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1

Age-related slowing of memory retrieval: Contributions of perceptual speed and cerebral white matter integrity  

PubMed Central

Previous research suggests that, in reaction time (RT) measures of episodic memory retrieval, the unique effects of adult age are relatively small compared to the effects aging shares with more elementary abilities such as perceptual speed. Little is known, however, regarding the mechanisms of perceptual speed. We used diffusion tensor imaging (DTI) to test the hypothesis that white matter integrity, as indexed by fractional anisotropy (FA), serves as one mechanism of perceptual slowing in episodic memory retrieval. Results indicated that declines in FA in the pericallosal frontal region and in the genu of the corpus callosum, but not in other regions, mediated the relationship between perceptual speed and episodic retrieval RT. This relation held, though to a different degree, for both hits and correct rejections. These findings suggest that white matter integrity in prefrontal regions is one mechanism underlying the relation between individual differences in perceptual speed and episodic retrieval. PMID:17383774

Bucur, Barbara; Madden, David J.; Spaniol, Julia; Provenzale, James M.; Cabeza, Roberto; White, Leonard E.; Huettel, Scott A.

2007-01-01

2

Perceptual Simulations and Linguistic Representations Have Differential Effects on Speeded Relatedness Judgments and Recognition Memory  

PubMed Central

We examined the effect of spatial iconicity (a perceptual simulation of canonical locations of objects) and word-order frequency on language processing and episodic memory of orientation. Participants made speeded relatedness judgments to pairs of words presented in locations typical to their real world arrangements (e.g., ceiling on top and floor on bottom). They then engaged in a surprise orientation recognition task for the word pairs. We replicated Louwerse’s finding (2008) that word-order frequency has a stronger effect on semantic relatedness judgments than spatial iconicity. This is consistent with recent suggestions that linguistic representations have a stronger impact on immediate decisions about verbal materials than perceptual simulations. In contrast, spatial iconicity enhanced episodic memory of orientation to a greater extent than word-order frequency did. This new finding indicates that perceptual simulations have an important role in episodic memory. Results are discussed with respect to theories of perceptual representation and linguistic processing. PMID:19742388

Tse, Chi-Shing; Kurby, Christopher A.; Du, Feng

2010-01-01

3

WAIS-III processing speed index scores after TBI: the influence of working memory, psychomotor speed and perceptual processing.  

PubMed

This study investigates the extent to which working memory, motor speed and perceptual processing speed influence Wechsler Adult Intelligence Scale-III (WAIS-III) Processing Speed Index (PSI) scores. Sixty-eight adult outpatients with Traumatic Brain Injury (TBI) of varying severity and complete data on all outcome measures were identified. Two cases with outlying values on one outcome measure were omitted from the final sample. Working memory was measured by the Working Memory Index score from the WAIS-III. Motor speed was measured as score on the Halstead-Reitan Finger Oscillation Test (finger tapping) and perceptual processing as score on the Trail Making Test--Part B. In hierarchical multiple regression analyses, working memory accounted for 10% of the variance in PSI scores, whereas motor speed only accounted for 3%. An independent measure of perceptual processing, Trail Making Test--B, accounted for 26% of the variance in WAIS-III PSI scores. The total variance accounted for by the three factors was 56%. Findings confirm that the WAIS-III PSI scores of individuals who have received a TBI reflect perceptual processing speed, with an additional component attributable to working memory. Motor speed made only a small contribution to WAIS-III PSI scores in the present sample. PMID:14704894

Kennedy, Jan E; Clement, Pamelia F; Curtiss, Glenn

2003-08-01

4

On the relationship between autobiographical memory and perceptual learning  

Microsoft Academic Search

Reports experiments designed to explore the relationship between the more aware autobiographical form of memory that is measured by a recognition memory test and the less aware form of memory that is expressed in perceptual learning. Ss were 247 undergraduates. Variables such as the level of processing of words during study influenced recognition memory, but not subsequent perceptual recognition. In

Larry L. Jacoby; Mark Dallas

1981-01-01

5

Depressive Symptoms Predict Decline in Perceptual Speed in Older Adulthood  

PubMed Central

Depressive symptoms and cognitive decline are associated in older age, but research is inconsistent about whether one condition influences the development of the other. We examined the directionality of relations between depressive symptoms and perceptual speed using bivariate dual change score models. Assessments of depressive symptoms and perceptual speed were completed by 1,206 nondemented older adults at baseline, and after two, eight, eleven, and fifteen years. After controlling for age, education, baseline general cognitive ability, and self-reported health, allowing depressive symptoms to predict subsequent change in perceptual speed provided the best fit. More depressive symptoms predicted subsequently stronger declines in perceptual speed over time lags of one year. PMID:21517186

Bielak, Allison A. M.; Gerstorf, Denis; Kiely, Kim M.; Anstey, Kaarin J.; Luszcz, Mary

2012-01-01

6

Memory: Enduring Traces of Perceptual and Reflective Attention  

PubMed Central

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

Chun, Marvin M.; Johnson, Marcia K.

2011-01-01

7

Great Expectations: Temporal Expectation Modulates Perceptual Processing Speed  

ERIC Educational Resources Information Center

In a crowded dynamic world, temporal expectations guide our attention in time. Prior investigations have consistently demonstrated that temporal expectations speed motor behavior. We explore effects of temporal expectation on "perceptual" speed in three nonspeeded, cued recognition paradigms. Different hazard rate functions for the cue-stimulus…

Vangkilde, Signe; Coull, Jennifer T.; Bundesen, Claus

2012-01-01

8

Perceptual memory drives learning of retinotopic biases for bistable stimuli  

PubMed Central

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. PMID:24550874

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

2014-01-01

9

Perceptual memory drives learning of retinotopic biases for bistable stimuli.  

PubMed

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. PMID:24550874

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

2014-01-01

10

Who Can You Trust? Behavioral and Neural Differences Between Perceptual and Memory-Based Influences  

PubMed Central

Decisions about whether to trust someone can be influenced by competing sources of information, such as analysis of facial features versus remembering specific information about the person. We hypothesized that such sources can differentially influence trustworthiness judgments depending on the circumstances in which judgments are made. In our experiments, subjects first learned face-word associations. Stimuli were trustworthy and untrustworthy faces, selected on the basis of consensus judgments, and personality attributes that carried either the same valence (consistent with face) or the opposite valence (inconsistent with face). Subsequently, subjects rated the trustworthiness of each face. Both learned and perceptual information influenced ratings, but learned information was less influential under speeded than under non-speeded conditions. EEG data further revealed neural evidence of the processing of these two competing sources. Perceptual influences were apparent earlier than memory influences, substantiating the conclusion that time pressure can selectively disrupt memory retrieval relevant to trustworthiness attributions. PMID:19738922

Rudoy, John D.; Paller, Ken A.

2009-01-01

11

Differential Effects of Intelligence, Perceptual Speed and Age on Growth in Attentional Speed and Accuracy  

ERIC Educational Resources Information Center

The study investigates the effects of intelligence, perceptual speed and age on intraindividual growth in attentional speed and attentional accuracy over the course of a 6-minute testing session. A sample of 193 subjects completed the Advanced Progressive Matrices and the Vienna Matrices Test representing intelligence, the tests Alertness and…

Goldhammer, Frank; Rauch, Wolfgang A.; Schweizer, Karl; Moosbrugger, Helfried

2010-01-01

12

Us and them: Memory advantages in perceptually ambiguous groups  

Microsoft Academic Search

Ingroup advantages and outgroup deficits in perception and memory are well-established in research on race, gender, and other\\u000a ostensibly identifiable social categories. The present study extended this research to a social category that is not as perceptually\\u000a apparent: male sexual orientation. Consistent with hypotheses, an interaction of participant sexual orientation and image\\u000a sexual orientation revealed an ingroup enhancement and outgroup

Nicholas O. Rule; Nalini Ambady; Reginald B. Adams; C. Neil Macrae

2007-01-01

13

Variability in visual working memory ability limits the efficiency of perceptual decision making  

PubMed Central

The ability to make rapid and accurate decisions based on limited sensory information is a critical component of visual cognition. Available evidence suggests that simple perceptual discriminations are based on the accumulation and integration of sensory evidence over time. However, the memory system(s) mediating this accumulation are unclear. One candidate system is working memory (WM), which enables the temporary maintenance of information in a readily accessible state. Here, we show that individual variability in WM capacity is strongly correlated with the speed of evidence accumulation in speeded two-alternative forced choice tasks. This relationship generalized across different decision-making tasks, and could not be easily explained by variability in general arousal or vigilance. Moreover, we show that performing a difficult discrimination task while maintaining a concurrent memory load has a deleterious effect on the latter, suggesting that WM storage and decision making are directly linked. PMID:24695991

Ester, Edward F.; Ho, Tiffany C.; Brown, Scott D.; Serences, John T.

2014-01-01

14

Revisiting a Cognitive Framework for Test Design: Applications for a Computerized Perceptual Speed Test.  

ERIC Educational Resources Information Center

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

Alderton, David L.

15

Fluency effects in recognition memory: are perceptual fluency and conceptual fluency interchangeable?  

PubMed

On a recognition memory test, both perceptual and conceptual fluency can engender a sense of familiarity and elicit recognition memory illusions. To date, perceptual and conceptual fluency have been studied separately but are they interchangeable in terms of their influence on recognition judgments? Five experiments compared the effect of perceptual and conceptual fluency on recognition. The results suggest that under standard intentional encoding instructions participants were influenced by conceptual and perceptual fluency manipulations to a similar degree (Experiments 1a and 1b). When the perceptual features of the stimuli were emphasized during encoding, the perceptual fluency manipulation had a stronger influence on recognition memory decisions than the conceptual fluency manipulation (Experiment 2). Enhanced conceptual processing at encoding served to nullify the influence of both perceptual and conceptual fluency on the test (Experiment 3). The nature of the test instructions also influenced the relative contribution of perceptual versus conceptual fluency manipulations to the recognition judgment. In Experiment 4, the influence of conceptual fluency was larger when the recognition instructions were meaning based (a synonym recognition test) than with standard recognition instructions. Collectively, the results suggest that the relative contribution of perceptual and conceptual fluency depends on both encoding and test factors. PMID:24001021

Lanska, Meredith; Olds, Justin M; Westerman, Deanne L

2014-01-01

16

Poor anchoring limits dyslexics' perceptual, memory, and reading skills.  

PubMed

The basic deficits underlying the severe and persistent reading difficulties in dyslexia are still highly debated. One of the major topics of debate is whether these deficits are language specific, or affect both verbal and non-verbal stimuli. Recently, Ahissar and colleagues proposed the "anchoring-deficit hypothesis" (Ahissar, Lubin, Putter-Katz, & Banai, 2006), which suggests that dyslexics have a general difficulty in automatic extraction of stimulus regularities from auditory inputs. This hypothesis explained a broad range of dyslexics' verbal and non-verbal difficulties. However, it was not directly tested in the context of reading and verbal memory, which poses the main stumbling blocks to dyslexics. Here we assessed the abilities of adult dyslexics to efficiently benefit from ("anchor to") regularities embedded in repeated tones, orally presented syllables, and written words. We also compared dyslexics' performance to that of individuals with attention disorder (ADHD), but no reading disability. We found an anchoring effect in all groups: all gained from stimulus repetition. However, in line with the anchoring-deficit hypothesis, controls and ADHD participants showed a significantly larger anchoring effect in all tasks. This study is the first that directly shows that the same domain-general deficit, poor anchoring, characterizes dyslexics' performance in perceptual, working memory and reading tasks. PMID:22561890

Oganian, Yulia; Ahissar, Merav

2012-07-01

17

Perceptual chunking and its effect on memory in speech processing: ERP and behavioral evidence  

PubMed Central

We examined how perceptual chunks of varying size in utterances can influence immediate memory of heard items (monosyllabic words). Using behavioral measures and event-related potentials (N400) we evaluated the quality of the memory trace for targets taken from perceived temporal groups (TGs) of three and four items. Variations in the amplitude of the N400 showed a better memory trace for items presented in TGs of three compared to those in groups of four. Analyses of behavioral responses along with P300 components also revealed effects of chunk position in the utterance. This is the first study to measure the online effects of perceptual chunks on the memory trace of spoken items. Taken together, the N400 and P300 responses demonstrate that the perceptual chunking of speech facilitates information buffering and a processing on a chunk-by-chunk basis. PMID:24678304

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

2014-01-01

18

Beyond perceptual load and dilution: a review of the role of working memory in selective attention  

PubMed Central

The perceptual load and dilution models differ fundamentally in terms of the proposed mechanism underlying variation in distractibility during different perceptual conditions. However, both models predict that distracting information can be processed beyond perceptual processing under certain conditions, a prediction that is well-supported by the literature. Load theory proposes that in such cases, where perceptual task aspects do not allow for sufficient attentional selectivity, the maintenance of task-relevant processing depends on cognitive control mechanisms, including working memory. The key prediction is that working memory plays a role in keeping clear processing priorities in the face of potential distraction, and the evidence reviewed and evaluated in a meta-analysis here supports this claim, by showing that the processing of distracting information tends to be enhanced when load on a concurrent task of working memory is high. Low working memory capacity is similarly associated with greater distractor processing in selective attention, again suggesting that the unavailability of working memory during selective attention leads to an increase in distractibility. Together, these findings suggest that selective attention against distractors that are processed beyond perception depends on the availability of working memory. Possible mechanisms for the effects of working memory on selective attention are discussed. PMID:23734139

de Fockert, Jan W.

2013-01-01

19

Working memory, perceptual priming, and the perception of hierarchical forms: opposite effects of priming and working memory without memory refreshing.  

PubMed

Previous research has shown that stimuli held in working memory (WM) can influence spatial attention. Using Navon stimuli, we explored whether and how items in WM affect the perception of visual targets at local and global levels in compound letters. Participants looked for a target letter presented at a local or global level while holding a regular block letter as a memory item. An effect of holding the target's identity in WM was found. When memory items and targets were the same, performance was better than in a neutral condition when the memory item did not appear in the hierarchical letter (a benefit from valid cuing). When the memory item matched the distractor in the hierarchical stimulus, performance was worse than in the neutral baseline (a cost on invalid trials). These effects were greatest when the WM cue matched the global level of the hierarchical stimulus, suggesting that WM biases attention to the global level of form. Interestingly, in a no-memory priming condition, target perception was faster in the invalid condition than in the neutral baseline, reversing the effect in the WM condition. A further control experiment ruled out the effects of WM being due to participants' refreshing their memory from the hierarchical stimulus display. The data show that information in WM biases the selection of hierarchical forms, whereas priming does not. Priming alters the perceptual processing of repeated stimuli without biasing attention. PMID:20675799

Kim, Jeong-Im; Humphreys, Glyn W

2010-08-01

20

Further Explorations of Perceptual Speed Abilities in the Context of Assessment Methods, Cognitive Abilities, and Individual Differences During Skill Acquisition  

Microsoft Academic Search

Measures of perceptual speed ability have been shown to be an important part of assessment batteries for predicting performance on tasks and jobs that require a high level of speed and accuracy. However, traditional measures of perceptual speed ability sometimes have limited cost-effectiveness because of the requirements for administration and scoring of paper-and-pencil tests. There have also been concerns about

Phillip L. Ackerman; Margaret E. Beier

2007-01-01

21

Selection and Storage of Perceptual Groups Is Constrained by a Discrete Resource in Working Memory  

ERIC Educational Resources Information Center

Perceptual grouping can lead observers to perceive a multielement scene as a smaller number of hierarchical units. Past work has shown that grouping enables more elements to be stored in visual working memory (WM). Although this may appear to contradict so-called discrete resource models that argue for fixed item limits in WM storage, it is also…

Anderson, David E.; Vogel, Edward K.; Awh, Edward

2013-01-01

22

Differentiation of perceptual and semantic subsequent memory effects using an orthographic paradigm.  

PubMed

This study aimed to differentiate perceptual and semantic encoding processes using subsequent memory effects (SMEs) elicited by the recognition of orthographs of single Chinese characters. Participants studied a series of Chinese characters perceptually (by inspecting orthographic components) or semantically (by determining the object making sounds), and then made studied or unstudied judgments during the recognition phase. Recognition performance in terms of d-prime measure in the semantic condition was higher, though not significant, than that of the perceptual condition. The between perceptual-semantic condition differences in SMEs at P550 and late positive component latencies (700-1000ms) were not significant in the frontal area. An additional analysis identified larger SME in the semantic condition during 600-1000ms in the frontal pole regions. These results indicate that coordination and incorporation of orthographic information into mental representation is essential to both task conditions. The differentiation was also revealed in earlier SMEs (perceptual>semantic) at N3 (240-360ms) latency, which is a novel finding. The left-distributed N3 was interpreted as more efficient processing of meaning with semantically learned characters. Frontal pole SMEs indicated strategic processing by executive functions, which would further enhance memory. PMID:23063888

Kuo, Michael C C; Liu, Karen P Y; Ting, Kin Hung; Chan, Chetwyn C H

2012-11-27

23

Selection and Storage of Perceptual Groups Is Constrained by a Discrete Resource in Working Memory  

PubMed Central

Perceptual grouping can lead observers to perceive a multielement scene as a smaller number of hierarchical units. Past work has shown that grouping enables more elements to be stored in visual working memory (WM). Although this may appear to contradict so-called discrete resource models that argue for fixed item limits in WM storage, it is also possible that grouping reduces the effective number of “items” in the display. To test this hypothesis, we examined how mnemonic resolution declined as the number of items to be stored increased. Discrete resource models predict that precision will reach a stable plateau at relatively early set sizes, because no further items can be stored once putative item limits are exceeded. Thus, we examined whether the precision by set size function was bilinear when storage was enhanced via perceptual grouping. In line with the hypothesis that each perceptual group counted as a single “item,” precision still reached a clear plateau at a set size determined by the number of stored groups. Moreover, the maximum number of elements stored was doubled, and electrophysiological measures showed that selection and storage-related neural responses were the same for a single element and a multielement perceptual group. Thus, perceptual grouping allows more elements to be held in working memory while storage is still constrained by a discrete item limit. PMID:23067117

Anderson, David E.; Vogel, Edward K.; Awh, Edward

2014-01-01

24

Memory's aging echo: age-related decline in neural reactivation of perceptual details during recollection.  

PubMed

Episodic memory decline is a hallmark of normal cognitive aging. Here, we report the first event-related fMRI study to directly investigate age differences in the neural reactivation of qualitatively rich perceptual details during recollection. Younger and older adults studied pictures of complex scenes at different presentation durations along with descriptive verbal labels, and these labels subsequently were used during fMRI scanning to cue picture recollections of varying perceptual detail. As expected from prior behavioral work, the two age groups subjectively rated their recollections as containing similar amounts of perceptual detail, despite objectively measured recollection impairment in older adults. In both age groups, comparisons of retrieval trials that varied in recollected detail revealed robust activity in brain regions previously linked to recollection, including hippocampus and both medial and lateral regions of the prefrontal and posterior parietal cortex. Critically, this analysis also revealed recollection-related activity in visual processing regions that were active in an independent picture-perception task, and these regions showed age-related reductions in activity during recollection that cannot be attributed to age differences in response criteria. These fMRI findings provide new evidence that aging reduces the absolute quantity of perceptual details that are reactivated from memory, and they help to explain why aging reduces the reliability of subjective memory judgments. PMID:24828546

McDonough, Ian M; Cervantes, Sasha N; Gray, Stephen J; Gallo, David A

2014-09-01

25

Working Memory Does Not Dissociate between Different Perceptual Categorization Tasks  

ERIC Educational Resources Information Center

Working memory is crucial for many higher level cognitive functions, ranging from mental arithmetic to reasoning and problem solving. Likewise, the ability to learn and categorize novel concepts forms an indispensable part of human cognition. However, very little is known about the relationship between working memory and categorization. This…

Lewandowsky, Stephan; Yang, Lee-Xieng; Newell, Ben R.; Kalish, Michael L.

2012-01-01

26

Action video games do not improve the speed of information processing in simple perceptual tasks.  

PubMed

Previous research suggests that playing action video games improves performance on sensory, perceptual, and attentional tasks. For instance, Green, Pouget, and Bavelier (2010) used the diffusion model to decompose data from a motion detection task and estimate the contribution of several underlying psychological processes. Their analysis indicated that playing action video games leads to faster information processing, reduced response caution, and no difference in motor responding. Because perceptual learning is generally thought to be highly context-specific, this transfer from gaming is surprising and warrants corroborative evidence from a large-scale training study. We conducted 2 experiments in which participants practiced either an action video game or a cognitive game in 5 separate, supervised sessions. Prior to each session and following the last session, participants performed a perceptual discrimination task. In the second experiment, we included a third condition in which no video games were played at all. Behavioral data and diffusion model parameters showed similar practice effects for the action gamers, the cognitive gamers, and the nongamers and suggest that, in contrast to earlier reports, playing action video games does not improve the speed of information processing in simple perceptual tasks. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PMID:24933517

van Ravenzwaaij, Don; Boekel, Wouter; Forstmann, Birte U; Ratcliff, Roger; Wagenmakers, Eric-Jan

2014-10-01

27

Processing Speed Mediates Gender Differences in Memory in Schizophrenia  

Microsoft Academic Search

The primary aim of this study was to examine whether processing speed mediates the association between gender and episodic memory in schizophrenia. Participants were 51 female and 51 male outpatients comparable on demographic, clinical, and cognitive variables. Memory tests included both verbal and visual measures. Both groups scored below the normative mean of the memory and processing speed tests, except

Pei-Chun Tsai; Joan McDowd; Tze-Chun Tang; Chwen-Yng Su

2012-01-01

28

Repetition Priming in Speeded Word Reading: Contributions of Perceptual and Conceptual Processing Episodes  

Microsoft Academic Search

Five experiments investigated repetition priming on an indirect speeded word reading (naming) test, a task intended to circumvent conscious recollection. Reading a word or generating it from a semantic cue (either a phrase or an antonym) produced reliable priming of similar magnitude on this indirect test of memory. Efforts to encourage conscious recollection elevated response latencies in speeded reading and

Colin M MacLeod; Michael E. J. Masson

2000-01-01

29

Infant Visual Recognition Memory: Independent Contributions of Speed and Attention  

Microsoft Academic Search

Relations between infant visual recognition memory and later cognition have fueled interest in identifying the underlying cognitive components of this important infant ability. The present large-scale study examined three promising factors in this regard—processing speed, short-term memory capacity, and attention. Two of these factors, attention and processing speed (but, surprisingly, not short-term memory capacity), were related to visual recognition memory:

Susan A. Rose; Judith F. Feldman; Jeffery J. Jankowski

2003-01-01

30

The Comparison of Visual Working Memory Representations with Perceptual Inputs  

PubMed Central

The human visual system can notice differences between memories of previous visual inputs and perceptions of new visual inputs, but the comparison process that detects these differences has not been well characterized. This study tests the hypothesis that differences between the memory of a stimulus array and the perception of a new array are detected in a manner that is analogous to the detection of simple features in visual search tasks. That is, just as the presence of a task-relevant feature in visual search can be detected in parallel, triggering a rapid shift of attention to the object containing the feature, the presence of a memory-percept difference along a task-relevant dimension can be detected in parallel, triggering a rapid shift of attention to the changed object. Supporting evidence was obtained in a series of experiments that examined manual reaction times, saccadic reaction times, and event-related potential latencies. However, these experiments also demonstrated that a slow, limited-capacity process must occur before the observer can make a manual change-detection response. PMID:19653755

Hyun, Joo-seok; Woodman, Geoffrey F.; Vogel, Edward K.; Hollingworth, Andrew

2008-01-01

31

Involvement of the cholinergic system in conditioning and perceptual memory.  

PubMed

The cholinergic systems play a pivotal role in learning and memory, and have been the centre of attention when it comes to diseases containing cognitive deficits. It is therefore not surprising, that the cholinergic transmitter system has experienced detailed examination of its role in numerous behavioural situations not least with the perspective that cognition may be rescued with appropriate cholinergic 'boosters'. Here we reviewed the literature on (i) cholinergic lesions, (ii) pharmacological intervention of muscarinic or nicotinic system, or (iii) genetic deletion of selective receptor subtypes with respect to sensory discrimination and conditioning procedures. We consider visual, auditory, olfactory and somatosensory processing first before discussing more complex tasks such as startle responses, latent inhibition, negative patterning, eye blink and fear conditioning, and passive avoidance paradigms. An overarching reoccurring theme is that lesions of the cholinergic projection neurones of the basal forebrain impact negatively on acquisition learning in these paradigms and blockade of muscarinic (and to a lesser extent nicotinic) receptors in the target structures produce similar behavioural deficits. While these pertain mainly to impairments in acquisition learning, some rare cases extend to memory consolidation. Such single case observations warranted replication and more in-depth studies. Intriguingly, receptor blockade or receptor gene knockout repeatedly produced contradictory results (for example in fear conditioning) and combined studies, in which genetically altered mice are pharmacological manipulated, are so far missing. However, they are desperately needed to clarify underlying reasons for these contradictions. Consistently, stimulation of either muscarinic (mainly M(1)) or nicotinic (predominantly ?7) receptors was beneficial for learning and memory formation across all paradigms supporting the notion that research into the development and mechanisms of novel and better cholinomimetics may prove useful in the treatment of neurodegenerative or psychiatric disorders with cognitive endophenotypes. PMID:21315109

Robinson, Lianne; Platt, Bettina; Riedel, Gernot

2011-08-10

32

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

PubMed Central

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. PMID:23850685

Censor, Nitzan

2013-01-01

33

Bias in self-motion perceived speed can enhance episodic memory.  

