinking. In our first study, we compared the way correct and incorrect solvers viewed relevant and novice-like elements in a physics problem diagram. We found correct solvers spent more time attending to relevant areas while incorrect solvers spent more time looking at novice-like areas. In our second study, we overlaid these problems with dynamic visual cues to help students' redirect their attention. We found that in some cases these visual cues improved problem-solving performance and influenced visual attention. To determine more precisely how the perceptual salience of diagram elements influenced solvers' attention, we conducted a third study where we manipulated the perceptual salience of the diagram elements via changes in luminance contrast. These changes did not influence participants' answers or visual attention. Instead, similar to our first study, the time spent looking in various areas of the

  7. The salience network causally influences default mode network activity during moral reasoning

    PubMed Central

    Wilson, Stephen M.; D’Esposito, Mark; Kayser, Andrew S.; Grossman, Scott N.; Poorzand, Pardis; Seeley, William W.; Miller, Bruce L.; Rankin, Katherine P.

    2013-01-01

    Large-scale brain networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer’s disease, which targets the default mode network, and behavioural variant frontotemporal dementia, which targets a more anterior salience network. Although the default mode network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, patients with Alzheimer’s disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience network in regulating default mode network activation. Using functional magnetic resonance imaging to characterize network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience network to the default mode network during moral reasoning. First, as previously reported, the default mode network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the default mode network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience network to nodes of the default mode network during moral reasoning. Fourth, this Granger causal influence is diminished in

  8. Heat Switches for ADRs

    NASA Technical Reports Server (NTRS)

    DiPirro, M. J.; Shirron, P. J.

    2014-01-01

    Heat switches are key elements in the cyclic operation of Adiabatic Demagnetization Refrigerators (ADRs). Several of the types of heat switches that have been used for ADRs are described in this paper. Key elements in selection and design of these switches include not only ON/OFF switching ratio, but also method of actuation, size, weight, and structural soundness. Some of the trade-off are detailed in this paper.

  9. Heat switches for ADRs

    NASA Astrophysics Data System (ADS)

    DiPirro, M. J.; Shirron, P. J.

    2014-07-01

    Heat switches are key elements in the cyclic operation of Adiabatic Demagnetization Refrigerators (ADRs). Several of the types of heat switches that have been used for ADRs are described in this paper. Key elements in selection and design of these switches include not only ON/OFF switching ratio, but also method of actuation, size, weight, and structural soundness. Some of the trade-off are detailed in this paper.

  10. Illuminating the dark side of creative expression: assimilation needs and the consequences of creative action following mortality salience.

    PubMed

    Arndt, Jamie; Routledge, Clay; Greenberg, Jeff; Sheldon, Kennon M

    2005-10-01

    Previous research indicates that mortality salience and creative behavior combine to increase feelings of guilt, presumably over the disruption to social connection elicited by the call for innovative expression. The present studies examined whether satiating assimilation motives by highlighting conformity to others reduces this effect (Study 1) and facilitates positive psychological engagement (Study 2). Study 1 used a 2 (conformity vs. neutral feedback)x2 (mortality salience vs. control)x2 (creative task vs. noncreative task) design and had participants complete a self-report measure of guilt. Study 2 used a 2 (mortality salience vs. control)x2 (other goal task vs. self-goal task) design, and after a creativity exercise, had participants complete measures of positive mood, vitality, and creative problem solving. Results indicated attending to assimilation needs reduced the elevated guilt that follows the juxtaposition of mortality salience and creative behavior and also increased a sense of positive engagement. Implications are briefly discussed. PMID:16143665

  11. A Comparative Study of Japanese/English Bilingual Code-Switching in Three Different Domains.

    ERIC Educational Resources Information Center

    Taura, Hideyuki

    This study examined Japanese/English code-switching in three different contexts: a bilingual radio program broadcast in Japan; language of two bilingual siblings; and an adult bilingual dinner party. Particular attention was paid to the situational meanings of code-switching and to politeness issues. Code-switching was examined first at four…

  12. Apollo Ring Optical Switch

    SciTech Connect

    Maestas, J.H.

    1987-03-01

    An optical switch was designed, built, and installed at Sandia National Laboratories in Albuquerque, New Mexico, to facilitate the integration of two Apollo computer networks into a single network. This report presents an overview of the optical switch as well as its layout, switch testing procedure and test data, and installation.

  13. Triggered plasma opening switch

    SciTech Connect

    Mendel, C W

    1988-02-23

    A triggerable opening switch for a very high voltage and current pulse includes a transmission line extending from a source to a load and having an intermediate switch section including a plasma for conducting electrons between transmission line conductors and a magnetic field for breaking the plasma conduction path and magnetically insulating the electrons when it is desired to open the switch.

  14. Triggered plasma opening switch

    DOEpatents

    Mendel, Clifford W.

    1988-01-01

    A triggerable opening switch for a very high voltage and current pulse includes a transmission line extending from a source to a load and having an intermediate switch section including a plasma for conducting electrons between transmission line conductors and a magnetic field for breaking the plasma conduction path and magnetically insulating the electrons when it is desired to open the switch.

  15. Analysis and modeling of resistive switching mechanisms oriented to resistive random-access memory

    NASA Astrophysics Data System (ADS)

    Huang, Da; Wu, Jun-Jie; Tang, Yu-Hua

    2013-03-01

    With the progress of the semiconductor industry, the resistive random-access memory (RAM) has drawn increasing attention. The discovery of the memristor has brought much attention to this study. Research has focused on the resistive switching characteristics of different materials and the analysis of resistive switching mechanisms. We discuss the resistive switching mechanisms of different materials in this paper and analyze the differences of those mechanisms from the view point of circuitry to establish their respective circuit models. Finally, simulations are presented. We give the prospect of using different materials in resistive RAM on account of their resistive switching mechanisms, which are applied to explain their resistive switchings.

