Transient emotional events and individual affective traits affect emotion recognition in a perceptual decision-making task.

PubMed

Qiao-Tasserit, Emilie; Garcia Quesada, Maria; Antico, Lia; Bavelier, Daphne; Vuilleumier, Patrik; Pichon, Swann

2017-01-01

Both affective states and personality traits shape how we perceive the social world and interpret emotions. The literature on affective priming has mostly focused on brief influences of emotional stimuli and emotional states on perceptual and cognitive processes. Yet this approach does not fully capture more dynamic processes at the root of emotional states, with such states lingering beyond the duration of the inducing external stimuli. Our goal was to put in perspective three different types of affective states (induced affective states, more sustained mood states and affective traits such as depression and anxiety) and investigate how they may interact and influence emotion perception. Here, we hypothesized that absorption into positive and negative emotional episodes generate sustained affective states that outlast the episode period and bias the interpretation of facial expressions in a perceptual decision-making task. We also investigated how such effects are influenced by more sustained mood states and by individual affect traits (depression and anxiety) and whether they interact. Transient emotional states were induced using movie-clips, after which participants performed a forced-choice emotion classification task with morphed facial expressions ranging from fear to happiness. Using a psychometric approach, we show that negative (vs. neutral) clips increased participants' propensity to classify ambiguous faces as fearful during several minutes. In contrast, positive movies biased classification toward happiness only for those clips perceived as most absorbing. Negative mood, anxiety and depression had a stronger effect than transient states and increased the propensity to classify ambiguous faces as fearful. These results provide the first evidence that absorption and different temporal dimensions of emotions have a significant effect on how we perceive facial expressions.

Transient emotional events and individual affective traits affect emotion recognition in a perceptual decision-making task

PubMed Central

Garcia Quesada, Maria; Antico, Lia; Bavelier, Daphne; Vuilleumier, Patrik; Pichon, Swann

2017-01-01

Both affective states and personality traits shape how we perceive the social world and interpret emotions. The literature on affective priming has mostly focused on brief influences of emotional stimuli and emotional states on perceptual and cognitive processes. Yet this approach does not fully capture more dynamic processes at the root of emotional states, with such states lingering beyond the duration of the inducing external stimuli. Our goal was to put in perspective three different types of affective states (induced affective states, more sustained mood states and affective traits such as depression and anxiety) and investigate how they may interact and influence emotion perception. Here, we hypothesized that absorption into positive and negative emotional episodes generate sustained affective states that outlast the episode period and bias the interpretation of facial expressions in a perceptual decision-making task. We also investigated how such effects are influenced by more sustained mood states and by individual affect traits (depression and anxiety) and whether they interact. Transient emotional states were induced using movie-clips, after which participants performed a forced-choice emotion classification task with morphed facial expressions ranging from fear to happiness. Using a psychometric approach, we show that negative (vs. neutral) clips increased participants’ propensity to classify ambiguous faces as fearful during several minutes. In contrast, positive movies biased classification toward happiness only for those clips perceived as most absorbing. Negative mood, anxiety and depression had a stronger effect than transient states and increased the propensity to classify ambiguous faces as fearful. These results provide the first evidence that absorption and different temporal dimensions of emotions have a significant effect on how we perceive facial expressions. PMID:28151976

Perceptual organization and visual attention.

PubMed

Kimchi, Ruth

2009-01-01

Perceptual organization--the processes structuring visual information into coherent units--and visual attention--the processes by which some visual information in a scene is selected--are crucial for the perception of our visual environment and to visuomotor behavior. Recent research points to important relations between attentional and organizational processes. Several studies demonstrated that perceptual organization constrains attentional selectivity, and other studies suggest that attention can also constrain perceptual organization. In this chapter I focus on two aspects of the relationship between perceptual organization and attention. The first addresses the question of whether or not perceptual organization can take place without attention. I present findings demonstrating that some forms of grouping and figure-ground segmentation can occur without attention, whereas others require controlled attentional processing, depending on the processes involved and the conditions prevailing for each process. These findings challenge the traditional view, which assumes that perceptual organization is a unitary entity that operates preattentively. The second issue addresses the question of whether perceptual organization can affect the automatic deployment of attention. I present findings showing that the mere organization of some elements in the visual field by Gestalt factors into a coherent perceptual unit (an "object"), with no abrupt onset or any other unique transient, can capture attention automatically in a stimulus-driven manner. Taken together, the findings discussed in this chapter demonstrate the multifaceted, interactive relations between perceptual organization and visual attention.

Perceptual Fluency, Auditory Generation, and Metamemory: Analyzing the Perceptual Fluency Hypothesis in the Auditory Modality

ERIC Educational Resources Information Center

Besken, Miri; Mulligan, Neil W.

2014-01-01

Judgments of learning (JOLs) are sometimes influenced by factors that do not impact actual memory performance. One recent proposal is that perceptual fluency during encoding affects metamemory and is a basis of metacognitive illusions. In the present experiments, participants identified aurally presented words that contained inter-spliced silences…

Perceptual load in different regions of the visual scene and its relevance for driving.

PubMed

Marciano, Hadas; Yeshurun, Yaffa

2015-06-01

The aim of this study was to better understand the role played by perceptual load, at both central and peripheral regions of the visual scene, in driving safety. Attention is a crucial factor in driving safety, and previous laboratory studies suggest that perceptual load is an important factor determining the efficiency of attentional selectivity. Yet, the effects of perceptual load on driving were never studied systematically. Using a driving simulator, we orthogonally manipulated the load levels at the road (central load) and its sides (peripheral load), while occasionally introducing critical events at one of these regions. Perceptual load affected driving performance at both regions of the visual scene. Critically, the effect was different for central versus peripheral load: Whereas load levels on the road mainly affected driving speed, load levels on its sides mainly affected the ability to detect critical events initiating from the roadsides. Moreover, higher levels of peripheral load impaired performance but mainly with low levels of central load, replicating findings with simple letter stimuli. Perceptual load has a considerable effect on driving, but the nature of this effect depends on the region of the visual scene at which the load is introduced. Given the observed importance of perceptual load, authors of future studies of driving safety should take it into account. Specifically, these findings suggest that our understanding of factors that may be relevant for driving safety would benefit from studying these factors under different levels of load at different regions of the visual scene. © 2014, Human Factors and Ergonomics Society.

Attentional capture under high perceptual load.

PubMed

Cosman, Joshua D; Vecera, Shaun P

2010-12-01

Attentional capture by abrupt onsets can be modulated by several factors, including the complexity, or perceptual load, of a scene. We have recently demonstrated that observers are less likely to be captured by abruptly appearing, task-irrelevant stimuli when they perform a search that is high, as opposed to low, in perceptual load (Cosman & Vecera, 2009), consistent with perceptual load theory. However, recent results indicate that onset frequency can influence stimulus-driven capture, with infrequent onsets capturing attention more often than did frequent onsets. Importantly, in our previous task, an abrupt onset was present on every trial, and consequently, attentional capture might have been affected by both onset frequency and perceptual load. In the present experiment, we examined whether onset frequency influences attentional capture under conditions of high perceptual load. When onsets were presented frequently, we replicated our earlier results; attentional capture by onsets was modulated under conditions of high perceptual load. Importantly, however, when onsets were presented infrequently, we observed robust capture effects. These results conflict with a strong form of load theory and, instead, suggest that exposure to the elements of a task (e.g., abrupt onsets) combines with high perceptual load to modulate attentional capture by task-irrelevant information.

Fashion advertisements: a comparison of viewers' perceptual and affective responses to illustrated and photographed stimuli.

PubMed

Kimle, P A; Fiore, A M

1992-12-01

The perceptual and affective responses of 44 women to actual illustrated and photographed fashion advertisements during focused interviews were explored. Content analysis methods identified categories of response; frequency of response categories for the two media were compared using Fisher's z tests. Significant differences in perceptual responses included greater visual interest created by the use of color in photographs, greater interest in layout and design features of the illustrations, and interest in characteristics of the models in the photographs. Affective response differences included greater preference for photographic advertisements and the garments in them. Contrary to suggestions from professionals in fashion advertising, no significant differences were found in viewers' perceptions of information about the products in the advertisements or perceptions of meaning and aesthetic response.

Perceptual Discrimination in Static and Dynamic Noise: The Temporal Relation between Perceptual Encoding and Decision Making

ERIC Educational Resources Information Center

Ratcliff, Roger; Smith, Philip L.

2010-01-01

The authors report 9 new experiments and reanalyze 3 published experiments that investigate factors affecting the time course of perceptual processing and its effects on subsequent decision making. Stimuli in letter-discrimination and brightness-discrimination tasks were degraded with static and dynamic noise. The onset and the time course of…

Affective priming with pictures of emotional scenes: the role of perceptual similarity and category relatedness.

PubMed

Avero, Pedro; Calvo, Manuel G

2006-05-01

Prime pictures portraying pleasant or unpleasant scenes were briefly presented (150-ms display; SOAs of 300 or 800 ms), followed by probe pictures either congruent or incongruent in emotional valence. In an evaluative decision task, participants responded whether the probe was emotionally positive or negative. Affective priming was reflected in shorter response latencies for congruent than for incongruent prime-probe pairs. Although this effect was enhanced by perceptual similarity between the prime and the probe, it also occurred for probes that were physically different, and the effect generalized across semantic categories (animals vs. people). It is concluded that affective priming is a genuine phenomenon, in that it occurs as a function of stimulus emotional content, in the absence of both perceptual similarity and semantic category relatedness between the prime and the probe.

Finding an emotional face in a crowd: emotional and perceptual stimulus factors influence visual search efficiency.

PubMed

Lundqvist, Daniel; Bruce, Neil; Öhman, Arne

2015-01-01

In this article, we examine how emotional and perceptual stimulus factors influence visual search efficiency. In an initial task, we run a visual search task, using a large number of target/distractor emotion combinations. In two subsequent tasks, we then assess measures of perceptual (rated and computational distances) and emotional (rated valence, arousal and potency) stimulus properties. In a series of regression analyses, we then explore the degree to which target salience (the size of target/distractor dissimilarities) on these emotional and perceptual measures predict the outcome on search efficiency measures (response times and accuracy) from the visual search task. The results show that both emotional and perceptual stimulus salience contribute to visual search efficiency. The results show that among the emotional measures, salience on arousal measures was more influential than valence salience. The importance of the arousal factor may be a contributing factor to contradictory history of results within this field.

Associations among perceptual anomalies, social anxiety, and paranoia in a college student sample.

PubMed

Tone, Erin B; Goulding, Sandra M; Compton, Michael T

2011-07-30

Recent evidence suggests that normal-range paranoid ideation may be particularly likely to develop in individuals disposed to both social anxiety and perceptual anomalies. This study was designed to test the hypothesis that among college students in an unselected sample, social anxiety and experience of perceptual anomalies would not only each independently predict the experience of self-reported paranoid ideation, but would also interact to predict paranoid patterns of thought. A diverse sample of 644 students completed a large battery of self-report measures, as well as the five-factor Paranoia/Suspiciousness Questionnaire (PSQ). We conducted hierarchical multiple regression analyses predicting scores on each PSQ factor from responses on measures of social anxiety, perceptual aberration, and the interaction between the two constructs. Current general negative affect was covaried in all analyses. We found that both social anxiety and perceptual aberrations, along with negative affect, predicted multiple dimensions of paranoia as measured by the PSQ; the two constructs did not, however, interact significantly to predict any dimensions. Our findings suggest that perceptual aberration and anxiety may contribute to normal-range paranoid ideation in an additive rather than an interactive manner. Copyright © 2011 Elsevier Ltd. All rights reserved.

Attention affects visual perceptual processing near the hand.

PubMed

Cosman, Joshua D; Vecera, Shaun P

2010-09-01

Specialized, bimodal neural systems integrate visual and tactile information in the space near the hand. Here, we show that visuo-tactile representations allow attention to influence early perceptual processing, namely, figure-ground assignment. Regions that were reached toward were more likely than other regions to be assigned as foreground figures, and hand position competed with image-based information to bias figure-ground assignment. Our findings suggest that hand position allows attention to influence visual perceptual processing and that visual processes typically viewed as unimodal can be influenced by bimodal visuo-tactile representations.

Effects of lorazepam on visual perceptual abilities.

PubMed

Pompéia, S; Pradella-Hallinan, M; Manzano, G M; Bueno, O F A

2008-04-01

To evaluate the effects of an acute dose of the benzodiazepine (BZ) lorazepam in young healthy volunteers on five distinguishable visual perception abilities determined by previous factor-analytic studies. This was a double-blind, cross-over design study of acute oral doses of lorazepam (2 mg) and placebo in young healthy volunteers. We focused on a set of paper-and-pencil tests of visual perceptual abilities that load on five correlated but distinguishable factors (Spatial Visualization, Spatial Relations, Perceptual Speed, Closure Speed, and Closure Flexibility). Some other tests (DSST, immediate and delayed recall of prose; measures of subjective mood alterations) were used to control for the classic BZ-induced effects. Lorazepam impaired performance in the DSST and delayed recall of prose, increased subjective sedation and impaired tasks of all abilities except Spatial Visualization and Closure Speed. Only impairment in Perceptual Speed (Identical Pictures task) and delayed recall of prose were not explained by sedation. Acute administration of lorazepam, in a dose that impaired episodic memory, selectively affected different visual perceptual abilities before and after controlling for sedation. Central executive demands and sedation did not account for results, so impairment in the Identical Pictures task may be attributed to lorazepam's visual processing alterations. 2008 John Wiley & Sons, Ltd.

Need for Cognitive Closure Modulates How Perceptual Decisions Are Affected by Task Difficulty and Outcome Relevance.

PubMed

Viola, Vanda; Tosoni, Annalisa; Brizi, Ambra; Salvato, Ilaria; Kruglanski, Arie W; Galati, Gaspare; Mannetti, Lucia

2015-01-01

The aim of this study was to assess the extent to which Need for Cognitive Closure (NCC), an individual-level epistemic motivation, can explain inter-individual variability in the cognitive effort invested on a perceptual decision making task (the random motion task). High levels of NCC are manifested in a preference for clarity, order and structure and a desire for firm and stable knowledge. The study evaluated how NCC moderates the impact of two variables known to increase the amount of cognitive effort invested on a task, namely task ambiguity (i.e., the difficulty of the perceptual discrimination) and outcome relevance (i.e., the monetary gain associated with a correct discrimination). Based on previous work and current design, we assumed that reaction times (RTs) on our motion discrimination task represent a valid index of effort investment. Task ambiguity was associated with increased cognitive effort in participants with low or medium NCC but, interestingly, it did not affect the RTs of participants with high NCC. A different pattern of association was observed for outcome relevance; high outcome relevance increased cognitive effort in participants with moderate or high NCC, but did not affect the performance of low NCC participants. In summary, the performance of individuals with low NCC was affected by task difficulty but not by outcome relevance, whereas individuals with high NCC were influenced by outcome relevance but not by task difficulty; only participants with medium NCC were affected by both task difficulty and outcome relevance. These results suggest that perceptual decision making is influenced by the interaction between context and NCC.

Perceptual learning modifies untrained pursuit eye movements.

PubMed

Szpiro, Sarit F A; Spering, Miriam; Carrasco, Marisa

2014-07-07

Perceptual learning improves detection and discrimination of relevant visual information in mature humans, revealing sensory plasticity. Whether visual perceptual learning affects motor responses is unknown. Here we implemented a protocol that enabled us to address this question. We tested a perceptual response (motion direction estimation, in which observers overestimate motion direction away from a reference) and a motor response (voluntary smooth pursuit eye movements). Perceptual training led to greater overestimation and, remarkably, it modified untrained smooth pursuit. In contrast, pursuit training did not affect overestimation in either pursuit or perception, even though observers in both training groups were exposed to the same stimuli for the same time period. A second experiment revealed that estimation training also improved discrimination, indicating that overestimation may optimize perceptual sensitivity. Hence, active perceptual training is necessary to alter perceptual responses, and an acquired change in perception suffices to modify pursuit, a motor response. © 2014 ARVO.

Perceptual learning modifies untrained pursuit eye movements

PubMed Central

Szpiro, Sarit F. A.; Spering, Miriam; Carrasco, Marisa

2014-01-01

Perceptual learning improves detection and discrimination of relevant visual information in mature humans, revealing sensory plasticity. Whether visual perceptual learning affects motor responses is unknown. Here we implemented a protocol that enabled us to address this question. We tested a perceptual response (motion direction estimation, in which observers overestimate motion direction away from a reference) and a motor response (voluntary smooth pursuit eye movements). Perceptual training led to greater overestimation and, remarkably, it modified untrained smooth pursuit. In contrast, pursuit training did not affect overestimation in either pursuit or perception, even though observers in both training groups were exposed to the same stimuli for the same time period. A second experiment revealed that estimation training also improved discrimination, indicating that overestimation may optimize perceptual sensitivity. Hence, active perceptual training is necessary to alter perceptual responses, and an acquired change in perception suffices to modify pursuit, a motor response. PMID:25002412

Affective state influences perception by affecting decision parameters underlying bias and sensitivity.

PubMed

Lynn, Spencer K; Zhang, Xuan; Barrett, Lisa Feldman

2012-08-01

Studies of the effect of affect on perception often show consistent directional effects of a person's affective state on perception. Unpleasant emotions have been associated with a "locally focused" style of stimulus evaluation, and positive emotions with a "globally focused" style. Typically, however, studies of affect and perception have not been conducted under the conditions of perceptual uncertainty and behavioral risk inherent to perceptual judgments outside the laboratory. We investigated the influence of perceivers' experienced affect (valence and arousal) on the utility of social threat perception by combining signal detection theory and behavioral economics. We compared 3 perceptual decision environments that systematically differed with respect to factors that underlie uncertainty and risk: the base rate of threat, the costs of incorrect identification threat, and the perceptual similarity of threats and nonthreats. We found that no single affective state yielded the best performance on the threat perception task across the 3 environments. Unpleasant valence promoted calibration of response bias to base rate and costs, high arousal promoted calibration of perceptual sensitivity to perceptual similarity, and low arousal was associated with an optimal adjustment of bias to sensitivity. However, the strength of these associations was conditional upon the difficulty of attaining optimal bias and high sensitivity, such that the effect of the perceiver's affective state on perception differed with the cause and/or level of uncertainty and risk.

Where have we gone wrong? Perceptual load does not affect selective attention.

PubMed

Benoni, Hanna; Tsal, Yehoshua

2010-06-18

The theory of perceptual load (Lavie & Tsal, 1994) proposes that with low load in relevant processing left over resources spill over to process irrelevant distractors. Interference could only be prevented under High-Load Conditions where relevant processing exhausts attentional resources. The theory is based primarily on the finding that distractor interference obtained in low load displays, when the target appears alone, is eliminated in high load displays when it is embedded among neutral letters. However, a possible alternative interpretation of this effect is that the distractor is similarly processed in both displays, yet its interference in the large displays is diluted by the presence of the neutral letters. We separated the possible effects of load and dilution by adding dilution displays that were high in dilution and low in perceptual load. In the first experiment these displays contained as many letters as the high load displays, but their neutral letters were clearly distinguished from the target, thereby allowing for a low load processing mode. In the second experiment we presented identical multicolor displays in the Dilution and High-Load Conditions. However, in the former the target color was known in advance (thereby preserving a low load processing mode) whereas in the latter it was not. In both experiments distractor interference was completely eliminated under the Dilution Condition. Thus, it is dilution not perceptual load affecting distractor processing. 2010 Elsevier Ltd. All rights reserved.

Affective State Influences Perception by Affecting Decision Parameters Underlying Bias and Sensitivity

PubMed Central

Lynn, Spencer K.; Zhang, Xuan; Barrett, Lisa Feldman

2012-01-01

Studies of the effect of affect on perception often show consistent directional effects of a person’s affective state on perception. Unpleasant emotions have been associated with a “locally focused” style of stimulus evaluation, and positive emotions with a “globally focused” style. Typically, however, studies of affect and perception have not been conducted under the conditions of perceptual uncertainty and behavioral risk inherent to perceptual judgments outside the laboratory. We investigated the influence of perceivers’ experience affect (valence and arousal) on the utility of social threat perception by combining signal detection theory and behavioral economics. We created three perceptual decision environments that systematically differed with respect to factors that underlie uncertainty and risk: the base rate of threat, the costs of incorrect identification threat, and the perceptual similarity of threats and non-threats. We found that no single affective state yielded the best performance on the threat perception task across the three environments. Unpleasant valence promoted calibration of response bias to base rate and costs, high arousal promoted calibration of perceptual sensitivity to perceptual similarity, and low arousal was associated with an optimal adjustment of bias to sensitivity. However, the strength of these associations was conditional upon the difficulty of attaining optimal bias and high sensitivity, such that the effect of the perceiver’s affective state on perception differed with the cause and/or level of uncertainty and risk. PMID:22251054

The role of selective attention in perceptual and affective priming

NASA Technical Reports Server (NTRS)

Stone, M.; Ladd, S. L.; Gabrieli, J. D.

2000-01-01

Two kinds of perceptual priming (word identification and word fragment completion), as well as preference priming (that may rely on special affective mechanisms) were examined after participants either read or named the colors of words and nonwords at study. Participants named the colors of words more slowly than the colors of nonwords, indicating that lexical processing of the words occurred at study. Nonetheless, priming on all three tests was lower after color naming than after reading, despite evidence of lexical processing during color naming shown by slower responses to words than to nonwords. These results indicate that selective attention to (rather than the mere processing of) letter string identity at study is important for subsequent repetition priming.

Perceptual Grouping Affects Pitch Judgments Across Time and Frequency

PubMed Central

Borchert, Elizabeth M. O.; Micheyl, Christophe; Oxenham, Andrew J.

2010-01-01

Pitch, the perceptual correlate of fundamental frequency (F0), plays an important role in speech, music and animal vocalizations. Changes in F0 over time help define musical melodies and speech prosody, while comparisons of simultaneous F0 are important for musical harmony, and for segregating competing sound sources. This study compared listeners’ ability to detect differences in F0 between pairs of sequential or simultaneous tones that were filtered into separate, non-overlapping spectral regions. The timbre differences induced by filtering led to poor F0 discrimination in the sequential, but not the simultaneous, conditions. Temporal overlap of the two tones was not sufficient to produce good performance; instead performance appeared to depend on the two tones being integrated into the same perceptual object. The results confirm the difficulty of comparing the pitches of sequential sounds with different timbres and suggest that, for simultaneous sounds, pitch differences may be detected through a decrease in perceptual fusion rather than an explicit coding and comparison of the underlying F0s. PMID:21077719

Brief Contemplation as a Factor in the Accuracy of Perceptual Judgments.

ERIC Educational Resources Information Center

Rollman, Steven A.; Gabbard-Alley, Anne

A study investigated the importance of brief contemplation as a factor in the accuracy of judgments about other people, based on their nonverbal appearance. The following questions were addressed: (1) Are observers who are given time to contemplate the significance of nonverbal cues more accurate in their perceptual judgments than observers who…

Movement behaviour within and beyond perceptual ranges in three small mammals: effects of matrix type and body mass.

PubMed

Prevedello, Jayme Augusto; Forero-Medina, Germán; Vieira, Marcus Vinícius

2010-11-01

1. For animal species inhabiting heterogeneous landscapes, the tortuosity of the dispersal path is a key determinant of the success in locating habitat patches. Path tortuosity within and beyond perceptual range must differ, and may be differently affected by intrinsic attributes of individuals and extrinsic environmental factors. Understanding how these factors interact to determine path tortuosity allows more accurate inference of successful movements between habitat patches. 2. We experimentally determined the effects of intrinsic (body mass and species identity) and extrinsic factors (distance to nearest forest fragment and matrix type) on the tortuosity of movements of three forest-dwelling didelphid marsupials, in a fragmented landscape of the Atlantic Forest, Brazil. 3. A total of 202 individuals were captured in forest fragments and released in three unsuitable matrix types (mowed pasture, abandoned pasture and manioc plantation), carrying spool-and-line devices. 4. Twenty-four models were formulated representing a priori hypotheses of major determinants of path tortuosity, grouped in three scenarios (only intrinsic factors, only extrinsic factors and models with combinations of both), and compared using a model selection approach. Models were tested separately for individuals released within the perceptual range of the species, and for individuals released beyond the perceptual range. 5. Matrix type strongly affected path tortuosity, with more obstructed matrix types hampering displacement of animals. Body mass was more important than species identity to determine path tortuosity, with larger animals moving more linearly. Increased distance to the fragment resulted in more tortuous paths, but actually reflects a threshold in perceptual range: linear paths within perceptual range, tortuous paths beyond. 6. The variables tested explained successfully path tortuosity, but only for animals released within the perceptual range. Other factors, such as wind

Perceptual Grouping Enhances Visual Plasticity

PubMed Central

Mastropasqua, Tommaso; Turatto, Massimo

2013-01-01

Visual perceptual learning, a manifestation of neural plasticity, refers to improvements in performance on a visual task achieved by training. Attention is known to play an important role in perceptual learning, given that the observer's discriminative ability improves only for those stimulus feature that are attended. However, the distribution of attention can be severely constrained by perceptual grouping, a process whereby the visual system organizes the initial retinal input into candidate objects. Taken together, these two pieces of evidence suggest the interesting possibility that perceptual grouping might also affect perceptual learning, either directly or via attentional mechanisms. To address this issue, we conducted two experiments. During the training phase, participants attended to the contrast of the task-relevant stimulus (oriented grating), while two similar task-irrelevant stimuli were presented in the adjacent positions. One of the two flanking stimuli was perceptually grouped with the attended stimulus as a consequence of its similar orientation (Experiment 1) or because it was part of the same perceptual object (Experiment 2). A test phase followed the training phase at each location. Compared to the task-irrelevant no-grouping stimulus, orientation discrimination improved at the attended location. Critically, a perceptual learning effect equivalent to the one observed for the attended location also emerged for the task-irrelevant grouping stimulus, indicating that perceptual grouping induced a transfer of learning to the stimulus (or feature) being perceptually grouped with the task-relevant one. Our findings indicate that no voluntary effort to direct attention to the grouping stimulus or feature is necessary to enhance visual plasticity. PMID:23301100

Perceptual grouping enhances visual plasticity.

PubMed

Mastropasqua, Tommaso; Turatto, Massimo

2013-01-01

Visual perceptual learning, a manifestation of neural plasticity, refers to improvements in performance on a visual task achieved by training. Attention is known to play an important role in perceptual learning, given that the observer's discriminative ability improves only for those stimulus feature that are attended. However, the distribution of attention can be severely constrained by perceptual grouping, a process whereby the visual system organizes the initial retinal input into candidate objects. Taken together, these two pieces of evidence suggest the interesting possibility that perceptual grouping might also affect perceptual learning, either directly or via attentional mechanisms. To address this issue, we conducted two experiments. During the training phase, participants attended to the contrast of the task-relevant stimulus (oriented grating), while two similar task-irrelevant stimuli were presented in the adjacent positions. One of the two flanking stimuli was perceptually grouped with the attended stimulus as a consequence of its similar orientation (Experiment 1) or because it was part of the same perceptual object (Experiment 2). A test phase followed the training phase at each location. Compared to the task-irrelevant no-grouping stimulus, orientation discrimination improved at the attended location. Critically, a perceptual learning effect equivalent to the one observed for the attended location also emerged for the task-irrelevant grouping stimulus, indicating that perceptual grouping induced a transfer of learning to the stimulus (or feature) being perceptually grouped with the task-relevant one. Our findings indicate that no voluntary effort to direct attention to the grouping stimulus or feature is necessary to enhance visual plasticity.

Biased and unbiased perceptual decision-making on vocal emotions.

PubMed

Dricu, Mihai; Ceravolo, Leonardo; Grandjean, Didier; Frühholz, Sascha

2017-11-24

Perceptual decision-making on emotions involves gathering sensory information about the affective state of another person and forming a decision on the likelihood of a particular state. These perceptual decisions can be of varying complexity as determined by different contexts. We used functional magnetic resonance imaging and a region of interest approach to investigate the brain activation and functional connectivity behind two forms of perceptual decision-making. More complex unbiased decisions on affective voices recruited an extended bilateral network consisting of the posterior inferior frontal cortex, the orbitofrontal cortex, the amygdala, and voice-sensitive areas in the auditory cortex. Less complex biased decisions on affective voices distinctly recruited the right mid inferior frontal cortex, pointing to a functional distinction in this region following decisional requirements. Furthermore, task-induced neural connectivity revealed stronger connections between these frontal, auditory, and limbic regions during unbiased relative to biased decision-making on affective voices. Together, the data shows that different types of perceptual decision-making on auditory emotions have distinct patterns of activations and functional coupling that follow the decisional strategies and cognitive mechanisms involved during these perceptual decisions.

How mechanisms of perceptual decision-making affect the psychometric function

PubMed Central

Gold, Joshua I.; Ding, Long

2012-01-01

Psychometric functions are often interpreted in the context of Signal Detection Theory, which emphasizes a distinction between sensory processing and non-sensory decision rules in the brain. This framework has helped to relate perceptual sensitivity to the “neurometric” sensitivity of sensory-driven neural activity. However, perceptual sensitivity, as interpreted via Signal Detection Theory, is based on not just how the brain represents relevant sensory information, but also how that information is read out to form the decision variable to which the decision rule is applied. Here we discuss recent advances in our understanding of this readout process and describe its effects on the psychometric function. In particular, we show that particular aspects of the readout process can have specific, identifiable effects on the threshold, slope, upper asymptote, time dependence, and choice dependence of psychometric functions. To illustrate these points, we emphasize studies of perceptual learning that have identified changes in the readout process that can lead to changes in these aspects of the psychometric function. We also discuss methods that have been used to distinguish contributions of the sensory representation versus its readout to psychophysical performance. PMID:22609483

How mechanisms of perceptual decision-making affect the psychometric function.

PubMed

Gold, Joshua I; Ding, Long

2013-04-01

Psychometric functions are often interpreted in the context of Signal Detection Theory, which emphasizes a distinction between sensory processing and non-sensory decision rules in the brain. This framework has helped to relate perceptual sensitivity to the "neurometric" sensitivity of sensory-driven neural activity. However, perceptual sensitivity, as interpreted via Signal Detection Theory, is based on not just how the brain represents relevant sensory information, but also how that information is read out to form the decision variable to which the decision rule is applied. Here we discuss recent advances in our understanding of this readout process and describe its effects on the psychometric function. In particular, we show that particular aspects of the readout process can have specific, identifiable effects on the threshold, slope, upper asymptote, time dependence, and choice dependence of psychometric functions. To illustrate these points, we emphasize studies of perceptual learning that have identified changes in the readout process that can lead to changes in these aspects of the psychometric function. We also discuss methods that have been used to distinguish contributions of the sensory representation versus its readout to psychophysical performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

Studying real-world perceptual expertise

PubMed Central

Shen, Jianhong; Mack, Michael L.; Palmeri, Thomas J.

2014-01-01

Significant insights into visual cognition have come from studying real-world perceptual expertise. Many have previously reviewed empirical findings and theoretical developments from this work. Here we instead provide a brief perspective on approaches, considerations, and challenges to studying real-world perceptual expertise. We discuss factors like choosing to use real-world versus artificial object domains of expertise, selecting a target domain of real-world perceptual expertise, recruiting experts, evaluating their level of expertise, and experimentally testing experts in the lab and online. Throughout our perspective, we highlight expert birding (also called birdwatching) as an example, as it has been used as a target domain for over two decades in the perceptual expertise literature. PMID:25147533

Factors of Predicted Learning Disorders and their Interaction with Attentional and Perceptual Training Procedures.

ERIC Educational Resources Information Center

Friar, John T.

Two factors of predicted learning disorders were investigated: (1) inability to maintain appropriate classroom behavior (BEH), (2) perceptual discrimination deficit (PERC). Three groups of first-graders (BEH, PERC, normal control) were administered measures of impulse control, distractability, auditory discrimination, and visual discrimination.…

Perceptual Judgments of Accented Speech by Listeners from Different First Language Backgrounds

ERIC Educational Resources Information Center

Kang, Okim; Vo, Son Ca Thanh; Moran, Meghan Kerry

2016-01-01

Research in second language speech has often focused on listeners' accent judgment and factors that affect their perception. However, the topic of listeners' application of specific sound categories in their own perceptual judgments has not been widely investigated. The current study explored how listeners from diverse language backgrounds weighed…

Shared mechanisms of perceptual learning and decision making.

PubMed

Law, Chi-Tat; Gold, Joshua I

2010-04-01

Perceptual decisions require the brain to weigh noisy evidence from sensory neurons to form categorical judgments that guide behavior. Here we review behavioral and neurophysiological findings suggesting that at least some forms of perceptual learning do not appear to affect the response properties of neurons that represent the sensory evidence. Instead, improved perceptual performance results from changes in how the sensory evidence is selected and weighed to form the decision. We discuss the implications of this idea for possible sites and mechanisms of training-induced improvements in perceptual processing in the brain. Copyright © 2009 Cognitive Science Society, Inc.

Human perceptual deficits as factors in computer interface test and evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowser, S.E.

1992-06-01

Issues related to testing and evaluating human computer interfaces are usually based on the machine rather than on the human portion of the computer interface. Perceptual characteristics of the expected user are rarely investigated, and interface designers ignore known population perceptual limitations. For these reasons, environmental impacts on the equipment will more likely be defined than will user perceptual characteristics. The investigation of user population characteristics is most often directed toward intellectual abilities and anthropometry. This problem is compounded by the fact that some deficits capabilities tend to be found in higher-than-overall population distribution in some user groups. The testmore » and evaluation community can address the issue from two primary aspects. First, assessing user characteristics should be extended to include tests of perceptual capability. Secondly, interface designs should use multimode information coding.« less

Geometry of the perceptual space

NASA Astrophysics Data System (ADS)

Assadi, Amir H.; Palmer, Stephen; Eghbalnia, Hamid; Carew, John

1999-09-01

The concept of space and geometry varies across the subjects. Following Poincare, we consider the construction of the perceptual space as a continuum equipped with a notion of magnitude. The study of the relationships of objects in the perceptual space gives rise to what we may call perceptual geometry. Computational modeling of objects and investigation of their deeper perceptual geometrical properties (beyond qualitative arguments) require a mathematical representation of the perceptual space. Within the realm of such a mathematical/computational representation, visual perception can be studied as in the well-understood logic-based geometry. This, however, does not mean that one could reduce all problems of visual perception to their geometric counterparts. Rather, visual perception as reported by a human observer, has a subjective factor that could be analytically quantified only through statistical reasoning and in the course of repetitive experiments. Thus, the desire to experimentally verify the statements in perceptual geometry leads to an additional probabilistic structure imposed on the perceptual space, whose amplitudes are measured through intervention by human observers. We propose a model for the perceptual space and the case of perception of textured surfaces as a starting point for object recognition. To rigorously present these ideas and propose computational simulations for testing the theory, we present the model of the perceptual geometry of surfaces through an amplification of theory of Riemannian foliation in differential topology, augmented by statistical learning theory. When we refer to the perceptual geometry of a human observer, the theory takes into account the Bayesian formulation of the prior state of the knowledge of the observer and Hebbian learning. We use a Parallel Distributed Connectionist paradigm for computational modeling and experimental verification of our theory.

Perceptual learning.

PubMed

Seitz, Aaron R

2017-07-10

Perceptual learning refers to how experience can change the way we perceive sights, sounds, smells, tastes, and touch. Examples abound: music training improves our ability to discern tones; experience with food and wines can refine our pallet (and unfortunately more quickly empty our wallet), and with years of training radiologists learn to save lives by discerning subtle details of images that escape the notice of untrained viewers. We often take perceptual learning for granted, but it has a profound impact on how we perceive the world. In this Primer, I will explain how perceptual learning is transformative in guiding our perceptual processes, how research into perceptual learning provides insight into fundamental mechanisms of learning and brain processes, and how knowledge of perceptual learning can be used to develop more effective training approaches for those requiring expert perceptual skills or those in need of perceptual rehabilitation (such as individuals with poor vision). I will make a case that perceptual learning is ubiquitous, scientifically interesting, and has substantial practical utility to us all. Copyright © 2017. Published by Elsevier Ltd.

Perceptual Grouping Affects Pitch Judgments across Time and Frequency

ERIC Educational Resources Information Center

Borchert, Elizabeth M. O.; Micheyl, Christophe; Oxenham, Andrew J.

2011-01-01

Pitch, the perceptual correlate of fundamental frequency (F0), plays an important role in speech, music, and animal vocalizations. Changes in F0 over time help define musical melodies and speech prosody, while comparisons of simultaneous F0 are important for musical harmony, and for segregating competing sound sources. This study compared…

Perceptual structure of adductor spasmodic dysphonia and its acoustic correlates.

PubMed

Cannito, Michael P; Doiuchi, Maki; Murry, Thomas; Woodson, Gayle E

2012-11-01

To examine the perceptual structure of voice attributes in adductor spasmodic dysphonia (ADSD) before and after botulinum toxin treatment and identify acoustic correlates of underlying perceptual factors. Reliability of perceptual judgments is considered in detail. Pre- and posttreatment trial with comparison to healthy controls, using single-blind randomized listener judgments of voice qualities, as well as retrospective comparison with acoustic measurements. Oral readings were recorded from 42 ADSD speakers before and after treatment as well as from their age- and sex-matched controls. Experienced judges listened to speech samples and rated attributes of overall voice quality, breathiness, roughness, and brokenness, using computer-implemented visual analog scaling. Data were adjusted for regression to the mean and submitted to principal components factor analysis. Acoustic waveforms, extracted from the reading samples, were analyzed and measurements correlated with perceptual factor scores. Four reliable perceptual variables of ADSD voice were effectively reduced to two underlying factors that corresponded to hyperadduction, most strongly associated with roughness, and hypoadduction, most strongly associated with breathiness. After treatment, the hyperadduction factor improved, whereas the hypoadduction factor worsened. Statistically significant (P<0.01) correlations were observed between perceived roughness and four acoustic measures, whereas breathiness correlated with aperiodicity and cepstral peak prominence (CPPs). This study supported a two-factor model of ADSD, suggesting perceptual characterization by both hyperadduction and hypoadduction before and after treatment. Responses of the factors to treatment were consistent with previous research. Correlations among perceptual and acoustic variables suggested that multiple acoustic features contributed to the overall impression of roughness. Although CPPs appears to be a partial correlate of perceived

Identity Priming Consistently Affects Perceptual Fluency but Only Affects Metamemory When Primes Are Obvious

ERIC Educational Resources Information Center

Susser, Jonathan A.; Jin, Andy; Mulligan, Neil W.

2016-01-01

Perceptual fluency manipulations influence metamemory judgments, with more fluently perceived information judged as more memorable. However, it is not always clear whether this influence is driven by actual experienced processing fluency or by beliefs about memory. The current study used an identity-priming paradigm--in which words are preceded by…

Competition explains limited attention and perceptual resources: implications for perceptual load and dilution theories.

PubMed

Scalf, Paige E; Torralbo, Ana; Tapia, Evelina; Beck, Diane M

2013-01-01

Both perceptual load theory and dilution theory purport to explain when and why task-irrelevant information, or so-called distractors are processed. Central to both explanations is the notion of limited resources, although the theories differ in the precise way in which those limitations affect distractor processing. We have recently proposed a neurally plausible explanation of limited resources in which neural competition among stimuli hinders their representation in the brain. This view of limited capacity can also explain distractor processing, whereby the competitive interactions and bias imposed to resolve the competition determine the extent to which a distractor is processed. This idea is compatible with aspects of both perceptual load and dilution models of distractor processing, but also serves to highlight their differences. Here we review the evidence in favor of a biased competition view of limited resources and relate these ideas to both classic perceptual load theory and dilution theory.

Attention and perceptual implicit memory: effects of selective versus divided attention and number of visual objects.

PubMed

Mulligan, Neil W

2002-08-01

Extant research presents conflicting results on whether manipulations of attention during encoding affect perceptual priming. Two suggested mediating factors are type of manipulation (selective vs divided) and whether attention is manipulated across multiple objects or within a single object. Words printed in different colors (Experiment 1) or flanked by colored blocks (Experiment 2) were presented at encoding. In the full-attention condition, participants always read the word, in the unattended condition they always identified the color, and in the divided-attention conditions, participants attended to both word identity and color. Perceptual priming was assessed with perceptual identification and explicit memory with recognition. Relative to the full-attention condition, attending to color always reduced priming. Dividing attention between word identity and color, however, only disrupted priming when these attributes were presented as multiple objects (Experiment 2) but not when they were dimensions of a common object (Experiment 1). On the explicit test, manipulations of attention always affected recognition accuracy.

Exogenous and endogenous attention during perceptual learning differentially affect post-training target thresholds

PubMed Central

Mukai, Ikuko; Bahadur, Kandy; Kesavabhotla, Kartik; Ungerleider, Leslie G.

2012-01-01

There is conflicting evidence in the literature regarding the role played by attention in perceptual learning. To further examine this issue, we independently manipulated exogenous and endogenous attention and measured the rate of perceptual learning of oriented Gabor patches presented in different quadrants of the visual field. In this way, we could track learning at attended, divided-attended, and unattended locations. We also measured contrast thresholds of the Gabor patches before and after training. Our results showed that, for both exogenous and endogenous attention, accuracy in performing the orientation discrimination improved to a greater extent at attended than at unattended locations. Importantly, however, only exogenous attention resulted in improved contrast thresholds. These findings suggest that both exogenous and endogenous attention facilitate perceptual learning, but that these two types of attention may be mediated by different neural mechanisms. PMID:21282340

Learning problems, delayed perceptual development, and puberty

NASA Astrophysics Data System (ADS)

Wright, Beverly A.; Zecker, Steven G.; Reid, Miriam D.

2003-04-01

Language-based learning problems affect approximately one person in twelve with no other obvious signs of disorder. Many of these individuals have accompanying deficits in nonlinguistic perception. To determine whether age influences the magnitude of these deficits, thresholds on a set of auditory masking tasks were measured in individuals with learning problems and controls ranging in age from 6 years to adult. Performance improved with increasing age in both groups. However, the thresholds of the individuals with learning problems were most similar to those of controls approximately 2-4 years younger on every task, suggesting that the perceptual development of the affected individuals was delayed by a constant amount. Further, on the subset of conditions on which controls reached adult levels of performance after 10 years of age, the improvement of affected individuals halted at 10 years of age, suggesting that puberty may play a critical role in human perceptual development. Taken together, these data support the idea that some learning problems result from a neuromaturational delay, of unknown breadth, and indicate that neurological changes associated with puberty prevent the complete resolution of delayed perceptual development. [Work supported by NIH/NIDCD.

Perceptual Differences in Attitudes on Quality Circles.

ERIC Educational Resources Information Center

Holcomb, Lynn; Berger, Leonard

1986-01-01

A study was conducted to determine any perceptual differences toward quality circles in a chemical plant. It also tried to determine if any perceptual differences that might be found could be related to attitudes toward the circles themselves or the attitudes toward circle members. Length of service was also a factor. (CT)

Perceptual experience and posttest improvements in perceptual accuracy and consistency.

PubMed

Wagman, Jeffrey B; McBride, Dawn M; Trefzger, Amanda J

2008-08-01

Two experiments investigated the relationship between perceptual experience (during practice) and posttest improvements in perceptual accuracy and consistency. Experiment 1 investigated the potential relationship between how often knowledge of results (KR) is provided during a practice session and posttest improvements in perceptual accuracy. Experiment 2 investigated the potential relationship between how often practice (PR) is provided during a practice session and posttest improvements in perceptual consistency. The results of both experiments are consistent with previous findings that perceptual accuracy improves only when practice includes KR and that perceptual consistency improves regardless of whether practice includes KR. In addition, the results showed that although there is a relationship between how often KR is provided during a practice session and posttest improvements in perceptual accuracy, there is no relationship between how often PR is provided during a practice session and posttest improvements in consistency.

Is Hand Selection Modulated by Cognitive-perceptual Load?

PubMed

Liang, Jiali; Wilkinson, Krista; Sainburg, Robert L

2018-01-15

Previous studies proposed that selecting which hand to use for a reaching task appears to be modulated by a factor described as "task difficulty". However, what features of a task might contribute to greater or lesser "difficulty" in the context of hand selection decisions has yet to be determined. There has been evidence that biomechanical and kinematic factors such as movement smoothness and work can predict patterns of selection across the workspace, suggesting a role of predictive cost analysis in hand-selection. We hypothesize that this type of prediction for hand-selection should recruit substantial cognitive resources and thus should be influenced by cognitive-perceptual loading. We test this hypothesis by assessing the role of cognitive-perceptual loading on hand selection decisions, using a visual search task that presents different levels of difficulty (cognitive-perceptual load), as established in previous studies on overall response time and efficiency of visual search. Although the data are necessarily preliminary due to small sample size, our data suggested an influence of cognitive-perceptual load on hand selection, such that the dominant hand was selected more frequently as cognitive load increased. Interestingly, cognitive-perceptual loading also increased cross-midline reaches with both hands. Because crossing midline is more costly in terms of kinematic and kinetic factors, our findings suggest that cognitive processes are normally engaged to avoid costly actions, and that the choice not-to-cross midline requires cognitive resources. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Sustained Perceptual Deficits from Transient Sensory Deprivation

PubMed Central

Sanes, Dan H.

2015-01-01

Sensory pathways display heightened plasticity during development, yet the perceptual consequences of early experience are generally assessed in adulthood. This approach does not allow one to identify transient perceptual changes that may be linked to the central plasticity observed in juvenile animals. Here, we determined whether a brief period of bilateral auditory deprivation affects sound perception in developing and adult gerbils. Animals were reared with bilateral earplugs, either from postnatal day 11 (P11) to postnatal day 23 (P23) (a manipulation previously found to disrupt gerbil cortical properties), or from P23-P35. Fifteen days after earplug removal and restoration of normal thresholds, animals were tested on their ability to detect the presence of amplitude modulation (AM), a temporal cue that supports vocal communication. Animals reared with earplugs from P11-P23 displayed elevated AM detection thresholds, compared with age-matched controls. In contrast, an identical period of earplug rearing at a later age (P23-P35) did not impair auditory perception. Although the AM thresholds of earplug-reared juveniles improved during a week of repeated testing, a subset of juveniles continued to display a perceptual deficit. Furthermore, although the perceptual deficits induced by transient earplug rearing had resolved for most animals by adulthood, a subset of adults displayed impaired performance. Control experiments indicated that earplugging did not disrupt the integrity of the auditory periphery. Together, our results suggest that P11-P23 encompasses a critical period during which sensory deprivation disrupts central mechanisms that support auditory perceptual skills. SIGNIFICANCE STATEMENT Sensory systems are particularly malleable during development. This heightened degree of plasticity is beneficial because it enables the acquisition of complex skills, such as music or language. However, this plasticity comes with a cost: nervous system development

Perceptual, Categorical, and Affective Processing of Ambiguous Smiling Facial Expressions

ERIC Educational Resources Information Center

Calvo, Manuel G.; Fernandez-Martin, Andres; Nummenmaa, Lauri

2012-01-01

Why is a face with a smile but non-happy eyes likely to be interpreted as happy? We used blended expressions in which a smiling mouth was incongruent with the eyes (e.g., angry eyes), as well as genuine expressions with congruent eyes and mouth (e.g., both happy or angry). Tasks involved detection of a smiling mouth (perceptual), categorization of…

The contribution of perceptual factors and training on varying audiovisual integration capacity.

PubMed

Wilbiks, Jonathan M P; Dyson, Benjamin J

2018-06-01

The suggestion that the capacity of audiovisual integration has an upper limit of 1 was challenged in 4 experiments using perceptual factors and training to enhance the binding of auditory and visual information. Participants were required to note a number of specific visual dot locations that changed in polarity when a critical auditory stimulus was presented, under relatively fast (200-ms stimulus onset asynchrony [SOA]) and slow (700-ms SOA) rates of presentation. In Experiment 1, transient cross-modal congruency between the brightness of polarity change and pitch of the auditory tone was manipulated. In Experiment 2, sustained chunking was enabled on certain trials by connecting varying dot locations with vertices. In Experiment 3, training was employed to determine if capacity would increase through repeated experience with an intermediate presentation rate (450 ms). Estimates of audiovisual integration capacity (K) were larger than 1 during cross-modal congruency at slow presentation rates (Experiment 1), during perceptual chunking at slow and fast presentation rates (Experiment 2), and, during an intermediate presentation rate posttraining (Experiment 3). Finally, Experiment 4 showed a linear increase in K using SOAs ranging from 100 to 600 ms, suggestive of quantitative rather than qualitative changes in the mechanisms in audiovisual integration as a function of presentation rate. The data compromise the suggestion that the capacity of audiovisual integration is limited to 1 and suggest that the ability to bind sounds to sights is contingent on individual and environmental factors. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Internet-based perceptual learning in treating amblyopia.

PubMed

Zhang, Wenqiu; Yang, Xubo; Liao, Meng; Zhang, Ning; Liu, Longqian

2013-01-01

Amblyopia is a common childhood condition, which affects 2%-3% of the population. The efficacy of conventional treatment in amblyopia seems not to be high and recently perceptual learning has been used for treating amblyopia. The aim of this study was to address the efficacy of Internet-based perceptual learning in treating amblyopia. A total of 530 eyes of 341 patients with amblyopia presenting to the outpatient department of West China Hospital of Sichuan University between February 2011 and December 2011 were reviewed. A retrospective cohort study was conducted to compare the efficacy of Internet-based perceptual learning and conventional treatment in amblyopia. The efficacy was evaluated by the change in visual acuity between pretreatment and posttreatment. The change in visual acuity between pretreatment and posttreatment by Internet-based perceptual learning was larger than that by conventional treatment in ametropic and strabismic amblyopia (p<0.05), but smaller than that in anisometropic and other types of amblyopia (p<0.05). The improvement in visual acuity by Internet-based perceptual learning was larger for patients with amblyopia not younger than 7 years (p<0.05). The mean cure time of patients with amblyopia by Internet-based perceptual learning was 3.06 ± 1.42 months, while conventional treatment required 3.52 ± 1.67 months to reach the same improvement (p<0.05). Internet-based perceptual learning can be considered as an alternative to conventional treatment. It is especially suitable for ametropic and strabismic patients with amblyopia who are older than 7 years and can shorten the cure time of amblyopia.

Low level perceptual, not attentional, processes modulate distractor interference in high perceptual load displays: evidence from neglect/extinction.

PubMed

Mevorach, Carmel; Tsal, Yehoshua; Humphreys, Glyn W

2014-01-10

According to perceptual load theory (Lavie, 2005) distractor interference is determined by the availability of attentional resources. If target processing does not exhaust resources (with low perceptual load) distractor processing will take place resulting in interference with a primary task; however, when target processing uses-up attentional capacity (with high perceptual load) interference can be avoided. An alternative account (Tsal and Benoni, 2010a) suggests that perceptual load effects can be based on distractor dilution by the mere presence of additional neutral items in high-load displays so that the effect is not driven by the amount of attention resources required for target processing. Here we tested whether patients with unilateral neglect or extinction would show dilution effects from neutral items in their contralesional (neglected/extinguished) field, even though these items do not impose increased perceptual load on the target and at the same time attract reduced attentional resources compared to stimuli in the ipsilesional field. Thus, such items do not affect the amount of attention resources available for distractor processing. We found that contralesional neutral elements can eliminate distractor interference as strongly as centrally presented ones in neglect/extinction patients, despite contralesional items being less well attended. The data are consistent with an account in terms of perceptual dilution of distracters rather than available resources for distractor processing. We conclude that distractor dilution can underlie the elimination of distractor interference in visual displays.

Probability shapes perceptual precision: A study in orientation estimation.

PubMed

Jabar, Syaheed B; Anderson, Britt

2015-12-01

Probability is known to affect perceptual estimations, but an understanding of mechanisms is lacking. Moving beyond binary classification tasks, we had naive participants report the orientation of briefly viewed gratings where we systematically manipulated contingent probability. Participants rapidly developed faster and more precise estimations for high-probability tilts. The shapes of their error distributions, as indexed by a kurtosis measure, also showed a distortion from Gaussian. This kurtosis metric was robust, capturing probability effects that were graded, contextual, and varying as a function of stimulus orientation. Our data can be understood as a probability-induced reduction in the variability or "shape" of estimation errors, as would be expected if probability affects the perceptual representations. As probability manipulations are an implicit component of many endogenous cuing paradigms, changes at the perceptual level could account for changes in performance that might have traditionally been ascribed to "attention." (c) 2015 APA, all rights reserved).

Concurrent Timbres in Orchestration: a Perceptual Study of Factors Determining "blend"

NASA Astrophysics Data System (ADS)

Sandell, Gregory John

Orchestration often involves selecting instruments for concurrent presentation, as in melodic doubling or chords. One evaluation of the aural outcome of such choices is along the continuum of "blend": whether the instruments fuse into a single composite timbre, segregate into distinct timbral entities, or fall somewhere in between the two extremes. This study investigates, through perceptual experimentation, the acoustical correlates of blend for 15 natural-sounding orchestral instruments presented in concurrently-sounding pairs (e.g. flute-cello, trumpet -oboe, etc.). Ratings of blend showed primary effects for centroid (the location of the midpoint of the spectral energy distribution) and duration of the onset for the tones. Lower average values of both centroid and onset duration for a pair of tones led to increased blends, as did closeness in value for the two factors. Blend decreased (instruments segregated) with higher average values or increased difference in value for the two factors. The musical interval of presentation slightly affected the relative importance of these two mechanisms, with unison intervals determined more by lower average centroid, and minor thirds determined more by closeness in centroid. The contribution of onset in general was slightly more pronounced in the unison conditions than in the minor third condition. Additional factors contributing to blend were correlation of amplitude and centroid envelopes (blend increased as temporal patterns rose and fell in synchrony) and similarity in the overall amount of fundamental frequency perturbation (decreased blend with increasing jitter from both tones). To confirm the importance of centroid as an independent factor determining blend, pairs of tones including instruments with artificially changed centroids were rated for blend. Judgments for several versions of the same instrument pair showed that blend decreased as the altered instrument increased in centroid, corroborating the earlier

Attentional sets influence perceptual load effects, but not dilution effects.

PubMed

Benoni, Hanna; Zivony, Alon; Tsal, Yehoshua

2014-01-01

Perceptual load theory [Lavie, N. (1995). Perceptual load as a necessary condition for selective attention. Journal of Experimental Psychology: Human Perception and Performance, 21, 451-468.; Lavie, N., & Tsal, Y. (1994) Perceptual load as a major determinant of the locus of selection in visual attention. Perception & Psychophysics, 56, 183-197.] proposes that interference from distractors can only be avoided in situations of high perceptual load. This theory has been supported by blocked design manipulations separating low load (when the target appears alone) and high load (when the target is embedded among neutral letters). Tsal and Benoni [(2010a). Diluting the burden of load: Perceptual load effects are simply dilution effects. Journal of Experimental Psychology: Human Perception and Performance, 36, 1645-1656.; Benoni, H., & Tsal, Y. (2010). Where have we gone wrong? Perceptual load does not affect selective attention. Vision Research, 50, 1292-1298.] have recently shown that these manipulations confound perceptual load with "dilution" (the mere presence of additional heterogeneous items in high-load situations). Theeuwes, Kramer, and Belopolsky [(2004). Attentional set interacts with perceptual load in visual search. Psychonomic Bulletin & Review, 11, 697-702.] independently questioned load theory by suggesting that attentional sets might also affect distractor interference. When high load and low load were intermixed, and participants could not prepare for the presentation that followed, both the low-load and high-load trials showed distractor interference. This result may also challenge the dilution account, which proposes a stimulus-driven mechanism. In the current study, we presented subjects with both fixed and mixed blocks, including a mix of dilution trials with low-load trials and with high-load trials. We thus separated the effect of dilution from load and tested the influence of attentional sets on each component. The results revealed that whereas

The role of experience-based perceptual learning in the face inversion effect.