PubMed

Prior experiences of a stimulus facilitate reprocessing of that stimulus on a subsequent occasion. This relative ease and speed with which information is processed is defined as fluency and can constitute a basis for memory judgment. Fluency can also be manipulated on line by perceptual bias (e.g., levels of noise), leading to an increase in recognition for items processed more fluently (e.g., items with less noise). Previous experiments using Remember-Know paradigm have shown an impact of perceptual fluency only on familiarity and not on recollection. Recent episodic memory models have postulated a strong link between episodic memory and spatial processes, especially with egocentric updating (Gomez et al. in Acta Psychol 132(3):221-227, 2009). The present experiment was conducted to determine whether self-motion fluency affects recognition performance and particularly has an impact on "Remember" responses. Thirty participants learned a 4-min path movie and then had to recognize among short paths if they were part of the learned path, followed by a Remember-Know procedure for recognized items. Self-motion fluency was manipulated with the presence of nimble acceleration applied on a small part of the recognition paths. Results show that the presence of a self-motion fluency increases significantly the proportion of remember responses solely on learned paths. This study spotlights for the first time a specific fluency effect on recollection and indicates an implication of egocentric-updating processing in episodic memory retrieval. PMID:22806647

Cerles, Mélanie; Rousset, Stéphane

2012-08-01

34

Teaching memory-impaired people to touch type: The acquisition of a useful complex perceptual-motor skill  

Microsoft Academic Search

This study provides ecological validity for laboratory findings that people with memory difficulties following brain injury can learn new skills. This was done by testing the acquisition of a useful real-world perceptual-motor skill. Using a conventional computer software training package supplemented by one-to-one coaching, a woman with severely impaired memory and a man with poor memory learned to touch type.

Mary Todd; Corinne Barrow

2008-01-01

35

Working memory is related to perceptual processing: A case from color perception  

PubMed Central

We explored the relation between individual differences in working memory (WM) and color constancy, the phenomenon of color perception that allows us to perceive the color of an object as relatively stable under changes in illumination. Successive color constancy (measured by first viewing a colored surface under a particular illumination and later recalling it under a new illumination) was better for higher-WM individuals than for lower-WM individuals. Moreover, the magnitude of this WM difference depended on how much contextual information was available in the scene, which typically improves color constancy. By contrast, simple color memory, measured by viewing and recalling a colored surface under the same illumination, showed no significant relation to WM. This study reveals a relation between WM and a low-level perceptual process not previously thought to operate within the confines of attentional control, and provides a first account of the individual differences in color constancy known about for decades. PMID:21480748

Allen, Elizabeth C.; Beilock, Sian L.; Shevell, Steven K.

2011-01-01

36

Well-Being Affects Changes in Perceptual Speed in Advanced Old Age: Longitudinal Evidence for a Dynamic Link  

ERIC Educational Resources Information Center

This study examined competing hypotheses about dynamic cross-domain associations between perceptual speed and well-being in advanced old age. We applied the bivariate dual change score model (J. J. McArdle & F. Hamagami, 2001) to 13-year incomplete longitudinal data from the Berlin Aging Study (P. B. Baltes & K. U. Mayer, 1999; N = 516, 70-103…

Gerstorf, Denis; Lovden, Martin; Rocke, Christina; Smith, Jacqui; Lindenberger, Ulman

2007-01-01

37

Processing speed interacts with working memory efficiency in multiple sclerosis.  

PubMed

Information processing speed was assessed using the visual threshold serial addition test (VT-SAT), a computerized modification of the PASAT designed to assess processing speed by controlling for performance accuracy. Persons with MS (N=43) and healthy individuals (N=32) were administered the VT-SAT varying working memory loads (1-back versus 2-back). Results indicated that at the lower working memory load (1-back) all individuals with MS were able to achieve a working memory performance level equivalent to healthy individuals, but required significantly more processing time to do so. In contrast, at the higher working memory load (2-back), about 70% of MS participants were able to achieve a performance level equivalent to healthy individuals, but again required significantly more processing time. The results are discussed in the context of the dynamic nature of the relationship between processing speed and working memory performance, emphasizing the dependence of this relationship on other cognitive and disease-related factors. PMID:16564670

Lengenfelder, Jean; Bryant, Deborah; Diamond, Bruce J; Kalmar, Jessica H; Moore, Nancy B; DeLuca, John

2006-04-01

38

Processing Speed, Attentional Capacity, and Age-Related Memory Change  

Microsoft Academic Search

This study compared the relative importance (i.e., proportion of shared variance) of attentional capacity and processing speed accounts of cognitive aging to predict age differences in episodic and working memory performance. Right-handed adults (n = 100), 18 to 88 years of age, completed measures of attentional capacity (divided attention), processing speed, and episodic and working memory. The results provide little support for

Terry Levitt; Jonathan Fugelsang; Margaret Crossley

2006-01-01

39

Working Memory Influences Processing Speed and Reading Fluency in ADHD  

PubMed Central

Processing speed deficits affect reading efficiency, even among individuals who recognize and decode words accurately. Children with ADHD who decode words accurately can still have inefficient reading fluency, leading to a bottleneck in other cognitive processes. This “slowing” in ADHD is associated with deficits in fundamental components of executive function underlying processing speed, including response selection. The purpose of the present study was to deconstruct processing speed in order to determine which components of executive control best explain the “processing” speed deficits related to reading fluency in ADHD. Participants (41 ADHD, 21 controls), ages 9-14, screened for language disorders, word reading deficits, and psychiatric disorders, were administered measures of copying speed, processing speed, reading fluency, working memory, reaction time, inhibition, and auditory attention span. Compared to controls, children with ADHD showed reduced oral and silent reading fluency, and reduced processing speed—driven primarily by deficits on WISC-IV Coding. In contrast, groups did not differ on copying speed. After controlling for copying speed, sex, severity of ADHD-related symptomatology, and GAI, slowed “processing” speed (i.e., Coding) was significantly associated with verbal span and measures of working memory, but not with measures of response control/inhibition, lexical retrieval speed, reaction time, or intra-subject variability. Further, “processing” speed (i.e., Coding, residualized for copying speed) and working memory were significant predictors of oral reading fluency. Abnormalities in working memory and response selection (which are frontally-mediated and enter into the output side of processing speed) may play an important role in deficits in reading fluency in ADHD, potentially more than posteriorally-mediated problems with orienting of attention or perceiving the stimulus. PMID:21287422

Jacobson, Lisa A.; Ryan, Matthew; Martin, Rebecca B.; Ewen, Joshua; Mostofsky, Stewart H.; Denckla, Martha B.; Mahone, E. Mark

2012-01-01

40

Language and short-term memory: the role of perceptual-motor affordance.  

PubMed

The advantage for real words over nonwords in serial recall--the lexicality effect--is typically attributed to support for item-level phonology, either via redintegration, whereby partially degraded short-term traces are "cleaned up" via support from long-term representations of the phonological material or via the more robust temporary activation of long-term lexical phonological knowledge that derives from its combination with established lexical and semantic levels of representation. The much smaller effect of lexicality in serial recognition, where the items are re-presented in the recognition cue, is attributed either to the minimal role for redintegration from long-term memory or to the minimal role for item memory itself in such retrieval conditions. We show that the reduced lexicality effect in serial recognition is not a function of the retrieval conditions, but rather because previous demonstrations have used auditory presentation, and we demonstrate a robust lexicality effect for visual serial recognition in a setting where auditory presentation produces no such effect. Furthermore, this effect is abolished under conditions of articulatory suppression. We argue that linguistic knowledge affects the readiness with which verbal material is segmentally recoded via speech motor processes that support rehearsal and therefore affects tasks that involve recoding. On the other hand, auditory perceptual organization affords sequence matching in the absence of such a requirement for segmental recoding and therefore does not show such effects of linguistic knowledge. PMID:24797440

Macken, Bill; Taylor, John C; Jones, Dylan M

2014-09-01

41

High-speed spatially multimode atomic memory  

SciTech Connect

We study the coherent storage and retrieval of a very short multimode light pulse in an atomic ensemble. We consider a quantum memory process based on the conversion of a signal pulse into a long-lived spin coherence via light matter interaction in an on-resonant {Lambda} -type system. In order to study the writing and reading processes we analytically solve the partial differential equations describing the evolution of the field and of the atomic coherence in time as well as in space. We show how to optimize the process for writing as well as for reading. If the medium length is fixed, for each length, there is an optimal value of the pulse duration. We discuss the information capacity of this memory scheme and we estimate the number of transverse modes that can be stored as a quantum hologram.

Golubeva, T.; Golubev, Yu.; Mishina, O.; Bramati, A.; Laurat, J.; Giacobino, E. [St. Petersburg State University, 198504 St. Petersburg, Stary Petershof, ul. Ul'yanovskaya, 1 (Russian Federation); Laboratoire Kastler Brossel, Universite Pierre et Marie Curie, Ecole Normale Superieure, CNRS, Case 74, 4 place Jussieu, F-75252 Paris Cedex 05 (France)

2011-05-15

42

Breaking the speed limits of phase-change memory.  

PubMed

Phase-change random-access memory (PCRAM) is one of the leading candidates for next-generation data-storage devices, but the trade-off between crystallization (writing) speed and amorphous-phase stability (data retention) presents a key challenge. We control the crystallization kinetics of a phase-change material by applying a constant low voltage via prestructural ordering (incubation) effects. A crystallization speed of 500 picoseconds was achieved, as well as high-speed reversible switching using 500-picosecond pulses. Ab initio molecular dynamics simulations reveal the phase-change kinetics in PCRAM devices and the structural origin of the incubation-assisted increase in crystallization speed. This paves the way for achieving a broadly applicable memory device, capable of nonvolatile operations beyond gigahertz data-transfer rates. PMID:22723419

Loke, D; Lee, T H; Wang, W J; Shi, L P; Zhao, R; Yeo, Y C; Chong, T C; Elliott, S R

2012-06-22

43

Granger causality analysis reveals distinct spatio-temporal connectivity patterns in motor and perceptual visuo-spatial working memory  

PubMed Central

We employed spectral Granger causality analysis on a full set of 56 electroencephalographic recordings acquired during the execution of either a 2D movement pointing or a perceptual (yes/no) change detection task with memory and non-memory conditions. On the basis of network characteristics across frequency bands, we provide evidence for the full dissociation of the corresponding cognitive processes. Movement-memory trial types exhibited higher degree nodes during the first 2 s of the delay period, mainly at central, left frontal and right-parietal areas. Change detection-memory trial types resulted in a three-peak temporal pattern of the total degree with higher degree nodes emerging mainly at central, right frontal, and occipital areas. Functional connectivity networks resulting from non-memory trial types were characterized by more sparse structures for both tasks. The movement-memory trial types encompassed an apparent coarse flow from frontal to parietal areas while the opposite flow from occipital, parietal to central and frontal areas was evident for the change detection-memory trial types. The differences among tasks and conditions were more profound in ? (8–12 Hz) and ? (12–30 Hz) and less in ? (30–45 Hz) band. Our results favor the hypothesis which considers spatial working memory as a by-product of specific mental processes that engages common brain areas under different network organizations.

Protopapa, Foteini; Siettos, Constantinos I.; Evdokimidis, Ioannis; Smyrnis, Nikolaos

2014-01-01

44

Working memory, perceptual priming, and the perception of hierarchical forms: Opposite effects of priming and working memory without memory refreshing  

Microsoft Academic Search

Previous research has shown that stimuli held in working memory (WM) can influence spatial attention. Using Navon stimuli,\\u000a we explored whether and how items in WM affect the perception of visual targets at local and global levels in compound letters.\\u000a Participants looked for a target letter presented at a local or global level while holding a regular block letter as

Jeong-Im Kim; Glyn W. Humphreys

2010-01-01

45

Prediction, postdiction, and perceptual length contraction: a bayesian low-speed prior captures the cutaneous rabbit and related illusions.  

PubMed

Illusions provide a window into the brain's perceptual strategies. In certain illusions, an ostensibly task-irrelevant variable influences perception. For example, in touch as in audition and vision, the perceived distance between successive punctate stimuli reflects not only the actual distance but curiously the inter-stimulus time. Stimuli presented at different positions in rapid succession are drawn perceptually toward one another. This effect manifests in several illusions, among them the startling cutaneous rabbit, in which taps delivered to as few as two skin positions appear to hop progressively from one position to the next, landing in the process on intervening areas that were never stimulated. Here we provide an accessible step-by-step exposition of a Bayesian perceptual model that replicates the rabbit and related illusions. The Bayesian observer optimally joins uncertain estimates of spatial location with the expectation that stimuli tend to move slowly. We speculate that this expectation - a Bayesian prior - represents the statistics of naturally occurring stimuli, learned by humans through sensory experience. In its simplest form, the model contains a single free parameter, tau: a time constant for space perception. We show that the Bayesian observer incorporates both pre- and post-dictive inference. Directed spatial attention affects the prediction-postdiction balance, shifting the model's percept toward the attended location, as observed experimentally in humans. Applying the model to the perception of multi-tap sequences, we show that the low-speed prior fits perception better than an alternative, low-acceleration prior. We discuss the applicability of our model to related tactile, visual, and auditory illusions. To facilitate future model-driven experimental studies, we present a convenient freeware computer program that implements the Bayesian observer; we invite investigators to use this program to create their own testable predictions. PMID:23675360

Goldreich, Daniel; Tong, Jonathan

2013-01-01

46

Prediction, Postdiction, and Perceptual Length Contraction: A Bayesian Low-Speed Prior Captures the Cutaneous Rabbit and Related Illusions  

PubMed Central

Illusions provide a window into the brain’s perceptual strategies. In certain illusions, an ostensibly task-irrelevant variable influences perception. For example, in touch as in audition and vision, the perceived distance between successive punctate stimuli reflects not only the actual distance but curiously the inter-stimulus time. Stimuli presented at different positions in rapid succession are drawn perceptually toward one another. This effect manifests in several illusions, among them the startling cutaneous rabbit, in which taps delivered to as few as two skin positions appear to hop progressively from one position to the next, landing in the process on intervening areas that were never stimulated. Here we provide an accessible step-by-step exposition of a Bayesian perceptual model that replicates the rabbit and related illusions. The Bayesian observer optimally joins uncertain estimates of spatial location with the expectation that stimuli tend to move slowly. We speculate that this expectation – a Bayesian prior – represents the statistics of naturally occurring stimuli, learned by humans through sensory experience. In its simplest form, the model contains a single free parameter, tau: a time constant for space perception. We show that the Bayesian observer incorporates both pre- and post-dictive inference. Directed spatial attention affects the prediction-postdiction balance, shifting the model’s percept toward the attended location, as observed experimentally in humans. Applying the model to the perception of multi-tap sequences, we show that the low-speed prior fits perception better than an alternative, low-acceleration prior. We discuss the applicability of our model to related tactile, visual, and auditory illusions. To facilitate future model-driven experimental studies, we present a convenient freeware computer program that implements the Bayesian observer; we invite investigators to use this program to create their own testable predictions. PMID:23675360

Goldreich, Daniel; Tong, Jonathan

2013-01-01

47

High speed, nondestructive readout from thin-film ferroelectric memory  

NASA Technical Reports Server (NTRS)

High-speed polarization-direction-dependent photoresponse from ferroelectric lead zirconate titanate (PbZr(0.53)Ti(0.47)O3) thin films sandwiched between conducting electrodes to form a memory capacitor is reported. Laser pulses with a full width at half maximum of around 10 ns at 532-nm wavelength are utilized to readout the photoresponse signal from individual polarized elements. Such readout is repeated over a million times, with no detectable degradation in the photoresponse or the remanent polarization suggesting its potential as a nondestructive readout (NDRO) of nonvolatile polarization state in thin-film ferroelectric memories. In principle both electronic as well as thermal mechanisms could be triggered by such photon exposure of ferroelectric thin films. A comparison of the photoresponse from capacitors with semitransparent and opaque top electrodes suggests that the observed NDRO signal is primarily due to thermally triggered mechanisms.

Thakoor, Sarita

1992-01-01

48

A latent variables examination of processing speed, response inhibition, and working memory during typical development  

Microsoft Academic Search

This study addressed three related aims: (a) to replicate and extend previous work regarding the nonunitary nature of processing speed, response inhibition, and working memory during development; (b) to quantify the rate at which processing speed, response inhibition, and working memory develop and the extent to which the development of these latter abilities reflect general changes in processing speed; and

Tara McAuley; Desirée A. White

2011-01-01

49

Relationship of Encoding Speed and Memory Tests to Flight Training Performance.  

National Technical Information Service (NTIS)

The demands on the cognitive/perceptual abilities of military pilots have increased steadily as aircraft have become more sophisticated. The ability to encode and classify signals and to retrieve information from short-term memory are two of the several c...

T. R. Carretta

1988-01-01

50

Effects of Animation's Speed of Presentation on Perceptual Processing and Learning  

ERIC Educational Resources Information Center

Animations presented at different speed are assumed to differentially interact with learners' perception and cognition due to the constraints imposed by learners' limited sensitivity to incoming dynamic information. To investigate the effects of high and low presentation speed of animation, two studies were conducted. In Study 1, participants were…

Meyer, Katja; Rasch, Thorsten; Schnotz, Wolfgang

2010-01-01

51

FoxP influences the speed and accuracy of a perceptual decision in Drosophila.  

PubMed

Decisions take time if information gradually accumulates to a response threshold, but the neural mechanisms of integration and thresholding are unknown. We characterized a decision process in Drosophila that bears the behavioral signature of evidence accumulation. As stimulus contrast in trained odor discriminations decreased, reaction times increased and perceptual accuracy declined, in quantitative agreement with a drift-diffusion model. FoxP mutants took longer than wild-type flies to form decisions of similar or reduced accuracy, especially in difficult, low-contrast tasks. RNA interference with FoxP expression in ?? core Kenyon cells, or the overexpression of a potassium conductance in these neurons, recapitulated the FoxP mutant phenotype. A mushroom body subdomain whose development or function require the transcription factor FoxP thus supports the progression of a decision toward commitment. PMID:24855268

DasGupta, Shamik; Ferreira, Clara Howcroft; Miesenböck, Gero

2014-05-23

52

FoxP Influences the Speed and Accuracy of a Perceptual Decision in Drosophila+  

PubMed Central

Decisions take time if information gradually accumulates to a response threshold, but the neural mechanisms of integration and thresholding are unknown. We characterized a decision process in Drosophila that bears the behavioral signature of evidence accumulation. As stimulus contrast in trained odor discriminations decreased, reaction times increased and perceptual accuracy declined, in quantitative agreement with a drift-diffusion model. FoxP mutants took longer than wild-type flies to form decisions of similar or reduced accuracy, especially in difficult, low-contrast tasks. RNAi knock-down of FoxP in ?? core Kenyon cells, or the overexpression of a potassium conductance in these neurons, recapitulated the FoxP mutant phenotype. A mushroom body subdomain whose development or function require the transcription factor FoxP thus supports the progression of a decision towards commitment. PMID:24855268

DasGupta, Shamik; Ferreira, Clara Howcroft; Miesenbock, Gero

2014-01-01

53

Your brain on speed: cognitive performance of a spatial working memory task is not affected by walking speed  

PubMed Central

When humans walk in everyday life, they typically perform a range of cognitive tasks while they are on the move. Past studies examining performance changes in dual cognitive-motor tasks during walking have produced a variety of results. These discrepancies may be related to the type of cognitive task chosen, differences in the walking speeds studied, or lack of controlling for walking speed. The goal of this study was to determine how young, healthy subjects performed a spatial working memory task over a range of walking speeds. We used high-density electroencephalography to determine if electrocortical activity mirrored changes in cognitive performance across speeds. Subjects stood (0.0 m/s) and walked (0.4, 0.8, 1.2, and 1.6 m/s) with and without performing a Brooks spatial working memory task. We hypothesized that performance of the spatial working memory task and the associated electrocortical activity would decrease significantly with walking speed. Across speeds, the spatial working memory task caused subjects to step more widely compared with walking without the task. This is typically a sign that humans are adapting their gait dynamics to increase gait stability. Several cortical areas exhibited power fluctuations time-locked to memory encoding during the cognitive task. In the somatosensory association cortex, alpha power increased prior to stimulus presentation and decreased during memory encoding. There were small significant reductions in theta power in the right superior parietal lobule and the posterior cingulate cortex around memory encoding. However, the subjects did not show a significant change in cognitive task performance or electrocortical activity with walking speed. These findings indicate that in young, healthy subjects walking speed does not affect performance of a spatial working memory task. These subjects can devote adequate cortical resources to spatial cognition when needed, regardless of walking speed. PMID:24847239

Kline, Julia E.; Poggensee, Katherine; Ferris, Daniel P.

2014-01-01

54

Music perception involves complex brain functions underlying feature extraction, perceptual grouping of these features, memory, processing of emotion, and so on.  

E-print Network

: Music perception involves complex brain functions underlying feature extraction, perceptual grouping of these features, memory, processing of emotion, and so on. Numerous studies used neuroimaging. Such superiority of musicians is based on long-term musical experience and several studies have found

Tanaka, Jiro

55

The Relationship Between IQ, Memory, Executive Function, and Processing Speed in Recent-Onset Psychosis: 1-Year Stability and Clinical Outcome  

E-print Network

Studies commonly report poor performance in psychotic patients compared with controls on tasks testing a range of cognitive functions, but, because current IQ is often not matched between these groups, it is difficult to determine whether this represents a generalized deficit or specific abnormalities. Fifty-three first-episode psychosis patients and 53 healthy controls, one-to-one matched for sex, age, and full-scale current IQ, were compared on Wechsler Adult Intelligence Scale (WAIS) subtests representing indices of perceptual organization, verbal comprehension, processing speed, and working memory as well as other tests of executive function and episodic memory. The groups showed an equivalent pattern of performance on all WAIS subtests except digit symbol processing speed, on which the patients were significantly worse. Patients

Verity C. Leeson; Thomas R. E. Barnes; Isobel Harrison; Stanley H. Mutsatsa; Maria A. Ron; Eileen M. Joyce

56

Histamine H1 receptor antagonist cetirizine impairs working memory processing speed, but not episodic memory  

PubMed Central

BACKGROUND AND PURPOSE The histaminergic neurotransmitter system is currently under investigation as a target for drug treatment of cognitive deficits in clinical disorders. The therapeutic potential of new drugs may initially be screened using a model of histaminergic dysfunction, for example, as associated with the use of centrally active antihistamines. Of the selective second generation antihistamines, cetirizine has been found to have central nervous system effects. The aim of the present study was to determine whether cetirizine can be used as a tool to model cognitive deficits associated with histaminergic hypofunction. EXPERIMENTAL APPROACH The study was conducted according to a three-way, double-blind, cross-over design. Treatments were single oral doses of cetirizine 10 and 20 mg and placebo. Effects on cognition were assessed using tests of word learning, memory scanning, vigilance, divided attention, tracking and visual information processing speed. KEY RESULTS Cetirizine 10 mg impaired tracking performance and both doses impaired memory scanning speed. None of the other measures indicated impaired performance. CONCLUSION AND IMPLICATIONS Cetirizine affects information processing speed, but these effects were not sufficient to serve as a model for cognitive deficits in clinical disorders. PMID:20735428

van Ruitenbeek, P; Vermeeren, A; Riedel, WJ

2010-01-01

57

Processing Speed: A Strong Predictor of Verbal Memory Performance in Schizophrenia  

Microsoft Academic Search

The role of slowing of processing speed in verbal memory impairment in patients with schizophrenia was investigated. Forty-one patients with schizophrenia and 41 healthy control subjects were administered a verbal memory task involving free recall of three lists of words, which varied in their degree of semantic organization. Standard processing speed tests were administered as well. Regression analyses were conducted

Gildas Brébion; Anthony S. David; Rodrigo A. Bressan; Lyn S. Pilowsky

2006-01-01

58

Genetic Covariance Among Measures of Information Processing Speed, Working Memory, and IQ  

Microsoft Academic Search

The genetic relationship between lower (information processing speed), intermediate (working memory), and higher levels (complex cognitive processes as indexed by IQ) of mental ability was studied in a classical twin design comprising 166 monozygotic and 190 dizygotic twin pairs. Processing speed was measured by a choice reaction time (RT) task (2-, 4-, and 8-choice), work- ing memory by a visual-spatial

M. Luciano; M. J. Wright; G. A. Smith; G. M. Geffen; L. B. Geffen; N. G. Martin

2001-01-01

59

Genetic Covariance Among Measures of Information Processing Speed, Working Memory, and IQ  

Microsoft Academic Search

The genetic relationship between lower (information processing speed), intermediate (working memory), and higher levels (complex cognitive processes as indexed by IQ) of mental ability was studied in a classical twin design comprising 166 monozygotic and 190 dizygotic twin pairs. Processing speed was measured by a choice reaction time (RT) task (2-, 4-, and 8-choice), working memory by a visual-spatial delayed

M. Luciano; M. J. Wright; G. A. Smith; G. M. Geffen; L. B. Geffen; N. G. Martin

2001-01-01

60

A Latent Variables Examination of Processing Speed, Response Inhibition, and Working Memory during Typical Development  

ERIC Educational Resources Information Center

This study addressed three related aims: (a) to replicate and extend previous work regarding the nonunitary nature of processing speed, response inhibition, and working memory during development; (b) to quantify the rate at which processing speed, response inhibition, and working memory develop and the extent to which the development of these…

McAuley, Tara; White, Desiree A.