  16. Irrelevant stimulus processing in ADHD: catecholamine dynamics and attentional networks

    PubMed Central

    Aboitiz, Francisco; Ossandón, Tomás; Zamorano, Francisco; Palma, Bárbara; Carrasco, Ximena

    2014-01-01

    A cardinal symptom of attention deficit and hyperactivity disorder (ADHD) is a general distractibility where children and adults shift their attentional focus to stimuli that are irrelevant to the ongoing behavior. This has been attributed to a deficit in dopaminergic signaling in cortico-striatal networks that regulate goal-directed behavior. Furthermore, recent imaging evidence points to an impairment of large scale, antagonistic brain networks that normally contribute to attentional engagement and disengagement, such as the task-positive networks and the default mode network (DMN). Related networks are the ventral attentional network (VAN) involved in attentional shifting, and the salience network (SN) related to task expectancy. Here we discuss the tonic–phasic dynamics of catecholaminergic signaling in the brain, and attempt to provide a link between this and the activities of the large-scale cortical networks that regulate behavior. More specifically, we propose that a disbalance of tonic catecholamine levels during task performance produces an emphasis of phasic signaling and increased excitability of the VAN, yielding distractibility symptoms. Likewise, immaturity of the SN may relate to abnormal tonic signaling and an incapacity to build up a proper executive system during task performance. We discuss different lines of evidence including pharmacology, brain imaging and electrophysiology, that are consistent with our proposal. Finally, restoring the pharmacodynamics of catecholaminergic signaling seems crucial to alleviate ADHD symptoms; however, the possibility is open to explore cognitive rehabilitation strategies to top-down modulate network dynamics compensating the pharmacological deficits. PMID:24723897

  17. Perceptual organization and artificial attention for visual landmarks detection.

    PubMed

    Antúnez, Esther; Palomino, Antonio J; Marfil, Rebeca; Bandera, Juan P

    2013-03-01

    In biological vision systems, attention mechanisms are responsible for selecting the relevant information from the sensed field of view, so that the complete scene can be analyzed using a sequence of rapid eye saccades. In recent years, efforts have been made to imitate such attention behavior in artificial vision systems, because it allows optimizing the computational resources as they can be focused on the processing of a set of selected regions. In the framework of mobile robotics navigation, this work proposes an artificial model where attention is deployed at the level of objects (visual landmarks) and where new processes for estimating bottom-up and top-down (target-based) saliency maps are employed. Bottom-up attention is implemented through a hierarchical process, whose final result is the perceptual grouping of the image content. The hierarchical grouping is applied using a Combinatorial Pyramid that represents each level of the hierarchy by a combinatorial map. The process takes into account both image regions (faces in the map) and edges (arcs in the map). Top-down attention searches for previously detected landmarks, enabling their re-detection when the robot presumes that it is revisiting a known location. Landmarks are described by a combinatorial submap; thus, this search is conducted through an error-tolerant submap isomorphism procedure. PMID:23328946

  18. Emotion disrupts neural activity during selective attention in psychopathy.

    PubMed

    Sadeh, Naomi; Spielberg, Jeffrey M; Heller, Wendy; Herrington, John D; Engels, Anna S; Warren, Stacie L; Crocker, Laura D; Sutton, Bradley P; Miller, Gregory A

    2013-03-01

    Dimensions of psychopathy are theorized to be associated with distinct cognitive and emotional abnormalities that may represent unique neurobiological risk factors for the disorder. This hypothesis was investigated by examining whether the psychopathic personality dimensions of fearless-dominance and impulsive-antisociality moderated neural activity and behavioral responses associated with selective attention and emotional processing during an emotion-word Stroop task in 49 adults. As predicted, the dimensions evidenced divergent selective-attention deficits and sensitivity to emotional distraction. Fearless-dominance was associated with disrupted attentional control to positive words, and activation in right superior frontal gyrus mediated the relationship between fearless-dominance and errors to positive words. In contrast, impulsive-antisociality evidenced increased behavioral interference to both positive and negative words and correlated positively with recruitment of regions associated with motivational salience (amygdala, orbitofrontal cortex, insula), emotion regulation (temporal cortex, superior frontal gyrus) and attentional control (dorsal anterior cingulate cortex). Individuals high on both dimensions had increased recruitment of regions related to attentional control (temporal cortex, rostral anterior cingulate cortex), response preparation (pre-/post-central gyri) and motivational value (orbitofrontal cortex) in response to negative words. These findings provide evidence that the psychopathy dimensions represent dual sets of risk factors characterized by divergent dysfunction in cognitive and affective processes. PMID:22210673

  19. Aberrant Salience Is Related to Reduced Reinforcement Learning Signals and Elevated Dopamine Synthesis Capacity in Healthy Adults.

    PubMed

    Boehme, Rebecca; Deserno, Lorenz; Gleich, Tobias; Katthagen, Teresa; Pankow, Anne; Behr, Joachim; Buchert, Ralph; Roiser, Jonathan P; Heinz, Andreas; Schlagenhauf, Florian

    2015-07-15

    The striatum is known to play a key role in reinforcement learning, specifically in the encoding of teaching signals such as reward prediction errors (RPEs). It has been proposed that aberrant salience attribution is associated with impaired coding of RPE and heightened dopamine turnover in the striatum, and might be linked to the development of psychotic symptoms. However, the relationship of aberrant salience attribution, RPE coding, and dopamine synthesis capacity has not been directly investigated. Here we assessed the association between a behavioral measure of aberrant salience attribution, the salience attribution test, to neural correlates of RPEs measured via functional magnetic resonance imaging while healthy participants (n = 58) performed an instrumental learning task. A subset of participants (n = 27) also underwent positron emission tomography with the radiotracer [(18)F]fluoro-l-DOPA to quantify striatal presynaptic dopamine synthesis capacity. Individual variability in aberrant salience measures related negatively to ventral striatal and prefrontal RPE signals and in an exploratory analysis was found to be positively associated with ventral striatal presynaptic dopamine levels. These data provide the first evidence for a specific link between the constructs of aberrant salience attribution, reduced RPE processing, and potentially increased presynaptic dopamine function. PMID:26180188

  20. The interactive effects of mortality salience and political orientation on moral judgments.

    PubMed

    Bassett, Jonathan F; Van Tongeren, Daryl R; Green, Jeffrey D; Sonntag, Michael E; Kilpatrick, Harrison

    2015-06-01

    In two studies, the authors examined how threat induced by reminders of mortality would moderate the effect of political orientation on moral judgments. In Study 1, university students (n = 113) categorized their political orientation, were randomly assigned to complete a fear of death or public speaking scale, and then completed a moral foundations questionnaire. In Study 2, university students (n = 123) rated their political orientations, were randomly assigned to write about their own death or dental pain, and then completed a moral foundations questionnaire. In both studies, mortality salience intensified the moral differences between liberals and conservatives. These findings were primarily the result of the reactions of liberals, who responded to mortality salience with increased ratings of the fairness/cheating virtue in Study 1 and the care/harm virtue in Study 2. PMID:25302551