PubMed

Civile, Ciro; Obhi, Sukhvinder S; McLaren, I P L

2018-04-03

Perceptual learning of the type we consider here is a consequence of experience with a class of stimuli. It amounts to an enhanced ability to discriminate between stimuli. We argue that it contributes to the ability to distinguish between faces and recognize individuals, and in particular contributes to the face inversion effect (better recognition performance for upright vs inverted faces). Previously, we have shown that experience with a prototype defined category of checkerboards leads to perceptual learning, that this produces an inversion effect, and that this effect can be disrupted by Anodal tDCS to Fp3 during pre-exposure. If we can demonstrate that the same tDCS manipulation also disrupts the inversion effect for faces, then this will strengthen the claim that perceptual learning contributes to that effect. The important question, then, is whether this tDCS procedure would significantly reduce the inversion effect for faces; stimuli that we have lifelong expertise with and for which perceptual learning has already occurred. Consequently, in the experiment reported here we investigated the effects of anodal tDCS at Fp3 during an old/new recognition task for upright and inverted faces. Our results show that stimulation significantly reduced the face inversion effect compared to controls. The effect was one of reducing recognition performance for upright faces. This result is the first to show that tDCS affects perceptual learning that has already occurred, disrupting individuals' ability to recognize upright faces. It provides further support for our account of perceptual learning and its role as a key factor in face recognition. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of perceptual load on conceptual processing: an extension of Vermeulen's theory.

PubMed

Xie, Jiushu; Wang, Ruiming; Sun, Xun; Chang, Song

2013-10-01

The effect of color and shape load on conceptual processing was studied. Perceptual load effects have been found in visual and auditory conceptual processing, supporting the theory of embodied cognition. However, whether different types of visual concepts, such as color and shape, share the same perceptual load effects is unknown. In the current experiment, 32 participants were administered simultaneous perceptual and conceptual tasks to assess the relation between perceptual load and conceptual processing. Keeping color load in mind obstructed color conceptual processing. Hence, perceptual processing and conceptual load shared the same resources, suggesting embodied cognition. Color conceptual processing was not affected by shape pictures, indicating that different types of properties within vision were separate.

Perceptual load in sport and the heuristic value of the perceptual load paradigm in examining expertise-related perceptual-cognitive adaptations.

PubMed

Furley, Philip; Memmert, Daniel; Schmid, Simone

2013-03-01

In two experiments, we transferred perceptual load theory to the dynamic field of team sports and tested the predictions derived from the theory using a novel task and stimuli. We tested a group of college students (N = 33) and a group of expert team sport players (N = 32) on a general perceptual load task and a complex, soccer-specific perceptual load task in order to extend the understanding of the applicability of perceptual load theory and further investigate whether distractor interference may differ between the groups, as the sport-specific processing task may not exhaust the processing capacity of the expert participants. In both, the general and the specific task, the pattern of results supported perceptual load theory and demonstrates that the predictions of the theory also transfer to more complex, unstructured situations. Further, perceptual load was the only determinant of distractor processing, as we neither found expertise effects in the general perceptual load task nor the sport-specific task. We discuss the heuristic utility of using response-competition paradigms for studying both general and domain-specific perceptual-cognitive adaptations.

Constraints on the Transfer of Perceptual Learning in Accented Speech

PubMed Central

Eisner, Frank; Melinger, Alissa; Weber, Andrea

2013-01-01

The perception of speech sounds can be re-tuned through a mechanism of lexically driven perceptual learning after exposure to instances of atypical speech production. This study asked whether this re-tuning is sensitive to the position of the atypical sound within the word. We investigated perceptual learning using English voiced stop consonants, which are commonly devoiced in word-final position by Dutch learners of English. After exposure to a Dutch learner’s productions of devoiced stops in word-final position (but not in any other positions), British English (BE) listeners showed evidence of perceptual learning in a subsequent cross-modal priming task, where auditory primes with devoiced final stops (e.g., “seed”, pronounced [si:th]), facilitated recognition of visual targets with voiced final stops (e.g., SEED). In Experiment 1, this learning effect generalized to test pairs where the critical contrast was in word-initial position, e.g., auditory primes such as “town” facilitated recognition of visual targets like DOWN. Control listeners, who had not heard any stops by the speaker during exposure, showed no learning effects. The generalization to word-initial position did not occur when participants had also heard correctly voiced, word-initial stops during exposure (Experiment 2), and when the speaker was a native BE speaker who mimicked the word-final devoicing (Experiment 3). The readiness of the perceptual system to generalize a previously learned adjustment to other positions within the word thus appears to be modulated by distributional properties of the speech input, as well as by the perceived sociophonetic characteristics of the speaker. The results suggest that the transfer of pre-lexical perceptual adjustments that occur through lexically driven learning can be affected by a combination of acoustic, phonological, and sociophonetic factors. PMID:23554598

Conceptual and methodological concerns in the theory of perceptual load.

PubMed

Benoni, Hanna; Tsal, Yehoshua

2013-01-01

The present paper provides a short critical review of the theory of perceptual load. It closely examines the basic tenets and assumptions of the theory and identifies major conceptual and methodological problems that have been largely ignored in the literature. The discussion focuses on problems in the definition of the concept of perceptual load, on the circularity in the characterization and manipulation of perceptual load and the confusion between the concept of perceptual load and its operationalization. The paper also selectively reviews evidence supporting the theory as well as inconsistent evidence which proposed alternative dominant factors influencing the efficacy of attentional selection.

Linking Cognitive and Visual Perceptual Decline in Healthy Aging: The Information Degradation Hypothesis

PubMed Central

Monge, Zachary A.; Madden, David J.

2016-01-01

Several hypotheses attempt to explain the relation between cognitive and perceptual decline in aging (e.g., common-cause, sensory deprivation, cognitive load on perception, information degradation). Unfortunately, the majority of past studies examining this association have used correlational analyses, not allowing for these hypotheses to be tested sufficiently. This correlational issue is especially relevant for the information degradation hypothesis, which states that degraded perceptual signal inputs, resulting from either age-related neurobiological processes (e.g., retinal degeneration) or experimental manipulations (e.g., reduced visual contrast), lead to errors in perceptual processing, which in turn may affect non-perceptual, higher-order cognitive processes. Even though the majority of studies examining the relation between age-related cognitive and perceptual decline have been correlational, we reviewed several studies demonstrating that visual manipulations affect both younger and older adults’ cognitive performance, supporting the information degradation hypothesis and contradicting implications of other hypotheses (e.g., common-cause, sensory deprivation, cognitive load on perception). The reviewed evidence indicates the necessity to further examine the information degradation hypothesis in order to identify mechanisms underlying age-related cognitive decline. PMID:27484869

General recognition theory with individual differences: a new method for examining perceptual and decisional interactions with an application to face perception.

PubMed

Soto, Fabian A; Vucovich, Lauren; Musgrave, Robert; Ashby, F Gregory

2015-02-01

A common question in perceptual science is to what extent different stimulus dimensions are processed independently. General recognition theory (GRT) offers a formal framework via which different notions of independence can be defined and tested rigorously, while also dissociating perceptual from decisional factors. This article presents a new GRT model that overcomes several shortcomings with previous approaches, including a clearer separation between perceptual and decisional processes and a more complete description of such processes. The model assumes that different individuals share similar perceptual representations, but vary in their attention to dimensions and in the decisional strategies they use. We apply the model to the analysis of interactions between identity and emotional expression during face recognition. The results of previous research aimed at this problem have been disparate. Participants identified four faces, which resulted from the combination of two identities and two expressions. An analysis using the new GRT model showed a complex pattern of dimensional interactions. The perception of emotional expression was not affected by changes in identity, but the perception of identity was affected by changes in emotional expression. There were violations of decisional separability of expression from identity and of identity from expression, with the former being more consistent across participants than the latter. One explanation for the disparate results in the literature is that decisional strategies may have varied across studies and influenced the results of tests of perceptual interactions, as previous studies lacked the ability to dissociate between perceptual and decisional interactions.

Aging does not affect brain patterns of repetition effects associated with perceptual priming of novel objects.

PubMed

Soldan, Anja; Gazes, Yunglin; Hilton, H John; Stern, Yaakov

2008-10-01

This study examined how aging affects the spatial patterns of repetition effects associated with perceptual priming of unfamiliar visual objects. Healthy young (n = 14) and elderly adults (n = 13) viewed four repetitions of structurally possible and impossible figures while being scanned with blood oxygenation level-dependent functional magnetic resonance imaging. Although explicit recognition memory for the figures was reduced in the elder subjects, repetition priming did not differ across the two age groups. Using multivariate linear modeling, we found that the spatial networks of regions that demonstrated repetition-related increases and decreases in activity were identical in both age groups, although there was a trend for smaller magnitude repetition effects in these networks in the elder adults for objects that had been repeated thrice. Furthermore, repetition-related reductions in activity in the left inferior frontal cortex for possible objects correlated with repetition-related facilitation in reaction time across both young and elder subjects. Repetition-related increases of an initially negative response were observed for both object types in both age groups in parts of the default network, suggesting that less attention was required for processing repeated stimuli. These findings extend prior studies using verbal and semantic picture priming tasks and support the view that perceptual repetition priming remains intact in later adulthood because the same spatial networks of regions continue to show repetition-related neural plasticity across the adult life span.

Sourcebook of Temporal Factors Affecting Information Transfer from Visual Displays

DTIC Science & Technology

1981-06-01

moving object and take appropriate action? Obviously, these behaviors are affected not only by motion perception but by memory and motor control as...Perf., 1975, 1, 383394. Layton, B. Perceptual Noise and Aging. Psych. Bull., 1975, 82, 875- 883. LeGrand, Y. Light, colour and vision. Ch. 13, time...ligkeit intermittierender lichtreize von der flimmerfreque (Brucke-effekt,,, brightness enchancement ): Unt!rsuchungen bei verschiedener leuchtdichte

Temporal characteristics of the influence of punishment on perceptual decision making in the human brain.

PubMed

Blank, Helen; Biele, Guido; Heekeren, Hauke R; Philiastides, Marios G

2013-02-27

Perceptual decision making is the process by which information from sensory systems is combined and used to influence our behavior. In addition to the sensory input, this process can be affected by other factors, such as reward and punishment for correct and incorrect responses. To investigate the temporal dynamics of how monetary punishment influences perceptual decision making in humans, we collected electroencephalography (EEG) data during a perceptual categorization task whereby the punishment level for incorrect responses was parametrically manipulated across blocks of trials. Behaviorally, we observed improved accuracy for high relative to low punishment levels. Using multivariate linear discriminant analysis of the EEG, we identified multiple punishment-induced discriminating components with spatially distinct scalp topographies. Compared with components related to sensory evidence, components discriminating punishment levels appeared later in the trial, suggesting that punishment affects primarily late postsensory, decision-related processing. Crucially, the amplitude of these punishment components across participants was predictive of the size of the behavioral improvements induced by punishment. Finally, trial-by-trial changes in prestimulus oscillatory activity in the alpha and gamma bands were good predictors of the amplitude of these components. We discuss these findings in the context of increased motivation/attention, resulting from increases in punishment, which in turn yields improved decision-related processing.

Conceptual and methodological concerns in the theory of perceptual load

PubMed Central

Benoni, Hanna; Tsal, Yehoshua

2013-01-01

The present paper provides a short critical review of the theory of perceptual load. It closely examines the basic tenets and assumptions of the theory and identifies major conceptual and methodological problems that have been largely ignored in the literature. The discussion focuses on problems in the definition of the concept of perceptual load, on the circularity in the characterization and manipulation of perceptual load and the confusion between the concept of perceptual load and its operationalization. The paper also selectively reviews evidence supporting the theory as well as inconsistent evidence which proposed alternative dominant factors influencing the efficacy of attentional selection. PMID:23964262

Alcohol affects neuronal substrates of response inhibition but not of perceptual processing of stimuli signalling a stop response.

PubMed

Nikolaou, Kyriaki; Critchley, Hugo; Duka, Theodora

2013-01-01

Alcohol impairs inhibitory control, including the ability to terminate an initiated action. While there is increasing knowledge about neural mechanisms involved in response inhibition, the level at which alcohol impairs such mechanisms remains poorly understood. Thirty-nine healthy social drinkers received either 0.4 g/kg or 0.8 g/kg of alcohol, or placebo, and performed two variants of a Visual Stop-signal task during acquisition of functional magnetic resonance imaging (fMRI) data. The two task variants differed only in their instructions: in the classic variant (VSST), participants inhibited their response to a "Go-stimulus" when it was followed by a "Stop-stimulus". In the control variant (VSST_C), participants responded to the "Go-stimulus" even if it was followed by a "Stop-stimulus". Comparison of successful Stop-trials (Sstop)>Go, and unsuccessful Stop-trials (Ustop)>Sstop between the three beverage groups enabled the identification of alcohol effects on functional neural circuits supporting inhibitory behaviour and error processing. Alcohol impaired inhibitory control as measured by the Stop-signal reaction time, but did not affect other aspects of VSST performance, nor performance on the VSST_C. The low alcohol dose evoked changes in neural activity within prefrontal, temporal, occipital and motor cortices. The high alcohol dose evoked changes in activity in areas affected by the low dose but importantly induced changes in activity within subcortical centres including the globus pallidus and thalamus. Alcohol did not affect neural correlates of perceptual processing of infrequent cues, as revealed by conjunction analyses of VSST and VSST_C tasks. Alcohol ingestion compromises the inhibitory control of action by modulating cortical regions supporting attentional, sensorimotor and action-planning processes. At higher doses the impact of alcohol also extends to affect subcortical nodes of fronto-basal ganglia- thalamo-cortical motor circuits. In contrast

Perceptual and Social Attributes Underlining Age-Related Preferences for Faces

PubMed Central

Kiiski, Hanni S. M.; Cullen, Brendan; Clavin, Sarah L.; Newell, Fiona N.

2016-01-01

Although aesthetic preferences are known to be important in person perception and can play a significant role in everyday social decisions, the effect of the age of the observer on aesthetic preferences for faces of different ages has not yet been fully investigated. In the present study we investigated whether aesthetic preferences change with aging, with an age-related bias in favoring faces from one’s own age group. In addition, we examined the role of age on both the perceptual qualities and the social attributes of faces that may influence these aesthetic judgements. Both younger and older adult observers provided ratings to images of younger, middle-aged and older unfamiliar faces. As well as attractiveness, the rating dimensions included other perceptual (distinctiveness, familiarity) and social (competence, trustworthiness and dominance) factors. The results suggested a consistent aesthetic preference for youthful faces across all ages of the observers but, surprisingly, no evidence for an age-related bias in attractiveness ratings. Older adults tended to provide higher ratings of attractiveness, competence and trustworthiness to the unfamiliar faces, consistent with the positivity effect previously reported. We also tested whether perceptual factors such as face familiarity or distinctiveness affected aesthetic ratings. Only ratings of familiarity, but not distinctiveness, were positively associated with the attractiveness of the faces. Moreover, ratings of familiarity decreased with increasing age of the face. With regard to the social characteristics of the faces, we found that the age of the face negatively correlated with ratings of trustworthiness provided by all observers, but with the competence ratings of older observers only. Interestingly, older adults provided higher ratings of perceived competence and trustworthiness to younger than older faces. However, our results also suggest that higher attractiveness ratings, together with older aged

The effect of perceptual load on tactile spatial attention: Evidence from event-related potentials.

PubMed

Gherri, Elena; Berreby, Fiona

2017-10-15

To investigate whether tactile spatial attention is modulated by perceptual load, behavioural and electrophysiological measures were recorded during two spatial cuing tasks in which the difficulty of the target/non-target discrimination was varied (High and Low load tasks). Moreover, to study whether attentional modulations by load are sensitive to the availability of visual information, the High and Low load tasks were carried out under both illuminated and darkness conditions. ERPs to cued and uncued non-targets were compared as a function of task (High vs. Low load) and illumination condition (Light vs. Darkness). Results revealed that the locus of tactile spatial attention was determined by a complex interaction between perceptual load and illumination conditions during sensory-specific stages of processing. In the Darkness, earlier effects of attention were present in the High load than in the Low load task, while no difference between tasks emerged in the Light. By contrast, increased load was associated with stronger attention effects during later post-perceptual processing stages regardless of illumination conditions. These findings demonstrate that ERP correlates of tactile spatial attention are strongly affected by the perceptual load of the target/non-target discrimination. However, differences between illumination conditions show that the impact of load on tactile attention depends on the presence of visual information. Perceptual load is one of the many factors that contribute to determine the effects of spatial selectivity in touch. Copyright © 2017 Elsevier B.V. All rights reserved.

Multivoxel neurofeedback selectively modulates confidence without changing perceptual performance

PubMed Central

Cortese, Aurelio; Amano, Kaoru; Koizumi, Ai; Kawato, Mitsuo; Lau, Hakwan

2016-01-01

A central controversy in metacognition studies concerns whether subjective confidence directly reflects the reliability of perceptual or cognitive processes, as suggested by normative models based on the assumption that neural computations are generally optimal. This view enjoys popularity in the computational and animal literatures, but it has also been suggested that confidence may depend on a late-stage estimation dissociable from perceptual processes. Yet, at least in humans, experimental tools have lacked the power to resolve these issues convincingly. Here, we overcome this difficulty by using the recently developed method of decoded neurofeedback (DecNef) to systematically manipulate multivoxel correlates of confidence in a frontoparietal network. Here we report that bi-directional changes in confidence do not affect perceptual accuracy. Further psychophysical analyses rule out accounts based on simple shifts in reporting strategy. Our results provide clear neuroscientific evidence for the systematic dissociation between confidence and perceptual performance, and thereby challenge current theoretical thinking. PMID:27976739

The Influence of Emotional State and Pictorial Cues on Perceptual Judgments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kimberly R. Raddatz; Abigail Werth; Tuan Q. Tran

2007-10-01

Perspective displays (e.g., CDTI) are commonly used as decision aids in environments characterized by periods of high emotional arousal (e.g., terrain enhanced primary flight displays). However, little attention has been devoted to understanding how emotional state, independently or in conjunction with other perceptual factors (e.g., pictorial depth cues), can impact perceptual judgments. Preliminary research suggests that induced emotional state (positive or negative) adversely impacts size comparisons in perspective displays (Tran & Raddatz, 2006). This study further investigated how size comparisons are affected by emotional state and pictorial depth cues while attenuating the limitations of the Tran & Raddatz (2006) study.more » Results confirmed that observers do make slower judgments under induced emotional state. However, observers under negative emotional state showed higher sensitivity (d’) and required more evidence to respond that a size difference exists (response bias) than observers under positive emotional state. Implications for display design and human performance are discussed.« less

Bayesian Face Recognition and Perceptual Narrowing in Face-Space

PubMed Central

Balas, Benjamin

2012-01-01

During the first year of life, infants’ face recognition abilities are subject to “perceptual narrowing,” the end result of which is that observers lose the ability to distinguish previously discriminable faces (e.g. other-race faces) from one another. Perceptual narrowing has been reported for faces of different species and different races, in developing humans and primates. Though the phenomenon is highly robust and replicable, there have been few efforts to model the emergence of perceptual narrowing as a function of the accumulation of experience with faces during infancy. The goal of the current study is to examine how perceptual narrowing might manifest as statistical estimation in “face space,” a geometric framework for describing face recognition that has been successfully applied to adult face perception. Here, I use a computer vision algorithm for Bayesian face recognition to study how the acquisition of experience in face space and the presence of race categories affect performance for own and other-race faces. Perceptual narrowing follows from the establishment of distinct race categories, suggesting that the acquisition of category boundaries for race is a key computational mechanism in developing face expertise. PMID:22709406

Top-down (Prior Knowledge) and Bottom-up (Perceptual Modality) Influences on Spontaneous Interpersonal Synchronization.

PubMed

Gipson, Christina L; Gorman, Jamie C; Hessler, Eric E

2016-04-01

Coordination with others is such a fundamental part of human activity that it can happen unintentionally. This unintentional coordination can manifest as synchronization and is observed in physical and human systems alike. We investigated the role of top-down influences (prior knowledge of the perceptual modality their partner is using) and bottom-up factors (perceptual modality combination) on spontaneous interpersonal synchronization. We examine this phenomena with respect to two different theoretical perspectives that differently emphasize top-down and bottom-up factors in interpersonal synchronization: joint-action/shared cognition theories and ecological-interactive theories. In an empirical study twelve dyads performed a finger oscillation task while attending to each other's movements through either visual, auditory, or visual and auditory perceptual modalities. Half of the participants were given prior knowledge of their partner's perceptual capabilities for coordinating across these different perceptual modality combinations. We found that the effect of top-down influence depends on the perceptual modality combination between two individuals. When people used the same perceptual modalities, top-down influence resulted in less synchronization and when people used different perceptual modalities, top-down influence resulted in more synchronization. Furthermore, persistence in the change in behavior as a result of having perceptual information about each other ('social memory') was stronger when this top-down influence was present.

Load theory behind the wheel; perceptual and cognitive load effects.

PubMed

Murphy, Gillian; Greene, Ciara M

2017-09-01

Perceptual Load Theory has been proposed as a resolution to the longstanding early versus late selection debate in cognitive psychology. There is much evidence in support of Load Theory but very few applied studies, despite the potential for the model to shed light on everyday attention and distraction. Using a driving simulator, the effect of perceptual and cognitive load on drivers' visual search was assessed. The findings were largely in line with Load Theory, with reduced distractor processing under high perceptual load, but increased distractor processing under high cognitive load. The effect of load on driving behaviour was also analysed, with significant differences in driving behaviour under perceptual and cognitive load. In addition, the effect of perceptual load on drivers' levels of awareness was investigated. High perceptual load significantly increased inattentional blindness and deafness, for stimuli that were both relevant and irrelevant to driving. High perceptual load also increased RTs to hazards. The current study helps to advance Load Theory by illustrating its usefulness outside of traditional paradigms. There are also applied implications for driver safety and roadway design, as the current study suggests that perceptual and cognitive load are important factors in driver attention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Reliability in perceptual analysis of voice quality.

PubMed

Bele, Irene Velsvik

2005-12-01

This study focuses on speaking voice quality in male teachers (n = 35) and male actors (n = 36), who represent untrained and trained voice users, because we wanted to investigate normal and supranormal voices. In this study, both substantial and methodologic aspects were considered. It includes a method for perceptual voice evaluation, and a basic issue was rater reliability. A listening group of 10 listeners, 7 experienced speech-language therapists, and 3 speech-language therapist students evaluated the voices by 15 vocal characteristics using VA scales. Two sets of voice signals were investigated: text reading (2 loudness levels) and sustained vowel (3 levels). The results indicated a high interrater reliability for most perceptual characteristics. Connected speech was evaluated more reliably, especially at the normal level, but both types of voice signals were evaluated reliably, although the reliability for connected speech was somewhat higher than for vowels. Experienced listeners tended to be more consistent in their ratings than did the student raters. Some vocal characteristics achieved acceptable reliability even with a smaller panel of listeners. The perceptual characteristics grouped in 4 factors reflected perceptual dimensions.

Social vision: sustained perceptual enhancement of affective facial cues in social anxiety

PubMed Central

McTeague, Lisa M.; Shumen, Joshua R.; Wieser, Matthias J.; Lang, Peter J.; Keil, Andreas

2010-01-01

Heightened perception of facial cues is at the core of many theories of social behavior and its disorders. In the present study, we continuously measured electrocortical dynamics in human visual cortex, as evoked by happy, neutral, fearful, and angry faces. Thirty-seven participants endorsing high versus low generalized social anxiety (upper and lower tertiles of 2,104 screened undergraduates) viewed naturalistic faces flickering at 17.5 Hz to evoke steady-state visual evoked potentials (ssVEPs), recorded from 129 scalp electrodes. Electrophysiological data were evaluated in the time-frequency domain after linear source space projection using the minimum norm method. Source estimation indicated an early visual cortical origin of the face-evoked ssVEP, which showed sustained amplitude enhancement for emotional expressions specifically in individuals with pervasive social anxiety. Participants in the low symptom group showed no such sensitivity, and a correlational analysis across the entire sample revealed a strong relationship between self-reported interpersonal anxiety/avoidance and enhanced visual cortical response amplitude for emotional, versus neutral expressions. This pattern was maintained across the 3500 ms viewing epoch, suggesting that temporally sustained, heightened perceptual bias towards affective facial cues is associated with generalized social anxiety. PMID:20832490

Object-Based Attention Overrides Perceptual Load to Modulate Visual Distraction

ERIC Educational Resources Information Center

Cosman, Joshua D.; Vecera, Shaun P.

2012-01-01

The ability to ignore task-irrelevant information and overcome distraction is central to our ability to efficiently carry out a number of tasks. One factor shown to strongly influence distraction is the perceptual load of the task being performed; as the perceptual load of task-relevant information processing increases, the likelihood that…

Interactions Between Modality of Working Memory Load and Perceptual Load in Distractor Processing.

PubMed

Koshino, Hideya; Olid, Pilar

2015-01-01

The present study investigated interactions between working memory load and perceptual load. The load theory (Lavie, Hirst, de Fockert, & Viding, 2004 ) claims that perceptual load decreases distractor interference, whereas working memory load increases interference. However, recent studies showed that effects of working memory might depend on the relationship between modalities of working memory and task stimuli. Here, we examined whether the relationship between working memory load and perceptual load would remain the same across modalities. The results of Experiment 1 showed that verbal working memory load did not affect a compatibility effect for low perceptual load, whereas it increased the compatibility effect for high perceptual load. In Experiment 2, the compatibility effect remained the same regardless of visual working memory load. These results suggest that the effects of working memory load and perceptual load depend on the relationship between the modalities of working memory and stimuli.

Avoidance of Emotionally Arousing Stimuli Predicts Social-Perceptual Impairment in Asperger's Syndrome

ERIC Educational Resources Information Center

Corden, Ben; Chilvers, Rebecca; Skuse, David

2008-01-01

We combined eye-tracking technology with a test of facial affect recognition and a measure of self-reported social anxiety in order to explore the aetiology of social-perceptual deficits in Asperger's syndrome (AS). Compared to controls matched for age, IQ and visual-perceptual ability, we found a group of AS adults was impaired in their…

Stimulus recognition occurs under high perceptual load: Evidence from correlated flankers.

PubMed

Cosman, Joshua D; Mordkoff, J Toby; Vecera, Shaun P

2016-12-01

A dominant account of selective attention, perceptual load theory, proposes that when attentional resources are exhausted, task-irrelevant information receives little attention and goes unrecognized. However, the flanker effect-typically used to assay stimulus identification-requires an arbitrary mapping between a stimulus and a response. We looked for failures of flanker identification by using a more-sensitive measure that does not require arbitrary stimulus-response mappings: the correlated flankers effect. We found that flanking items that were task-irrelevant but that correlated with target identity produced a correlated flanker effect. Participants were faster on trials in which the irrelevant flanker had previously correlated with the target than when it did not. Of importance, this correlated flanker effect appeared regardless of perceptual load, occurring even in high-load displays that should have abolished flanker identification. Findings from a standard flanker task replicated the basic perceptual load effect, with flankers not affecting response times under high perceptual load. Our results indicate that task-irrelevant information can be processed to a high level (identification), even under high perceptual load. This challenges a strong account of high perceptual load effects that hypothesizes complete failures of stimulus identification under high perceptual load. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Visual Perceptual Learning and Models.

PubMed

Dosher, Barbara; Lu, Zhong-Lin

2017-09-15

Visual perceptual learning through practice or training can significantly improve performance on visual tasks. Originally seen as a manifestation of plasticity in the primary visual cortex, perceptual learning is more readily understood as improvements in the function of brain networks that integrate processes, including sensory representations, decision, attention, and reward, and balance plasticity with system stability. This review considers the primary phenomena of perceptual learning, theories of perceptual learning, and perceptual learning's effect on signal and noise in visual processing and decision. Models, especially computational models, play a key role in behavioral and physiological investigations of the mechanisms of perceptual learning and for understanding, predicting, and optimizing human perceptual processes, learning, and performance. Performance improvements resulting from reweighting or readout of sensory inputs to decision provide a strong theoretical framework for interpreting perceptual learning and transfer that may prove useful in optimizing learning in real-world applications.

Perceptual Factors Influence Visual Search for Meaningful Symbols in Individuals with Intellectual Disabilities and Down Syndrome or Autism Spectrum Disorders

ERIC Educational Resources Information Center

Wilkinson, Krista M.; McIlvane, William J.

2013-01-01

Augmentative and alternative communication (AAC) systems often supplement oral communication for individuals with intellectual and communication disabilities. Research with preschoolers without disabilities has demonstrated that two visual--perceptual factors influence speed and/or accuracy of finding a target: the internal color and spatial…

Dopamine Modulates the Efficiency of Sensory Evidence Accumulation During Perceptual Decision Making.

PubMed

Beste, Christian; Adelhöfer, Nico; Gohil, Krutika; Passow, Susanne; Roessner, Veit; Li, Shu-Chen

2018-04-02

Perceptual decision making is the process through which available sensory information is gathered and processed to guide our choices. However, the neuropsychopharmacological basis of this important cognitive function is largely elusive. Yet, theoretical considerations suggest that the dopaminergic system may play an important role. In a double-blind, randomized, placebo-controlled study design, we examined the effect of methylphenidate in 2 dosages (0.25 mg/kg and 0.5 mg/kg body weight) in separate groups of healthy young adults. We used a moving dots task in which the coherency of the direction of moving dots stimuli was manipulated in 3 levels (5%, 15%, and 35%). Drift diffusion modelling was applied to behavioral data to capture subprocesses of perceptual decision making. The findings show that only the drift rate (v), reflecting the efficiency of sensory evidence accumulation, but not the decision criterion threshold (a) or the duration of nondecisional processes (Ter), is affected by methylphenidate vs placebo administration. Compared with placebo, administering 0.25 mg/kg methylphenidate increased v, but only in the 35% coherence condition. Administering 0.5 mg/kg methylphenidate did not induce modulations. The data suggest that dopamine selectively modulates the efficacy of evidence accumulation during perceptual decision making. This modulation depends on 2 factors: (1) the degree to which the dopaminergic system is modulated using methylphenidate (i.e., methylphenidate dosage) and (2) the signal-to-noise ratio of the visual information. Dopamine affects sensory evidence accumulation only when dopamine concentration is not shifted beyond an optimal level and the incoming information is less noisy.

Visual perceptual abilities of Chinese-speaking and English-speaking children.

PubMed

Lai, Mun Yee; Leung, Frederick Koon Shing

2012-04-01

This paper reports an investigation of Chinese-speaking and English-speaking children's general visual perceptual abilities. The Developmental Test of Visual Perception was administered to 41 native Chinese-speaking children of mean age 5 yr. 4 mo. in Hong Kong and 35 English-speaking children of mean age 5 yr. 2 mo. in Melbourne. Of interest were the two interrelated components of visual perceptual abilities, namely, motor-reduced visual perceptual and visual-motor integration perceptual abilities, which require either verbal or motoric responses in completing visual tasks. Chinese-speaking children significantly outperformed the English-speaking children on general visual perceptual abilities. When comparing the results of each of the two different components, the Chinese-speaking students' performance on visual-motor integration was far better than that of their counterparts (ES = 2.70), while the two groups of students performed similarly on motor-reduced visual perceptual abilities. Cultural factors such as written language format may be contributing to the enhanced performance of Chinese-speaking children's visual-motor integration abilities, but there may be validity questions in the Chinese version.

Chromatic Perceptual Learning but No Category Effects without Linguistic Input.

PubMed

Grandison, Alexandra; Sowden, Paul T; Drivonikou, Vicky G; Notman, Leslie A; Alexander, Iona; Davies, Ian R L

2016-01-01

Perceptual learning involves an improvement in perceptual judgment with practice, which is often specific to stimulus or task factors. Perceptual learning has been shown on a range of visual tasks but very little research has explored chromatic perceptual learning. Here, we use two low level perceptual threshold tasks and a supra-threshold target detection task to assess chromatic perceptual learning and category effects. Experiment 1 investigates whether chromatic thresholds reduce as a result of training and at what level of analysis learning effects occur. Experiment 2 explores the effect of category training on chromatic thresholds, whether training of this nature is category specific and whether it can induce categorical responding. Experiment 3 investigates the effect of category training on a higher level, lateralized target detection task, previously found to be sensitive to category effects. The findings indicate that performance on a perceptual threshold task improves following training but improvements do not transfer across retinal location or hue. Therefore, chromatic perceptual learning is category specific and can occur at relatively early stages of visual analysis. Additionally, category training does not induce category effects on a low level perceptual threshold task, as indicated by comparable discrimination thresholds at the newly learned hue boundary and adjacent test points. However, category training does induce emerging category effects on a supra-threshold target detection task. Whilst chromatic perceptual learning is possible, learnt category effects appear to be a product of left hemisphere processing, and may require the input of higher level linguistic coding processes in order to manifest.

Chromatic Perceptual Learning but No Category Effects without Linguistic Input

PubMed Central

Grandison, Alexandra; Sowden, Paul T.; Drivonikou, Vicky G.; Notman, Leslie A.; Alexander, Iona; Davies, Ian R. L.

2016-01-01

Perceptual learning involves an improvement in perceptual judgment with practice, which is often specific to stimulus or task factors. Perceptual learning has been shown on a range of visual tasks but very little research has explored chromatic perceptual learning. Here, we use two low level perceptual threshold tasks and a supra-threshold target detection task to assess chromatic perceptual learning and category effects. Experiment 1 investigates whether chromatic thresholds reduce as a result of training and at what level of analysis learning effects occur. Experiment 2 explores the effect of category training on chromatic thresholds, whether training of this nature is category specific and whether it can induce categorical responding. Experiment 3 investigates the effect of category training on a higher level, lateralized target detection task, previously found to be sensitive to category effects. The findings indicate that performance on a perceptual threshold task improves following training but improvements do not transfer across retinal location or hue. Therefore, chromatic perceptual learning is category specific and can occur at relatively early stages of visual analysis. Additionally, category training does not induce category effects on a low level perceptual threshold task, as indicated by comparable discrimination thresholds at the newly learned hue boundary and adjacent test points. However, category training does induce emerging category effects on a supra-threshold target detection task. Whilst chromatic perceptual learning is possible, learnt category effects appear to be a product of left hemisphere processing, and may require the input of higher level linguistic coding processes in order to manifest. PMID:27252669

Perceptual distortion analysis of color image VQ-based coding

NASA Astrophysics Data System (ADS)

Charrier, Christophe; Knoblauch, Kenneth; Cherifi, Hocine

1997-04-01

It is generally accepted that a RGB color image can be easily encoded by using a gray-scale compression technique on each of the three color planes. Such an approach, however, fails to take into account correlations existing between color planes and perceptual factors. We evaluated several linear and non-linear color spaces, some introduced by the CIE, compressed with the vector quantization technique for minimum perceptual distortion. To study these distortions, we measured contrast and luminance of the video framebuffer, to precisely control color. We then obtained psychophysical judgements to measure how well these methods work to minimize perceptual distortion in a variety of color space.

Perceptual learning and human expertise

NASA Astrophysics Data System (ADS)

Kellman, Philip J.; Garrigan, Patrick

2009-06-01

We consider perceptual learning: experience-induced changes in the way perceivers extract information. Often neglected in scientific accounts of learning and in instruction, perceptual learning is a fundamental contributor to human expertise and is crucial in domains where humans show remarkable levels of attainment, such as language, chess, music, and mathematics. In Section 2, we give a brief history and discuss the relation of perceptual learning to other forms of learning. We consider in Section 3 several specific phenomena, illustrating the scope and characteristics of perceptual learning, including both discovery and fluency effects. We describe abstract perceptual learning, in which structural relationships are discovered and recognized in novel instances that do not share constituent elements or basic features. In Section 4, we consider primary concepts that have been used to explain and model perceptual learning, including receptive field change, selection, and relational recoding. In Section 5, we consider the scope of perceptual learning, contrasting recent research, focused on simple sensory discriminations, with earlier work that emphasized extraction of invariance from varied instances in more complex tasks. Contrary to some recent views, we argue that perceptual learning should not be confined to changes in early sensory analyzers. Phenomena at various levels, we suggest, can be unified by models that emphasize discovery and selection of relevant information. In a final section, we consider the potential role of perceptual learning in educational settings. Most instruction emphasizes facts and procedures that can be verbalized, whereas expertise depends heavily on implicit pattern recognition and selective extraction skills acquired through perceptual learning. We consider reasons why perceptual learning has not been systematically addressed in traditional instruction, and we describe recent successful efforts to create a technology of perceptual

Effect Anticipation Affects Perceptual, Cognitive, and Motor Phases of Response Preparation: Evidence from an Event-Related Potential (ERP) Study

PubMed Central

Harrison, Neil R.; Ziessler, Michael

2016-01-01

The anticipation of action effects is a basic process that can be observed even for key-pressing responses in a stimulus-response paradigm. In Ziessler et al.’s (2012) experiments participants first learned arbitrary effects of key-pressing responses. In the test phase an imperative stimulus determined the response, but participants withheld the response until a Go-stimulus appeared. Reaction times (RTs) were shorter if the Go-stimulus was compatible with the learned response effect. This is strong evidence that effect representations were activated during response planning. Here, we repeated the experiment using event-related potentials (ERPs), and we found that Go-stimulus locked ERPs depended on the compatibility relationship between the Go-stimulus and the response effect. In general, this supports the interpretation of the behavioral data. More specifically, differences in the ERPs between compatible and incompatible Go-stimuli were found for the early perceptual P1 component and the later frontal P2 component. P1 differences were found only in the second half of the experiment and for long stimulus onset asynchronies (SOAs) between imperative stimulus and Go-stimulus, i.e., when the effect was fully anticipated and the perceptual system was prepared for the effect-compatible Go-stimulus. P2 amplitudes, likely associated with evaluation and conflict detection, were larger when Go-stimulus and effect were incompatible; presumably, incompatibility increased the difficulty of effect anticipation. Onset of response-locked lateralized readiness potentials (R-LRPs) occurred earlier under incompatible conditions indicating extended motor processing. Together, these results strongly suggest that effect anticipation affects all (i.e., perceptual, cognitive, and motor) phases of response preparation. PMID:26858621

Effect Anticipation Affects Perceptual, Cognitive, and Motor Phases of Response Preparation: Evidence from an Event-Related Potential (ERP) Study.

PubMed

Harrison, Neil R; Ziessler, Michael

2016-01-01

The anticipation of action effects is a basic process that can be observed even for key-pressing responses in a stimulus-response paradigm. In Ziessler et al.'s (2012) experiments participants first learned arbitrary effects of key-pressing responses. In the test phase an imperative stimulus determined the response, but participants withheld the response until a Go-stimulus appeared. Reaction times (RTs) were shorter if the Go-stimulus was compatible with the learned response effect. This is strong evidence that effect representations were activated during response planning. Here, we repeated the experiment using event-related potentials (ERPs), and we found that Go-stimulus locked ERPs depended on the compatibility relationship between the Go-stimulus and the response effect. In general, this supports the interpretation of the behavioral data. More specifically, differences in the ERPs between compatible and incompatible Go-stimuli were found for the early perceptual P1 component and the later frontal P2 component. P1 differences were found only in the second half of the experiment and for long stimulus onset asynchronies (SOAs) between imperative stimulus and Go-stimulus, i.e., when the effect was fully anticipated and the perceptual system was prepared for the effect-compatible Go-stimulus. P2 amplitudes, likely associated with evaluation and conflict detection, were larger when Go-stimulus and effect were incompatible; presumably, incompatibility increased the difficulty of effect anticipation. Onset of response-locked lateralized readiness potentials (R-LRPs) occurred earlier under incompatible conditions indicating extended motor processing. Together, these results strongly suggest that effect anticipation affects all (i.e., perceptual, cognitive, and motor) phases of response preparation.

Attention without awareness: Attentional modulation of perceptual grouping without awareness.

PubMed

Lo, Shih-Yu

2018-04-01

Perceptual grouping is the process through which the perceptual system combines local stimuli into a more global perceptual unit. Previous studies have shown attention to be a modulatory factor for perceptual grouping. However, these studies mainly used explicit measurements, and, thus, whether attention can modulate perceptual grouping without awareness is still relatively unexplored. To clarify the relationship between attention and perceptual grouping, the present study aims to explore how attention interacts with perceptual grouping without awareness. The task was to judge the relative lengths of two centrally presented horizontal bars while a railway-shaped pattern defined by color similarity was presented in the background. Although the observers were unaware of the railway-shaped pattern, their line-length judgment was biased by that pattern, which induced a Ponzo illusion, indicating grouping without awareness. More importantly, an attentional modulatory effect without awareness was manifested as evident by the observer's performance being more often biased when the railway-shaped pattern was formed by an attended color than when it was formed by an unattended one. Also, the attentional modulation effect was shown to be dynamic, being more pronounced with a short presentation time than a longer one. The results of the present study not only clarify the relationship between attention and perceptual grouping but also further contribute to our understanding of attention and awareness by corroborating the dissociation between attention and awareness.

Pupil dilation reflects perceptual selection and predicts subsequent stability in perceptual rivalry

PubMed Central

Einhäuser, Wolfgang; Stout, James; Koch, Christof; Carter, Olivia

2008-01-01

During sustained viewing of an ambiguous stimulus, an individual's perceptual experience will generally switch between the different possible alternatives rather than stay fixed on one interpretation (perceptual rivalry). Here, we measured pupil diameter while subjects viewed different ambiguous visual and auditory stimuli. For all stimuli tested, pupil diameter increased just before the reported perceptual switch and the relative amount of dilation before this switch was a significant predictor of the subsequent duration of perceptual stability. These results could not be explained by blink or eye-movement effects, the motor response or stimulus driven changes in retinal input. Because pupil dilation reflects levels of norepinephrine (NE) released from the locus coeruleus (LC), we interpret these results as suggestive that the LC–NE complex may play the same role in perceptual selection as in behavioral decision making. PMID:18250340

Assessing cognitive dysfunction in Parkinson's disease: An online tool to detect visuo‐perceptual deficits

PubMed Central

Schwarzkopf, Dietrich S.; Bahrami, Bahador; Fleming, Stephen M.; Jackson, Ben M.; Goch, Tristam J. C.; Saygin, Ayse P.; Miller, Luke E.; Pappa, Katerina; Pavisic, Ivanna; Schade, Rachel N.; Noyce, Alastair J.; Crutch, Sebastian J.; O'Keeffe, Aidan G.; Schrag, Anette E.; Morris, Huw R.

2018-01-01

ABSTRACT Background: People with Parkinson's disease (PD) who develop visuo‐perceptual deficits are at higher risk of dementia, but we lack tests that detect subtle visuo‐perceptual deficits and can be performed by untrained personnel. Hallucinations are associated with cognitive impairment and typically involve perception of complex objects. Changes in object perception may therefore be a sensitive marker of visuo‐perceptual deficits in PD. Objective: We developed an online platform to test visuo‐perceptual function. We hypothesised that (1) visuo‐perceptual deficits in PD could be detected using online tests, (2) object perception would be preferentially affected, and (3) these deficits would be caused by changes in perception rather than response bias. Methods: We assessed 91 people with PD and 275 controls. Performance was compared using classical frequentist statistics. We then fitted a hierarchical Bayesian signal detection theory model to a subset of tasks. Results: People with PD were worse than controls at object recognition, showing no deficits in other visuo‐perceptual tests. Specifically, they were worse at identifying skewed images (P < .0001); at detecting hidden objects (P = .0039); at identifying objects in peripheral vision (P < .0001); and at detecting biological motion (P = .0065). In contrast, people with PD were not worse at mental rotation or subjective size perception. Using signal detection modelling, we found this effect was driven by change in perceptual sensitivity rather than response bias. Conclusions: Online tests can detect visuo‐perceptual deficits in people with PD, with object recognition particularly affected. Ultimately, visuo‐perceptual tests may be developed to identify at‐risk patients for clinical trials to slow PD dementia. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society. PMID:29473691

Influence of cue word perceptual information on metamemory accuracy in judgement of learning.

PubMed

Hu, Xiao; Liu, Zhaomin; Li, Tongtong; Luo, Liang

2016-01-01

Previous studies have suggested that perceptual information regarding to-be-remembered words in the study phase affects the accuracy of judgement of learning (JOL). However, few have investigated whether the perceptual information in the JOL phase influences JOL accuracy. This study examined the influence of cue word perceptual information in the JOL phase on immediate and delayed JOL accuracy through changes in cue word font size. In Experiment 1, large-cue word pairs had significantly higher mean JOL magnitude than small-cue word pairs in immediate JOLs and higher relative accuracy than small-cue pairs in delayed JOLs, but font size had no influence on recall performance. Experiment 2 increased the JOL time, and mean JOL magnitude did not reliably differ for large-cue compared with small-cue pairs in immediate JOLs. However, the influence on relative accuracy still existed in delayed JOLs. Experiment 3 increased the familiarity of small-cue words in the delayed JOL phase by adding a lexical decision task. The results indicated that cue word font size no longer affected relative accuracy in delayed JOLs. The three experiments in our study indicated that the perceptual information regarding cue words in the JOL phase affects immediate and delayed JOLs in different ways.

Associative priming in a masked perceptual identification task: evidence for automatic processes.

PubMed

Pecher, Diane; Zeelenberg, René; Raaijmakers, Jeroen G W

2002-10-01

Two experiments investigated the influence of automatic and strategic processes on associative priming effects in a perceptual identification task in which prime-target pairs are briefly presented and masked. In this paradigm, priming is defined as a higher percentage of correctly identified targets for related pairs than for unrelated pairs. In Experiment 1, priming was obtained for mediated word pairs. This mediated priming effect was affected neither by the presence of direct associations nor by the presentation time of the primes, indicating that automatic priming effects play a role in perceptual identification. Experiment 2 showed that the priming effect was not affected by the proportion (.90 vs. .10) of related pairs if primes were presented briefly to prevent their identification. However, a large proportion effect was found when primes were presented for 1000 ms so that they were clearly visible. These results indicate that priming in a masked perceptual identification task is the result of automatic processes and is not affected by strategies. The present paradigm provides a valuable alternative to more commonly used tasks such as lexical decision.

Modelling Peri-Perceptual Brain Processes in a Deep Learning Spiking Neural Network Architecture.

PubMed

Gholami Doborjeh, Zohreh; Kasabov, Nikola; Gholami Doborjeh, Maryam; Sumich, Alexander

2018-06-11

Familiarity of marketing stimuli may affect consumer behaviour at a peri-perceptual processing level. The current study introduces a method for deep learning of electroencephalogram (EEG) data using a spiking neural network (SNN) approach that reveals the complexity of peri-perceptual processes of familiarity. The method is applied to data from 20 participants viewing familiar and unfamiliar logos. The results support the potential of SNN models as novel tools in the exploration of peri-perceptual mechanisms that respond differentially to familiar and unfamiliar stimuli. Specifically, the activation pattern of the time-locked response identified by the proposed SNN model at approximately 200 milliseconds post-stimulus suggests greater connectivity and more widespread dynamic spatio-temporal patterns for familiar than unfamiliar logos. The proposed SNN approach can be applied to study other peri-perceptual or perceptual brain processes in cognitive and computational neuroscience.

Cultural Differences in Perceptual Reorganization in US and Pirahã Adults

PubMed Central

Yoon, Jennifer M. D.; Witthoft, Nathan; Winawer, Jonathan; Frank, Michael C.; Everett, Daniel L.; Gibson, Edward

2014-01-01

Visual illusions and other perceptual phenomena can be used as tools to uncover the otherwise hidden constructive processes that give rise to perception. Although many perceptual processes are assumed to be universal, variable susceptibility to certain illusions and perceptual effects across populations suggests a role for factors that vary culturally. One striking phenomenon is seen with two-tone images—photos reduced to two tones: black and white. Deficient recognition is observed in young children under conditions that trigger automatic recognition in adults. Here we show a similar lack of cue-triggered perceptual reorganization in the Pirahã, a hunter-gatherer tribe with limited exposure to modern visual media, suggesting such recognition is experience- and culture-specific. PMID:25411970

Group benefits in joint perceptual tasks-a review.

PubMed

Wahn, Basil; Kingstone, Alan; König, Peter

2018-05-12

In daily life, humans often perform perceptual tasks together to reach a shared goal. In these situations, individuals may collaborate (e.g., by distributing task demands) to perform the task better than when the task is performed alone (i.e., attain a group benefit). In this review, we identify the factors influencing if, and to what extent, a group benefit is attained and provide a framework of measures to assess group benefits in perceptual tasks. In particular, we integrate findings from two frequently investigated joint perceptual tasks: visuospatial tasks and decision-making tasks. For both task types, we find that an exchange of information between coactors is critical to improve joint performance. Yet, the type of exchanged information and how coactors collaborate differs between tasks. In visuospatial tasks, coactors exchange information about the performed actions to distribute task demands. In perceptual decision-making tasks, coactors exchange their confidence on their individual perceptual judgments to negotiate a joint decision. We argue that these differences can be explained by the task structure: coactors distribute task demands if a joint task allows for a spatial division and stimuli can be accurately processed by one individual. Otherwise, they perform the task individually and then integrate their individual judgments. © 2018 New York Academy of Sciences.

Perceptual and decisional factors influencing the discrimination of inversion in the Thatcher illusion.

PubMed

Cornes, Katherine; Donnelly, Nick; Godwin, Hayward; Wenger, Michael J

2011-06-01

The Thatcher illusion (Thompson, 1980) is considered to be a prototypical illustration of the notion that face perception is dependent on configural processes and representations. We explored this idea by examining the relative contributions of perceptual and decisional processes to the ability of observers to identify the orientation of two classes of forms-faces and churches-and a set of their component features. Observers were presented with upright and inverted images of faces and churches in which the components (eyes, mouth, windows, doors) were presented either upright or inverted. Observers first rated the subjective grotesqueness of all of the images and then performed a complete identification task in which they had to identify the orientation of the overall form and the orientation of each of the interior features. Grotesqueness ratings for both classes of image showed the standard modulation of rated grotesqueness as a function of orientation. The complete identification results revealed violations of both perceptual and decisional separability but failed to reveal any violations of within-stimulus (perceptual) independence. In addition, exploration of a simple bivariate Gaussian signal detection model of the relationship between identification performance and judged grotesqueness suggests that within-stimulus violations of perceptual independence on their own are insufficient for producing the illusion. This lack of evidence for within-stimulus configurality suggests the need for a critical reevaluation of the role of configural processing in the Thatcher illusion. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Dichotomy and perceptual distortions in absolute pitch ability

PubMed Central

Athos, E. Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

2007-01-01

Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a “perceptual magnet” centered at the note “A.” In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the “sharp” direction. These findings speak both to the process of acquisition of AP and to its stability. PMID:17724340

The effects of different combinations of perceptual-motor exercises, music, and vitamin D supplementation on the nerve growth factor in children with high-functioning autism.

PubMed

Moradi, Hadi; Sohrabi, Mehdi; Taheri, Hamidreza; Khodashenas, Ezzat; Movahedi, Ahmadreza

2018-05-01

The present study investigated the effects of different combinations of perceptual-motor exercises, music, and Vitamin D consumption on the nerve growth factor (NGF) in children with high-functioning autism. 48 children with autism, aged between six and nine years, were divided into four groups: Group A- perceptual-motor activities along with music (n = 12); Group B-Vitamin D supplementation (n = 12); Group C-perceptual-motor activities along with music and Vitamin D (n = 12); and Group D-control (n = 12). Participants' blood NGF level was measured before and after the intervention. The results showed a significant improvement in the NGF levels in Groups B and C due to the interventions. Also, in Group A, the NGF levels increased compared to Group D, although this increase was not significant. In addition, the intake of Vitamin D along with perceptual-motor exercises resulted in a significant increase in the levels of NGF compared to Groups A, B and D. These findings suggest that perceptual-motor exercises along with music as well as taking Vitamin D may provide two appropriate interventions for improving NGF in children with autism. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Diabeates Project: Perceptual, Affective and Psychophysiological Effects of Music and Music-Video in a Clinical Exercise Setting.

PubMed

Hutchinson, Jasmin C; Karageorghis, Costas I; Black, Jessica D

2017-02-01

The purpose of this study was to examine the effects of music and music-video on perceptual (attentional focus, rated perceived exertion), affective (affective valence and enjoyment) and psychophysiological (blood glucose, heart rate) variables in outpatients attending a diabetes exercise clinic. Participants were 24 females (age = 66.0 ± 8.5 years) enrolled in a supervised exercise program for people with diabetes. They engaged in mixed-modality exercise sessions that included a standardized combination of flexibility, aerobic and resistance activities under conditions of music, music-video and control. Analyses revealed a main effect of condition on attentional focus and affect during aerobic exercise only. The music-video condition elicited the highest level of attentional dissociation, while affective valence was more positive in the 2 experimental conditions when compared to control. Rated perceived exertion and heart rate did not differ across conditions. Measures of exercise enjoyment indicated a main effect of condition wherein scores were higher with the music-video condition when compared to control. There was an acute glucose-lowering effect of exercise in all conditions. Results lend support to the notion that auditory and visual stimuli can enhance affective responses to exercise in a clinical setting. This may have meaningful implications for adherence, given the link between affective judgements and future behaviour in an exercise context. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

The influence of schizotypal traits on attention under high perceptual load.

PubMed

Stotesbury, Hanne; Gaigg, Sebastian B; Kirhan, Saim; Haenschel, Corinna

2018-03-01

Schizophrenia Spectrum Disorders (SSD) are known to be characterised by abnormalities in attentional processes, but there are inconsistencies in the literature that remain unresolved. This article considers whether perceptual resource limitations play a role in moderating attentional abnormalities in SSD. According to perceptual load theory, perceptual resource limitations can lead to attenuated or superior performance on dual-task paradigms depending on whether participants are required to process, or attempt to ignore, secondary stimuli. If SSD is associated with perceptual resource limitations, and if it represents the extreme end of an otherwise normally distributed neuropsychological phenotype, schizotypal traits in the general population should lead to disproportionate performance costs on dual-task paradigms as a function of the perceptual task demands. To test this prediction, schizotypal traits were quantified via the Schizotypal Personality Questionnaire (SPQ) in 74 healthy volunteers, who also completed a dual-task signal detection paradigm that required participants to detect central and peripheral stimuli across conditions that varied in the overall number of stimuli presented. The results confirmed decreasing performance as the perceptual load of the task increased. More importantly, significant correlations between SPQ scores and task performance confirmed that increased schizotypal traits, particularly in the cognitive-perceptual domain, are associated with greater performance decrements under increasing perceptual load. These results confirm that attentional difficulties associated with SSD extend sub-clinically into the general population and suggest that cognitive-perceptual schizotypal traits may represent a risk factor for difficulties in the regulation of attention under increasing perceptual load.

Neurofeedback training of gamma band oscillations improves perceptual processing.

PubMed

Salari, Neda; Büchel, Christian; Rose, Michael

2014-10-01

In this study, a noninvasive electroencephalography-based neurofeedback method is applied to train volunteers to deliberately increase gamma band oscillations (40 Hz) in the visual cortex. Gamma band oscillations in the visual cortex play a functional role in perceptual processing. In a previous study, we were able to demonstrate that gamma band oscillations prior to stimulus presentation have a significant influence on perceptual processing of visual stimuli. In the present study, we aimed to investigate longer lasting effects of gamma band neurofeedback training on perceptual processing. For this purpose, a feedback group was trained to modulate oscillations in the gamma band, while a control group participated in a task with an identical design setting but without gamma band feedback. Before and after training, both groups participated in a perceptual object detection task and a spatial attention task. Our results clearly revealed that only the feedback group but not the control group exhibited a visual processing advantage and an increase in oscillatory gamma band activity in the pre-stimulus period of the processing of the visual object stimuli after the neurofeedback training. Results of the spatial attention task showed no difference between the groups, which underlines the specific role of gamma band oscillations for perceptual processing. In summary, our results show that modulation of gamma band activity selectively affects perceptual processing and therefore supports the relevant role of gamma band activity for this specific process. Furthermore, our results demonstrate the eligibility of gamma band oscillations as a valuable tool for neurofeedback applications.

Perceptual Factors Influence Visual Search for Meaningful Symbols In Individuals with Intellectual Disabilities and Down Syndrome or Autism Spectrum Disorders

PubMed Central

Wilkinson, Krista M.; McIlvane, William J.