2011-01-01

61

Perceptual Filtering in L2 Lexical Memory: A Neural Network Approach to Second Language Acquisition  

ERIC Educational Resources Information Center

A number of asymmetries in lexical memory emerge when monolinguals and early bilinguals are compared to (relatively) late second language (L2) learners. Their study promises to provide insight into the internal processes that both support and ultimately limit L2 learner achievement. Generally, theory building in L2 and bilingual lexical memory has…

Nelson, Robert

2012-01-01

62

ORIGINAL INVESTIGATION Memory and psychostimulants: modulation of Pavlovian  

E-print Network

take, displayed impaired conditioned freezing when tested off- drug. Alternately, subjects injected doses for attention deficit hyperactivity disorder, displayed enhanced memory when tested off-drug- amine abusers display worse performance on tests of word recall, perceptual speed, vocabulary

Anagnostaras, Stephan

63

A latent variable analysis of working memory capacity, short-term memory capacity, processing speed, and general fluid intelligence  

Microsoft Academic Search

Significant relationships exist between general fluid intelligence and each of the following constructs: short-term memory capacity, working memory capacity (WMC), and processing speed. However, the interrelationship among all four constructs has not been investigated. Multiple measures of each of these constructs were obtained from 120 healthy young adults. Structural equation modeling was then performed to determine which construct served as

Andrew R. A. Conway; Nelson Cowan; Michael F. Bunting; David J. Therriault; Scott R. B. Minkoff

64

A latent variable analysis of working memory capacity, short-term memory capacity, processing speed, and general fluid intelligence  

Microsoft Academic Search

Significant relationships exist between general fluid intelligence and each of the following constructs: short-term memory capacity, working memory capacity (WMC), and processing speed. However, the interrelationship among all four constructs has not been investigated. Multiple measures of each of these constructs were obtained from 120 healthy young adults. Structural equation modeling was then performed to determine which construct served as

Andrew R. a. Conway; Nelson Cowan; Michael F. Bunting; David J. Therriault; Scott R. b. Minkoff

2002-01-01

65

The role of visuospatial and verbal working memory in perceptual category learning  

Microsoft Academic Search

The role of verbal and visuospatial working memory in rule-based and information-integration category learning was examined.\\u000a Previously, Maddox, Ashby, Ing, and Pickering (2004) found that a sequentially presented verbal working memory task did not\\u000a affect information-integration learning, but disrupted rule-based learning when the rule was on the spatial frequency of a\\u000a Gabor stimulus. This pattern was replicated in Experiment 1,

Dagmar Zeithamova; W. Todd Maddox

2007-01-01

66

Longitudinal Changes in Memory Performance and Processing Speed in Old Age abstract Keywords  

Microsoft Academic Search

The speed theory of cognitive aging posits that an age-related slowing of processing speed leads to impairments in higher order cognitive functions, such as memory. However, only few studies have examined the relationship between longitudinal changes in processing speed and longitudinal changes in memory performance. In the present study, data of 474 older adults (T1: 59–65 years) from the Interdisciplinary

Ulrike Lemke; Daniel Zimprich

2005-01-01

67

Working Memory Is Related to Perceptual Processing: A Case from Color Perception  

ERIC Educational Resources Information Center

We explored the relation between individual differences in working memory (WM) and color constancy, the phenomenon of color perception that allows us to perceive the color of an object as relatively stable under changes in illumination. Successive color constancy (measured by first viewing a colored surface under a particular illumination and…

Allen, Elizabeth C.; Beilock, Sian L.; Shevell, Steven K.

2011-01-01

68

Is Speed of Processing or Working Memory the Primary Information Processing Deficit in Multiple Sclerosis?  

Microsoft Academic Search

Objective: To examine whether processing speed or working memory is the primary information processing deficit in persons with MS. Design: Case-control study. Setting: Hospital-based specialty clinic. Participants: 215 adults with clinically definite MS. Main Outcome Measure: Mean demographically corrected T-scores, prevalence rates of impairment and relative risk of impaired Processing Speed and Working Memory Index Scores from the WAIS–WMS III.

John DeLuca; Gordon J. Chelune; David S. Tulsky; Jean Lengenfelder; Nancy D. Chiaravalloti

2004-01-01

69

Memory and schizophrenia: differential link of processing speed and selective attention with two levels of encoding  

Microsoft Academic Search

The purpose of this study was to investigate how underlying cognitive deficits such as a defect in processing speed or in selective attention contributed to different types of memory impairment observed in schizophrenia (superficial vs deep encoding). 49 schizophrenic patients and 40 normal controls were administered a verbal memory task. Superficial encoding was assessed by the ability to recall items

Gildas Brébion; Mark J Smith; Jack M Gorman; Dolores Malaspina; Zafar Sharif; Xavier Amador

2000-01-01

70

Children's Arithmetical Difficulties: Contributions from Processing Speed, Item Identification, and Short-Term Memory  

Microsoft Academic Search

Children's arithmetical difficulties are often explained in terms of a short-term memory deficit. However, the underlying cause of this memory deficit is unclear, with some researchers suggesting a slow articulation rate and hence increased decay of information during recall, while others offer an explanation in terms of slow speed of item identification, indicating difficulty in retrieving information stored in long-term

Rebecca Bull; Rhona S. Johnston

1997-01-01

71

Marijuana effects on the speed of memory retrieval in the letter-matching task.  

PubMed

Marijuana's effect on the speed of retrieving simple information from memory was studied using a task in which subjects saw two letters and decided whether or not they had the same name. Subjects smoked a single marijuana or placebo cigarette under double-blind conditions. Marijuana slowed reaction time relative to placebo, but this effect was not influenced by the demands on memory retrieval or by providing advance information relevant to the required decisions, suggesting that memory retrieval was unimpaired. PMID:3486840

Block, R I; Wittenborn, J R

1986-02-01

72

Do working memory-driven attention shifts speed up visual awareness?  

Microsoft Academic Search

Previous research has shown that content representations in working memory (WM) can bias attention in favor of matching stimuli\\u000a in the scene. Using a visual prior-entry procedure, we here investigate whether such WM-driven attention shifts can speed\\u000a up the conscious awareness of memory-matching relative to memory-mismatching stimuli. Participants were asked to hold a color\\u000a cue in WM and to subsequently

Yi Pan; Qiu-Ping Cheng

73

Predictors of Memory and Processing Speed Dysfunctions after Traumatic Brain Injury  

PubMed Central

Background. The aims of this study were to evaluate the predictive value of admission Glasgow Coma Scale (GCS) scores, duration of unconsciousness, neurosurgical intervention, and countercoup lesion on the impairment of memory and processing speed functions six months after a traumatic brain injury (TBI) based on a structural equation modeling. Methods. Thirty TBI patients recruited from Neurosurgical Department at the Kaohsiung Medical University Hospital were administered the Wechsler Memory Scale-III (WMS-III) and the Wechsler Adult Intelligence Scale-III processing speed index to evaluate the memory and processing speed functions. Results. The study showed that GCS scores accounted for 40% of the variance in memory/processing speed. No significant predictive effects were found for the other three variables. GCS classification at the time of TBI seems to correspond moderately to the severity of memory/processing speed dysfunctions. Conclusions. The present study demonstrated that admission GCS score is a robust predictor of memory/processing speed dysfunctions after TBI. The results should be replicated with a large sample of patients with TBI, or be extended by examining other potential clinical predictors. PMID:24877054

Winardi, William; Kwan, Aij-Lie; Wang, Tse-Lun; Su, Yu-Feng; Yen, Chun-Po; Tsai, Hung-Pei; Sheehan, Jason; Su, Chwen-Yng

2014-01-01

74

Enabling Universal Memory by Overcoming the Contradictory Speed and Stability Nature of Phase-Change Materials  

NASA Astrophysics Data System (ADS)

The quest for universal memory is driving the rapid development of memories with superior all-round capabilities in non-volatility, high speed, high endurance and low power. Phase-change materials are highly promising in this respect. However, their contradictory speed and stability properties present a key challenge towards this ambition. We reveal that as the device size decreases, the phase-change mechanism changes from the material inherent crystallization mechanism (either nucleation- or growth-dominated), to the hetero-crystallization mechanism, which resulted in a significant increase in PCRAM speeds. Reducing the grain size can further increase the speed of phase-change. Such grain size effect on speed becomes increasingly significant at smaller device sizes. Together with the nano-thermal and electrical effects, fast phase-change, good stability and high endurance can be achieved. These findings lead to a feasible solution to achieve a universal memory.

Wang, Weijie; Loke, Desmond; Shi, Luping; Zhao, Rong; Yang, Hongxin; Law, Leong-Tat; Ng, Lung-Tat; Lim, Kian-Guan; Yeo, Yee-Chia; Chong, Tow-Chong; Lacaita, Andrea L.

2012-04-01

75

The Effects of Alcohol on the Speed of Memory Retrieval.  

ERIC Educational Resources Information Center

Recent research has clearly indicated that intoxication with alcohol impairs memory. The present study investigated the effects of alcohol on retrieval from long-term memory by using a set of cognitive decision tasks. Subjects (N=24) were female college students in good health not taking oral contraceptives. Subjects were administered 0 or 1.0…

Stempel, Jennifer J.; And Others

76

High speed optical object recognition processor with massive holographic memory  

NASA Technical Reports Server (NTRS)

Real-time object recognition using a compact grayscale optical correlator will be introduced. A holographic memory module for storing a large bank of optimum correlation filters, to accommodate the large data throughput rate needed for many real-world applications, has also been developed. System architecture of the optical processor and the holographic memory will be presented. Application examples of this object recognition technology will also be demonstrated.

Chao, T.; Zhou, H.; Reyes, G.

2002-01-01

77

Working memory influences processing speed and reading fluency in ADHD  

Microsoft Academic Search

Processing-speed deficits affect reading efficiency, even among individuals who recognize and decode words accurately. Children with ADHD who decode words accurately can still have inefficient reading fluency, leading to a bottleneck in other cognitive processes. This “slowing” in ADHD is associated with deficits in fundamental components of executive function underlying processing speed, including response selection. The purpose of the present

Lisa A. Jacobson; Matthew Ryan; Rebecca B. Martin; Joshua Ewen; Stewart H. Mostofsky; Martha B. Denckla; E. Mark Mahone

2011-01-01

78

Societal Implicit Memory and his Speed on Tracking Extrema in ...  

E-print Network

environmental upgrade frequencies, landscape changing speed severity, type of .... taken into account in the optimization process, we call the problem dynamic ...... In here, X and Y axis represent the index of the sample points in parameters ...

Vitorino Ramos

2005-11-22

79

Scalable, memory efficient, high-speed IP lookup algorithms  

Microsoft Academic Search

One of the central issues in router performance is IP address lookup based on longest prefix matching. IP address lookup algorithms can be evaluated on a number of metrics--lookup time, update time, memory usage, and to a less important extent, the time to construct the data structure used to support lookups and updates. Many of the existing methods are geared

Rama Sangireddy; Natsuhiko Futamura; Srinivas Aluru; Arun K. Somani

2005-01-01

80

Intelligence and the Effects of Perceptual Processing Demands, Task Difficulty, and Processing Speed on P300, Reaction Time and Movement Time.  

ERIC Educational Resources Information Center

The latency and amplitude of the P300, an event-related potential, during the performance of a memory-scanning task were used as indices of the efficiency of information processing that may mediate individual differences in intelligence. Results with 61 female college students contradict a pure speed of processing explanation of the relationship…

Houlihan, Michael; Stelmack, Robert; Campbell, Kenneth

1998-01-01

81

A Novel High-Speed Memory Organization for Fine-Grain Multi-Thread Computing  

Microsoft Academic Search

In this paper, we propose a novel organization of high-speed memories, known as the register-cache, for a multi-threaded architecture. As the term suggests, it is organized both as a register file and a cache. Viewed from the execution unit, its contents are addressable similar to ordinary CPU registers using relatively short addresses. From the main memory perspective, it is content

Herbert H. J. Hum; Guang R. Gao

1991-01-01

82

The relationship between IQ, memory, executive function, and processing speed in recent-onset psychosis: 1-year stability and clinical outcome.  

PubMed

Studies commonly report poor performance in psychotic patients compared with controls on tasks testing a range of cognitive functions, but, because current IQ is often not matched between these groups, it is difficult to determine whether this represents a generalized deficit or specific abnormalities. Fifty-three first-episode psychosis patients and 53 healthy controls, one-to-one matched for sex, age, and full-scale current IQ, were compared on Wechsler Adult Intelligence Scale (WAIS) subtests representing indices of perceptual organization, verbal comprehension, processing speed, and working memory as well as other tests of executive function and episodic memory. The groups showed an equivalent pattern of performance on all WAIS subtests except digit symbol processing speed, on which the patients were significantly worse. Patients were also worse on measures where performance correlated with digit symbol score, namely working and verbal memory tasks. Standardized residual scores for each subtest were calculated for each patient using the difference between their actual subtest score and a predicted subtest score based on their full-scale IQ and the performance of controls. Scaled scores and residual scores were examined for relationships with clinical measures. Digit symbol-scaled score was significantly correlated with concurrent negative syndrome score at baseline, and digit symbol residual score significantly predicted residual negative symptoms at 1-year follow-up. In summary, our comparison of patients and controls precisely matched for IQ revealed that processing speed was attenuated in recent-onset schizophrenia, contributed significantly to working and episodic memory deficits, and was a prognostic factor for poor outcome at 1 year. PMID:18682375

Leeson, Verity C; Barnes, Thomas R E; Harrison, Masuma; Matheson, Elizabeth; Harrison, Isobel; Mutsatsa, Stanley H; Ron, Maria A; Joyce, Eileen M

2010-03-01

83

The Relationship Between IQ, Memory, Executive Function, and Processing Speed in Recent-Onset Psychosis: 1-Year Stability and Clinical Outcome  

PubMed Central

Studies commonly report poor performance in psychotic patients compared with controls on tasks testing a range of cognitive functions, but, because current IQ is often not matched between these groups, it is difficult to determine whether this represents a generalized deficit or specific abnormalities. Fifty-three first-episode psychosis patients and 53 healthy controls, one-to-one matched for sex, age, and full-scale current IQ, were compared on Wechsler Adult Intelligence Scale (WAIS) subtests representing indices of perceptual organization, verbal comprehension, processing speed, and working memory as well as other tests of executive function and episodic memory. The groups showed an equivalent pattern of performance on all WAIS subtests except digit symbol processing speed, on which the patients were significantly worse. Patients were also worse on measures where performance correlated with digit symbol score, namely working and verbal memory tasks. Standardized residual scores for each subtest were calculated for each patient using the difference between their actual subtest score and a predicted subtest score based on their full-scale IQ and the performance of controls. Scaled scores and residual scores were examined for relationships with clinical measures. Digit symbol–scaled score was significantly correlated with concurrent negative syndrome score at baseline, and digit symbol residual score significantly predicted residual negative symptoms at 1-year follow-up. In summary, our comparison of patients and controls precisely matched for IQ revealed that processing speed was attenuated in recent-onset schizophrenia, contributed significantly to working and episodic memory deficits, and was a prognostic factor for poor outcome at 1 year. PMID:18682375

Leeson, Verity C.; Barnes, Thomas R. E.; Harrison, Masuma; Matheson, Elizabeth; Harrison, Isobel; Mutsatsa, Stanley H.; Ron, Maria A.; Joyce, Eileen M.

2010-01-01

84

Nonideal battery and main memory effects on CPU speed-setting for low power  

Microsoft Academic Search

This paper explores the system-level power-performance tradeoffs of dynamically varying CPU speed. Previous work in CPU speed-setting considered only the power of the CPU and only CPUs that vary supply voltage with frequency. This work takes a broader approach, considering total system power, battery capacity, and main memory bandwidth. The results, which are up to a factor of four less

Thomas L. Martin; Daniel P. Siewiorek

2001-01-01

85

High-Speed Behavior of Some Shape Memory Alloys  

SciTech Connect

The results of dynamic tests of shape memory alloys Ti-Ni and Cu-Al-Ni are given. Compressive tests of Ti-Ni alloy were carried out at temperatures 293-573K. Considerable influence of temperature on module of elasticity prior to the dislocation plastic flow and dislocation yield limit has been mentioned in temperature interval of reverse martensitic transformation. For Cu-Al-Ni alloy a strain rate influence on phase yield limit, module of elasticity prior to the phase unelastic flow, module of elasticity prior to the dislocation plastic flow was negligible. The method of determination of duration of reverse martensitic transformation has been realized by the example of Cu-Al-Ni alloy.

Bragov, Anatoly M.; Lomunov, Andrey K.; Sergeichev, Ivan V. [Research Institute of Mechanics, Nizhny Novgorod State University, GSP-1000 (Russian Federation)

2006-07-28

86

Executive Functioning in Schizophrenia: The Contributions of Attention, Working Memory, Processing Speed, and General Intelligence  

Microsoft Academic Search

The purpose of this study was to assess the degree to which executive functioning performance may be associated with indices of attention, working memory, processing speed, and general in- telligence in 45 individuals with schizophrenia from a multicultural sample. It was hypothesized that relatively higher performances on measures of these cognitive processes would be positively associated with higher executive functioning

Cale D. Palmer; Elaine Heiby; Velma Kameoka

2008-01-01

87

Associative Learning Predicts Intelligence above and beyond Working Memory and Processing Speed  

ERIC Educational Resources Information Center

Recent evidence suggests the existence of multiple cognitive mechanisms that support the general cognitive ability factor (g). Working memory and processing speed are the two best established candidate mechanisms. Relatively little attention has been given to the possibility that associative learning is an additional mechanism contributing to g.…

Kaufman, Scott Barry; DeYoung, Colin G; Gray, Jeremy R.; Brown, Jamie; Mackintosh, Nicholas

2009-01-01

88

Perceptual-Gestural (Mis)Mapping in Serial Short-Term Memory: The Impact of Talker Variability  

ERIC Educational Resources Information Center

The mechanisms underlying the poorer serial recall of talker-variable lists (e.g., alternating female-male voices) as compared with single-voice lists were examined. We tested the novel hypothesis that this "talker variability effect" arises from the tendency for perceptual organization to partition the list into streams based on voice such that…

Hughes, Robert W.; Marsh, John E.; Jones, Dylan M.

2009-01-01

89

Dissociable mechanisms of speed-accuracy tradeoff during visual perceptual learning are revealed by a hierarchical drift-diffusion model  

PubMed Central

Two phenomena are commonly observed in decision-making. First, there is a speed-accuracy tradeoff (SAT) such that decisions are slower and more accurate when instructions emphasize accuracy over speed, and vice versa. Second, decision performance improves with practice, as a task is learnt. The SAT and learning effects have been explained under a well-established evidence-accumulation framework for decision-making, which suggests that evidence supporting each choice is accumulated over time, and a decision is committed to when the accumulated evidence reaches a decision boundary. This framework suggests that changing the decision boundary creates the tradeoff between decision speed and accuracy, while increasing the rate of accumulation leads to more accurate and faster decisions after learning. However, recent studies challenged the view that SAT and learning are associated with changes in distinct, single decision parameters. Further, the influence of speed-accuracy instructions over the course of learning remains largely unknown. Here, we used a hierarchical drift-diffusion model to examine the SAT during learning of a coherent motion discrimination task across multiple training sessions, and a transfer test session. The influence of speed-accuracy instructions was robust over training and generalized across untrained stimulus features. Emphasizing decision accuracy rather than speed was associated with increased boundary separation, drift rate and non-decision time at the beginning of training. However, after training, an emphasis on decision accuracy was only associated with increased boundary separation. In addition, faster and more accurate decisions after learning were due to a gradual decrease in boundary separation and an increase in drift rate. The results suggest that speed-accuracy instructions and learning differentially shape decision-making processes at different time scales. PMID:24782701

Zhang, Jiaxiang; Rowe, James B.

2014-01-01

90

Programming future architectures : dusty decks, memory walls, and the speed of light.  

SciTech Connect

Due to advances in CMOS fabrication technology, high performance computing capabilities have continually grown. More capable hardware has allowed a range of complex scientific applications to be developed. However, these applications present a bottleneck to future performance. Entrenched 'legacy' codes - 'Dusty Decks' - demand that new hardware must remain compatible with existing software. Additionally, conventional architectures faces increasing challenges. Many of these challenges revolve around the growing disparity between processor and memory speed - the 'Memory Wall' - and difficulties scaling to large numbers of parallel processors. To a large extent, these limitations are inherent to the traditional computer architecture. As data is consumed more quickly, moving that data to the point of computation becomes more difficult. Barring any upward revision in the speed of light, this will continue to be a fundamental limitation on the speed of computation. This work focuses on these solving these problems in the context of Light Weight Processing (LWP). LWP is an innovative technique which combines Processing-In-Memory, short vector computation, multithreading, and extended memory semantics. It applies these techniques to try and answer the questions 'What will a next-generation supercomputer look like?' and 'How will we program it?' To that end, this work presents four contributions: (1) An implementation of MPI which uses features of LWP to substantially improve message processing throughput; (2) A technique leveraging extended memory semantics to improve message passing by overlapping computation and communication; (3) An OpenMP library modified to allow efficient partitioning of threads between a conventional CPU and LWPs - greatly improving cost/performance; and (4) An algorithm to extract very small 'threadlets' which can overcome the inherent disadvantages of a simple processor pipeline.

Rodrigues, Arun F.

2005-08-01

91

Assessing the validity of computer-game-like tests of processing speed and working memory  

Microsoft Academic Search

Processing speed (Gs) and working memory (WM) tasks have received considerable interest as correlates of more complex cognitive\\u000a performance measures. Gs and WM tasks are often repetitive and are often rigidly presented, however. The effects of Gs and\\u000a WM may, therefore, be confounded with those of motivation and anxiety. In an effort to address this problem, we assessed the\\u000a concurrent

Jason McPherson; Nicholas R. Burns

2008-01-01

92

Relationships Among Linguistic Processing Speed, Phonological Working Memory, and Attention in Children Who Stutter  

PubMed Central

Relatively recently, experimental studies of linguistic processing speed in children who stutter (CWS) have emerged, some of which suggest differences in performance among CWS compared to children who do not stutter (CWNS). What is not yet well understood is the extent to which underlying cognitive skills may impact performance on timed tasks of linguistic performance. The purpose of this study was to explore possible relationships between measures of linguistic processing speed and two aspects of cognition: phonological working memory and attention. Participants were 9 CWS and 14 CWNS between the ages of 3;6 and 5;2. Children participated in a computerized picture naming task (an index of linguistic processing speed) and a nonword repetition task (an index of phonological working memory). Parents completed a temperament behavior questionnaire, from which information about the children’s attentional skills was collected. Findings revealed that the groups did not differ from each other on speed of picture naming or attention; however, the CWS performed significantly worse in nonword repetition. In addition, after partialling out the effects of age, (a) for CWS only, there was a significant negative relationship between picture naming speed and nonword repetition; (b) there were no significant relationships for either group between aspects of attention and picture naming speed; and (c) only the CWNS showed a significant relationship between nonword repetition and focused attentional skills. These results underscore the need to consider the underlying skills associated with lexically-related aspects of language production when examining the task performances of CWS and CWNS. PMID:20831969

Anderson, Julie D.; Wagovich, Stacy A.

2010-01-01

93

VLSI architecture of low memory and high speed 2D lifting-based discrete wavelet transform for JPEG2000 applications  

Microsoft Academic Search

The paper presents a low memory and high speed VLSI architecture for 2D lifting-based lossless 5\\/3 filter discrete wavelet transform (DWT). The architecture is based on the proposed interlaced read scan algorithm (IRSA) and parallel scheme processing to achieve low memory size and high speed operation. The proposed lifting-based DWT architecture has the advantages of lower computational complexity, transforming signal

Jen-shiun Chiang; Chih-hsien Hsia; Hsin-jung Chen; Te-jung Lo

2005-01-01

94

A New Method for High-Speed Dynamic TSPC Memory by Low-Temperature Poly Silicon TFT Technology  

Microsoft Academic Search

We propose an 8 by 8 dynamic true-single-phase-clock (TSPC) circuit based on low-temperature polycrystalline silicon (LTPS) technology to perform high speed dynamic memory cell. The proposed method allows the memory access rate to reach 25 MHz, in contrast to the traditional LTPS memory, with static circuit design, that operates at a low frequency of only about 6 MHZ. The 8

Yu-Cheng Fan; Ta-Che Lo

2009-01-01

95

Cycles in Speed-Working Memory-G Relations: Towards a Developmental-Differential Theory of the Mind  

ERIC Educational Resources Information Center

This article presents three studies, two of them longitudinal, which investigated the relations between age, processing speed, working memory (WM), and fluid intelligence ("g[subscript f]") from 4 to 16 years of age. Structural equation modeling showed that speed was a powerful covariate of age ([approximately] - 0.6 to - 0.7) from 4 to 13 years,…

Demetriou, Andreas; Spanoudis, George; Shayer, Michael; Mouyi, Antigoni; Kazi, Smaragda; Platsidou, Maria

2013-01-01

96

Menstrual Cycle Effects on Perceptual Closure Mediate Changes in Performance on a Fragmented Objects Test of Implicit Memory  

ERIC Educational Resources Information Center

Healthy premenopausal women with regular menstrual cycles were assessed on a fragmented objects test of implicit memory. Testing took place at either the low estrogen (n=17) or the high estrogen (n=16) stages of the menstrual cycle. Concentrations of ovarian hormones were confirmed by saliva assays. Both groups of women exhibited a priming effect,…

Hampson, E.; Finestone, J.M.; Levy, N.

2005-01-01

97

An ASIC memory buffer controller for a high speed disk system  

NASA Technical Reports Server (NTRS)

The need for large capacity, high speed mass memory storage devices has become increasingly evident at NASA during the past decade. High performance mass storage systems are crucial to present and future NASA systems. Spaceborne data storage system requirements have grown in response to the increasing amounts of data generated and processed by orbiting scientific experiments. Predictions indicate increases in the volume of data by orders of magnitude during the next decade. Current predictions are for storage capacities on the order of terabits (Tb), with data rates exceeding one gigabit per second (Gbps). As part of the design effort for a state of the art mass storage system, NASA Langley has designed a 144 CMOS ASIC to support high speed data transfers. This paper discusses the system architecture, ASIC design and some of the lessons learned in the development process.