  1. Visual saliency: a biologically plausible contourlet-like frequency domain approach

    PubMed Central

    Bian, Peng

    2010-01-01

    In this paper we propose a fast frequency domain saliency detection method that is also biologically plausible, referred to as frequency domain divisive normalization (FDN). We show that the initial feature extraction stage, common to all spatial domain approaches, can be simplified to a Fourier transform with a contourlet-like grouping of coefficients, and saliency detection can be achieved in frequency domain. Specifically, we show that divisive normalization, a model of cortical surround inhibition, can be conducted in frequency domain. Since Fourier coefficients are global in space, we extend to this model by conducting piecewise FDN (PFDN) using overlapping local patches to provide better biological plausibility. Not only do FDN and PFDN outperform current state-of-the-art methods in eye fixation prediction, they are also faster. Speed and simplicity are advantages of our frequency domain approach, and its biological plausibility is the main contribution of our paper. PMID:21886671

  2. Predicting Subjective Affective Salience from Cortical Responses to Invisible Object Stimuli.

    PubMed

    Schmack, Katharina; Burk, Julia; Haynes, John-Dylan; Sterzer, Philipp

    2016-08-01

    The affective value of a stimulus substantially influences its potency to gain access to awareness. Here, we sought to elucidate the neural mechanisms underlying such affective salience in a combined behavioral and fMRI experiment. Healthy individuals with varying degrees of spider phobia were presented with pictures of spiders and flowers suppressed from view by continuous flash suppression. Applying multivoxel pattern analysis, we found that the average time that spider stimuli took relative to flowers to gain access to awareness in each participant could be decoded from fMRI signals evoked by suppressed spider versus flower stimuli in occipitotemporal and orbitofrontal cortex. Our results indicate neural signals during unconscious processing of complex visual information in orbitofrontal and ventral visual areas predict access to awareness of this information, suggesting a crucial role for these higher-level cortical regions in mediating affective salience. PMID:26232987

  3. REMOTE CONTROLLED SWITCHING DEVICE

    DOEpatents

    Hobbs, J.C.

    1959-02-01

    An electrical switching device which can be remotely controlled and in which one or more switches may be accurately operated at predetermined times or with predetermined intervening time intervals is described. The switching device consists essentially of a deck, a post projecting from the deck at right angles thereto, cam means mounted for rotation around said posts and a switch connected to said deck and actuated by said cam means. Means is provided for rotating the cam means at a constant speed and the switching apparatus is enclosed in a sealed container with external adjusting means and electrical connection elements.

  4. Salience Network–Based Classification and Prediction of Symptom Severity in Children With Autism

    PubMed Central

    Uddin, Lucina Q.; Supekar, Kaustubh; Lynch, Charles J.; Khouzam, Amirah; Phillips, Jennifer; Feinstein, Carl; Ryali, Srikanth; Menon, Vinod

    2014-01-01

    IMPORTANCE Autism spectrum disorder (ASD) affects 1 in 88 children and is characterized by a complex phenotype, including social, communicative, and sensorimotor deficits. Autism spectrum disorder has been linked with atypical connectivity across multiple brain systems, yet the nature of these differences in young children with the disorder is not well understood. OBJECTIVES To examine connectivity of large-scale brain networks and determine whether specific networks can distinguish children with ASD from typically developing (TD) children and predict symptom severity in children with ASD. DESIGN, SETTING, AND PARTICIPANTS Case-control study performed at Stanford University School of Medicine of 20 children 7 to 12 years old with ASD and 20 age-, sex-, and IQ-matched TD children. MAIN OUTCOMES AND MEASURES Between-group differences in intrinsic functional connectivity of large-scale brain networks, performance of a classifier built to discriminate children with ASD from TD children based on specific brain networks, and correlations between brain networks and core symptoms of ASD. RESULTS We observed stronger functional connectivity within several large-scale brain networks in children with ASD compared with TD children. This hyperconnectivity in ASD encompassed salience, default mode, frontotemporal, motor, and visual networks. This hyperconnectivity result was replicated in an independent cohort obtained from publicly available databases. Using maps of each individual’s salience network, children with ASD could be discriminated from TD children with a classification accuracy of 78%, with 75% sensitivity and 80% specificity. The salience network showed the highest classification accuracy among all networks examined, and the blood oxygen–level dependent signal in this network predicted restricted and repetitive behavior scores. The classifier discriminated ASD from TD in the independent sample with 83% accuracy, 67% sensitivity, and 100% specificity. CONCLUSIONS

  5. Inadequate early social experience increases the incentive salience of reward-related cues in adulthood.

    PubMed

    Lomanowska, Anna M; Lovic, Vedran; Rankine, Michael J; Mooney, Skyler J; Robinson, Terry E; Kraemer, Gary W

    2011-06-20

    The mechanisms by which childhood abuse and/or neglect become risk factors for the development of drug addiction, problem gambling, and other disorders of behavioral inhibition are unknown. The loss of behavioral inhibition is often triggered by reward-related cues that acquire incentive salience. This study examined whether inadequate early-life social experience in rats affects the incentive salience of reward-related cues. Rats were deprived of early-life social experience with the mother and litter through artificial-rearing (AR). A group of AR rats (AR+STM) received additional tactile stimulation that mimicked maternal licking, a critical component of rat maternal care. Control rats were maternally reared (MR). The incentive salience attributed to a food cue was measured in adult rats using a conditioned approach task, where a conditional stimulus (CS; lever) was paired with food delivery, and in a conditional reinforcement task. The dependent measures were approach towards the CS (sign-tracking) versus approach towards the place of food delivery (goal-tracking) and instrumental responding for the CS. AR rats made significantly more sign-tracking responses than MR rats. AR rats also made more instrumental responses when reinforced with the CS. AR+STM rats' responses were intermediate to MR and AR rats. Thus, inadequate early-life social experience enhanced the incentive salience of a reward-related cue in adulthood. Replacement of maternal licking partially reversed this effect. These results highlight a potential link between early-life social adversity and susceptibility to disorders of behavioral inhibition. PMID:21277909

  6. Stress Sensitivity, Aberrant Salience, and Threat Anticipation in Early Psychosis: An Experience Sampling Study.

    PubMed

    Reininghaus, Ulrich; Kempton, Matthew J; Valmaggia, Lucia; Craig, Tom K J; Garety, Philippa; Onyejiaka, Adanna; Gayer-Anderson, Charlotte; So, Suzanne H; Hubbard, Kathryn; Beards, Stephanie; Dazzan, Paola; Pariante, Carmine; Mondelli, Valeria; Fisher, Helen L; Mills, John G; Viechtbauer, Wolfgang; McGuire, Philip; van Os, Jim; Murray, Robin M; Wykes, Til; Myin-Germeys, Inez; Morgan, Craig