2013-01-01

Augmentative and alternative communication (AAC) systems often supplement oral communication of individuals with intellectual and communication disabilities. Research with nondisabled preschoolers has demonstrated that two visual perceptual factors influence speed and/or accuracy of finding a target - the internal color and spatial organization of symbols. Twelve participants with Down syndrome and 12 with ASD underwent two search tasks. In one, the symbols were clustered by internal color; in the other the identical symbols had no arrangement cue. Visual search was superior in participants with ASD compared to those with Down syndrome. In both groups, responses were significantly faster when the symbols were clustered by internal color. Construction of aided AAC displays may benefit from attention to their physical/perceptual features. PMID:24245729

Perceptual representation and effectiveness of local figure–ground cues in natural contours

PubMed Central

Sakai, Ko; Matsuoka, Shouhei; Kurematsu, Ken; Hatori, Yasuhiro

2015-01-01

A contour shape strongly influences the perceptual segregation of a figure from the ground. We investigated the contribution of local contour shape to figure–ground segregation. Although previous studies have reported local contour features that evoke figure–ground perception, they were often image features and not necessarily perceptual features. First, we examined whether contour features, specifically, convexity, closure, and symmetry, underlie the perceptual representation of natural contour shapes. We performed similarity tests between local contours, and examined the contribution of the contour features to the perceptual similarities between the contours. The local contours were sampled from natural contours so that their distribution was uniform in the space composed of the three contour features. This sampling ensured the equal appearance frequency of the factors and a wide variety of contour shapes including those comprised of contradictory factors that induce figure in the opposite directions. This sampling from natural contours is advantageous in order to randomly pickup a variety of contours that satisfy a wide range of cue combinations. Multidimensional scaling analyses showed that the combinations of convexity, closure, and symmetry contribute to perceptual similarity, thus they are perceptual quantities. Second, we examined whether the three features contribute to local figure–ground perception. We performed psychophysical experiments to judge the direction of the figure along the local contours, and examined the contribution of the features to the figure–ground judgment. Multiple linear regression analyses showed that closure was a significant factor, but that convexity and symmetry were not. These results indicate that closure is dominant in the local figure–ground perception with natural contours when the other cues coexist with equal probability including contradictory cases. PMID:26579057

Perceptual representation and effectiveness of local figure-ground cues in natural contours.

PubMed

Sakai, Ko; Matsuoka, Shouhei; Kurematsu, Ken; Hatori, Yasuhiro

2015-01-01

A contour shape strongly influences the perceptual segregation of a figure from the ground. We investigated the contribution of local contour shape to figure-ground segregation. Although previous studies have reported local contour features that evoke figure-ground perception, they were often image features and not necessarily perceptual features. First, we examined whether contour features, specifically, convexity, closure, and symmetry, underlie the perceptual representation of natural contour shapes. We performed similarity tests between local contours, and examined the contribution of the contour features to the perceptual similarities between the contours. The local contours were sampled from natural contours so that their distribution was uniform in the space composed of the three contour features. This sampling ensured the equal appearance frequency of the factors and a wide variety of contour shapes including those comprised of contradictory factors that induce figure in the opposite directions. This sampling from natural contours is advantageous in order to randomly pickup a variety of contours that satisfy a wide range of cue combinations. Multidimensional scaling analyses showed that the combinations of convexity, closure, and symmetry contribute to perceptual similarity, thus they are perceptual quantities. Second, we examined whether the three features contribute to local figure-ground perception. We performed psychophysical experiments to judge the direction of the figure along the local contours, and examined the contribution of the features to the figure-ground judgment. Multiple linear regression analyses showed that closure was a significant factor, but that convexity and symmetry were not. These results indicate that closure is dominant in the local figure-ground perception with natural contours when the other cues coexist with equal probability including contradictory cases.

Viewing Olfactory Affective Responses Through the Sniff Prism: Effect of Perceptual Dimensions and Age on Olfactomotor Responses to Odors

PubMed Central

Ferdenzi, Camille; Fournel, Arnaud; Thévenet, Marc; Coppin, Géraldine; Bensafi, Moustafa

2015-01-01

Sniffing, which is the active sampling of olfactory information through the nasal cavity, is part of the olfactory percept. It is influenced by stimulus properties, affects how an odor is perceived, and is sufficient (without an odor being present) to activate the olfactory cortex. However, many aspects of the affective correlates of sniffing behavior remain unclear, in particular the modulation of volume and duration as a function of odor hedonics. The present study used a wide range of odorants with contrasted hedonic valence to test: (1) which psychophysical function best describes the relationship between sniffing characteristics and odor hedonics (e.g., linear, or polynomial); (2) whether sniffing characteristics are sensitive to more subtle variations in pleasantness than simple pleasant-unpleasant contrast; (3) how sensitive sniffing is to other perceptual dimensions of odors such as odor familiarity or edibility; and (4) whether the sniffing/hedonic valence relationship is valid in other populations than young adults, such as the elderly. Four experiments were conducted, using 16–48 odorants each, and recruiting a total of 102 participants, including a group of elderly people. Results of the four experiments were very consistent in showing that sniffing was sensitive to subtle variations in unpleasantness but not to subtle variations in pleasantness, and that, the more unpleasant the odor, the more limited the spontaneous sampling of olfactory information through the nasal cavity (smaller volume, shorter duration). This also applied, although to a lesser extent, to elderly participants. Relationships between sniffing and other perceptual dimensions (familiarity, edibility) were less clear. It was concluded that sniffing behavior might be involved in adaptive responses protecting the subject from possibly harmful substances. PMID:26635683

Perceptual attributes for the comparison of head-related transfer functions.

PubMed

Simon, Laurent S R; Zacharov, Nick; Katz, Brian F G

2016-11-01

The benefit of using individual head-related transfer functions (HRTFs) in binaural audio is well documented with regards to improving localization precision. However, with the increased use of binaural audio in more complex scene renderings, cognitive studies, and virtual and augmented reality simulations, the perceptual impact of HRTF selection may go beyond simple localization. In this study, the authors develop a list of attributes which qualify the perceived differences between HRTFs, providing a qualitative understanding of the perceptual variance of non-individual binaural renderings. The list of attributes was designed using a Consensus Vocabulary Protocol elicitation method. Participants followed an Individual Vocabulary Protocol elicitation procedure, describing the perceived differences between binaural stimuli based on binauralized extracts of multichannel productions. This was followed by an automated lexical reduction and a series of consensus group meetings during which participants agreed on a list of relevant attributes. Finally, the proposed list of attributes was then evaluated through a listening test, leading to eight valid perceptual attributes for describing the perceptual dimensions affected by HRTF set variations.

Influence of Perceptual Saliency Hierarchy on Learning of Language Structures: An Artificial Language Learning Experiment

PubMed Central

Gong, Tao; Lam, Yau W.; Shuai, Lan

2016-01-01

Psychological experiments have revealed that in normal visual perception of humans, color cues are more salient than shape cues, which are more salient than textural patterns. We carried out an artificial language learning experiment to study whether such perceptual saliency hierarchy (color > shape > texture) influences the learning of orders regulating adjectives of involved visual features in a manner either congruent (expressing a salient feature in a salient part of the form) or incongruent (expressing a salient feature in a less salient part of the form) with that hierarchy. Results showed that within a few rounds of learning participants could learn the compositional segments encoding the visual features and the order between them, generalize the learned knowledge to unseen instances with the same or different orders, and show learning biases for orders that are congruent with the perceptual saliency hierarchy. Although the learning performances for both the biased and unbiased orders became similar given more learning trials, our study confirms that this type of individual perceptual constraint could contribute to the structural configuration of language, and points out that such constraint, as well as other factors, could collectively affect the structural diversity in languages. PMID:28066281

Influence of Perceptual Saliency Hierarchy on Learning of Language Structures: An Artificial Language Learning Experiment.

PubMed

Gong, Tao; Lam, Yau W; Shuai, Lan

2016-01-01

Psychological experiments have revealed that in normal visual perception of humans, color cues are more salient than shape cues, which are more salient than textural patterns. We carried out an artificial language learning experiment to study whether such perceptual saliency hierarchy (color > shape > texture) influences the learning of orders regulating adjectives of involved visual features in a manner either congruent (expressing a salient feature in a salient part of the form) or incongruent (expressing a salient feature in a less salient part of the form) with that hierarchy. Results showed that within a few rounds of learning participants could learn the compositional segments encoding the visual features and the order between them, generalize the learned knowledge to unseen instances with the same or different orders, and show learning biases for orders that are congruent with the perceptual saliency hierarchy. Although the learning performances for both the biased and unbiased orders became similar given more learning trials, our study confirms that this type of individual perceptual constraint could contribute to the structural configuration of language, and points out that such constraint, as well as other factors, could collectively affect the structural diversity in languages.

Emotional memory is perceptual.

PubMed

Arntz, Arnoud; de Groot, Corlijn; Kindt, Merel

2005-03-01

In two experiments it was investigated which aspects of memory are influenced by emotion. Using a framework proposed by Roediger (American Psychologist 45 (1990) 1043-1056), two dimensions relevant for memory were distinguished the implicit-explicit distinction, and the perceptual versus conceptual distinction. In week 1, subjects viewed a series of slides accompanied with a spoken story in either of the two versions, a neutral version, or a version with an emotional mid-phase. In week 2, memory performance for the slides and story was assessed unexpectedly. A free recall test revealed superior memory in the emotional condition for the story's mid-phase stimuli as compared to the neutral condition, replicating earlier findings. Furthermore, memory performance was assessed using tests that systematically assessed all combinations of implicit versus explicit and perceptual versus conceptual memory. Subjects who had listened to the emotional story had superior perceptual memory, on both implicit and explicit level, compared to those who had listened to the neutral story. Conceptual memory was not superior in the emotional condition. The results suggest that emotion specifically promotes perceptual memory, probably by better encoding of perceptual aspects of emotional experiences. This might be related to the prominent position of perceptual memories in traumatic memory, manifest in intrusions, nightmares and reliving experiences.

Improved segregation of simultaneous talkers differentially affects perceptual and cognitive capacity demands for recognizing speech in competing speech.

PubMed

Francis, Alexander L

2010-02-01

Perception of speech in competing speech is facilitated by spatial separation of the target and distracting speech, but this benefit may arise at either a perceptual or a cognitive level of processing. Load theory predicts different effects of perceptual and cognitive (working memory) load on selective attention in flanker task contexts, suggesting that this paradigm may be used to distinguish levels of interference. Two experiments examined interference from competing speech during a word recognition task under different perceptual and working memory loads in a dual-task paradigm. Listeners identified words produced by a talker of one gender while ignoring a talker of the other gender. Perceptual load was manipulated using a nonspeech response cue, with response conditional upon either one or two acoustic features (pitch and modulation). Memory load was manipulated with a secondary task consisting of one or six visually presented digits. In the first experiment, the target and distractor were presented at different virtual locations (0 degrees and 90 degrees , respectively), whereas in the second, all the stimuli were presented from the same apparent location. Results suggest that spatial cues improve resistance to distraction in part by reducing working memory demand.

Skilled deaf readers have an enhanced perceptual span in reading.

PubMed

Bélanger, Nathalie N; Slattery, Timothy J; Mayberry, Rachel I; Rayner, Keith

2012-07-01

Recent evidence suggests that, compared with hearing people, deaf people have enhanced visual attention to simple stimuli viewed in the parafovea and periphery. Although a large part of reading involves processing the fixated words in foveal vision, readers also utilize information in parafoveal vision to preprocess upcoming words and decide where to look next. In the study reported here, we investigated whether auditory deprivation affects low-level visual processing during reading by comparing the perceptual span of deaf signers who were skilled and less-skilled readers with the perceptual span of skilled hearing readers. Compared with hearing readers, the two groups of deaf readers had a larger perceptual span than would be expected given their reading ability. These results provide the first evidence that deaf readers' enhanced attentional allocation to the parafovea is used during complex cognitive tasks, such as reading.

Perceptual Aspects of Motor Performance.

ERIC Educational Resources Information Center

Gallahue, David L.

Perceptual-motor functioning is a cyclic process involving: (1) organizing incoming sensory stimuli with past or stored perceptual information; (2) making motor (internal) decisions based on the combination of sensory (present) and perceptual (past) information; (3) executing the actual movement (observable act) itself; and (4) evaluating the act…

Perceptual learning in sensorimotor adaptation.

PubMed

Darainy, Mohammad; Vahdat, Shahabeddin; Ostry, David J

2013-11-01

Motor learning often involves situations in which the somatosensory targets of movement are, at least initially, poorly defined, as for example, in learning to speak or learning the feel of a proper tennis serve. Under these conditions, motor skill acquisition presumably requires perceptual as well as motor learning. That is, it engages both the progressive shaping of sensory targets and associated changes in motor performance. In the present study, we test the idea that perceptual learning alters somatosensory function and in so doing produces changes to human motor performance and sensorimotor adaptation. Subjects in these experiments undergo perceptual training in which a robotic device passively moves the subject's arm on one of a set of fan-shaped trajectories. Subjects are required to indicate whether the robot moved the limb to the right or the left and feedback is provided. Over the course of training both the perceptual boundary and acuity are altered. The perceptual learning is observed to improve both the rate and extent of learning in a subsequent sensorimotor adaptation task and the benefits persist for at least 24 h. The improvement in the present studies varies systematically with changes in perceptual acuity and is obtained regardless of whether the perceptual boundary shift serves to systematically increase or decrease error on subsequent movements. The beneficial effects of perceptual training are found to be substantially dependent on reinforced decision-making in the sensory domain. Passive-movement training on its own is less able to alter subsequent learning in the motor system. Overall, this study suggests perceptual learning plays an integral role in motor learning.

Picture-Perfect Is Not Perfect for Metamemory: Testing the Perceptual Fluency Hypothesis with Degraded Images

ERIC Educational Resources Information Center

Besken, Miri

2016-01-01

The perceptual fluency hypothesis claims that items that are easy to perceive at encoding induce an illusion that they will be easier to remember, despite the finding that perception does not generally affect recall. The current set of studies tested the predictions of the perceptual fluency hypothesis with a picture generation manipulation.…

Acetylcholine and Olfactory Perceptual Learning

ERIC Educational Resources Information Center

Wilson, Donald A.; Fletcher, Max L.; Sullivan, Regina M.

2004-01-01

Olfactory perceptual learning is a relatively long-term, learned increase in perceptual acuity, and has been described in both humans and animals. Data from recent electrophysiological studies have indicated that olfactory perceptual learning may be correlated with changes in odorant receptive fields of neurons in the olfactory bulb and piriform…

Perceptual dimensions differentiate emotions.

PubMed

Cavanaugh, Lisa A; MacInnis, Deborah J; Weiss, Allen M

2015-08-26

Individuals often describe objects in their world in terms of perceptual dimensions that span a variety of modalities; the visual (e.g., brightness: dark-bright), the auditory (e.g., loudness: quiet-loud), the gustatory (e.g., taste: sour-sweet), the tactile (e.g., hardness: soft vs. hard) and the kinaesthetic (e.g., speed: slow-fast). We ask whether individuals use perceptual dimensions to differentiate emotions from one another. Participants in two studies (one where respondents reported on abstract emotion concepts and a second where they reported on specific emotion episodes) rated the extent to which features anchoring 29 perceptual dimensions (e.g., temperature, texture and taste) are associated with 8 emotions (anger, fear, sadness, guilt, contentment, gratitude, pride and excitement). Results revealed that in both studies perceptual dimensions differentiate positive from negative emotions and high arousal from low arousal emotions. They also differentiate among emotions that are similar in arousal and valence (e.g., high arousal negative emotions such as anger and fear). Specific features that anchor particular perceptual dimensions (e.g., hot vs. cold) are also differentially associated with emotions.

Cognitive-Perceptual Examination of Remediation Approaches to Hypokinetic Dysarthria

ERIC Educational Resources Information Center

McAuliffe, Megan J.; Kerr, Sarah E.; Gibson, Elizabeth M. R.; Anderson, Tim; LaShell, Patrick J.

2014-01-01

Purpose: To determine how increased vocal loudness and reduced speech rate affect listeners' cognitive-perceptual processing of hypokinetic dysarthric speech associated with Parkinson's disease. Method: Fifty-one healthy listener participants completed a speech perception experiment. Listeners repeated phrases produced by 5 individuals…

Inductive generalization with familiar categories: developmental changes in children's reliance on perceptual similarity and kind information

PubMed Central

Godwin, Karrie E.; Fisher, Anna V.

2015-01-01

Inductive generalization is ubiquitous in human cognition; however, the factors underpinning this ability early in development remain contested. The present study was designed to (1) test the predictions of the naïve theory and a similarity-based account and (2) examine the mechanism by which labels promote induction. In Experiment 1, 3- to 5-year-old children made inferences about highly familiar categories. The results were not fully consistent with either theoretical account. In contrast to the predictions of the naïve theory approach, the youngest children in the study did not ignore perceptually compelling lures in favor of category-match items; in contrast to the predictions of the similarity-based account, no group of participants favored perceptually compelling lures in the presence of dissimilar-looking category-match items. In Experiment 2 we investigated the mechanisms by which labels promote induction by examining the influence of different label types, namely category labels (e.g., the target and category-match both labeled as bird) and descriptor labels (e.g., the target and the perceptual lure both labeled as brown) on induction performance. In contrast to the predictions of the naïve theory approach, descriptor labels but not category labels affected induction in 3-year-old children. Consistent with the predictions of the similarity-based account, descriptor labels affected the performance of children in all age groups included in the study. The implications of these findings for the developmental account of induction are discussed. PMID:26217254

Inductive generalization with familiar categories: developmental changes in children's reliance on perceptual similarity and kind information.

PubMed

Godwin, Karrie E; Fisher, Anna V

2015-01-01

Inductive generalization is ubiquitous in human cognition; however, the factors underpinning this ability early in development remain contested. The present study was designed to (1) test the predictions of the naïve theory and a similarity-based account and (2) examine the mechanism by which labels promote induction. In Experiment 1, 3- to 5-year-old children made inferences about highly familiar categories. The results were not fully consistent with either theoretical account. In contrast to the predictions of the naïve theory approach, the youngest children in the study did not ignore perceptually compelling lures in favor of category-match items; in contrast to the predictions of the similarity-based account, no group of participants favored perceptually compelling lures in the presence of dissimilar-looking category-match items. In Experiment 2 we investigated the mechanisms by which labels promote induction by examining the influence of different label types, namely category labels (e.g., the target and category-match both labeled as bird) and descriptor labels (e.g., the target and the perceptual lure both labeled as brown) on induction performance. In contrast to the predictions of the naïve theory approach, descriptor labels but not category labels affected induction in 3-year-old children. Consistent with the predictions of the similarity-based account, descriptor labels affected the performance of children in all age groups included in the study. The implications of these findings for the developmental account of induction are discussed.

Perceptual processing of natural scenes at rapid rates: Effects of complexity, content, and emotional arousal

PubMed Central

Bradley, Margaret M.; Lang, Peter J.

2013-01-01

During rapid serial visual presentation (RSVP), the perceptual system is confronted with a rapidly changing array of sensory information demanding resolution. At rapid rates of presentation, previous studies have found an early (e.g., 150–280 ms) negativity over occipital sensors that is enhanced when emotional, as compared with neutral, pictures are viewed, suggesting facilitated perception. In the present study, we explored how picture composition and the presence of people in the image affect perceptual processing of pictures of natural scenes. Using RSVP, pictures that differed in perceptual composition (figure–ground or scenes), content (presence of people or not), and emotional content (emotionally arousing or neutral) were presented in a continuous stream for 330 ms each with no intertrial interval. In both subject and picture analyses, all three variables affected the amplitude of occipital negativity, with the greatest enhancement for figure–ground compositions (as compared with scenes), irrespective of content and emotional arousal, supporting an interpretation that ease of perceptual processing is associated with enhanced occipital negativity. Viewing emotional pictures prompted enhanced negativity only for pictures that depicted people, suggesting that specific features of emotionally arousing images are associated with facilitated perceptual processing, rather than all emotional content. PMID:23780520

Perceptual Learning Style Preferences among Iranian Graduate Students

ERIC Educational Resources Information Center

Naserieh, Farid; Sarab, Mohammad Reza Anani

2013-01-01

Research suggests that a host of cognitive, affective, and perceptual variables are at work when individuals go about the task of second or foreign language learning. Among these variables are learning styles that are habitual ways of perceiving, processing, and storing information. This study was conducted as a response to Isemonger and…

Understanding Perceptual Differences; An Exploration of Neurological-Perceptual Roots of Learning Disabilities with Suggestions for Diagnosis and Treatment.

ERIC Educational Resources Information Center

Monroe, George E.

In exploring the bases of learning disabilities, the following areas are considered: a working definition of perceptual handicaps; the relationship of perceptual handicaps to IQ; diagnosing perceptual handicaps; effective learning experiences for the perceptually handicapped child; and recommendations for developing new curricula. The appendixes…

The Facespan-the perceptual span for face recognition.

PubMed

Papinutto, Michael; Lao, Junpeng; Ramon, Meike; Caldara, Roberto; Miellet, Sébastien

2017-05-01

In reading, the perceptual span is a well-established concept that refers to the amount of information that can be read in a single fixation. Surprisingly, despite extensive empirical interest in determining the perceptual strategies deployed to process faces and an ongoing debate regarding the factors or mechanism(s) underlying efficient face processing, the perceptual span for faces-the Facespan-remains undetermined. To address this issue, we applied the gaze-contingent Spotlight technique implemented in an old-new face recognition paradigm. This procedure allowed us to parametrically vary the amount of facial information available at a fixated location in order to determine the minimal aperture size at which face recognition performance plateaus. As expected, accuracy increased nonlinearly with spotlight size apertures. Analyses of Structural Similarity comparing the available information during spotlight and natural viewing conditions indicate that the Facespan-the minimum spatial extent of preserved facial information leading to comparable performance as in natural viewing-encompasses 7° of visual angle in our viewing conditions (size of the face stimulus: 15.6°; viewing distance: 70 cm), which represents 45% of the face. The present findings provide a benchmark for future investigations that will address if and how the Facespan is modulated by factors such as cultural, developmental, idiosyncratic, or task-related differences.

Perceptual pitch deficits coexist with pitch production difficulties in music but not Mandarin speech

PubMed Central

Yang, Wu-xia; Feng, Jie; Huang, Wan-ting; Zhang, Cheng-xiang; Nan, Yun

2014-01-01

Congenital amusia is a musical disorder that mainly affects pitch perception. Among Mandarin speakers, some amusics also have difficulties in processing lexical tones (tone agnosics). To examine to what extent these perceptual deficits may be related to pitch production impairments in music and Mandarin speech, eight amusics, eight tone agnosics, and 12 age- and IQ-matched normal native Mandarin speakers were asked to imitate music note sequences and Mandarin words of comparable lengths. The results indicated that both the amusics and tone agnosics underperformed the controls on musical pitch production. However, tone agnosics performed no worse than the amusics, suggesting that lexical tone perception deficits may not aggravate musical pitch production difficulties. Moreover, these three groups were all able to imitate lexical tones with perfect intelligibility. Taken together, the current study shows that perceptual musical pitch and lexical tone deficits might coexist with musical pitch production difficulties. But at the same time these perceptual pitch deficits might not affect lexical tone production or the intelligibility of the speech words that were produced. The perception-production relationship for pitch among individuals with perceptual pitch deficits may be, therefore, domain-dependent. PMID:24474944

The development of sentence interpretation: effects of perceptual, attentional and semantic interference.

PubMed

Leech, Robert; Aydelott, Jennifer; Symons, Germaine; Carnevale, Julia; Dick, Frederic

2007-11-01

How does the development and consolidation of perceptual, attentional, and higher cognitive abilities interact with language acquisition and processing? We explored children's (ages 5-17) and adults' (ages 18-51) comprehension of morphosyntactically varied sentences under several competing speech conditions that varied in the degree of attentional demands, auditory masking, and semantic interference. We also evaluated the relationship between subjects' syntactic comprehension and their word reading efficiency and general 'speed of processing'. We found that the interactions between perceptual and attentional processes and complex sentence interpretation changed considerably over the course of development. Perceptual masking of the speech signal had an early and lasting impact on comprehension, particularly for more complex sentence structures. In contrast, increased attentional demand in the absence of energetic auditory masking primarily affected younger children's comprehension of difficult sentence types. Finally, the predictability of syntactic comprehension abilities by external measures of development and expertise is contingent upon the perceptual, attentional, and semantic milieu in which language processing takes place.

Perceptual Learning of Acoustic Noise by Individuals with Dyslexia

ERIC Educational Resources Information Center

Agus, Trevor R.; Carrión-Castillo, Amaia; Pressnitzer, Daniel; Ramus, Franck

2014-01-01

Purpose: A phonological deficit is thought to affect most individuals with developmental dyslexia. The present study addresses whether the phonological deficit is caused by difficulties with perceptual learning of fine acoustic details. Method: A demanding test of nonverbal auditory memory, "noise learning," was administered to both…

Atypicalities in Perceptual Adaptation in Autism Do Not Extend to Perceptual Causality

PubMed Central

Karaminis, Themelis; Turi, Marco; Neil, Louise; Badcock, Nicholas A.; Burr, David; Pellicano, Elizabeth

2015-01-01

A recent study showed that adaptation to causal events (collisions) in adults caused subsequent events to be less likely perceived as causal. In this study, we examined if a similar negative adaptation effect for perceptual causality occurs in children, both typically developing and with autism. Previous studies have reported diminished adaptation for face identity, facial configuration and gaze direction in children with autism. To test whether diminished adaptive coding extends beyond high-level social stimuli (such as faces) and could be a general property of autistic perception, we developed a child-friendly paradigm for adaptation of perceptual causality. We compared the performance of 22 children with autism with 22 typically developing children, individually matched on age and ability (IQ scores). We found significant and equally robust adaptation aftereffects for perceptual causality in both groups. There were also no differences between the two groups in their attention, as revealed by reaction times and accuracy in a change-detection task. These findings suggest that adaptation to perceptual causality in autism is largely similar to typical development and, further, that diminished adaptive coding might not be a general characteristic of autism at low levels of the perceptual hierarchy, constraining existing theories of adaptation in autism. PMID:25774507

Perceptual fluency and affect without recognition.

PubMed

Anand, P; Sternthal, B

1991-05-01

A dichotic listening task was used to investigate the affect-without-recognition phenomenon. Subjects performed a distractor task by responding to the information presented in one ear while ignoring the target information presented in the other ear. The subjects' recognition of and affect toward the target information as well as toward foils was measured. The results offer evidence for the affect-without-recognition phenomenon. Furthermore, the data suggest that the subjects' affect toward the stimuli depended primarily on the extent to which the stimuli were perceived as familiar (i.e., subjective familiarity), and this perception was influenced by the ear in which the distractor or the target information was presented. These data are interpreted in terms of current models of recognition memory and hemispheric lateralization.

Perceptual-center modeling is affected by including acoustic rate-of-change modulations.

PubMed

Harsin, C A

1997-02-01

This study investigated the acoustic correlates of perceptual centers (p-centers) in CV and VC syllables and developed an acoustic p-center model. In Part 1, listeners located syllables' p-centers by a method-of-adjustment procedure. The CV syllables contained the consonants /s/,/r/,/n/,/t/,/d/,/k/, and /g/; the VCs, the consonants /s/,/r/, and /n/. The vowel in all syllables was /a/. The results of this experiment replicated and extended previous findings regarding the effects of phonetic variation on p-centers. In Part 2, a digital signal processing procedure was used to acoustically model p-center perception. Each stimulus was passed through a six-band digital filter, and the outputs were processed to derive low-frequency modulation components. These components were weighted according to a perceived modulation magnitude function and recombined to create six psychoacoustic envelopes containing modulation energies from 3 to 47 Hz. In this analysis, p-centers were found to be highly correlated with the time-weighted function of the rate-of-change in the psychoacoustic envelopes, multiplied by the psychoacoustic envelope magnitude increment. The results were interpreted as suggesting (1) the probable role of low-frequency energy modulations in p-center perception, and (2) the presence of perceptual processes that integrate multiple articulatory events into a single syllabic event.

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…

Neural representations of relevant and irrelevant features in perceptual decision making

PubMed Central

Kayser, Andrew S.; Erickson, Drew T.; Buchsbaum, Bradley R.; D'Esposito, Mark

2010-01-01

Although perceptual decision-making activates a network of brain areas involved in sensory, integrative, and motor functions, circuit activity can clearly be modulated by factors beyond the stimulus. Of particular interest is to understand how the network is modulated by top-down factors such as attention. Here we demonstrate in a motion coherence task that selective attention produces marked changes in the BOLD response in a subset of regions within a human perceptual decision-making circuit. Specifically, when motion is attended, the BOLD response decreases with increasing motion coherence in many regions, including the motion-sensitive area MT+, the intraparietal sulcus (IPS), and the inferior frontal sulcus (IFS). However, when motion is ignored, the negative parametric response in a subset of this circuit becomes positive. Through both modeling and connectivity analyses, we demonstrate that this inversion both reflects a top-down influence and segregates attentional from accumulation regions, thereby permitting us to further delineate the contributions of different regions to the perceptual decision. PMID:21106817

Speaker-independent factors affecting the perception of foreign accent in a second languagea)

PubMed Central

Levi, Susannah V.; Winters, Stephen J.; Pisoni, David B.

2012-01-01

Previous research on foreign accent perception has largely focused on speaker-dependent factors such as age of learning and length of residence. Factors that are independent of a speaker’s language learning history have also been shown to affect perception of second language speech. The present study examined the effects of two such factors—listening context and lexical frequency—on the perception of foreign-accented speech. Listeners rated foreign accent in two listening contexts: auditory-only, where listeners only heard the target stimuli, and auditory+orthography, where listeners were presented with both an auditory signal and an orthographic display of the target word. Results revealed that higher frequency words were consistently rated as less accented than lower frequency words. The effect of the listening context emerged in two interactions: the auditory +orthography context reduced the effects of lexical frequency, but increased the perceived differences between native and non-native speakers. Acoustic measurements revealed some production differences for words of different levels of lexical frequency, though these differences could not account for all of the observed interactions from the perceptual experiment. These results suggest that factors independent of the speakers’ actual speech articulations can influence the perception of degree of foreign accent. PMID:17471745

Integrated approaches to perceptual learning.

PubMed

Jacobs, Robert A

2010-04-01

New technologies and new ways of thinking have recently led to rapid expansions in the study of perceptual learning. We describe three themes shared by many of the nine articles included in this topic on Integrated Approaches to Perceptual Learning. First, perceptual learning cannot be studied on its own because it is closely linked to other aspects of cognition, such as attention, working memory, decision making, and conceptual knowledge. Second, perceptual learning is sensitive to both the stimulus properties of the environment in which an observer exists and to the properties of the tasks that the observer needs to perform. Moreover, the environmental and task properties can be characterized through their statistical regularities. Finally, the study of perceptual learning has important implications for society, including implications for science education and medical rehabilitation. Contributed articles relevant to each theme are summarized. Copyright © 2010 Cognitive Science Society, Inc.

Differential interference effects of negative emotional states on subsequent semantic and perceptual processing

PubMed Central

Gorlick, Marissa A.; Mather, Mara

2012-01-01

Past studies have revealed that encountering negative events interferes with cognitive processing of subsequent stimuli. The present study investigated whether negative events affect semantic and perceptual processing differently. Presentation of negative pictures produced slower reaction times than neutral or positive pictures in tasks that require semantic processing, such as natural/man-made judgments about drawings of objects, commonness judgments about objects, and categorical judgments about pairs of words. In contrast, negative picture presentation did not slow down judgments in subsequent perceptual processing (e.g., color judgments about words, and size judgments about objects). The subjective arousal level of negative pictures did not modulate the interference effects on semantic/perceptual processing. These findings indicate that encountering negative emotional events interferes with semantic processing of subsequent stimuli more strongly than perceptual processing, and that not all types of subsequent cognitive processing are impaired by negative events. PMID:22142207

Differential interference effects of negative emotional states on subsequent semantic and perceptual processing.

PubMed

Sakaki, Michiko; Gorlick, Marissa A; Mather, Mara

2011-12-01

Past studies have revealed that encountering negative events interferes with cognitive processing of subsequent stimuli. The present study investigates whether negative events affect semantic and perceptual processing differently. Presentation of negative pictures produced slower reaction times than neutral or positive pictures in tasks that require semantic processing, such as natural or man-made judgments about drawings of objects, commonness judgments about objects, and categorical judgments about pairs of words. In contrast, negative picture presentation did not slow down judgments in subsequent perceptual processing (e.g., color judgments about words, size judgments about objects). The subjective arousal level of negative pictures did not modulate the interference effects on semantic or perceptual processing. These findings indicate that encountering negative emotional events interferes with semantic processing of subsequent stimuli more strongly than perceptual processing, and that not all types of subsequent cognitive processing are impaired by negative events. (c) 2011 APA, all rights reserved.

Neurophysiological indices of perceptual object priming in the absence of explicit recognition memory.

PubMed

Harris, Jill D; Cutmore, Tim R H; O'Gorman, John; Finnigan, Simon; Shum, David

2009-02-01

The aim of this study was to identify ERP correlates of perceptual object priming that are insensitive to factors affecting explicit, episodic memory. EEG was recorded from 21 participants while they performed a visual object recognition test on a combination of unstudied items and old items that were previously encountered during either a 'deep' or 'shallow' levels-of-processing (LOP) study task. The results demonstrated a midline P150 old/new effect which was sensitive only to objects' old/new status and not to the accuracy of recognition responses to old items, or to the LOP manipulation. Similar outcomes were observed for the subsequent P200 and N400 effects, the former of which had a parietal scalp maximum and the latter, a broadly distributed topography. In addition an LPC old/new effect typical of those reported in past ERP recognition studies was observed. These outcomes support the proposal that the P150 effect is reflective of perceptual object priming and moreover, provide novel evidence that this and the P200 effect are independent of explicit recognition memory process(es).

Perceptual centres in speech - an acoustic analysis

NASA Astrophysics Data System (ADS)

Scott, Sophie Kerttu

Perceptual centres, or P-centres, represent the perceptual moments of occurrence of acoustic signals - the 'beat' of a sound. P-centres underlie the perception and production of rhythm in perceptually regular speech sequences. P-centres have been modelled both in speech and non speech (music) domains. The three aims of this thesis were toatest out current P-centre models to determine which best accounted for the experimental data bto identify a candidate parameter to map P-centres onto (a local approach) as opposed to the previous global models which rely upon the whole signal to determine the P-centre the final aim was to develop a model of P-centre location which could be applied to speech and non speech signals. The first aim was investigated by a series of experiments in which a) speech from different speakers was investigated to determine whether different models could account for variation between speakers b) whether rendering the amplitude time plot of a speech signal affects the P-centre of the signal c) whether increasing the amplitude at the offset of a speech signal alters P-centres in the production and perception of speech. The second aim was carried out by a) manipulating the rise time of different speech signals to determine whether the P-centre was affected, and whether the type of speech sound ramped affected the P-centre shift b) manipulating the rise time and decay time of a synthetic vowel to determine whether the onset alteration was had more affect on P-centre than the offset manipulation c) and whether the duration of a vowel affected the P-centre, if other attributes (amplitude, spectral contents) were held constant. The third aim - modelling P-centres - was based on these results. The Frequency dependent Amplitude Increase Model of P-centre location (FAIM) was developed using a modelling protocol, the APU GammaTone Filterbank and the speech from different speakers. The P-centres of the stimuli corpus were highly predicted by attributes of

The Sense of Being Watched Is Modulated by Arousal and Duration of the Perceptual Episode

PubMed Central

Carbon, Claus-Christian; Hecht, Heiko

2017-01-01

The mere presence of a depiction of eyes can elicit a sense of being watched in the perceiver. To this date, the factors affecting the intensity of this sense of being watched, however, have not been investigated. In the present experiment, we tested the impact of two potentially relevant variables: arousal (manipulated using specific musical pieces) and duration of the perceptual episode (manipulated using presentation times of 200 ms and 10 s, respectively). We asked participants to report how intensely they felt being watched while we exposed them to various observation cues ranging from human eyes to surveillance cameras. We found that, on average, reported intensities were higher if participants were in a state of relatively higher arousal and if the perceptual episode during which the respective observation cues were presented lasted long enough (10 s) to allow more than a first glance. Scientific and practical implications are briefly discussed. PMID:29230277

Source misattributions and false recognition errors: examining the role of perceptual resemblance and imagery generation processes.

PubMed

Foley, Mary Ann; Bays, Rebecca Brooke; Foy, Jeffrey; Woodfield, Mila

2015-01-01

In three experiments, we examine the extent to which participants' memory errors are affected by the perceptual features of an encoding series and imagery generation processes. Perceptual features were examined by manipulating the features associated with individual items as well as the relationships among items. An encoding instruction manipulation was included to examine the effects of explicit requests to generate images. In all three experiments, participants falsely claimed to have seen pictures of items presented as words, committing picture misattribution errors. These misattribution errors were exaggerated when the perceptual resemblance between pictures and images was relatively high (Experiment 1) and when explicit requests to generate images were omitted from encoding instructions (Experiments 1 and 2). When perceptual cues made the thematic relationships among items salient, the level and pattern of misattribution errors were also affected (Experiments 2 and 3). Results address alternative views about the nature of internal representations resulting in misattribution errors and refute the idea that these errors reflect only participants' general impressions or beliefs about what was seen.

Perceptual Learning: Use-Dependent Cortical Plasticity.

PubMed

Li, Wu

2016-10-14

Our perceptual abilities significantly improve with practice. This phenomenon, known as perceptual learning, offers an ideal window for understanding use-dependent changes in the adult brain. Different experimental approaches have revealed a diversity of behavioral and cortical changes associated with perceptual learning, and different interpretations have been given with respect to the cortical loci and neural processes responsible for the learning. Accumulated evidence has begun to put together a coherent picture of the neural substrates underlying perceptual learning. The emerging view is that perceptual learning results from a complex interplay between bottom-up and top-down processes, causing a global reorganization across cortical areas specialized for sensory processing, engaged in top-down attentional control, and involved in perceptual decision making. Future studies should focus on the interactions among cortical areas for a better understanding of the general rules and mechanisms underlying various forms of skill learning.

Influence of semantic consistency and perceptual features on visual attention during scene viewing in toddlers.

PubMed

Helo, Andrea; van Ommen, Sandrien; Pannasch, Sebastian; Danteny-Dordoigne, Lucile; Rämä, Pia

2017-11-01

Conceptual representations of everyday scenes are built in interaction with visual environment and these representations guide our visual attention. Perceptual features and object-scene semantic consistency have been found to attract our attention during scene exploration. The present study examined how visual attention in 24-month-old toddlers is attracted by semantic violations and how perceptual features (i. e. saliency, centre distance, clutter and object size) and linguistic properties (i. e. object label frequency and label length) affect gaze distribution. We compared eye movements of 24-month-old toddlers and adults while exploring everyday scenes which either contained an inconsistent (e.g., soap on a breakfast table) or consistent (e.g., soap in a bathroom) object. Perceptual features such as saliency, centre distance and clutter of the scene affected looking times in the toddler group during the whole viewing time whereas looking times in adults were affected only by centre distance during the early viewing time. Adults looked longer to inconsistent than consistent objects either if the objects had a high or a low saliency. In contrast, toddlers presented semantic consistency effect only when objects were highly salient. Additionally, toddlers with lower vocabulary skills looked longer to inconsistent objects while toddlers with higher vocabulary skills look equally long to both consistent and inconsistent objects. Our results indicate that 24-month-old children use scene context to guide visual attention when exploring the visual environment. However, perceptual features have a stronger influence in eye movement guidance in toddlers than in adults. Our results also indicate that language skills influence cognitive but not perceptual guidance of eye movements during scene perception in toddlers. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluative pressure overcomes perceptual load effects.

PubMed

Normand, Alice; Autin, Frédérique; Croizet, Jean-Claude

2015-06-01

Perceptual load has been found to be a powerful bottom-up determinant of distractibility, with high perceptual load preventing distraction by any irrelevant information. However, when under evaluative pressure, individuals exert top-down attentional control by giving greater weight to task-relevant features, making them more distractible from task-relevant distractors. One study tested whether the top-down modulation of attention under evaluative pressure overcomes the beneficial bottom-up effect of high perceptual load on distraction. Using a response-competition task, we replicated previous findings that high levels of perceptual load suppress task-relevant distractor response interference, but only for participants in a control condition. Participants under evaluative pressure (i.e., who believed their intelligence was assessed) showed interference from task-relevant distractor at all levels of perceptual load. This research challenges the assumptions of the perceptual load theory and sheds light on a neglected determinant of distractibility: the self-relevance of the performance situation in which attentional control is solicited.

Perceptual conflict during sensorimotor integration processes - a neurophysiological study in response inhibition.

PubMed

Chmielewski, Witold X; Beste, Christian

2016-05-25

A multitude of sensory inputs needs to be processed during sensorimotor integration. A crucial factor for detecting relevant information is its complexity, since information content can be conflicting at a perceptual level. This may be central to executive control processes, such as response inhibition. This EEG study aims to investigate the system neurophysiological mechanisms behind effects of perceptual conflict on response inhibition. We systematically modulated perceptual conflict by integrating a Global-local task with a Go/Nogo paradigm. The results show that conflicting perceptual information, in comparison to non-conflicting perceptual information, impairs response inhibition performance. This effect was evident regardless of whether the relevant information for response inhibition is displayed on the global, or local perceptual level. The neurophysiological data suggests that early perceptual/ attentional processing stages do not underlie these modulations. Rather, processes at the response selection level (P3), play a role in changed response inhibition performance. This conflict-related impairment of inhibitory processes is associated with activation differences in (inferior) parietal areas (BA7 and BA40) and not as commonly found in the medial prefrontal areas. This suggests that various functional neuroanatomical structures may mediate response inhibition and that the functional neuroanatomical structures involved depend on the complexity of sensory integration processes.

Task-relevant perceptual features can define categories in visual memory too.

PubMed

Antonelli, Karla B; Williams, Carrick C

2017-11-01

Although Konkle, Brady, Alvarez, and Oliva (2010, Journal of Experimental Psychology: General, 139(3), 558) claim that visual long-term memory (VLTM) is organized on underlying conceptual, not perceptual, information, visual memory results from visual search tasks are not well explained by this theory. We hypothesized that when viewing an object, any task-relevant visual information is critical to the organizational structure of VLTM. In two experiments, we examined the organization of VLTM by measuring the amount of retroactive interference created by objects possessing different combinations of task-relevant features. Based on task instructions, only the conceptual category was task relevant or both the conceptual category and a perceptual object feature were task relevant. Findings indicated that when made task relevant, perceptual object feature information, along with conceptual category information, could affect memory organization for objects in VLTM. However, when perceptual object feature information was task irrelevant, it did not contribute to memory organization; instead, memory defaulted to being organized around conceptual category information. These findings support the theory that a task-defined organizational structure is created in VLTM based on the relevance of particular object features and information.

Temporally selective attention modulates early perceptual processing: event-related potential evidence.

PubMed

Sanders, Lisa D; Astheimer, Lori B

2008-05-01

Some of the most important information we encounter changes so rapidly that our perceptual systems cannot process all of it in detail. Spatially selective attention is critical for perception when more information than can be processed in detail is presented simultaneously at distinct locations. When presented with complex, rapidly changing information, listeners may need to selectively attend to specific times rather than to locations. We present evidence that listeners can direct selective attention to time points that differ by as little as 500 msec, and that doing so improves target detection, affects baseline neural activity preceding stimulus presentation, and modulates auditory evoked potentials at a perceptually early stage. These data demonstrate that attentional modulation of early perceptual processing is temporally precise and that listeners can flexibly allocate temporally selective attention over short intervals, making it a viable mechanism for preferentially processing the most relevant segments in rapidly changing streams.

Examining Chemistry Students Visual-Perceptual Skills Using the VSCS tool and Interview Data

NASA Astrophysics Data System (ADS)

Christian, Caroline

The Visual-Spatial Chemistry Specific (VSCS) assessment tool was developed to test students' visual-perceptual skills, which are required to form a mental image of an object. The VSCS was designed around the theoretical framework of Rochford and Archer that provides eight distinct and well-defined visual-perceptual skills with identified problems students might have with each skill set. Factor analysis was used to analyze the results during the validation process of the VSCS. Results showed that the eight factors could not be separated from each other, but instead two factors emerged as significant to the data. These two factors have been defined and described as a general visual-perceptual skill (factor 1) and a skill that adds on a second level of complexity by involving multiple viewpoints such as changing frames of reference. The questions included in the factor analysis were bolstered by the addition of an item response theory (IRT) analysis. Interviews were also conducted with twenty novice students to test face validity of the tool, and to document student approaches at solving visualization problems of this type. Students used five main physical resources or processes to solve the questions, but the resource that was the most successful was handling or building a physical representation of an object.

Conflict-Induced Perceptual Filtering

ERIC Educational Resources Information Center

Wendt, Mike; Luna-Rodriguez, Aquiles; Jacobsen, Thomas

2012-01-01

In a variety of conflict paradigms, target and distractor stimuli are defined in terms of perceptual features. Interference evoked by distractor stimuli tends to be reduced when the ratio of congruent to incongruent trials is decreased, suggesting conflict-induced perceptual filtering (i.e., adjusting the processing weights assigned to stimuli…

Effects of working memory contents and perceptual load on distractor processing: When a response-related distractor is held in working memory.

PubMed

Koshino, Hideya

2017-01-01

Working memory and attention are closely related. Recent research has shown that working memory can be viewed as internally directed attention. Working memory can affect attention in at least two ways. One is the effect of working memory load on attention, and the other is the effect of working memory contents on attention. In the present study, an interaction between working memory contents and perceptual load in distractor processing was investigated. Participants performed a perceptual load task in a standard form in one condition (Single task). In the other condition, a response-related distractor was maintained in working memory, rather than presented in the same stimulus display as a target (Dual task). For the Dual task condition, a significant compatibility effect was found under high perceptual load; however, there was no compatibility effect under low perceptual load. These results suggest that the way the contents of working memory affect visual search depends on perceptual load. Copyright © 2016 Elsevier B.V. All rights reserved.

Perceptual impressions of causality are affected by common fate.

PubMed

White, Peter A

2017-03-24

Many studies of perceptual impressions of causality have used a stimulus in which a moving object (the launcher) contacts a stationary object (the target) and the latter then moves off. Such stimuli give rise to an impression that the launcher makes the target move. In the present experiments, instead of a single target object, an array of four vertically aligned objects was used. The launcher contacted none of them, but stopped at a point between the two central objects. The four objects then moved with similar motion properties, exhibiting the Gestalt property of common fate. Strong impressions of causality were reported for this stimulus. It is argued that the array of four objects was perceived, by the likelihood principle, as a single object with some parts unseen, that the launcher was perceived as contacting one of the unseen parts of this object, and that the causal impression resulted from that. Supporting that argument, stimuli in which kinematic features were manipulated so as to weaken or eliminate common fate yielded weaker impressions of causality.

Domain-specific perceptual causality in children depends on the spatio-temporal configuration, not motion onset

PubMed Central

Schlottmann, Anne; Cole, Katy; Watts, Rhianna; White, Marina

2013-01-01

Humans, even babies, perceive causality when one shape moves briefly and linearly after another. Motion timing is crucial in this and causal impressions disappear with short delays between motions. However, the role of temporal information is more complex: it is both a cue to causality and a factor that constrains processing. It affects ability to distinguish causality from non-causality, and social from mechanical causality. Here we study both issues with 3- to 7-year-olds and adults who saw two computer-animated squares and chose if a picture of mechanical, social or non-causality fit each event best. Prior work fit with the standard view that early in development, the distinction between the social and physical domains depends mainly on whether or not the agents make contact, and that this reflects concern with domain-specific motion onset, in particular, whether the motion is self-initiated or not. The present experiments challenge both parts of this position. In Experiments 1 and 2, we showed that not just spatial, but also animacy and temporal information affect how children distinguish between physical and social causality. In Experiments 3 and 4 we showed that children do not seem to use spatio-temporal information in perceptual causality to make inferences about self- or other-initiated motion onset. Overall, spatial contact may be developmentally primary in domain-specific perceptual causality in that it is processed easily and is dominant over competing cues, but it is not the only cue used early on and it is not used to infer motion onset. Instead, domain-specific causal impressions may be automatic reactions to specific perceptual configurations, with a complex role for temporal information. PMID:23874308

The importance of perceptual experience in the esthetic appreciation of the body.

PubMed

Mele, Sonia; Cazzato, Valentina; Urgesi, Cosimo

2013-01-01

Several studies suggest that sociocultural models conveying extreme thinness as the widespread ideal of beauty exert an important influence on the perceptual and emotional representation of body image. The psychological mechanisms underlying such environmental influences, however, are unclear. Here, we utilized a perceptual adaptation paradigm to investigate how perceptual experience modulates body esthetic appreciation. We found that the liking judgments of round bodies increased or decreased after brief exposure to round or thin bodies, respectively. No change occurred in the liking judgments of thin bodies. The results suggest that perceptual experience may shape our esthetic appreciation to favor more familiar round body figures. Importantly, individuals with more deficits in interoceptive awareness were less prone to increase their liking ratings of round bodies after exposure, suggesting a specific risk factor for the susceptibility to the influence of the extreme thin vs. round body ideals of beauty portrayed by the media.

The Importance of Perceptual Experience in the Esthetic Appreciation of the Body

PubMed Central

Mele, Sonia; Cazzato, Valentina; Urgesi, Cosimo

2013-01-01

Several studies suggest that sociocultural models conveying extreme thinness as the widespread ideal of beauty exert an important influence on the perceptual and emotional representation of body image. The psychological mechanisms underlying such environmental influences, however, are unclear. Here, we utilized a perceptual adaptation paradigm to investigate how perceptual experience modulates body esthetic appreciation. We found that the liking judgments of round bodies increased or decreased after brief exposure to round or thin bodies, respectively. No change occurred in the liking judgments of thin bodies. The results suggest that perceptual experience may shape our esthetic appreciation to favor more familiar round body figures. Importantly, individuals with more deficits in interoceptive awareness were less prone to increase their liking ratings of round bodies after exposure, suggesting a specific risk factor for the susceptibility to the influence of the extreme thin vs. round body ideals of beauty portrayed by the media. PMID:24324689

Characterizing Perceptual Learning with External Noise

ERIC Educational Resources Information Center

Gold, Jason M.; Sekuler, Allison B.; Bennett, Partrick J.

2004-01-01

Performance in perceptual tasks often improves with practice. This effect is known as "perceptual learning," and it has been the source of a great deal of interest and debate over the course of the last century. Here, we consider the effects of perceptual learning within the context of signal detection theory. According to signal detection theory,…

Factors affecting sign retroreflectivity

DOT National Transportation Integrated Search

2001-01-01

This study was undertaken to better understand the factors that may affect road sign retroreflectivity, specifically age and physical orientation. A better understanding of these factors could provide guidance to ODOT in managing its inventory of roa...

The Attentional Drift Diffusion Model of Simple Perceptual Decision-Making.

PubMed

Tavares, Gabriela; Perona, Pietro; Rangel, Antonio

2017-01-01

Perceptual decisions requiring the comparison of spatially distributed stimuli that are fixated sequentially might be influenced by fluctuations in visual attention. We used two psychophysical tasks with human subjects to investigate the extent to which visual attention influences simple perceptual choices, and to test the extent to which the attentional Drift Diffusion Model (aDDM) provides a good computational description of how attention affects the underlying decision processes. We find evidence for sizable attentional choice biases and that the aDDM provides a reasonable quantitative description of the relationship between fluctuations in visual attention, choices and reaction times. We also find that exogenous manipulations of attention induce choice biases consistent with the predictions of the model.

Perceptual load, voluntary attention, and aging: an event-related potential study

PubMed Central

Wang, Yan; Fu, Shimin; Greenwood, Pamela; Luo, Yuejia; Parasuraman, Raja

2012-01-01

The locus of attentional selection is known to vary with perceptual load (Lavie et al., 2004). Under voluntary attention, perceptual load modulates selective visual processing at an early cortical stage, as reflected in the posterior P1 and N1 components of the event-related potentials (ERPs). Adult aging also affects both behavioral and ERP signs of attentional selection. However, it is not known whether perceptual load modulates this relationship. Accordingly, in the present study ERPs were recorded in a voluntary attention task. Young and old participants were asked to discriminate the direction of a target line embedded within a display of four lines that appeared in the left or right visual field. Participants responded faster and more accurately to valid relative to invalid trials and to low-load relative to high-load condition. Older participants responded more slowly and with lower accuracy than young participants in all conditions. The amplitudes of the posterior contralateral P1 and N1 components in valid trials were larger than that in invalid trials in all conditions. N1 amplitude was larger under the high load condition than that in the low load condition. Moreover, in the high perceptual load condition, the old group had a larger N1 than the young group at contralateral sites. The findings suggest that under voluntary attention, perceptual load and aging modulates attentional selection at an early but not the earliest stage, during the N1 (120–200ms) time range. Increased N1 amplitude in older adults may reflect increased demands on target discrimination in high perceptual load. PMID:22248536

The stress hormone cortisol blocks perceptual learning in humans.

PubMed

Dinse, Hubert R; Kattenstroth, J C; Lenz, M; Tegenthoff, M; Wolf, O T

2017-03-01

Cortisol, the primary glucocorticoid (GC) in humans, influences neuronal excitability and plasticity by acting on mineralocorticoid and glucocorticoid receptors. Cellular studies demonstrated that elevated GC levels affect neuronal plasticity, for example through a reduction of hippocampal long-term potentiation (LTP). At the behavioural level, after treatment with GCs, numerous studies have reported impaired hippocampal function, such as impaired memory retrieval. In contrast, relatively little is known about the impact of GCs on cortical plasticity and perceptual learning in adult humans. Therefore, in this study, we explored the impact of elevated GC levels on human perceptual learning. To this aim, we used a training-independent learning approach, where lasting changes in human perception can be induced by applying passive repetitive sensory stimulation (rss), the timing of which was determined from cellular LTP studies. In our placebo-controlled double-blind study, we used tactile LTP-like stimulation to induce improvements in tactile acuity (spatial two-point discrimination). Our results show that a single administration of hydrocortisone (30mg) completely blocked rss-induced changes in two-point discrimination. In contrast, the placebo group showed the expected rss-induced increase in two-point discrimination of over 14%. Our data demonstrate that high GC levels inhibit rss-induced perceptual learning. We suggest that the suppression of LTP, as previously reported in cellular studies, may explain the perceptual learning impairments observed here. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

The Efficacy of Auditory Perceptual Training for Tinnitus: A Systematic Review

PubMed Central

Stacey, Paula C.; Hall, Deborah A.

2010-01-01

Auditory perceptual training affects neural plasticity and so represents a potential strategy for tinnitus management. We assessed the effects of auditory perceptual training on tinnitus perception and/or its intrusiveness via a systematic review of published literature. An electronic database search using the keywords ‘tinnitus and learning’ or ‘tinnitus and training’ was conducted, updated by a hand search. The ten studies identified were reviewed independently by two reviewers, data were extracted, study quality was assessed according to a number of specific criteria and the information was synthesised using a narrative approach. Nine out of the ten studies reported some significant change in either self-reported or psychoacoustic outcome measures after auditory training. However, all studies were quality rated as providing low or moderate levels of evidence for an effect. We identify a need for appropriately randomised and controlled studies that will generate high-quality unbiased and generalisable evidence to ascertain whether or not auditory perceptual training has a clinically relevant effect on tinnitus. PMID:20668974

Perceptual advantage for category-relevant perceptual dimensions: the case of shape and motion.

PubMed

Folstein, Jonathan R; Palmeri, Thomas J; Gauthier, Isabel

2014-01-01

Category learning facilitates perception along relevant stimulus dimensions, even when tested in a discrimination task that does not require categorization. While this general phenomenon has been demonstrated previously, perceptual facilitation along dimensions has been documented by measuring different specific phenomena in different studies using different kinds of objects. Across several object domains, there is support for acquired distinctiveness, the stretching of a perceptual dimension relevant to learned categories. Studies using faces and studies using simple separable visual dimensions have also found evidence of acquired equivalence, the shrinking of a perceptual dimension irrelevant to learned categories, and categorical perception, the local stretching across the category boundary. These later two effects are rarely observed with complex non-face objects. Failures to find these effects with complex non-face objects may have been because the dimensions tested previously were perceptually integrated. Here we tested effects of category learning with non-face objects categorized along dimensions that have been found to be processed by different areas of the brain, shape and motion. While we replicated acquired distinctiveness, we found no evidence for acquired equivalence or categorical perception.

Perceptual and cognitive biases in individuals with body dysmorphic disorder symptoms.