Hodson, Robert F.; Campbell, Steve

1993-01-01

98

High-speed 1280x1024 camera with 12-Gbyte SDRAM memory  

NASA Astrophysics Data System (ADS)

A 600 Frame/s camera based on 1.3 Megapixel CMOS sensor (PBMV13) with wide digital data output bus (10 parallel outputs of 10 bit worlds) was developed using high capacity SCRAM memory. This architecture allows to achieve 10 seconds of continuous recording of digital data from the sensor at 600 frames per second to the memory box with up to 12 1Gbytes SDRAM modules. Acquired data is transmitted through the fibre optic channel connected to the camera via FPDP interface to a PC type computer at the speed of 100 Mbyte per second and fibre cable length up to 10 km. All camera settings such as shutter time, frame rate, image size, present for changing integration time and frame rate, can be controlled by software. Camera specifications: shutter time - from 3.3 us to full frame at 1.6 us steps at 600 fps and then 1 frame steps down to 16 ms, frame rate - from 60 fps to 600 fps, image size 1280x1024, 1280x512, 1290x256, or 1280x128, changing on a fly - presetting two step table, memory capacity - depends on frame size (6000 frames with 1280x1024 or 48000 frames with 1280x128 resolution). Program can work with monochrome or color versions of the MV13 sensor.

Postnikov, Konstantin O.; Yakovlev, Alexey V.

2001-04-01

99

Perceptual-Cognitive Expertise in Elite Volleyball Players  

PubMed Central

The goal of the current study was to investigate the relationship between sport expertise and perceptual and cognitive skills, as measured by the component skills approach. We hypothesized that athletes would outperform non-athlete controls in a number of perceptual and cognitive domains and that sport expertise would minimize gender differences. A total of 154 individuals (87 professional volleyball players and 67 non-athlete controls) participated in the study. Participants performed a cognitive battery, which included tests of executive control, memory, and visuo-spatial attention. Athletes showed superior performance speed on three tasks (two executive control tasks and one visuo-spatial attentional processing task). In a subset of tasks, gender effects were observed mainly in the control group, supporting the notion that athletic experience can reduce traditional gender effects. The expertise effects obtained substantiate the view that laboratory tests of cognition may indeed enlighten the sport-cognition relationship. PMID:23471100

Alves, Heloisa; Voss, Michelle W.; Boot, Walter R.; Deslandes, Andrea; Cossich, Victor; Salles, Jose Inacio; Kramer, Arthur F.

2013-01-01

100

Predicting Episodic Memory Performance of Very Old Men and Women: Contributions From Age, Depression, Activity, Cognitive Ability, and Speed  

Microsoft Academic Search

Regression models were developed to explain age-related and total variance in memory and to determine the independent contribution from general processing speed, having taken into account cognitive and noncognitive individual differences. Episodic memory was assessed for 3 tasks in a population-based sample of 951 adults comprising 515 men and 436 women (aged 70–96, M = 77.6, SD = 5.5). Correlations

Mary A. Luszcz; Janet Bryan; Patricia Kent

1997-01-01

101

No Implicit Memory for Stories Played during Isoflurane\\/Alfentanil\\/Nitrous Oxide Anesthesia: A Reading Speed Measurement  

Microsoft Academic Search

Implicit memory of intraoperatively presented stories was recently detected by using the reading speed para- digm during propofol-alfentanil-nitrous oxide anesthe- sia. Our main goal was to evaluate the reading speed test procedure under another anesthetic regimen, i.e., isoflurane combined with nitrous oxide and alfentanil- infusion. In both experiments, patients were premedi- cated with oral midazolam. In a previous experiment, patients

Martin Leuwer; Bernd Mitzlaff; Sami Hussein; Siegfried A. Piepenbrock

2000-01-01

102

Mediators of long-term memory performance across the life span  

Microsoft Academic Search

An individual-differences approach was used to examine the component processes that predict epi- sodic long-term memory performance. A total of 301 participants ages 20-90 received a 7-hr cogni- tive battery across 3 days. Key constructs hypothesized to affect long-term memory function were assessed, including multiple measures of working memory and perceptual speed. Latent-construct, structural equation modeling was used to examine

Denise C. Park; Anderson D. Smith; Gary Lautenschlager; Julie L. Earles

1996-01-01

103

Individual differences and predictors of forgetting in old age: The role of processing speed and working memory  

Microsoft Academic Search

The goal of the present study was to examine whether individual differences in basic cognitive abilities, processing speed, and working memory, are reliable predictors of individual differences in forgetting rates in old age. The sample for the present study comprised 364 participants aged between 65 and 80 years from the Zurich Longitudinal Study on Cognitive Aging. The impact of basic

Daniel Zimprich; Tanja Kurtz

2012-01-01

104

Information processing speed, neural efficiency, and working memory performance in multiple sclerosis: Differential relationships with structural magnetic resonance imaging  

Microsoft Academic Search

Multiple sclerosis (MS), a central nervous system (CNS) neurodegenerative disorder, involves lesions of both white and gray matter and reported cognitive impairments that include processing speed (PS), executive function, and working memory (WM). This study closely examined the specifics of these cognitive deficits and their relationship to structural brain damage. A visual n-back task with 3 WM load conditions was

Thomas J. Covey; Robert Zivadinov; Janet L. Shucard; David W. Shucard

2011-01-01

105

Acute, intermediate intensity exercise, and speed and accuracy in working memory tasks: A meta-analytical comparison of effects  

Microsoft Academic Search

The purpose of this study was to compare, using meta-analytic techniques, the effect of acute, intermediate intensity exercise on the speed and accuracy of performance of working memory tasks. It was hypothesized that acute, intermediate intensity exercise would have a significant beneficial effect on response time and that effect sizes for response time and accuracy data would differ significantly. Random-effects

Terry McMorris; John Sproule; Anthony Turner; Beverley J. Hale

2011-01-01

106

Architectural Support for High Speed Protection of Memory Integrity and Confidentiality in Multiprocessor Systems  

E-print Network

of Electrical and Computer Engineering Georgia Institute of Technology Atlanta, GA 30332-0280 {shiw, memory is often shared by multiple processing elements that support a shared system memory with a snooping cache coherence protocol. Authen- ticating shared memory is a new challenge to memory pro- tection

Lee, Hsien-Hsin "Sean"

107

Working Memory and Arithmetic Calculation in Children: The Contributory Roles of Processing Speed, Short-Term Memory, and Reading  

ERIC Educational Resources Information Center

The cognitive underpinnings of arithmetic calculation in children are noted to involve working memory; however, cognitive processes related to arithmetic calculation and working memory suggest that this relationship is more complex than stated previously. The purpose of this investigation was to examine the relative contributions of processing…

Berg, Derek H.

2008-01-01

108

High-speed and localized resistive switching characteristics of double-layer SrZrO3 memory devices  

NASA Astrophysics Data System (ADS)

The fabrication of SrZrO3 (SZO) memory devices with oxygen-rich (OR) and oxygen-deficient (OD) double layers, their resistive switching (RS) characteristics and mechanisms are investigated in this study. Due to the difference in oxygen content between the OR and OD layers formed by an oxygen flow control (OFC) process during SZO deposition, the RS region is effectively reduced and localized within the OR layer, which leads to a low operation voltage and stable RS behaviours. Furthermore, the OFC SZO device exhibits high-speed switching (10 ns) over 400 times and long retention (>106 s), showing promising potential for next-generation nonvolatile memory applications.

Lin, Meng-Han; Wu, Ming-Chi; Huang, Chun-Yang; Lin, Chen-Hsi; Tseng, Tseung-Yuen

2010-07-01

109

Stochastic accumulation of feature information in perception and memory  

PubMed Central

It is now well established that the time course of perceptual processing influences the first second or so of performance in a wide variety of cognitive tasks. Over the last 20 years, there has been a shift from modeling the speed at which a display is processed, to modeling the speed at which different features of the display are perceived and formalizing how this perceptual information is used in decision making. The first of these models (Lamberts, 1995) was implemented to fit the time course of performance in a speeded perceptual categorization task and assumed a simple stochastic accumulation of feature information. Subsequently, similar approaches have been used to model performance in a range of cognitive tasks including identification, absolute identification, perceptual matching, recognition, visual search, and word processing, again assuming a simple stochastic accumulation of feature information from both the stimulus and representations held in memory. These models are typically fit to data from signal-to-respond experiments whereby the effects of stimulus exposure duration on performance are examined, but response times (RTs) and RT distributions have also been modeled. In this article, we review this approach and explore the insights it has provided about the interplay between perceptual processing, memory retrieval, and decision making in a variety of tasks. In so doing, we highlight how such approaches can continue to usefully contribute to our understanding of cognition. PMID:24860530

Kent, Christopher; Guest, Duncan; Adelman, James S.; Lamberts, Koen

2014-01-01

110

Assessing the validity of computer-game-like tests of processing speed and working memory.  

PubMed

Processing speed (Gs) and working memory (WM) tasks have received considerable interest as correlates of more complex cognitive performance measures. Gs and WM tasks are often repetitive and are often rigidly presented, however. The effects of Gs and WM may, therefore, be confounded with those of motivation and anxiety. In an effort to address this problem, we assessed the concurrent and predictive validity of computer-game-like tests of Gs (Space Code) and WM (Space Matrix) across two experiments. In Experiment 1, within a university sample (N = 70), Space Matrix exhibited concurrent validity as a WM measure, whereas Space Code appeared to be a mixed-ability measure. In Experiment 2, Space Matrix exhibited concurrent validity as well as predictive validity (as a predictor of school grades) within a school-aged sample (N = 94), but the results for Space Code were less encouraging. Relationships between computer-game-like tests and gender, handedness, and computer-game experience are also discussed. PMID:19001388

McPherson, Jason; Burns, Nicholas R

2008-11-01

111

Local consumption speed of turbulent premixed flames - An analysis of ''memory effects''  

SciTech Connect

The local turbulent flame speed of an attached flame is not only a function of the local flow and flame conditions, but also of upstream conditions - i.e., it is ''non-local'' or exhibits ''memory''. Non-locality adds an additional degree of freedom to the classic problem of a freely propagating flame propagating normally to the time averaged flow. Non-locality occurs due to mean tangential flow along the flame brush, which causes flame wrinkles to translate downstream. As such, the wrinkling of the flame at any given point is not only a function of the local velocity disturbance, but also a superposition of flame surface perturbations from locations upstream at previous times. This causes the correlation length scale of turbulent flame wrinkles to differ from that of the underlying turbulent velocity fluctuations. The objective of this paper is to provide a physical description of the key flame kinematic processes that cause these non-local effects. Two approaches are adopted in this work. First, analytical solutions of the G-equation that explicitly describe the effect of non-locality in the low turbulence limit are developed. Second, numerical computations of the G-equation are performed that demonstrate the role of non-linearity in flame surface kinematics at higher turbulence intensities. Finally, these predictions are shown to be consistent with data from a turbulent Bunsen flame. (author)

Hemchandra, Santosh; Lieuwen, Tim [School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

2010-05-15

112

Visual prediction and perceptual expertise  

PubMed Central

Making accurate predictions about what may happen in the environment requires analogies between perceptual input and associations in memory. These elements of predictions are based on cortical representations, but little is known about how these processes can be enhanced by experience and training. On the other hand, studies on perceptual expertise have revealed that the acquisition of expertise leads to strengthened associative processing among features or objects, suggesting that predictions and expertise may be tightly connected. Here we review the behavioral and neural findings regarding the mechanisms involving prediction and expert processing, and highlight important possible overlaps between them. Future investigation should examine the relations among perception, memory and prediction skills as a function of expertise. The knowledge gained by this line of research will have implications for visual cognition research, and will advance our understanding of how the human brain can improve its ability to predict by learning from experience. PMID:22123523

Cheung, Olivia S.; Bar, Moshe

2012-01-01

113

Individual Differences in Executive Processing Predict Susceptibility to Interference in Verbal Working Memory  

Microsoft Academic Search

Recent theories have suggested that resistance to interference is a unifying principle of executive function and that individual differences in interference may be explained by executive function (M. J. Kane & R. W. Engle, 2002). Measures of executive function, memory, and perceptual speed were obtained from 121 older adults (ages 63–82). We used structural equation modeling to investigate the relationships

Trey Hedden; Carolyn Yoon

2006-01-01

114

Aging White Matter and Cognition: Differential Effects of Regional Variations in Diffusion Properties on Memory, Executive Functions, and Speed  

PubMed Central

Disruption of cerebral white matter has been proposed as an explanation for age-related cognitive declines. However, the role of specific regions in specific cognitive declines remains unclear. We used diffusion tensor imaging to examine the associations between regional microstructural integrity of the white matter and performance on age-sensitive cognitive tasks in a sample of healthy adults (N = 52, age 19–81 years). White matter integrity was assessed by fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in multiple regions of interest (genu and splenium of corpus callosum, internal capsule limbs, prefrontal, temporal, superior/posterior parietal, occipital white matter) and related to processing speed, working memory, inhibition, task switching, and episodic memory. We found that age and regional white matter integrity differentially influenced cognitive performance. Age-related degradation in anterior brain areas was associated with decreased processing speed and poorer working memory, whereas reduced inhibition and greater task switching costs were linked to decline in posterior areas. Poorer episodic memory was associated with age-related differences in central white matter regions. The observed multiple dissociations among specific age-sensitive cognitive skills and their putative neuroanatomical substrates support the view that age-related cognitive declines are unlikely to stem from a single cause. PMID:19166865

Kennedy, Kristen M.; Raz, Naftali

2009-01-01

115

Polymorphisms in the Brain-Derived Neurotrophic Factor Gene Influence Memory and Processing Speed One Month after Brain Injury  

PubMed Central

Abstract Brain-derived neurotrophic factor (BDNF) plays a role in cognition, as well as neural survival and plasticity. There are several common polymorphisms in the BDNF gene, one of which (rs6265) is an extensively studied non-synonymous coding polymorphism (Val66Met) which has been linked to cognitive performance in healthy controls and some clinical populations. We hypothesized that the Met allele of rs6265 would be associated with poorer cognitive performance in individuals with mild-to-moderate traumatic brain injury, and that other polymorphisms in the BDNF gene would also affect cognition. Genotype at 9 single-nucleotide polymorphisms (SNPs) in the BDNF gene, and measures of speed of information processing, learning, and memory were assessed in 75 patients with mTBI and 38 healthy subjects. Consistent with previous reports, the Met allele of rs6265 was associated with cognition (slower processing speed) in the entire group. Two other SNPs were associated with processing speed in the mTBI group, but both are in linkage disequilibrium with rs6265, and neither remained significant after adjustment for rs6265 status. Within the mTBI group, but not the controls, 4 SNPs, but not rs6265, were associated with memory measures. These associations were not affected by adjustment for rs6265 status. Polymorphisms in BDNF influence cognitive performance shortly after mTBI. The results raise the possibility that a functional polymorphism other than rs6265 may contribute to memory function after mTBI. PMID:22188054

Tyler, Anna L.; Flashman, Laura A.; Rhodes, C. Harker; McDonald, Brenna C.; Saykin, Andrew J.; Tosteson, Tor D.; Tsongalis, Gregory J.; Moore, Jason H.

2012-01-01

116

What does the WISC-III Measure? Comments on the Relationship between Intelligence, Working Memory Capacity, and Information Processing Speed and Efficiency  

Microsoft Academic Search

Keith and Witta’s (1997, this issue) results indicate that the standardization data of the Wechsler Intelligence Scale for Children-Third Edition (WISC-III, Wechsler, 1991) are best described by an hierarchical model with four first-order factors (viz., Verbal Comprehension, Perceptual Organization, Quantitative Reasoning, and Processing Speed) and one second-order general factor (i.e., psychometric g). Because their findings support the interpretation of the

John H. Kranzler

1997-01-01

117

Distinction between Perceptual and Attentional Processing in Working Memory Tasks: A Study of Phase-locked and Induced Oscillatory Brain Dynamics  

Microsoft Academic Search

Working memory involves the short-term storage and manipulation of information necessary for cognitive performance, including comprehension, learning, reasoning and planning. Although electroencephalogram (EEG) rhythms are modulated during working memory, the temporal relationship of EEG oscillations with the eliciting event has not been well studied. In particular, the dynamics of the neural network supporting memory processes may be best captured in

Marie-pierre Deiber; Pascal Missonnier; Olivier Bertrand; Gabriel Gold; Lara Fazio-costa; Vicente Ibañez; Panteleimon Giannakopoulos

2007-01-01

118

An exemplar-based random walk model of speeded classification  

Microsoft Academic Search

The authors propose and test an exemplar-based random walk model for predicting response times in tasks of speeded, multidimensional perceptual classification. The model combines elements of R.M. Nosofsky's (1986) generalized context model of categorization and G. D. Logan's (1988) instance-based model of automaticity. In the model, exemplars race among one another to be retrieved from memory, with rates determined by

Robert M. Nosofsky; Thomas J. Palmeri

1997-01-01

119

Perceptual asynchrony for motion  

PubMed Central

Psychophysical experiments show that two different visual attributes, color and motion, processed in different areas of the visual brain, are perceived at different times relative to each other (Moutoussis and Zeki, 1997a). Here we demonstrate psychophysically that two variants of the same attribute, motion, which have the same temporal structure and are processed in the same visual areas, are also processed asynchronously. When subjects were asked to pair up–down motion of dots in one half of their hemifield with up-right motion in the other, they perceived the two directions of motion asynchronously, with the advantage in favor of up-right motion; when they were asked to pair the motion of white dots moving against a black background with that of red dots moving against an equiluminant green background, they perceived the luminant motion first, thus demonstrating a perceptual advantage of luminant over equiluminant motion. These results were not affected by motion speed or perceived motion “streaks.” We thus interpret these results to reflect the different processing times produced by luminant and equiluminant motion stimuli or by different degrees of motion direction change, thus adding to the evidence that processing time within the visual system is a major determinant of perceptual time. PMID:24624071

Lo, Yu Tung; Zeki, Semir

2014-01-01

120

Speed and Accuracy of Accessing Information in Working Memory: An Individual Differences Investigation of Focus Switching  

ERIC Educational Resources Information Center

Three experiments examined the nature of individual differences in switching the focus of attention in working memory. Participants performed 3 versions of a continuous counting task that required successive updating and switching between counts. Across all 3 experiments, individual differences in working memory span and fluid intelligence were…

Unsworth, Nash; Engle, Randall W.

2008-01-01

121

High speed, very large (8 megabyte) first in/first out buffer memory (FIFO)  

DOEpatents

A fast FIFO (First In First Out) memory buffer capable of storing data at rates of 100 megabytes per second. The invention includes a data packer which concatenates small bit data words into large bit data words, a memory array having individual data storage addresses adapted to store the large bit data words, a data unpacker into which large bit data words from the array can be read and reconstructed into small bit data words, and a controller to control and keep track of the individual data storage addresses in the memory array into which data from the packer is being written and data to the unpacker is being read.

Baumbaugh, Alan E. (Batavia, IL); Knickerbocker, Kelly L. (Aurora, IL)

1989-01-01

122

Memory.  

ERIC Educational Resources Information Center

Discusses current research (including that involving amnesiacs and snails) into the nature of the memory process, differentiating between and providing examples of "fact" memory and "skill" memory. Suggests that three brain parts (thalamus, fornix, mammilary body) are involved in the memory process. (JN)

McKean, Kevin

1983-01-01

123

High-speed 1280x1024 camera with 12Gbyte SDRAM memory  

Microsoft Academic Search

A 600 Frame\\/s camera based on 1.3 Megapixel CMOS sensor (PBMV13) with wide digital data output bus (10 parallel outputs of 10 bit worlds) was developed using high capacity SCRAM memory. This architecture allows to achieve 10 seconds of continuous recording of digital data from the sensor at 600 frames per second to the memory box with up to 12

Konstantin O. Postnikov; Alexey V. Yakovlev

2001-01-01

124

High-Speed Memory Cell Circuit Design Based on Low-Temperature Poly Silicon TFT Technology  

Microsoft Academic Search

In this paper, low-temperature poly-silicon (LTPS) thin-film transistors (TFT) are used for LTPS memory on glass substrates. System on panel (SOP), combined with memory, controller, and driver circuits on a glass substrate, will be the most suitable applications for TFT panels in the near future. Recently, the low-temperature poly-silicon thin-film transistors prepared on glass substrates have been studied extensively. Compared

Yu-Cheng Fan; Yi-Cheng Liu

2009-01-01

125

Perceptual symbol systems  

Microsoft Academic Search

Prior to the twentieth century, theories of knowledge were inherently perceptual. Since then, developments in logic, statis- tics, and programming languages have inspired amodal theories that rest on principles fundamentally different from those underlying perception. In addition, perceptual approaches have become widely viewed as untenable because they are assumed to implement record- ing systems, not conceptual systems. A perceptual theory

Lawrence W. Barsalou

1999-01-01

126

The unattended speech effect: perception or memory?  

PubMed

Broadbent (1983) has suggested that the influence of unattended speech on immediate serial recall is a perceptual phenomenon rather than a memory phenomenon. In order to test this, subjects were required to classify visually presented pairs of consonants on the basis of either case or rhyme. They were tested both in silence and against a background of continuous spoken Arabic presented at 75 dB(A). No effect of unattended speech was observed on either the speed or accuracy of processing. A further study required subjects to decide whether visually presented nonwords were homophonous with real words. Again, performance was not impaired by unattended speech, although a clear effect was observed on an immediate serial memory task. Our results give no support to the perceptual interpretation of the unattended speech effect. PMID:2945899

Baddeley, A; Salamé, P

1986-10-01

127

Resistance to Interference of Olfactory Perceptual Learning  

ERIC Educational Resources Information Center

Olfactory memory is especially persistent. The current study explored whether this applies to a form of perceptual learning, in which experience of an odor mixture results in greater judged similarity between its elements. Experiment 1A contrasted 2 forms of interference procedure, "compound" (mixture AW, followed by presentation of new mixtures…

Stevenson, Richard J.; Case, Trevor I.; Tomiczek, Caroline

2007-01-01

128

Speeded Old-New Recognition of Multidimensional Perceptual Stimuli: Modeling Performance at the Individual-Participant and Individual-Item Levels  

ERIC Educational Resources Information Center

Observers made speeded old-new recognition judgments of color stimuli embedded in a multidimensional similarity space. The paradigm used multiple lists but with the underlying similarity structures repeated across lists, to allow for quantitative modeling of the data at the individual-participant and individual-item levels. Correct rejection…

Nosofsky, Robert M.; Stanton, Roger D.

2006-01-01

129

Cache Memories  

Microsoft Academic Search

Cache memories are used in modern, medium and high-speed CPUs to hold temporarily those portions of the contents of main memory which are {believed to be) currently in use. Since instructions and data in cache memories can usually be referenced in 10 to 25 percent of the time required to access main memory, cache memories permit the executmn rate of

Alan Jay Smith

1982-01-01

130

Relationships between time estimation, memory, attention, and processing speed in patients with severe traumatic brain injury  

Microsoft Academic Search

The present experiment was aimed at investigating the effects of memory and attention deficits and of information processing slowing on time estimation in patients with severe traumatic brain injury (TBI). Patients with TBI and normal control subjects reproduced and produced durations (5, 14, 38s) in both a control counting condition and in a concurrent reading condition. They also performed finger-tapping

Severine Perbal; Josette Couillet; Philippe Azouvi; Viviane Pouthas

2003-01-01

131

Scalable, memory efficient, high-speed lookup and update algorithms for IP routing  

Microsoft Academic Search

IP address lookup algorithms can be evaluated on a number of metrics lookup time, update time, memory usage, and to a lesser extent, the time to construct the data structure used to support lookups and updates. Many of the existing methods are geared towards optimizing a specific metric, and hence do not scale well with the ever expanding routing tables

Natsuhiko Futamura; Rama Sangireddy; Srinivas Aluru; Arun K. Somani

2003-01-01

132

A sex difference on a novel spatial working memory task in humans.  

PubMed

Neurophysiological and behavioral evidence suggests that the prefrontal cortex (PFC) may be sexually differentiated in nonhuman primates. The present study examined whether there are sex differences in working memory in humans that might reflect sexual differentiation of human PFC. Male and female undergraduates were administered a novel multitrial spatial working memory task (SPWM) and a verbal working memory task. In three experiments, females committed significantly fewer working memory errors and took significantly less time to reach criterion than males on the SPWM task. The female advantage was not accounted for by differences in general intellectual ability, attention, perceptual speed, incidental memory, or speed of verbal access. In Study 3, a sex difference was also observed on a measure of verbal working memory. The findings suggest that some prefrontal functions may be sexually differentiated in humans. PMID:11748902

Duff, S J; Hampson, E

2001-12-01

133

Information processing and reasoning with premises that are empirically false: Interference, working memory, and processing speed  

Microsoft Academic Search

In this study, we looked at the contributions of individual differences in susceptibility to interference and working memory\\u000a to logical reasoning with premises that were empirically false (i.e., not necessarily true). A total of 97 university students\\u000a were given a sentence completion task for which a subset of stimuli was designed to generate inappropriate semantic activation\\u000a that interfered with the

Henry markovits; Celine doyon

2004-01-01

134

Processing Speed and Visuospatial Executive Function Predict Visual Working Memory Ability in Older Adults  

Microsoft Academic Search

Background\\/Study Context: Visual working memory (VWM) has been shown to be particularly age sensitive. Determining which measures share variance with this cognitive ability in older adults may help to elucidate the key factors underlying the effects of aging.Methods: Predictors of VWM (measured by a modified Visual Patterns Test) were investigated in a subsample (N = 44, mean age = 73) of older adults from

Louise A. Brown; James R. Brockmole; Alan J. Gow; Ian J. Deary

2012-01-01

135

MgO-Based Tunnel Junction Material for High-Speed Toggle Magnetic Random Access Memory  

Microsoft Academic Search

We report the first demonstration of a magnetoresistive random access memory (MRAM) circuit incorporating MgO-based magnetic tunnel junction (MTJ) material for higher performance. We compare our results to those of AlOx-based devices, and we discuss the MTJ process optimization and material changes that made the demonstration possible. We present data on key MTJ material attributes for different oxidation processes and

Renu W. Dave; G. Steiner; J. M. Slaughter; J. J. Sun; B. Craigo; S. Pietambaram; K. Smith; G. Grynkewich; M. Deherrera; J. Akerman; S. Tehrani

2006-01-01

136

Perceptual patterning and creativity  

E-print Network

PERCEPTUAL PATTERNING AND CREATIVITY A Thesis by SUSAN PALERMO Approved as to style and content by: Chairman of Committee I r Mem er Member Head of Department December 1981 ABSTRACT Perceptual Patterning and Creativ1ty (December 1981) Susan... Palermo, A, A. , Suffolk County Community College; B. A. , Dowling College Chairman of Advisory Committee: Dr. Bruce 0. Bergum To invest1gate the ~elationship between creativity and perceptual patterning preferences, 180 students across two schools...