    2016-05-01

    While contemporary models of psychosis have proposed a number of putative psychological mechanisms, how these impact on individuals to increase intensity of psychotic experiences in real life, outside the research laboratory, remains unclear. We aimed to investigate whether elevated stress sensitivity, experiences of aberrant novelty and salience, and enhanced anticipation of threat contribute to the development of psychotic experiences in daily life. We used the experience sampling method (ESM) to assess stress, negative affect, aberrant salience, threat anticipation, and psychotic experiences in 51 individuals with first-episode psychosis (FEP), 46 individuals with an at-risk mental state (ARMS) for psychosis, and 53 controls with no personal or family history of psychosis. Linear mixed models were used to account for the multilevel structure of ESM data. In all 3 groups, elevated stress sensitivity, aberrant salience, and enhanced threat anticipation were associated with an increased intensity of psychotic experiences. However, elevated sensitivity to minor stressful events (χ(2)= 6.3,P= 0.044), activities (χ(2)= 6.7,P= 0.036), and areas (χ(2)= 9.4,P= 0.009) and enhanced threat anticipation (χ(2)= 9.3,P= 0.009) were associated with more intense psychotic experiences in FEP individuals than controls. Sensitivity to outsider status (χ(2)= 5.7,P= 0.058) and aberrantly salient experiences (χ(2)= 12.3,P= 0.002) were more strongly associated with psychotic experiences in ARMS individuals than controls. Our findings suggest that stress sensitivity, aberrant salience, and threat anticipation are important psychological processes in the development of psychotic experiences in daily life in the early stages of the disorder. PMID:26834027

  7. Salience Network and Parahippocampal Dopamine Dysfunction in Memory-Impaired Parkinson Disease

    PubMed Central

    Christopher, Leigh; Duff-Canning, Sarah; Koshimori, Yuko; Segura, Barbara; Boileau, Isabelle; Chen, Robert; Lang, Anthony E.; Houle, Sylvain; Rusjan, Pablo; Strafella, Antonio P.

    2016-01-01

    Objective Patients with Parkinson disease (PD) and mild cognitive impairment (MCI) are vulnerable to dementia and frequently experience memory deficits. This could be the result of dopamine dysfunction in corticostriatal networks (salience, central executive networks, and striatum) and/or the medial temporal lobe. Our aim was to investigate whether dopamine dysfunction in these regions contributes to memory impairment in PD. Methods We used positron emission tomography imaging to compare D2 receptor availability in the cortex and striatal (limbic and associative) dopamine neuron integrity in 4 groups: memory-impaired PD (amnestic MCI; n=9), PD with nonamnestic MCI (n=10), PD without MCI (n=11), and healthy controls (n=14). Subjects were administered a full neuropsychological test battery for cognitive performance. Results Memory-impaired patients demonstrated more significant reductions in D2 receptor binding in the salience network (insular cortex and anterior cingulate cortex [ACC] and the right parahippocampal gyrus [PHG]) compared to healthy controls and patients with no MCI. They also presented reductions in the right insula and right ACC compared to nonamnestic MCI patients. D2 levels were correlated with memory performance in the right PHG and left insula of amnestic patients and with executive performance in the bilateral insula and left ACC of all MCI patients. Associative striatal dopamine denervation was significant in all PD patients. Interpretation Dopaminergic differences in the salience network and the medial temporal lobe contribute to memory impairment in PD. Furthermore, these findings indicate the vulnerability of the salience network in PD and its potential role in memory and executive dysfunction. PMID:25448687

  8. Estimating the Relative Sociolinguistic Salience of Segmental Variables in a Dialect Boundary Zone

    PubMed Central

    Llamas, Carmen; Watt, Dominic; MacFarlane, Andrew E.

    2016-01-01

    One way of evaluating the salience of a linguistic feature is by assessing the extent to which listeners associate the feature with a social category such as a particular socioeconomic class, gender, or nationality. Such ‘top–down’ associations will inevitably differ somewhat from listener to listener, as a linguistic feature – the pronunciation of a vowel or consonant, for instance – can evoke multiple social category associations, depending upon the dialect in which the feature is embedded and the context in which it is heard. In a given speech community it is reasonable to expect, as a consequence of the salience of the linguistic form in question, a certain level of intersubjective agreement on social category associations. Two metrics we can use to quantify the salience of a linguistic feature are (a) the speed with which the association is made, and (b) the degree to which members of a speech community appear to share the association. Through the use of a new technique, designed as an adaptation of the Implicit Association Test, this paper examines levels of agreement among 40 informants from the Scottish/English border region with respect to the associations they make between four key phonetic variables and the social categories of ‘Scotland’ and ‘England.’ Our findings reveal that the participants exhibit differential agreement patterns across the set of phonetic variables, and that listeners’ responses vary in line with whether participants are members of the Scottish or the English listener groups. These results demonstrate the importance of community-level agreement with respect to the associations that listeners make between social categories and linguistic forms, and as a means of ranking the forms’ relative salience. PMID:27574511

  9. Stress Sensitivity, Aberrant Salience, and Threat Anticipation in Early Psychosis: An Experience Sampling Study

    PubMed Central

    Reininghaus, Ulrich; Kempton, Matthew J.; Valmaggia, Lucia; Craig, Tom K. J.; Garety, Philippa; Onyejiaka, Adanna; Gayer-Anderson, Charlotte; So, Suzanne H.; Hubbard, Kathryn; Beards, Stephanie; Dazzan, Paola; Pariante, Carmine; Mondelli, Valeria; Fisher, Helen L.; Mills, John G.; Viechtbauer, Wolfgang; McGuire, Philip; van Os, Jim; Murray, Robin M.; Wykes, Til; Myin-Germeys, Inez; Morgan, Craig