PubMed

Clerkin, Elise M; Teachman, Bethany A

2008-01-01

Given the extreme focus on perceived physical defects in body dysmorphic disorder (BDD), we expected that perceptual and cognitive biases related to physical appearance would be associated with BDD symptomology. To examine these hypotheses, participants ( N = 70) high and low in BDD symptoms completed tasks assessing visual perception and cognition. As expected, there were significant group differences in self-, but not other-, relevant cognitive biases. Perceptual bias results were mixed, with some evidence indicating that individuals high (versus low) in BDD symptoms literally see themselves in a less positive light. Further, individuals high in BDD symptoms failed to demonstrate a normative self-enhancement bias. Overall, this research points to the importance of assessing both cognitive and perceptual biases associated with BDD symptoms, and suggests that visual perception may be influenced by non-visual factors.

Acute Stress and Perceptual Load Consume the Same Attentional Resources: A Behavioral-ERP Study

PubMed Central

Tiferet-Dweck, Chen; Hensel, Michael; Kirschbaum, Clemens; Tzelgov, Joseph; Friedman, Alon; Salti, Moti

2016-01-01

Stress and perceptual load affect selective attention in a paradoxical manner. They can facilitate selectivity or disrupt it. This EEG study was designed to examine the reciprocal relations between stress, load and attention. Two groups of subjects, one that performed the Trier Social Stress Test (TSST), and a control group, were asked to respond to a target letter under low and high perceptual load in the absence or presence of a distractor. In the control group, the distractor increased response times (RTs) for high and low load. In the TSST group, distractor increased RTs under low load only. ERPs showed that distractor’s presentation attenuated early visual P1 component and shortened its latency. In the TSST group, distractor reduced P1 component under high load but did not affect its latency. Source localization demonstrated reduced activation in V1 in response to distractors presence in the P1 time window for the TSST group compared to the control group. A behavioral replication revealed that in the TSST group distractors were less perceived under high load. Taken together, our results show that stress and perceptual load affect selectivity through the early stages of visual processing and might increase selectivity in a manner that would block conscious perception of irrelevant stimuli. PMID:27196027

Perceptual issues in scientific visualization

NASA Technical Reports Server (NTRS)

Kaiser, Mary K.; Proffitt, Dennis R.

1989-01-01

In order to develop effective tools for scientific visulaization, consideration must be given to the perceptual competencies, limitations, and biases of the human operator. Perceptual psychology has amassed a rich body of research on these issues and can lend insight to the development of visualization tehcniques. Within a perceptual psychological framework, the computer display screen can best be thought of as a special kind of impoverished visual environemnt. Guidelines can be gleaned from the psychological literature to help visualization tool designers avoid ambiguities and/or illusions in the resulting data displays.

A study of perceptual and verbal skills of disabled readers in grades 4, 5 and 6.

PubMed

Solan, H A; Ficarra, A P

1990-08-01

This investigation addresses the role of the optometrist in diagnosing and treating children in grades 4, 5, and 6 who have been identified as reading disabled. Fifty-one subjects with average intelligence, but whose reading comprehension skills were below the 31st percentile (mean, 20th percentile), were evaluated using verbal and perceptual tests. When the performance of this experimental group was compared with the mean scores from standardized test norms for each of the various tasks, the disabled readers scored significantly lower in seven of the eight perceptual and five of the six verbal tasks. These results lend support to the hypothesis that both perceptual and verbal deficits are related to reading comprehension. Using step-wise multiple correlation analysis, three perceptual factors; eye-movements, Auditory-Visual Integration Test (AVIT), and grooved peg-board, contributed 38 percent of the variance whereas the addition of two verbal factors (digit span and token test) provided just 2 percent. That is, 38 percent of the variations in reading comprehension could be accounted for by variations in perceptual skills in the disabled readers. The results were interpreted in terms of spatial-simultaneous and verbal-successive processing skills.

Speech Synthesis Using Perceptually Motivated Features

DTIC Science & Technology

2012-01-23

with others a few years prior (with the concurrence of the project’s program manager. Willard Larkin). The Perceptual Flow of Phonetic Information and...34The Perceptual Flow of Phonetic Processing," consonant confusion matrices are analyzed for patterns of phonetic-feature decoding errors conditioned...decoding) is also observed. From these conditional probability patterns, it is proposed that they reflect a temporal flow of perceptual processing

The effects of malnutrition on the motor, perceptual, and cognitive functions of Filipino children.

PubMed

Reyes, M R; Valdecanas, C M; Reyes, O L; Reyes, T M

1990-01-01

The motor, perceptual, and cognitive abilities of 99 Filipino children, aged 4-6 years with a documented history of malnutrition from a nutritionally depressed area of Manila were determined using the Revised Manila Motor-Perceptual Screening Test. They were classified into four groups of: (1) normal; (2) acutely malnourished; (3) stunted but not malnourished; and (4) chronically malnourished using the Waterlow classification. Thirty-one normal children of comparable ages and background from a nationwide pool were similarly tested and served as the control group. Motor (p = 0.001) and perceptual skill (p less than 0.03 to less than 0.001) scores were significantly lower than in their normal counterparts, especially in the chronically malnourished children. Cognitive abilities were not evidently affected by malnutrition.

Generation and Perceptual Implicit Memory: Different Generation Tasks Produce Different Effects on Perceptual Priming

ERIC Educational Resources Information Center

Mulligan, Neil W.; Dew, Ilana T. Z.

2009-01-01

The generation manipulation has been critical in delineating differences between implicit and explicit memory. In contrast to past research, the present experiments indicate that generating from a rhyme cue produces as much perceptual priming as does reading. This is demonstrated for 3 visual priming tasks: perceptual identification, word-fragment…

Opposite Influence of Perceptual Memory on Initial and Prolonged Perception of Sensory Ambiguity

PubMed Central

de Jong, Maartje Cathelijne; Knapen, Tomas; van Ee, Raymond

2012-01-01

Observers continually make unconscious inferences about the state of the world based on ambiguous sensory information. This process of perceptual decision-making may be optimized by learning from experience. We investigated the influence of previous perceptual experience on the interpretation of ambiguous visual information. Observers were pre-exposed to a perceptually stabilized sequence of an ambiguous structure-from-motion stimulus by means of intermittent presentation. At the subsequent re-appearance of the same ambiguous stimulus perception was initially biased toward the previously stabilized perceptual interpretation. However, prolonged viewing revealed a bias toward the alternative perceptual interpretation. The prevalence of the alternative percept during ongoing viewing was largely due to increased durations of this percept, as there was no reliable decrease in the durations of the pre-exposed percept. Moreover, the duration of the alternative percept was modulated by the specific characteristics of the pre-exposure, whereas the durations of the pre-exposed percept were not. The increase in duration of the alternative percept was larger when the pre-exposure had lasted longer and was larger after ambiguous pre-exposure than after unambiguous pre-exposure. Using a binocular rivalry stimulus we found analogous perceptual biases, while pre-exposure did not affect eye-bias. We conclude that previously perceived interpretations dominate at the onset of ambiguous sensory information, whereas alternative interpretations dominate prolonged viewing. Thus, at first instance ambiguous information seems to be judged using familiar percepts, while re-evaluation later on allows for alternative interpretations. PMID:22295095

Combining perceptual regulation and exergaming for exercise prescription in low-active adults with and without cognitive impairment.

PubMed

McAuliffe, Liam; Parfitt, Gaynor C; Eston, Roger G; Gray, Caitlin; Keage, Hannah A D; Smith, Ashleigh E

2018-01-01

Exercise adherence in already low-active older adults with and without mild cognitive impairment (MCI) remains low. Perceptual regulation and exergaming may facilitate future exercise behaviour by improving the affective experience, however evidence that this population can perceptually regulate is lacking. To explore this, we investigated 1) perceptual regulation of exercise intensity during either exergaming or regular ergometer cycling and 2) explored affective responses. Thirty-two low active older adults (73.9 ± 7.3 years, n  = 16, 8 females) with or without MCI (70.9 ± 5.5 years, n  = 16, 11 females) participated in a sub-maximal fitness assessment to determine ventilatory threshold (VT) and two experimental sessions (counterbalanced: exergaming or regular ergometer cycling). Experimental sessions consisted 21-min of continuous cycling with 7-min at each: RPE 9, 11 and 13. Oxygen consumption (VO 2 ), heart rate (HR), and affect (Feeling Scale) were obtained throughout the exercise. VO 2 ( p  < 0.01) and HR ( p  < 0.01) increased linearly with RPE, but were not significantly different between exercise modes or cognitive groups. At RPE 13, participants worked above VT in both modes (exergaming: 115.7 ± 27.3; non-exergaming 114.1 ± 24.3 VO 2 (%VT)). Regardless of cognitive group, affect declined significantly as RPE increased ( p  < 0.01). However on average, affect remained pleasant throughout and did not differ between exercise modes or cognitive groups. These results suggest low-active older adults can perceptually regulate exercise intensity, regardless of cognition or mode. At RPE 13, participants regulated above VT, at an intensity that improves cardiorespiratory fitness long-term, and affect remained positive in the majority of participants, which may support long-term physical activity adherence.

Effects of linguistic experience on early levels of perceptual tone processing

NASA Astrophysics Data System (ADS)

Huang, Tsan; Johnson, Keith

2005-04-01

This study investigated the phenomenon of language-specificity in Mandarin Chinese tone perception. The main question was whether linguistic experience affects the earliest levels of perceptual processing of tones. Chinese and American English listeners participated in four perception experiments, which involved short inter-stimulus intervals (300 ms or 100 ms) and an AX discrimination or AX degree-of-difference rating task. Three experiments used natural speech monosyllabic tone stimuli and one experiment used time-varying sinusoidal simulations of Mandarin tones. AE listeners showed psychoacoustic listening in all experiments, paying much attention to onset and offset pitch. Chinese listeners showed language-specific patterns in all experiments to various degrees, where tonal neutralization rules reduced perceptual distance between two otherwise contrastive tones for Chinese listeners. Since these experiments employed procedures hypothesized to tap the auditory trace mode (Pisoni, Percept. Psychophys. 13, 253-260 (1973)], language-specificity found in this study seems to support the proposal of an auditory cortical map [Guenther et al., J. Acoust. Soc. Am. 23, 213-221 (1999)]. But the model needs refining to account for different degrees of language-specificity, which are better handled by Johnsons (2004, TLS03:26-41) lexical distance model, although the latter model is too rigid in assuming that linguistic experience does not affect low-level perceptual tasks such as AX discrimination with short ISIs.

Spatiotemporal dynamics of random stimuli account for trial-to-trial variability in perceptual decision making

PubMed Central

Park, Hame; Lueckmann, Jan-Matthis; von Kriegstein, Katharina; Bitzer, Sebastian; Kiebel, Stefan J.

2016-01-01

Decisions in everyday life are prone to error. Standard models typically assume that errors during perceptual decisions are due to noise. However, it is unclear how noise in the sensory input affects the decision. Here we show that there are experimental tasks for which one can analyse the exact spatio-temporal details of a dynamic sensory noise and better understand variability in human perceptual decisions. Using a new experimental visual tracking task and a novel Bayesian decision making model, we found that the spatio-temporal noise fluctuations in the input of single trials explain a significant part of the observed responses. Our results show that modelling the precise internal representations of human participants helps predict when perceptual decisions go wrong. Furthermore, by modelling precisely the stimuli at the single-trial level, we were able to identify the underlying mechanism of perceptual decision making in more detail than standard models. PMID:26752272

Perceptual integration without conscious access

PubMed Central

van Leeuwen, Jonathan; Olivers, Christian N. L.

2017-01-01

The visual system has the remarkable ability to integrate fragmentary visual input into a perceptually organized collection of surfaces and objects, a process we refer to as perceptual integration. Despite a long tradition of perception research, it is not known whether access to consciousness is required to complete perceptual integration. To investigate this question, we manipulated access to consciousness using the attentional blink. We show that, behaviorally, the attentional blink impairs conscious decisions about the presence of integrated surface structure from fragmented input. However, despite conscious access being impaired, the ability to decode the presence of integrated percepts remains intact, as shown through multivariate classification analyses of electroencephalogram (EEG) data. In contrast, when disrupting perception through masking, decisions about integrated percepts and decoding of integrated percepts are impaired in tandem, while leaving feedforward representations intact. Together, these data show that access consciousness and perceptual integration can be dissociated. PMID:28325878

Perceptual Calibration for Immersive Display Environments

PubMed Central

Ponto, Kevin; Gleicher, Michael; Radwin, Robert G.; Shin, Hyun Joon

2013-01-01

The perception of objects, depth, and distance has been repeatedly shown to be divergent between virtual and physical environments. We hypothesize that many of these discrepancies stem from incorrect geometric viewing parameters, specifically that physical measurements of eye position are insufficiently precise to provide proper viewing parameters. In this paper, we introduce a perceptual calibration procedure derived from geometric models. While most research has used geometric models to predict perceptual errors, we instead use these models inversely to determine perceptually correct viewing parameters. We study the advantages of these new psychophysically determined viewing parameters compared to the commonly used measured viewing parameters in an experiment with 20 subjects. The perceptually calibrated viewing parameters for the subjects generally produced new virtual eye positions that were wider and deeper than standard practices would estimate. Our study shows that perceptually calibrated viewing parameters can significantly improve depth acuity, distance estimation, and the perception of shape. PMID:23428454

Seeing the world in black and white: the effects of perceptually induced mind-sets on judgment.

PubMed

Sleeth-Keppler, David

2007-09-01

Three experiments examined the notion that rudimentary perceptual experiences can serve as powerful guides to judgments under uncertainty. The results show that exposure to certain perceptual contrast patterns can influence the direction of bias without conscious awareness. In Experiment 1a, perception of alternating black and white squares, which served as orientation markers in a lexical decision task, resulted in a reduction of the well-known anchoring bias. Similar results were obtained when alternating high- and low-pitch tones were the orientation markers (Experiment 1b). Results of a final experiment provide evidence that perceptual contrast experiences can affect judgment-relevant representations across modalities.

Perception is key? Does perceptual sensitivity and parenting behavior predict children's reactivity to others' emotions?

PubMed

Weeland, Joyce; Van den Akker, Alithe; Slagt, Meike; Putnam, Samuel

2017-11-01

When interacting with other people, both children's biological predispositions and past experiences play a role in how they will process and respond to social-emotional cues. Children may partly differ in their reactions to such cues because they differ in the threshold for perceiving such cues in general. Theoretically, perceptual sensitivity (i.e., the amount of detection of slight, low-intensity stimuli from the external environment independent of visual and auditory ability) might, therefore, provide us with specific information on individual differences in susceptibility to the environment. However, the temperament trait of perceptual sensitivity is highly understudied. In an experiment, we tested whether school-aged children's (N=521, 52.5% boys, M age =9.72years, SD=1.51) motor (facial electromyography) and affective (self-report) reactivities to dynamic facial expressions and vocalizations is predicted by their (parent-reported) perceptual sensitivity. Our results indicate that children's perceptual sensitivity predicts their motor reactivity to both happy and angry expressions and vocalizations. In addition, perceptual sensitivity interacted with positive (but not negative) parenting behavior in predicting children's motor reactivity to these emotions. Our findings suggest that perceptual sensitivity might indeed provide us with information on individual differences in reactivity to social-emotional cues, both alone and in interaction with parenting behavior. Because perceptual sensitivity focuses specifically on whether children perceive cues from their environment, and not on whether these cues cause arousal and/or whether children are able to regulate this arousal, it should be considered that perceptual sensitivity lies at the root of such individual differences. Copyright © 2017 Elsevier Inc. All rights reserved.

On the joys of perceiving: Affect as feedback for perceptual predictions.

PubMed

Chetverikov, Andrey; Kristjánsson, Árni

2016-09-01

How we perceive, attend to, or remember the stimuli in our environment depends on our preferences for them. Here we argue that this dependence is reciprocal: pleasures and displeasures are heavily dependent on cognitive processing, namely, on our ability to predict the world correctly. We propose that prediction errors, inversely weighted with prior probabilities of predictions, yield subjective experiences of positive or negative affect. In this way, we link affect to predictions within a predictive coding framework. We discuss how three key factors - uncertainty, expectations, and conflict - influence prediction accuracy and show how they shape our affective response. We demonstrate that predictable stimuli are, in general, preferred to unpredictable ones, though too much predictability may decrease this liking effect. Furthermore, the account successfully overcomes the "dark-room" problem, explaining why we do not avoid stimulation to minimize prediction error. We further discuss the implications of our approach for art perception and the utility of affect as feedback for predictions within a prediction-testing architecture of cognition. Copyright © 2016 Elsevier B.V. All rights reserved.

Perceptual and cognitive biases in individuals with body dysmorphic disorder symptoms

PubMed Central

Clerkin, Elise M.; Teachman, Bethany A.

2012-01-01

Given the extreme focus on perceived physical defects in body dysmorphic disorder (BDD), we expected that perceptual and cognitive biases related to physical appearance would be associated with BDD symptomology. To examine these hypotheses, participants (N = 70) high and low in BDD symptoms completed tasks assessing visual perception and cognition. As expected, there were significant group differences in self-, but not other-, relevant cognitive biases. Perceptual bias results were mixed, with some evidence indicating that individuals high (versus low) in BDD symptoms literally see themselves in a less positive light. Further, individuals high in BDD symptoms failed to demonstrate a normative self-enhancement bias. Overall, this research points to the importance of assessing both cognitive and perceptual biases associated with BDD symptoms, and suggests that visual perception may be influenced by non-visual factors. PMID:25125771

Optimizing Linked Perceptual Class Formation and Transfer of Function

ERIC Educational Resources Information Center

Fields, Lanny; Garruto, Michelle

2009-01-01

A linked perceptual class consists of two distinct perceptual classes, A' and B', the members of which have become related to each other. For example, a linked perceptual class might be composed of many pictures of a woman (one perceptual class) and the sounds of that woman's voice (the other perceptual class). In this case, any sound of the…

Factors affecting construction performance: exploratory factor analysis

NASA Astrophysics Data System (ADS)

Soewin, E.; Chinda, T.

2018-04-01

The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

Neurally Constrained Modeling of Perceptual Decision Making

ERIC Educational Resources Information Center

Purcell, Braden A.; Heitz, Richard P.; Cohen, Jeremiah Y.; Schall, Jeffrey D.; Logan, Gordon D.; Palmeri, Thomas J.

2010-01-01

Stochastic accumulator models account for response time in perceptual decision-making tasks by assuming that perceptual evidence accumulates to a threshold. The present investigation mapped the firing rate of frontal eye field (FEF) visual neurons onto perceptual evidence and the firing rate of FEF movement neurons onto evidence accumulation to…

Perceptual belongingness determines the direction of lightness induction depending on grouping stability and intentionality.

PubMed

Murgia, Mauro; Prpic, Valter; Santoro, Ilaria; Sors, Fabrizio; Agostini, Tiziano; Galmonte, Alessandra

2016-09-01

Contrast and assimilation are two opposite perceptual phenomena deriving from the relationships among perceptual elements in a visual field. In contrast, perceptual differences are enhanced; while, in assimilation, they are decreased. Indeed, if contrast or assimilation occurs depends on various factors. Interestingly, Gestalt scientists explained both phenomena as the result of perceptual belongingness, giving rise to an intriguing paradox. Benary suggested that belongingness determines contrast; conversely, Fuchs suggested that it determines assimilation. This paradox can be related both to the grouping stability (stable/multi-stable) and to the grouping intentionality (intentional/non-intentional). In the present work we ran four experiments to test whether the contrast/assimilation outcomes depend on the above-mentioned variables. We found that, intentionality and multi-stability elicit assimilation; while, non-intentionality and stability elicit contrast. Copyright © 2016 Elsevier Ltd. All rights reserved.

The perceptual saliency of fearful eyes and smiles: A signal detection study

PubMed Central

Saban, Muhammet Ikbal; Rotshtein, Pia

2017-01-01

Facial features differ in the amount of expressive information they convey. Specifically, eyes are argued to be essential for fear recognition, while smiles are crucial for recognising happy expressions. In three experiments, we tested whether expression modulates the perceptual saliency of diagnostic facial features and whether the feature’s saliency depends on the face configuration. Participants were presented with masked facial features or noise at perceptual conscious threshold. The task was to indicate whether eyes (experiments 1-3A) or a mouth (experiment 3B) was present. The expression of the face and its configuration (i.e. spatial arrangement of the features) were manipulated. Experiment 1 compared fearful with neutral expressions, experiments 2 and 3 compared fearful versus happy expressions. The detection accuracy data was analysed using Signal Detection Theory (SDT), to examine the effects of expression and configuration on perceptual precision (d’) and response bias (c), separately. Across all three experiments, fearful eyes were detected better (higher d’) than neutral and happy eyes. Eyes were more precisely detected than mouths, whereas smiles were detected better than fearful mouths. The configuration of the features had no consistent effects across the experiments on the ability to detect expressive features. But facial configuration affected consistently the response bias. Participants used a more liberal criterion for detecting the eyes in canonical configuration and fearful expression. Finally, the power in low spatial frequency of a feature predicted its discriminability index. The results suggest that expressive features are perceptually more salient with a higher d’ due to changes at the low-level visual properties, with emotions and configuration affecting perception through top-down processes, as reflected by the response bias. PMID:28267761

Perceptual Load Alters Visual Excitability

ERIC Educational Resources Information Center

Carmel, David; Thorne, Jeremy D.; Rees, Geraint; Lavie, Nilli

2011-01-01

Increasing perceptual load reduces the processing of visual stimuli outside the focus of attention, but the mechanism underlying these effects remains unclear. Here we tested an account attributing the effects of perceptual load to modulations of visual cortex excitability. In contrast to stimulus competition accounts, which propose that load…

I see/hear what you mean: semantic activation in visual word recognition depends on perceptual attention.

PubMed

Connell, Louise; Lynott, Dermot

2014-04-01

How does the meaning of a word affect how quickly we can recognize it? Accounts of visual word recognition allow semantic information to facilitate performance but have neglected the role of modality-specific perceptual attention in activating meaning. We predicted that modality-specific semantic information would differentially facilitate lexical decision and reading aloud, depending on how perceptual attention is implicitly directed by each task. Large-scale regression analyses showed the perceptual modalities involved in representing a word's referent concept influence how easily that word is recognized. Both lexical decision and reading-aloud tasks direct attention toward vision, and are faster and more accurate for strongly visual words. Reading aloud additionally directs attention toward audition and is faster and more accurate for strongly auditory words. Furthermore, the overall semantic effects are as large for reading aloud as lexical decision and are separable from age-of-acquisition effects. These findings suggest that implicitly directing perceptual attention toward a particular modality facilitates representing modality-specific perceptual information in the meaning of a word, which in turn contributes to the lexical decision or reading-aloud response.

Perceptual learning and adult cortical plasticity.

PubMed

Gilbert, Charles D; Li, Wu; Piech, Valentin

2009-06-15

The visual cortex retains the capacity for experience-dependent changes, or plasticity, of cortical function and cortical circuitry, throughout life. These changes constitute the mechanism of perceptual learning in normal visual experience and in recovery of function after CNS damage. Such plasticity can be seen at multiple stages in the visual pathway, including primary visual cortex. The manifestation of the functional changes associated with perceptual learning involve both long term modification of cortical circuits during the course of learning, and short term dynamics in the functional properties of cortical neurons. These dynamics are subject to top-down influences of attention, expectation and perceptual task. As a consequence, each cortical area is an adaptive processor, altering its function in accordance to immediate perceptual demands.

Social grouping: perceptual grouping of objects by cooperative but not competitive relationships in dynamic chase.

PubMed

Yin, Jun; Ding, Xiaowei; Zhou, Jifan; Shui, Rende; Li, Xinyu; Shen, Mowei

2013-10-01

Historically, perceptual grouping is associated with physical principles. This article reports a novel finding that social information-cooperative but not competitive relationships-can drive perceptual grouping of objects in dynamic chase. Particularly, each relationship was constructed with human-generated chasing motions (i.e., two predators and one prey), and its role on perceptual grouping was examined by grouping-induced effect-attentional consequences. The results showed that: (1) Predators can be perceived as a group due to their cooperative relationship, causing attention to automatically spread within grouped predators, thus the response to target appearing on uncued predator is also facilitated; and (2) The attentional effect on competitive predators has no difference from any condition which controls low-level motion patterns, even including the random-motion condition wherein no grouping factor was contained. These findings extend perceptual grouping into the social field, implying that social information gets involved in visual cognition at an early perceptual stage. Copyright © 2013 Elsevier B.V. All rights reserved.

Perceptual inference.

PubMed

Aggelopoulos, Nikolaos C

2015-08-01

Perceptual inference refers to the ability to infer sensory stimuli from predictions that result from internal neural representations built through prior experience. Methods of Bayesian statistical inference and decision theory model cognition adequately by using error sensing either in guiding action or in "generative" models that predict the sensory information. In this framework, perception can be seen as a process qualitatively distinct from sensation, a process of information evaluation using previously acquired and stored representations (memories) that is guided by sensory feedback. The stored representations can be utilised as internal models of sensory stimuli enabling long term associations, for example in operant conditioning. Evidence for perceptual inference is contributed by such phenomena as the cortical co-localisation of object perception with object memory, the response invariance in the responses of some neurons to variations in the stimulus, as well as from situations in which perception can be dissociated from sensation. In the context of perceptual inference, sensory areas of the cerebral cortex that have been facilitated by a priming signal may be regarded as comparators in a closed feedback loop, similar to the better known motor reflexes in the sensorimotor system. The adult cerebral cortex can be regarded as similar to a servomechanism, in using sensory feedback to correct internal models, producing predictions of the outside world on the basis of past experience. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adaptation and perceptual norms

NASA Astrophysics Data System (ADS)

Webster, Michael A.; Yasuda, Maiko; Haber, Sara; Leonard, Deanne; Ballardini, Nicole

2007-02-01

We used adaptation to examine the relationship between perceptual norms--the stimuli observers describe as psychologically neutral, and response norms--the stimulus levels that leave visual sensitivity in a neutral or balanced state. Adapting to stimuli on opposite sides of a neutral point (e.g. redder or greener than white) biases appearance in opposite ways. Thus the adapting stimulus can be titrated to find the unique adapting level that does not bias appearance. We compared these response norms to subjectively defined neutral points both within the same observer (at different retinal eccentricities) and between observers. These comparisons were made for visual judgments of color, image focus, and human faces, stimuli that are very different and may depend on very different levels of processing, yet which share the property that for each there is a well defined and perceptually salient norm. In each case the adaptation aftereffects were consistent with an underlying sensitivity basis for the perceptual norm. Specifically, response norms were similar to and thus covaried with the perceptual norm, and under common adaptation differences between subjectively defined norms were reduced. These results are consistent with models of norm-based codes and suggest that these codes underlie an important link between visual coding and visual experience.

General perceptual contributions to lexical tone normalization.

PubMed

Huang, Jingyuan; Holt, Lori L

2009-06-01

Within tone languages that use pitch variations to contrast meaning, large variability exists in the pitches produced by different speakers. Context-dependent perception may help to resolve this perceptual challenge. However, whether speakers rely on context in contour tone perception is unclear; previous studies have produced inconsistent results. The present study aimed to provide an unambiguous test of the effect of context on contour lexical tone perception and to explore its underlying mechanisms. In three experiments, Mandarin listeners' perception of Mandarin first and second (high-level and mid-rising) tones was investigated with preceding speech and non-speech contexts. Results indicate that the mean fundamental frequency (f0) of a preceding sentence affects perception of contour lexical tones and the effect is contrastive. Following a sentence with a higher-frequency mean f0, the following syllable is more likely to be perceived as a lower frequency lexical tone and vice versa. Moreover, non-speech precursors modeling the mean spectrum of f0 also elicit this effect, suggesting general perceptual processing rather than articulatory-based or speaker-identity-driven mechanisms.

Fusiform Gyrus Dysfunction is Associated with Perceptual Processing Efficiency to Emotional Faces in Adolescent Depression: A Model-Based Approach.

PubMed

Ho, Tiffany C; Zhang, Shunan; Sacchet, Matthew D; Weng, Helen; Connolly, Colm G; Henje Blom, Eva; Han, Laura K M; Mobayed, Nisreen O; Yang, Tony T

2016-01-01

While the extant literature has focused on major depressive disorder (MDD) as being characterized by abnormalities in processing affective stimuli (e.g., facial expressions), little is known regarding which specific aspects of cognition influence the evaluation of affective stimuli, and what are the underlying neural correlates. To investigate these issues, we assessed 26 adolescents diagnosed with MDD and 37 well-matched healthy controls (HCL) who completed an emotion identification task of dynamically morphing faces during functional magnetic resonance imaging (fMRI). We analyzed the behavioral data using a sequential sampling model of response time (RT) commonly used to elucidate aspects of cognition in binary perceptual decision making tasks: the Linear Ballistic Accumulator (LBA) model. Using a hierarchical Bayesian estimation method, we obtained group-level and individual-level estimates of LBA parameters on the facial emotion identification task. While the MDD and HCL groups did not differ in mean RT, accuracy, or group-level estimates of perceptual processing efficiency (i.e., drift rate parameter of the LBA), the MDD group showed significantly reduced responses in left fusiform gyrus compared to the HCL group during the facial emotion identification task. Furthermore, within the MDD group, fMRI signal in the left fusiform gyrus during affective face processing was significantly associated with greater individual-level estimates of perceptual processing efficiency. Our results therefore suggest that affective processing biases in adolescents with MDD are characterized by greater perceptual processing efficiency of affective visual information in sensory brain regions responsible for the early processing of visual information. The theoretical, methodological, and clinical implications of our results are discussed.

Perceptual and Cognitive Factors Imposing “Speed Limits” on Reading Rate: A Study with the Rapid Serial Visual Presentation

PubMed Central

Spinelli, Donatella; Zoccolotti, Pierluigi; De Luca, Maria; Martelli, Marialuisa

2016-01-01

Adults read at high speed, but estimates of their reading rate vary greatly, i.e., from 100 to 1500 words per minute (wpm). This discrepancy is likely due to different recording methods and to the different perceptual and cognitive processes involved in specific test conditions. The present study investigated the origins of these notable differences in RSVP reading rate (RR). In six experiments we investigated the role of many different perceptual and cognitive variables. The presence of a mask caused a steep decline in reading rate, with an estimated masking cost of about 200 wpm. When the decoding process was isolated, RR approached values of 1200 wpm. When the number of stimuli exceeded the short-term memory span, RR decreased to 800 wpm. The semantic context contributed to reading speed only by a factor of 1.4. Finally, eye movements imposed an upper limit on RR (around 300 wpm). Overall, data indicate a speed limit of 300 wpm, which corresponds to the time needed for eye movement execution, i.e., the most time consuming mechanism. Results reconcile differences in reading rates reported by different laboratories and thus provide suggestions for targeting different components of reading rate. PMID:27088226

Factors Affecting Medical Service Quality.

PubMed

Mosadeghrad, Ali Mohammad

2014-02-01

A better understanding of factors influencing quality of medical service can pinpoint better strategies for quality assurance in medical services. This study aimed to identify factors affecting the quality of medical services provided by Iranian physicians. Exploratory in-depth individual interviews were conducted with sixty-four physicians working in various medical institutions in Iran. Individual, organizational and environmental factors enhance or inhibit the quality of medical services. Quality of medical services depends on the personal factors of the physician and patient, and factors pertaining to the healthcare setting and the broader environment. Differences in internal and external factors such as availability of resources, patient cooperation and collaboration among providers affect the quality of medical services and patient outcomes. Supportive leadership, proper planning, education and training and effective management of resources and processes improve the quality of medical services. This article contributes to healthcare theory and practice by developing a conceptual framework for understanding factors that influence medical services quality.

A new taxonomy for perceptual filling-in

PubMed Central

Weil, Rimona S.; Rees, Geraint

2011-01-01

Perceptual filling-in occurs when structures of the visual system interpolate information across regions of visual space where that information is physically absent. It is a ubiquitous and heterogeneous phenomenon, which takes place in different forms almost every time we view the world around us, such as when objects are occluded by other objects or when they fall behind the blind spot. Yet, to date, there is no clear framework for relating these various forms of perceptual filling-in. Similarly, whether these and other forms of filling-in share common mechanisms is not yet known. Here we present a new taxonomy to categorize the different forms of perceptual filling-in. We then examine experimental evidence for the processes involved in each type of perceptual filling-in. Finally, we use established theories of general surface perception to show how contextualizing filling-in using this framework broadens our understanding of the possible shared mechanisms underlying perceptual filling-in. In particular, we consider the importance of the presence of boundaries in determining the phenomenal experience of perceptual filling-in. PMID:21059374

Musically cued gait-training improves both perceptual and motor timing in Parkinson's disease.

PubMed

Benoit, Charles-Etienne; Dalla Bella, Simone; Farrugia, Nicolas; Obrig, Hellmuth; Mainka, Stefan; Kotz, Sonja A

2014-01-01

It is well established that auditory cueing improves gait in patients with idiopathic Parkinson's disease (IPD). Disease-related reductions in speed and step length can be improved by providing rhythmical auditory cues via a metronome or music. However, effects on cognitive aspects of motor control have yet to be thoroughly investigated. If synchronization of movement to an auditory cue relies on a supramodal timing system involved in perceptual, motor, and sensorimotor integration, auditory cueing can be expected to affect both motor and perceptual timing. Here, we tested this hypothesis by assessing perceptual and motor timing in 15 IPD patients before and after a 4-week music training program with rhythmic auditory cueing. Long-term effects were assessed 1 month after the end of the training. Perceptual and motor timing was evaluated with a battery for the assessment of auditory sensorimotor and timing abilities and compared to that of age-, gender-, and education-matched healthy controls. Prior to training, IPD patients exhibited impaired perceptual and motor timing. Training improved patients' performance in tasks requiring synchronization with isochronous sequences, and enhanced their ability to adapt to durational changes in a sequence in hand tapping tasks. Benefits of cueing extended to time perception (duration discrimination and detection of misaligned beats in musical excerpts). The current results demonstrate that auditory cueing leads to benefits beyond gait and support the idea that coupling gait to rhythmic auditory cues in IPD patients relies on a neuronal network engaged in both perceptual and motor timing.

Transfer-appropriate processing in recognition memory: perceptual and conceptual effects on recognition memory depend on task demands.

PubMed

Parks, Colleen M

2013-07-01

Research examining the importance of surface-level information to familiarity in recognition memory tasks is mixed: Sometimes it affects recognition and sometimes it does not. One potential explanation of the inconsistent findings comes from the ideas of dual process theory of recognition and the transfer-appropriate processing framework, which suggest that the extent to which perceptual fluency matters on a recognition test depends in large part on the task demands. A test that recruits perceptual processing for discrimination should show greater perceptual effects and smaller conceptual effects than standard recognition, similar to the pattern of effects found in perceptual implicit memory tasks. This idea was tested in the current experiment by crossing a levels of processing manipulation with a modality manipulation on a series of recognition tests that ranged from conceptual (standard recognition) to very perceptually demanding (a speeded recognition test with degraded stimuli). Results showed that the levels of processing effect decreased and the effect of modality increased when tests were made perceptually demanding. These results support the idea that surface-level features influence performance on recognition tests when they are made salient by the task demands. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Perceptual and Decisional Factors Influencing the Discrimination of Inversion in the Thatcher Illusion

ERIC Educational Resources Information Center

Cornes, Katherine; Donnelly, Nick; Godwin, Hayward; Wenger, Michael J.

2011-01-01

The Thatcher illusion (Thompson, 1980) is considered to be a prototypical illustration of the notion that face perception is dependent on configural processes and representations. We explored this idea by examining the relative contributions of perceptual and decisional processes to the ability of observers to identify the orientation of two…

Tuned by experience: How orientation probability modulates early perceptual processing.

PubMed

Jabar, Syaheed B; Filipowicz, Alex; Anderson, Britt

2017-09-01

Probable stimuli are more often and more quickly detected. While stimulus probability is known to affect decision-making, it can also be explained as a perceptual phenomenon. Using spatial gratings, we have previously shown that probable orientations are also more precisely estimated, even while participants remained naive to the manipulation. We conducted an electrophysiological study to investigate the effect that probability has on perception and visual-evoked potentials. In line with previous studies on oddballs and stimulus prevalence, low-probability orientations were associated with a greater late positive 'P300' component which might be related to either surprise or decision-making. However, the early 'C1' component, thought to reflect V1 processing, was dampened for high-probability orientations while later P1 and N1 components were unaffected. Exploratory analyses revealed a participant-level correlation between C1 and P300 amplitudes, suggesting a link between perceptual processing and decision-making. We discuss how these probability effects could be indicative of sharpening of neurons preferring the probable orientations, due either to perceptual learning, or to feature-based attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Effects of Goal Relevance and Perceptual Features on Emotional Items and Associative Memory.

PubMed

Mao, Wei B; An, Shu; Yang, Xiao F

2017-01-01

Showing an emotional item in a neutral background scene often leads to enhanced memory for the emotional item and impaired associative memory for background details. Meanwhile, both top-down goal relevance and bottom-up perceptual features played important roles in memory binding. We conducted two experiments and aimed to further examine the effects of goal relevance and perceptual features on emotional items and associative memory. By manipulating goal relevance (asking participants to categorize only each item image as living or non-living or to categorize each whole composite picture consisted of item image and background scene as natural scene or manufactured scene) and perceptual features (controlling visual contrast and visual familiarity) in two experiments, we found that both high goal relevance and salient perceptual features (high salience of items vs. high familiarity of items) could promote emotional item memory, but they had different effects on associative memory for emotional items and neutral backgrounds. Specifically, high goal relevance and high perceptual-salience of items could jointly impair the associative memory for emotional items and neutral backgrounds, while the effect of item familiarity on associative memory for emotional items would be modulated by goal relevance. High familiarity of items could increase associative memory for negative items and neutral backgrounds only in the low goal relevance condition. These findings suggest the effect of emotion on associative memory is not only related to attentional capture elicited by emotion, but also can be affected by goal relevance and perceptual features of stimulus.

Perceptual Training Strongly Improves Visual Motion Perception in Schizophrenia

ERIC Educational Resources Information Center

Norton, Daniel J.; McBain, Ryan K.; Ongur, Dost; Chen, Yue

2011-01-01

Schizophrenia patients exhibit perceptual and cognitive deficits, including in visual motion processing. Given that cognitive systems depend upon perceptual inputs, improving patients' perceptual abilities may be an effective means of cognitive intervention. In healthy people, motion perception can be enhanced through perceptual learning, but it…

Thin-slice vision: inference of confidence measure from perceptual video quality

NASA Astrophysics Data System (ADS)

Hameed, Abdul; Balas, Benjamin; Dai, Rui

2016-11-01

There has been considerable research on thin-slice judgments, but no study has demonstrated the predictive validity of confidence measures when assessors watch videos acquired from communication systems, in which the perceptual quality of videos could be degraded by limited bandwidth and unreliable network conditions. This paper studies the relationship between high-level thin-slice judgments of human behavior and factors that contribute to perceptual video quality. Based on a large number of subjective test results, it has been found that the confidence of a single individual present in all the videos, called speaker's confidence (SC), could be predicted by a list of features that contribute to perceptual video quality. Two prediction models, one based on artificial neural network and the other based on a decision tree, were built to predict SC. Experimental results have shown that both prediction models can result in high correlation measures.

Skilled Deaf Readers have an Enhanced Perceptual Span in Reading

PubMed Central

Bélanger, Nathalie N.; Slattery, Timothy J.; Mayberry, Rachel I.; Rayner, Keith

2013-01-01

Recent evidence suggests that deaf people have enhanced visual attention to simple stimuli in the parafovea in comparison to hearing people. Although a large part of reading involves processing the fixated words in foveal vision, readers also utilize information in parafoveal vision to pre-process upcoming words and decide where to look next. We investigated whether auditory deprivation affects low-level visual processing during reading, and compared the perceptual span of deaf signers who were skilled and less skilled readers to that of skilled hearing readers. Compared to hearing readers, deaf readers had a larger perceptual span than would be expected by their reading ability. These results provide the first evidence that deaf readers’ enhanced attentional allocation to the parafovea is used during a complex cognitive task such as reading. PMID:22683830

Auditory perceptual simulation: Simulating speech rates or accents?

PubMed

Zhou, Peiyun; Christianson, Kiel

2016-07-01

When readers engage in Auditory Perceptual Simulation (APS) during silent reading, they mentally simulate characteristics of voices attributed to a particular speaker or a character depicted in the text. Previous research found that auditory perceptual simulation of a faster native English speaker during silent reading led to shorter reading times that auditory perceptual simulation of a slower non-native English speaker. Yet, it was uncertain whether this difference was triggered by the different speech rates of the speakers, or by the difficulty of simulating an unfamiliar accent. The current study investigates this question by comparing faster Indian-English speech and slower American-English speech in the auditory perceptual simulation paradigm. Analyses of reading times of individual words and the full sentence reveal that the auditory perceptual simulation effect again modulated reading rate, and auditory perceptual simulation of the faster Indian-English speech led to faster reading rates compared to auditory perceptual simulation of the slower American-English speech. The comparison between this experiment and the data from Zhou and Christianson (2016) demonstrate further that the "speakers'" speech rates, rather than the difficulty of simulating a non-native accent, is the primary mechanism underlying auditory perceptual simulation effects. Copyright © 2016 Elsevier B.V. All rights reserved.

A Neural Signature Encoding Decisions under Perceptual Ambiguity

PubMed Central

Sun, Sai; Yu, Rongjun

2017-01-01

Abstract People often make perceptual decisions with ambiguous information, but it remains unclear whether the brain has a common neural substrate that encodes various forms of perceptual ambiguity. Here, we used three types of perceptually ambiguous stimuli as well as task instructions to examine the neural basis for both stimulus-driven and task-driven perceptual ambiguity. We identified a neural signature, the late positive potential (LPP), that encoded a general form of stimulus-driven perceptual ambiguity. In addition to stimulus-driven ambiguity, the LPP was also modulated by ambiguity in task instructions. To further specify the functional role of the LPP and elucidate the relationship between stimulus ambiguity, behavioral response, and the LPP, we employed regression models and found that the LPP was specifically associated with response latency and confidence rating, suggesting that the LPP encoded decisions under perceptual ambiguity. Finally, direct behavioral ratings of stimulus and task ambiguity confirmed our neurophysiological findings, which could not be attributed to differences in eye movements either. Together, our findings argue for a common neural signature that encodes decisions under perceptual ambiguity but is subject to the modulation of task ambiguity. Our results represent an essential first step toward a complete neural understanding of human perceptual decision making. PMID:29177189

A Neural Signature Encoding Decisions under Perceptual Ambiguity.

PubMed

Sun, Sai; Yu, Rongjun; Wang, Shuo

2017-01-01

People often make perceptual decisions with ambiguous information, but it remains unclear whether the brain has a common neural substrate that encodes various forms of perceptual ambiguity. Here, we used three types of perceptually ambiguous stimuli as well as task instructions to examine the neural basis for both stimulus-driven and task-driven perceptual ambiguity. We identified a neural signature, the late positive potential (LPP), that encoded a general form of stimulus-driven perceptual ambiguity. In addition to stimulus-driven ambiguity, the LPP was also modulated by ambiguity in task instructions. To further specify the functional role of the LPP and elucidate the relationship between stimulus ambiguity, behavioral response, and the LPP, we employed regression models and found that the LPP was specifically associated with response latency and confidence rating, suggesting that the LPP encoded decisions under perceptual ambiguity. Finally, direct behavioral ratings of stimulus and task ambiguity confirmed our neurophysiological findings, which could not be attributed to differences in eye movements either. Together, our findings argue for a common neural signature that encodes decisions under perceptual ambiguity but is subject to the modulation of task ambiguity. Our results represent an essential first step toward a complete neural understanding of human perceptual decision making.

Is sequence awareness mandatory for perceptual sequence learning: An assessment using a pure perceptual sequence learning design.

PubMed

Deroost, Natacha; Coomans, Daphné

2018-02-01

We examined the role of sequence awareness in a pure perceptual sequence learning design. Participants had to react to the target's colour that changed according to a perceptual sequence. By varying the mapping of the target's colour onto the response keys, motor responses changed randomly. The effect of sequence awareness on perceptual sequence learning was determined by manipulating the learning instructions (explicit versus implicit) and assessing the amount of sequence awareness after the experiment. In the explicit instruction condition (n = 15), participants were instructed to intentionally search for the colour sequence, whereas in the implicit instruction condition (n = 15), they were left uninformed about the sequenced nature of the task. Sequence awareness after the sequence learning task was tested by means of a questionnaire and the process-dissociation-procedure. The results showed that the instruction manipulation had no effect on the amount of perceptual sequence learning. Based on their report to have actively applied their sequence knowledge during the experiment, participants were subsequently regrouped in a sequence strategy group (n = 14, of which 4 participants from the implicit instruction condition and 10 participants from the explicit instruction condition) and a no-sequence strategy group (n = 16, of which 11 participants from the implicit instruction condition and 5 participants from the explicit instruction condition). Only participants of the sequence strategy group showed reliable perceptual sequence learning and sequence awareness. These results indicate that perceptual sequence learning depends upon the continuous employment of strategic cognitive control processes on sequence knowledge. Sequence awareness is suggested to be a necessary but not sufficient condition for perceptual learning to take place. Copyright © 2018 Elsevier B.V. All rights reserved.

The Neural Correlates of Hierarchical Predictions for Perceptual Decisions.

PubMed

Weilnhammer, Veith A; Stuke, Heiner; Sterzer, Philipp; Schmack, Katharina

2018-05-23

Sensory information is inherently noisy, sparse, and ambiguous. In contrast, visual experience is usually clear, detailed, and stable. Bayesian theories of perception resolve this discrepancy by assuming that prior knowledge about the causes underlying sensory stimulation actively shapes perceptual decisions. The CNS is believed to entertain a generative model aligned to dynamic changes in the hierarchical states of our volatile sensory environment. Here, we used model-based fMRI to study the neural correlates of the dynamic updating of hierarchically structured predictions in male and female human observers. We devised a crossmodal associative learning task with covertly interspersed ambiguous trials in which participants engaged in hierarchical learning based on changing contingencies between auditory cues and visual targets. By inverting a Bayesian model of perceptual inference, we estimated individual hierarchical predictions, which significantly biased perceptual decisions under ambiguity. Although "high-level" predictions about the cue-target contingency correlated with activity in supramodal regions such as orbitofrontal cortex and hippocampus, dynamic "low-level" predictions about the conditional target probabilities were associated with activity in retinotopic visual cortex. Our results suggest that our CNS updates distinct representations of hierarchical predictions that continuously affect perceptual decisions in a dynamically changing environment. SIGNIFICANCE STATEMENT Bayesian theories posit that our brain entertains a generative model to provide hierarchical predictions regarding the causes of sensory information. Here, we use behavioral modeling and fMRI to study the neural underpinnings of such hierarchical predictions. We show that "high-level" predictions about the strength of dynamic cue-target contingencies during crossmodal associative learning correlate with activity in orbitofrontal cortex and the hippocampus, whereas "low-level" conditional

Perceptual discrimination difficulty and familiarity in the Uncanny Valley: more like a "Happy Valley".

PubMed

Cheetham, Marcus; Suter, Pascal; Jancke, Lutz

2014-01-01

The Uncanny Valley Hypothesis (UVH) predicts that greater difficulty perceptually discriminating between categorically ambiguous human and humanlike characters (e.g., highly realistic robot) evokes negatively valenced (i.e., uncanny) affect. An ABX perceptual discrimination task and signal detection analysis was used to examine the profile of perceptual discrimination (PD) difficulty along the UVH' dimension of human likeness (DHL). This was represented using avatar-to-human morph continua. Rejecting the implicitly assumed profile of PD difficulty underlying the UVH' prediction, Experiment 1 showed that PD difficulty was reduced for categorically ambiguous faces but, notably, enhanced for human faces. Rejecting the UVH' predicted relationship between PD difficulty and negative affect (assessed in terms of the UVH' familiarity dimension), Experiment 2 demonstrated that greater PD difficulty correlates with more positively valenced affect. Critically, this effect was strongest for the ambiguous faces, suggesting a correlative relationship between PD difficulty and feelings of familiarity more consistent with the metaphor happy valley. This relationship is also consistent with a fluency amplification instead of the hitherto proposed hedonic fluency account of affect along the DHL. Experiment 3 found no evidence that the asymmetry in the profile of PD along the DHL is attributable to a differential processing bias (cf. other-race effect), i.e., processing avatars at a category level but human faces at an individual level. In conclusion, the present data for static faces show clear effects that, however, strongly challenge the UVH' implicitly assumed profile of PD difficulty along the DHL and the predicted relationship between this and feelings of familiarity.

Effects of selective attention on perceptual filling-in.

PubMed

De Weerd, P; Smith, E; Greenberg, P

2006-03-01

After few seconds, a figure steadily presented in peripheral vision becomes perceptually filled-in by its background, as if it "disappeared". We report that directing attention to the color, shape, or location of a figure increased the probability of perceiving filling-in compared to unattended figures, without modifying the time required for filling-in. This effect could be augmented by boosting attention. Furthermore, the frequency distribution of filling-in response times for attended figures could be predicted by multiplying the frequencies of response times for unattended figures with a constant. We propose that, after failure of figure-ground segregation, the neural interpolation processes that produce perceptual filling-in are enhanced in attended figure regions. As filling-in processes are involved in surface perception, the present study demonstrates that even very early visual processes are subject to modulation by cognitive factors.

Psychomotor and Perceptual Speed Abilities and Skilled Performance.

DTIC Science & Technology

1999-02-01

of the perceptual speed and touch-panel psychomotor tests used in the current project were administered to School of Dentistry students. Although...progress). Touch-panel monitor based psychomotor tests for predicting skilled performance: An exploratory study with School of Dentistry students...Paper to be submitted for presentation at the 1999 Human Factors and Ergonomics Society annual meeting. Ackerman, P. L., & Kanfer, R. (1993

Animacy, perceptual load, and inattentional blindness.

PubMed

Calvillo, Dustin P; Jackson, Russell E

2014-06-01

Inattentional blindness is the failure to notice unexpected objects in a visual scene while engaging in an attention-demanding task. We examined the effects of animacy and perceptual load on inattentional blindness. Participants searched for a category exemplar under low or high perceptual load. On the last trial, the participants were exposed to an unexpected object that was either animate or inanimate. Unexpected objects were detected more frequently when they were animate rather than inanimate, and more frequently with low than with high perceptual loads. We also measured working memory capacity and found that it predicted the detection of unexpected objects, but only with high perceptual loads. The results are consistent with the animate-monitoring hypothesis, which suggests that animate objects capture attention because of the importance of the detection of animate objects in ancestral hunter-gatherer environments.

Beyond Perceptual Symbols: A Call for Representational Pluralism

ERIC Educational Resources Information Center

Dove, Guy

2009-01-01

Recent evidence from cognitive neuroscience suggests that certain cognitive processes employ perceptual representations. Inspired by this evidence, a few researchers have proposed that cognition is inherently perceptual. They have developed an innovative theoretical approach that rests on the notion of perceptual simulation and marshaled several…

The Role of Inhibition in Moving beyond Perceptually Focused Noun Extensions

ERIC Educational Resources Information Center

Snape, Simon; Krott, Andrea

2018-01-01

When young children interpret novel nouns, they tend to be very much affected by the perceptual features of the referent objects, especially shape. This article investigates whether children might inhibit a prepotent tendency to base novel nouns on the shape of referent objects in order to base them on conceptual features (i.e. taxonomic object…

Fusiform Gyrus Dysfunction is Associated with Perceptual Processing Efficiency to Emotional Faces in Adolescent Depression: A Model-Based Approach

PubMed Central

Ho, Tiffany C.; Zhang, Shunan; Sacchet, Matthew D.; Weng, Helen; Connolly, Colm G.; Henje Blom, Eva; Han, Laura K. M.; Mobayed, Nisreen O.; Yang, Tony T.

2016-01-01

While the extant literature has focused on major depressive disorder (MDD) as being characterized by abnormalities in processing affective stimuli (e.g., facial expressions), little is known regarding which specific aspects of cognition influence the evaluation of affective stimuli, and what are the underlying neural correlates. To investigate these issues, we assessed 26 adolescents diagnosed with MDD and 37 well-matched healthy controls (HCL) who completed an emotion identification task of dynamically morphing faces during functional magnetic resonance imaging (fMRI). We analyzed the behavioral data using a sequential sampling model of response time (RT) commonly used to elucidate aspects of cognition in binary perceptual decision making tasks: the Linear Ballistic Accumulator (LBA) model. Using a hierarchical Bayesian estimation method, we obtained group-level and individual-level estimates of LBA parameters on the facial emotion identification task. While the MDD and HCL groups did not differ in mean RT, accuracy, or group-level estimates of perceptual processing efficiency (i.e., drift rate parameter of the LBA), the MDD group showed significantly reduced responses in left fusiform gyrus compared to the HCL group during the facial emotion identification task. Furthermore, within the MDD group, fMRI signal in the left fusiform gyrus during affective face processing was significantly associated with greater individual-level estimates of perceptual processing efficiency. Our results therefore suggest that affective processing biases in adolescents with MDD are characterized by greater perceptual processing efficiency of affective visual information in sensory brain regions responsible for the early processing of visual information. The theoretical, methodological, and clinical implications of our results are discussed. PMID:26869950

Relationship of extinction to perceptual thresholds for single stimuli.

PubMed

Meador, K J; Ray, P G; Day, L J; Loring, D W

2001-04-24

To demonstrate the effects of target stimulus intensity on extinction to double simultaneous stimuli. Attentional deficits contribute to extinction in patients with brain lesions, but extinction (i.e., masking) can also be produced in healthy subjects. The relationship of extinction to perceptual thresholds for single stimuli remains uncertain. Brief electrical pulses were applied simultaneously to the left and right index fingers of 16 healthy volunteers (8 young and 8 elderly adults) and 4 patients with right brain stroke (RBS). The stimulus to be perceived (i.e., target stimulus) was given at the lowest perceptual threshold to perceive any single stimulus (i.e., Minimal) and at the threshold to perceive 100% of single stimuli. The mask stimulus (i.e., stimulus given to block the target) was applied to the contralateral hand at intensities just below discomfort. Extinction was less for target stimuli at 100% than Minimal threshold for healthy subjects. Extinction of left targets was greater in patients with RBS than elderly control subjects. Left targets were extinguished less than right in healthy subjects. In contrast, the majority of left targets were extinguished in patients with RBS even when right mask intensity was reduced below right 100% threshold for single stimuli. RBS patients had less extinction for right targets despite having greater left mask - threshold difference than control subjects. In patients with RBS, right "targets" at 100% threshold extinguished left "masks" (20%) almost as frequently as left masks extinguished right targets (32%). Subtle changes in target intensity affect extinction in healthy adults. Asymmetries in mask and target intensities (relative to single-stimulus perceptual thresholds) affect extinction in RBS patients less for left targets but more for right targets as compared with control subjects.

A Perceptual Study of Girls Education, Its Factors and Challenges in South Kashmir

ERIC Educational Resources Information Center

Gul, Showkeen Bilal Ahmad; Khan, Zebun Nisa

2015-01-01

Education is accepted as an important tool for human development in all dimensions of life, it is at same level of significance for boys and girls. Despite this recognition, girls are one of the most vulnerable groups, deprived of education by various socio-cultural, economical and political reasons. The present study is a perceptual study, which…

Perceptual Learning in the Absence of Task or Stimulus Specificity

PubMed Central

Webb, Ben S.; Roach, Neil W.; McGraw, Paul V.

2007-01-01

Performance on most sensory tasks improves with practice. When making particularly challenging sensory judgments, perceptual improvements in performance are tightly coupled to the trained task and stimulus configuration. The form of this specificity is believed to provide a strong indication of which neurons are solving the task or encoding the learned stimulus. Here we systematically decouple task- and stimulus-mediated components of trained improvements in perceptual performance and show that neither provides an adequate description of the learning process. Twenty-four human subjects trained on a unique combination of task (three-element alignment or bisection) and stimulus configuration (vertical or horizontal orientation). Before and after training, we measured subjects' performance on all four task-configuration combinations. What we demonstrate for the first time is that learning does actually transfer across both task and configuration provided there is a common spatial axis to the judgment. The critical factor underlying the transfer of learning effects is not the task or stimulus arrangements themselves, but rather the recruitment of commons sets of neurons most informative for making each perceptual judgment. PMID:18094748

Dissociation between Conceptual and Perceptual Implicit Memory: Evidence from Patients with Frontal and Occipital Lobe Lesions

PubMed Central

Gong, Liang; Wang, JiHua; Yang, XuDong; Feng, Lei; Li, Xiu; Gu, Cui; Wang, MeiHong; Hu, JiaYun; Cheng, Huaidong

2016-01-01

The latest neuroimaging studies about implicit memory (IM) have revealed that different IM types may be processed by different parts of the brain. However, studies have rarely examined what subtypes of IM processes are affected in patients with various brain injuries. Twenty patients with frontal lobe injury, 25 patients with occipital lobe injury, and 29 healthy controls (HC) were recruited for the study. Two subtypes of IM were investigated by using structurally parallel perceptual (picture identification task) and conceptual (category exemplar generation task) IM tests in the three groups, as well as explicit memory (EM) tests. The results indicated that the priming of conceptual IM and EM tasks in patients with frontal lobe injury was poorer than that observed in HC, while perceptual IM was identical between the two groups. By contrast, the priming of perceptual IM in patients with occipital lobe injury was poorer than that in HC, whereas the priming of conceptual IM and EM was similar to that in HC. This double dissociation between perceptual and conceptual IM across the brain areas implies that occipital lobes may participate in perceptual IM, while frontal lobes may be involved in processing conceptual memory. PMID:26793093

Perceptual, durational and tongue displacement measures following articulation therapy for rhotic sound errors.