Palermo, Susan

2012-06-07

137

The impact of battery capacity and memory bandwidth on CPU speed-setting: a case study  

Microsoft Academic Search

1. ABSTRACT The purpose of this paper is to report the power and performance of an application on a real system as the CPU frequency varies. Previous work in CPU speed-setting considered only the power of the CPU and only CPU’s that vary supply voltage with frequency. This work takes a broader approach, considering total system power, battery capacity and

Thomas L. Martin; Daniel P. Siewiorek

1999-01-01

138

Genetic Variance in Processing Speed Drives Variation in Aging of Spatial and Memory Abilities  

ERIC Educational Resources Information Center

Previous analyses have identified a genetic contribution to the correlation between declines with age in processing speed and higher cognitive abilities. The goal of the current analysis was to apply the biometric dual change score model to consider the possibility of temporal dynamics underlying the genetic covariance between aging trajectories…

Finkel, Deborah; Reynolds, Chandra A.; McArdle, John J.; Hamagami, Fumiaki; Pedersen, Nancy L.

2009-01-01

139

Longitudinal mediation of processing speed on age-related change in memory and fluid intelligence.  

PubMed

Age-related decline in processing speed has long been considered a key driver of cognitive aging. While the majority of empirical evidence for the processing speed hypothesis has been obtained from analyses of between-person age differences, longitudinal studies provide a direct test of within-person change. Using recent developments in longitudinal mediation analysis, we examine the speed-mediation hypothesis at both the within-and between-person levels in two longitudinal studies, Longitudinal Aging Study Amsterdam (LASA) and Origins of Variance in the Oldest-Old (OCTO-Twin). We found significant within-person indirect effects of change in age, such that increasing age was related to lower speed, which in turn relates to lower performance across repeated measures on other cognitive outcomes. Although between-person indirect effects were also significant in LASA, they were not in OCTO-Twin which is not unexpected given the age homogeneous nature of the OCTO-Twin data. A more in-depth examination through measures of effect size suggests that, for the LASA study, the within-person indirect effects were small and between-person indirect effects were consistently larger. These differing magnitudes of direct and indirect effects across levels demonstrate the importance of separating between- and within-person effects in evaluating theoretical models of age-related change. PMID:23957224

Robitaille, Annie; Piccinin, Andrea M; Muniz-Terrera, Graciela; Hoffman, Lesa; Johansson, Boo; Deeg, Dorly J H; Aartsen, Marja J; Comijs, Hannie C; Hofer, Scott M

2013-12-01

140

Relationships among linguistic processing speed, phonological working memory, and attention in children who stutter  

Microsoft Academic Search

Relatively recently, experimental studies of linguistic processing speed in children who stutter (CWS) have emerged, some of which suggest differences in performance among CWS compared to children who do not stutter (CWNS). What is not yet well understood is the extent to which underlying cognitive skills may impact performance on timed tasks of linguistic performance. The purpose of this study

Julie D. Anderson; Stacy A. Wagovich

2010-01-01

141

Relationships among Linguistic Processing Speed, Phonological Working Memory, and Attention in Children Who Stutter  

ERIC Educational Resources Information Center

Relatively recently, experimental studies of linguistic processing speed in children who stutter (CWS) have emerged, some of which suggest differences in performance among CWS compared to children who do not stutter (CWNS). What is not yet well understood is the extent to which underlying cognitive skills may impact performance on timed tasks of…

Anderson, Julie D.; Wagovich, Stacy A.

2010-01-01

142

Cold pressor-induced pain does not impair WAIS-IV processing speed index or working memory index performance.  

PubMed

Chronic pain frequently involves cognitive complaints such as concentration and memory deficits, but studies of the effects of pain on cognition have not consistently demonstrated deficits and have not typically utilized standard neuropsychological instruments. Effects of cold pressor-induced pain on Wechsler Adult Intelligence Scale-Fourth Edition Processing Speed Index (PSI) and Working Memory Index (WMI) performance was examined in nonclinical volunteers (n = 40). All took one PSI subtest and one WMI subtest normally, and then took different PSI and WMI subtests during cold pressor-induced pain or painless warm-water immersion. Scaled scores for normal administration versus pain or painless water immersion did not differ and there was no interaction between group (control vs. pain) and manner of administration, despite moderately severe mean pain ratings (M = 6.8 on a 0-10 pain-rating scale). Results indicate that induced pain in nonclinical volunteers does not impair PSI or WMI performance, and they suggest that chronic pain per se should not be expected to substantially affect these cognitive functions. However, patients with chronic pain may differ from nonclinical volunteers in their experience of pain, potentially limiting generalizability. PMID:24826491

Etherton, Joseph

2014-01-01

143

Relationship between perceptual learning in speech and statistical learning in younger and older adults  

PubMed Central

Within a few sentences, listeners learn to understand severely degraded speech such as noise-vocoded speech. However, individuals vary in the amount of such perceptual learning and it is unclear what underlies these differences. The present study investigates whether perceptual learning in speech relates to statistical learning, as sensitivity to probabilistic information may aid identification of relevant cues in novel speech input. If statistical learning and perceptual learning (partly) draw on the same general mechanisms, then statistical learning in a non-auditory modality using non-linguistic sequences should predict adaptation to degraded speech. In the present study, 73 older adults (aged over 60 years) and 60 younger adults (aged between 18 and 30 years) performed a visual artificial grammar learning task and were presented with 60 meaningful noise-vocoded sentences in an auditory recall task. Within age groups, sentence recognition performance over exposure was analyzed as a function of statistical learning performance, and other variables that may predict learning (i.e., hearing, vocabulary, attention switching control, working memory, and processing speed). Younger and older adults showed similar amounts of perceptual learning, but only younger adults showed significant statistical learning. In older adults, improvement in understanding noise-vocoded speech was constrained by age. In younger adults, amount of adaptation was associated with lexical knowledge and with statistical learning ability. Thus, individual differences in general cognitive abilities explain listeners' variability in adapting to noise-vocoded speech. Results suggest that perceptual and statistical learning share mechanisms of implicit regularity detection, but that the ability to detect statistical regularities is impaired in older adults if visual sequences are presented quickly.

Neger, Thordis M.; Rietveld, Toni; Janse, Esther

2014-01-01

144

Control of sonic fatigue for high-speed flight vehicles using shape memory alloys  

NASA Astrophysics Data System (ADS)

A finite element method for the analysis of thermal deflection and random response is presented for shape memory alloy (SMA) fiber reinforced composite plates subjected to thermal and acoustic loads. The formulation considers the temperature dependent nonlinear material properties of SMAs, the initial deflection and initial stresses, and the geometrical nonlinearity of large thermal deflections. A two-step solution procedure for the combined thermal and acoustic loading is employed consisting of an incremental method for the material nonlinearities and a Newton-Raphson iteration method for prediction of panel responses. Examples are given to show that it is feasible to eliminate the large thermal deflection completely and to reduce the dynamic random response within a given operating temperature range with the proper percentages of SMA volume fraction, prestrain and alloy composition.

Mei, Chuh; Zhong, Zhiwei; Turner, Travis L.

1998-06-01

145

ADHD Subtypes and Co-Occurring Anxiety, Depression, and Oppositional-Defiant Disorder: Differences in Gordon Diagnostic System and Wechsler Working Memory and Processing Speed Index Scores  

ERIC Educational Resources Information Center

Objective: Wechsler Intelligence Scale for Children Freedom-from-Distractibility/Working Memory Index (FDI/WMI), Processing Speed Index (PSI), and Gordon Diagnostic System (GDS) scores in ADHD children were examined as a function of subtype and coexisting anxiety, depression, and oppositional-defiant disorder. Method: Participants were 587…

Mayes, Susan Dickerson; Calhoun, Susan L.; Chase, Gary A.; Mink, Danielle M.; Stagg, Ryan E.

2009-01-01

146

Two Thirds of the Age-Based Changes in Fluid and Crystallized Intelligence, Perceptual Speed, and Memory in Adulthood Are Shared  

ERIC Educational Resources Information Center

Many aspects of cognition decline from middle to late adulthood, but the dimensionality and generality of this decline have rarely been examined. We analyzed 20-year longitudinal data of 6203 middle-aged to very old adults from Greater Manchester and Newcastle-upon-Tyne, UK. Participants were assessed up to eight times on 20 tasks of fluid…

Ghisletta, Paolo; Rabbitt, Patrick; Lunn, Mary; Lindenberger, Ulman

2012-01-01

147

Phase Evolution in Fe-Mn-Si Shape Memory Alloys due to Forging Speed  

NASA Astrophysics Data System (ADS)

The objective of this investigation is to compare the crystallographic characteristics of two different compositions of Fe-Mn-Si alloys forged with the newly designed and constructed High Energy Rate Forming (HERF) hammer with conventional hydraulic and mechanical presses. The degree of martensite formation may depend on metal forming conditions. For both of the alloys, one of the specimens was investigated in as "prepared form", the other specimen was investigated after air cooling with homogenization treatment and three specimens were deformed in different velocities after homogenization treatments. The changes which occurred in the transformation parameters of two FeMnSi alloys with different compositions due to the effects of thermal and mechanical procedures have been studied by using X-ray diffraction. In the alloy specimens cooled to different conditions from the high-temperature ? phase region, ??? and ?????? martensitic transformations were observed. The lattice parameters (LP) of fcc ? and hcp ? structures were determined, and changes in forging speed on the LPs were found.

Eskil, Murat; Kanca, Erdogan

2013-09-01

148

Conceptual short term memory in perception and thought  

E-print Network

Conceptual short term memory (CSTM) is a theoretical construct that provides one answer to the question of how perceptual and conceptual processes are related. CSTM is a mental buffer and processor in which current perceptual ...

Potter, Mary C.

149

Information processing speed, neural efficiency, and working memory performance in multiple sclerosis: differential relationships with structural magnetic resonance imaging.  

PubMed

Multiple sclerosis (MS), a central nervous system (CNS) neurodegenerative disorder, involves lesions of both white and gray matter and reported cognitive impairments that include processing speed (PS), executive function, and working memory (WM). This study closely examined the specifics of these cognitive deficits and their relationship to structural brain damage. A visual n-back task with 3 WM load conditions was used to assess WM performance (task accuracy), PS (reaction time, RT), and a novel measure of processing efficiency (standard deviation of RT, RTSD) in MS patients and controls. These behavioral measures were related to quantitative magnetic resonance imaging (MRI) measures of white and gray matter integrity. Even when MS patients performed as well as controls, as seen for low WM load (0-back), they responded more slowly and were less efficient in their speed of responding. Accuracy findings indicated that the correct match trials were superior to correct nonmatch trials at differentiating MS patients from controls. Further, decreased accuracy during the highest WM load condition was associated with global damage that included both gray and white matter atrophy, while slowed PS and particularly processing inefficiency were associated primarily with white matter atrophy in MS. Importantly, relationships between PS, processing efficiency, performance accuracy, and structural MRI measures were seen only during the highest WM load condition, the condition that required the most executive control. These findings suggest that the MRI/behavioral relationships that were present exclusively during the 2-back condition may reflect connectivity involving frontal cortical systems, the site for executive control. PMID:22047454

Covey, Thomas J; Zivadinov, Robert; Shucard, Janet L; Shucard, David W

2011-12-01

150

High Speed Frequency-Mapping-Based Associative Memory Using Compact Multi-Bit Encoders and a Path-Selecting Scheme  

NASA Astrophysics Data System (ADS)

A compact multi-bit encoding concept for nearest-distance search-speed improvement of scalable and reliable associative-memories utilizing a mapping operation of the distances into frequency space is reported. The distance differences are transformed into signal delays which are finally detected with a time-domain winner-take-all (WTA) circuit. Ring oscillators programmable in discrete frequency steps are used for the distance-frequency mapping. This implementation enables to decrease the effects of process-induced variations, because the step size is a constraint-free design parameter. To further improve the search reliability, frequency dividers are used to enlarge the size of the frequency steps. The multi-bit encoder achieves a substantial search-time reduction by optimizing the basic-ring oscillator delay for distance zero with a path-selecting scheme. The proposed multi-bit encoding concept has been evaluated with two test-chip designs in 180 nm complementary metal oxide semiconductor (CMOS) technology. Search-time reductions by a factor 1.7 in typical search cases and a compact circuit implementation are verified.

Sasaki, Seiryu; Yasuda, Masahiro; Kawabata, Akio; Koide, Tetsushi; Jürgen Mattausch, Hans

2012-04-01

151

Memories.  

ERIC Educational Resources Information Center

This theme issue of the journal "Exploring" covers the topic of "memories" and describes an exhibition at San Francisco's Exploratorium that ran from May 22, 1998 through January 1999 and that contained over 40 hands-on exhibits, demonstrations, artworks, images, sounds, smells, and tastes that demonstrated and depicted the biological,…

Brand, Judith, Ed.

1998-01-01

152

Slow perceptual processing at the core of developmental dyslexia: a parameter-based assessment of visual attention.  

PubMed

The cognitive causes as well as the neurological and genetic basis of developmental dyslexia, a complex disorder of written language acquisition, are intensely discussed with regard to multiple-deficit models. Accumulating evidence has revealed dyslexics' impairments in a variety of tasks requiring visual attention. The heterogeneity of these experimental results, however, points to the need for measures that are sufficiently sensitive to differentiate between impaired and preserved attentional components within a unified framework. This first parameter-based group study of attentional components in developmental dyslexia addresses potentially altered attentional components that have recently been associated with parietal dysfunctions in dyslexia. We aimed to isolate the general attentional resources that might underlie reduced span performance, i.e., either a deficient working memory storage capacity, or a slowing in visual perceptual processing speed, or both. Furthermore, by analysing attentional selectivity in dyslexia, we addressed a potential lateralized abnormality of visual attention, i.e., a previously suggested rightward spatial deviation compared to normal readers. We investigated a group of high-achieving young adults with persisting dyslexia and matched normal readers in an experimental whole report and a partial report of briefly presented letter arrays. Possible deviations in the parametric values of the dyslexic compared to the control group were taken as markers for the underlying deficit. The dyslexic group showed a striking reduction in perceptual processing speed (by 26% compared to controls) while their working memory storage capacity was in the normal range. In addition, a spatial deviation of attentional weighting compared to the control group was confirmed in dyslexic readers, which was larger in participants with a more severe dyslexic disorder. In general, the present study supports the relevance of perceptual processing speed in disorders of written language acquisition and demonstrates that the parametric assessment provides a suitable tool for specifying the underlying deficit within a unitary framework. PMID:21903119

Stenneken, Prisca; Egetemeir, Johanna; Schulte-Körne, Gerd; Müller, Hermann J; Schneider, Werner X; Finke, Kathrin

2011-10-01

153

Processing speed and working memory performance in those with both ADHD and a reading disorder compared with those with ADHD alone.  

PubMed

In previous studies, children with both Attention-Deficit Hyperactivity Disorder (ADHD) and a Reading Disorder were found to have more difficulties with processing speed, working memory, and timed as opposed to non-timed executive functioning (EF) measures when compared with those with either disorder alone. The current study found that older adolescents and adults with both disorders also had more difficulties on processing speed and working memory measures than individuals who only had ADHD. There were no differences among non-timed EF scores. These results add support to the premise that common underlying features may be contributing to the high co-morbidity between these disorders and associated cognitive weaknesses. PMID:21613301

Katz, Lynda J; Brown, Franklin C; Roth, Robert M; Beers, Sue R

2011-08-01

154

ADHD Subtypes and Co-Occurring Anxiety, Depression, and Oppositional-Defiant DisorderDifferences in Gordon Diagnostic System and Wechsler Working Memory and Processing Speed Index Scores  

Microsoft Academic Search

Objective: Wechsler Intelligence Scale for Children Freedom-from-Distractibility\\/Working Memory Index (FDI\\/WMI), Processing Speed Index (PSI), and Gordon Diagnostic System (GDS) scores in ADHD children were examined as a function of subtype and coexisting anxiety, depression, and oppositional-defiant disorder. Method: Participants were 587 children with ADHD combined type (alone, with oppositional-defiant disorder, and with anxiety or depression) and ADHD inattentive type (alone

Susan Dickerson Mayes; Susan L. Calhoun; Gary A. Chase; Danielle M. Mink; Ryan E. Stagg

2009-01-01

155

The Adult Memory and Information Processing Battery (AMIPB) test of information-processing speed: a study of its reliability and feasibility in patients with multiple sclerosis  

Microsoft Academic Search

Objective: To investigate how useful the Adult Memory and Information Processing Battery Task A (AMIPB) is as a test of the speed of information processing in patients with multiple sclerosis (MS) by comparing various methods of presenting the test and assessing the reliability (test–retest and inter-rater) and utility of each version.Design: Each patient was assessed twice verbally by the same

A M M Vlaar; D T Wade

2003-01-01

156

Subjective Confidence in Perceptual Judgments: A Test of the Self-Consistency Model  

ERIC Educational Resources Information Center

Two questions about subjective confidence in perceptual judgments are examined: the bases for these judgments and the reasons for their accuracy. Confidence in perceptual judgments has been claimed to rest on qualitatively different processes than confidence in memory tasks. However, predictions from a self-consistency model (SCM), which had been…

Koriat, Asher

2011-01-01

157

Normative perceptual estimates for 91 healthy subjects age 60-75: impact of age, education, employment, physical exercise, alcohol, and video gaming.  

PubMed

Visual perception serves as the basis for much of the higher level cognitive processing as well as human activity in general. Here we present normative estimates for the following components of visual perception: the visual perceptual threshold, the visual short-term memory (VSTM) capacity and the visual perceptual encoding/decoding speed (processing speed) of VSTM based on an assessment of 91 healthy subjects aged 60-75. The estimates were modeled from input from a whole-report assessment based on a theory of visual attention. In addition to the estimates themselves, we present correlational data, and multiple regression analyses between the estimates and self-reported demographic data and lifestyle variables. The regression statistics suggest that education level, video gaming activity, and employment status may significantly impact the encoding/decoding speed of VTSM but not the capacity of VSTM nor the visual perceptual threshold. The estimates will be useful for future studies into the effects of various types of intervention and training on cognition in general and visual attention in particular. PMID:25339932

Wilms, Inge L; Nielsen, Simon

2014-01-01

158

Normative perceptual estimates for 91 healthy subjects age 60-75: impact of age, education, employment, physical exercise, alcohol, and video gaming  

PubMed Central

Visual perception serves as the basis for much of the higher level cognitive processing as well as human activity in general. Here we present normative estimates for the following components of visual perception: the visual perceptual threshold, the visual short-term memory (VSTM) capacity and the visual perceptual encoding/decoding speed (processing speed) of VSTM based on an assessment of 91 healthy subjects aged 60–75. The estimates were modeled from input from a whole-report assessment based on a theory of visual attention. In addition to the estimates themselves, we present correlational data, and multiple regression analyses between the estimates and self-reported demographic data and lifestyle variables. The regression statistics suggest that education level, video gaming activity, and employment status may significantly impact the encoding/decoding speed of VTSM but not the capacity of VSTM nor the visual perceptual threshold. The estimates will be useful for future studies into the effects of various types of intervention and training on cognition in general and visual attention in particular. PMID:25339932

Wilms, Inge L.; Nielsen, Simon

2014-01-01

159

Perceptual skill in soccer: Implications for talent identification and development  

Microsoft Academic Search

In this review, key components of perceptual skill in soccer are identified and implications for talent identification and development highlighted. Skilled soccer players can recall and recognize patterns of play more effectively than their less skilled counterparts. This ability to encode, retrieve and recognize sport-specific information is due to complex and discriminating long-term memory structures and is crucial to anticipation

A. M. Williams

2000-01-01

160

Prediction Error Associated with the Perceptual Segmentation of Naturalistic Events  

ERIC Educational Resources Information Center

Predicting the near future is important for survival and plays a central role in theories of perception, language processing, and learning. Prediction failures may be particularly important for initiating the updating of perceptual and memory systems and, thus, for the subjective experience of events. Here, we asked observers to make predictions…

Zacks, Jeffrey M.; Kurby, Christopher A.; Eisenberg, Michelle L.; Haroutunian, Nayiri

2011-01-01

161

Perceptual Learning of Acoustic Noise by Individuals with Dyslexia  

ERIC Educational Resources Information Center

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…

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

2014-01-01

162

Perceptual-Motor Dysfunction.  

ERIC Educational Resources Information Center

Discussed are theoretical and treatment aspects of perceptual motor dysfunction and rehabilitation in 4- to 12-year-old academically failing children involved in a 3-year investigation at the University of Kansas. The program is said to stress increasing the amount of stimulation received by sensory receptors of the vestibular, reflex, and haptic…

Pyfer, Jean L.

163

A Perceptual Shape Descriptor  

Microsoft Academic Search

We represent a two dimensional object silhouette by a one dimensional descriptor, which preserves the perceptual structure of its shape. The proposed descriptor is based on the moments of the angles between the bearings of a point on the boundary, in a set of neighborhood systems. At each point on the boundary, the angle between a pair of bearings is

Nafiz Arica; Fatos T. Yarman-vural

2002-01-01

164

Adaptation and perceptual norms  

NASA Astrophysics Data System (ADS)

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.

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

2007-02-01

165

A low-cost high-speed twin-prefetching DSP-based shared- memory system for real-time image processing applications  

NASA Astrophysics Data System (ADS)

This dissertation introduces, investigates, and evaluates a low-cost high-speed twin-prefetching DSP-based bus- interconnected shared-memory system for real-time image processing applications. The proposed architecture can effectively support 32 DSPs in contrast to a maximum of 4 DSPs supported by existing DSP-based bus-interconnected systems. This significant enhancement is achieved by introducing two small programmable fast memories (Twins) between the processor and the shared bus interconnect. While one memory is transferring data from/to the shared memory, the other is supplying the core processor with data. The elimination of the traditional direct linkage of the shared bus and processor data bus makes feasible the utilization of a wider shared bus i.e., shared bus width becomes independent of the data bus width of the processors. The fast prefetching memories and the wider shared bus provide additional bus bandwidth into the system, which eliminates large memory latencies; such memory latencies constitute the major drawback for the performance of shared-memory multiprocessors. Furthermore, in contrast to existing DSP-based uniprocessor or multiprocessor systems the proposed architecture does not require all data to be placed on on-chip or off-chip expensive fast memory in order to reach or maintain peak performance. Further, it can maintain peak performance regardless of whether the processed image is small or large. The performance of the proposed architecture has been extensively investigated executing computationally intensive applications such as real-time high-resolution image processing. The effect of a wide variety of hardware design parameters on performance has been examined. More specifically tables and graphs comprehensively analyze the performance of 1, 2, 4, 8, 16, 32 and 64 DSP-based systems, for a wide variety of shared data interconnect widths such as 32, 64, 128, 256 and 512. In addition, the effect of the wide variance of temporal and spatial locality (present in different applications) on the multiprocessor's execution time is investigated and analyzed. Finally, the prefetching cache-size was varied from a few kilobytes to 4 Mbytes and the corresponding effect on the execution time was investigated. Our performance analysis has clearly showed that the execution time converges to a shallow minimum i.e., it is not sensitive to the size of the prefetching cache. The significance of this observation is that near optimum performance can be achieved with a small (16 to 300 Kbytes) amount of prefetching cache.

Christou, Charalambos Stephanou

1998-11-01

166

Perceptual merging contributes to cueing effects.  