    2016-01-01

    While contemporary models of psychosis have proposed a number of putative psychological mechanisms, how these impact on individuals to increase intensity of psychotic experiences in real life, outside the research laboratory, remains unclear. We aimed to investigate whether elevated stress sensitivity, experiences of aberrant novelty and salience, and enhanced anticipation of threat contribute to the development of psychotic experiences in daily life. We used the experience sampling method (ESM) to assess stress, negative affect, aberrant salience, threat anticipation, and psychotic experiences in 51 individuals with first-episode psychosis (FEP), 46 individuals with an at-risk mental state (ARMS) for psychosis, and 53 controls with no personal or family history of psychosis. Linear mixed models were used to account for the multilevel structure of ESM data. In all 3 groups, elevated stress sensitivity, aberrant salience, and enhanced threat anticipation were associated with an increased intensity of psychotic experiences. However, elevated sensitivity to minor stressful events (χ2 = 6.3, P = 0.044), activities (χ2 = 6.7, P = 0.036), and areas (χ2 = 9.4, P = 0.009) and enhanced threat anticipation (χ2 = 9.3, P = 0.009) were associated with more intense psychotic experiences in FEP individuals than controls. Sensitivity to outsider status (χ2 = 5.7, P = 0.058) and aberrantly salient experiences (χ2 = 12.3, P = 0.002) were more strongly associated with psychotic experiences in ARMS individuals than controls. Our findings suggest that stress sensitivity, aberrant salience, and threat anticipation are important psychological processes in the development of psychotic experiences in daily life in the early stages of the disorder. PMID:26834027

  10. Estimating the Relative Sociolinguistic Salience of Segmental Variables in a Dialect Boundary Zone.

    PubMed

    Llamas, Carmen; Watt, Dominic; MacFarlane, Andrew E

    2016-01-01

    One way of evaluating the salience of a linguistic feature is by assessing the extent to which listeners associate the feature with a social category such as a particular socioeconomic class, gender, or nationality. Such 'top-down' associations will inevitably differ somewhat from listener to listener, as a linguistic feature - the pronunciation of a vowel or consonant, for instance - can evoke multiple social category associations, depending upon the dialect in which the feature is embedded and the context in which it is heard. In a given speech community it is reasonable to expect, as a consequence of the salience of the linguistic form in question, a certain level of intersubjective agreement on social category associations. Two metrics we can use to quantify the salience of a linguistic feature are (a) the speed with which the association is made, and (b) the degree to which members of a speech community appear to share the association. Through the use of a new technique, designed as an adaptation of the Implicit Association Test, this paper examines levels of agreement among 40 informants from the Scottish/English border region with respect to the associations they make between four key phonetic variables and the social categories of 'Scotland' and 'England.' Our findings reveal that the participants exhibit differential agreement patterns across the set of phonetic variables, and that listeners' responses vary in line with whether participants are members of the Scottish or the English listener groups. These results demonstrate the importance of community-level agreement with respect to the associations that listeners make between social categories and linguistic forms, and as a means of ranking the forms' relative salience. PMID:27574511

  11. Understanding Attention Deficit Disorders.

    ERIC Educational Resources Information Center

    Villegas, Orlando; And Others

    This booklet provides basic information regarding attention deficit hyperactivity disorders (ADHD), in their separate modalities, with hyperactivity, impulsivity, and inattention. Explanations are offered concerning short attention span, impulsive behavior, hyperactivity, and beginning new activities before completing the previous one. Theories…

  12. Training Visual Attention

    ERIC Educational Resources Information Center

    Mulholland, Thomas B.

    1974-01-01

    The effects of brain waves and alpha rhythms on attentiveness to visual stimuli are discussed, and preliminary research findings and research needs are considered in connection with measuring and training for attention. (LH)

  13. Attention deficit hyperactivity disorder

    MedlinePlus

    Attention deficit hyperactivity disorder (ADHD) is a problem caused by the presence of 1 or more of ... of these behaviors. INATTENTIVE SYMPTOMS Doesn't pay attention to details or makes careless mistakes in schoolwork ...

  14. Hopelessly mortal: The role of mortality salience, immortality and trait self-esteem in personal hope.

    PubMed

    Wisman, Arnaud; Heflick, Nathan A

    2016-08-01

    Do people lose hope when thinking about death? Based on Terror Management Theory, we predicted that thoughts of death (i.e., mortality salience) would reduce personal hope for people low, but not high, in self-esteem, and that this reduction in hope would be ameliorated by promises of immortality. In Studies 1 and 2, mortality salience reduced personal hope for people low in self-esteem, but not for people high in self-esteem. In Study 3, mortality salience reduced hope for people low in self-esteem when they read an argument that there is no afterlife, but not when they read "evidence" supporting life after death. In Study 4, this effect was replicated with an essay affirming scientific medical advances that promise immortality. Together, these findings uniquely demonstrate that thoughts of mortality interact with trait self-esteem to cause changes in personal hope, and that literal immortality beliefs can aid psychological adjustment when thinking about death. Implications for understanding personal hope, trait self-esteem, afterlife beliefs and terror management are discussed. PMID:25920481

  15. Mortality Salience, System Justification, and Candidate Evaluations in the 2012 U.S. Presidential Election.

    PubMed

    Sterling, Joanna; Jost, John T; Shrout, Patrick E

    2016-01-01

    Experiments conducted during the 2004 and 2008 U.S. presidential elections suggested that mortality salience primes increased support for President George W. Bush and Senator John McCain, respectively. Some interpreted these results as reflecting "conservative shift" following exposure to threat, whereas others emphasized preferences for "charismatic" leadership following exposure to death primes. To assess both hypotheses in the context of a new election cycle featuring a liberal incumbent who was considered to be charismatic, we conducted four experiments shortly before the 2012 election involving President Barack Obama and Governor Mitt Romney. Contrary to earlier studies, there was little evidence that mortality salience, either by itself or in interaction with political orientation, affected overall candidate ratings or voting intentions. However, a significant interaction between mortality salience and system justification in some studies indicated a more circumscribed effect. The failure to "replicate" previous results in the context of this election may be attributable to disagreement among participants as to which of the candidates better represented the societal status quo. PMID:26982197

  16. Individual variation in the propensity to attribute incentive salience to a food cue: influence of sex.

    PubMed

    Pitchers, Kyle K; Flagel, Shelly B; O'Donnell, Elizabeth G; Woods, Leah C Solberg; Sarter, Martin; Robinson, Terry E

    2015-02-01

    There is considerable individual variation in the propensity of animals to attribute incentive salience to discrete reward cues, but to date most of this research has been conducted in male rats. The purpose of this study was to determine whether sex influences the propensity to attribute incentive salience to a food cue, using rats from two different outbred strains (Sprague-Dawley [SD] and Heterogeneous Stock [HS]). The motivational value of a food cue was assessed in two ways: (i) by the ability of the cue to elicit approach toward it and (ii) by its ability to act as a conditioned reinforcer. We found that female SD rats acquired Pavlovian conditioned approach behavior slightly faster than males, but no sex difference was detected in HS rats, and neither strain showed a sex difference in asymptotic performance of approach behavior. Moreover, female approach behavior did not differ across estrous cycle. Compared to males, females made more active responses during the test for conditioned reinforcement, although they made more inactive responses as well. We conclude that although there are small sex differences in performance on these tasks, these are probably not due to a notable sex difference in the propensity to attribute incentive salience to a food cue. PMID:25446811

  17. Individual variation in the propensity to attribute incentive salience to a food cue: influence of sex

    PubMed Central

    Pitchers, Kyle K.; Flagel, Shelly B.; O’Donnell, Elizabeth G.; Solberg Woods, Leah C.; Sarter, M.; Robinson, Terry E.