PubMed

Bressmann, Tim; Harper, Susan; Zhylich, Irina; Kulkarni, Gajanan V

2016-01-01

Outcomes of articulation therapy for rhotic errors are usually assessed perceptually. However, our understanding of associated changes of tongue movement is limited. This study described perceptual, durational and tongue displacement changes over 10 sessions of articulation therapy for /ɹ/ in six children. Four of the participants also received ultrasound biofeedback of their tongue shape. Speech and tongue movement were recorded pre-therapy, after 5 sessions, in the final session and at a one month follow-up. Perceptually, listeners perceived improvement and classified more productions as /ɹ/ in the final and follow-up assessments. The durations of VɹV syllables at the midway point of the therapy were longer. Cumulative tongue displacement increased in the final session. The average standard deviation was significantly higher in the middle and final assessments. The duration and tongue displacement measures illustrated how articulation therapy affected tongue movement and may be useful for outcomes research about articulation therapy.

Stimulus and response conflict processing during perceptual decision making.

PubMed

Wendelken, Carter; Ditterich, Jochen; Bunge, Silvia A; Carter, Cameron S

2009-12-01

Encoding and dealing with conflicting information is essential for successful decision making in a complex environment. In the present fMRI study, stimulus conflict and response conflict are contrasted in the context of a perceptual decision-making dot-motion discrimination task. Stimulus conflict was manipulated by varying dot-motion coherence along task-relevant and task-irrelevant dimensions. Response conflict was manipulated by varying whether or not competing stimulus dimensions provided evidence for the same or different responses. The right inferior frontal gyrus was involved specifically in the resolution of stimulus conflict, whereas the dorsal anterior cingulate cortex was shown to be sensitive to response conflict. Additionally, two regions that have been linked to perceptual decision making with dot-motion stimuli in monkey physiology studies were differentially engaged by stimulus conflict and response conflict. The middle temporal area, previously linked to processing of motion, was strongly affected by the presence of stimulus conflict. On the other hand, the superior parietal lobe, previously associated with accumulation of evidence for a response, was affected by the presence of response conflict. These results shed light on the neural mechanisms that support decision making in the presence of conflict, a cognitive operation fundamental to both basic survival and high-level cognition.

The perceptual significance of high-frequency energy in the human voice.

PubMed

Monson, Brian B; Hunter, Eric J; Lotto, Andrew J; Story, Brad H

2014-01-01

While human vocalizations generate acoustical energy at frequencies up to (and beyond) 20 kHz, the energy at frequencies above about 5 kHz has traditionally been neglected in speech perception research. The intent of this paper is to review (1) the historical reasons for this research trend and (2) the work that continues to elucidate the perceptual significance of high-frequency energy (HFE) in speech and singing. The historical and physical factors reveal that, while HFE was believed to be unnecessary and/or impractical for applications of interest, it was never shown to be perceptually insignificant. Rather, the main causes for focus on low-frequency energy appear to be because the low-frequency portion of the speech spectrum was seen to be sufficient (from a perceptual standpoint), or the difficulty of HFE research was too great to be justifiable (from a technological standpoint). The advancement of technology continues to overcome concerns stemming from the latter reason. Likewise, advances in our understanding of the perceptual effects of HFE now cast doubt on the first cause. Emerging evidence indicates that HFE plays a more significant role than previously believed, and should thus be considered in speech and voice perception research, especially in research involving children and the hearing impaired.

The perceptual significance of high-frequency energy in the human voice

PubMed Central

Monson, Brian B.; Hunter, Eric J.; Lotto, Andrew J.; Story, Brad H.

2014-01-01

While human vocalizations generate acoustical energy at frequencies up to (and beyond) 20 kHz, the energy at frequencies above about 5 kHz has traditionally been neglected in speech perception research. The intent of this paper is to review (1) the historical reasons for this research trend and (2) the work that continues to elucidate the perceptual significance of high-frequency energy (HFE) in speech and singing. The historical and physical factors reveal that, while HFE was believed to be unnecessary and/or impractical for applications of interest, it was never shown to be perceptually insignificant. Rather, the main causes for focus on low-frequency energy appear to be because the low-frequency portion of the speech spectrum was seen to be sufficient (from a perceptual standpoint), or the difficulty of HFE research was too great to be justifiable (from a technological standpoint). The advancement of technology continues to overcome concerns stemming from the latter reason. Likewise, advances in our understanding of the perceptual effects of HFE now cast doubt on the first cause. Emerging evidence indicates that HFE plays a more significant role than previously believed, and should thus be considered in speech and voice perception research, especially in research involving children and the hearing impaired. PMID:24982643

The Effects of Goal Relevance and Perceptual Features on Emotional Items and Associative Memory

PubMed Central

Mao, Wei B.; An, Shu; Yang, Xiao F.

2017-01-01

Showing an emotional item in a neutral background scene often leads to enhanced memory for the emotional item and impaired associative memory for background details. Meanwhile, both top–down goal relevance and bottom–up perceptual features played important roles in memory binding. We conducted two experiments and aimed to further examine the effects of goal relevance and perceptual features on emotional items and associative memory. By manipulating goal relevance (asking participants to categorize only each item image as living or non-living or to categorize each whole composite picture consisted of item image and background scene as natural scene or manufactured scene) and perceptual features (controlling visual contrast and visual familiarity) in two experiments, we found that both high goal relevance and salient perceptual features (high salience of items vs. high familiarity of items) could promote emotional item memory, but they had different effects on associative memory for emotional items and neutral backgrounds. Specifically, high goal relevance and high perceptual-salience of items could jointly impair the associative memory for emotional items and neutral backgrounds, while the effect of item familiarity on associative memory for emotional items would be modulated by goal relevance. High familiarity of items could increase associative memory for negative items and neutral backgrounds only in the low goal relevance condition. These findings suggest the effect of emotion on associative memory is not only related to attentional capture elicited by emotion, but also can be affected by goal relevance and perceptual features of stimulus. PMID:28790943

Natural texture retrieval based on perceptual similarity measurement

NASA Astrophysics Data System (ADS)

Gao, Ying; Dong, Junyu; Lou, Jianwen; Qi, Lin; Liu, Jun

2018-04-01

A typical texture retrieval system performs feature comparison and might not be able to make human-like judgments of image similarity. Meanwhile, it is commonly known that perceptual texture similarity is difficult to be described by traditional image features. In this paper, we propose a new texture retrieval scheme based on texture perceptual similarity. The key of the proposed scheme is that prediction of perceptual similarity is performed by learning a non-linear mapping from image features space to perceptual texture space by using Random Forest. We test the method on natural texture dataset and apply it on a new wallpapers dataset. Experimental results demonstrate that the proposed texture retrieval scheme with perceptual similarity improves the retrieval performance over traditional image features.

The perseverative worry bout: A review of cognitive, affective and motivational factors that contribute to worry perseveration.

PubMed

Davey, Graham C L; Meeten, F

2016-12-01

This paper reviews the cognitive, affective and attentional factors that contribute to individual perseverative worry bouts. We describe how automatic biases in attentional and interpretational processes contribute to threat detection and to the inclusion of negative intrusive thoughts into the worry stream typical of the "what if …?" thinking style of pathological worriers. The review also describes processes occurring downstream from these perceptual biases that also facilitate perseveration, including cognitive biases in beliefs about the nature of the worry process, the automatic deployment of strict goal-directed responses for dealing with the threat, the role of negative mood in facilitating effortful forms of information processing (i.e. systematic information processing styles), and in providing negative information for evaluating the success of the worry bout. We also consider the clinical implications of this model for an integrated intervention programme for pathological worrying. Copyright © 2016 Elsevier B.V. All rights reserved.

Perceptually specific and perceptually non-specific influences on rereading benefits for spatially transformed text: evidence from eye movements.

PubMed

Sheridan, Heather; Reingold, Eyal M

2012-12-01

The present study used eye tracking methodology to examine rereading benefits for spatially transformed text. Eye movements were monitored while participants read the same target word twice, in two different low-constraint sentence frames. The congruency of perceptual processing was manipulated by either applying the same type of transformation to the word during the first and second presentations (i.e., the congruent condition), or employing two different types of transformations across the two presentations of the word (i.e., the incongruent condition). Perceptual specificity effects were demonstrated such that fixation times for the second presentation of the target word were shorter for the congruent condition compared to the incongruent condition. Moreover, we demonstrated an additional perceptually non-specific effect such that second reading fixation times were shorter for the incongruent condition relative to a baseline condition that employed a normal typography (i.e., non-transformed) during the first presentation and a transformation during the second presentation. Both of these effects (i.e., perceptually specific and perceptually non-specific) were similar in magnitude for high and low frequency words, and both effects persisted across a 1 week lag between the first and second readings. We discuss the present findings in the context of the distinction between conscious and unconscious memory, and the distinction between perceptually versus conceptually driven processing. Copyright © 2012 Elsevier Inc. All rights reserved.

Topographic generalization of tactile perceptual learning.

PubMed

Harrar, Vanessa; Spence, Charles; Makin, Tamar R

2014-02-01

Perceptual learning can improve our sensory abilities. Understanding its underlying mechanisms, in particular, when perceptual learning generalizes, has become a focus of research and controversy. Specifically, there is little consensus regarding the extent to which tactile perceptual learning generalizes across fingers. We measured tactile orientation discrimination abilities on 4 fingers (index and middle fingers of both hands), using psychophysical measures, before and after 4 training sessions on 1 finger. Given the somatotopic organization of the hand representation in the somatosensory cortex, the topography of the cortical areas underlying tactile perceptual learning can be inferred from the pattern of generalization across fingers; only fingers sharing cortical representation with the trained finger ought to improve with it. Following training, performance improved not only for the trained finger but also for its adjacent and homologous fingers. Although these fingers were not exposed to training, they nevertheless demonstrated similar levels of learning as the trained finger. Conversely, the performance of the finger that was neither adjacent nor homologous to the trained finger was unaffected by training, despite the fact that our procedure was designed to enhance generalization, as described in recent visual perceptual learning research. This pattern of improved performance is compatible with previous reports of neuronal receptive fields (RFs) in the primary somatosensory cortex (SI) spanning adjacent and homologous digits. We conclude that perceptual learning rooted in low-level cortex can still generalize, and suggest potential applications for the neurorehabilitation of syndromes associated with maladaptive plasticity in SI. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Perceptual-Motor Behavior and Educational Processes.

ERIC Educational Resources Information Center

Cratty, Bryant J.

Addressed to elementary school and special class teachers, the text presents research-based information on perceptual-motor behavior and education, including movement and the human personality, research guidelines, and movement activities in general education. Special education is considered and perceptual motor abilities are discussed with…

ViA: a perceptual visualization assistant

NASA Astrophysics Data System (ADS)

Healey, Chris G.; St. Amant, Robert; Elhaddad, Mahmoud S.

2000-05-01

This paper describes an automated visualized assistant called ViA. ViA is designed to help users construct perceptually optical visualizations to represent, explore, and analyze large, complex, multidimensional datasets. We have approached this problem by studying what is known about the control of human visual attention. By harnessing the low-level human visual system, we can support our dual goals of rapid and accurate visualization. Perceptual guidelines that we have built using psychophysical experiments form the basis for ViA. ViA uses modified mixed-initiative planning algorithms from artificial intelligence to search of perceptually optical data attribute to visual feature mappings. Our perceptual guidelines are integrated into evaluation engines that provide evaluation weights for a given data-feature mapping, and hints on how that mapping might be improved. ViA begins by asking users a set of simple questions about their dataset and the analysis tasks they want to perform. Answers to these questions are used in combination with the evaluation engines to identify and intelligently pursue promising data-feature mappings. The result is an automatically-generated set of mappings that are perceptually salient, but that also respect the context of the dataset and users' preferences about how they want to visualize their data.

Comparing perceptual and preferential decision making.

PubMed

Dutilh, Gilles; Rieskamp, Jörg

2016-06-01

Perceptual and preferential decision making have been studied largely in isolation. Perceptual decisions are considered to be at a non-deliberative cognitive level and have an outside criterion that defines the quality of decisions. Preferential decisions are considered to be at a higher cognitive level and the quality of decisions depend on the decision maker's subjective goals. Besides these crucial differences, both types of decisions also have in common that uncertain information about the choice situation has to be processed before a decision can be made. The present work aims to acknowledge the commonalities of both types of decision making to lay bare the crucial differences. For this aim we examine perceptual and preferential decisions with a novel choice paradigm that uses the identical stimulus material for both types of decisions. This paradigm allows us to model the decisions and response times of both types of decisions with the same sequential sampling model, the drift diffusion model. The results illustrate that the different incentive structure in both types of tasks changes people's behavior so that they process information more efficiently and respond more cautiously in the perceptual as compared to the preferential task. These findings set out a perspective for further integration of perceptual and preferential decision making in a single ramework.

The perceptual chunking of speech: a demonstration using ERPs.

PubMed

Gilbert, Annie C; Boucher, Victor J; Jemel, Boutheina

2015-04-07

In tasks involving the learning of verbal or non-verbal sequences, groupings are spontaneously produced. These groupings are generally marked by a lengthening of final elements and have been attributed to a domain-general perceptual chunking linked to working memory. Yet, no study has shown how this domain-general chunking applies to speech processing, partly because of the traditional view that chunking involves a conceptual recoding of meaningful verbal items like words (Miller, 1956). The present study provides a demonstration of the perceptual chunking of speech by way of two experiments using evoked Positive Shifts (PSs), which capture on-line neural responses to marks of various groups. We observed listeners׳ response to utterances (Experiment 1) and meaningless series of syllables (Experiment 2) containing changing intonation and temporal marks, while also examining how these marks affect the recognition of heard items. The results show that, across conditions - and irrespective of the presence of meaningful items - PSs are specifically evoked by groups marked by lengthening. Moreover, this on-line detection of marks corresponds to characteristic grouping effects on listeners' immediate recognition of heard items, which suggests chunking effects linked to working memory. These findings bear out a perceptual chunking of speech input in terms of groups marked by lengthening, which constitute the defining marks of a domain-general chunking. Copyright © 2015 Elsevier B.V. All rights reserved.

Time change of perceptual reversal of ambiguous figures by rTMS.

PubMed

Nojima, K; Ge, S; Katayama, Y; Iramina, K

2010-01-01

The aim of this study was to investigate the effect of stimulus frequency and number of pulses during rTMS (repetitive transcranial magnetic stimulation) on the phenomenon of perceptual reversal. Particularly, we focused on the temporal dynamics of perceptual reversal in the right SPL (superior parietal lobule), using the spinning wheel illusion. We measured the IRT (inter-reversal time) of perceptual reversal. To investigate whether stimulus frequency or the number of pulses is critical for the rTMS effect, we applied the following schedules over the right SPL and the right PTL (posterior temporal lobe): 0.25Hz 60 pulses, 0.25Hz 120pulses, 0.5Hz 120 pulses, and 1Hz 120 pulses biphasic rTMS at 90% of the resting motor threshold. As a control, we included a No-TMS condition. The results showed that rTMS with 0.25Hz 60 pulses over the right SPL caused shorter IRT. There were no significant differences between IRTs for rTMS with 0.25Hz 120 pulses, 0.5Hz 120 pulses or 1Hz 120 pulses over the right SPL. Comparing these results with those of a previous study, we found that an rTMS condition with 60 pulses causes shorter IRT; 240 pulses causes longer IRT; and 120 pulses does not change IRT. Therefore, when applying rTMS over the right SPL, the IRT of perceptual reversal is primarily affected by the number of pulses.

Frequent video game players resist perceptual interference.

PubMed

Berard, Aaron V; Cain, Matthew S; Watanabe, Takeo; Sasaki, Yuka

2015-01-01

Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT), a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning.

Pupil size tracks perceptual content and surprise.

PubMed

Kloosterman, Niels A; Meindertsma, Thomas; van Loon, Anouk M; Lamme, Victor A F; Bonneh, Yoram S; Donner, Tobias H

2015-04-01

Changes in pupil size at constant light levels reflect the activity of neuromodulatory brainstem centers that control global brain state. These endogenously driven pupil dynamics can be synchronized with cognitive acts. For example, the pupil dilates during the spontaneous switches of perception of a constant sensory input in bistable perceptual illusions. It is unknown whether this pupil dilation only indicates the occurrence of perceptual switches, or also their content. Here, we measured pupil diameter in human subjects reporting the subjective disappearance and re-appearance of a physically constant visual target surrounded by a moving pattern ('motion-induced blindness' illusion). We show that the pupil dilates during the perceptual switches in the illusion and a stimulus-evoked 'replay' of that illusion. Critically, the switch-related pupil dilation encodes perceptual content, with larger amplitude for disappearance than re-appearance. This difference in pupil response amplitude enables prediction of the type of report (disappearance vs. re-appearance) on individual switches (receiver-operating characteristic: 61%). The amplitude difference is independent of the relative durations of target-visible and target-invisible intervals and subjects' overt behavioral report of the perceptual switches. Further, we show that pupil dilation during the replay also scales with the level of surprise about the timing of switches, but there is no evidence for an interaction between the effects of surprise and perceptual content on the pupil response. Taken together, our results suggest that pupil-linked brain systems track both the content of, and surprise about, perceptual events. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Is Perceptual Priming Affected by Culture? A Study With German Middle-Class and Cameroonian Nso Farmer Children.

PubMed

Vöhringer, Isabel Aline; Poloczek, Sonja; Graf, Frauke; Lamm, Bettina; Teiser, Johanna; Fassbender, Ina; Freitag, Claudia; Suhrke, Janina; Teubert, Manuel; Keller, Heidi; Lohaus, Arnold; Schwarzer, Gudrun; Knopf, Monika

2015-01-01

The authors explored priming in children from different cultural environments with the aim to provide further evidence for the robustness of the priming effect. Perceptual priming was assessed by a picture fragment completion task in 3-year-old German middle-class and Cameroonian Nso farmer children. As expected, 3-year-olds from both highly diverging cultural contexts under study showed a priming effect, and, moreover, the effect was of comparable size in both cultural contexts. Hence, the children profited similarly from priming, which was supported by the nonsignificant interaction between cultural background and identification performance as well as the analysis of absolute difference scores. However, a culture-specific difference regarding the level of picture identification was found in that German middle-class children identified target as well as control pictures with less perceptual information than children in the Nso sample. Explanations for the cross-cultural demonstration of the priming effect as well as for the culturally diverging levels on which priming occurs are discussed.

Dutch modality exclusivity norms: Simulating perceptual modality in space.

PubMed

Speed, Laura J; Majid, Asifa

2017-12-01

Perceptual information is important for the meaning of nouns. We present modality exclusivity norms for 485 Dutch nouns rated on visual, auditory, haptic, gustatory, and olfactory associations. We found these nouns are highly multimodal. They were rated most dominant in vision, and least in olfaction. A factor analysis identified two main dimensions: one loaded strongly on olfaction and gustation (reflecting joint involvement in flavor), and a second loaded strongly on vision and touch (reflecting joint involvement in manipulable objects). In a second study, we validated the ratings with similarity judgments. As expected, words from the same dominant modality were rated more similar than words from different dominant modalities; but - more importantly - this effect was enhanced when word pairs had high modality strength ratings. We further demonstrated the utility of our ratings by investigating whether perceptual modalities are differentially experienced in space, in a third study. Nouns were categorized into their dominant modality and used in a lexical decision experiment where the spatial position of words was either in proximal or distal space. We found words dominant in olfaction were processed faster in proximal than distal space compared to the other modalities, suggesting olfactory information is mentally simulated as "close" to the body. Finally, we collected ratings of emotion (valence, dominance, and arousal) to assess its role in perceptual space simulation, but the valence did not explain the data. So, words are processed differently depending on their perceptual associations, and strength of association is captured by modality exclusivity ratings.

Turkish- and English-speaking children display sensitivity to perceptual context in the referring expressions they produce in speech and gesture

PubMed Central

Demir, Özlem Ece; So, Wing-Chee; Özyürek, Asli; Goldin-Meadow, Susan

2012-01-01

Speakers choose a particular expression based on many factors, including availability of the referent in the perceptual context. We examined whether, when expressing referents, monolingual English- and Turkish-speaking children: (1) are sensitive to perceptual context, (2) express this sensitivity in language-specific ways, and (3) use co-speech gestures to specify referents that are underspecified. We also explored the mechanisms underlying children’s sensitivity to perceptual context. Children described short vignettes to an experimenter under two conditions: The characters in the vignettes were present in the perceptual context (perceptual context); the characters were absent (no perceptual context). Children routinely used nouns in the no perceptual context condition, but shifted to pronouns (English-speaking children) or omitted arguments (Turkish-speaking children) in the perceptual context condition. Turkish-speaking children used underspecified referents more frequently than English-speaking children in the perceptual context condition; however, they compensated for the difference by using gesture to specify the forms. Gesture thus gives children learning structurally different languages a way to achieve comparable levels of specification while at the same time adhering to the referential expressions dictated by their language. PMID:22904588

Perceptual discrimination difficulty and familiarity in the Uncanny Valley: more like a “Happy Valley”

PubMed Central

Cheetham, Marcus; Suter, Pascal; Jancke, Lutz

2014-01-01

The Uncanny Valley Hypothesis (UVH) predicts that greater difficulty perceptually discriminating between categorically ambiguous human and humanlike characters (e.g., highly realistic robot) evokes negatively valenced (i.e., uncanny) affect. An ABX perceptual discrimination task and signal detection analysis was used to examine the profile of perceptual discrimination (PD) difficulty along the UVH' dimension of human likeness (DHL). This was represented using avatar-to-human morph continua. Rejecting the implicitly assumed profile of PD difficulty underlying the UVH' prediction, Experiment 1 showed that PD difficulty was reduced for categorically ambiguous faces but, notably, enhanced for human faces. Rejecting the UVH' predicted relationship between PD difficulty and negative affect (assessed in terms of the UVH' familiarity dimension), Experiment 2 demonstrated that greater PD difficulty correlates with more positively valenced affect. Critically, this effect was strongest for the ambiguous faces, suggesting a correlative relationship between PD difficulty and feelings of familiarity more consistent with the metaphor happy valley. This relationship is also consistent with a fluency amplification instead of the hitherto proposed hedonic fluency account of affect along the DHL. Experiment 3 found no evidence that the asymmetry in the profile of PD along the DHL is attributable to a differential processing bias (cf. other-race effect), i.e., processing avatars at a category level but human faces at an individual level. In conclusion, the present data for static faces show clear effects that, however, strongly challenge the UVH' implicitly assumed profile of PD difficulty along the DHL and the predicted relationship between this and feelings of familiarity. PMID:25477829

The role of perceptual load in inattentional blindness.

PubMed

Cartwright-Finch, Ula; Lavie, Nilli

2007-03-01

Perceptual load theory offers a resolution to the long-standing early vs. late selection debate over whether task-irrelevant stimuli are perceived, suggesting that irrelevant perception depends upon the perceptual load of task-relevant processing. However, previous evidence for this theory has relied on RTs and neuroimaging. Here we tested the effects of load on conscious perception using the "inattentional blindness" paradigm. As predicted by load theory, awareness of a task-irrelevant stimulus was significantly reduced by higher perceptual load (with increased numbers of search items, or a harder discrimination vs. detection task). These results demonstrate that conscious perception of task-irrelevant stimuli critically depends upon the level of task-relevant perceptual load rather than intentions or expectations, thus enhancing the resolution to the early vs. late selection debate offered by the perceptual load theory.

Divided attention disrupts perceptual encoding during speech recognition.

PubMed

Mattys, Sven L; Palmer, Shekeila D

2015-03-01

Performing a secondary task while listening to speech has a detrimental effect on speech processing, but the locus of the disruption within the speech system is poorly understood. Recent research has shown that cognitive load imposed by a concurrent visual task increases dependency on lexical knowledge during speech processing, but it does not affect lexical activation per se. This suggests that "lexical drift" under cognitive load occurs either as a post-lexical bias at the decisional level or as a secondary consequence of reduced perceptual sensitivity. This study aimed to adjudicate between these alternatives using a forced-choice task that required listeners to identify noise-degraded spoken words with or without the addition of a concurrent visual task. Adding cognitive load increased the likelihood that listeners would select a word acoustically similar to the target even though its frequency was lower than that of the target. Thus, there was no evidence that cognitive load led to a high-frequency response bias. Rather, cognitive load seems to disrupt sublexical encoding, possibly by impairing perceptual acuity at the auditory periphery.

Perceptual tools for quality-aware video networks

NASA Astrophysics Data System (ADS)

Bovik, A. C.

2014-01-01

Monitoring and controlling the quality of the viewing experience of videos transmitted over increasingly congested networks (especially wireless networks) is a pressing problem owing to rapid advances in video-centric mobile communication and display devices that are straining the capacity of the network infrastructure. New developments in automatic perceptual video quality models offer tools that have the potential to be used to perceptually optimize wireless video, leading to more efficient video data delivery and better received quality. In this talk I will review key perceptual principles that are, or could be used to create effective video quality prediction models, and leading quality prediction models that utilize these principles. The goal is to be able to monitor and perceptually optimize video networks by making them "quality-aware."

Greater perceptual sensitivity to happy facial expression.

PubMed

Maher, Stephen; Ekstrom, Tor; Chen, Yue

2014-01-01

Perception of subtle facial expressions is essential for social functioning; yet it is unclear if human perceptual sensitivities differ in detecting varying types of facial emotions. Evidence diverges as to whether salient negative versus positive emotions (such as sadness versus happiness) are preferentially processed. Here, we measured perceptual thresholds for the detection of four types of emotion in faces--happiness, fear, anger, and sadness--using psychophysical methods. We also evaluated the association of the perceptual performances with facial morphological changes between neutral and respective emotion types. Human observers were highly sensitive to happiness compared with the other emotional expressions. Further, this heightened perceptual sensitivity to happy expressions can be attributed largely to the emotion-induced morphological change of a particular facial feature (end-lip raise).

Attentional selection within and across hemispheres: implications for the perceptual load theory.

PubMed

Wei, Ping; Kang, Guanlan; Zhou, Xiaolin

2013-03-01

The perceptual load of a given task affects attentional selection, with the selection occurring earlier when the load is high and later when the load is low. Recent evidence suggests that local competitive interaction may underlie the perceptual load effect and determine to what extent a task-irrelevant distractor is processed. Here, we asked participants to search for a target bar among homogeneously oriented bars (the low load conditions) or heterogeneously oriented bars (the high load conditions) in the central display, while ignoring a congruent or incongruent flanker bar presented to the left or right side of the central display, or a bar presented at one of the six positions outer to the central display. Importantly, we differentiated conditions in which the target in the central display and the peripheral flanker was presented within the same hemifield or across different hemifields. Results showed a significant flanker effect for the low load condition, but not for the high load condition, when the target and the flanker were across hemifields. However, when the target and the flanker were presented within the same hemifield, there was no flanker effect for either low or high load conditions. These findings demonstrate that the ability to ignore the task-irrelevant distractor is affected by local competition within hemisphere and that the perceptual load theory needs to be supplemented with detailed analysis of cognitive processes and mechanisms underlying the consumption of attentional resources.

Audiovisual speech perception development at varying levels of perceptual processing.

PubMed

Lalonde, Kaylah; Holt, Rachael Frush

2016-04-01

This study used the auditory evaluation framework [Erber (1982). Auditory Training (Alexander Graham Bell Association, Washington, DC)] to characterize the influence of visual speech on audiovisual (AV) speech perception in adults and children at multiple levels of perceptual processing. Six- to eight-year-old children and adults completed auditory and AV speech perception tasks at three levels of perceptual processing (detection, discrimination, and recognition). The tasks differed in the level of perceptual processing required to complete them. Adults and children demonstrated visual speech influence at all levels of perceptual processing. Whereas children demonstrated the same visual speech influence at each level of perceptual processing, adults demonstrated greater visual speech influence on tasks requiring higher levels of perceptual processing. These results support previous research demonstrating multiple mechanisms of AV speech processing (general perceptual and speech-specific mechanisms) with independent maturational time courses. The results suggest that adults rely on both general perceptual mechanisms that apply to all levels of perceptual processing and speech-specific mechanisms that apply when making phonetic decisions and/or accessing the lexicon. Six- to eight-year-old children seem to rely only on general perceptual mechanisms across levels. As expected, developmental differences in AV benefit on this and other recognition tasks likely reflect immature speech-specific mechanisms and phonetic processing in children.

A Perceptual Repetition Blindness Effect

NASA Technical Reports Server (NTRS)

Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

1994-01-01

Before concluding Repetition Blindness is a perceptual phenomenon, alternative explanations based on memory retrieval problems and report bias must be rejected. Memory problems were minimized by requiring a judgment about only a single briefly displayed field. Bias and sensitivity effects were empirically measured with an ROC-curve analysis method based on confidence ratings. Results from five experiments support the hypothesis that Repetition Blindness can be a perceptual phenomenon.

Associative fear learning and perceptual discrimination: a perceptual pathway in the development of chronic pain.

PubMed

Zaman, Jonas; Vlaeyen, Johan W S; Van Oudenhove, Lukas; Wiech, Katja; Van Diest, Ilse

2015-04-01

Recent neuropsychological theories emphasize the influence of maladaptive learning and memory processes on pain perception. However, the precise relationship between these processes as well as the underlying mechanisms remain poorly understood; especially the role of perceptual discrimination and its modulation by associative fear learning has received little attention so far. Experimental work with exteroceptive stimuli consistently points to effects of fear learning on perceptual discrimination acuity. In addition, clinical observations have revealed that in individuals with chronic pain perceptual discrimination is impaired, and that tactile discrimination training reduces pain. Based on these findings, we present a theoretical model of which the central tenet is that associative fear learning contributes to the development of chronic pain through impaired interoceptive and proprioceptive discrimination acuity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Perceptual load influences selective attention across development.

PubMed

Couperus, Jane W

2011-09-01

Research suggests that visual selective attention develops across childhood. However, there is relatively little understanding of the neurological changes that accompany this development, particularly in the context of adult theories of selective attention, such as N. Lavie's (1995) perceptual load theory of attention. This study examined visual selective attention across development from 7 years of age to adulthood. Specifically, the author examined if changes in processing as a function of selective attention are similarly influenced by perceptual load across development. Participants were asked to complete a task at either low or high perceptual load while processing of an unattended probe stimulus was examined using event related potentials. Similar to adults, children and teens showed reduced processing of the unattended stimulus as perceptual load increased at the P1 visual component. However, although there were no qualitative differences in changes in processing, there were quantitative differences, with shorter P1 latencies in teens and adults compared with children, suggesting increases in the speed of processing across development. In addition, younger children did not need as high a perceptual load to achieve the same difference in performance between low and high perceptual load as adults. Thus, this study demonstrates that although there are developmental changes in visual selective attention, the mechanisms by which visual selective attention is achieved in children may share similarities with adults.

Is Statistical Learning Constrained by Lower Level Perceptual Organization?

PubMed Central

Emberson, Lauren L.; Liu, Ran; Zevin, Jason D.

2013-01-01

In order for statistical information to aid in complex developmental processes such as language acquisition, learning from higher-order statistics (e.g. across successive syllables in a speech stream to support segmentation) must be possible while perceptual abilities (e.g. speech categorization) are still developing. The current study examines how perceptual organization interacts with statistical learning. Adult participants were presented with multiple exemplars from novel, complex sound categories designed to reflect some of the spectral complexity and variability of speech. These categories were organized into sequential pairs and presented such that higher-order statistics, defined based on sound categories, could support stream segmentation. Perceptual similarity judgments and multi-dimensional scaling revealed that participants only perceived three perceptual clusters of sounds and thus did not distinguish the four experimenter-defined categories, creating a tension between lower level perceptual organization and higher-order statistical information. We examined whether the resulting pattern of learning is more consistent with statistical learning being “bottom-up,” constrained by the lower levels of organization, or “top-down,” such that higher-order statistical information of the stimulus stream takes priority over the perceptual organization, and perhaps influences perceptual organization. We consistently find evidence that learning is constrained by perceptual organization. Moreover, participants generalize their learning to novel sounds that occupy a similar perceptual space, suggesting that statistical learning occurs based on regions of or clusters in perceptual space. Overall, these results reveal a constraint on learning of sound sequences, such that statistical information is determined based on lower level organization. These findings have important implications for the role of statistical learning in language acquisition. PMID:23618755

Differential effect of visual masking in perceptual categorization.

PubMed

Hélie, Sébastien; Cousineau, Denis

2015-06-01

This article explores the visual information used to categorize stimuli drawn from a common stimulus space into verbal and nonverbal categories using 2 experiments. Experiment 1 explores the effect of target duration on verbal and nonverbal categorization using backward masking to interrupt visual processing. With categories equated for difficulty for long and short target durations, intermediate target duration shows an advantage for verbal categorization over nonverbal categorization. Experiment 2 tests whether the results of Experiment 1 can be explained by shorter target duration resulting in a smaller signal-to-noise ratio of the categorization stimulus. To test for this possibility, Experiment 2 used integration masking with the same stimuli, categories, and masks as Experiment 1 with a varying level of mask opacity. As predicted, low mask opacity yielded similar results to long target duration while high mask opacity yielded similar results to short target duration. Importantly, intermediate mask opacity produced an advantage for verbal categorization over nonverbal categorization, similar to intermediate target duration. These results suggest that verbal and nonverbal categorization are affected differently by manipulations affecting the signal-to-noise ratio of the stimulus, consistent with multiple-system theories of categorizations. The results further suggest that verbal categorization may be more digital (and more robust to low signal-to-noise ratio) while the information used in nonverbal categorization may be more analog (and less robust to lower signal-to-noise ratio). This article concludes with a discussion of how these new results affect the use of masking in perceptual categorization and multiple-system theories of perceptual category learning. (c) 2015 APA, all rights reserved).

Perceptual Plasticity for Auditory Object Recognition

PubMed Central

Heald, Shannon L. M.; Van Hedger, Stephen C.; Nusbaum, Howard C.

2017-01-01

In our auditory environment, we rarely experience the exact acoustic waveform twice. This is especially true for communicative signals that have meaning for listeners. In speech and music, the acoustic signal changes as a function of the talker (or instrument), speaking (or playing) rate, and room acoustics, to name a few factors. Yet, despite this acoustic variability, we are able to recognize a sentence or melody as the same across various kinds of acoustic inputs and determine meaning based on listening goals, expectations, context, and experience. The recognition process relates acoustic signals to prior experience despite variability in signal-relevant and signal-irrelevant acoustic properties, some of which could be considered as “noise” in service of a recognition goal. However, some acoustic variability, if systematic, is lawful and can be exploited by listeners to aid in recognition. Perceivable changes in systematic variability can herald a need for listeners to reorganize perception and reorient their attention to more immediately signal-relevant cues. This view is not incorporated currently in many extant theories of auditory perception, which traditionally reduce psychological or neural representations of perceptual objects and the processes that act on them to static entities. While this reduction is likely done for the sake of empirical tractability, such a reduction may seriously distort the perceptual process to be modeled. We argue that perceptual representations, as well as the processes underlying perception, are dynamically determined by an interaction between the uncertainty of the auditory signal and constraints of context. This suggests that the process of auditory recognition is highly context-dependent in that the identity of a given auditory object may be intrinsically tied to its preceding context. To argue for the flexible neural and psychological updating of sound-to-meaning mappings across speech and music, we draw upon examples

Perceptual grouping across eccentricity.

PubMed

Tannazzo, Teresa; Kurylo, Daniel D; Bukhari, Farhan

2014-10-01

Across the visual field, progressive differences exist in neural processing as well as perceptual abilities. Expansion of stimulus scale across eccentricity compensates for some basic visual capacities, but not for high-order functions. It was hypothesized that as with many higher-order functions, perceptual grouping ability should decline across eccentricity. To test this prediction, psychophysical measurements of grouping were made across eccentricity. Participants indicated the dominant grouping of dot grids in which grouping was based upon luminance, motion, orientation, or proximity. Across trials, the organization of stimuli was systematically decreased until perceived grouping became ambiguous. For all stimulus features, grouping ability remained relatively stable until 40°, beyond which thresholds significantly elevated. The pattern of change across eccentricity varied across stimulus feature, in which stimulus scale, dot size, or stimulus size interacted with eccentricity effects. These results demonstrate that perceptual grouping of such stimuli is not reliant upon foveal viewing, and suggest that selection of dominant grouping patterns from ambiguous displays operates similarly across much of the visual field. Copyright © 2014 Elsevier Ltd. All rights reserved.

The role of convexity in perceptual completion: beyond good continuation.

PubMed

Liu, Z; Jacobs, D W; Basri, R

1999-01-01

Since the seminal work of the Gestalt psychologists, there has been great interest in understanding what factors determine the perceptual organization of images. While the Gestaltists demonstrated the significance of grouping cues such as similarity, proximity and good continuation, it has not been well understood whether their catalog of grouping cues is complete--in part due to the paucity of effective methodologies for examining the significance of various grouping cues. We describe a novel, objective method to study perceptual grouping of planar regions separated by an occluder. We demonstrate that the stronger the grouping between two such regions, the harder it will be to resolve their relative stereoscopic depth. We use this new method to call into question many existing theories of perceptual completion (Ullman, S. (1976). Biological Cybernetics, 25, 1-6; Shashua, A., & Ullman, S. (1988). 2nd International Conference on Computer Vision (pp. 321-327); Parent, P., & Zucker, S. (1989). IEEE Transactions on Pattern Analysis and Machine Intelligence, 11, 823-839; Kellman, P. J., & Shipley, T. F. (1991). Cognitive psychology, Liveright, New York; Heitger, R., & von der Heydt, R. (1993). A computational model of neural contour processing, figure-ground segregation and illusory contours. In Internal Conference Computer Vision (pp. 32-40); Mumford, D. (1994). Algebraic geometry and its applications, Springer, New York; Williams, L. R., & Jacobs, D. W. (1997). Neural Computation, 9, 837-858) that are based on Gestalt grouping cues by demonstrating that convexity plays a strong role in perceptual completion. In some cases convexity dominates the effects of the well known Gestalt cue of good continuation. While convexity has been known to play a role in figure/ground segmentation (Rubin, 1927; Kanizsa & Gerbino, 1976), this is the first demonstration of its importance in perceptual completion.

Exogenous attention facilitates location transfer of perceptual learning.

PubMed

Donovan, Ian; Szpiro, Sarit; Carrasco, Marisa

2015-01-01

Perceptual skills can be improved through practice on a perceptual task, even in adulthood. Visual perceptual learning is known to be mostly specific to the trained retinal location, which is considered as evidence of neural plasticity in retinotopic early visual cortex. Recent findings demonstrate that transfer of learning to untrained locations can occur under some specific training procedures. Here, we evaluated whether exogenous attention facilitates transfer of perceptual learning to untrained locations, both adjacent to the trained locations (Experiment 1) and distant from them (Experiment 2). The results reveal that attention facilitates transfer of perceptual learning to untrained locations in both experiments, and that this transfer occurs both within and across visual hemifields. These findings show that training with exogenous attention is a powerful regime that is able to overcome the major limitation of location specificity.

Exogenous attention facilitates location transfer of perceptual learning

PubMed Central

Donovan, Ian; Szpiro, Sarit; Carrasco, Marisa

2015-01-01

Perceptual skills can be improved through practice on a perceptual task, even in adulthood. Visual perceptual learning is known to be mostly specific to the trained retinal location, which is considered as evidence of neural plasticity in retinotopic early visual cortex. Recent findings demonstrate that transfer of learning to untrained locations can occur under some specific training procedures. Here, we evaluated whether exogenous attention facilitates transfer of perceptual learning to untrained locations, both adjacent to the trained locations (Experiment 1) and distant from them (Experiment 2). The results reveal that attention facilitates transfer of perceptual learning to untrained locations in both experiments, and that this transfer occurs both within and across visual hemifields. These findings show that training with exogenous attention is a powerful regime that is able to overcome the major limitation of location specificity. PMID:26426818

Comparative analysis of perceptual evaluation, acoustic analysis and indirect laryngoscopy for vocal assessment of a population with vocal complaint.

PubMed

Nemr, Kátia; Amar, Ali; Abrahão, Marcio; Leite, Grazielle Capatto de Almeida; Köhle, Juliana; Santos, Alexandra de O; Correa, Luiz Artur Costa

2005-01-01

As a result of technology evolution and development, methods of voice evaluation have changed both in medical and speech and language pathology practice. To relate the results of perceptual evaluation, acoustic analysis and medical evaluation in the diagnosis of vocal and/or laryngeal affections of the population with vocal complaint. Clinical prospective. 29 people that attended vocal health protection campaign were evaluated. They were submitted to perceptual evaluation (AFPA), acoustic analysis (AA), indirect laryngoscopy (LI) and telelaryngoscopy (TL). Correlations between medical and speech language pathology evaluation methods were established, verifying possible statistical signification with the application of Fischer Exact Test. There were statistically significant results in the correlation between AFPA and LI, AFPA and TL, LI and TL. This research study conducted in a vocal health protection campaign presented correlations between speech language pathology evaluation and perceptual evaluation and clinical evaluation, as well as between vocal affection and/or laryngeal medical exams.

Factors Affecting Tocopherol Concentrations in Soybean Seeds.

PubMed

Carrera, Constanza S; Seguin, Philippe

2016-12-21

Soybean seeds contain several health-beneficial compounds, including tocopherols, which are used by the nutraceutical and functional food industries. Soybean tocopherol concentrations are, however, highly variable. Large differences observed in tocopherol concentrations among soybean genotypes together with the relatively simple biosynthetic pathway involving few genes support the feasibility of selecting for high-tocopherol soybean. Tocopherol concentrations are also highly influenced by environmental factors and field management. Temperature during seed filling and soil moisture appear to be the main factors affecting tocopherol concentrations; other factors such as soil fertility and solar radiation also affect concentrations and composition. Field management decisions including seeding date, row spacing, irrigation, and fertilization also affect tocopherols. Knowledge of factors affecting soybean tocopherols is essential to develop management strategies that will lead to the production of seeds with consistent target concentrations that will meet the needs of the nutraceutical and functional food industries.

Audiovisual speech perception development at varying levels of perceptual processing

PubMed Central

Lalonde, Kaylah; Holt, Rachael Frush

2016-01-01

This study used the auditory evaluation framework [Erber (1982). Auditory Training (Alexander Graham Bell Association, Washington, DC)] to characterize the influence of visual speech on audiovisual (AV) speech perception in adults and children at multiple levels of perceptual processing. Six- to eight-year-old children and adults completed auditory and AV speech perception tasks at three levels of perceptual processing (detection, discrimination, and recognition). The tasks differed in the level of perceptual processing required to complete them. Adults and children demonstrated visual speech influence at all levels of perceptual processing. Whereas children demonstrated the same visual speech influence at each level of perceptual processing, adults demonstrated greater visual speech influence on tasks requiring higher levels of perceptual processing. These results support previous research demonstrating multiple mechanisms of AV speech processing (general perceptual and speech-specific mechanisms) with independent maturational time courses. The results suggest that adults rely on both general perceptual mechanisms that apply to all levels of perceptual processing and speech-specific mechanisms that apply when making phonetic decisions and/or accessing the lexicon. Six- to eight-year-old children seem to rely only on general perceptual mechanisms across levels. As expected, developmental differences in AV benefit on this and other recognition tasks likely reflect immature speech-specific mechanisms and phonetic processing in children. PMID:27106318

Web-based Factors Affecting Online Purchasing Behaviour

NASA Astrophysics Data System (ADS)

Ariff, Mohd Shoki Md; Sze Yan, Ng; Zakuan, Norhayati; Zaidi Bahari, Ahamad; Jusoh, Ahmad

2013-06-01

The growing use of internet and online purchasing among young consumers in Malaysia provides a huge prospect in e-commerce market, specifically for B2C segment. In this market, if E-marketers know the web-based factors affecting online buyers' behaviour, and the effect of these factors on behaviour of online consumers, then they can develop their marketing strategies to convert potential customers into active one, while retaining existing online customers. Review of previous studies related to the online purchasing behaviour in B2C market has point out that the conceptualization and empirical validation of the online purchasing behaviour of Information and Communication Technology (ICT) literate users, or ICT professional, in Malaysia has not been clearly addressed. This paper focuses on (i) web-based factors which online buyers (ICT professional) keep in mind while shopping online; and (ii) the effect of web-based factors on online purchasing behaviour. Based on the extensive literature review, a conceptual framework of 24 items of five factors was constructed to determine web-based factors affecting online purchasing behaviour of ICT professional. Analysis of data was performed based on the 310 questionnaires, which were collected using a stratified random sampling method, from ICT undergraduate students in a public university in Malaysia. The Exploratory factor analysis performed showed that five factors affecting online purchase behaviour are Information Quality, Fulfilment/Reliability/Customer Service, Website Design, Quick and Details, and Privacy/Security. The result of Multiple Regression Analysis indicated that Information Quality, Quick and Details, and Privacy/Security affect positively online purchase behaviour. The results provide a usable model for measuring web-based factors affecting buyers' online purchase behaviour in B2C market, as well as for online shopping companies to focus on the factors that will increase customers' online purchase.

Revisiting the empirical case against perceptual modularity

PubMed Central

Masrour, Farid; Nirshberg, Gregory; Schon, Michael; Leardi, Jason; Barrett, Emily

2015-01-01

Some theorists hold that the human perceptual system has a component that receives input only from units lower in the perceptual hierarchy. This thesis, that we shall here refer to as the encapsulation thesis, has been at the center of a continuing debate for the past few decades. Those who deny the encapsulation thesis often rely on the large body of psychological findings that allegedly suggest that perception is influenced by factors such as the beliefs, desires, goals, and the expectations of the perceiver. Proponents of the encapsulation thesis, however, often argue that, when correctly interpreted, these psychological findings are compatible with the thesis. In our view, the debate over the significance and the correct interpretation of these psychological findings has reached an impasse. We hold that this impasse is due to the methodological limitations over psychophysical experiments, and it is very unlikely that such experiments, on their own, could yield results that would settle the debate. After defending this claim, we argue that integrating data from cognitive neuroscience resolves the debate in favor of those who deny the encapsulation thesis. PMID:26583001

[Perceptual sharpness metric for visible and infrared color fusion images].

PubMed

Gao, Shao-Shu; Jin, Wei-Qi; Wang, Xia; Wang, Ling-Xue; Luo, Yuan

2012-12-01

For visible and infrared color fusion images, objective sharpness assessment model is proposed to measure the clarity of detail and edge definition of the fusion image. Firstly, the contrast sensitivity functions (CSF) of the human visual system is used to reduce insensitive frequency components under certain viewing conditions. Secondly, perceptual contrast model, which takes human luminance masking effect into account, is proposed based on local band-limited contrast model. Finally, the perceptual contrast is calculated in the region of interest (contains image details and edges) in the fusion image to evaluate image perceptual sharpness. Experimental results show that the proposed perceptual sharpness metrics provides better predictions, which are more closely matched to human perceptual evaluations, than five existing sharpness (blur) metrics for color images. The proposed perceptual sharpness metrics can evaluate the perceptual sharpness for color fusion images effectively.

How does Learning Impact Development in Infancy? The Case of Perceptual Organization

PubMed Central

Bhatt, Ramesh S.; Quinn, Paul C.

2011-01-01

Pattern perception and organization are critical functions of the visual cognition system. Many organizational processes are available early in life, such that infants as young 3 months of age are able to readily utilize a variety of cues to organize visual patterns. However, other processes are not readily evident in young infants, and their development involves perceptual learning. We describe a theoretical framework that addresses perceptual learning in infancy and the manner in which it affects visual organization and development. It identifies five kinds of experiences that induce learning, and suggests that they work via attentional and unitization mechanisms to modify visual organization. In addition, the framework proposes that this kind of learning is abstract, domain general, functional at different ages in a qualitatively similar manner, and has a long-term impact on development through a memory reactivation process. Although most models of development assume that experience is fundamental to development, very little is actually known about the process by which experience affects development. The proposed framework is an attempt to account for this process in the domain of perception. PMID:21572570

The effects of attention on perceptual implicit memory.

PubMed

Rajaram, S; Srinivas, K; Travers, S

2001-10-01

Reports on the effects of dividing attention at study on subsequent perceptual priming suggest that perceptual priming is generally unaffected by attentional manipulations as long as word identity is processed. We tested this hypothesis in three experiments by using the implicit word fragment completion and word stem completion tasks. Division of attention was instantiated with the Stroop task in order to ensure the processing of word identity even when the participant's attention was directed to a stimulus attribute other than the word itself. Under these conditions, we found that even though perceptual priming was significant, it was significantly reduced in magnitude. A stem cued recall test in Experiment 2 confirmed a more deleterious effect of divided attention on explicit memory. Taken together, our findings delineate the relative contributions of perceptual analysis and attentional processes in mediating perceptual priming on two ubiquitously used tasks of word fragment completion and word stem completion.

Zooming in on the cause of the perceptual load effect in the go/no-go paradigm.

PubMed

Chen, Zhe; Cave, Kyle R

2016-08-01

Perceptual load theory (Lavie, 2005) claims that attentional capacity that is not used for the current task is allocated to irrelevant distractors. It predicts that if the attentional demands of the current task are high, distractor interference will be low. One particularly powerful demonstration of perceptual load effects on distractor processing relies on a go/no-go cue that is interpreted by either simple feature detection or feature conjunction (Lavie, 1995). However, a possible alternative interpretation of these effects is that the differential degree of distractor processing is caused by how broadly attention is allocated (attentional zoom) rather than to perceptual load. In 4 experiments, we show that when stimuli are arranged to equalize the extent of spatial attention across conditions, distractor interference varies little whether cues are defined by a simple feature or a conjunction, and that the typical perceptual load effect emerges only when attentional zoom can covary with perceptual load. These results suggest that attentional zoom can account for the differential degree of distractor processing traditionally attributed to perceptual load in the go/no-go paradigm. They also provide new insight into how different factors interact to control distractor interference. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The objects of visuospatial short-term memory: Perceptual organization and change detection.

PubMed

Nikolova, Atanaska; Macken, Bill

2016-01-01

We used a colour change-detection paradigm where participants were required to remember colours of six equally spaced circles. Items were superimposed on a background so as to perceptually group them within (a) an intact ring-shaped object, (b) a physically segmented but perceptually completed ring-shaped object, or (c) a corresponding background segmented into three arc-shaped objects. A nonpredictive cue at the location of one of the circles was followed by the memory items, which in turn were followed by a test display containing a probe indicating the circle to be judged same/different. Reaction times for correct responses revealed a same-object advantage; correct responses were faster to probes on the same object as the cue than to equidistant probes on a segmented object. This same-object advantage was identical for physically and perceptually completed objects, but was only evident in reaction times, and not in accuracy measures. Not only, therefore, is it important to consider object-level perceptual organization of stimulus elements when assessing the influence of a range of factors (e.g., number and complexity of elements) in visuospatial short-term memory, but a more detailed picture of the structure of information in memory may be revealed by measuring speed as well as accuracy.

The objects of visuospatial short-term memory: Perceptual organization and change detection

PubMed Central

Nikolova, Atanaska; Macken, Bill

2016-01-01

We used a colour change-detection paradigm where participants were required to remember colours of six equally spaced circles. Items were superimposed on a background so as to perceptually group them within (a) an intact ring-shaped object, (b) a physically segmented but perceptually completed ring-shaped object, or (c) a corresponding background segmented into three arc-shaped objects. A nonpredictive cue at the location of one of the circles was followed by the memory items, which in turn were followed by a test display containing a probe indicating the circle to be judged same/different. Reaction times for correct responses revealed a same-object advantage; correct responses were faster to probes on the same object as the cue than to equidistant probes on a segmented object. This same-object advantage was identical for physically and perceptually completed objects, but was only evident in reaction times, and not in accuracy measures. Not only, therefore, is it important to consider object-level perceptual organization of stimulus elements when assessing the influence of a range of factors (e.g., number and complexity of elements) in visuospatial short-term memory, but a more detailed picture of the structure of information in memory may be revealed by measuring speed as well as accuracy. PMID:26286369

Advanced Computer Image Generation Techniques Exploiting Perceptual Characteristics

DTIC Science & Technology

1981-08-01

the capabilities/limitations of the human visual perceptual processing system and improve the training effectiveness of visual simulation systems...Myron Braunstein of the University of California at Irvine performed all the work in the perceptual area. Mr. Timothy A. Zimmerlin contributed the... work . Thus, while some areas are related, each is resolved independently in order to focus on the basic perceptual limitation. In addition, the

Perceptual Space of Superimposed Dual-Frequency Vibrations in the Hands.

PubMed

Hwang, Inwook; Seo, Jeongil; Choi, Seungmoon

2017-01-01

The use of distinguishable complex vibrations that have multiple spectral components can improve the transfer of information by vibrotactile interfaces. We investigated the qualitative characteristics of dual-frequency vibrations as the simplest complex vibrations compared to single-frequency vibrations. Two psychophysical experiments were conducted to elucidate the perceptual characteristics of these vibrations by measuring the perceptual distances among single-frequency and dual-frequency vibrations. The perceptual distances of dual-frequency vibrations between their two frequency components along their relative intensity ratio were measured in Experiment I. The estimated perceptual spaces for three frequency conditions showed non-linear perceptual differences between the dual-frequency and single-frequency vibrations. A perceptual space was estimated from the measured perceptual distances among ten dual-frequency compositions and five single-frequency vibrations in Experiment II. The effect of the component frequency and the frequency ratio was revealed in the perceptual space. In a percept of dual-frequency vibration, the lower frequency component showed a dominant effect. Additionally, the perceptual difference among single-frequency and dual-frequency vibrations were increased with a low relative difference between two frequencies of a dual-frequency vibration. These results are expected to provide a fundamental understanding about the perception of complex vibrations to enrich the transfer of information using vibrotactile stimuli.

Perceptual Contrast Enhancement with Dynamic Range Adjustment

PubMed Central

Zhang, Hong; Li, Yuecheng; Chen, Hao; Yuan, Ding; Sun, Mingui

2013-01-01

Recent years, although great efforts have been made to improve its performance, few Histogram equalization (HE) methods take human visual perception (HVP) into account explicitly. The human visual system (HVS) is more sensitive to edges than brightness. This paper proposes to take use of this nature intuitively and develops a perceptual contrast enhancement approach with dynamic range adjustment through histogram modification. The use of perceptual contrast connects the image enhancement problem with the HVS. To pre-condition the input image before the HE procedure is implemented, a perceptual contrast map (PCM) is constructed based on the modified Difference of Gaussian (DOG) algorithm. As a result, the contrast of the image is sharpened and high frequency noise is suppressed. A modified Clipped Histogram Equalization (CHE) is also developed which improves visual quality by automatically detecting the dynamic range of the image with improved perceptual contrast. Experimental results show that the new HE algorithm outperforms several state-of-the-art algorithms in improving perceptual contrast and enhancing details. In addition, the new algorithm is simple to implement, making it suitable for real-time applications. PMID:24339452

Perceptual load interacts with stimulus processing across sensory modalities.