PubMed

An uninformative exogenous cue speeds target detection if cue and target appear in the same location separated by a brief temporal interval. This finding is usually ascribed to the orienting of spatial attention to the cued location. Here we examine the role of perceptual merging of the two trial events in speeded target detection. That is, the cue and target may be perceived as a single event when they appear in the same location. If so, cueing effects could reflect, in part, the binding of the perceived target onset to the earlier cue onset. We observed the traditional facilitation of cued over uncued targets and asked the same observers to judge target onset time by noting the time on a clock when the target appeared. Observers consistently judged the onset time of the target as being earlier than it appeared with cued targets judged as earlier than uncued targets. When the event order is reversed so that the target precedes the cue, perceived onset is accurate in both cued and uncued locations. This pattern of results suggests that perceptual merging does occur in exogenous cueing. A modified attention account is discussed that proposes reentrant processing, evident through perceptual merging, as the underlying mechanism of reflexive orienting of attention. PMID:24961250

Krüger, Hannah M; MacInnes, W Joseph; Hunt, Amelia R

2014-01-01

167

Effects of Acute Cortisol Administration on Perceptual Priming of Trauma-Related Material  

PubMed Central

Intrusive memories are a hallmark symptom of posttraumatic stress disorder (PTSD). They reflect excessive and uncontrolled retrieval of the traumatic memory. Acute elevations of cortisol are known to impair the retrieval of already stored memory information. Thus, continuous cortisol administration might help in reducing intrusive memories in PTSD. Strong perceptual priming for neutral stimuli associated with a “traumatic” context has been shown to be one important learning mechanism that leads to intrusive memories. However, the memory modulating effects of cortisol have only been shown for explicit declarative memory processes. Thus, in our double blind, placebo controlled study we aimed to investigate whether cortisol influences perceptual priming of neutral stimuli that appeared in a “traumatic” context. Two groups of healthy volunteers (N?=?160) watched either neutral or “traumatic” picture stories on a computer screen. Neutral objects were presented in between the pictures. Memory for these neutral objects was tested after 24 hours with a perceptual priming task and an explicit memory task. Prior to memory testing half of the participants in each group received 25 mg of cortisol, the other half received placebo. In the placebo group participants in the “traumatic” stories condition showed more perceptual priming for the neutral objects than participants in the neutral stories condition, indicating a strong perceptual priming effect for neutral stimuli presented in a “traumatic” context. In the cortisol group this effect was not present: Participants in the neutral stories and participants in the “traumatic” stories condition in the cortisol group showed comparable priming effects for the neutral objects. Our findings show that cortisol inhibits perceptual priming for neutral stimuli that appeared in a “traumatic” context. These findings indicate that cortisol influences PTSD-relevant memory processes and thus further support the idea that administration of cortisol might be an effective treatment strategy in reducing intrusive reexperiencing. PMID:25192334

Streb, Markus; Pfaltz, Monique; Michael, Tanja

2014-01-01

168

Perceptual learning and human expertise  

NASA Astrophysics Data System (ADS)

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 learning in areas such as aviation, mathematics, and medicine. Research in perceptual learning promises to advance scientific accounts of learning, and perceptual learning technology may offer similar promise in improving education.

Kellman, Philip J.; Garrigan, Patrick

2009-06-01

169

Neural mechanisms underlying the induction and relief of perceptual curiosity  

PubMed Central

Curiosity is one of the most basic biological drives in both animals and humans, and has been identified as a key motive for learning and discovery. Despite the importance of curiosity and related behaviors, the topic has been largely neglected in human neuroscience; hence little is known about the neurobiological mechanisms underlying curiosity. We used functional magnetic resonance imaging (fMRI) to investigate what happens in our brain during the induction and subsequent relief of perceptual curiosity. Our core findings were that (1) the induction of perceptual curiosity, through the presentation of ambiguous visual input, activated the anterior insula and anterior cingulate cortex (ACC), brain regions sensitive to conflict and arousal; (2) the relief of perceptual curiosity, through visual disambiguation, activated regions of the striatum that have been related to reward processing; and (3) the relief of perceptual curiosity was associated with hippocampal activation and enhanced incidental memory. These findings provide the first demonstration of the neural basis of human perceptual curiosity. Our results provide neurobiological support for a classic psychological theory of curiosity, which holds that curiosity is an aversive condition of increased arousal whose termination is rewarding and facilitates memory. PMID:22347853

Jepma, Marieke; Verdonschot, Rinus G.; van Steenbergen, Henk; Rombouts, Serge A. R. B.; Nieuwenhuis, Sander

2012-01-01

170

A Two-Stage Search of Visual Working Memory: Investigating Speed in the Change-Detection Paradigm  

PubMed Central

A popular procedure for investigating working memory processes has been the visual change-detection procedure. Models of performance in that procedure, however, tend to be based on performance accuracy and to treat working memory search as a one-step process, in which memory representations are compared to a test probe to determine if a match is present. To gain a clearer understanding of how search of these representations operate in the change-detection task, we examined reaction time in two experiments, with a single-item probe either located centrally or at the location of an array item. Contrary to current models of visual working memory capacity, our data point to a two-stage search process: a fast first step to check for the novelty of the probe and, in the absence of such novelty, a second, slower step to search exhaustively for a match between the test probe and a memory representation. In addition to these results, we found that participants tended not to use location information provided by the probe that theoretically could have abbreviated the search process. We suggest some basic revisions of current models of processing in this type of visual working memory task. PMID:25023891

Gilchrist, Amanda L.; Cowan, Nelson

2014-01-01

171

The cognitive effects of listening to background music on older adults: processing speed improves with upbeat music, while memory seems to benefit from both upbeat and downbeat music  

PubMed Central

Background music refers to any music played while the listener is performing another activity. Most studies on this effect have been conducted on young adults, while little attention has been paid to the presence of this effect in older adults. Hence, this study aimed to address this imbalance by assessing the impact of different types of background music on cognitive tasks tapping declarative memory and processing speed in older adults. Overall, background music tended to improve performance over no music and white noise, but not always in the same manner. The theoretical and practical implications of the empirical findings are discussed. PMID:25360112

Bottiroli, Sara; Rosi, Alessia; Russo, Riccardo; Vecchi, Tomaso; Cavallini, Elena

2014-01-01

172

The cognitive effects of listening to background music on older adults: processing speed improves with upbeat music, while memory seems to benefit from both upbeat and downbeat music.  

PubMed

Background music refers to any music played while the listener is performing another activity. Most studies on this effect have been conducted on young adults, while little attention has been paid to the presence of this effect in older adults. Hence, this study aimed to address this imbalance by assessing the impact of different types of background music on cognitive tasks tapping declarative memory and processing speed in older adults. Overall, background music tended to improve performance over no music and white noise, but not always in the same manner. The theoretical and practical implications of the empirical findings are discussed. PMID:25360112

Bottiroli, Sara; Rosi, Alessia; Russo, Riccardo; Vecchi, Tomaso; Cavallini, Elena

2014-01-01

173

Perceptual biases and positive schizotypy: The role of perceptual load  

Microsoft Academic Search

The study investigated the effects of perceptual load on the bias to report seeing non-existing events—a bias associated with positive symptoms of schizophrenia and positive schizotypal symptoms. Undergraduate students completed psychometric measures of schizotypy and were asked to detect fast moving words among non-words under different levels of perceptual load. Perceptual load was manipulated through stimulus motion. Overall, the results

Elias Tsakanikos

2006-01-01

174

The measurement of perceptual curiosity  

Microsoft Academic Search

Perceptual curiosity, as defined by Berlyne (1954), involves interest in and giving attention to novel perceptual stimulation, and motivates visual and sensory-inspection. A 33-item questionnaire constructed to assess individual differences in perceptual curiosity was administered to 320 undergraduate students (202 females; 118 males). The participants also responded to the trait scales of the State-Trait Personality Inventory (STPI), and to selected

Robert P Collins; Jordan A Litman; Charles D Spielberger

2004-01-01

175

Attentional Bias to Threat: A Perceptual Accuracy Approach  

Microsoft Academic Search

To investigate attentional bias to threatening information, the authors propose a new version of the spatial cueing paradigm in which the focus is on perceptual accuracy instead of response speed. In two experiments, healthy volunteers made unspeeded discriminations between three visual targets presented left or right. Each target was preceded by a visual cue (colored rectangle) at either the same

Stefaan Van Damme; Geert Crombez; Lies Notebaert

2008-01-01

176

Exploring Possible Neural Mechanisms of Intelligence Differences Using Processing Speed and Working Memory Tasks: An fMRI Study  

ERIC Educational Resources Information Center

To explore the possible neural foundations of individual differences in intelligence test scores, we examined the associations between Raven's Matrices scores and two tasks that were administered in a functional magnetic resonance imaging (fMRI) setting. The two tasks were an n-back working memory (N = 37) task and inspection time (N = 47). The…

Waiter, Gordon D.; Deary, Ian J.; Staff, Roger T.; Murray, Alison D.; Fox, Helen C.; Starr, John M.; Whalley, Lawrence J.

2009-01-01

177

Working Memory, Processing Speed, and Set-Shifting in Children with Developmental Coordination Disorder and Attention-Deficit-Hyperactivity Disorder  

ERIC Educational Resources Information Center

It has been suggested that the high levels of comorbidity between attention-deficit-hyperactivity disorder (ADHD) and developmental coordination disorder (DCD) may be attributed to a common underlying neurocognitive mechanism. This study assessed whether children with DCD and ADHD share deficits on tasks measuring working memory, set-shifting, and…

Piek, Jan P.; Dyck, Murray J.; Francis, Mona; Conwell, Alistair

2007-01-01

178

Effects of Model-Based and Memory-Based Processing on Speed and Accuracy of Grammar String Generation  

Microsoft Academic Search

Learners are able to use 2 different types of knowledge to perform a skill. One type is a conscious mental model, and the other is based on memories of instances. The authors conducted 3 experiments that manipulated training conditions designed to affect the availability of 1 or both types of knowledge about an artificial grammar. Participants were tested for both

Thomas J. Domangue; Robert C. Mathews; Ron Sun; Lewis G. Roussel; Claire E. Guidry

2004-01-01

179

Balance in machine architecture: Bandwidth on board and offboard, integer/control speed and flops versus memory  

SciTech Connect

The issues to be addressed here are those of ``balance`` in machine architecture. By this, we mean how much emphasis must be placed on various aspects of the system to maximize its usefulness for physics. There are three components that contribute to the utility of a system: How the machine can be used, how big a problem can be attacked, and what the effective capabilities (power) of the hardware are like. The effective power issue is a matter of evaluating the impact of design decisions trading off architectural features such as memory bandwidth and interprocessor communication capabilities. What is studied is the effect these machine parameters have on how quickly the system can solve desired problems. There is a reasonable method for studying this: One selects a few representative algorithms and computes the impact of changing memory bandwidths, and so forth. The only room for controversy here is in the selection of representative problems. The issue of how big a problem can be attacked boils down to a balance of memory size versus power. Although this is a balance issue it is very different than the effective power situation, because no firm answer can be given at this time. The power to memory ratio is highly problem dependent, and optimizing it requires several pieces of physics input, including: how big a lattice is needed for interesting results; what sort of algorithms are best to use; and how many sweeps are needed to get valid results. We seem to be at the threshold of learning things about these issues, but for now, the memory size issue will necessarily be addressed in terms of best guesses, rules of thumb, and researchers` opinions.

Fischler, M.

1992-04-01

180

Stereotype threat prevents perceptual learning.  

PubMed

Stereotype threat (ST) refers to a situation in which a member of a group fears that her or his performance will validate an existing negative performance stereotype, causing a decrease in performance. For example, reminding women of the stereotype "women are bad at math" causes them to perform more poorly on math questions from the SAT and GRE. Performance deficits can be of several types and be produced by several mechanisms. We show that ST prevents perceptual learning, defined in our task as an increasing rate of search for a target Chinese character in a display of such characters. Displays contained two or four characters and half of these contained a target. Search rate increased across a session of training for a control group of women, but not women under ST. Speeding of search is typically explained in terms of learned "popout" (automatic attraction of attention to a target). Did women under ST learn popout but fail to express it? Following training, the women were shown two colored squares and asked to choose the one with the greater color saturation. Superimposed on the squares were task-irrelevant Chinese characters. For women not trained under ST, the presence of a trained target on one square slowed responding, indicating that training had caused the learning of an attention response to targets. Women trained under ST showed no slowing, indicating that they had not learned such an attention response. PMID:20660737

Rydell, Robert J; Shiffrin, Richard M; Boucher, Kathryn L; Van Loo, Katie; Rydell, Michael T

2010-08-10

181

Stereotype threat prevents perceptual learning  

PubMed Central

Stereotype threat (ST) refers to a situation in which a member of a group fears that her or his performance will validate an existing negative performance stereotype, causing a decrease in performance. For example, reminding women of the stereotype “women are bad at math” causes them to perform more poorly on math questions from the SAT and GRE. Performance deficits can be of several types and be produced by several mechanisms. We show that ST prevents perceptual learning, defined in our task as an increasing rate of search for a target Chinese character in a display of such characters. Displays contained two or four characters and half of these contained a target. Search rate increased across a session of training for a control group of women, but not women under ST. Speeding of search is typically explained in terms of learned “popout” (automatic attraction of attention to a target). Did women under ST learn popout but fail to express it? Following training, the women were shown two colored squares and asked to choose the one with the greater color saturation. Superimposed on the squares were task-irrelevant Chinese characters. For women not trained under ST, the presence of a trained target on one square slowed responding, indicating that training had caused the learning of an attention response to targets. Women trained under ST showed no slowing, indicating that they had not learned such an attention response. PMID:20660737

Shiffrin, Richard M.; Boucher, Kathryn L.; Van Loo, Katie; Rydell, Michael T.

2010-01-01

182

Individualized Motor-Perceptual Study.  

ERIC Educational Resources Information Center

This guide is being used in the Individualized Motor-Perceptual Study to determine whether working directly with kindergarten children to improve performance on motor-perceptual tasks will affect reading ability at the end of grades one, two, and three. The 5-year project involves six schools. In this guide, there are tips for teaching, suggested…

Portland Public Schools, OR.

183

Learning, memory, and synesthesia.  

PubMed

People with color-grapheme synesthesia experience color when viewing written letters or numerals, usually with a particular color evoked by each grapheme. Here, we report on data from 11 color-grapheme synesthetes who had startlingly similar color-grapheme pairings traceable to childhood toys containing colored letters. These are the first and only data to show learned synesthesia of this kind in more than a single individual. Whereas some researchers have focused on genetic and perceptual aspects of synesthesia, our results indicate that a complete explanation of synesthesia must also incorporate a central role for learning and memory. We argue that these two positions can be reconciled by thinking of synesthesia as the automatic retrieval of highly specific mnemonic associations, in which perceptual contents are brought to mind in a manner akin to mental imagery or the perceptual-reinstatement effects found in memory studies. PMID:23307940

Witthoft, Nathan; Winawer, Jonathan

2013-03-01

184

Synergistic effect of self-assembled carbon nanopaper and multi-layered interface on shape memory nanocomposite for high speed electrical actuation  

NASA Astrophysics Data System (ADS)

The synergistic effect of self-assembled carbon nanofiber (CNF) nanopaper and the multi-layered interface on the electrical properties and electro-activated recovery behavior of shape memory polymer (SMP) nanocomposites is investigated. The CNFs were self-assembled by deposition into sheets of multi-layered nanopaper form to significantly enhance the bonding strength between the nanopaper and SMP via van der Waals force. The self-assembled multi-layered CNF nanopaper resulted in improved electrical conductivity and temperature distribution in the SMP nanocomposites. This not only significantly enhances the reliability of bonding between the nanopaper and the SMP, resulting in an improved recovery ratio, but also provides high speed electrical actuation.

Lu, Haibao; Liang, Fei; (Jan) Gou, Jihua; Min Huang, Wei; Leng, Jinsong

2014-02-01

185

Associations between AQT processing speed and neuropsychological tests in neuropsychiatric patients.  

PubMed

Associations between A Quick Test of Cognitive Speed (AQT) perceptual and cognitive speed and neuropsychological tests, including the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), Mini Mental State Examination (MMSE), and the Trail Making Test (TMT), were evaluated in 41 neuropsychiatric patients. Neuropsychological and neurological tests, including CT scan, were administered to all of the patients. AQT was also administered to 75 controls. All AQT means differed significantly for patients and controls. Dual-dimension naming time means in the patient group were in the atypical range and indicated generally reduced cognitive speed, whereas controls performed in the normal range. In the patient group, WAIS-III verbal, performance, and full-scale IQ means were in the normal range. AQT perceptual and cognitive speed correlated negatively with WAIS-III P IQ and MMSE scores, and the relationships were nonlinear. The findings support that AQT dual-dimension naming evaluates cognitive speed (i.e., attention, set shifting, working memory) and can be used for first-line or complementary screening for mild or progressive cognitive impairments. PMID:17606529

Nielsen, Niels Peter; Ringström, Roland; Wiig, Elisabeth H; Minthon, Lennart

2007-01-01

186

"Sightblind": perceptual deficits in the "intact" visual field.  

PubMed

Unilateral visual cortex lesions caused by stroke or trauma lead to blindness in contralateral visual field - a condition called homonymous hemianopia. Although the visual field area processed by the uninjured hemisphere is thought to be "intact," it also exhibits marked perceptual deficits in contrast sensitivity, processing speed, and contour integration. Such patients are "sightblind" - their blindness reaches far beyond the primary scotoma. Studies showing perceptual deficits in patients' intact fields are reviewed and implications of these findings are discussed. It is concluded that consequences of partial blindness are greater than previously thought, since perceptual deficits in the "intact" field likely contribute to subjective vision loss in patients with visual field defect. This has important implications for vision diagnosis and rehabilitation. PMID:23805126

Bola, Micha?; Gall, Carolin; Sabel, Bernhard A

2013-01-01

187

Perceptual learning in sensorimotor adaptation  

PubMed Central

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. PMID:23966671

Darainy, Mohammad; Vahdat, Shahabeddin

2013-01-01

188

Perceptual Load Modulates Object-Based Attention  

ERIC Educational Resources Information Center

Two experimental series are reported using both reaction time (RT) and a data-limited perceptual report to examine the effects of perceptual load on object-based attention. Perceptual load was manipulated across 3 levels by increasing the complexity of perceptual judgments. Data from the RT-based experiments showed object-based effects when the…

Ho, Ming-Chou; Atchley, Paul

2009-01-01

189

Si-Baaed Interband Tunneling Devices For High-Speed Logic and LOWPower Memory Applications SeanL. Rornmel, Thomas E. DWon, Paul R. Berger, Roger Lakefl Phillip E, Thompson,' Karl D, Hobart? Alan C. %abaugh,"  

E-print Network

to activate dopants and reduce point defect density. An intrinsic tunnel barrier was incorporated in allSi-Baaed Interband Tunneling Devices For High-Speed Logic and LOWPower Memory Applications Sean superlattice (DG-SL). The key to achieving room temperature NDR is developing tight control of dopant proil

Rommel, Sean

190

The natural input memory model  

Microsoft Academic Search

A new recognition memory model is proposed which differs from the existing memory models in that it operates on natural input. Therefore it is called the natural input memory (N IM) model. A biologically-informed perceptual pre-processing method takes local samples from a natural image and translates these into a feature-vector representation. The feature-vector representations reside in a similarity space in

Joyca P. W. Lacroix; Jaap M. J. Murre; Eric Postma; Jaap van den Herik

2005-01-01

191

Perceptual experience : relations and representations/  

E-print Network

The aim of this dissertation is to elaborate and assess the Relational View of perceptual experience, and to compare it to its main rival, the Representational View. Roughly stated, the core claim of the Relational View ...

Logue, Heather, 1979-

2009-01-01

192

Do people with schizophrenia have differential impairment in episodic memory and/or working memory relative to other cognitive abilities?  

PubMed Central

Efforts to identify differential or core cognitive deficits in schizophrenia have been made for several decades, with limited success. Part of the difficulty in establishing a cognitive profile in schizophrenia is the considerable inter-patient heterogeneity in the level of cognitive impairment associated with this condition. Thus, it may be useful to examine the presence of relative cognitive weaknesses on an intra-patient level. In the present study we examined the rates of significant intra-person differences between crystallized verbal ability versus five other cognitive abilities among 127 persons with schizophrenia or schizoaffective disorder and 127 demographically matched normal comparison (NC) subjects. We found that the rates of significant discrepancies above the NC group base-rates was significantly greater in reference to those discrepancies involving visual memory relative to those associated with auditory memory, working memory, processing speed, and perceptual organization. The findings conflict with prior suggestions that working memory or auditory episodic memory are differential or core deficits in schizophrenia, and highlight the importance of considering visual memory in characterizing the cognitive effects of this condition. PMID:19945256

Palmer, Barton W.; Savla, Gauri N.; Fellows, Ian E.; Twamley, Elizabeth W.; Jeste, Dilip V.; Lacro, Jonathan P.

2009-01-01

193

Understanding processing speed weaknesses among pedophilic child molesters: response style vs. neuropathology.  

PubMed

Research shows that pedophilic (PED) child molesters exhibit slower performance speed and greater performance accuracy when compared to nonpedophilic (N-PED) child molesters or other criminal and noncriminal controls. The purpose of the present study was to examine whether these differences reflect a slow/deliberate response style among PEDS (as we have previously hypothesized; Eastvold, Suchy, & Strassberg, 2011; Suchy, Whittaker, Strassberg, & Eastvold, 2009a, 2009b), or a fundamental neuropathological weakness in processing speed. Data came from a larger study examining neurocognition among sex offenders. Processing speed in three different domains (motor speed, visual-perceptual speed, and visual-motor integration) was examined in 20 phallometrically identified PEDs, 20 N-PEDs, and 20 nonsexual offenders, using both clinical (Finger Tapping, Symbol Search, Digit Symbol Coding) and experimental measures (Inspection Time Task [ITT]). The ITT assessed speed of visual-perceptual processing independent of response speed. On clinical measures, PEDs exhibited slower visual perception [F(2, 57) = 5.24, p = .008] and visual-motor integration [F(2, 57) = 5.02, p = .010] than the other groups, with no differences for simple motor speed. On the ITT, PEDs performed less accurately than the other groups [F(2, 57) = 3.95, p = .025], clearly indicating that slow processing speed cannot be explained by a deliberate response style. Group differences persisted after controlling for other potential confounds (age, estimate IQ, working memory, ethnicity, and substance use). PEDs' slower performance is due to a fundamental neurocognitive weakness, rather than a slow/deliberate response style. These results are consistent with Cantor et al.'s (2008) work identifying white matter abnormalities among PEDs and provide further support for a neurodevelopmental etiology of pedophilia. PMID:24661177

Suchy, Yana; Eastvold, Angela D; Strassberg, Donald S; Franchow, Emilie I

2014-02-01

194

Perceptual-Gestural (Mis)mapping 1 Author's post-print of: Hughes, R. W., Marsh, J. E., & Jones, D. M. (2009). Perceptual-  

E-print Network

(e.g., alternating female-male voices) as compared with single-voice lists were examined. We tested of presenting lists in more than one voice, particularly alternating female-male voices (Greene, 1991). Evidence. M. (2009). Perceptual- gestural (mis)mapping in serial short-term memory: The impact of talker

Royal Holloway, University of London

195

Memory-to-memory connection structures in FPGAs with embedded memory arrays  

Microsoft Academic Search

This paper shows that the speed of FPGAs with large embedded memory arrays can be improved by adding direct programmable connections between the memories. Nets that connect to multiple memory arrays are often difficult to route, and are often part of the critical path of circuit implementations. The memory-to-memory connection structure proposed in this paper allows for the efficient implementation

Steven J. E. Wilton; Jonathan Rose; Zvonko G. Vranesic

1997-01-01

196

Ferroelectric memories  

Microsoft Academic Search

In the past year it has become possible to fabricate ferroelectric thin-film memories onto standard silicon integrated circuits that combine very high speed (30-nanosecond read\\/erase\\/rewrite operation), 5-volt standard silicon logic levels, very high density (2 by 2 micrometer cell size), complete nonvolatility (no standby power required), and extreme radiation hardness. These ferroelectric random-access memories are expected to replace magnetic core

J. F. Scott; C. A. Paz de Araujo

1989-01-01

197

Perceptual Anomalies in Schizophrenia: Integrating Phenomenology and Cognitive Neuroscience  

PubMed Central

From phenomenological and experimental perspectives, research in schizophrenia has emphasized deficits in “higher” cognitive functions, including attention, executive function, as well as memory. In contrast, general consensus has viewed dysfunctions in basic perceptual processes to be relatively unimportant in the explanation of more complex aspects of the disorder, including changes in self-experience and the development of symptoms such as delusions. We present evidence from phenomenology and cognitive neuroscience that changes in the perceptual field in schizophrenia may represent a core impairment. After introducing the phenomenological approach to perception (Husserl, the Gestalt School), we discuss the views of Paul Matussek, Klaus Conrad, Ludwig Binswanger, and Wolfgang Blankenburg on perception in schizophrenia. These 4 psychiatrists describe changes in perception and automatic processes that are related to the altered experience of self. The altered self-experience, in turn, may be responsible for the emergence of delusions. The phenomenological data are compatible with current research that conceptualizes dysfunctions in perceptual processing as a deficit in the ability to combine stimulus elements into coherent object representations. Relationships of deficits in perceptual organization to cognitive and social dysfunction as well as the possible neurobiological mechanisms are discussed. PMID:17118973

Uhlhaas, Peter J.; Mishara, Aaron L.

2007-01-01

198

Perceptual Aberrations Impair Mental Own-Body Transformations  

Microsoft Academic Search

Dysfunctional self and bodily processing have been reported from the schizophrenia spectrum. Here, the authors tested 72 students (40 women) to determine whether performance in a mental own-body transformation task relates to self-rated frequency of spontaneously experienced schizotypal body schema alterations (perceptual aberration). Participants provided speeded left–right decisions concerning the body of a visually depicted human figure (front view vs.

C. Mohr; O. Blanke; P. Brugger

2006-01-01

199

Mental imagery of speech: linking motor and perceptual systems through internal simulation and estimation  

PubMed Central

The neural basis of mental imagery has been investigated by localizing the underlying neural networks, mostly in motor and perceptual systems, separately. However, how modality-specific representations are top-down induced and how the action and perception systems interact in the context of mental imagery is not well understood. Imagined speech production (“articulation imagery”), which induces the kinesthetic feeling of articulator movement and its auditory consequences, provides a new angle because of the concurrent involvement of motor and perceptual systems. On the basis of previous findings in mental imagery of speech, we argue for the following regarding the induction mechanisms of mental imagery and the interaction between motor and perceptual systems: (1) Two distinct top-down mechanisms, memory retrieval and motor simulation, exist to induce estimation in perceptual systems. (2) Motor simulation is sufficient to internally induce the representation of perceptual changes that would be caused by actual movement (perceptual associations); however, this simulation process only has modulatory effects on the perception of external stimuli, which critically depends on context and task demands. Considering the proposed simulation-estimation processes as common mechanisms for interaction between motor and perceptual systems, we outline how mental imagery (of speech) relates to perception and production, and how these hypothesized mechanisms might underpin certain neural disorders. PMID:23226121

Tian, Xing; Poeppel, David

2012-01-01

200

Perceptual Grouping: Selection Assistance for Digital Sketching  

E-print Network

of digital ink. Suggero iden- tifies groups of perceptually related drawing objects. These "perceptual groups technique. The results revealed that Suggero required fewer pen interactions and less pen movement, digital sketching, sketch analysis, selection assistance, interactive whiteboard ACM Classification

Stürzlinger, Wolfgang

201

Sex Differences in Phonological Coding: Alphabet Transformation Speed  

ERIC Educational Resources Information Center

A previous explanation of the sex difference on so-called perceptual speed tests was in terms of a female advantage in accessing and using phonological name codes in making item comparisons. That explanation was extended to a task involving alphabetical transformations without the requirement for comparison of perceptually available items. A…

Majeres, Raymond L.