    2014-01-01

    There is considerable individual variation in the propensity of animals to attribute incentive salience to discrete reward cues, but to date most of this research has been conducted in male rats. The purpose of this study was to determine whether sex influences the propensity to attribute incentive salience to a food cue, using rats from two different outbred strains (Sprague-Dawley [SD] and Heterogeneous Stock [HS]). The motivational value of a food cue was assessed in two ways: (i) by the ability of the cue to elicit approach towards it and (ii) by its ability to act as a conditioned reinforcer. We found that female SD rats acquired Pavlovian conditioned approach behavior slightly faster than males, but no sex difference was detected in HS rats, and neither strain showed a sex difference in asymptotic performance of approach behavior. Moreover, female approach behavior did not differ across estrous cycle. Compared to males, females made more active responses during the test for conditioned reinforcement, although they made more inactive responses as well. We conclude that although there are small sex differences in performance on these tasks, these are probably not due to a notable sex difference in the propensity to attribute incentive salience to a food cue. PMID:25446811

  18. The dimensional salience solution to the expectancy-value muddle: an extension.

    PubMed

    Newton, Joshua D; Newton, Fiona J; Ewing, Michael T

    2014-01-01

    The theory of reasoned action (TRA) specifies a set of expectancy-value, belief-based frameworks that underpin attitude (behavioural beliefs × outcome evaluations) and subjective norm (normative beliefs × motivation to comply). Unfortunately, the most common method for analysing these frameworks generates statistically uninterpretable findings, resulting in what has been termed the 'expectancy-value muddle'. Recently, however, a dimensional salience approach was found to resolve this muddle for the belief-based framework underpinning attitude. An online survey of 262 participants was therefore conducted to determine whether the dimensional salience approach could also be applied to the belief-based framework underpinning subjective norm. Results revealed that motivations to comply were greater for salient, as opposed to non-salient, social referents. The belief-based framework underpinning subjective norm was therefore represented by evaluating normative belief ratings for salient social referents. This modified framework was found to predict subjective norm, although predictions were greater when participants were forced to select five salient social referents rather than being free to select any number of social referents. These findings validate the use of the dimensional salience approach for examining the belief-based frameworks underpinning subjective norm. As such, this approach provides a complete solution to addressing the expectancy-value muddle in the TRA. PMID:25088611

  19. Iterative Voting for Inference of Structural Saliency andCharacterization of Subcellular Events

    SciTech Connect

    Parvin, Bahram; Yang, Qing; Han, Ju; Chang, Hang; Rydberg, Bjorn; Barcellos-Hoff, Mary Helen

    2006-05-06

    Saliency is an important perceptual cue that occurs at different levels of resolution. Important attributes of saliency are symmetry, continuity, and closure. Detection of these attributes is often hindered by noise, variation in scale, and incomplete information. This paper introduces the iterative voting method, which uses oriented kernels for inferring saliency as it relates to symmetry. A unique aspect of the technique is the kernel topography, which is refined and reoriented iteratively. The technique can cluster and group nonconvex perceptual circular symmetries along the radial line of an object's shape. It has an excellent noise immunity and is shown to be tolerant to perturbation in scale. The application of this technique to images obtained through various modes of microscopy is demonstrated. Furthermore, as a case example, the method has been applied to quantify kinetics of nuclear foci formation that are formed by phosphorylation of hislone {gamma}H2AX following ionizing radiation. Iterative voting has been implemented in both 2-D and 3-D for multi image analysis.

  20. Mortality Salience, System Justification, and Candidate Evaluations in the 2012 U.S. Presidential Election

    PubMed Central

    Sterling, Joanna; Jost, John T.; Shrout, Patrick E.

    2016-01-01

    Experiments conducted during the 2004 and 2008 U.S. presidential elections suggested that mortality salience primes increased support for President George W. Bush and Senator John McCain, respectively. Some interpreted these results as reflecting “conservative shift” following exposure to threat, whereas others emphasized preferences for “charismatic” leadership following exposure to death primes. To assess both hypotheses in the context of a new election cycle featuring a liberal incumbent who was considered to be charismatic, we conducted four experiments shortly before the 2012 election involving President Barack Obama and Governor Mitt Romney. Contrary to earlier studies, there was little evidence that mortality salience, either by itself or in interaction with political orientation, affected overall candidate ratings or voting intentions. However, a significant interaction between mortality salience and system justification in some studies indicated a more circumscribed effect. The failure to “replicate” previous results in the context of this election may be attributable to disagreement among participants as to which of the candidates better represented the societal status quo. PMID:26982197

  1. The interaction of visual and linguistic saliency during syntactic ambiguity resolution.

    PubMed

    Coco, Moreno I; Keller, Frank

    2015-01-01

    Psycholinguistic research using the visual world paradigm has shown that the processing of sentences is constrained by the visual context in which they occur. Recently, there has been growing interest in the interactions observed when both language and vision provide relevant information during sentence processing. In three visual world experiments on syntactic ambiguity resolution, we investigate how visual and linguistic information influence the interpretation of ambiguous sentences. We hypothesize that (1) visual and linguistic information both constrain which interpretation is pursued by the sentence processor, and (2) the two types of information act upon the interpretation of the sentence at different points during processing. In Experiment 1, we show that visual saliency is utilized to anticipate the upcoming arguments of a verb. In Experiment 2, we operationalize linguistic saliency using intonational breaks and demonstrate that these give prominence to linguistic referents. These results confirm prediction (1). In Experiment 3, we manipulate visual and linguistic saliency together and find that both types of information are used, but at different points in the sentence, to incrementally update its current interpretation. This finding is consistent with prediction (2). Overall, our results suggest an adaptive processing architecture in which different types of information are used when they become available, optimizing different aspects of situated language processing. PMID:25176109

  2. A fast-saliency method for real-time infrared small target detection

    NASA Astrophysics Data System (ADS)