PubMed

Klemen, J; Büchel, C; Rose, M

2009-06-01

According to perceptual load theory, processing of task-irrelevant stimuli is limited by the perceptual load of a parallel attended task if both the task and the irrelevant stimuli are presented to the same sensory modality. However, it remains a matter of debate whether the same principles apply to cross-sensory perceptual load and, more generally, what form cross-sensory attentional modulation in early perceptual areas takes in humans. Here we addressed these questions using functional magnetic resonance imaging. Participants undertook an auditory one-back working memory task of low or high perceptual load, while concurrently viewing task-irrelevant images at one of three object visibility levels. The processing of the visual and auditory stimuli was measured in the lateral occipital cortex (LOC) and auditory cortex (AC), respectively. Cross-sensory interference with sensory processing was observed in both the LOC and AC, in accordance with previous results of unisensory perceptual load studies. The present neuroimaging results therefore warrant the extension of perceptual load theory from a unisensory to a cross-sensory context: a validation of this cross-sensory interference effect through behavioural measures would consolidate the findings.

Object similarity affects the perceptual strategy underlying invariant visual object recognition in rats

PubMed Central

Rosselli, Federica B.; Alemi, Alireza; Ansuini, Alessio; Zoccolan, Davide

2015-01-01

In recent years, a number of studies have explored the possible use of rats as models of high-level visual functions. One central question at the root of such an investigation is to understand whether rat object vision relies on the processing of visual shape features or, rather, on lower-order image properties (e.g., overall brightness). In a recent study, we have shown that rats are capable of extracting multiple features of an object that are diagnostic of its identity, at least when those features are, structure-wise, distinct enough to be parsed by the rat visual system. In the present study, we have assessed the impact of object structure on rat perceptual strategy. We trained rats to discriminate between two structurally similar objects, and compared their recognition strategies with those reported in our previous study. We found that, under conditions of lower stimulus discriminability, rat visual discrimination strategy becomes more view-dependent and subject-dependent. Rats were still able to recognize the target objects, in a way that was largely tolerant (i.e., invariant) to object transformation; however, the larger structural and pixel-wise similarity affected the way objects were processed. Compared to the findings of our previous study, the patterns of diagnostic features were: (i) smaller and more scattered; (ii) only partially preserved across object views; and (iii) only partially reproducible across rats. On the other hand, rats were still found to adopt a multi-featural processing strategy and to make use of part of the optimal discriminatory information afforded by the two objects. Our findings suggest that, as in humans, rat invariant recognition can flexibly rely on either view-invariant representations of distinctive object features or view-specific object representations, acquired through learning. PMID:25814936

Accurate expectancies diminish perceptual distraction during visual search

PubMed Central

Sy, Jocelyn L.; Guerin, Scott A.; Stegman, Anna; Giesbrecht, Barry

2014-01-01

The load theory of visual attention proposes that efficient selective perceptual processing of task-relevant information during search is determined automatically by the perceptual demands of the display. If the perceptual demands required to process task-relevant information are not enough to consume all available capacity, then the remaining capacity automatically and exhaustively “spills-over” to task-irrelevant information. The spill-over of perceptual processing capacity increases the likelihood that task-irrelevant information will impair performance. In two visual search experiments, we tested the automaticity of the allocation of perceptual processing resources by measuring the extent to which the processing of task-irrelevant distracting stimuli was modulated by both perceptual load and top-down expectations using behavior, functional magnetic resonance imaging, and electrophysiology. Expectations were generated using a trial-by-trial cue that provided information about the likely load of the upcoming visual search task. When the cues were valid, behavioral interference was eliminated and the influence of load on frontoparietal and visual cortical responses was attenuated relative to when the cues were invalid. In conditions in which task-irrelevant information interfered with performance and modulated visual activity, individual differences in mean blood oxygenation level dependent responses measured from the left intraparietal sulcus were negatively correlated with individual differences in the severity of distraction. These results are consistent with the interpretation that a top-down biasing mechanism interacts with perceptual load to support filtering of task-irrelevant information. PMID:24904374

Perceptual memory drives learning of retinotopic biases for bistable stimuli.

PubMed

Murphy, Aidan P; Leopold, David A; Welchman, Andrew E

2014-01-01

The visual system exploits past experience at multiple timescales to resolve perceptual ambiguity in the retinal image. For example, perception of a bistable stimulus can be biased toward one interpretation over another when preceded by a brief presentation of a disambiguated version of the stimulus (positive priming) or through intermittent presentations of the ambiguous stimulus (stabilization). Similarly, prior presentations of unambiguous stimuli can be used to explicitly "train" a long-lasting association between a percept and a retinal location (perceptual association). These phenonema have typically been regarded as independent processes, with short-term biases attributed to perceptual memory and longer-term biases described as associative learning. Here we tested for interactions between these two forms of experience-dependent perceptual bias and demonstrate that short-term processes strongly influence long-term outcomes. We first demonstrate that the establishment of long-term perceptual contingencies does not require explicit training by unambiguous stimuli, but can arise spontaneously during the periodic presentation of brief, ambiguous stimuli. Using rotating Necker cube stimuli, we observed enduring, retinotopically specific perceptual biases that were expressed from the outset and remained stable for up to 40 min, consistent with the known phenomenon of perceptual stabilization. Further, bias was undiminished after a break period of 5 min, but was readily reset by interposed periods of continuous, as opposed to periodic, ambiguous presentation. Taken together, the results demonstrate that perceptual biases can arise naturally and may principally reflect the brain's tendency to favor recent perceptual interpretation at a given retinal location. Further, they suggest that an association between retinal location and perceptual state, rather than a physical stimulus, is sufficient to generate long-term biases in perceptual organization.

Nicotine facilitates memory consolidation in perceptual learning.

PubMed

Beer, Anton L; Vartak, Devavrat; Greenlee, Mark W

2013-01-01

Perceptual learning is a special type of non-declarative learning that involves experience-dependent plasticity in sensory cortices. The cholinergic system is known to modulate declarative learning. In particular, reduced levels or efficacy of the neurotransmitter acetylcholine were found to facilitate declarative memory consolidation. However, little is known about the role of the cholinergic system in memory consolidation of non-declarative learning. Here we compared two groups of non-smoking men who learned a visual texture discrimination task (TDT). One group received chewing tobacco containing nicotine for 1 h directly following the TDT training. The other group received a similar tasting control substance without nicotine. Electroencephalographic recordings during substance consumption showed reduced alpha activity and P300 latencies in the nicotine group compared to the control group. When re-tested on the TDT the following day, both groups responded more accurately and more rapidly than during training. These improvements were specific to the retinal location and orientation of the texture elements of the TDT suggesting that learning involved early visual cortex. A group comparison showed that learning effects were more pronounced in the nicotine group than in the control group. These findings suggest that oral consumption of nicotine enhances the efficacy of nicotinic acetylcholine receptors. Our findings further suggest that enhanced efficacy of the cholinergic system facilitates memory consolidation in perceptual learning (and possibly other types of non-declarative learning). In that regard acetylcholine seems to affect consolidation processes in perceptual learning in a different manner than in declarative learning. Alternatively, our findings might reflect dose-dependent cholinergic modulation of memory consolidation. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of Category-Specific Costs on Neural Systems for Perceptual Decision-Making

PubMed Central

Whiteley, Louise; Hulme, Oliver J.; Sahani, Maneesh; Dolan, Raymond J.

2010-01-01

Perceptual judgments are often biased by prospective losses, leading to changes in decision criteria. Little is known about how and where sensory evidence and cost information interact in the brain to influence perceptual categorization. Here we show that prospective losses systematically bias the perception of noisy face-house images. Asymmetries in category-specific cost were associated with enhanced blood-oxygen-level-dependent signal in a frontoparietal network. We observed selective activation of parahippocampal gyrus for changes in category-specific cost in keeping with the hypothesis that loss functions enact a particular task set that is communicated to visual regions. Across subjects, greater shifts in decision criteria were associated with greater activation of the anterior cingulate cortex (ACC). Our results support a hypothesis that costs bias an intermediate representation between perception and action, expressed via general effects on frontal cortex, and selective effects on extrastriate cortex. These findings indicate that asymmetric costs may affect a neural implementation of perceptual decision making in a similar manner to changes in category expectation, constituting a step toward accounting for how prospective losses are flexibly integrated with sensory evidence in the brain. PMID:20357071

Effects of category-specific costs on neural systems for perceptual decision-making.

PubMed

Fleming, Stephen M; Whiteley, Louise; Hulme, Oliver J; Sahani, Maneesh; Dolan, Raymond J

2010-06-01

Perceptual judgments are often biased by prospective losses, leading to changes in decision criteria. Little is known about how and where sensory evidence and cost information interact in the brain to influence perceptual categorization. Here we show that prospective losses systematically bias the perception of noisy face-house images. Asymmetries in category-specific cost were associated with enhanced blood-oxygen-level-dependent signal in a frontoparietal network. We observed selective activation of parahippocampal gyrus for changes in category-specific cost in keeping with the hypothesis that loss functions enact a particular task set that is communicated to visual regions. Across subjects, greater shifts in decision criteria were associated with greater activation of the anterior cingulate cortex (ACC). Our results support a hypothesis that costs bias an intermediate representation between perception and action, expressed via general effects on frontal cortex, and selective effects on extrastriate cortex. These findings indicate that asymmetric costs may affect a neural implementation of perceptual decision making in a similar manner to changes in category expectation, constituting a step toward accounting for how prospective losses are flexibly integrated with sensory evidence in the brain.

Effects of deep brain stimulation of the subthalamic nucleus on perceptual decision making.

PubMed

Zaehle, Tino; Wagenbreth, Caroline; Voges, Jürgen; Heinze, Hans-Jochen; Galazky, Imke

2017-02-20

When faced with difficult decisions, people prefer to stay with the default. This status quo bias often leads to suboptimal choice behavior. Neurophysiological evidence suggests a pivot role of the Subthalamic Nucleus (STN) for overcoming such status quo bias in difficult decisions, but causal evidence is lacking. The present study investigated whether subthalamic deep brain stimulation (DBS) in patients with Parkinson's disease (PD) influences the status quo bias. Eighteen PD patients treated with STN-DBS performed a difficult perceptual decision task incorporating intrinsic status quo option. Patients were tested with (ON) and without (OFF) active STN stimulation. Our results show that DBS of the STN affected perceptual decision making in PD patients depending on the difficulty of decision. STN-DBS improved difficult perceptual decisions due to a selective increase in accuracy (hit rate) that was independent of response bias (no effect on false alarm rate). Furthermore, STN-DBS impacted status quo bias as a function of baseline impulsivity. In impulsive patients, STN-DBS increased the default bias, whereas in less impulsive PD patients, DBS of the STN reduced the status quo bias. In line with our hypothesis, STN-DBS selectively affected the tendency to stick with the default option on difficult decisions, and promoted increased decision accuracy. Moreover, we demonstrate the impact of baseline cognitive abilities on DBS-related performance changes in PD patients. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Independence of long-term contextual memory and short-term perceptual hypotheses: Evidence from contextual cueing of interrupted search.

PubMed

Schlagbauer, Bernhard; Mink, Maurice; Müller, Hermann J; Geyer, Thomas

2017-02-01

Observers are able to resume an interrupted search trial faster relative to responding to a new, unseen display. This finding of rapid resumption is attributed to short-term perceptual hypotheses generated on the current look and confirmed upon subsequent looks at the same display. It has been suggested that the contents of perceptual hypotheses are similar to those of other forms of memory acquired long-term through repeated exposure to the same search displays over the course of several trials, that is, the memory supporting "contextual cueing." In three experiments, we investigated the relationship between short-term perceptual hypotheses and long-term contextual memory. The results indicated that long-term, contextual memory of repeated displays neither affected the generation nor the confirmation of short-term perceptual hypotheses for these displays. Furthermore, the analysis of eye movements suggests that long-term memory provides an initial benefit in guiding attention to the target, whereas in subsequent looks guidance is entirely based on short-term perceptual hypotheses. Overall, the results reveal a picture of both long- and short-term memory contributing to reliable performance gains in interrupted search, while exerting their effects in an independent manner.

Perceptual Differences between Hippies and College Students

ERIC Educational Resources Information Center

Brothers, Robert; Gaines, Rosslyn

1973-01-01

Perceptual differences were investigated between 50 college students who were non-drug users and 50 hippies who used LSD. The major hypothesis predicted was that hippies would score differently from college students in a specific direction on each of the perceptual tasks. (Author)

The effects of acute stress and perceptual load on distractor interference.

PubMed

Sato, Hirotsune; Takenaka, Ippei; Kawahara, Jun I

2012-01-01

Selective attention can be improved under conditions in which a high perceptual load is assumed to exhaust cognitive resources, leaving scarce resources for distractor processing. The present study examined whether perceptual load and acute stress share common attentional resources by manipulating perceptual and stress loads. Participants identified a target within an array of nontargets that were flanked by compatible or incompatible distractors. Attentional selectivity was measured by longer reaction times in response to the incompatible than to the compatible distractors. Participants in the stress group participated in a speech test that increased anxiety and threatened self-esteem. The effect of perceptual load interacted with the stress manipulation in that participants in the control group demonstrated an interference effect under the low perceptual load condition, whereas such interference disappeared under the high perceptual load condition. Importantly, the stress group showed virtually no interference under the low perceptual load condition, whereas substantial interference occurred under the high perceptual load condition. These results suggest that perceptual and stress related demands consume the same attentional resources.

Perceptual Load-Dependent Neural Correlates of Distractor Interference Inhibition

PubMed Central

Xu, Jiansong; Monterosso, John; Kober, Hedy; Balodis, Iris M.; Potenza, Marc N.

2011-01-01

Background The load theory of selective attention hypothesizes that distractor interference is suppressed after perceptual processing (i.e., in the later stage of central processing) at low perceptual load of the central task, but in the early stage of perceptual processing at high perceptual load. Consistently, studies on the neural correlates of attention have found a smaller distractor-related activation in the sensory cortex at high relative to low perceptual load. However, it is not clear whether the distractor-related activation in brain regions linked to later stages of central processing (e.g., in the frontostriatal circuits) is also smaller at high rather than low perceptual load, as might be predicted based on the load theory. Methodology/Principal Findings We studied 24 healthy participants using functional magnetic resonance imaging (fMRI) during a visual target identification task with two perceptual loads (low vs. high). Participants showed distractor-related increases in activation in the midbrain, striatum, occipital and medial and lateral prefrontal cortices at low load, but distractor-related decreases in activation in the midbrain ventral tegmental area and substantia nigra (VTA/SN), striatum, thalamus, and extensive sensory cortices at high load. Conclusions Multiple levels of central processing involving midbrain and frontostriatal circuits participate in suppressing distractor interference at either low or high perceptual load. For suppressing distractor interference, the processing of sensory inputs in both early and late stages of central processing are enhanced at low load but inhibited at high load. PMID:21267080

Perceptual load-dependent neural correlates of distractor interference inhibition.

PubMed

Xu, Jiansong; Monterosso, John; Kober, Hedy; Balodis, Iris M; Potenza, Marc N

2011-01-18

The load theory of selective attention hypothesizes that distractor interference is suppressed after perceptual processing (i.e., in the later stage of central processing) at low perceptual load of the central task, but in the early stage of perceptual processing at high perceptual load. Consistently, studies on the neural correlates of attention have found a smaller distractor-related activation in the sensory cortex at high relative to low perceptual load. However, it is not clear whether the distractor-related activation in brain regions linked to later stages of central processing (e.g., in the frontostriatal circuits) is also smaller at high rather than low perceptual load, as might be predicted based on the load theory. We studied 24 healthy participants using functional magnetic resonance imaging (fMRI) during a visual target identification task with two perceptual loads (low vs. high). Participants showed distractor-related increases in activation in the midbrain, striatum, occipital and medial and lateral prefrontal cortices at low load, but distractor-related decreases in activation in the midbrain ventral tegmental area and substantia nigra (VTA/SN), striatum, thalamus, and extensive sensory cortices at high load. Multiple levels of central processing involving midbrain and frontostriatal circuits participate in suppressing distractor interference at either low or high perceptual load. For suppressing distractor interference, the processing of sensory inputs in both early and late stages of central processing are enhanced at low load but inhibited at high load.

Factors Affecting Wound Healing

PubMed Central

Guo, S.; DiPietro, L.A.

2010-01-01

Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutaneous wound healing and the potential cellular and/or molecular mechanisms involved. The factors discussed include oxygenation, infection, age and sex hormones, stress, diabetes, obesity, medications, alcoholism, smoking, and nutrition. A better understanding of the influence of these factors on repair may lead to therapeutics that improve wound healing and resolve impaired wounds. PMID:20139336

Factors affecting wound healing.

PubMed

Guo, S; Dipietro, L A

2010-03-01

Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutaneous wound healing and the potential cellular and/or molecular mechanisms involved. The factors discussed include oxygenation, infection, age and sex hormones, stress, diabetes, obesity, medications, alcoholism, smoking, and nutrition. A better understanding of the influence of these factors on repair may lead to therapeutics that improve wound healing and resolve impaired wounds.

Further Boundary Conditions for the Effects of Perceptual Disfluency on Judgments of Learning

ERIC Educational Resources Information Center

Magreehan, Debbie A.; Serra, Michael J.; Schwartz, Neil H.; Narciss, Susanne

2016-01-01

The experience of fluency while learning might bias students' metacognitive judgments of learning (JOLs) and impair the efficacy of their study behaviors. In the present experiments, we examined whether perceptual fluency affects JOLs (1) when people only experience one level of fluency, (2) when item relatedness is also available as a cue, and…

Perceptual congruency of audio-visual speech affects ventriloquism with bilateral visual stimuli.

PubMed

Kanaya, Shoko; Yokosawa, Kazuhiko

2011-02-01

Many studies on multisensory processes have focused on performance in simplified experimental situations, with a single stimulus in each sensory modality. However, these results cannot necessarily be applied to explain our perceptual behavior in natural scenes where various signals exist within one sensory modality. We investigated the role of audio-visual syllable congruency on participants' auditory localization bias or the ventriloquism effect using spoken utterances and two videos of a talking face. Salience of facial movements was also manipulated. Results indicated that more salient visual utterances attracted participants' auditory localization. Congruent pairing of audio-visual utterances elicited greater localization bias than incongruent pairing, while previous studies have reported little dependency on the reality of stimuli in ventriloquism. Moreover, audio-visual illusory congruency, owing to the McGurk effect, caused substantial visual interference on auditory localization. Multisensory performance appears more flexible and adaptive in this complex environment than in previous studies.

Auditory-Perceptual Learning Improves Speech Motor Adaptation in Children

PubMed Central

Shiller, Douglas M.; Rochon, Marie-Lyne

2015-01-01

Auditory feedback plays an important role in children’s speech development by providing the child with information about speech outcomes that is used to learn and fine-tune speech motor plans. The use of auditory feedback in speech motor learning has been extensively studied in adults by examining oral motor responses to manipulations of auditory feedback during speech production. Children are also capable of adapting speech motor patterns to perceived changes in auditory feedback, however it is not known whether their capacity for motor learning is limited by immature auditory-perceptual abilities. Here, the link between speech perceptual ability and the capacity for motor learning was explored in two groups of 5–7-year-old children who underwent a period of auditory perceptual training followed by tests of speech motor adaptation to altered auditory feedback. One group received perceptual training on a speech acoustic property relevant to the motor task while a control group received perceptual training on an irrelevant speech contrast. Learned perceptual improvements led to an enhancement in speech motor adaptation (proportional to the perceptual change) only for the experimental group. The results indicate that children’s ability to perceive relevant speech acoustic properties has a direct influence on their capacity for sensory-based speech motor adaptation. PMID:24842067

Perceptually-Based Adaptive JPEG Coding

NASA Technical Reports Server (NTRS)

Watson, Andrew B.; Rosenholtz, Ruth; Null, Cynthia H. (Technical Monitor)

1996-01-01

An extension to the JPEG standard (ISO/IEC DIS 10918-3) allows spatial adaptive coding of still images. As with baseline JPEG coding, one quantization matrix applies to an entire image channel, but in addition the user may specify a multiplier for each 8 x 8 block, which multiplies the quantization matrix, yielding the new matrix for the block. MPEG 1 and 2 use much the same scheme, except there the multiplier changes only on macroblock boundaries. We propose a method for perceptual optimization of the set of multipliers. We compute the perceptual error for each block based upon DCT quantization error adjusted according to contrast sensitivity, light adaptation, and contrast masking, and pick the set of multipliers which yield maximally flat perceptual error over the blocks of the image. We investigate the bitrate savings due to this adaptive coding scheme and the relative importance of the different sorts of masking on adaptive coding.

Auditory perceptual load: A review.

PubMed

Murphy, Sandra; Spence, Charles; Dalton, Polly

2017-09-01

Selective attention is a crucial mechanism in everyday life, allowing us to focus on a portion of incoming sensory information at the expense of other less relevant stimuli. The circumstances under which irrelevant stimuli are successfully ignored have been a topic of scientific interest for several decades now. Over the last 20 years, the perceptual load theory (e.g. Lavie, 1995) has provided one robust framework for understanding these effects within the visual modality. The suggestion is that successful selection depends on the perceptual demands imposed by the task-relevant information. However, less research has addressed the question of whether the same principles hold in audition and, to date, the existing literature provides a mixed picture. Here, we review the evidence for and against the applicability of perceptual load theory in hearing, concluding that this question still awaits resolution. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Perceptual and memorial contributions to developmental prosopagnosia.

PubMed

Ulrich, Philip I N; Wilkinson, David T; Ferguson, Heather J; Smith, Laura J; Bindemann, Markus; Johnston, Robert A; Schmalzl, Laura

2017-02-01

Developmental prosopagnosia (DP) is commonly associated with the failure to properly perceive individuating facial properties, notably those conveying configural or holistic content. While this may indicate that the primary impairment is perceptual, it is conceivable that some cases of DP are instead caused by a memory impairment, with any perceptual complaint merely allied rather than causal. To investigate this possibility, we administered a battery of face perception tasks to 11 individuals who reported that their face recognition difficulties disrupt daily activity and who also performed poorly on two formal tests of face recognition. Group statistics identified, relative to age- and gender-matched controls, difficulties in apprehending global-local relations and the holistic properties of faces, and in matching across viewpoints, but these were mild in nature and were not consistently evident at the level of individual participants. Six of the 11 individuals failed to show any evidence of perceptual impairment. In the remaining five individuals, no single perceptual deficit, or combination of deficits, was necessary or sufficient for poor recognition performance. These data suggest that some cases of DP are better explained by a memorial rather than perceptual deficit, and highlight the relevance of the apperceptive/associative distinction more commonly applied to the allied syndrome of acquired prosopagnosia.

The role of perceptual load in object recognition.

PubMed

Lavie, Nilli; Lin, Zhicheng; Zokaei, Nahid; Thoma, Volker

2009-10-01

Predictions from perceptual load theory (Lavie, 1995, 2005) regarding object recognition across the same or different viewpoints were tested. Results showed that high perceptual load reduces distracter recognition levels despite always presenting distracter objects from the same view. They also showed that the levels of distracter recognition were unaffected by a change in the distracter object view under conditions of low perceptual load. These results were found both with repetition priming measures of distracter recognition and with performance on a surprise recognition memory test. The results support load theory proposals that distracter recognition critically depends on the level of perceptual load. The implications for the role of attention in object recognition theories are discussed. PsycINFO Database Record (c) 2009 APA, all rights reserved.

Factors Affecting Sign Retroreflectivity : final report.

DOT National Transportation Integrated Search

2001-01-01

This study was undertaken to better understand the factors that may affect road sign retroreflectivity, specifically age and physical orientation. A better understanding of these factors could provide guidance to ODOT in managing its inventory of roa...

Enhanced Perceptual Processing of Speech in Autism

ERIC Educational Resources Information Center

Jarvinen-Pasley, Anna; Wallace, Gregory L.; Ramus, Franck; Happe, Francesca; Heaton, Pamela

2008-01-01

Theories of autism have proposed that a bias towards low-level perceptual information, or a featural/surface-biased information-processing style, may compromise higher-level language processing in such individuals. Two experiments, utilizing linguistic stimuli with competing low-level/perceptual and high-level/semantic information, tested…

Perceptual Learning as a potential treatment for amblyopia: a mini-review

PubMed Central

Levi, Dennis M.; Li, Roger W.

2009-01-01

Amblyopia is a developmental abnormality that results from physiological alterations in the visual cortex and impairs form vision. It is a consequence of abnormal binocular visual experience during the “sensitive period” early in life. While amblyopia can often be reversed when treated early, conventional treatment is generally not undertaken in older children and adults. A number of studies over the last twelve years or so suggest that Perceptual Learning (PL) may provide an important new method for treating amblyopia. The aim of this mini-review is to provide a critical review and “meta-analysis” of perceptual learning in adults and children with amblyopia, with a view to extracting principles that might make PL more effective and efficient. Specifically we evaluate: What factors influence the outcome of perceptual learning?Specificity and generalization – two sides of the coin.Do the improvements last?How does PL improve visual function?Should PL be part of the treatment armamentarium? A review of the extant studies makes it clear that practicing a visual task results in a long-lasting improvement in performance in an amblyopic eye. The improvement is generally strongest for the trained eye, task, stimulus and orientation, but appears to have a broader spatial frequency bandwidth than in normal vision. Importantly, practicing on a variety of different tasks and stimuli seems to transfer to improved visual acuity. Perceptual learning operates via a reduction of internal neural noise and/or through more efficient use of the stimulus information by retuning the weighting of the information. The success of PL raises the question of whether it should become a standard part of the armamentarium for the clinical treatment of amblyopia, and suggests several important principles for effective perceptual learning in amblyopia. PMID:19250947

Prior expectations facilitate metacognition for perceptual decision.

PubMed

Sherman, M T; Seth, A K; Barrett, A B; Kanai, R

2015-09-01

The influential framework of 'predictive processing' suggests that prior probabilistic expectations influence, or even constitute, perceptual contents. This notion is evidenced by the facilitation of low-level perceptual processing by expectations. However, whether expectations can facilitate high-level components of perception remains unclear. We addressed this question by considering the influence of expectations on perceptual metacognition. To isolate the effects of expectation from those of attention we used a novel factorial design: expectation was manipulated by changing the probability that a Gabor target would be presented; attention was manipulated by instructing participants to perform or ignore a concurrent visual search task. We found that, independently of attention, metacognition improved when yes/no responses were congruent with expectations of target presence/absence. Results were modeled under a novel Bayesian signal detection theoretic framework which integrates bottom-up signal propagation with top-down influences, to provide a unified description of the mechanisms underlying perceptual decision and metacognition. Copyright © 2015 Elsevier Inc. All rights reserved.

Neurological Evidence Linguistic Processes Precede Perceptual Simulation in Conceptual Processing

PubMed Central

Louwerse, Max; Hutchinson, Sterling

2012-01-01

There is increasing evidence from response time experiments that language statistics and perceptual simulations both play a role in conceptual processing. In an EEG experiment we compared neural activity in cortical regions commonly associated with linguistic processing and visual perceptual processing to determine to what extent symbolic and embodied accounts of cognition applied. Participants were asked to determine the semantic relationship of word pairs (e.g., sky – ground) or to determine their iconic relationship (i.e., if the presentation of the pair matched their expected physical relationship). A linguistic bias was found toward the semantic judgment task and a perceptual bias was found toward the iconicity judgment task. More importantly, conceptual processing involved activation in brain regions associated with both linguistic and perceptual processes. When comparing the relative activation of linguistic cortical regions with perceptual cortical regions, the effect sizes for linguistic cortical regions were larger than those for the perceptual cortical regions early in a trial with the reverse being true later in a trial. These results map upon findings from other experimental literature and provide further evidence that processing of concept words relies both on language statistics and on perceptual simulations, whereby linguistic processes precede perceptual simulation processes. PMID:23133427

Neurological evidence linguistic processes precede perceptual simulation in conceptual processing.

PubMed

Louwerse, Max; Hutchinson, Sterling

2012-01-01

There is increasing evidence from response time experiments that language statistics and perceptual simulations both play a role in conceptual processing. In an EEG experiment we compared neural activity in cortical regions commonly associated with linguistic processing and visual perceptual processing to determine to what extent symbolic and embodied accounts of cognition applied. Participants were asked to determine the semantic relationship of word pairs (e.g., sky - ground) or to determine their iconic relationship (i.e., if the presentation of the pair matched their expected physical relationship). A linguistic bias was found toward the semantic judgment task and a perceptual bias was found toward the iconicity judgment task. More importantly, conceptual processing involved activation in brain regions associated with both linguistic and perceptual processes. When comparing the relative activation of linguistic cortical regions with perceptual cortical regions, the effect sizes for linguistic cortical regions were larger than those for the perceptual cortical regions early in a trial with the reverse being true later in a trial. These results map upon findings from other experimental literature and provide further evidence that processing of concept words relies both on language statistics and on perceptual simulations, whereby linguistic processes precede perceptual simulation processes.

Perceptual uncertainty and line-call challenges in professional tennis

PubMed Central

Mather, George

2008-01-01

Fast-moving sports such as tennis require both players and match officials to make rapid accurate perceptual decisions about dynamic events in the visual world. Disagreements arise regularly, leading to disputes about decisions such as line calls. A number of factors must contribute to these disputes, including lapses in concentration, bias and gamesmanship. Fundamental uncertainty or variability in the sensory information supporting decisions must also play a role. Modern technological innovations now provide detailed and accurate physical information that can be compared against the decisions of players and officials. The present paper uses this psychophysical data to assess the significance of perceptual limitations as a contributor to real-world decisions in professional tennis. A detailed analysis is presented of a large body of data on line-call challenges in professional tennis tournaments over the last 2 years. Results reveal that the vast majority of challenges can be explained in a direct highly predictable manner by a simple model of uncertainty in perceptual information processing. Both players and line judges are remarkably accurate at judging ball bounce position, with a positional uncertainty of less than 40 mm. Line judges are more reliable than players. Judgements are more difficult for balls bouncing near base and service lines than those bouncing near side and centre lines. There is no evidence for significant errors in localization due to image motion. PMID:18426755

Perceptual uncertainty and line-call challenges in professional tennis.

PubMed

Mather, George

2008-07-22

Fast-moving sports such as tennis require both players and match officials to make rapid accurate perceptual decisions about dynamic events in the visual world. Disagreements arise regularly, leading to disputes about decisions such as line calls. A number of factors must contribute to these disputes, including lapses in concentration, bias and gamesmanship. Fundamental uncertainty or variability in the sensory information supporting decisions must also play a role. Modern technological innovations now provide detailed and accurate physical information that can be compared against the decisions of players and officials. The present paper uses this psychophysical data to assess the significance of perceptual limitations as a contributor to real-world decisions in professional tennis. A detailed analysis is presented of a large body of data on line-call challenges in professional tennis tournaments over the last 2 years. Results reveal that the vast majority of challenges can be explained in a direct highly predictable manner by a simple model of uncertainty in perceptual information processing. Both players and line judges are remarkably accurate at judging ball bounce position, with a positional uncertainty of less than 40mm. Line judges are more reliable than players. Judgements are more difficult for balls bouncing near base and service lines than those bouncing near side and centre lines. There is no evidence for significant errors in localization due to image motion.

[Visual perceptual abilities of children with low motor abilities--a pilot study].

PubMed

Werpup-Stüwe, Lina; Petermann, Franz

2015-01-01

The results of many studies show visual perceptual deficits in children with low motor abilities. This study aims to indicate the correlation between visual-perceptual and motor abilities. The correlation of visual-perceptual and motor abilities of 41 children is measured by using the German versions of the Developmental Test of Visual Perception--Adolescent and Adult (DTVP-A) and the Movement Assessment Battery for Children--Second Edition (M-ABC-2). The visual-perceptual abilities of children with low motor abilities (n=21) are also compared to the visual-perceptual abilities of children with normal motor abilities (the control group, n=20). High correlations between the visual-perceptual and motor abilities are found. The perceptual abilities of the groups differ significantly. Nearly half of the children with low motor abilities show visual-perceptual deficits. Visual perceptual abilities of children suffering coordination disorders should always be assessed. The DTVP-A is useful, because it provides the possibilities to compare motor-reduced visual-perceptual abilities and visualmotor integration abilities and to estimate the deficit's degree.

Effects of Perceptual-Motor Programs on Children.

ERIC Educational Resources Information Center

Thomas, Jerry R.

Practical implications for physical education teachers are drawn after a review of research on perceptual motor training programs for elementary school children. Three categories of theorists are identified: those who emphasize the intellectual involvement of the child in motoric functioning; those who stress development of perceptual motor bases…

Predictive Values of Selected Auditory Perceptual Factors in Relation to Measured First Grade Reading Achievement.

ERIC Educational Resources Information Center

McNinch, George

A study was conducted to determine the relationship between auditory perceptual skills and first-grade reading success when readiness and intelligence measures were used in conjunction with auditory skills assessments. Sex differences were also considered. Six boys and six girls were randomly selected from each of 10 first-grade classrooms.…

Perceptual Stability of the Lissajous Figure Is Modulated by the Speed of Illusory Rotation.

PubMed

Weilnhammer, Veith A; Sterzer, Philipp; Hesselmann, Guido

2016-01-01

Lissajous figures represent ambiguous structure-from-motion stimuli rotating in depth and have proven to be a versatile tool to explore the cognitive and neural mechanisms underlying bistable perception. They are generated by the intersection of two sinusoids with perpendicular axes and increasing phase-shift whose frequency determines the speed of illusory 3D rotation. Recently, we found that Lissajous figures of higher shifting frequencies elicited longer perceptual phase durations and tentatively proposed a "representational momentum" account. In this study, our aim was twofold. First, we aimed to gather more behavioral evidence related to the perceptual dynamics of the Lissajous figure by simultaneously varying its shifting frequency and size. Using a conventional analysis, we investigated the effects of our experimental manipulations on transition probability (i.e., the probability that the current percept will change at the next critical stimulus configuration). Second, we sought to test the impact of our experimental factors on the occurrence of transitions in bistable perception by means of a Bayesian approach that can be used to directly quantify the impact of contextual cues on perceptual stability. We thereby estimated the implicit prediction of perceptual stability and how it is modulated by experimental manipulations.

Selective attention in perceptual adjustments to voice.

PubMed

Mullennix, J W; Howe, J N

1999-10-01

The effects of perceptual adjustments to voice information on the perception of isolated spoken words were examined. In two experiments, spoken target words were preceded or followed within a trial by a neutral word spoken in the same voice or in a different voice as the target. Over-all, words were reproduced more accurately on trials on which the voice of the neutral word matched the voice of the spoken target word, suggesting that perceptual adjustments to voice interfere with word processing. This result, however, was mediated by selective attention to voice. The results provide further evidence of a close processing relationship between perceptual adjustments to voice and spoken word recognition.

Effects of Perceptually Rich Manipulatives on Preschoolers' Counting Performance: Established Knowledge Counts

ERIC Educational Resources Information Center

Petersen, Lori A.; McNeil, Nicole M.

2013-01-01

Educators often use concrete objects to help children understand mathematics concepts. However, findings on the effectiveness of concrete objects are mixed. The present study examined how two factors--perceptual richness and established knowledge of the objects--combine to influence children's counting performance. In two experiments, preschoolers…

A Guide for Perceptual-Motor Training Activities.

ERIC Educational Resources Information Center

South Euclid - Lyndhurst City Schools, Lyndhurst, OH.

This document has been prepared as part of a kindergarten perceptual-training program of the South Euclid-Lyndhurst City School District near Cleveland, Ohio. The guide contains information on training and procedures related to perceptual-motor learning. This information is structured primarily into 150 lesson plans, devised as 30-minute sessions…

Field Dependence, Perceptual Instability, and Sex Differences.

ERIC Educational Resources Information Center

Bergum, Judith E.; Bergum, Bruce O.

Recent studies have shown perceptual instability to be related to visual creativity as reflected in career choice. In general, those who display greater perceptual instability perceive themselves to be more creative and tend to choose careers related to visual creativity, regardless of their gender. To test the hypothesis that field independents…

Generalization of perceptual and motor learning: a causal link with memory encoding and consolidation?

PubMed

Censor, N

2013-10-10

In both perceptual and motor learning, numerous studies have shown specificity of learning to the trained eye or hand and to the physical features of the task. However, generalization of learning is possible in both perceptual and motor domains. Here, I review evidence for perceptual and motor learning generalization, suggesting that generalization patterns are affected by the way in which the original memory is encoded and consolidated. Generalization may be facilitated during fast learning, with possible engagement of higher-order brain areas recurrently interacting with the primary visual or motor cortices encoding the stimuli or movements' memories. Such generalization may be supported by sleep, involving functional interactions between low and higher-order brain areas. Repeated exposure to the task may alter generalization patterns of learning and overall offline learning. Development of unifying frameworks across learning modalities and better understanding of the conditions under which learning can generalize may enable to gain insight regarding the neural mechanisms underlying procedural learning and have useful clinical implications. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

The Effects of Differential Training Procedures on Linked Perceptual Class Formation

ERIC Educational Resources Information Center

Fields, Lanny; Tittelbach, Danielle; Shamoun, Kimberly; Watanabe, Mari; Fitzer, Adrienne; Matneja, Priya

2007-01-01

When the stimuli in one perceptual class (A') become related to the stimuli in another perceptual class (B'), the two are functioning as a single "linked perceptual class". A common linked perceptual class would be the sounds of a person's voice (class A') and the pictures of that person (class B'). Such classes are ubiquitous in real…

The impact of dissociation on perceptual priming and intrusions after listening to auditory narratives.

PubMed

Dorahy, Martin J; Peck, Rowan K; Huntjens, Rafaele J C

2016-01-01

This study investigates the causal role of dissociation in intrusive memory development and possible underlying aberrant memory processes (e.g., increased perceptual priming). Using an audio-only adaption of the trauma film paradigm, we divided 60 participants into 3 conditions and presented them with different visual tasks-mirror staring, dot staring, or neutral images. The former 2 conditions were hypothesized to induce dissociation. Postaudio, a number of factors were assessed, including state dissociation, perceptual priming and conceptual priming, as well as intrusions over 3 days. Participants in the dissociation conditions displayed an increase in perceptual priming compared to those in the control condition and reported more distressing intrusions. No differences were found in conceptual priming and the overall number of intrusions between conditions. Findings contribute to the growing knowledge on the impact of dissociation and cognitive processing in the etiology of posttraumatic stress disorder intrusions.

Adaptive sampling of information in perceptual decision-making.

PubMed

Cassey, Thomas C; Evens, David R; Bogacz, Rafal; Marshall, James A R; Ludwig, Casimir J H

2013-01-01

In many perceptual and cognitive decision-making problems, humans sample multiple noisy information sources serially, and integrate the sampled information to make an overall decision. We derive the optimal decision procedure for two-alternative choice tasks in which the different options are sampled one at a time, sources vary in the quality of the information they provide, and the available time is fixed. To maximize accuracy, the optimal observer allocates time to sampling different information sources in proportion to their noise levels. We tested human observers in a corresponding perceptual decision-making task. Observers compared the direction of two random dot motion patterns that were triggered only when fixated. Observers allocated more time to the noisier pattern, in a manner that correlated with their sensory uncertainty about the direction of the patterns. There were several differences between the optimal observer predictions and human behaviour. These differences point to a number of other factors, beyond the quality of the currently available sources of information, that influences the sampling strategy.

Common mechanisms of human perceptual and motor learning

PubMed Central

Censor, Nitzan; Sagi, Dov; Cohen, Leonardo G.

2016-01-01

The adult mammalian brain has a remarkable capacity to learn in both the perceptual and motor domains through the formation and consolidation of memories. Such practice-enabled procedural learning results in perceptual and motor skill improvements. Here, we examine evidence supporting the notion that perceptual and motor learning in humans exhibit analogous properties, including similarities in temporal dynamics and the interactions between primary cortical and higher-order brain areas. These similarities may point to the existence of a common general mechanism for learning in humans. PMID:22903222

The assessment of aesthetic and perceptual aspects within environmental impact assessment of renewable energy projects in Italy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tolli, Michela, E-mail: michela.tolli@uniroma1.it; Recanatesi, Fabio, E-mail: fabio.rec@unitus.it; Piccinno, Matteo

The main aim of this paper is to explore how perceptual and aesthetic impact analyses are considered in Environmental Impact Assessment (EIA), with specific reference to Italian renewable energy projects. To investigate this topic, the paper starts by establishing which factors are linked with perceptual and aesthetic impacts and why it is important to analyze these aspects, which are also related to legislative provisions and procedures in Europe and in Italy. In particular the paper refers to renewable energy projects because environmental policies are encouraging more and more investment in this kind of primary resource. The growing interest in thismore » type of energy is leading to the realization of projects which change the governance of territories, with inevitable effects on the landscape from the aesthetic and perceptual points of view. Legislative references to EIA, including the latest directive regarding this topic show the importance of integrating the assessment of environmental and perceptual impacts, thus there is a need to improve EIA methodological approaches to this purpose. This paper proposes a profile of aesthetic and perceptual impact analysis in EIA for renewable energy projects in Italy, and concludes with recommendations as to how this kind of analysis could be improved. - Highlights: • We analyze 29 EIA Reports of Italian renewable energy projects. • We examine esthetic and perceptual aspects present in Italian EIA reports. • We identified inconsistency in use of methods for esthetic and perceptual aspects. • Local populations are rarely included as stakeholders in EIAs. • A shared understanding of perceptual and esthetic issues in EIA proceedings is required.« less

Perceptual and categorical decision making: goal-relevant representation of two domains at different levels of abstraction.

PubMed

Shankar, Swetha; Kayser, Andrew S

2017-06-01

To date it has been unclear whether perceptual decision making and rule-based categorization reflect activation of similar cognitive processes and brain regions. On one hand, both map potentially ambiguous stimuli to a smaller set of motor responses. On the other hand, decisions about perceptual salience typically concern concrete sensory representations derived from a noisy stimulus, while categorization is typically conceptualized as an abstract decision about membership in a potentially arbitrary set. Previous work has primarily examined these types of decisions in isolation. Here we independently varied salience in both the perceptual and categorical domains in a random dot-motion framework by manipulating dot-motion coherence and motion direction relative to a category boundary, respectively. Behavioral and modeling results suggest that categorical (more abstract) information, which is more relevant to subjects' decisions, is weighted more strongly than perceptual (more concrete) information, although they also have significant interactive effects on choice. Within the brain, BOLD activity within frontal regions strongly differentiated categorical salience and weakly differentiated perceptual salience; however, the interaction between these two factors activated similar frontoparietal brain networks. Notably, explicitly evaluating feature interactions revealed a frontal-parietal dissociation: parietal activity varied strongly with both features, but frontal activity varied with the combined strength of the information that defined the motor response. Together, these data demonstrate that frontal regions are driven by decision-relevant features and argue that perceptual decisions and rule-based categorization reflect similar cognitive processes and activate similar brain networks to the extent that they define decision-relevant stimulus-response mappings. NEW & NOTEWORTHY Here we study the behavioral and neural dynamics of perceptual categorization when

Perceptual and categorical decision making: goal-relevant representation of two domains at different levels of abstraction

PubMed Central

Kayser, Andrew S.

2017-01-01

To date it has been unclear whether perceptual decision making and rule-based categorization reflect activation of similar cognitive processes and brain regions. On one hand, both map potentially ambiguous stimuli to a smaller set of motor responses. On the other hand, decisions about perceptual salience typically concern concrete sensory representations derived from a noisy stimulus, while categorization is typically conceptualized as an abstract decision about membership in a potentially arbitrary set. Previous work has primarily examined these types of decisions in isolation. Here we independently varied salience in both the perceptual and categorical domains in a random dot-motion framework by manipulating dot-motion coherence and motion direction relative to a category boundary, respectively. Behavioral and modeling results suggest that categorical (more abstract) information, which is more relevant to subjects’ decisions, is weighted more strongly than perceptual (more concrete) information, although they also have significant interactive effects on choice. Within the brain, BOLD activity within frontal regions strongly differentiated categorical salience and weakly differentiated perceptual salience; however, the interaction between these two factors activated similar frontoparietal brain networks. Notably, explicitly evaluating feature interactions revealed a frontal-parietal dissociation: parietal activity varied strongly with both features, but frontal activity varied with the combined strength of the information that defined the motor response. Together, these data demonstrate that frontal regions are driven by decision-relevant features and argue that perceptual decisions and rule-based categorization reflect similar cognitive processes and activate similar brain networks to the extent that they define decision-relevant stimulus-response mappings. NEW & NOTEWORTHY Here we study the behavioral and neural dynamics of perceptual categorization when

Beta oscillations define discrete perceptual cycles in the somatosensory domain.

PubMed

Baumgarten, Thomas J; Schnitzler, Alfons; Lange, Joachim

2015-09-29

Whether seeing a movie, listening to a song, or feeling a breeze on the skin, we coherently experience these stimuli as continuous, seamless percepts. However, there are rare perceptual phenomena that argue against continuous perception but, instead, suggest discrete processing of sensory input. Empirical evidence supporting such a discrete mechanism, however, remains scarce and comes entirely from the visual domain. Here, we demonstrate compelling evidence for discrete perceptual sampling in the somatosensory domain. Using magnetoencephalography (MEG) and a tactile temporal discrimination task in humans, we find that oscillatory alpha- and low beta-band (8-20 Hz) cycles in primary somatosensory cortex represent neurophysiological correlates of discrete perceptual cycles. Our results agree with several theoretical concepts of discrete perceptual sampling and empirical evidence of perceptual cycles in the visual domain. Critically, these results show that discrete perceptual cycles are not domain-specific, and thus restricted to the visual domain, but extend to the somatosensory domain.

Transfer of perceptual learning between different visual tasks

PubMed Central

McGovern, David P.; Webb, Ben S.; Peirce, Jonathan W.

2012-01-01

Practice in most sensory tasks substantially improves perceptual performance. A hallmark of this ‘perceptual learning' is its specificity for the basic attributes of the trained stimulus and task. Recent studies have challenged the specificity of learned improvements, although transfer between substantially different tasks has yet to be demonstrated. Here, we measure the degree of transfer between three distinct perceptual tasks. Participants trained on an orientation discrimination, a curvature discrimination, or a ‘global form' task, all using stimuli comprised of multiple oriented elements. Before and after training they were tested on all three and a contrast discrimination control task. A clear transfer of learning was observed, in a pattern predicted by the relative complexity of the stimuli in the training and test tasks. Our results suggest that sensory improvements derived from perceptual learning can transfer between very different visual tasks. PMID:23048211

Transfer of perceptual learning between different visual tasks.

PubMed

McGovern, David P; Webb, Ben S; Peirce, Jonathan W

2012-10-09

Practice in most sensory tasks substantially improves perceptual performance. A hallmark of this 'perceptual learning' is its specificity for the basic attributes of the trained stimulus and task. Recent studies have challenged the specificity of learned improvements, although transfer between substantially different tasks has yet to be demonstrated. Here, we measure the degree of transfer between three distinct perceptual tasks. Participants trained on an orientation discrimination, a curvature discrimination, or a 'global form' task, all using stimuli comprised of multiple oriented elements. Before and after training they were tested on all three and a contrast discrimination control task. A clear transfer of learning was observed, in a pattern predicted by the relative complexity of the stimuli in the training and test tasks. Our results suggest that sensory improvements derived from perceptual learning can transfer between very different visual tasks.

Perceptual Bias and Loudness Change: An Investigation of Memory, Masking, and Psychophysiology

NASA Astrophysics Data System (ADS)

Olsen, Kirk N.

Loudness is a fundamental aspect of human auditory perception that is closely associated with a sound's physical acoustic intensity. The dynamic quality of intensity change is an inherent acoustic feature in real-world listening domains such as speech and music. However, perception of loudness change in response to continuous intensity increases (up-ramps) and decreases (down-ramps) has received relatively little empirical investigation. Overestimation of loudness change in response to up-ramps is said to be linked to an adaptive survival response associated with looming (or approaching) motion in the environment. The hypothesised 'perceptual bias' to looming auditory motion suggests why perceptual overestimation of up-ramps may occur; however it does not offer a causal explanation. It is concluded that post-stimulus judgements of perceived loudness change are significantly affected by a cognitive recency response bias that, until now, has been an artefact of experimental procedure. Perceptual end-level differences caused by duration specific sensory adaptation at peripheral and/or central stages of auditory processing may explain differences in post-stimulus judgements of loudness change. Experiments that investigate human responses to acoustic intensity dynamics, encompassing topics from basic auditory psychophysics (e.g., sensory adaptation) to cognitive-emotional appraisal of increasingly complex stimulus events such as music and auditory warnings, are proposed for future research.

What makes viewpoint-invariant properties perceptually salient?

PubMed

Jacobs, David W

2003-07-01

It has been noted that many of the perceptually salient image properties identified by the Gestalt psychologists, such as collinearity, parallelism, and good continuation, age invariant to changes in viewpoint. However, I show that viewpoint invariance is not sufficient to distinguish these Gestalt properties; one can define an infinite number of viewpoint-invariant properties that are not perceptually salient. I then show that generally, the perceptually salient viewpoint-invariant properties are minimal, in the sense that they can be derived by using less image information than for nonsalient properties. This finding provides support for the hypothesis that the biological relevance of an image property is determined both by the extent to which it provides information about the world and by the ease with which this property can be computed. [An abbreviated version of this work, including technical details that are avoided in this paper, is contained in K. Boyer and S. Sarker, eds., Perceptual Organization for Artificial Vision Systems (Kluwer Academic, Dordrecht, The Netherlands, 2000), pp. 121-138.

Perceptual transparency from image deformation.

PubMed

Kawabe, Takahiro; Maruya, Kazushi; Nishida, Shin'ya

2015-08-18

Human vision has a remarkable ability to perceive two layers at the same retinal locations, a transparent layer in front of a background surface. Critical image cues to perceptual transparency, studied extensively in the past, are changes in luminance or color that could be caused by light absorptions and reflections by the front layer, but such image changes may not be clearly visible when the front layer consists of a pure transparent material such as water. Our daily experiences with transparent materials of this kind suggest that an alternative potential cue of visual transparency is image deformations of a background pattern caused by light refraction. Although previous studies have indicated that these image deformations, at least static ones, play little role in perceptual transparency, here we show that dynamic image deformations of the background pattern, which could be produced by light refraction on a moving liquid's surface, can produce a vivid impression of a transparent liquid layer without the aid of any other visual cues as to the presence of a transparent layer. Furthermore, a transparent liquid layer perceptually emerges even from a randomly generated dynamic image deformation as long as it is similar to real liquid deformations in its spatiotemporal frequency profile. Our findings indicate that the brain can perceptually infer the presence of "invisible" transparent liquids by analyzing the spatiotemporal structure of dynamic image deformation, for which it uses a relatively simple computation that does not require high-level knowledge about the detailed physics of liquid deformation.

Moving the Weber Fraction: The Perceptual Precision for Moment of Inertia Increases with Exploration Force

PubMed Central

Debats, Nienke B.; Kingma, Idsart; Beek, Peter J.; Smeets, Jeroen B. J.

2012-01-01

How does the magnitude of the exploration force influence the precision of haptic perceptual estimates? To address this question, we examined the perceptual precision for moment of inertia (i.e., an object's “angular mass”) under different force conditions, using the Weber fraction to quantify perceptual precision. Participants rotated a rod around a fixed axis and judged its moment of inertia in a two-alternative forced-choice task. We instructed different levels of exploration force, thereby manipulating the magnitude of both the exploration force and the angular acceleration. These are the two signals that are needed by the nervous system to estimate moment of inertia. Importantly, one can assume that the absolute noise on both signals increases with an increase in the signals' magnitudes, while the relative noise (i.e., noise/signal) decreases with an increase in signal magnitude. We examined how the perceptual precision for moment of inertia was affected by this neural noise. In a first experiment we found that a low exploration force caused a higher Weber fraction (22%) than a high exploration force (13%), which suggested that the perceptual precision was constrained by the relative noise. This hypothesis was supported by the result of a second experiment, in which we found that the relationship between exploration force and Weber fraction had a similar shape as the theoretical relationship between signal magnitude and relative noise. The present study thus demonstrated that the amount of force used to explore an object can profoundly influence the precision by which its properties are perceived. PMID:23028437

Language within your reach: near-far perceptual space and spatial demonstratives.

PubMed

Coventry, Kenny R; Valdés, Berenice; Castillo, Alejandro; Guijarro-Fuentes, Pedro

2008-09-01

Spatial demonstratives (this/that) play a crucial role when indicating object locations using language. However, the relationship between the use of these proximal and distal linguistic descriptors and the near (peri-personal) versus far (extra-personal) perceptual space distinction is a source of controversy [Kemmerer, D. (1999). "Near" and "far" in language and perception. Cognition 73, 35-63], and has been hitherto under investigated. Two experiments examined the influence of object distance from speaker, tool use (participants pointed at objects with their finger/arm or with a stick), and interaction with objects (whether or not participants placed objects themselves) on spatial demonstrative use (e.g. this/that red triangle) in English (this/that) and Spanish (este/ese/aquel). The results show that the use of demonstratives across two languages is affected by distance from speaker and by both tool use and interaction with objects. These results support the view that spatial demonstrative use corresponds with a basic distinction between near and far perceptual space.

Perceptual Grouping, Not Emotion, Accounts for Search Asymmetries with Schematic Faces

ERIC Educational Resources Information Center

Becker, Stefanie I.; Horstmann, Gernot; Remington, Roger W.

2011-01-01

Several different explanations have been proposed to account for the search asymmetry (SA) for angry schematic faces (i.e., the fact that an angry face target among friendly faces can be found faster than vice versa). The present study critically tested the perceptual grouping account, (a) that the SA is not due to emotional factors, but to…

Phenomenology and neurobiology of self disorder in schizophrenia: Primary factors.

PubMed

Borda, Juan P; Sass, Louis A

2015-12-01

Schizophrenia is a heterogeneous syndrome, varying between persons and over course of illness. In this and a companion article, we argue that comprehension of this condition or set of conditions may require combining a phenomenological perspective emphasizing disorders of basic-self experience ("ipseity disturbance") with a multidimensional appreciation of possible neurobiological correlates--both primary and secondary. Previous attempts to link phenomenology and neurobiology generally focus on a single neurocognitive factor. We consider diverse aspects of schizophrenia in light of a diverse, albeit interacting, set of neurocognitive abnormalities, examining both synchronic (structural) interdependence and diachronic (temporal) succession. In this article we focus on the primary or foundational role of early perceptual and motoric disturbances that affect perceptual organization and especially intermodal or multisensory perceptual integration (“perceptual dys-integration”). These disturbances are discussed in terms of their implications for three interconnected aspects of selfhood in schizophrenia, primary forms of: disrupted "hold" or "grip" on the world, hyperreflexivity, diminished self-presence (self-affection). Disturbances of organization or integration imply forms of perceptual incoherence or diminished cognitive coordination. The effect is to disrupt one's ability to apprehend the world in holistic, vital, or contextually grounded fashion, or to fully identify with or experience the unity of one's own body or thinking--thereby generating an early and profound (albeit often subtle) disruption or diminishment of basic or core self and of the sense of existing in a coherent world. We discuss interrelationships or possible complementarities between these three aspects, and consider their relevance for a neurodevelopmental account of schizophrenia. Copyright © 2015 Elsevier B.V. All rights reserved.

Motivation and intelligence drive auditory perceptual learning.

PubMed

Amitay, Sygal; Halliday, Lorna; Taylor, Jenny; Sohoglu, Ediz; Moore, David R

2010-03-23

Although feedback on performance is generally thought to promote perceptual learning, the role and necessity of feedback remain unclear. We investigated the effect of providing varying amounts of positive feedback while listeners attempted to discriminate between three identical tones on learning frequency discrimination. Using this novel procedure, the feedback was meaningless and random in relation to the listeners' responses, but the amount of feedback provided (or lack thereof) affected learning. We found that a group of listeners who received positive feedback on 10% of the trials improved their performance on the task (learned), while other groups provided either with excess (90%) or with no feedback did not learn. Superimposed on these group data, however, individual listeners showed other systematic changes of performance. In particular, those with lower non-verbal IQ who trained in the no feedback condition performed more poorly after training. This pattern of results cannot be accounted for by learning models that ascribe an external teacher role to feedback. We suggest, instead, that feedback is used to monitor performance on the task in relation to its perceived difficulty, and that listeners who learn without the benefit of feedback are adept at self-monitoring of performance, a trait that also supports better performance on non-verbal IQ tests. These results show that 'perceptual' learning is strongly influenced by top-down processes of motivation and intelligence.

Affect, affective disorder and schizophrenia. A neuropsychological investigation of right hemisphere function.