2007-01-01

202

Carbon Based Resistive Memory  

Microsoft Academic Search

We propose carbon as new resistive memory material for non-volatile memories and compare three allotropes of carbon, namely carbon nanotubes, graphene-like conductive carbon and insulating carbon for their possible application as resistance-change material in high density non-volatile memories. Repetitive high-speed switching and the potential for multi-level programming have been successfully demonstrated.

Franz Kreupl; Rainer Bruchhaus; Petra Majewski; Jan B. Philipp; Ralf Symanczyk; Thomas Happ; Christian Arndt; Mirko Vogt; Roy Zimmermann; Axel Buerke; Andrew P. Graham; Michael Kund

2009-01-01

203

Aftereffect of high-speed motion  

Microsoft Academic Search

A visual illusion known as the motion aftereffect is considered to be the perceptual manifestation of motion sensors that are recovering from adaptation. This aftereffect can be obtained for a specific range of adaptation speeds with its magnitude generally peaking for speeds around 3 deg s-1. The classic motion aftereffect is usually measured with a static test pattern. Here, we

Frans A J Verstraten; Maarten J van der Smagt; Wim A van de Grind

1998-01-01

204

The Intraparietal Sulcus and Perceptual Organization  

Microsoft Academic Search

The structuring of the sensory scene (perceptual organization) profoundly affects what we perceive, and is of increasing clinical interest. In both vision and audition, many cues have been identified that influence perceptual organization, but only a little is known about its neural basis. Previous studies have suggested that auditory cortex may play a role in auditory perceptual organization (also called

Rhodri Cusack

2005-01-01

205

Aging Does Not Affect Brain Patterns of Repetition Effects Associated with Perceptual Priming of Novel Objects  

Microsoft Academic Search

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 BOLD fMRI. Although explicit recognition memory for the figures was reduced in the elder subjects, repetition priming did not differ

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

2008-01-01

206

Exploring the Perceptual Spaces of Faces, Cars and Birds in Children and Adults  

ERIC Educational Resources Information Center

While much developmental research has focused on the strategies that children employ to recognize faces, less is known about the principles governing the organization of face exemplars in perceptual memory. In this study, we tested a novel, child-friendly paradigm for investigating the organization of face, bird and car exemplars. Children ages…

Tanaka, James W.; Meixner, Tamara L.; Kantner, Justin

2011-01-01

207

Perceptual Organization and Linear Algebra  

E-print Network

1 Perceptual Organization and Linear Algebra Charless Fowlkes Computer Science Dept. University sleeves and give it a try! #12;14 #12;15 Encode Pairwise Relationships as a Weighted Graph #12;16 Cut the graph into two pieces #12;17 Algebraic representation of a weighted undirected graph W(i,j) = similarity

Fowlkes, Charless

208

Perceptual Grouping for Contour Extraction  

Microsoft Academic Search

This paper describes an algorithm that efficiently groups line segments into perceptually salient contours in complex images. A measure of affinity between pairs of lines is used to guide group formation and limit the branching factor of the contour search procedure. The extracted contours are ranked, and presented as a contour hierarchy. Our algo- rithm is able to extract salient

Francisco J. Estrada; Allan D. Jepson

2004-01-01

209

Perceptual Learning, Cognition, and Expertise  

ERIC Educational Resources Information Center

Recent research indicates that perceptual learning (PL)--experience-induced changes in the way perceivers extract information--plays a larger role in complex cognitive tasks, including abstract and symbolic domains, than has been understood in theory or implemented in instruction. Here, we describe the involvement of PL in complex cognitive tasks…

Kellman, Philip J.; Massey, Christine M.

2013-01-01

210

Perceptual Training: Educational Development Programs.  

ERIC Educational Resources Information Center

This booklet presents educational programs and activities for perceptual training of 4- to 9-year-olds and older children with learning and reading problems. The development of visual and auditory perception needs to be understood as closely related to and dependent upon other developmental areas, including motor, language, thinking, emotional,…

Tansley, A. E.

211

Developmental Perceptual Exploration and Organization.  

ERIC Educational Resources Information Center

This study investigated the process of perceptual exploration and organization of children as a function of age and sex in two experiments. In Experiment I, 3- to 5-year-old children named the pictures of nine familiar objects arranged in 3 x 3 matrices (exploration tasks) and indicated preference for objects represented in pairs (pair-completion…

Randhawa, Bikkar S.; And Others

212

An analysis of MRAM based memory technologies  

E-print Network

MRAM is a memory (RAM) technology that uses electron spin to store information. Often been called "the ideal memory", it can potentially combine the density of DRAM with the speed of SRAM and non-volatility of FLASH memory ...

Vijayaraghavan, Rangarajan, M. Eng. Massachusetts Institute of Technology

2006-01-01

213

Odor identification: perceptual and semantic dimensions.  

PubMed

Five studies explored identification of odors as an aspect of semantic memory. All dealt in one way or another with the accessibility of acquired olfactory information. The first study examined stability and showed that, consistent with personal reports, people can fail to identify an odor one day yet succeed another. Failure turned more commonly to success than vice versa, and once success occurred it tended to recur. Confidence ratings implied that subjects generally knew the quality of their answers. Even incorrect names, though, often carried considerable information which sometimes reflected a semantic and sometimes a perceptual source of errors. The second study showed that profiling odors via the American Society of Testing and Materials list of attributes, an exercise in depth of processing, effected no increment in the identifiability/accessibility beyond an unelaborated second attempt at retrieval. The third study showed that subjects had only a weak ability to predict the relative recognizability of odors they had failed to identify. Whereas the strength of the feeling that they would 'know' an answer if offered choices did not associate significantly with performance for odors, it did for trivia questions. The fourth study demonstrated an association between ability to discriminate among one set of odors and to identify another, but this emerged only after subjects had received feedback about identity, which essentially changed the task to one of recognition and effectively stabilized access. The fifth study illustrated that feedback improves performance dramatically only for odors involved with it, but that mere retrieval leads to some improvement. The studies suggest a research agenda that could include supplemental use of confidence judgments both retrospectively and prospectively in the same subjects to indicate the amount of accessible semantic information; use of second and third guesses to examine subjects' simultaneously held hypotheses about identity; use of category cuing or similar techniques to discover the minimum semantic information needed to precipitate identification; some use of subjects trained in quantitative descriptive analysis to explore whether such training enhances semantic memory; and judicious use of mixtures to explore perceptual versus semantic errors of identification. PMID:9669044

Cain, W S; de Wijk, R; Lulejian, C; Schiet, F; See, L C

1998-06-01

214

Working Memory and Perception D.M. Wilkes, M. Tugcu, J.E. Hunter, and D. Noelle  

E-print Network

within robotic systems. A system comprised of working memory, short term memory, long term memory in a realistic system involving perceptual systems, actuators, reasoning, and short- and long- term memory system, passing data to and from the short-term and long-term memory modules, as well as acting

215

Dimensional Implicit Memory Priming Deficits in Young ADHD Adults  

E-print Network

The experiment explored the difference between production and identification processes and conceptual and perceptual processes in long-term implicit memory. The first phase consisted of prescreening ADHD (Attention Deficit Hyperactivity Disorder...

Tatman, Christopher G

2012-07-11

216

Motor and Tactile-Perceptual Skill Differences between Individuals with High-Functioning Autism and Typically Developing Individuals Ages 5-21  

ERIC Educational Resources Information Center

We examined motor and tactile-perceptual skills in individuals with high-functioning autism (IHFA) and matched typically developing individuals (TDI) ages 5-21 years. Grip strength, motor speed and coordination were impaired in IHFA compared to matched TDI, and the differences between groups varied with age. Although tactile-perceptual skills of…

Abu-Dahab, Sana M. N.; Skidmore, Elizabeth R.; Holm, Margo B.; Rogers, Joan C.; Minshew, Nancy J.

2013-01-01

217

Improving pulse oximetry pitch perception with multisensory perceptual training.  

PubMed

The pulse oximeter is a critical monitor in anesthesia practice designed to improve patient safety. Here, we present an approach to improve the ability of anesthesiologists to monitor arterial oxygen saturation via pulse oximetry through an audiovisual training process. Fifteen residents' abilities to detect auditory changes in pulse oximetry were measured before and after perceptual training. Training resulted in a 9% (95% confidence interval, 4%-14%, P = 0.0004, t(166) = 3.60) increase in detection accuracy, and a 72-millisecond (95% confidence interval, 40-103 milliseconds, P < 0.0001, t(166) = -4.52) speeding of response times in attentionally demanding and noisy conditions that were designed to simulate an operating room. This study illustrates the benefits of multisensory training and sets the stage for further work to better define the role of perceptual training in clinical anesthesiology. PMID:24846194

Schlesinger, Joseph J; Stevenson, Ryan A; Shotwell, Matthew S; Wallace, Mark T

2014-06-01

218

Voluntary and automatic attentional control of visual working memory  

Microsoft Academic Search

Previous studies of attention-directing cues have focused largely on the effects of cuing on perceptual processes, but cuing\\u000a may also influence the transfer of perceptual representations into visual working memory. In the present study, we examined\\u000a this potential role of cues, using both predictive and nonpredictive cues in the context of a visual working memory task.\\u000a Each trial began with

Brandon K. Schmidt; Edward K. Vogel; Geoffrey F. Woodman; Steven J. Luck

2002-01-01

219

The Sensory Nature of Episodic Memory: Sensory Priming Effects Due to Memory Trace Activation  

ERIC Educational Resources Information Center

The aim of this study was to provide evidence that memory and perceptual processing are underpinned by the same mechanisms. Specifically, the authors conducted 3 experiments that emphasized the sensory aspect of memory traces. They examined their predictions with a short-term priming paradigm based on 2 distinct phases: a learning phase consisting…

Brunel, Lionel; Labeye, Elodie; Lesourd, Mathieu; Versace, Remy

2009-01-01

220

Fractal fluctuations in gaze speed visual search  

Microsoft Academic Search

Visual search involves a subtle coordination of visual memory and lower-order perceptual mechanisms. Specifically, the fluctuations\\u000a in gaze may provide support for visual search above and beyond what may be attributed to memory. Prior research indicates\\u000a that gaze during search exhibits fractal fluctuations, which allow for a wide sampling of the field of view. Fractal fluctuations\\u000a constitute a case of

Damian G. Stephen; Jason Anastas

2011-01-01

221

Optimizing Linked Perceptual Class Formation and Transfer of Function  

ERIC Educational Resources Information Center

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…

Fields, Lanny; Garruto, Michelle

2009-01-01

222

Effects of Perceptual and Conceptual Similarity in Lexical Priming of Young Children Who Stutter: Preliminary Findings  

ERIC Educational Resources Information Center

The purpose of this study was to investigate the influence of conceptual and perceptual properties of words on the speed and accuracy of lexical retrieval of children who do (CWS) and do not stutter (CWNS) during a picture-naming task. Participants consisted of 13 3-5-year-old CWS and the same number of CWNS. All participants had speech, language,…

Hartfield, Kia N.; Conture, Edward G.

2006-01-01

223

Learning to Control Collisions: The Role of Perceptual Attunement and Action Boundaries  

ERIC Educational Resources Information Center

The authors investigated the role of perceptual attunement in an emergency braking task in which participants waited until the last possible moment to slam on the brakes. Effects of the size of the approached object and initial speed on the initiation of braking were used to identify the optical variables on which participants relied at various…

Fajen, Brett R.; Devaney, Michael C.

2006-01-01

224

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

PubMed

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. PMID:25071522

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

2014-01-01

225

Recognition Memory for Realistic Synthetic Faces  

PubMed Central

A series of experiments examined short-term recognition memory for trios of briefly-presented, synthetic human faces derived from three real human faces. The stimuli were graded series of faces, which differed by varying known amounts from the face of the average female. Faces based on each of the three real faces were transformed so as to lie along orthogonal axes in a 3-D face space. Experiment 1 showed that the synthetic faces' perceptual similarity stucture strongly influenced recognition memory. Results were fit by NEMo, a noisy exemplar model of perceptual recognition memory. The fits revealed that recognition memory was influenced both by the similarity of the probe to series items, and by the similarities among the series items themselves. Non-metric multi-dimensional scaling (MDS) showed that faces' perceptual representations largely preserved the 3-D space in which the face stimuli were arrayed. NEMo gave a better account of the results when similarity was defined as perceptual, MDS similarity rather than physical proximity of one face to another. Experiment 2 confirmed the importance of within-list homogeneity directly, without mediation of a model. We discuss the affinities and differences between visual memory for synthetic faces and memory for simpler stimuli. PMID:17948069

Yotsumoto, Yuko; Kahana, Michael J.; Wilson, Hugh R.; Sekuler, Robert

2006-01-01

226

Tracking the Temporal Evolution of a Perceptual Judgement Using a Compelled-Response Task  

PubMed Central

Choice behavior and its neural correlates have been intensely studied with tasks in which a subject makes a perceptual judgement and indicates the result with a motor action. Yet, a question crucial for relating behavior to neural activity remains unresolved: what fraction of a subject’s reaction time (RT) is devoted to the perceptual evaluation step, as opposed to executing the motor report? Making such timing measurements accurately is complicated because RTs reflect both sensory and motor processing, and because speed and accuracy may be traded. To overcome these problems, we designed the compelled-saccade task, a two-alternative forced-choice task in which the instruction to initiate a saccade precedes the appearance of the relevant sensory information. With this paradigm, it is possible to track perceptual performance as a function of the amount of time during which sensory information is available to influence a subject’s choice. The result — the tachometric curve — directly reveals a subject’s perceptual processing capacity independently of motor demands. Psychophysical data, together with modeling and computer-simulation results, reveal that task performance depends on three separable components: the timing of the motor responses, the speed of the perceptual evaluation, and additional cognitive factors. Each can vary quickly, from one trial to the next, or can show stable, longer-term changes. This novel dissociation between sensory and motor processes yields a precise metric of how perceptual capacity varies under various experimental conditions, and serves to interpret choice-related neuronal activity as perceptual, motor, or both. PMID:21653845

Shankar, Swetha; Massoglia, Dino P.; Zhu, Dantong; Costello, M. Gabriela; Stanford, Terrence R.; Salinas, Emilio

2011-01-01

227

Premotor cortex mediates perceptual performance.  

PubMed

Articulatory goals have long been proposed to mediate perception. Examples include direct realist and constructivist (analysis by synthesis) theories of speech perception. Although the activity in brain regions involved with action production has been shown to be present during action observation (Mirror Neuron System), the relationship of this activity to perceptual performance has not been clearly demonstrated at the event level. To this end we used functional magnetic resonance imaging fMRI and magnetoencephalography MEG to measure brain activity for correct and incorrect trials of an auditory phonetic identification in noise task. FMRI analysis revealed activity in the premotor cortex including the neighboring frontal opercular part of Broca's area (PMC/Broca's) for both perception and production tasks involving the same phonetic stimuli (potential mirror system site) that was significantly greater for correct over incorrect perceptual identification trials. Time-frequency analysis of single trials conducted over MEG current localized to PMC/Broca's using a hierarchical variational Bayesian source analysis technique revealed significantly greater event-related synchronization ERS and desynchronization ERD for correct over incorrect trials in the alpha, beta, and gamma frequency range prior to and after stimulus presentation. Together, these fMRI and MEG results are consistent with the hypothesis that articulatory processes serve to facilitate perceptual performance, while further dispelling concerns that activity found in ventral PMC/Broca's (mirror system) is merely a product of covert production of the perceived action. The finding of performance predictive activity prior to stimulus onset as well as activity related to task difficulty instead of information available in stimulation are consistent with constructivist and contrary to direct realist theories of perception. PMID:20184959

Callan, Daniel; Callan, Akiko; Gamez, Mario; Sato, Masa-aki; Kawato, Mitsuo

2010-06-01

228

Parietal lobe and episodic memory: bilateral damage causes impaired free recall of autobiographical memory.  

PubMed

Does the parietal lobe have a critical role in memory? The neuroimaging literature indicates that it has an important role, especially in episodic memory. However, the neuropsychological literature suggests that its role is more limited to attentional, spatial, or imagery aspects of memory. Here, we present data to adjudicate this disagreement. Two patients with bilateral parietal lobe damage received detailed assessments of their autobiographical memories. The results show that although both patients easily recalled various memories, their freely recalled memories were relatively impoverished, lacking in detail. This deficit was ubiquitous, and not limited to spatial or perceptual aspects of memory. The memory deficit disappeared when memory was specifically probed by asking pointed questions. Additional tests show that it is unlikely that their free recall deficit can be explained by general mental imagery problems. In sum, the parietal lobe appears to have a critical role in recollection aspects of episodic memory. PMID:18160649

Berryhill, Marian E; Phuong, Lisa; Picasso, Lauren; Cabeza, Roberto; Olson, Ingrid R

2007-12-26

229

Task Specific Devices and the Perceptual Bottleneck*  

E-print Network

properties of four subsystems of the human action system are described. The subsystems are the link-segment system, the muscular system, the circulatory system, and the nervous system. A methodological dilemma. The characteristics of the human perceptual system lead to the perceptual bottleneck. Information about the dynamics

230

Perceptual decomposition of virtual haptic surfaces  

Microsoft Academic Search

The analysis and construction of virtual haptic surfaces are considered from a perceptual point of view rather than from the dynamics and controls approach of prior work. The authors developed a perceptual decomposition of surface contact sensation by examining three qualities associated with the different stages of interaction with a haptic wall simulation. These qualities are the crispness of initial

Louis B. Rosenberg; Bernard D. Adelstein

1993-01-01

231

Perceptual Differences in Attitudes on Quality Circles.  

ERIC Educational Resources Information Center

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)

Holcomb, Lynn; Berger, Leonard

1986-01-01

232

Continuity and Discontinuity of Perceptual Development.  

ERIC Educational Resources Information Center

Despite external changes such as those of magnitudes, the functional properties of the visual system also improve with increased age. According to Jean Piaget's centration/decentration theory, the process of perceptual development might continue until adulthood and even after. However, perceptual development should not be understood in all of its…

Fischer, Hardi

233

Perceptual Differences between Hippies and College Students  

ERIC Educational Resources Information Center

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)

Brothers, Robert; Gaines, Rosslyn

1973-01-01

234

Learning Motion Style Synthesis from Perceptual Observations  

E-print Network

Learning Motion Style Synthesis from Perceptual Observations Lorenzo Torresani Riya, Inc. lorenzo-dimensional perceptual space. We cast the task of learning to synthesize desired movement styles as a regression problem that the learned model can apply a variety of motion styles to pre-recorded motion sequences and it can extrapolate

Bregler, Christoph

235

Collapse Models and Perceptual Processes  

E-print Network

Theories including a collapse mechanism have been presented various years ago. They are based on a modification of standard quantum mechanics in which nonlinear and stochastic terms are added to the evolution equation. Their principal merits derive from the fact that they are mathematically precise schemes accounting, on the basis of a unique universal dynamical principle, both for the quantum behavior of microscopic systems as well as for the reduction associated to measurement processes and for the classical behavior of macroscopic objects. Since such theories qualify themselves not as new interpretations but as modifications of the standard theory they can be, in principle, tested against quantum mechanics. Recently, various investigations identifying possible crucial test have been discussed. In spite of the extreme difficulty to perform such tests it seems that recent technological developments allow at least to put precise limits on the parameters characterizing the modifications of the evolution equation. Here we will simply mention some of the recent investigations in this direction, while we will mainly concentrate our attention to the way in which collapse theories account for definite perceptual process. The differences between the case of reductions induced by perceptions and those related to measurement procedures by means of standard macroscopic devices will be discussed. On this basis, we suggest a precise experimental test of collapse theories involving conscious observers. We make plausible, by discussing in detail a toy model, that the modified dynamics can give rise to quite small but systematic errors in the visual perceptual process.

G. C. Ghirardi; R. Romano

2014-01-15

236

Building online brand perceptual map.  

PubMed

Many companies have launched their products or services online as a new business focus, but only a few of them have survived the competition and made profits. The most important key to an online business's success is to create "brand value" for the customers. Although the concept of online brand has been discussed in previous studies, there is no empirical study on the measurement of online branding. As Web 2.0 emerges to be critical to online branding, the purpose of this study was to measure Taiwan's major Web sites with a number of personality traits to build a perceptual map for online brands. A pretest identified 10 most representative online brand perceptions. The results of the correspondence analysis showed five groups in the perceptual map. This study provided a practical view of the associations and similarities among online brands for potential alliance or branding strategies. The findings also suggested that brand perceptions can be used with identified consumer needs and behaviors to better position online services. The brand perception map in the study also contributed to a better understanding of the online brands in Taiwan. PMID:18785819

Chiang, I-Ping; Lin, Chih-Ying; Wang, Kaisheng M

2008-10-01

237

Collapse models and perceptual processes  

NASA Astrophysics Data System (ADS)

Theories including a collapse mechanism have been presented various years ago. They are based on a modification of standard quantum mechanics in which nonlinear and stochastic terms are added to the evolution equation. Their principal merits derive from the fact that they are mathematically precise schemes accounting, on the basis of a unique universal dynamical principle, both for the quantum behavior of microscopic systems as well as for the reduction associated to measurement processes and for the classical behavior of macroscopic objects. Since such theories qualify themselves not as new interpretations but as modifications of the standard theory they can be, in principle, tested against quantum mechanics. Recently, various investigations identifying possible crucial test have been discussed. In spite of the extreme difficulty to perform such tests it seems that recent technological developments allow at least to put precise limits on the parameters characterizing the modifications of the evolution equation. Here we will simply mention some of the recent investigations in this direction, while we will mainly concentrate our attention to the way in which collapse theories account for definite perceptual process. The differences between the case of reductions induced by perceptions and those related to measurement procedures by means of standard macroscopic devices will be discussed. On this basis, we suggest a precise experimental test of collapse theories involving conscious observers. We make plausible, by discussing in detail a toy model, that the modified dynamics can give rise to quite small but systematic errors in the visual perceptual process.

Carlo Ghirardi, Gian; Romano, Raffaele

2014-04-01

238

Perceptual estimation obeys Occam's razor.  

PubMed

Theoretical models of unsupervised category learning postulate that humans "invent" categories to accommodate new patterns, but tend to group stimuli into a small number of categories. This "Occam's razor" principle is motivated by normative rules of statistical inference. If categories influence perception, then one should find effects of category invention on simple perceptual estimation. In a series of experiments, we tested this prediction by asking participants to estimate the number of colored circles on a computer screen, with the number of circles drawn from a color-specific distribution. When the distributions associated with each color overlapped substantially, participants' estimates were biased toward values intermediate between the two means, indicating that subjects ignored the color of the circles and grouped different-colored stimuli into one perceptual category. These data suggest that humans favor simpler explanations of sensory inputs. In contrast, when the distributions associated with each color overlapped minimally, the bias was reduced (i.e., the estimates for each color were closer to the true means), indicating that sensory evidence for more complex explanations can override the simplicity bias. We present a rational analysis of our task, showing how these qualitative patterns can arise from Bayesian computations. PMID:24137136

Gershman, Samuel J; Niv, Yael

2013-01-01

239

Perceptual Calibration for Immersive Display Environments  

PubMed Central

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

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

2013-01-01

240

Carbon-based resistive memory  

Microsoft Academic Search

We propose carbon as new resistive memory material for non-volatile memories and compare three allotropes of carbon, namely carbon nanotubes, graphene-like conductive carbon and insulating carbon for their possible application as resistance-change material in high density non-volatile memories. Repetitive high-speed switching and the potential for multi-level programming have been successfully demonstrated.

Franz Kreupl; Rainer Bruchhaus; Petra Majewski; Jan B. Philipp; Ralf Symanczyk; Thomas Happ; Christian Arndt; Mirko Vogt; Roy Zimmermann; Axel Buerke; Andrew P. Graham; Michael Kund

2008-01-01

241

Repetition blindness has a perceptual locus: evidence from online processing of targets in RSVP streams  

NASA Technical Reports Server (NTRS)

Four experiments tested whether repetition blindness (RB; reduced accuracy reporting repetitions of briefly displayed items) is a perceptual or a memory-recall phenomenon. RB was measured in rapid serial visual presentation (RSVP) streams, with the task altered to reduce memory demands. In Experiment 1 only the number of targets (1 vs. 2) was reported, eliminating the need to remember target identities. Experiment 2 segregated repeated and nonrepeated targets into separate blocks to reduce bias against repeated targets. Experiments 3 and 4 required immediate "online" buttonpress responses to targets as they occurred. All 4 experiments showed very strong RB. Furthermore, the online response data showed clearly that the 2nd of the repeated targets is the one missed. The present results show that in the RSVP paradigm, RB occurs online during initial stimulus encoding and decision making. The authors argue that RB is indeed a perceptual phenomenon.