    Qi, Shengxiang; Xu, Guojing; Mou, Zhiying; Huang, Dayu; Zheng, Xueli

    2016-07-01

    Infrared small target detection plays an important role in applications including military reconnaissance, early warning and terminal guidance. In this paper, we present a fast method, called fast-saliency, with very low computational complexity, for real-time small target detection in single image frame under various complex backgrounds. Different from traditional algorithms, the proposed method is inspired by a recent research on visual saliency detection indicating that small salient signals could be well detected by a gradient enhancement operation combined with Gaussian smoothing, which is able to delineate regions of small targets in infrared images. Concisely, there are only four simple steps contained in fast-saliency. In order, they are gradient operation, square computation, Gaussian smoothing and automatic thresholding, representing the four procedures as highpass filtering, target enhancement, noise suppression and target segmentation, respectively. Especially, for the most crucial step, gradient operation, we innovatively propose a 5 × 5 facet kernel operator that holds the key for separating the small targets from backgrounds. To verify the effectiveness of our proposed method, a set of real infrared images covering typical backgrounds with sea, sky and ground clutters are tested in experiments. The results demonstrate that it outperforms the state-of-the-art methods not only in detection accuracy, but also in computation efficiency.

  3. Insula response and connectivity during social and non-social attention in children with autism.

    PubMed

    Odriozola, Paola; Uddin, Lucina Q; Lynch, Charles J; Kochalka, John; Chen, Tianwen; Menon, Vinod

    2016-03-01

    Autism spectrum disorder (ASD) is characterized by reduced attention to salient social stimuli. Here, we use two visual oddball tasks to investigate brain systems engaged during attention to social (face) and non-social (scene) stimuli. We focused on the dorsal and ventral subdivisions of the anterior insula (dAI and vAI, respectively), anatomically distinct regions contributing to a 'salience network' that is known to regulate attention to behaviorally meaningful stimuli. Children with ASD performed comparably to their typically developing (TD) peers, but they engaged the right dAI and vAI differently in response to deviant faces compared with deviant scenes. Multivariate activation patterns in the dAI reliably discriminated between children with ASD and TD children with 85% classification accuracy, and children with ASD activated the vAI more than their TD peers. Children with ASD and their TD peers also differed in dAI connectivity patterns to deviant faces, with stronger within-salience network interactions in the ASD group and stronger cross-network interactions in the TD group. Our findings point to atypical patterns of right anterior insula activation and connectivity in ASD and suggest that multiple functions subserved by the insula, including attention and affective processing of salient social stimuli, are aberrant in children with the disorder. PMID:26454817

  4. Attention Deficit Hyperactivity Disorder

    MedlinePlus

    ... us to find out more about ADHD. Share Attention Deficit Hyperactivity Disorder (Easy-to-Read) Download PDF Download ePub Order ... attention deficit/hyperactivity disorder , or ADHD . What is attention deficit/hyperactivity disorder, or ADHD? ADHD is a common mental disorder ...

  5. Hierarchical nonlinear dynamics of human attention.

    PubMed

    Rabinovich, Mikhail I; Tristan, Irma; Varona, Pablo

    2015-08-01

    Attention is the process of focusing mental resources on a specific cognitive/behavioral task. Such brain dynamics involves different partially overlapping brain functional networks whose interconnections change in time according to the performance stage, and can be stimulus-driven or induced by an intrinsically generated goal. The corresponding activity can be described by different families of spatiotemporal discrete patterns or sequential dynamic modes. Since mental resources are finite, attention modalities compete with each other at all levels of the hierarchy, from perception to decision making and behavior. Cognitive activity is a dynamical process and attention possesses some universal dynamical characteristics. Thus, it is time to apply nonlinear dynamical theory for the description and prediction of hierarchical attentional tasks. Such theory has to include the analyses of attentional control stability, the time cost of attention switching, the finite capacity of informational resources in the brain, and the normal and pathological bifurcations of attention sequential dynamics. In this paper we have integrated today's knowledge, models and results in these directions. PMID:25869439

  6. Multimode resistive switching in single ZnO nanoisland system.

    PubMed

    Qi, Jing; Olmedo, Mario; Zheng, Jian-Guo; Liu, Jianlin

    2013-01-01

    Resistive memory has attracted a great deal of attention as an alternative to contemporary flash memory. Here we demonstrate an interesting phenomenon that multimode resistive switching, i.e. threshold-like, self-rectifying and ordinary bipolar switching, can be observed in one self-assembled single-crystalline ZnO nanoisland with base diameter and height ranging around 30 and 40 nm on Si at different levels of current compliance. Current-voltage characteristics, conductive atomic force microscopy (C-AFM), and piezoresponse force microscopy results show that the threshold-like and self-rectifying types of switching are controlled by the movement of oxygen vacancies in ZnO nanoisland between the C-AFM tip and Si substrate while ordinary bipolar switching is controlled by formation and rupture of conducting nano-filaments. Threshold-like switching leads to a very small switching power density of 1 × 10(3) W/cm(2). PMID:23934276

  7. Attention competition with advertisement

    NASA Astrophysics Data System (ADS)

    Cetin, Uzay; Bingol, Haluk O.

    2014-09-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when the attention capacity of agents is extremely scarce. We have observed that the market share of the advertised item improves if dummy items are introduced to the market while the strength of the advertisement is kept constant.

  8. Attention competition with advertisement.

    PubMed

    Cetin, Uzay; Bingol, Haluk O

    2014-09-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when the attention capacity of agents is extremely scarce. We have observed that the market share of the advertised item improves if dummy items are introduced to the market while the strength of the advertisement is kept constant. PMID:25314476

  9. 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

  10. Effects of attentional training on visual attention to emotional stimuli in archers: A preliminary investigation.

    PubMed

    Chuang, Lan-Ya; Huang, Chung-Ju; Hung, Tsung-Min

    2015-12-01

    Attentional training has been used to modify attentional bias patterns in anxious individuals. This study examined the effect of attentional training on anxious archers' information processing using electrophysiological indices. Eighteen experienced archers with relatively high levels of competitive anxiety were assigned to either a training group or a control group. The training group received a 6-week attentional training protocol that was designed to switch attention away from threats, whereas the control group participated in a placebo training. The results revealed a smaller P1 difference wave for the training group in the posttest compared with pretest, whereas no change in N1 amplitude was found after training. The P1 difference wave finding suggests that more similar visual attentional resources were invested in probes replacing positive cues compared with probes replacing threatening cues after attentional bias training. In particular, archers who accepted training deployed similar attention resources to threatening and positive stimuli but those who accepted sham training avoided attention from threatening stimuli. PMID:26348259

  11. Investigation of methods to search for the boundaries on the image and their use on lung hardware of methods finding saliency map

    NASA Astrophysics Data System (ADS)

    Semenishchev, E. A.; Marchuk, V. I.; Fedosov, V. P.; Stradanchenko, S. G.; Ruslyakov, D. V.