PubMed

David, A S; Cutting, J C

1990-04-01

Performance on a happy-sad chimeric face test was used to examine the role of right hemisphere activation in positive and negative affect, both normal and abnormal, as well as in schizophrenia. This test is known to elicit a left-sided perceptual bias in right-handed normal subjects. Happy and sad mood in normals did not influence the perceptual bias. Depression and mania were associated with reduced and increased biases respectively, while schizophrenics showed no bias to either side. Possible explanations are right hemisphere hyperfunction in mania, moderate relative hypofunction in depression, and severe relative hypofunction in schizophrenia. The marked difference between mania and schizophrenia supports distinct pathophysiologies underlying the two conditions.

Transfer of perceptual-motor training and the space adaptation syndrome

NASA Technical Reports Server (NTRS)

Kennedy, R. S.; Berbaum, K. S.; Williams, M. C.; Brannan, J.; Welch, R. B.

1987-01-01

Perceptual cue conflict may be the basis for the symptoms which are experienced by space travelers in microgravity conditions. Recovery has been suggested to take place after perceptual modification or reinterpretation. To elucidate this process, 10 subjects who repeatedly experienced a visual/vestibular conflict over trials and days, were tested in a similar but not identical perceptual situation (pseudo-Coriolis) to determine whether any savings in perceptual adaptation had occurred as compared to an unpracticed control group (N = 40). The practiced subjects experienced lessening dizziness and ataxia within and over sessions.

Age Learning Factors Affecting Pilot Education.

ERIC Educational Resources Information Center

Torbert, Brison

This document, intended for pilot education and flight safety specialists, consists chiefly of a review of the literature on physiological factors that affect pilot education and an examination of environmental factors that should be scrutinized in order to improve the effectiveness of aviation learning facilities. The physiological factors…

Perceptual, Cognitive, and Personality Rigidity in Parkinson’s Disease

PubMed Central

Díaz-Santos, Mirella; Cao, Bo; Yazdanbakhsh, Arash; Norton, Daniel J.; Neargarder, Sandy; Cronin-Golomb, Alice

2015-01-01

Parkinson’s disease (PD) is associated with motor and non-motor rigidity symptoms (e.g., cognitive and personality). The question is raised as to whether rigidity in PD also extends to perception, and if so, whether perceptual, cognitive, and personality rigidities are correlated. Bistable stimuli were presented to 28 non-demented individuals with PD and 26 normal control adults (NC). Necker cube perception and binocular rivalry were examined during passive viewing, and the Necker cube was additionally used for two volitional-control conditions: Hold one percept in front, and Switch between the two percepts. Relative to passive viewing, PD were significantly less able than NC to reduce dominance durations in the Switch condition, indicating perceptual rigidity. Tests of cognitive flexibility and a personality questionnaire were administered to explore the association with perceptual rigidity. Cognitive flexibility was not correlated with perceptual rigidity for either group. Personality (novelty seeking) correlated with dominance durations on Necker passive viewing for PD but not NC. The results indicate the presence in mild-moderate PD of perceptual rigidity and suggest shared neural substrates with novelty seeking, but functional divergence from those supporting cognitive flexibility. The possibility is raised that perceptual rigidity may be a harbinger of cognitive inflexibility later in the disease course. PMID:25640973

Perceptual attraction in tool use: evidence for a reliability-based weighting mechanism.

PubMed

Debats, Nienke B; Ernst, Marc O; Heuer, Herbert

2017-04-01

Humans are well able to operate tools whereby their hand movement is linked, via a kinematic transformation, to a spatially distant object moving in a separate plane of motion. An everyday example is controlling a cursor on a computer monitor. Despite these separate reference frames, the perceived positions of the hand and the object were found to be biased toward each other. We propose that this perceptual attraction is based on the principles by which the brain integrates redundant sensory information of single objects or events, known as optimal multisensory integration. That is, 1 ) sensory information about the hand and the tool are weighted according to their relative reliability (i.e., inverse variances), and 2 ) the unisensory reliabilities sum up in the integrated estimate. We assessed whether perceptual attraction is consistent with optimal multisensory integration model predictions. We used a cursor-control tool-use task in which we manipulated the relative reliability of the unisensory hand and cursor position estimates. The perceptual biases shifted according to these relative reliabilities, with an additional bias due to contextual factors that were present in experiment 1 but not in experiment 2 The biased position judgments' variances were, however, systematically larger than the predicted optimal variances. Our findings suggest that the perceptual attraction in tool use results from a reliability-based weighting mechanism similar to optimal multisensory integration, but that certain boundary conditions for optimality might not be satisfied. NEW & NOTEWORTHY Kinematic tool use is associated with a perceptual attraction between the spatially separated hand and the effective part of the tool. We provide a formal account for this phenomenon, thereby showing that the process behind it is similar to optimal integration of sensory information relating to single objects. Copyright © 2017 the American Physiological Society.

Perceptual Decision Making in Rodents, Monkeys, and Humans.

PubMed

Hanks, Timothy D; Summerfield, Christopher

2017-01-04

Perceptual decision making is the process by which animals detect, discriminate, and categorize information from the senses. Over the past two decades, understanding how perceptual decisions are made has become a central theme in the neurosciences. Exceptional progress has been made by recording from single neurons in the cortex of the macaque monkey and using computational models from mathematical psychology to relate these neural data to behavior. More recently, however, the range of available techniques and paradigms has dramatically broadened, and researchers have begun to harness new approaches to explore how rodents and humans make perceptual decisions. The results have illustrated some striking convergences with findings from the monkey, but also raised new questions and provided new theoretical insights. In this review, we summarize key findings, and highlight open challenges, for understanding perceptual decision making in rodents, monkeys, and humans. Copyright © 2017 Elsevier Inc. All rights reserved.

Perceptual rate normalization in naturally produced bilabial stops

NASA Astrophysics Data System (ADS)

Nagao, Kyoko; de Jong, Kenneth

2003-10-01

The perception of voicing categories is affected by the speaking rate, so that listeners' category boundaries on a VOT continuum shift to a lower value when the syllable duration decreases (Miller and Volaitis, 1989; Volaitis and Miller, 1992). Previous rate normalization effects have been found using computer-generated stimuli. This study examines the effect of speech rate on voicing categorization in naturally produced speech. Four native speakers of American English repeated syllables (/bi/ and /pi/) at increasing rates in time with a metronome. Three-syllable stimuli were spliced from the repetitive speech. These stimuli contained natural decreases in VOT with faster speech rates. Besides, this rate effect on VOT was larger for /p/ than /b/, so that VOT values for /b/ and /p/ overlapped at the fastest rates. Eighteen native listeners of American English were presented with 168 stimuli and asked to identify the consonant. Perceptual category boundaries occur at VOT values 15 ms shorter than the values reported for synthesized stimuli. This difference may be due to the extraordinarily wide range of VOT values in previous studies. The values found in the current study closely match the actual division point for /b/ and /p/. The underlying mechanism of perceptual normalization will be discussed.

Perceptual crossing: the simplest online paradigm

PubMed Central

Auvray, Malika; Rohde, Marieke

2012-01-01

Researchers in social cognition increasingly realize that many phenomena cannot be understood by investigating offline situations only, focusing on individual mechanisms and an observer perspective. There are processes of dynamic emergence specific to online situations, when two or more persons are engaged in a real-time interaction that are more than just the sum of the individual capacities or behaviors, and these require the study of online social interaction. Auvray et al.'s (2009) perceptual crossing paradigm offers possibly the simplest paradigm for studying such online interactions: two persons, a one-dimensional space, one bit of information, and a yes/no answer. This study has provoked a lot of resonance in different areas of research, including experimental psychology, computer/robot modeling, philosophy, psychopathology, and even in the field of design. In this article, we review and critically assess this body of literature. We give an overview of both behavioral experimental research and simulated agent modeling done using the perceptual crossing paradigm. We discuss different contexts in which work on perceptual crossing has been cited. This includes the controversy about the possible constitutive role of perceptual crossing for social cognition. We conclude with an outlook on future research possibilities, in particular those that could elucidate the link between online interaction dynamics and individual social cognition. PMID:22723776

Perceptual Stability of the Lissajous Figure Is Modulated by the Speed of Illusory Rotation

PubMed Central

Weilnhammer, Veith A.; Sterzer, Philipp; Hesselmann, Guido

2016-01-01

Lissajous figures represent ambiguous structure-from-motion stimuli rotating in depth and have proven to be a versatile tool to explore the cognitive and neural mechanisms underlying bistable perception. They are generated by the intersection of two sinusoids with perpendicular axes and increasing phase-shift whose frequency determines the speed of illusory 3D rotation. Recently, we found that Lissajous figures of higher shifting frequencies elicited longer perceptual phase durations and tentatively proposed a “representational momentum” account. In this study, our aim was twofold. First, we aimed to gather more behavioral evidence related to the perceptual dynamics of the Lissajous figure by simultaneously varying its shifting frequency and size. Using a conventional analysis, we investigated the effects of our experimental manipulations on transition probability (i.e., the probability that the current percept will change at the next critical stimulus configuration). Second, we sought to test the impact of our experimental factors on the occurrence of transitions in bistable perception by means of a Bayesian approach that can be used to directly quantify the impact of contextual cues on perceptual stability. We thereby estimated the implicit prediction of perceptual stability and how it is modulated by experimental manipulations. PMID:27560958

Detecting perceptual groupings in textures by continuity considerations

NASA Technical Reports Server (NTRS)

Greene, Richard J.

1990-01-01

A generalization is presented for the second derivative of a Gaussian D(sup 2)G operator to apply to problems of perceptual organization involving textures. Extensions to other problems of perceptual organization are evident and a new research direction can be established. The technique presented is theoretically pleasing since it has the potential of unifying the entire area of image segmentation under the mathematical notion of continuity and presents a single algorithm to form perceptual groupings where many algorithms existed previously. The eventual impact on both the approach and technique of image processing segmentation operations could be significant.

Fast perceptual image hash based on cascade algorithm

NASA Astrophysics Data System (ADS)

Ruchay, Alexey; Kober, Vitaly; Yavtushenko, Evgeniya

2017-09-01

In this paper, we propose a perceptual image hash algorithm based on cascade algorithm, which can be applied in image authentication, retrieval, and indexing. Image perceptual hash uses for image retrieval in sense of human perception against distortions caused by compression, noise, common signal processing and geometrical modifications. The main disadvantage of perceptual hash is high time expenses. In the proposed cascade algorithm of image retrieval initializes with short hashes, and then a full hash is applied to the processed results. Computer simulation results show that the proposed hash algorithm yields a good performance in terms of robustness, discriminability, and time expenses.

Perceptual telerobotics

NASA Technical Reports Server (NTRS)

Ligomenides, Panos A.

1989-01-01

A sensory world modeling system, congruent with a human expert's perception, is proposed. The Experiential Knowledge Base (EKB) system can provide a highly intelligible communication interface for telemonitoring and telecontrol of a real time robotic system operating in space. Paradigmatic acquisition of empirical perceptual knowledge, and real time experiential pattern recognition and knowledge integration are reviewed. The cellular architecture and operation of the EKB system are also examined.

Environmental Factors Affecting Preschoolers' Motor Development

ERIC Educational Resources Information Center

Venetsanou, Fotini; Kambas, Antonis

2010-01-01

The process of development occurs according to the pattern established by the genetic potential and also by the influence of environmental factors. The aim of the present study was to focus on the main environmental factors affecting motor development. The review of the literature revealed that family features, such as socioeconomic status,…

Enhancing Academic Performance: Seven Perceptual Styles of Learning.

ERIC Educational Resources Information Center

Higbee, Jeanne L.; And Others

1991-01-01

Presents Galbraith and James's taxonomy of seven perceptual modalities (i.e., print, aural, interactive, visual, haptic, kinesthetic, and olfactory). Discusses ways educators can demonstrate perceptual modalities in the classroom and help students identify their personal style of learning. Explains how this knowledge can facilitate learning in a…

Motivation alters response bias and neural activation patterns in a perceptual decision-making task.

PubMed

Reckless, G E; Bolstad, I; Nakstad, P H; Andreassen, O A; Jensen, J

2013-05-15

Motivation has been demonstrated to affect individuals' response strategies in economic decision-making, however, little is known about how motivation influences perceptual decision-making behavior or its related neural activity. Given the important role motivation plays in shaping our behavior, a better understanding of this relationship is needed. A block-design, continuous performance, perceptual decision-making task where participants were asked to detect a picture of an animal among distractors was used during functional magnetic resonance imaging (fMRI). The effect of positive and negative motivation on sustained activity within regions of the brain thought to underlie decision-making was examined by altering the monetary contingency associated with the task. In addition, signal detection theory was used to investigate the effect of motivation on detection sensitivity, response bias and response time. While both positive and negative motivation resulted in increased sustained activation in the ventral striatum, fusiform gyrus, left dorsolateral prefrontal cortex (DLPFC) and ventromedial prefrontal cortex, only negative motivation resulted in the adoption of a more liberal, closer to optimal response bias. This shift toward a liberal response bias correlated with increased activation in the left DLPFC, but did not result in improved task performance. The present findings suggest that motivation alters aspects of the way perceptual decisions are made. Further, this altered response behavior is reflected in a change in left DLPFC activation, a region involved in the computation of perceptual decisions. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Self-stimulatory behavior and perceptual reinforcement.

PubMed Central

Lovaas, I; Newsom, C; Hickman, C

1987-01-01

Self-stimulatory behavior is repetitive, stereotyped, functionally autonomous behavior seen in both normal and developmentally disabled populations, yet no satisfactory theory of its development and major characteristics has previously been offered. We present here a detailed hypothesis of the acquisition and maintenance of self-stimulatory behavior, proposing that the behaviors are operant responses whose reinforcers are automatically produced interoceptive and exteroceptive perceptual consequences. The concept of perceptual stimuli and reinforcers, the durability of self-stimulatory behaviors, the sensory extinction effect, the inverse relationship between self-stimulatory and other behaviors, the blocking effect of self-stimulatory behavior on new learning, and response substitution effects are discussed in terms of the hypothesis. Support for the hypothesis from the areas of sensory reinforcement and sensory deprivation is also reviewed. Limitations of major alternative theories are discussed, along with implications of the perceptual reinforcement hypothesis for the treatment of excessive self-stimulatory behavior and for theoretical conceptualizations of functionally related normal and pathological behaviors. PMID:3583964

Memory: enduring traces of perceptual and reflective attention.

PubMed

Chun, Marvin M; Johnson, Marcia K

2011-11-17

Attention and memory are typically studied as separate topics, but they are highly intertwined. Here we discuss the relation between memory and two fundamental types of attention: perceptual and reflective. Memory is the persisting consequence of cognitive activities initiated by and/or focused on external information from the environment (perceptual attention) and initiated by and/or focused on internal mental representations (reflective attention). We consider three key questions for advancing a cognitive neuroscience of attention and memory: to what extent do perception and reflection share representational areas? To what extent are the control processes that select, maintain, and manipulate perceptual and reflective information subserved by common areas and networks? During perception and reflection, to what extent are common areas responsible for binding features together to create complex, episodic memories and for reviving them later? Considering similarities and differences in perceptual and reflective attention helps integrate a broad range of findings and raises important unresolved issues. Copyright © 2011 Elsevier Inc. All rights reserved.

Memory: Enduring Traces of Perceptual and Reflective Attention

PubMed Central

Chun, Marvin M.; Johnson, Marcia K.

2011-01-01

Attention and memory are typically studied as separate topics, but they are highly intertwined. Here we discuss the relation between memory and two fundamental types of attention: perceptual and reflective. Memory is the persisting consequence of cognitive activities initiated by and/or focused on external information from the environment (perceptual attention) and initiated by and/or focused on internal mental representations (reflective attention). We consider three key questions for advancing a cognitive neuroscience of attention and memory: To what extent do perception and reflection share representational areas? To what extent are the control processes that select, maintain, and manipulate perceptual and reflective information subserved by common areas and networks? During perception and reflection, to what extent are common areas responsible for binding features together to create complex, episodic memories and for reviving them later? Considering similarities and differences in perceptual and reflective attention helps integrate a broad range of findings and raises important unresolved issues. PMID:22099456

Interference from familiar natural distractors is not eliminated by high perceptual load.

PubMed

He, Chunhong; Chen, Antao

2010-05-01

A crucial prediction of perceptual load theory is that high perceptual load can eliminate interference from distractors. However, Lavie et al. (Psychol Sci 14:510-515, 2003) found that high perceptual load did not eliminate interference when the distractor was a face. The current experiments examined the interaction between familiarity and perceptual load in modulating interference in a name search task. The data reveal that high perceptual load eliminated the interference effect for unfamiliar distractors that were faces or objects, but did not eliminate the interference for familiar distractors that were faces or objects. Based on these results, we proposed that the processing of familiar and natural stimuli may be immune to the effect of perceptual load.

Perceptually lossless fractal image compression

NASA Astrophysics Data System (ADS)

Lin, Huawu; Venetsanopoulos, Anastasios N.

1996-02-01

According to the collage theorem, the encoding distortion for fractal image compression is directly related to the metric used in the encoding process. In this paper, we introduce a perceptually meaningful distortion measure based on the human visual system's nonlinear response to luminance and the visual masking effects. Blackwell's psychophysical raw data on contrast threshold are first interpolated as a function of background luminance and visual angle, and are then used as an error upper bound for perceptually lossless image compression. For a variety of images, experimental results show that the algorithm produces a compression ratio of 8:1 to 10:1 without introducing visual artifacts.

Bilingual Infants Demonstrate Perceptual Flexibility in Phoneme Discrimination but Perceptual Constraint in Face Discrimination

PubMed Central

Singh, Leher; Loh, Darrell; Xiao, Naiqi G.

2017-01-01

Perceptual narrowing is a highly significant development associated with the first year of life. It conventionally refers to an orientation toward nativeness whereby infant's perceptual sensitivities begin to align with the phonetic properties of their native environment. Nativeness effects, such as perceptual narrowing, have been observed in several domains, most notably, in face discrimination within other-race faces and speech discrimination of non-native phonemes. Thus, far, nativeness effects in the face and speech perception have been theoretically linked, but have mostly been investigated independently. An important caveat to nativeness effects is that diversifying experiences, such as bilingualism or multiracial exposure, can lead to a reduction or postponement in attunement to the native environment. The present study was designed to investigate whether bilingualism influences nativeness effects in phonetic and face perception. Eleven-month-old monolingual and bilingual infants were tested on their abilities to discriminate native and non-native speech contrasts as well as own-race and other-race face contrasts. While monolingual infants demonstrated nativeness effects in face and speech perception, bilingual infants demonstrated nativeness effects in the face perception but demonstrated flexibility in speech perception. Results support domain-specific effects of bilingual experience on nativeness effects. PMID:28955278

Semantic Features, Perceptual Expectations, and Frequency as Factors in the Learning of Polar Spatial Adjective Concepts.

ERIC Educational Resources Information Center

Dunckley, Candida J. Lutes; Radtke, Robert C.

Two semantic theories of word learning, a perceptual complexity hypothesis (H. Clark, 1970) and a quantitative complexity hypothesis (E. Clark, 1972) were tested by teaching 24 preschoolers and 16 college students CVC labels for five polar spatial adjective concepts having single word representations in English, and for three having no direct…

Action video game play facilitates the development of better perceptual templates.

PubMed

Bejjanki, Vikranth R; Zhang, Ruyuan; Li, Renjie; Pouget, Alexandre; Green, C Shawn; Lu, Zhong-Lin; Bavelier, Daphne

2014-11-25

The field of perceptual learning has identified changes in perceptual templates as a powerful mechanism mediating the learning of statistical regularities in our environment. By measuring threshold-vs.-contrast curves using an orientation identification task under varying levels of external noise, the perceptual template model (PTM) allows one to disentangle various sources of signal-to-noise changes that can alter performance. We use the PTM approach to elucidate the mechanism that underlies the wide range of improvements noted after action video game play. We show that action video game players make use of improved perceptual templates compared with nonvideo game players, and we confirm a causal role for action video game play in inducing such improvements through a 50-h training study. Then, by adapting a recent neural model to this task, we demonstrate how such improved perceptual templates can arise from reweighting the connectivity between visual areas. Finally, we establish that action gamers do not enter the perceptual task with improved perceptual templates. Instead, although performance in action gamers is initially indistinguishable from that of nongamers, action gamers more rapidly learn the proper template as they experience the task. Taken together, our results establish for the first time to our knowledge the development of enhanced perceptual templates following action game play. Because such an improvement can facilitate the inference of the proper generative model for the task at hand, unlike perceptual learning that is quite specific, it thus elucidates a general learning mechanism that can account for the various behavioral benefits noted after action game play.

Action video game play facilitates the development of better perceptual templates

PubMed Central

Bejjanki, Vikranth R.; Zhang, Ruyuan; Li, Renjie; Pouget, Alexandre; Green, C. Shawn; Lu, Zhong-Lin; Bavelier, Daphne

2014-01-01

The field of perceptual learning has identified changes in perceptual templates as a powerful mechanism mediating the learning of statistical regularities in our environment. By measuring threshold-vs.-contrast curves using an orientation identification task under varying levels of external noise, the perceptual template model (PTM) allows one to disentangle various sources of signal-to-noise changes that can alter performance. We use the PTM approach to elucidate the mechanism that underlies the wide range of improvements noted after action video game play. We show that action video game players make use of improved perceptual templates compared with nonvideo game players, and we confirm a causal role for action video game play in inducing such improvements through a 50-h training study. Then, by adapting a recent neural model to this task, we demonstrate how such improved perceptual templates can arise from reweighting the connectivity between visual areas. Finally, we establish that action gamers do not enter the perceptual task with improved perceptual templates. Instead, although performance in action gamers is initially indistinguishable from that of nongamers, action gamers more rapidly learn the proper template as they experience the task. Taken together, our results establish for the first time to our knowledge the development of enhanced perceptual templates following action game play. Because such an improvement can facilitate the inference of the proper generative model for the task at hand, unlike perceptual learning that is quite specific, it thus elucidates a general learning mechanism that can account for the various behavioral benefits noted after action game play. PMID:25385590

Acoustic and perceptual characteristics of the voice in patients with vocal polyps after surgery and voice therapy.

PubMed

Petrovic-Lazic, Mirjana; Jovanovic, Nadica; Kulic, Milan; Babac, Snezana; Jurisic, Vladimir

2015-03-01

The aim of the study was to assess the effect of endolaryngeal phonomicrosurgery (EPM) and voice therapy in patients with vocal fold polyps using perceptual and acoustic analysis before and after both therapies. The acoustic tests and perceptual evaluation of voice were carried out on 41 female patients with vocal fold polyp before and after EPM and voice therapy. Both therapy strategies were performed. Used acoustic parameters were Jitter percent (Jitt), pitch perturbation quotient (PPQ), shimmer percent (Shim), amplitude perturbation quotient (APQ), fundamental frequency variation (vF0), noise-to-harmonic ratio (NHR), Voice Turbulence Index (VTI). For perceptual evaluation, GRB scale was used. Results indicated higher values of investigated parameters in patients' group than in the control group (P < 0.01). Good correlation between the perceptual hoarseness factors of GRB scale and objective acoustic voice parameters were observed. All analyzed acoustic parameters improved after the phonomicrosurgery and voice therapy and tend to approach to values of the control group. For Jitt percent, Shim percent, vF0, VTI, and NHR, there were statistically significant differences. Perceptual voice evaluation revealed statistically significantly (P < 0.01) decreased rating of G (grade), R (rough) and B (breathy) after surgery and voice therapy. Our data indicated that both acoustic and perceptual characteristic of voice in patients with vocal polyps significantly improved after phonomicrosurgical and voice treatment. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

The Role of Perceptual Load in Object Recognition

ERIC Educational Resources Information Center

Lavie, Nilli; Lin, Zhicheng; Zokaei, Nahid; Thoma, Volker

2009-01-01

Predictions from perceptual load theory (Lavie, 1995, 2005) regarding object recognition across the same or different viewpoints were tested. Results showed that high perceptual load reduces distracter recognition levels despite always presenting distracter objects from the same view. They also showed that the levels of distracter recognition were…

Patterns of Perceptual Motor Skills in First and Fourth Year Dental Students.

ERIC Educational Resources Information Center

Zullo, Thomas G.

A battery of perceptual motor skills tests was administered to 107 freshman and 84 senior dental students for the purposes of determining the factor structure of the battery and studying differences between the two groups. The tests used included Minnesota Rate of Manipulation Test (MRM), Placing and Turning; O'Connor Finger Dexterity; O'Connor…

Age Differences in Voice Evaluation: From Auditory-Perceptual Evaluation to Social Interactions

ERIC Educational Resources Information Center

Lortie, Catherine L.; Deschamps, Isabelle; Guitton, Matthieu J.; Tremblay, Pascale

2018-01-01

Purpose: The factors that influence the evaluation of voice in adulthood, as well as the consequences of such evaluation on social interactions, are not well understood. Here, we examined the effect of listeners' age and the effect of talker age, sex, and smoking status on the auditory-perceptual evaluation of voice, voice-related psychosocial…

Modeling trial by trial and block feedback in perceptual learning

PubMed Central

Liu, Jiajuan; Dosher, Barbara; Lu, Zhong-Lin

2014-01-01

Feedback has been shown to play a complex role in visual perceptual learning. It is necessary for performance improvement in some conditions while not others. Different forms of feedback, such as trial-by-trial feedback or block feedback, may both facilitate learning, but with different mechanisms. False feedback can abolish learning. We account for all these results with the Augmented Hebbian Reweight Model (AHRM). Specifically, three major factors in the model advance performance improvement: the external trial-by-trial feedback when available, the self-generated output as an internal feedback when no external feedback is available, and the adaptive criterion control based on the block feedback. Through simulating a comprehensive feedback study (Herzog & Fahle 1997, Vision Research, 37 (15), 2133–2141), we show that the model predictions account for the pattern of learning in seven major feedback conditions. The AHRM can fully explain the complex empirical results on the role of feedback in visual perceptual learning. PMID:24423783

Nutritional Factors Affecting Adult Neurogenesis and Cognitive Function.

PubMed

Poulose, Shibu M; Miller, Marshall G; Scott, Tammy; Shukitt-Hale, Barbara

2017-11-01

Adult neurogenesis, a complex process by which stem cells in the hippocampal brain region differentiate and proliferate into new neurons and other resident brain cells, is known to be affected by many intrinsic and extrinsic factors, including diet. Neurogenesis plays a critical role in neural plasticity, brain homeostasis, and maintenance in the central nervous system and is a crucial factor in preserving the cognitive function and repair of damaged brain cells affected by aging and brain disorders. Intrinsic factors such as aging, neuroinflammation, oxidative stress, and brain injury, as well as lifestyle factors such as high-fat and high-sugar diets and alcohol and opioid addiction, negatively affect adult neurogenesis. Conversely, many dietary components such as curcumin, resveratrol, blueberry polyphenols, sulforaphane, salvionic acid, polyunsaturated fatty acids (PUFAs), and diets enriched with polyphenols and PUFAs, as well as caloric restriction, physical exercise, and learning, have been shown to induce neurogenesis in adult brains. Although many of the underlying mechanisms by which nutrients and dietary factors affect adult neurogenesis have yet to be determined, nutritional approaches provide promising prospects to stimulate adult neurogenesis and combat neurodegenerative diseases and cognitive decline. In this review, we summarize the evidence supporting the role of nutritional factors in modifying adult neurogenesis and their potential to preserve cognitive function during aging. © 2017 American Society for Nutrition.

The Role of Perceptual Load in Inattentional Blindness

ERIC Educational Resources Information Center

Cartwright-Finch, Ula; Lavie, Nilli

2007-01-01

Perceptual load theory offers a resolution to the long-standing early vs. late selection debate over whether task-irrelevant stimuli are perceived, suggesting that irrelevant perception depends upon the perceptual load of task-relevant processing. However, previous evidence for this theory has relied on RTs and neuroimaging. Here we tested the…

The Effect of Perceptually Oriented Physical Education on Perceptual Motor Ability and Academic Ability of Kindergarten and First Grade Children.

ERIC Educational Resources Information Center

Davis, Robert G.

The effects of a perceptually oriented physical education program (PPE) on perceptual-motor ability and academic ability were studied using kindergarten and first-grade children. The four groups of kindergarten children varied the number of periods of PPE per week which then met--0, 1, 2, and 3 times per week. The four groups of first-grade…

The perceptual features of vocal fatigue as self-reported by a group of actors and singers.

PubMed

Kitch, J A; Oates, J

1994-09-01

Performers (10 actors/10 singers) rated via a self-report questionnaire the severity of their voice-related changes when vocally fatigued. Similar frequency patterns and perceptual features of vocal fatigue were found across subjects. Actors rated "power" aspects (e.g., voice projection) and singers rated vocal dynamic aspects (e.g., pitch range) of their voices as most affected when vocally fatigued. Vocal fatigue was evidenced by changes in kinesthetic/proprioceptive sensations and vocal dynamics. The causes and context of vocal fatigue were vocal misuse, being "run down," high performance demands, and using high pitch/volume levels. Further research is needed to delineate the perceptual features of "normal" levels of vocal fatigue and its possible causes.

Looking without Perceiving: Impaired Preattentive Perceptual Grouping in Autism Spectrum Disorder

PubMed Central

Carther-Krone, Tiffany A.; Shomstein, Sarah; Marotta, Jonathan J.

2016-01-01

Before becoming aware of a visual scene, our perceptual system has organized and selected elements in our environment to which attention should be allocated. Part of this process involves grouping perceptual features into a global whole. Individuals with autism spectrum disorders (ASD) rely on a more local processing strategy, which may be driven by difficulties perceptually grouping stimuli. We tested this notion using a line discrimination task in which two horizontal lines were superimposed on a background of black and white dots organized so that, on occasion, the dots induced the Ponzo illusion if perceptually grouped together. Results showed that even though neither group was aware of the illusion, the ASD group was significantly less likely than typically developing group to make perceptual judgments influenced by the illusion, revealing difficulties in preattentive grouping of visual stimuli. This may explain why individuals with ASD rely on local processing strategies, and offers new insight into the mechanism driving perceptual grouping in the typically developing human brain. PMID:27355678

Preferential processing of self-relevant stimuli occurs mainly at the perceptual and conscious stages of information processing.

PubMed

Tacikowski, P; Ehrsson, H H

2016-04-01

Self-related stimuli, such as one's own name or face, are processed faster and more accurately than other types of stimuli. However, what remains unknown is at which stage of the information processing hierarchy this preferential processing occurs. Our first aim was to determine whether preferential self-processing involves mainly perceptual stages or also post-perceptual stages. We found that self-related priming was stronger than other-related priming only because of perceptual prime-target congruency. Our second aim was to dissociate the role of conscious and unconscious factors in preferential self-processing. To this end, we compared the "self" and "other" conditions in trials where primes were masked or unmasked. In two separate experiments, we found that self-related priming was stronger than other-related priming but only in the unmasked trials. Together, our results suggest that preferential access to the self-concept occurs mainly at the perceptual and conscious stages of the stimulus processing hierarchy. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Kinematic cues in perceptual weight judgement and their origins in box lifting

PubMed Central

Hamilton, A.; Joyce, D. W.; Flanagan, R.; Frith, C. D.; Wolpert, D. M.

2009-01-01

When accepting a parcel from another person, we are able to use information about that person’s movement to estimate in advance the weight of the parcel, that is, to judge its weight from observed action. Perceptual weight judgment provides a powerful method to study our interpretation of other people’s actions, but it is not known what sources of information are used in judging weight. We have manipulated full form videos to obtain precise control of the perceived kinematics of a box lifting action, and use this technique to explore the kinematic cues that affect weight judgment. We find that observers rely most on the duration of the lifting movement to judge weight, and make less use of the durations of the grasp phase, when the box is first gripped, or the place phase, when the box is put down. These findings can be compared to the kinematics of natural box lifting behaviour, where we find that the duration of the grasp component is the best predictor of true box weight. The lack of accord between the optimal cues predicted by the natural behaviour and the cues actually used in the perceptual task has implications for our understanding of action observation in terms of a motor simulation. The differences between perceptual and motor behaviour are evidence against a strong version of the motor simulation hypothesis. PMID:16311765

Perceptual Averaging in Individuals with Autism Spectrum Disorder.

PubMed

Corbett, Jennifer E; Venuti, Paola; Melcher, David

2016-01-01

There is mounting evidence that observers rely on statistical summaries of visual information to maintain stable and coherent perception. Sensitivity to the mean (or other prototypical value) of a visual feature (e.g., mean size) appears to be a pervasive process in human visual perception. Previous studies in individuals diagnosed with Autism Spectrum Disorder (ASD) have uncovered characteristic patterns of visual processing that suggest they may rely more on enhanced local representations of individual objects instead of computing such perceptual averages. To further explore the fundamental nature of abstract statistical representation in visual perception, we investigated perceptual averaging of mean size in a group of 12 high-functioning individuals diagnosed with ASD using simplified versions of two identification and adaptation tasks that elicited characteristic perceptual averaging effects in a control group of neurotypical participants. In Experiment 1, participants performed with above chance accuracy in recalling the mean size of a set of circles ( mean task ) despite poor accuracy in recalling individual circle sizes ( member task ). In Experiment 2, their judgments of single circle size were biased by mean size adaptation. Overall, these results suggest that individuals with ASD perceptually average information about sets of objects in the surrounding environment. Our results underscore the fundamental nature of perceptual averaging in vision, and further our understanding of how autistic individuals make sense of the external environment.

Minimalist approach to perceptual interactions.

PubMed

Lenay, Charles; Stewart, John

2012-01-01

WORK AIMED AT STUDYING SOCIAL COGNITION IN AN INTERACTIONIST PERSPECTIVE OFTEN ENCOUNTERS SUBSTANTIAL THEORETICAL AND METHODOLOGICAL DIFFICULTIES: identifying the significant behavioral variables; recording them without disturbing the interaction; and distinguishing between: (a) the necessary and sufficient contributions of each individual partner for a collective dynamics to emerge; (b) features which derive from this collective dynamics and escape from the control of the individual partners; and (c) the phenomena arising from this collective dynamics which are subsequently appropriated and used by the partners. We propose a minimalist experimental paradigm as a basis for this conceptual discussion: by reducing the sensory inputs to a strict minimum, we force a spatial and temporal deployment of the perceptual activities, which makes it possible to obtain a complete recording and control of the dynamics of interaction. After presenting the principles of this minimalist approach to perception, we describe a series of experiments on two major questions in social cognition: recognizing the presence of another intentional subject; and phenomena of imitation. In both cases, we propose explanatory schema which render an interactionist approach to social cognition clear and explicit. Starting from our earlier work on perceptual crossing we present a new experiment on the mechanisms of reciprocal recognition of the perceptual intentionality of the other subject: the emergent collective dynamics of the perceptual crossing can be appropriated by each subject. We then present an experimental study of opaque imitation (when the subjects cannot see what they themselves are doing). This study makes it possible to characterize what a properly interactionist approach to imitation might be. In conclusion, we draw on these results, to show how an interactionist approach can contribute to a fully social approach to social cognition.

Minimalist Approach to Perceptual Interactions

PubMed Central

Lenay, Charles; Stewart, John

2012-01-01

Work aimed at studying social cognition in an interactionist perspective often encounters substantial theoretical and methodological difficulties: identifying the significant behavioral variables; recording them without disturbing the interaction; and distinguishing between: (a) the necessary and sufficient contributions of each individual partner for a collective dynamics to emerge; (b) features which derive from this collective dynamics and escape from the control of the individual partners; and (c) the phenomena arising from this collective dynamics which are subsequently appropriated and used by the partners. We propose a minimalist experimental paradigm as a basis for this conceptual discussion: by reducing the sensory inputs to a strict minimum, we force a spatial and temporal deployment of the perceptual activities, which makes it possible to obtain a complete recording and control of the dynamics of interaction. After presenting the principles of this minimalist approach to perception, we describe a series of experiments on two major questions in social cognition: recognizing the presence of another intentional subject; and phenomena of imitation. In both cases, we propose explanatory schema which render an interactionist approach to social cognition clear and explicit. Starting from our earlier work on perceptual crossing we present a new experiment on the mechanisms of reciprocal recognition of the perceptual intentionality of the other subject: the emergent collective dynamics of the perceptual crossing can be appropriated by each subject. We then present an experimental study of opaque imitation (when the subjects cannot see what they themselves are doing). This study makes it possible to characterize what a properly interactionist approach to imitation might be. In conclusion, we draw on these results, to show how an interactionist approach can contribute to a fully social approach to social cognition. PMID:22582041

SECOND-ORDER PROBLEMS IN STUDIES OF PERCEPTUAL DEVELOPMENT.

ERIC Educational Resources Information Center

WHITE, BURTON L.

RECENT RESEARCH FINDINGS ON THE PERCEPTUAL DEVELOPMENT OF YOUNG INFANTS WERE SURVEYED, AND THE NEED FOR SYNTHESIZING THESE NEW FINDINGS INTO WORKABLE CONCEPTS WAS SUGGESTED FOR THE FRUITFUL STUDY OF HIGHER ORDER CONSIDERATIONS IN THE FUTURE. A DISCUSSION WAS MADE ON THE DEVELOPMENTAL ISSUES OF--(1) SUPERORDINATE CATEGORIES OF PERCEPTUAL FUNCTION,…

The Role of Response Bias in Perceptual Learning

ERIC Educational Resources Information Center

Jones, Pete R.; Moore, David R.; Shub, Daniel E.; Amitay, Sygal

2015-01-01

Sensory judgments improve with practice. Such perceptual learning is often thought to reflect an increase in perceptual sensitivity. However, it may also represent a decrease in response bias, with unpracticed observers acting in part on a priori hunches rather than sensory evidence. To examine whether this is the case, 55 observers practiced…

Neural substrates of perceptual integration during bistable object perception

PubMed Central

Flevaris, Anastasia V.; Martínez, Antigona; Hillyard, Steven A.

2013-01-01

The way we perceive an object depends both on feedforward, bottom-up processing of its physical stimulus properties and on top-down factors such as attention, context, expectation, and task relevance. Here we compared neural activity elicited by varying perceptions of the same physical image—a bistable moving image in which perception spontaneously alternates between dissociated fragments and a single, unified object. A time-frequency analysis of EEG changes associated with the perceptual switch from object to fragment and vice versa revealed a greater decrease in alpha (8–12 Hz) accompanying the switch to object percept than to fragment percept. Recordings of event-related potentials elicited by irrelevant probes superimposed on the moving image revealed an enhanced positivity between 184 and 212 ms when the probes were contained within the boundaries of the perceived unitary object. The topography of the positivity (P2) in this latency range elicited by probes during object perception was distinct from the topography elicited by probes during fragment perception, suggesting that the neural processing of probes differed as a function of perceptual state. Two source localization algorithms estimated the neural generator of this object-related difference to lie in the lateral occipital cortex, a region long associated with object perception. These data suggest that perceived objects attract attention, incorporate visual elements occurring within their boundaries into unified object representations, and enhance the visual processing of elements occurring within their boundaries. Importantly, the perceived object in this case emerged as a function of the fluctuating perceptual state of the viewer. PMID:24246467

Effects of regular aerobic exercise on visual perceptual learning.

PubMed

Connell, Charlotte J W; Thompson, Benjamin; Green, Hayden; Sullivan, Rachel K; Gant, Nicholas

2017-12-02

This study investigated the influence of five days of moderate intensity aerobic exercise on the acquisition and consolidation of visual perceptual learning using a motion direction discrimination (MDD) task. The timing of exercise relative to learning was manipulated by administering exercise either before or after perceptual training. Within a matched-subjects design, twenty-seven healthy participants (n = 9 per group) completed five consecutive days of perceptual training on a MDD task under one of three interventions: no exercise, exercise before the MDD task, or exercise after the MDD task. MDD task accuracy improved in all groups over the five-day period, but there was a trend for impaired learning when exercise was performed before visual perceptual training. MDD task accuracy (mean ± SD) increased in exercise before by 4.5 ± 6.5%; exercise after by 11.8 ± 6.4%; and no exercise by 11.3 ± 7.2%. All intervention groups displayed similar MDD threshold reductions for the trained and untrained motion axes after training. These findings suggest that moderate daily exercise does not enhance the rate of visual perceptual learning for an MDD task or the transfer of learning to an untrained motion axis. Furthermore, exercise performed immediately prior to a visual perceptual learning task may impair learning. Further research with larger groups is required in order to better understand these effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Processing Capacity under Perceptual and Cognitive Load: A Closer Look at Load Theory

ERIC Educational Resources Information Center

Fitousi, Daniel; Wenger, Michael J.

2011-01-01

Variations in perceptual and cognitive demands (load) play a major role in determining the efficiency of selective attention. According to load theory (Lavie, Hirst, Fockert, & Viding, 2004) these factors (a) improve or hamper selectivity by altering the way resources (e.g., processing capacity) are allocated, and (b) tap resources rather than…

Factors affecting dignity of patients with multiple sclerosis.

PubMed

Sharifi, Simin; Borhani, Fariba; Abbaszadeh, Abbas

2016-12-01

MS is one of the most common chronic diseases of the nervous system. Apart from disease progression, other complications such as unemployment, separation and divorce could potentially threat patients' dignity. Most of the previous studies have been done of maintaining patients' dignity in interaction with healthcare team, but studies on affecting factors of dignity in chronic patients in the society and in interaction with usual people are scarce. We aimed to investigate factors affecting dignity of Iranian patients with MS in daily living and in interaction of them with the society. In this qualitative study, 13 patients with multiple sclerosis were chosen by purposive sampling and semi-structured interviews were conducted until data saturation. The study was done in Tehran, the capital city of Iran. Factors affecting dignity were classified as 'personal factors' and 'social factors'. Personal factors consist of the following subcategories: patients' communication with self, patients' knowledge, patients' values and beliefs and patients' resources. Social factors include others' communication with patients, social knowledge, social values and beliefs and social resources. Multiple personal and social factors interfere in perceived patient dignity. In fact, interaction between personal and social factors can be influential in final perceived dignity. By focusing on whole aspects of the patients' lives, we can identify dignity-promoting or dignity-threatening factors and help patients maintain their dignity by taking appropriate measures for moderating threatening factors and improving dignity enhancing ones. © 2016 Nordic College of Caring Science.

Perceptual Biases in Relation to Paranormal and Conspiracy Beliefs.

PubMed

van Elk, Michiel

2015-01-01

Previous studies have shown that one's prior beliefs have a strong effect on perceptual decision-making and attentional processing. The present study extends these findings by investigating how individual differences in paranormal and conspiracy beliefs are related to perceptual and attentional biases. Two field studies were conducted in which visitors of a paranormal conducted a perceptual decision making task (i.e. the face/house categorization task; Experiment 1) or a visual attention task (i.e. the global/local processing task; Experiment 2). In the first experiment it was found that skeptics compared to believers more often incorrectly categorized ambiguous face stimuli as representing a house, indicating that disbelief rather than belief in the paranormal is driving the bias observed for the categorization of ambiguous stimuli. In the second experiment, it was found that skeptics showed a classical 'global-to-local' interference effect, whereas believers in conspiracy theories were characterized by a stronger 'local-to-global interference effect'. The present study shows that individual differences in paranormal and conspiracy beliefs are associated with perceptual and attentional biases, thereby extending the growing body of work in this field indicating effects of cultural learning on basic perceptual processes.

Recalibration in functional perceptual-motor tasks: A systematic review.

PubMed

Brand, Milou Tessa; de Oliveira, Rita Ferraz

2017-12-01

Skilled actions are the result of a perceptual-motor system being well-calibrated to the appropriate information variables. Changes to the perceptual or motor system initiates recalibration, which is the rescaling of the perceptual-motor system to informational variables. For example, a professional baseball player may need to rescale their throws due to fatigue. The aim of this systematic review is to analyse how recalibration can and has been measured and also to evaluate the literature on recalibration. Five databases were systematically screened to identify literature that reported experiments where a disturbance was applied to the perceptual-motor system in functional perceptual-motor tasks. Each of the 91 experiments reported the immediate effects of a disturbance and/or the effects of removing that disturbance after recalibration. The results showed that experiments applied disturbances to either perception or action, and used either direct or indirect measures of recalibration. In contrast with previous conclusions, active exploration was only sufficient for fast recalibration when the relevant information source was available. Further research into recalibration mechanisms should include the study of information sources as well as skill expertise. Copyright © 2017 Elsevier B.V. All rights reserved.

Harnessing the wandering mind: the role of perceptual load.

PubMed

Forster, Sophie; Lavie, Nilli

2009-06-01

Perceptual load is a key determinant of distraction by task-irrelevant stimuli (e.g., Lavie, N. (2005). Distracted and confused?: Selective attention under load. Trends in Cognitive Sciences, 9, 75-82). Here we establish the role of perceptual load in determining an internal form of distraction by task-unrelated thoughts (TUTs or "mind-wandering"). Four experiments demonstrated reduced frequency of TUTs with high compared to low perceptual load in a visual-search task. Alternative accounts in terms of increased demands on responses, verbal working memory or motivation were ruled out and clear effects of load were found for unintentional TUTs. Individual differences in load effects on internal (TUTs) and external (response-competition) distractors were correlated. These results suggest that exhausting attentional capacity in task-relevant processing under high perceptual load can reduce processing of task-irrelevant information from external and internal sources alike.

Sensory and Perceptual Functions in the Cerebral Palsied. III. Some Visual Perceptual Relationships

ERIC Educational Resources Information Center

Breakey, Arnold Stewart; And Others

1974-01-01

The relationships between specific aspects of peripheral ocular defects and perceptual deficits were investigated in a cerebral palsied population of 60 spastics, 60 athetoids, and 60 non-neurologically impaired Ss, 7 to 21 years of age. (Author/MC)

Specificity of perceptual processing in rereading spatially transformed materials.

PubMed

Horton, K D; McKenzie, B D

1995-05-01

While most studies using the task of reading spatially transformed text do not reveal evidence of specific perceptual transfer, a study by Masson (1986, Experiment 3) provides clear evidence of such effects. Several experiments were designed to identify the basis for this empirical discrepancy. The only substantive evidence of specific perceptual transfer occurred when the words were presented in an unfamiliar typography, although each study suggested a trend toward perceptual specificity effects. The results are discussed in terms of Graf and Ryan's (1990) ideas about the role of distinctive memory representations.

Visible digital watermarking system using perceptual models

NASA Astrophysics Data System (ADS)

Cheng, Qiang; Huang, Thomas S.

2001-03-01

This paper presents a visible watermarking system using perceptual models. %how and why A watermark image is overlaid translucently onto a primary image, for the purposes of immediate claim of copyright, instantaneous recognition of owner or creator, or deterrence to piracy of digital images or video. %perceptual The watermark is modulated by exploiting combined DCT-domain and DWT-domain perceptual models. % so that the watermark is visually uniform. The resulting watermarked image is visually pleasing and unobtrusive. The location, size and strength of the watermark vary randomly with the underlying image. The randomization makes the automatic removal of the watermark difficult even though the algorithm is known publicly but the key to the random sequence generator. The experiments demonstrate that the watermarked images have pleasant visual effect and strong robustness. The watermarking system can be used in copyright notification and protection.

Race-specific perceptual discrimination improvement following short individuation training with faces

PubMed Central

McGugin, Rankin Williams; Tanaka, James W.; Lebrecht, Sophie; Tarr, Michael J.; Gauthier, Isabel

2010-01-01

This study explores the effect of individuation training on the acquisition of race-specific expertise. First, we investigated whether practice individuating other-race faces yields improvement in perceptual discrimination for novel faces of that race. Second, we asked whether there was similar improvement for novel faces of a different race for which participants received equal practice, but in an orthogonal task that did not require individuation. Caucasian participants were trained to individuate faces of one race (African American or Hispanic) and to make difficult eye luminance judgments on faces of the other race. By equating these tasks we are able to rule out raw experience, visual attention or performance/success-induced positivity as the critical factors that produce race-specific improvements. These results indicate that individuation practice is one mechanism through which cognitive, perceptual, and/or social processes promote growth of the own-race face recognition advantage. PMID:21429002

Dissociation between perceptual processing and priming in long-term lorazepam users.

PubMed

Giersch, Anne; Vidailhet, Pierre

2006-12-01

Acute effects of lorazepam on visual information processing, perceptual priming and explicit memory are well established. However, visual processing and perceptual priming have rarely been explored in long-term lorazepam users. By exploring these functions it was possible to test the hypothesis that difficulty in processing visual information may lead to deficiencies in perceptual priming. Using a simple blind procedure, we tested explicit memory, perceptual priming and visual perception in 15 long-term lorazepam users and 15 control subjects individually matched according to sex, age and education level. Explicit memory, perceptual priming, and the identification of fragmented pictures were found to be preserved in long-term lorazepam users, contrary to what is usually observed after an acute drug intake. The processing of visual contour, on the other hand, was still significantly impaired. These results suggest that the effects observed on low-level visual perception are independent of the acute deleterious effects of lorazepam on perceptual priming. A comparison of perceptual priming in subjects with low- vs. high-level identification of new fragmented pictures further suggests that the ability to identify fragmented pictures has no influence on priming. Despite the fact that they were treated with relatively low doses and far from peak plasma concentration, it is noteworthy that in long-term users memory was preserved.

Selective attention to task-irrelevant emotional distractors is unaffected by the perceptual load associated with a foreground task.

PubMed

Hindi Attar, Catherine; Müller, Matthias M

2012-01-01

A number of studies have shown that emotionally arousing stimuli are preferentially processed in the human brain. Whether or not this preference persists under increased perceptual load associated with a task at hand remains an open question. Here we manipulated two possible determinants of the attentional selection process, perceptual load associated with a foreground task and the emotional valence of concurrently presented task-irrelevant distractors. As a direct measure of sustained attentional resource allocation in early visual cortex we used steady-state visual evoked potentials (SSVEPs) elicited by distinct flicker frequencies of task and distractor stimuli. Subjects either performed a detection (low load) or discrimination (high load) task at a centrally presented symbol stream that flickered at 8.6 Hz while task-irrelevant neutral or unpleasant pictures from the International Affective Picture System (IAPS) flickered at a frequency of 12 Hz in the background of the stream. As reflected in target detection rates and SSVEP amplitudes to both task and distractor stimuli, unpleasant relative to neutral background pictures more strongly withdrew processing resources from the foreground task. Importantly, this finding was unaffected by the factor 'load' which turned out to be a weak modulator of attentional processing in human visual cortex.

Dimension-based statistical learning affects both speech perception and production

PubMed Central

Lehet, Matthew; Holt, Lori L.

2016-01-01

Multiple acoustic dimensions signal speech categories. However, dimensions vary in their informativeness; some are more diagnostic of category membership than others. Speech categorization reflects these dimensional regularities such that diagnostic dimensions carry more “perceptual weight” and more effectively signal category membership to native listeners. Yet, perceptual weights are malleable. When short-term experience deviates from long-term language norms, such as in a foreign accent, the perceptual weight of acoustic dimensions in signaling speech category membership rapidly adjusts. The present study investigated whether rapid adjustments in listeners’ perceptual weights in response to speech that deviates from the norms also affects listeners’ own speech productions. In a word recognition task, the correlation between two acoustic dimensions signaling consonant categories, fundamental frequency (F0) and voice onset time (VOT), matched the correlation typical of English, then shifted to an “artificial accent” that reversed the relationship, and then shifted back. Brief, incidental exposure to the artificial accent caused participants to down-weight perceptual reliance on F0, consistent with previous research. Throughout the task, participants were intermittently prompted with pictures to produce these same words. In the block in which listeners heard the artificial accent with a reversed F0 x VOT correlation, F0 was a less robust cue to voicing in listeners’ own speech productions. The statistical regularities of short-term speech input affect both speech perception and production, as evidenced via shifts in how acoustic dimensions are weighted. PMID:27666146

Visual perceptual skills in children born with very low birth weights.

PubMed

Davis, Deborah Winders; Burns, Barbara M; Wilkerson, Shirley A; Steichen, Jean J

2005-01-01

A disproportionate number of very low birth weight (VLBW; < or =1500 g) children require special education services and have school-related problems even when they are free from major disabilities and have average intelligence quotient scores. Visual-perceptual problems have been suggested as contributors to deficits in academic performance, but few data are available describing specific visual-perceptual problems. This study was designed to identify specific visual-perceptual skills in VLBW children. Participants were 92 VLBW children aged 4 through 5 years who were free from major disability and appropriate for gestational age at birth. The Test of Visual-Perceptual Skills (non-motor)-Revised was used. Despite intelligent quotient scores in the average range, the majority (63% to 78.3%) of the children performed below age level on all seven subscales of a normed assessment of visual perceptual skills. Results suggest that visual perceptual screening should be considered as a part of routine evaluations of preschool-aged children born prematurely. Early identification of specific deficits could lead to interventions to improve achievement trajectories for these high-risk children.

Perceptual learning in children with visual impairment improves near visual acuity.

PubMed

Huurneman, Bianca; Boonstra, F Nienke; Cox, Ralf F A; van Rens, Ger; Cillessen, Antonius H N

2013-09-17

This study investigated whether visual perceptual learning can improve near visual acuity and reduce foveal crowding effects in four- to nine-year-old children with visual impairment. Participants were 45 children with visual impairment and 29 children with normal vision. Children with visual impairment were divided into three groups: a magnifier group (n = 12), a crowded perceptual learning group (n = 18), and an uncrowded perceptual learning group (n = 15). Children with normal vision also were divided in three groups, but were measured only at baseline. Dependent variables were single near visual acuity (NVA), crowded NVA, LH line 50% crowding NVA, number of trials, accuracy, performance time, amount of small errors, and amount of large errors. Children with visual impairment trained during six weeks, two times per week, for 30 minutes (12 training sessions). After training, children showed significant improvement of NVA in addition to specific improvements on the training task. The crowded perceptual learning group showed the largest acuity improvements (1.7 logMAR lines on the crowded chart, P < 0.001). Only the children in the crowded perceptual learning group showed improvements on all NVA charts. Children with visual impairment benefit from perceptual training. While task-specific improvements were observed in all training groups, transfer to crowded NVA was largest in the crowded perceptual learning group. To our knowledge, this is the first study to provide evidence for the improvement of NVA by perceptual learning in children with visual impairment. (http://www.trialregister.nl number, NTR2537.).

Evidence accumulation detected in BOLD signal using slow perceptual decision making.

PubMed

Krueger, Paul M; van Vugt, Marieke K; Simen, Patrick; Nystrom, Leigh; Holmes, Philip; Cohen, Jonathan D

2017-04-01

We assessed whether evidence accumulation could be observed in the BOLD signal during perceptual decision making. This presents a challenge since the hemodynamic response is slow, while perceptual decisions are typically fast. Guided by theoretical predictions of the drift diffusion model, we slowed down decisions by penalizing participants for incorrect responses. Second, we distinguished BOLD activity related to stimulus detection (modeled using a boxcar) from activity related to integration (modeled using a ramp) by minimizing the collinearity of GLM regressors. This was achieved by dissecting a boxcar into its two most orthogonal components: an "up-ramp" and a "down-ramp." Third, we used a control condition in which stimuli and responses were similar to the experimental condition, but that did not engage evidence accumulation of the stimuli. The results revealed an absence of areas in parietal cortex that have been proposed to drive perceptual decision making but have recently come into question; and newly identified regions that are candidates for involvement in evidence accumulation. Previous fMRI studies have either used fast perceptual decision making, which precludes the measurement of evidence accumulation, or slowed down responses by gradually revealing stimuli. The latter approach confounds perceptual detection with evidence accumulation because accumulation is constrained by perceptual input. We slowed down the decision making process itself while leaving perceptual information intact. This provided a more sensitive and selective observation of brain regions associated with the evidence accumulation processes underlying perceptual decision making than previous methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Acoustic Properties of the Voice Source and the Vocal Tract: Are They Perceptually Independent?

PubMed

Erickson, Molly L

2016-11-01

This study sought to determine whether the properties of the voice source and vocal tract are perceptually independent. Within-subjects design. This study employed a paired-comparison paradigm where listeners heard synthetic voices and rated them as same or different using a visual analog scale. Stimuli were synthesized using three different source slopes and two different formant patterns (mezzo-soprano and soprano) on the vowel /a/ at four pitches: A3, C4, B4, and F5. Whereas formant pattern was the strongest effect, difference in source slope also affected perceived quality difference. Source slope and formant pattern were not independently perceived. These results suggest that when judging laryngeal adduction using perceptual information, judgments may not be accurate when the stimuli are of differing formant patterns. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Investigating the mixture and subdivision of perceptual and conceptual processing in Japanese memory tests.