    2015-05-01

    This work aimed to study computationally simple method of saliency map calculation. Research in this field received increasing interest for the use of complex techniques in portable devices. A saliency map allows increasing the speed of many subsequent algorithms and reducing the computational complexity. The proposed method of saliency map detection based on both image and frequency space analysis. Several examples of test image from the Kodak dataset with different detalisation considered in this paper demonstrate the effectiveness of the proposed approach. We present experiments which show that the proposed method providing better results than the framework Salience Toolbox in terms of accuracy and speed.

  12. Neural Dynamics of Attentional Cross-Modality Control

    PubMed Central

    Rabinovich, Mikhail; Tristan, Irma; Varona, Pablo

    2013-01-01

    Attentional networks that integrate many cortical and subcortical elements dynamically control mental processes to focus on specific events and make a decision. The resources of attentional processing are finite. Nevertheless, we often face situations in which it is necessary to simultaneously process several modalities, for example, to switch attention between players in a soccer field. Here we use a global brain mode description to build a model of attentional control dynamics. This model is based on sequential information processing stability conditions that are realized through nonsymmetric inhibition in cortical circuits. In particular, we analyze the dynamics of attentional switching and focus in the case of parallel processing of three interacting mental modalities. Using an excitatory-inhibitory network, we investigate how the bifurcations between different attentional control strategies depend on the stimuli and analyze the relationship between the time of attention focus and the strength of the stimuli. We discuss the interplay between attention and decision-making: in this context, a decision-making process is a controllable bifurcation of the attention strategy. We also suggest the dynamical evaluation of attentional resources in neural sequence processing. PMID:23696890

  13. Cortical Activation Patterns of Bodily Attention triggered by Acupuncture Stimulation

    PubMed Central

    Jung, Won-Mo; Lee, In-Seon; Wallraven, Christian; Ryu, Yeon-Hee; Park, Hi-Joon; Chae, Younbyoung

    2015-01-01

    We investigated commonalities and differences in brain responses to enhanced bodily attention around acupuncture points with and without stimulation. Fourteen participants received acupuncture needles at both PC6 and HT7 acupoints in the left hand. To enhance bodily attention to acupoints, participants responded to the locations of stimulations in a two-alternative forced choice task. Two fMRI scans were taken in a block design: session 1 labeled with manual stimulation (genuine stimulation) and session 2 labeled with electro-acupuncture (pseudo-stimulation). To compare cortical activation patterns, data were analyzed using the Freesurfer software package. Both genuine-and pseudo-stimulation resulted in brain activations in the insula, anterior cingulate cortex, secondary somatosensory cortex, superior parietal cortex, and brain deactivation in the medial prefrontal cortex, posterior cingulate cortex, inferior parietal cortex, and the parahippocampus. Genuine acupuncture stimulation exhibited greater brain activation in the posterior insula, posterior operculum and the caudal part of the anterior cingulate cortex, compared with pseudo-stimulation. We demonstrated that enhanced bodily attention triggered by genuine acupuncture stimulation can activate the salience network and deactivate the default mode network regardless of the type of stimulation. The component of enhanced attention to a certain part of the body is significant in the brain response to acupuncture stimulation. PMID:26211895

  14. Attentional Bias in Snus Users: An Experimental Study

    PubMed Central

    Mentzoni, Rune Aune; Sætrevik, Bjørn; Molde, Helge; Wiium, Nora; Hetland, Jørn; Fagerland, Ida; Nordnes, Linn Tinnesand; Storemark, Sunniva Straume; Fossum, Ingrid Nesdal; Pallesen, Ståle

    2014-01-01

    The use of nicotine in the form of “snus” is substantial and increasing in some geographic areas, in particular among young people. It has previously been suggested that addictions may operate through a mechanism of attentional bias, in which stimuli representative of the dependent substance increase in salience, thus increasing the addictive behavior. However, this hypothesis has not been tested for the case of snus. The current experiment used a modified Stroop task and a dot-probe task to investigate whether 40 snus users show an attentional bias towards snus-relevant stimuli, compared to 40 non-snus users. There were no significant differences between the two groups on reaction times or accuracy on either Stroop or dot-probe task, thus failing to show an attentional bias towards snus-relevant stimuli for snus users. This could imply that other mechanisms may contribute to maintenance of snus use than for other addictions. However, this is the first experimental study investigating attentional bias in snus users, and more research is warranted. PMID:25296339

  15. Effective switching frequency multiplier inverter

    SciTech Connect

    Su, Gui-Jia; Peng, Fang Z.

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  16. Attentional Control in Visual Signal Detection: Effects of Abrupt-Onset and No-Onset Stimuli

    ERIC Educational Resources Information Center

    Sewell, David K.; Smith, Philip L.

    2012-01-01

    The attention literature distinguishes two general mechanisms by which attention can benefit performance: gain (or resource) models and orienting (or switching) models. In gain models, processing efficiency is a function of a spatial distribution of capacity or resources; in orienting models, an attentional spotlight must be aligned with the…

  17. Learning to Look for Language: Development of Joint Attention in Young Deaf Children

    ERIC Educational Resources Information Center

    Lieberman, Amy M.; Hatrak, Marla; Mayberry, Rachel I.

    2014-01-01

    Joint attention between hearing children and their caregivers is typically achieved when the adult provides spoken, auditory linguistic input that relates to the child's current visual focus of attention. Deaf children interacting through sign language must learn to continually switch visual attention between people and objects in order to…

  18. The Role of Attention in the Academic Attainment of Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    May, Tamara; Rinehart, Nicole; Wilding, John; Cornish, Kim

    2013-01-01

    Academic attainment in children with Autism Spectrum Disorder (ASD) is under-studied, with associated factors largely undetermined. Parent-reported attention symptoms, attentional-switching and sustained-attention tasks were examined to determine relationships with mathematics and reading attainment in 124 children aged 7-12 years; sixty-four with…

  19. Thermally actuated thermionic switch

    DOEpatents

    Barrus, D.M.; Shires, C.D.

    1982-09-30

    A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.

  20. Thermally actuated thermionic switch

    DOEpatents

    Barrus, Donald M.; Shires, Charles D.

    1988-01-01

    A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.