PubMed

Gabeza, R

1995-03-01

The dual nature of the Japanese writing system was used to investigate two assumptions of the processing view of memory transfer: (1) that both perceptual and conceptual processing can contribute to the same memory test (mixture assumption) and (2) that both can be broken into more specific processes (subdivision assumption). Supporting the mixture assumption, a word fragment completion test based on ideographic kanji characters (kanji fragment completion test) was affected by both perceptual (hiragana/kanji script shift) and conceptual (levels-of-processing) study manipulations kanji fragments, because it did not occur with the use of meaningless hiragana fragments. The mixture assumption is also supported by an effect of study script on an implicit conceptual test (sentence completion), and the subdivision assumption is supported by a crossover dissociation between hiragana and kanji fragment completion as a function of study script.

Acoustic and perceptual aspects of vocal function in children with adenotonsillar hypertrophy--effects of surgery.

PubMed

Lundeborg, Inger; Hultcrantz, Elisabeth; Ericsson, Elisabeth; McAllister, Anita

2012-07-01

To evaluate outcome of two types of tonsil surgery (tonsillectomy [TE]+adenoidectomy or tonsillotomy [TT]+adenoidectomy) on vocal function perceptually and acoustically. Sixty-seven children, aged 50-65 months, on waiting list for tonsil surgery were randomized to TE (n=33) or TT (n=34). Fifty-seven age- and gender-matched healthy preschool children were controls. Twenty-eight of them, aged 48-59 months, served as control group before surgery, and 29, aged 60-71 months, served as control group after surgery. Before surgery and 6 months postoperatively, the children were recorded producing three sustained vowels (/ɑ/, /u/, and /i/) and 14 words. The control groups were recorded only once. Three trained speech and language pathologists performed the perceptual analysis using visual analog scale for eight voice quality parameters. Acoustic analysis from sustained vowels included average fundamental frequency, jitter percent, shimmer percent, noise-to-harmonic ratio, and the center frequencies of formants 1-3. Before surgery, the children were rated to have more hyponasality and compressed/throaty voice (P<0.05) and lower mean pitch (P<0.01) in comparison to the control group. They also had higher perturbation measures and lower frequencies of the second and third formants. After surgery, there were no differences perceptually. Perturbation measures decreased but were still higher compared with those of control group (P<0.05). Differences in formant frequencies for /i/ and /u/ remained. No differences were found between the two surgical methods. Voice quality is affected perceptually and acoustically by adenotonsillar hypertrophy. After surgery, the voice is perceptually normalized but acoustic differences remain. Outcome was equal for both surgical methods. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Limited Cognitive Resources Explain a Trade-Off between Perceptual and Metacognitive Vigilance.

PubMed

Maniscalco, Brian; McCurdy, Li Yan; Odegaard, Brian; Lau, Hakwan

2017-02-01

Why do experimenters give subjects short breaks in long behavioral experiments? Whereas previous studies suggest it is difficult to maintain attention and vigilance over long periods of time, it is unclear precisely what mechanisms benefit from rest after short experimental blocks. Here, we evaluate decline in both perceptual performance and metacognitive sensitivity (i.e., how well confidence ratings track perceptual decision accuracy) over time and investigate whether characteristics of prefrontal cortical areas correlate with these measures. Whereas a single-process signal detection model predicts that these two forms of fatigue should be strongly positively correlated, a dual-process model predicts that rates of decline may dissociate. Here, we show that these measures consistently exhibited negative or near-zero correlations, as if engaged in a trade-off relationship, suggesting that different mechanisms contribute to perceptual and metacognitive decisions. Despite this dissociation, the two mechanisms likely depend on common resources, which could explain their trade-off relationship. Based on structural MRI brain images of individual human subjects, we assessed gray matter volume in the frontal polar area, a region that has been linked to visual metacognition. Variability of frontal polar volume correlated with individual differences in behavior, indicating the region may play a role in supplying common resources for both perceptual and metacognitive vigilance. Additional experiments revealed that reduced metacognitive demand led to superior perceptual vigilance, providing further support for this hypothesis. Overall, results indicate that during breaks between short blocks, it is the higher-level perceptual decision mechanisms, rather than lower-level sensory machinery, that benefit most from rest. Perceptual task performance declines over time (the so-called vigilance decrement), but the relationship between vigilance in perception and metacognition has

Can Attention be Divided Between Perceptual Groups?

NASA Technical Reports Server (NTRS)

McCann, Robert S.; Foyle, David C.; Johnston, James C.; Hart, Sandra G. (Technical Monitor)

1994-01-01

Previous work using Head-Up Displays (HUDs) suggests that the visual system parses the HUD and the outside world into distinct perceptual groups, with attention deployed sequentially to first one group and then the other. New experiments show that both groups can be processed in parallel in a divided attention search task, even though subjects have just processed a stimulus in one perceptual group or the other. Implications for models of visual attention will be discussed.

Predictors of Sensitivity to Perceptual Learning in Children With Infantile Nystagmus.

PubMed

Huurneman, Bianca; Boonstra, F Nienke; Goossens, Jeroen

2017-08-01

To identify predictors of sensitivity to perceptual learning on a computerized, near-threshold letter discrimination task in children with infantile nystagmus (idiopathic IN: n = 18; oculocutaneous albinism accompanied by IN: n = 18). Children were divided into two age-, acuity-, and diagnosis-matched training groups: a crowded (n = 18) and an uncrowded training group (n = 18). Training consisted of 10 sessions spread out over 5 weeks (grand total of 3500 trials). Baseline performance, age, diagnosis, training condition, and perceived pleasantness of training (training joy) were entered as linear regression predictors of training-induced changes on a single- and a crowded-letter task. An impressive 57% of the variability in improvements of single-letter visual acuity was explained by age, training condition, and training joy. Being older and training with uncrowded letters were associated with larger single-letter visual acuity improvements. More training joy was associated with a larger gain from the uncrowded training and a smaller gain from the crowded training. Fifty-six percent of the variability in crowded-letter task improvements was explained by baseline performance, age, diagnosis, and training condition. After regressing out the variability induced by training condition, baseline performance, and age, perceptual learning proved more effective for children with idiopathic IN than for children with albinism accompanied by IN. Training gains increased with poorer baseline performance in idiopaths, but not in children with albinism accompanied by IN. Age and baseline performance, but not training joy, are important prognostic factors for the effect of perceptual learning in children with IN. However, their predictive value for achieving improvements in single-letter acuity and crowded letter acuity, respectively, differs between diagnostic subgroups and training condition. These findings may help with personalized treatment of individuals likely to benefit

Perceptual Learning in Children With Infantile Nystagmus: Effects on Reading Performance.

PubMed

Huurneman, Bianca; Boonstra, F Nienke; Goossens, Jeroen

2016-08-01

Perceptual learning improves visual acuity and reduces crowding in children with infantile nystagmus (IN). Here, we compare reading performance of 6- to 11-year-old children with IN with normal controls, and evaluate whether perceptual learning improves their reading. Children with IN were divided in two training groups: a crowded training group (n = 18; albinism: n = 8; idiopathic IN: n = 10) and an uncrowded training group (n = 17; albinism: n = 9; idiopathic IN: n = 8). Also 11 children with normal vision participated. Outcome measures were: reading acuity (the smallest readable font size), maximum reading speed, critical print size (font size below which reading is suboptimal), and acuity reserve (difference between reading acuity and critical print size). We used multiple regression analyses to test if these reading parameters were related to the children's uncrowded distance acuity and/or crowding scores. Reading acuity and critical print size were 0.65 ± 0.04 and 0.69 ± 0.08 log units larger for children with IN than for children with normal vision. Maximum reading speed and acuity reserve did not differ between these groups. After training, reading acuity improved by 0.12 ± 0.02 logMAR and critical print size improved by 0.11 ± 0.04 logMAR in both IN training groups. The changes in reading acuity, critical print size, and acuity reserve of children with IN were tightly related to changes in their uncrowded distance acuity and the changes in magnitude and extent of crowding. Our findings are the first to show that visual acuity is not the only factor that restricts reading in children with IN, but that crowding also limits their reading performance. By targeting both of these spatial bottlenecks in children with IN, our perceptual learning paradigms significantly improved their reading acuity and critical print size. This shows that perceptual learning can effectively transfer to reading.

Perceptual and Cognitive Impairments and Driving

PubMed Central

Korner-Bitensky, Nicol; Coopersmith, Henry; Mayo, Nancy; Leblanc, Ginette; Kaizer, Franceen

1990-01-01

Perceptual and cognitive disorders that frequently accompany stroke and head injury influence an individual's ability to drive a motor vehicle. Canadian physicians are legally responsible for identifying patients who are potentially unsafe to drive and, if they fail to do so, may be held liable in a civil action suit. The authors review the guidelines for physicians evaluating a patient's fitness to drive after brain injury. They also examine the actions a physician should take when a patient with perceptual and cognitive problems wants to drive. Ultimately, by taking these actions, physicians will help to prevent driving accidents. PMID:21234047

A perceptual account of symbolic reasoning

PubMed Central

Landy, David; Allen, Colin; Zednik, Carlos

2014-01-01

People can be taught to manipulate symbols according to formal mathematical and logical rules. Cognitive scientists have traditionally viewed this capacity—the capacity for symbolic reasoning—as grounded in the ability to internally represent numbers, logical relationships, and mathematical rules in an abstract, amodal fashion. We present an alternative view, portraying symbolic reasoning as a special kind of embodied reasoning in which arithmetic and logical formulae, externally represented as notations, serve as targets for powerful perceptual and sensorimotor systems. Although symbolic reasoning often conforms to abstract mathematical principles, it is typically implemented by perceptual and sensorimotor engagement with concrete environmental structures. PMID:24795662

High perceptual load leads to both reduced gain and broader orientation tuning

PubMed Central

Stolte, Moritz; Bahrami, Bahador; Lavie, Nilli

2014-01-01

Due to its limited capacity, visual perception depends on the allocation of attention. The resultant phenomena of inattentional blindness, accompanied by reduced sensory visual cortex response to unattended stimuli in conditions of high perceptual load in the attended task, are now well established (Lavie, 2005; Lavie, 2010, for reviews). However, the underlying mechanisms for these effects remain to be elucidated. Specifically, is reduced perceptual processing under high perceptual load a result of reduced sensory signal gain, broader tuning, or both? We examined this question with psychophysical measures of orientation tuning under different levels of perceptual load in the task performed. Our results show that increased perceptual load leads to both reduced sensory signal and broadening of tuning. These results clarify the effects of attention on elementary visual perception and suggest that high perceptual load is critical for attentional effects on sensory tuning. PMID:24610952

Perceptual Biases in Relation to Paranormal and Conspiracy Beliefs

PubMed Central

van Elk, Michiel

2015-01-01

Previous studies have shown that one’s prior beliefs have a strong effect on perceptual decision-making and attentional processing. The present study extends these findings by investigating how individual differences in paranormal and conspiracy beliefs are related to perceptual and attentional biases. Two field studies were conducted in which visitors of a paranormal conducted a perceptual decision making task (i.e. the face / house categorization task; Experiment 1) or a visual attention task (i.e. the global / local processing task; Experiment 2). In the first experiment it was found that skeptics compared to believers more often incorrectly categorized ambiguous face stimuli as representing a house, indicating that disbelief rather than belief in the paranormal is driving the bias observed for the categorization of ambiguous stimuli. In the second experiment, it was found that skeptics showed a classical ‘global-to-local’ interference effect, whereas believers in conspiracy theories were characterized by a stronger ‘local-to-global interference effect’. The present study shows that individual differences in paranormal and conspiracy beliefs are associated with perceptual and attentional biases, thereby extending the growing body of work in this field indicating effects of cultural learning on basic perceptual processes. PMID:26114604

What’s in a Face? How Face Gender and Current Affect Influence Perceived Emotion

PubMed Central

Harris, Daniel A.; Hayes-Skelton, Sarah A.; Ciaramitaro, Vivian M.

2016-01-01

Faces drive our social interactions. A vast literature suggests an interaction between gender and emotional face perception, with studies using different methodologies demonstrating that the gender of a face can affect how emotions are processed. However, how different is our perception of affective male and female faces? Furthermore, how does our current affective state when viewing faces influence our perceptual biases? We presented participants with a series of faces morphed along an emotional continuum from happy to angry. Participants judged each face morph as either happy or angry. We determined each participant’s unique emotional ‘neutral’ point, defined as the face morph judged to be perceived equally happy and angry, separately for male and female faces. We also assessed how current state affect influenced these perceptual neutral points. Our results indicate that, for both male and female participants, the emotional neutral point for male faces is perceptually biased to be happier than for female faces. This bias suggests that more happiness is required to perceive a male face as emotionally neutral, i.e., we are biased to perceive a male face as more negative. Interestingly, we also find that perceptual biases in perceiving female faces are correlated with current mood, such that positive state affect correlates with perceiving female faces as happier, while we find no significant correlation between negative state affect and the perception of facial emotion. Furthermore, we find reaction time biases, with slower responses for angry male faces compared to angry female faces. PMID:27733839

Divergent Perceptual Processes on Cyberbullying Between Victims and Aggressors: Construction of Explanatory Models.

PubMed

Fernández-Antelo, Inmaculada; Cuadrado-Gordillo, Isabel

2018-01-01

Understanding the causes of adolescents' aggressive behavior in and through technological means and resources requires a thorough analysis of the criteria that they consider to be identifying and defining cyberbullying and of the network of relationships established between the different criteria. The present study has aimed at making a foray into the attempt to understand the underlying structures and mechanisms that determine aggressors' and victims' perceptions of the cyberbullying phenomenon. The sample consisted of 2148 adolescents (49.1% girls; SD = 0.5) of ages from 12 to 16 ( M = 13.9; SD = 1.2). The data collected through a validated questionnaire for this study whose dimensions were confirmed from the data extracted from the focus groups and a CFA of the victim and aggressor subsamples. The analysis of the data is completed with CFA and the construction of structural models. The results have shown the importance and interdependence of imbalance of power and intention to harm in the aggressors' perceptual structure. The criteria of anonymity and repetition are related to the asymmetry of power, giving greater prominence to this factor. In its perceptual structure, the criterion "social relationship" also appears, which indicates that the manifestations of cyberbullying are sometimes interpreted as patterns of behavior that have become massively extended among the adolescent population, and have become accepted as a normalized and harmless way of communicating with other adolescents. In the victims' perceptual structure the key factor is the intention to harm, closely linked to the asymmetry of power and publicity. Anonymity, revenge and repetition are also present in this structure, although its relationship with cyberbullying is indirect. These results allow to design more effective measures of prevention and intervention closely tailored to addressing directly the factors that are considered to be predictors of risk.

Divergent Perceptual Processes on Cyberbullying Between Victims and Aggressors: Construction of Explanatory Models

PubMed Central

Fernández-Antelo, Inmaculada; Cuadrado-Gordillo, Isabel

2018-01-01

Understanding the causes of adolescents' aggressive behavior in and through technological means and resources requires a thorough analysis of the criteria that they consider to be identifying and defining cyberbullying and of the network of relationships established between the different criteria. The present study has aimed at making a foray into the attempt to understand the underlying structures and mechanisms that determine aggressors' and victims' perceptions of the cyberbullying phenomenon. The sample consisted of 2148 adolescents (49.1% girls; SD = 0.5) of ages from 12 to 16 (M = 13.9; SD = 1.2). The data collected through a validated questionnaire for this study whose dimensions were confirmed from the data extracted from the focus groups and a CFA of the victim and aggressor subsamples. The analysis of the data is completed with CFA and the construction of structural models. The results have shown the importance and interdependence of imbalance of power and intention to harm in the aggressors' perceptual structure. The criteria of anonymity and repetition are related to the asymmetry of power, giving greater prominence to this factor. In its perceptual structure, the criterion “social relationship” also appears, which indicates that the manifestations of cyberbullying are sometimes interpreted as patterns of behavior that have become massively extended among the adolescent population, and have become accepted as a normalized and harmless way of communicating with other adolescents. In the victims' perceptual structure the key factor is the intention to harm, closely linked to the asymmetry of power and publicity. Anonymity, revenge and repetition are also present in this structure, although its relationship with cyberbullying is indirect. These results allow to design more effective measures of prevention and intervention closely tailored to addressing directly the factors that are considered to be predictors of risk. PMID:29632506

Human visual perceptual organization beats thinking on speed.

PubMed

van der Helm, Peter A

2017-05-01

What is the degree to which knowledge influences visual perceptual processes? This question, which is central to the seeing-versus-thinking debate in cognitive science, is often discussed using examples claimed to be proof of one stance or another. It has, however, also been muddled by the usage of different and unclear definitions of perception. Here, for the well-defined process of perceptual organization, I argue that including speed (or efficiency) into the equation opens a new perspective on the limits of top-down influences of thinking on seeing. While the input of the perceptual organization process may be modifiable and its output enrichable, the process itself seems so fast (or efficient) that thinking hardly has time to intrude and is effective mostly after the fact.

Perceptual latency priming by masked and unmasked stimuli: evidence for an attentional interpretation.

PubMed

Scharlau, Ingrid; Neumann, Odmar

2003-08-01

Four experiments investigated the influence of a metacontrast-masked prime on temporal order judgments. The main results were (1) that a masked prime reduced the latency of the mask's conscious perception (perceptual latency priming), (2) that this effect was independent of whether the prime suffered strong or weak masking, (3) that it was unaffected by the degree of visual similarity between the prime and the mask, and that (4) there was no difference between congruent and incongruent primes. Finding (1) suggests that location cueing affects not only response times but also the latency of conscious perception. (2) The finding that priming was unaffected by the prime's detectability argues against a response bias interpretation of this effect. (3) Since visual similarity had no effect on the prime's efficiency, it is unlikely that sensory priming was involved. (4) The lack of a divergence between the effects of congruent and incongruent primes implies a functional difference between the judgments in the temporal order judgment task and speeded responses that have demonstrated differential effects of congruent and incongruent primes (e.g., Klotz & Neumann, 1999). These results can best be interpreted by assuming that the prime affects perceptual latency by initiating a shift of attention, as suggested by the Asynchronous Updating Model (AUM; Neumann 1978, 1982).

Role of perceptual and organizational factors in amnesics' recall of the Rey-Osterrieth complex figure: a comparison of three amnesic groups.

PubMed

Kixmiller, J S; Verfaellie, M M; Mather, M M; Cermak, L S

2000-04-01

To examine the contribution of visual-perceptual and visual-organizational factors to visual memory in amnesia, Korsakoff, medial temporal, and anterior communicating artery (ACoA) aneurysm amnesics' copy, organization, and recall performance on the Rey-Osterrieth Complex Figure was assessed. Korsakoff patients were matched to medial temporal patients in terms of severity of amnesia, while the ACoA group, which was less severely amnesic, was matched to the Korsakoff patients on performance on executive tasks. Results indicated that while both the ACoA and Korsakoff groups had poorer copy accuracy and organization than controls, only the Korsakoff patients' copy accuracy was worse than the other two amnesic groups. While the Korsakoff patient's visuoperceptual deficits could partially explain this group's poor performance at immediate recall, the Korsakoff group's comparatively worse performance at delayed recall could not be accounted for by poor copy accuracy, reduced visual organization, or even the combined influence of these two factors.

Age-related changes in selective attention and perceptual load during visual search.

PubMed

Madden, David J; Langley, Linda K

2003-03-01

Three visual search experiments were conducted to test the hypothesis that age differences in selective attention vary as a function of perceptual load (E. A. Maylor & N. Lavie, 1998). Under resource-limited conditions (Experiments 1 and 2), the distraction from irrelevant display items generally decreased as display size (perceptual load) increased. This perceptual load effect was similar for younger and older adults, contrary to the findings of Maylor and Lavie. Distraction at low perceptual loads appeared to reflect both general and specific inhibitory mechanisms. Under more data-limited conditions (Experiment 3), an age-related decline in selective attention was evident, but the age difference was not attributable to capacity limitations as predicted by the perceptual load theory.

First-Hand Accounts of Sensory Perceptual Experiences in Autism: A Qualitative Analysis.

ERIC Educational Resources Information Center

Jones, Robert S. P.; Quigney, Ciara; Huws, Jaci C.

2003-01-01

Five first-hand Web page accounts of unusual sensory perceptual experiences written by persons with high-functioning autism were selected for qualitative analysis. Four core categories emerged: turbulent sensory perceptual experiences; coping mechanisms; enjoyable sensory perceptual experiences; and awareness of being different, suggesting they…

Can we perceptually rate alaryngeal voice? Developing the Sunderland Tracheoesophageal Voice Perceptual Scale.

PubMed

Hurren, A; Hildreth, A J; Carding, P N

2009-12-01

To investigate the inter and intra reliability of raters (in relation to both profession and expertise) when judging two alaryngeal voice parameters: 'Overall Grade' and 'Neoglottal Tonicity'. Reliable perceptual assessment is essential for surgical and therapeutic outcome measurement but has been minimally researched to date. Test of inter and intra rater agreement from audio recordings of 55 tracheoesophageal speakers. Cancer Unit. Twelve speech and language therapists and ten Ear, Nose and Throat surgeons. Perceptual voice parameters of 'Overall Grade' rated with a 0-3 equally appearing interval scale and 'Neoglottal Tonicity' with an 11-point bipolar semantic scale. All raters achieved 'good' agreement for 'Overall Grade' with mean weighted kappa coefficients of 0.78 for intra and 0.70 for inter-rater agreement. All raters achieved 'good' intra-rater agreement for 'Neoglottal Tonicity' (0.64) but inter-rater agreement was only 'moderate' (0.40). However, the expert speech and language therapists sub-group attained 'good' inter-rater agreement with this parameter (0.63). The effect of 'Neoglottal Tonicity' on 'Overall Grade' was examined utilising only expert speech and language therapists data. Linear regression analysis resulted in an r-squared coefficient of 0.67. Analysis of the perceptual impression of hypotonicity and hypertonicity in relation to mean 'Overall Grade' score demonstrated neither tone was linked to a more favourable grade (P = 0.42). Expert speech and language therapist raters may be the optimal judges for tracheoesophageal voice assessment. Tonicity appears to be a good predictor of 'Overall Grade'. These scales have clinical applicability to investigate techniques that facilitate optotonic neoglottal voice quality.

Consensus paper: the role of the cerebellum in perceptual processes.

PubMed

Baumann, Oliver; Borra, Ronald J; Bower, James M; Cullen, Kathleen E; Habas, Christophe; Ivry, Richard B; Leggio, Maria; Mattingley, Jason B; Molinari, Marco; Moulton, Eric A; Paulin, Michael G; Pavlova, Marina A; Schmahmann, Jeremy D; Sokolov, Arseny A

2015-04-01

Various lines of evidence accumulated over the past 30 years indicate that the cerebellum, long recognized as essential for motor control, also has considerable influence on perceptual processes. In this paper, we bring together experts from psychology and neuroscience, with the aim of providing a succinct but comprehensive overview of key findings related to the involvement of the cerebellum in sensory perception. The contributions cover such topics as anatomical and functional connectivity, evolutionary and comparative perspectives, visual and auditory processing, biological motion perception, nociception, self-motion, timing, predictive processing, and perceptual sequencing. While no single explanation has yet emerged concerning the role of the cerebellum in perceptual processes, this consensus paper summarizes the impressive empirical evidence on this problem and highlights diversities as well as commonalities between existing hypotheses. In addition to work with healthy individuals and patients with cerebellar disorders, it is also apparent that several neurological conditions in which perceptual disturbances occur, including autism and schizophrenia, are associated with cerebellar pathology. A better understanding of the involvement of the cerebellum in perceptual processes will thus likely be important for identifying and treating perceptual deficits that may at present go unnoticed and untreated. This paper provides a useful framework for further debate and empirical investigations into the influence of the cerebellum on sensory perception.

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…

The multidimensional inventory of hypochondriacal traits: factor structure, specificity, reliability, and validity in patients with hypochondriasis.

PubMed

Witthöft, Michael; Weck, Florian; Gropalis, Maria

2015-06-01

Severe health anxiety constitutes a disabling and costly clinical condition. The Multidimensional Inventory of Hypochondriacal Traits (MIHT) represents an innovative instrument that was developed according to cognitive-behavioral, cognitive-perceptual, interpersonal, and trait models of hypochondriasis. We aimed at evaluating the psychometric properties of the MIHT in a sample of patients with the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) diagnosis of hypochondriasis. Using confirmatory factor analysis (CFA), the postulated four-factor structure of the MIHT was found in a first CFA in patients with hypochondriasis (n = 178) and in a second CFA based on a mixed sample, with other somatoform disorders (n = 27), panic disorder (n = 25), and healthy controls (n = 31) added to the original group of patients with hypochondriasis (n = 178). In terms of specificity, patients with hypochondriasis showed larger scores on all four MIHT subscales (i.e., affective, cognitive, behavioral, and perceptual) compared to all other groups. Analyses of convergent and discriminant validity revealed promising results concerning the MIHT affective and perceptual scales but also point to certain problematic issues concerning the MIHT cognitive and behavioral scales. The findings suggest that the proposed structure of the MIHT is valid also in patients with hypochondriasis and demonstrate the specificity of the four hypochondriacal traits assessed in the MIHT. © The Author(s) 2014.

Perceptual aspects of reproduced sound in car cabin acoustics.

PubMed

Kaplanis, Neofytos; Bech, Søren; Tervo, Sakari; Pätynen, Jukka; Lokki, Tapio; van Waterschoot, Toon; Jensen, Søren Holdt

2017-03-01

An experiment was conducted to determine the perceptual effects of car cabin acoustics on the reproduced sound field. In-car measurements were conducted whilst the cabin's interior was physically modified. The captured sound fields were recreated in the laboratory using a three-dimensional loudspeaker array. A panel of expert assessors followed a rapid sensory analysis protocol, the flash profile, to perceptually characterize and evaluate 12 acoustical conditions of the car cabin using individually elicited attributes. A multivariate analysis revealed the panel's consensus and the identified perceptual constructs. Six perceptual constructs characterize the differences between the acoustical conditions of the cabin, related to bass, ambience, transparency, width and envelopment, brightness, and image focus. The current results indicate the importance of several acoustical properties of a car's interior on the perceived sound qualities. Moreover, they signify the capacity of the applied methodology in assessing spectral and spatial properties of automotive environments in laboratory settings using a time-efficient and flexible protocol.

Neuroticism as Distancing: Perceptual Sources of Evidence

PubMed Central

Liu, Tianwei; Ode, Scott; Moeller, Sara K.; Robinson, Michael D.

2013-01-01

Several theories and self-reported sources of data link individual differences in negative affectivity to avoidance motivation. Chronic avoidance motivation, through repeated practice, may result in a relatively cognitive distance-enhancing dynamic whereby events and stimuli are perceived as further away from the self, even when they are not threatening. Such predictions are novel, but follow from cybernetic theories of self-regulation. In five studies (total N = 463), relations of this type were investigated. Study 1 presented participants with phrases that were ambiguous and found that trait negative affect predicted phrase interpretation in a distance-enhancing temporal direction. Study 2 replicated this effect across a systematic manipulation of event valence. Study 3 asked individuals to estimate the size of words and found that individuals higher in neuroticism generally perceived words to be smaller than did individuals lower in neuroticism. In Study 4, people high (but not low) in neuroticism perceived words to be shrinking faster than they were growing. In Study 5, greater perceptual distancing, in a font size estimation task, predicted more adverse reactions to negative events in daily life. Although normative effects varied across studies, consistent support for a chronic distancing perspective of individual differences in negative affectivity was found. PMID:23527850

Neuroticism as distancing: perceptual sources of evidence.

PubMed

Liu, Tianwei; Ode, Scott; Moeller, Sara K; Robinson, Michael D

2013-05-01

Several theories and self-reported sources of data link individual differences in negative affectivity to avoidance motivation. Chronic avoidance motivation, through repeated practice, may result in a relatively cognitive distance-enhancing dynamic whereby events and stimuli are perceived as further away from the self, even when they are not threatening. Such predictions are novel but follow from cybernetic theories of self-regulation. In 5 studies (total N = 463), relations of this type were investigated. Study 1 presented participants with phrases that were ambiguous and found that trait negative affect predicted phrase interpretation in a distance-enhancing temporal direction. Study 2 replicated this effect across a systematic manipulation of event valence. Study 3 asked individuals to estimate the size of words and found that individuals higher in neuroticism generally perceived words to be smaller than did individuals lower in neuroticism. In Study 4, people high (but not low) in neuroticism perceived words to be shrinking faster than they were growing. In Study 5, greater perceptual distancing, in a font size estimation task, predicted more adverse reactions to negative events in daily life. Although normative effects varied across studies, consistent support for a chronic distancing perspective of individual differences in negative affectivity was found. PsycINFO Database Record (c) 2013 APA, all rights reserved

The Role of Response Bias in Perceptual Learning

PubMed Central

2015-01-01

Sensory judgments improve with practice. Such perceptual learning is often thought to reflect an increase in perceptual sensitivity. However, it may also represent a decrease in response bias, with unpracticed observers acting in part on a priori hunches rather than sensory evidence. To examine whether this is the case, 55 observers practiced making a basic auditory judgment (yes/no amplitude-modulation detection or forced-choice frequency/amplitude discrimination) over multiple days. With all tasks, bias was present initially, but decreased with practice. Notably, this was the case even on supposedly “bias-free,” 2-alternative forced-choice, tasks. In those tasks, observers did not favor the same response throughout (stationary bias), but did favor whichever response had been correct on previous trials (nonstationary bias). Means of correcting for bias are described. When applied, these showed that at least 13% of perceptual learning on a forced-choice task was due to reduction in bias. In other situations, changes in bias were shown to obscure the true extent of learning, with changes in estimated sensitivity increasing once bias was corrected for. The possible causes of bias and the implications for our understanding of perceptual learning are discussed. PMID:25867609

A Bayesian Attractor Model for Perceptual Decision Making

PubMed Central

Bitzer, Sebastian; Bruineberg, Jelle; Kiebel, Stefan J.

2015-01-01

Even for simple perceptual decisions, the mechanisms that the brain employs are still under debate. Although current consensus states that the brain accumulates evidence extracted from noisy sensory information, open questions remain about how this simple model relates to other perceptual phenomena such as flexibility in decisions, decision-dependent modulation of sensory gain, or confidence about a decision. We propose a novel approach of how perceptual decisions are made by combining two influential formalisms into a new model. Specifically, we embed an attractor model of decision making into a probabilistic framework that models decision making as Bayesian inference. We show that the new model can explain decision making behaviour by fitting it to experimental data. In addition, the new model combines for the first time three important features: First, the model can update decisions in response to switches in the underlying stimulus. Second, the probabilistic formulation accounts for top-down effects that may explain recent experimental findings of decision-related gain modulation of sensory neurons. Finally, the model computes an explicit measure of confidence which we relate to recent experimental evidence for confidence computations in perceptual decision tasks. PMID:26267143

Perceptual processing during trauma, priming and the development of intrusive memories

PubMed Central

Sündermann, Oliver; Hauschildt, Marit; Ehlers, Anke

2013-01-01

Background Intrusive reexperiencing in posttraumatic stress disorder (PTSD) is commonly triggered by stimuli with perceptual similarity to those present during the trauma. Information processing theories suggest that perceptual processing during the trauma and enhanced perceptual priming contribute to the easy triggering of intrusive memories by these cues. Methods Healthy volunteers (N = 51) watched neutral and trauma picture stories on a computer screen. Neutral objects that were unrelated to the content of the stories briefly appeared in the interval between the pictures. Dissociation and data-driven processing (as indicators of perceptual processing) and state anxiety during the stories were assessed with self-report questionnaires. After filler tasks, participants completed a blurred object identification task to assess priming and a recognition memory task. Intrusive memories were assessed with telephone interviews 2 weeks and 3 months later. Results Neutral objects were more strongly primed if they occurred in the context of trauma stories than if they occurred during neutral stories, although the effect size was only moderate (ηp2=.08) and only significant when trauma stories were presented first. Regardless of story order, enhanced perceptual priming predicted intrusive memories at 2-week follow-up (N = 51), but not at 3 months (n = 40). Data-driven processing, dissociation and anxiety increases during the trauma stories also predicted intrusive memories. Enhanced perceptual priming and data-driven processing were associated with lower verbal intelligence. Limitations It is unclear to what extent these findings generalize to real-life traumatic events and whether they are specific to negative emotional events. Conclusions The results provide some support for the role of perceptual processing and perceptual priming in reexperiencing symptoms. PMID:23207970

The Spatial Focus of Attention Is Controlled at Perceptual and Cognitive Levels

ERIC Educational Resources Information Center

Caparos, Serge; Linnell, Karina J.

2010-01-01

Selective attention has been hypothesized to reduce distractor interference at both perceptual and postperceptual levels (Lavie, 2005), respectively, by focusing perceptual resources on the attended location and by blocking at postperceptual levels distractors that survive perceptual selection. This study measured the impact of load on these…

Perceptual Repetition Blindness Effects

NASA Technical Reports Server (NTRS)

Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

1994-01-01

The phenomenon of repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to post-perceptual processes such as memory retrieval and/or reporting biases. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is, indeed, open to such objections. Here we investigate RB using a "single-frame" paradigm introduced by Johnston and Hale (1984) in which memory demands are minimal. Subjects made only a single judgement about whether one masked target word was the same or different than a post-target probe. Confidence ratings permitted use of signal detection methods to assess sensitivity and bias effects. In the critical condition for RB a precue of the post-target word was provided prior to the target stimulus (identity precue), so that the required judgement amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was either an unrelated word or a dummy.

Perceptual Learning and Attention: Reduction of Object Attention Limitations with Practice

PubMed Central

Dosher, Barbara Anne; Han, Songmei; Lu, Zhong-Lin

2012-01-01

Perceptual learning has widely been claimed to be attention driven; attention assists in choosing the relevant sensory information and attention may be necessary in many cases for learning. In this paper, we focus on the interaction of perceptual learning and attention – that perceptual learning can reduce or eliminate the limitations of attention, or, correspondingly, that perceptual learning depends on the attention condition. Object attention is a robust limit on performance. Two attributes of a single attended object may be reported without loss, while the same two attributes of different objects can exhibit a substantial dual-report deficit due to the sharing of attention between objects. The current experiments document that this fundamental dual-object report deficit can be reduced, or eliminated, through perceptual learning that is partially specific to retinal location. This suggests that alternative routes established by practice may reduce the competition between objects for processing resources. PMID:19796653

Perceptual Specificity Effects in Rereading: Evidence from Eye Movements

ERIC Educational Resources Information Center

Sheridan, Heather; Reingold, Eyal M.

2012-01-01

The present experiments examined perceptual specificity effects using a rereading paradigm. Eye movements were monitored while participants read the same target word twice, in two different low-constraint sentence frames. The congruency of perceptual processing was manipulated by either presenting the target word in the same distortion typography…

Active and Passive Perceptual Learning in the Visually Impaired.

ERIC Educational Resources Information Center

Conrod, Beverley E.; And Others

1986-01-01

Active and passive perceptual training methods were tested with 30 macular degeneration patients to improve their residual vision. The main conclusion was that perceptual training may contribute to successful visual adjustment and that the effect of training is not limited to a particular level of visual impairment. (Author/CL)

Perceptual and cognitive effects of antipsychotics in first-episode schizophrenia: the potential impact of GABA concentration in the visual cortex.

PubMed

Kelemen, Oguz; Kiss, Imre; Benedek, György; Kéri, Szabolcs

2013-12-02

Schizophrenia is characterized by anomalous perceptual experiences (e.g., sensory irritation, inundation, and flooding) and specific alterations in visual perception. We aimed to investigate the effects of short-term antipsychotic medication on these perceptual alterations. We assessed 28 drug-naïve first episode patients with schizophrenia and 20 matched healthy controls at baseline and follow-up 8 weeks later. Contrast sensitivity was measured with steady- and pulsed-pedestal tests. Participants also received a motion coherence task, the Structured Interview for Assessing Perceptual Anomalies (SIAPA), and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Proton magnetic resonance spectroscopy was used to measure gamma-aminobutyric acid (GABA) levels in the occipital cortex (GABA/total creatine [Cr] ratio). Results revealed that, comparing baseline and follow-up values, patients with schizophrenia exhibited a marked sensitivity reduction on the steady-pedestal test at low spatial frequency. Anomalous perceptual experiences were also significantly ameliorated. Antipsychotic medications had no effect on motion perception. RBANS scores showed mild improvements. At baseline, but not at follow-up, patients with schizophrenia outperformed controls on the steady-pedestal test at low spatial frequency. The dysfunction of motion perception (higher coherence threshold in patients relative to controls) was similar at both assessments. There were reduced GABA levels in schizophrenia at both assessments, which were not related to perceptual functions. These results suggest that antipsychotics dominantly affect visual contrast sensitivity and anomalous perceptual experiences. The prominent dampening effect on low spatial frequency in the steady-pedestal test might indicate the normalization of putatively overactive magnocellular retino-geniculo-cortical pathways. © 2013.

Perceptual learning of degraded speech by minimizing prediction error.

PubMed

Sohoglu, Ediz; Davis, Matthew H

2016-03-22

Human perception is shaped by past experience on multiple timescales. Sudden and dramatic changes in perception occur when prior knowledge or expectations match stimulus content. These immediate effects contrast with the longer-term, more gradual improvements that are characteristic of perceptual learning. Despite extensive investigation of these two experience-dependent phenomena, there is considerable debate about whether they result from common or dissociable neural mechanisms. Here we test single- and dual-mechanism accounts of experience-dependent changes in perception using concurrent magnetoencephalographic and EEG recordings of neural responses evoked by degraded speech. When speech clarity was enhanced by prior knowledge obtained from matching text, we observed reduced neural activity in a peri-auditory region of the superior temporal gyrus (STG). Critically, longer-term improvements in the accuracy of speech recognition following perceptual learning resulted in reduced activity in a nearly identical STG region. Moreover, short-term neural changes caused by prior knowledge and longer-term neural changes arising from perceptual learning were correlated across subjects with the magnitude of learning-induced changes in recognition accuracy. These experience-dependent effects on neural processing could be dissociated from the neural effect of hearing physically clearer speech, which similarly enhanced perception but increased rather than decreased STG responses. Hence, the observed neural effects of prior knowledge and perceptual learning cannot be attributed to epiphenomenal changes in listening effort that accompany enhanced perception. Instead, our results support a predictive coding account of speech perception; computational simulations show how a single mechanism, minimization of prediction error, can drive immediate perceptual effects of prior knowledge and longer-term perceptual learning of degraded speech.

Perceptual learning of degraded speech by minimizing prediction error

PubMed Central

Sohoglu, Ediz

2016-01-01

Human perception is shaped by past experience on multiple timescales. Sudden and dramatic changes in perception occur when prior knowledge or expectations match stimulus content. These immediate effects contrast with the longer-term, more gradual improvements that are characteristic of perceptual learning. Despite extensive investigation of these two experience-dependent phenomena, there is considerable debate about whether they result from common or dissociable neural mechanisms. Here we test single- and dual-mechanism accounts of experience-dependent changes in perception using concurrent magnetoencephalographic and EEG recordings of neural responses evoked by degraded speech. When speech clarity was enhanced by prior knowledge obtained from matching text, we observed reduced neural activity in a peri-auditory region of the superior temporal gyrus (STG). Critically, longer-term improvements in the accuracy of speech recognition following perceptual learning resulted in reduced activity in a nearly identical STG region. Moreover, short-term neural changes caused by prior knowledge and longer-term neural changes arising from perceptual learning were correlated across subjects with the magnitude of learning-induced changes in recognition accuracy. These experience-dependent effects on neural processing could be dissociated from the neural effect of hearing physically clearer speech, which similarly enhanced perception but increased rather than decreased STG responses. Hence, the observed neural effects of prior knowledge and perceptual learning cannot be attributed to epiphenomenal changes in listening effort that accompany enhanced perception. Instead, our results support a predictive coding account of speech perception; computational simulations show how a single mechanism, minimization of prediction error, can drive immediate perceptual effects of prior knowledge and longer-term perceptual learning of degraded speech. PMID:26957596

Angular relation of axes in perceptual space

NASA Technical Reports Server (NTRS)

Bucher, Urs

1992-01-01

The geometry of perceptual space needs to be known to model spatial orientation constancy or to create virtual environments. To examine one main aspect of this geometry, the angular relation between the three spatial axes was measured. Experiments were performed consisting of a perceptual task in which subjects were asked to set independently their apparent vertical and horizontal plane. The visual background provided no other stimuli to serve as optical direction cues. The task was performed in a number of different body tilt positions with pitches and rolls varied in steps of 30 degs. The results clearly show the distortion of orthogonality of the perceptual space for nonupright body positions. Large interindividual differences were found. Deviations from orthogonality up to 25 deg were detected in the pitch as well as in the roll direction. Implications of this nonorthogonality on further studies of spatial perception and on the construction of virtual environments for human interaction is also discussed.

Revisiting a Cognitive Framework for Test Design: Applications for a Computerized Perceptual Speed Test.

ERIC Educational Resources Information Center

Alderton, David L.

This paper highlights the need for a systematic, content aware, and theoretically-based approach to test design. The cognitive components approach is endorsed, and is applied to the development of a computerized perceptual speed test. Psychometric literature is reviewed and shows that: every major multi-factor theory includes a clerical/perceptual…

Colorful Success: Preschoolers' Use of Perceptual Color Cues to Solve a Spatial Reasoning Problem

ERIC Educational Resources Information Center

Joh, Amy S.; Spivey, Leigh A.

2012-01-01

Spatial reasoning, a crucial skill for everyday actions, develops gradually during the first several years of childhood. Previous studies have shown that perceptual information and problem solving strategies are critical for successful spatial reasoning in young children. Here, we sought to link these two factors by examining children's use of…

Video gaming enhances psychomotor skills but not visuospatial and perceptual abilities in surgical trainees.

PubMed

Kennedy, A M; Boyle, E M; Traynor, O; Walsh, T; Hill, A D K

2011-01-01

There is considerable interest in the identification and assessment of underlying aptitudes or innate abilities that could potentially predict excellence in the technical aspects of operating. However, before the assessment of innate abilities is introduced for high-stakes assessment (such as competitive selection into surgical training programs), it is essential to determine that these abilities are stable and unchanging and are not influenced by other factors, such as the use of video games. The aim of this study was to investigate whether experience playing video games will predict psychomotor performance on a laparoscopic simulator or scores on tests of visuospatial and perceptual abilities, and to examine the correlation, if any, between these innate abilities. Institutional ethical approval was obtained. Thirty-eight undergraduate medical students with no previous surgical experience were recruited. All participants completed a self-reported questionnaire that asked them to detail their video game experience. They then underwent assessment of their psychomotor, visuospatial, and perceptual abilities using previously validated tests. The results were analyzed using independent samples t tests to compare means and linear regression curves for subsequent analysis. Students who played video games for at least 7 hours per week demonstrated significantly better psychomotor skills than students who did not play video games regularly. However, there was no difference on measures of visuospatial and perceptual abilities. There was no correlation between psychomotor tests and visuospatial or perceptual tests. Regular video gaming correlates positively with psychomotor ability, but it does not seem to influence visuospatial or perceptual ability. This study suggests that video game experience might be beneficial to a future career in surgery. It also suggests that relevant surgical skills may be gained usefully outside the operating room in activities that are not

Mid-level perceptual features distinguish objects of different real-world sizes.

PubMed

Long, Bria; Konkle, Talia; Cohen, Michael A; Alvarez, George A

2016-01-01

Understanding how perceptual and conceptual representations are connected is a fundamental goal of cognitive science. Here, we focus on a broad conceptual distinction that constrains how we interact with objects--real-world size. Although there appear to be clear perceptual correlates for basic-level categories (apples look like other apples, oranges look like other oranges), the perceptual correlates of broader categorical distinctions are largely unexplored, i.e., do small objects look like other small objects? Because there are many kinds of small objects (e.g., cups, keys), there may be no reliable perceptual features that distinguish them from big objects (e.g., cars, tables). Contrary to this intuition, we demonstrated that big and small objects have reliable perceptual differences that can be extracted by early stages of visual processing. In a series of visual search studies, participants found target objects faster when the distractor objects differed in real-world size. These results held when we broadly sampled big and small objects, when we controlled for low-level features and image statistics, and when we reduced objects to texforms--unrecognizable textures that loosely preserve an object's form. However, this effect was absent when we used more basic textures. These results demonstrate that big and small objects have reliably different mid-level perceptual features, and suggest that early perceptual information about broad-category membership may influence downstream object perception, recognition, and categorization processes. (c) 2015 APA, all rights reserved).

Perceptual Learning: 12-Month-Olds' Discrimination of Monkey Faces

ERIC Educational Resources Information Center

Fair, Joseph; Flom, Ross; Jones, Jacob; Martin, Justin

2012-01-01

Six-month-olds reliably discriminate different monkey and human faces whereas 9-month-olds only discriminate different human faces. It is often falsely assumed that perceptual narrowing reflects a permanent change in perceptual abilities. In 3 experiments, ninety-six 12-month-olds' discrimination of unfamiliar monkey faces was examined. Following…

Dimension-Based Statistical Learning Affects Both Speech Perception and Production.

PubMed

Lehet, Matthew; Holt, Lori L

2017-04-01

Multiple acoustic dimensions signal speech categories. However, dimensions vary in their informativeness; some are more diagnostic of category membership than others. Speech categorization reflects these dimensional regularities such that diagnostic dimensions carry more "perceptual weight" and more effectively signal category membership to native listeners. Yet perceptual weights are malleable. When short-term experience deviates from long-term language norms, such as in a foreign accent, the perceptual weight of acoustic dimensions in signaling speech category membership rapidly adjusts. The present study investigated whether rapid adjustments in listeners' perceptual weights in response to speech that deviates from the norms also affects listeners' own speech productions. In a word recognition task, the correlation between two acoustic dimensions signaling consonant categories, fundamental frequency (F0) and voice onset time (VOT), matched the correlation typical of English, and then shifted to an "artificial accent" that reversed the relationship, and then shifted back. Brief, incidental exposure to the artificial accent caused participants to down-weight perceptual reliance on F0, consistent with previous research. Throughout the task, participants were intermittently prompted with pictures to produce these same words. In the block in which listeners heard the artificial accent with a reversed F0 × VOT correlation, F0 was a less robust cue to voicing in listeners' own speech productions. The statistical regularities of short-term speech input affect both speech perception and production, as evidenced via shifts in how acoustic dimensions are weighted. Copyright © 2016 Cognitive Science Society, Inc.

JPEG2000 encoding with perceptual distortion control.

PubMed

Liu, Zhen; Karam, Lina J; Watson, Andrew B

2006-07-01

In this paper, a new encoding approach is proposed to control the JPEG2000 encoding in order to reach a desired perceptual quality. The new method is based on a vision model that incorporates various masking effects of human visual perception and a perceptual distortion metric that takes spatial and spectral summation of individual quantization errors into account. Compared with the conventional rate-based distortion minimization JPEG2000 encoding, the new method provides a way to generate consistent quality images at a lower bit rate.

Effects of perceptual load and socially meaningful stimuli on crossmodal selective attention in Autism Spectrum Disorder and neurotypical samples.

PubMed

Tyndall, Ian; Ragless, Liam; O'Hora, Denis

2018-04-01

The present study examined whether increasing visual perceptual load differentially affected both Socially Meaningful and Non-socially Meaningful auditory stimulus awareness in neurotypical (NT, n = 59) adults and Autism Spectrum Disorder (ASD, n = 57) adults. On a target trial, an unexpected critical auditory stimulus (CAS), either a Non-socially Meaningful ('beep' sound) or Socially Meaningful ('hi') stimulus, was played concurrently with the presentation of the visual task. Under conditions of low visual perceptual load both NT and ASD samples reliably noticed the CAS at similar rates (77-81%), whether the CAS was Socially Meaningful or Non-socially Meaningful. However, during high visual perceptual load NT and ASD participants reliably noticed the meaningful CAS (NT = 71%, ASD = 67%), but NT participants were unlikely to notice the Non-meaningful CAS (20%), whereas ASD participants reliably noticed it (80%), suggesting an inability to engage selective attention to ignore non-salient irrelevant distractor stimuli in ASD. Copyright © 2018 Elsevier Inc. All rights reserved.

Economic and Cultural Factors Affecting University Excellence

ERIC Educational Resources Information Center

Jabnoun, Naceur

2009-01-01

Purpose: The ranking of top universities in the world has generated increased interest in the factors that enhance university performance. The purpose of this paper is to identify economic and cultural factors that affect the number of top ranking universities in each country. Design/methodology/approach: This paper first identifies the number of…

Perceptual aspects of singing.

PubMed

Sundberg, J

1994-06-01

The relations between acoustic and perceived characteristics of vowel sounds are demonstrated with respect to timbre, loudness, pitch, and expressive time patterns. The conditions for perceiving an ensemble of sine tones as one tone or several tones are reviewed. There are two aspects of timbre of voice sounds: vowel quality and voice quality. Although vowel quality depends mainly on the frequencies of the lowest two formants. In particular, the center frequency of the so-called singer's formant seems perceptually relevant. Vocal loudness, generally assumed to correspond closely to the sound pressure level, depends rather on the amplitude balance between the lower and the higher spectrum partials. The perceived pitch corresponds to the fundamental frequency, or for vibrato tones, the mean of this frequency. In rapid passages, such as coloratura singing, special patterns are used. Pitch and duration differences are categorically perceived in music. This means that small variations in tuning or duration do not affect the musical interval and the note value perceived. Categorical perception is used extensively in music performance for the purpose of musical expression because without violating the score, the singer may sharpen or flatten and lengthen or shorten the tones, thereby creating musical expression.

Perceptual-motor skill learning in Gilles de la Tourette syndrome. Evidence for multiple procedural learning and memory systems.

PubMed

Marsh, Rachel; Alexander, Gerianne M; Packard, Mark G; Zhu, Hongtu; Peterson, Bradley S

2005-01-01

Procedural learning and memory systems likely comprise several skills that are differentially affected by various illnesses of the central nervous system, suggesting their relative functional independence and reliance on differing neural circuits. Gilles de la Tourette syndrome (GTS) is a movement disorder that involves disturbances in the structure and function of the striatum and related circuitry. Recent studies suggest that patients with GTS are impaired in performance of a probabilistic classification task that putatively involves the acquisition of stimulus-response (S-R)-based habits. Assessing the learning of perceptual-motor skills and probabilistic classification in the same samples of GTS and healthy control subjects may help to determine whether these various forms of procedural (habit) learning rely on the same or differing neuroanatomical substrates and whether those substrates are differentially affected in persons with GTS. Therefore, we assessed perceptual-motor skill learning using the pursuit-rotor and mirror tracing tasks in 50 patients with GTS and 55 control subjects who had previously been compared at learning a task of probabilistic classifications. The GTS subjects did not differ from the control subjects in performance of either the pursuit rotor or mirror-tracing tasks, although they were significantly impaired in the acquisition of a probabilistic classification task. In addition, learning on the perceptual-motor tasks was not correlated with habit learning on the classification task in either the GTS or healthy control subjects. These findings suggest that the differing forms of procedural learning are dissociable both functionally and neuroanatomically. The specific deficits in the probabilistic classification form of habit learning in persons with GTS are likely to be a consequence of disturbances in specific corticostriatal circuits, but not the same circuits that subserve the perceptual-motor form of habit learning.

Perceptual awareness and its neural basis: bridging experimental and theoretical paradigms

PubMed Central

Raffone, Antonino; Srinivasan, Narayanan; van Leeuwen, Cees

2014-01-01

Understanding consciousness is a major scientific challenge of our times, and perceptual awareness is an integral part of that challenge. This Theme Issue aims to provide a timely focus on crucial insights from leading scientists on perceptual awareness and its neural basis. The issue refers to key research questions and findings in perceptual awareness research and aims to be a catalyst for further research, by bringing together the state-of-the-art. It shows how bridges are being built between empirical and theoretical research and proposes new directions for the study of multisensory awareness and the role of the states of the body therein. In this introduction, we highlight crucial problems that have characterized the development of the study of perceptual awareness. We then provide an overview of major experimental and theoretical paradigms related to perceptual awareness and its neural basis. Finally, we present an overview of the Theme Issue, with reference to the contributed articles and their relationships. PMID:24639576

Two mechanisms of constructive recollection: Perceptual recombination and conceptual fluency.

PubMed

Doss, Manoj K; Bluestone, Maximilian R; Gallo, David A

2016-11-01

Recollection is constructive and prone to distortion, but the mechanisms through which recollections can become embellished with rich yet illusory details are still debated. According to the conceptual fluency hypothesis, abstract semantic or conceptual activation increases the familiarity of a nonstudied event, causing one to falsely attribute imagined features to actual perception. In contrast, according to the perceptual recombination hypothesis, details from actually perceived events are partially recollected and become erroneously bound to a nonstudied event, again causing a detailed yet false recollection. Here, we report the first experiments aimed at disentangling these 2 mechanisms. Participants imagined pictures of common objects, and then they saw an actual picture of some of the imagined objects. We next presented misinformation associated with these studied items, designed to increase conceptual fluency (i.e., semantically related words) or perceptual recombination (i.e., perceptually similar picture fragments). Finally, we tested recollection for the originally seen pictures using verbal labels as retrieval cues. Consistent with conceptual fluency, processing-related words increased false recollection of pictures that were never seen, and consistent with perceptual recombination, processing picture fragments further increased false recollection. We also found that conceptual fluency was more short-lived than perceptual recombination, further dissociating these 2 mechanisms. These experiments provide strong evidence that conceptual fluency and perceptual recombination independently contribute to the constructive aspects of recollection. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Perceptual and Cognitive Load Interact to Control the Spatial Focus of Attention

ERIC Educational Resources Information Center

Linnell, Karina J.; Caparos, Serge

2011-01-01

Caparos and Linnell (2009, 2010) used a variable-separation flanker paradigm to show that (a) when cognitive load is low, increasing perceptual load causes spatial attention to focus and (b) when perceptual load is high, decreasing cognitive load causes spatial attention to focus. Here, we tested whether the effects of perceptual and cognitive…

Human Perceptual Performance With Nonliteral Imagery: Region Recognition and Texture-Based Segmentation

ERIC Educational Resources Information Center

Essock, Edward A.; Sinai, Michael J.; DeFord, Kevin; Hansen, Bruce C.; Srinivasan, Narayanan

2004-01-01

In this study the authors address the issue of how the perceptual usefulness of nonliteral imagery should be evaluated. Perceptual performance with nonliteral imagery of natural scenes obtained at night from infrared and image-intensified sensors and from multisensor fusion methods was assessed to relate performance on 2 basic perceptual tasks to…

ENVIRONMENTAL FACTORS AFFECTING BREAST CANCER SUSCEPTIBILITY

EPA Science Inventory

Environmental Factors Affecting Breast Cancer Susceptibility
Suzanne. E. Fenton
US EPA, ORD, MD-67 NHEERL, Reproductive Toxicology Division, Research Triangle Park, NC 27711.

Breast cancer is still the most common malignancy afflicting women in the Western world. Alt...

Harnessing the Wandering Mind: The Role of Perceptual Load

ERIC Educational Resources Information Center

Forster, Sophie; Lavie, Nilli

2009-01-01

Perceptual load is a key determinant of distraction by task-irrelevant stimuli (e.g., Lavie, N. (2005). "Distracted and confused?: Selective attention under load." "Trends in Cognitive Sciences," 9, 75-82). Here we establish the role of perceptual load in determining an internal form of distraction by task-unrelated thoughts (TUTs or…

Multisensory Cues Capture Spatial Attention Regardless of Perceptual Load

ERIC Educational Resources Information Center

Santangelo, Valerio; Spence, Charles

2007-01-01

We compared the ability of auditory, visual, and audiovisual (bimodal) exogenous cues to capture visuo-spatial attention under conditions of no load versus high perceptual load. Participants had to discriminate the elevation (up vs. down) of visual targets preceded by either unimodal or bimodal cues under conditions of high perceptual load (in…

Estimating the Growth of Internal Evidence Guiding Perceptual Decisions

ERIC Educational Resources Information Center

Ludwig, Casimir J. H.; Davies, J. Rhys

2011-01-01

Perceptual decision-making is thought to involve a gradual accrual of noisy evidence. Temporal integration of the evidence reduces the relative contribution of dynamic internal noise to the decision variable, thereby boosting its signal-to-noise ratio. We aimed to estimate the internal evidence guiding perceptual decisions over time, using a novel…

Bayesian Face Recognition and Perceptual Narrowing in Face-Space

ERIC Educational Resources Information Center