Johnston, James C.; Hochhaus, Larry; Ruthruff, Eric

2002-01-01

242

Embodied Memory Judgments: A Case of Motor Fluency  

ERIC Educational Resources Information Center

It is well known that perceptual and conceptual fluency can influence episodic memory judgments. Here, the authors asked whether fluency arising from the motor system also impacts recognition memory. Past research has shown that the perception of letters automatically activates motor programs of typing actions in skilled typists. In this study,…

Yang, Shu-Ju; Gallo, David A.; Beilock, Sian L.

2009-01-01

243

Modeling Recognition Memory Using the Similarity Structure of Natural Input  

ERIC Educational Resources Information Center

The natural input memory (NAM) model is a new model for recognition memory that operates on natural visual input. A biologically informed perceptual preprocessing method takes local samples (eye fixations) from a natural image and translates these into a feature-vector representation. During recognition, the model compares incoming preprocessed…

Lacroix, Joyca P. W.; Murre, Jaap M. J.; Postma, Eric O.; van den Herik, H. Jaap

2006-01-01

244

Real-time knowledge-based processing of images: application of the online NLPM method to perceptual visual analysis.  

PubMed

Perceptual analysis is an interesting topic in the field of image processing, and can be considered a missing link between image processing and human vision. Of the various forms of perception, one of the most important and best known is shape perception. In this work, a framework based on the online non local patch means (NLPM) method is developed, which is designed to infer possible perceptual observations of an input image using the knowledge images provided. Thanks to the speed of online NLPM, the proposed method can simulate the transformation of the input image to the final perceptual image in real time. In order to improve the performance of the method, a hidden chain series is considered for the model that delivers faster convergence. The capability of the method is evaluated on several well-known perceptual examples. PMID:22562761

Farrahi Moghaddam, Reza; Cheriet, Mohamed

2012-08-01

245

Probing perceptual decisions in rodents  

PubMed Central

The study of perceptual decision-making offers insight into how the brain uses complex, sometimes ambiguous information to guide actions. Understanding the underlying processes and their neural bases requires that one pair recordings and manipulations of neural activity with rigorous psychophysics. Though this research has been traditionally performed in primates, it seems increasingly promising to pursue it at least partly in mice and rats. However, rigorous psychophysical methods are not yet as developed for these rodents as they are for primates. Here we give a brief overview of the sensory capabilities of rodents and of their cortical areas devoted to sensation and decision. We then review methods of psychophysics, focusing on the technical issues that arise in their implementation in rodents. These methods represent a rich set of challenges and opportunities. PMID:23799475

Carandini, Matteo; Churchland, Anne K

2014-01-01

246

Interdisciplinary Adventures in Perceptual Ecology  

NASA Astrophysics Data System (ADS)

A portfolio dissertation that began as acoustic ecology and matured into perceptual ecology, centered on ecomusicology, bioacoustics, and translational audio-based media works with environmental perspectives. The place of music in Western eco-cosmology through time provides a basis for structuring an environmental history of human sound perception. That history suggests that music may stabilize human mental activity, and that an increased musical practice may be essential for the human project. An overview of recent antecedents preceding the emergence of acoustic ecology reveals structural foundations from 20th century culture that underpin modern sound studies. The contextual role that Aldo Leopold, Jacob von Uexkull, John Cage, Marshall McLuhan, and others played in anticipating the development of acoustic ecology as an interdiscipline is detailed. This interdisciplinary aspect of acoustic ecology is defined and defended, while new developments like soundscape ecology are addressed, though ultimately sound studies will need to embrace a broader concept of full-spectrum "sensory" or "perceptual" ecology. The bioacoustic fieldwork done on spawning sturgeon emphasized this necessity. That study yielded scientific recordings and spectrographic analyses of spawning sounds produced by lake sturgeon, Acipenser fulvescens, during reproduction in natural habitats in the Lake Winnebago watershed in Wisconsin. Recordings were made on the Wolf and Embarrass River during the 2011-2013 spawning seasons. Several specimens were dissected to investigate possible sound production mechanisms; no sonic musculature was found. Drumming sounds, ranging from 5 to 7 Hz fundamental frequency, verified the infrasonic nature of previously undocumented "sturgeon thunder". Other characteristic noises of sturgeon spawning including low-frequency rumbles and hydrodynamic sounds were identified. Intriguingly, high-frequency signals resembling electric organ discharges were discovered. These sounds create a distinctive acoustic signature of sturgeon spawning. Media files include concert performance video, sturgeon audio samples, podcasts, radio pieces, music recordings, sound design, and a time-lapse soundscape reconstructed from Aldo Leopold's notes.

Bocast, Christopher S.

247

Perceptual Training Strongly Improves Visual Motion Perception in Schizophrenia  

ERIC Educational Resources Information Center

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…

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

2011-01-01

248

Broad-based visual benefits from training with an integrated perceptual-learning video game.  

PubMed

Perception is the window through which we understand all information about our environment, and therefore deficits in perception due to disease, injury, stroke or aging can have significant negative impacts on individuals' lives. Research in the field of perceptual learning has demonstrated that vision can be improved in both normally seeing and visually impaired individuals, however, a limitation of most perceptual learning approaches is their emphasis on isolating particular mechanisms. In the current study, we adopted an integrative approach where the goal is not to achieve highly specific learning but instead to achieve general improvements to vision. We combined multiple perceptual learning approaches that have individually contributed to increasing the speed, magnitude and generality of learning into a perceptual-learning based video-game. Our results demonstrate broad-based benefits of vision in a healthy adult population. Transfer from the game includes; improvements in acuity (measured with self-paced standard eye-charts), improvement along the full contrast sensitivity function, and improvements in peripheral acuity and contrast thresholds. The use of this type of this custom video game framework built up from psychophysical approaches takes advantage of the benefits found from video game training while maintaining a tight link to psychophysical designs that enable understanding of mechanisms of perceptual learning and has great potential both as a scientific tool and as therapy to help improve vision. PMID:24406157

Deveau, Jenni; Lovcik, Gary; Seitz, Aaron R

2014-06-01

249

Action Control: Independent Effects of Memory and Monocular Viewing on Reaching Accuracy  

ERIC Educational Resources Information Center

Evidence suggests that perceptual networks in the ventral visual pathway are necessary for action control when targets are viewed with only one eye, or when the target must be stored in memory. We tested whether memory-linked (i.e., open-loop versus memory-guided actions) and monocular-linked effects (i.e., binocular versus monocular actions) on…

Westwood, D.A.; Robertson, C.; Heath, M.

2005-01-01

250

False memories and confabulation.  

PubMed

Memory distortions range from the benign (thinking you mailed a check that you only thought about mailing), to the serious (confusing what you heard after a crime with what you actually saw), to the fantastic (claiming you piloted a spaceship). We review theoretical ideas and empirical evidence about the source monitoring processes underlying both true and false memories. Neuropsychological studies show that certain forms of brain damage (such as combined frontal and medial-temporal lesions) might result in profound source confusions, called confabulations. Neuroimaging techniques provide new evidence regarding more specific links between underlying brain mechanisms and the normal cognitive processes involved in evaluating memories. One hypothesis is that the right prefrontal cortex (PFC) subserves heuristic judgments based on easily assessed qualities (such as familiarity or perceptual detail) and the left PFC (or the right and left PFC together) subserves more systematic judgments requiring more careful analysis of memorial qualities or retrieval and evaluation of additional supporting or disconfirming information. Such heuristic and systematic processes can be disrupted not only by brain damage but also, for example, by hypnosis, social demands and motivational factors, suggesting caution in the methods used by `memory exploring' professions (therapists, police officers, lawyers, etc.) in order to avoid inducing false memories. PMID:21227110

Johnson, M K; Raye, C L

1998-04-01

251

Development of Auditory-Vocal Perceptual Skills in Songbirds  

PubMed Central

Songbirds are one of the few groups of animals that learn the sounds used for vocal communication during development. Like humans, songbirds memorize vocal sounds based on auditory experience with vocalizations of adult “tutors”, and then use auditory feedback of self-produced vocalizations to gradually match their motor output to the memory of tutor sounds. In humans, investigations of early vocal learning have focused mainly on perceptual skills of infants, whereas studies of songbirds have focused on measures of vocal production. In order to fully exploit songbirds as a model for human speech, understand the neural basis of learned vocal behavior, and investigate links between vocal perception and production, studies of songbirds must examine both behavioral measures of perception and neural measures of discrimination during development. Here we used behavioral and electrophysiological assays of the ability of songbirds to distinguish vocal calls of varying frequencies at different stages of vocal learning. The results show that neural tuning in auditory cortex mirrors behavioral improvements in the ability to make perceptual distinctions of vocal calls as birds are engaged in vocal learning. Thus, separate measures of neural discrimination and behavioral perception yielded highly similar trends during the course of vocal development. The timing of this improvement in the ability to distinguish vocal sounds correlates with our previous work showing substantial refinement of axonal connectivity in cortico-basal ganglia pathways necessary for vocal learning. PMID:23285011

Miller-Sims, Vanessa C.; Bottjer, Sarah W.

2012-01-01

252

Functional Equivalence and Spatial Path Memory  

Microsoft Academic Search

Loomis, Klatzky, Avraamides, Lippa & Golledge (2007) suggest that, when it comes to spatial information, verbal description and perceptual experience are nearly functionally equivalent with respect to the cognitive representations they produce. We tested this idea for the case of spatial memory for complex paths. Paths consisted entirely of unit-length segments followed by 90-degree turns, thus assuring that a path

Don R. Lyon; Glenn M. Gunzelmann

2011-01-01

253

The Unattended Speech Effect: Perception or Memory?  

Microsoft Academic Search

Broadbent (1983) has suggested that the influence of unattended speech on immediate serial recall is a perceptual phenomenon rather than a memory phenomenon. In order to test this, subjects were required to classify visually presented pairs of consonants on the basis of either case or rhyme. They were tested both in silence and against a background of continuous spoken Arabic

Alan Baddeley; Pierre Salamé

1986-01-01

254

Robot Partners: Collaborative Perceptual Robotic Systems  

E-print Network

Robot Partners: Collaborative Perceptual Robotic Systems Working paper Cooperative Distributed robotic systems, including remote-brained soccer players, visually guided mobile robots, and visual been supported by the the Networks of Centres of Excellence Institute for Robotics and Intelligent

Little, Jim

255

From perceptual to language-mediated categorization  

PubMed Central

From at least two months onwards, infants can form perceptual categories. During the first year of life, object knowledge develops from the ability to represent individual object features to representing correlations between attributes and to integrate information from different sources. At the end of the first year, these representations are shaped by labels, opening the way to conceptual knowledge. Here, we review the development of object knowledge and object categorization over the first year of life. We then present an artificial neural network model that models the transition from early perceptual categorization to categories mediated by labels. The model informs a current debate on the role of labels in object categorization by suggesting that although labels do not act as object features they nevertheless affect perceived similarity of perceptually distinct objects sharing the same label. The model presents the first step of an integrated account from early perceptual categorization to language-based concept learning. PMID:24324235

Westermann, Gert; Mareschal, Denis

2014-01-01

256

Studying real-world perceptual expertise  

PubMed Central

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

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

2014-01-01

257

Geometrically robust perceptual fingerprinting: an asymmetric case  

E-print Network

Geometrically robust perceptual fingerprinting: an asymmetric case Oleksiy Koval, Sviatoslav investigate the impact of the fingerprint length on the error performance of these protocols relaxing. INTRODUCTION Recent advances in modern networking and multimedia technologies have open an access

Genève, Université de

258

Neural correlates of perceptual contributions to nondeclarative memory for faces  

E-print Network

of this effect was consistent with sources within the temporal and occipital cortices of the left hemisphere). Such experience-induced changes develop quickly, can be very long lasting, and can occur even in the absence

Reber, Paul J.

259

Where do we store the memory representations that guide attention?  

PubMed

During the last decade one of the most contentious and heavily studied topics in the attention literature has been the role that working memory representations play in controlling perceptual selection. The hypothesis has been advanced that to have attention select a certain perceptual input from the environment, we only need to represent that item in working memory. Here we summarize the work indicating that the relationship between what representations are maintained in working memory and what perceptual inputs are selected is not so simple. First, it appears that attentional selection is also determined by high-level task goals that mediate the relationship between working memory storage and attentional selection. Second, much of the recent work from our laboratory has focused on the role of long-term memory in controlling attentional selection. We review recent evidence supporting the proposal that working memory representations are critical during the initial configuration of attentional control settings, but that after those settings are established long-term memory representations play an important role in controlling which perceptual inputs are selected by mechanisms of attention. PMID:23444390

Woodman, Geoffrey F; Carlisle, Nancy B; Reinhart, Robert M G

2013-01-01

260

The future of memory  

NASA Astrophysics Data System (ADS)

In the not too distant future, the traditional memory and storage hierarchy of may be replaced by a single Storage Class Memory (SCM) device integrated on or near the logic processor. Traditional magnetic hard drives, NAND flash, DRAM, and higher level caches (L2 and up) will be replaced with a single high performance memory device. The Storage Class Memory paradigm will require high speed (< 100 ns read/write), excellent endurance (> 1012), nonvolatility (retention > 10 years), and low switching energies (< 10 pJ per switch). The International Technology Roadmap for Semiconductors (ITRS) has recently evaluated several potential candidates SCM technologies, including Resistive (or Redox) RAM, Spin Torque Transfer RAM (STT-MRAM), and phase change memory (PCM). All of these devices show potential well beyond that of current flash technologies and research efforts are underway to improve the endurance, write speeds, and scalabilities to be on-par with DRAM. This progress has interesting implications for space electronics: each of these emerging device technologies show excellent resistance to the types of radiation typically found in space applications. Commercially developed, high density storage class memory-based systems may include a memory that is physically radiation hard, and suitable for space applications without major shielding efforts. This paper reviews the Storage Class Memory concept, emerging memory devices, and possible applicability to radiation hardened electronics for space.

Marinella, M.

261

Exploring the use of memory colors for image enhancement  

NASA Astrophysics Data System (ADS)

Memory colors refer to those colors recalled in association with familiar objects. While some previous work introduces this concept to assist digital image enhancement, their basis, i.e., on-screen memory colors, are not appropriately investigated. In addition, the resulting adjustment methods developed are not evaluated from a perceptual view of point. In this paper, we first perform a context-free perceptual experiment to establish the overall distributions of screen memory colors for three pervasive objects. Then, we use a context-based experiment to locate the most representative memory colors; at the same time, we investigate the interactions of memory colors between different objects. Finally, we show a simple yet effective application using representative memory colors to enhance digital images. A user study is performed to evaluate the performance of our technique.

Xue, Su; Tan, Minghui; McNamara, Ann; Dorsey, Julie; Rushmeier, Holly

2014-02-01

262

Memory processes in learning disability subtypes of children born preterm  

Microsoft Academic Search

The purpose of this study was to evaluate immediate auditory and visual memory processes in learning disability subtypes of 40 children born preterm. Three subgroups of children were examined: (a) primary language disability group (n?=?13), (b) perceptual-motor disability group (n?=?14), and (c) no learning disability diagnosis group without identified language or perceptual-motor learning disability (n?=?13). Between-group comparisons indicate no significant

Thomasin E. McCoy; Amy L. Conrad; Lynn C. Richman; Peg C. Nopoulos; Edward F. Bell

2012-01-01

263

Using a multinomial tree model for detecting mixtures in perceptual detection  

PubMed Central

In the area of memory research there have been two rival approaches for memory measurement—signal detection theory (SDT) and multinomial processing trees (MPT). Both approaches provide measures for the quality of the memory representation, and both approaches provide for corrections for response bias. In recent years there has been a strong case advanced for the MPT approach because of the finding of stochastic mixtures on both target-present and target-absent tests. In this paper a case is made that perceptual detection, like memory recognition, involves a mixture of processes that are readily represented as a MPT model. The Chechile (2004) 6P memory measurement model is modified in order to apply to the case of perceptual detection. This new MPT model is called the Perceptual Detection (PD) model. The properties of the PD model are developed, and the model is applied to some existing data of a radiologist examining CT scans. The PD model brings out novel features that were absent from a standard SDT analysis. Also the topic of optimal parameter estimation on an individual-observer basis is explored with Monte Carlo simulations. These simulations reveal that the mean of the Bayesian posterior distribution is a more accurate estimator than the corresponding maximum likelihood estimator (MLE). Monte Carlo simulations also indicate that model estimates based on only the data from an individual observer can be improved upon (in the sense of being more accurate) by an adjustment that takes into account the parameter estimate based on the data pooled across all the observers. The adjustment of the estimate for an individual is discussed as an analogous statistical effect to the improvement over the individual MLE demonstrated by the James–Stein shrinkage estimator in the case of the multiple-group normal model. PMID:25018741

Chechile, Richard A.

2014-01-01

264

Using Virtual Reality to Characterize Episodic Memory Profiles in Amnestic Mild Cognitive Impairment and Alzheimer's Disease: Influence of Active and Passive Encoding  

ERIC Educational Resources Information Center

Most neuropsychological assessments of episodic memory bear little similarity to the events that patients actually experience as memories in daily life. The first aim of this study was to use a virtual environment to characterize episodic memory profiles in an ecological fashion, which includes memory for central and perceptual details,…

Plancher, G.; Tirard, A.; Gyselinck, V.; Nicolas, S.; Piolino, P.

2012-01-01

265

Distortions in memory for visual displays  

NASA Technical Reports Server (NTRS)

Systematic errors in perception and memory present a challenge to theories of perception and memory and to applied psychologists interested in overcoming them as well. A number of systematic errors in memory for maps and graphs are reviewed, and they are accounted for by an analysis of the perceptual processing presumed to occur in comprehension of maps and graphs. Visual stimuli, like verbal stimuli, are organized in comprehension and memory. For visual stimuli, the organization is a consequence of perceptual processing, which is bottom-up or data-driven in its earlier stages, but top-down and affected by conceptual knowledge later on. Segregation of figure from ground is an early process, and figure recognition later; for both, symmetry is a rapidly detected and ecologically valid cue. Once isolated, figures are organized relative to one another and relative to a frame of reference. Both perceptual (e.g., salience) and conceptual factors (e.g., significance) seem likely to affect selection of a reference frame. Consistent with the analysis, subjects perceived and remembered curves in graphs and rivers in maps as more symmetric than they actually were. Symmetry, useful for detecting and recognizing figures, distorts map and graph figures alike. Top-down processes also seem to operate in that calling attention to the symmetry vs. asymmetry of a slightly asymmetric curve yielded memory errors in the direction of the description. Conceptual frame of reference effects were demonstrated in memory for lines embedded in graphs. In earlier work, the orientation of map figures was distorted in memory toward horizontal or vertical. In recent work, graph lines, but not map lines, were remembered as closer to an imaginary 45 deg line than they had been. Reference frames are determined by both perceptual and conceptual factors, leading to selection of the canonical axes as a reference frame in maps, but selection of the imaginary 45 deg as a reference frame in graphs.

Tversky, Barbara

1989-01-01

266

BE710-Fall 2013 Neuroplasticity and Perceptual Learning 1 BE710: Neuroplasticity and Perceptual Learning  

E-print Network

conditions, learn new facts, and develop new skills. If the brain is injured, it tries to repair itselfBE710-Fall 2013 Neuroplasticity and Perceptual Learning 1 BE710: Neuroplasticity and Perceptual Learning Thusday 4-7pm ERB705 44 Cummington str, Boston, Ma 02215 Course director: Prof. Lucia M. Vaina

Vajda, Sandor

267

The flexibility of partial information transmission in the auditory channel: the role of perceptual discriminability.  

PubMed

A stimulus contains multiple attributes. Under certain circumstances, some information can be transmitted to the next cognitive stage before the processing of other information. An examination of partial information transmission is essential in improving our understanding of the mechanism of information processing. By manipulating two attributes, namely, pitch and intensity, this study examined whether the transmission speed of an attribute could be influenced by its perceptual discriminability. Using a choice go/no-go paradigm, this study presented adults with two pieces of pure tones and measured their LRPs. Results showed that pitch and intensity were transmitted earlier as partial information in the high pitch- and intensity-discriminability conditions, respectively. Thus, this study demonstrated that the transmission speed of a certain attribute could be modulated by its perceptual discriminability. PMID:22905969

Gong, Diankun; Ma, Weiyi; Hu, Jiehui; Hu, Qingqing; Lai, Yongxiu; Yao, Dezhong

2012-10-01

268

Cognitive architecture of perceptual organization: from neurons to gnosons.  

PubMed

What, if anything, is cognitive architecture and how is it implemented in neural architecture? Focusing on perceptual organization, this question is addressed by way of a pluralist approach which, supported by metatheoretical considerations, combines complementary insights from representational, connectionist, and dynamic systems approaches to cognition. This pluralist approach starts from a representationally inspired model which implements the intertwined but functionally distinguishable subprocesses of feedforward feature encoding, horizontal feature binding, and recurrent feature selection. As sustained by a review of neuroscientific evidence, these are the subprocesses that are believed to take place in the visual hierarchy in the brain. Furthermore, the model employs a special form of processing, called transparallel processing, whose neural signature is proposed to be gamma-band synchronization in transient horizontal neural assemblies. In neuroscience, such assemblies are believed to mediate binding of similar features. Their formal counterparts in the model are special input-dependent distributed representations, called hyperstrings, which allow many similar features to be processed in a transparallel fashion, that is, simultaneously as if only one feature were concerned. This form of processing does justice to both the high combinatorial capacity and the high speed of the perceptual organization process. A naturally following proposal is that those temporarily synchronized neural assemblies are "gnosons", that is, constituents of flexible self-organizing cognitive architecture in between the relatively rigid level of neurons and the still elusive level of consciousness. PMID:22086351

van der Helm, Peter A

2012-02-01

269

Visuospatial and verbal working memory load: effects on visuospatial vigilance.  

PubMed

In this study, we examined the impact of concurrent verbal and visuospatial working memory demands on performance of a visuospatial successive target detection task. Three hundred and four participants performed a visuospatial vigilance task while simultaneously performing either a spatial or verbal working memory task that either required a memory load during the vigil or did not require a memory load during the vigil. Perceptual sensitivity A' to vigilance target stimuli was reduced by concurrent memory load, both verbal and visuospatial. The decline in perceptual sensitivity to vigilance targets, the vigilance decrement, was steeper for a visuospatial memory task than a verbal memory task, regardless of concurrent memory load. Memory performance after vigilance detection trials was much lower for visuospatial than verbal items, even though memory performance before vigilance detection trials was higher for visuospatial than verbal items. Together, this indicates increased interference when a visuospatial vigilance task is paired with a visuospatial memory task, than when paired with a verbal memory task. Overall, the visuospatial and verbal working memory loads both impacted vigilance target detection, suggesting utilization of common executive resources. There may, however, be domain specific interference, and this may be exacerbated for two visuospatial tasks. PMID:23143034

Helton, William S; Russell, Paul N

2013-02-01

270

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

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…

Wilkinson, Krista M.; McIlvane, William J.

2013-01-01

271

Disruptive Colouration and Perceptual Grouping  

PubMed Central

Camouflage is the primary defence of many animals and includes multiple strategies that interfere with figure-ground segmentation and object recognition. While matching background colours and textures is widespread and conceptually straightforward, less well explored are the optical ‘tricks’, collectively called disruptive colouration, that exploit perceptual grouping mechanisms. Adjacent high contrast colours create false edges, but this is not sufficient for an object’s shape to be broken up; some colours must blend with the background. We test the novel hypothesis that this will be particularly effective when the colour patches on the animal appear to belong to, not merely different background colours, but different background objects. We used computer-based experiments where human participants had to find cryptic targets on artificial backgrounds. Creating what appeared to be bi-coloured foreground objects on bi-coloured backgrounds, we generated colour boundaries that had identical local contrast but either lay within or between (illusory) objects. As predicted, error rates for targets matching what appeared to be different background objects were higher than for targets which had otherwise identical local contrast to the background but appeared to belong to single background objects. This provides evidence for disruptive colouration interfering with higher-level feature integration in addition to previously demonstrated low-level effects involving contour detection. In addition, detection was impeded in treatments where targets were on or in close proximity to multiple background colour or tone boundaries. This is consistent with other studies which show a deleterious influence of visual ‘clutter’ or background complexity on search. PMID:24466337

Espinosa, Irene; Cuthill, Innes C.

2014-01-01

272

Memory Processes in Learning Disability Subtypes of Children Born Preterm  

PubMed Central

The purpose of this study was to evaluate immediate auditory and visual memory processes in learning disability subtypes of 40 children born preterm. Three subgroups of children were examined: (a) primary language disability group (n = 13), (b) perceptual-motor disability group (n = 14), and (c) no learning disability diagnosis group without identified language or perceptual-motor learning disability (n = 13). Between-group comparisons indicate no significant differences in immediate auditory or visual memory performances between language and perceptual-motor learning disability groups. Within-group comparisons revealed that both learning disability groups performed significantly lower on a task of immediate memory when the mode of stimulus presentation and mode of response were visual. PMID:22375897

McCoy, Thomasin E.; Conrad, Amy L.; Richman, Lynn C.; Nopoulos, Peg C.; Bell, Edward F.

2014-01-01

273

Orienting attention in time activates left intraparietal sulcus for both perceptual and motor task goals.  

PubMed

Attention can be directed not only toward a location in space but also to a moment in time ("temporal orienting"). Temporally informative cues allow subjects to predict when an imminent event will occur, thereby speeding responses to that event. In contrast to spatial orienting, temporal orienting preferentially activates left inferior parietal cortex. Yet, left parietal cortex is also implicated in selective motor attention, suggesting its activation during temporal orienting could merely reflect incidental engagement of preparatory motor processes. Using fMRI, we therefore examined whether temporal orienting would still activate left parietal cortex when the cued target required a difficult perceptual discrimination rather than a speeded motor response. Behaviorally, temporal orienting improved accuracy of target identification as well as speed of target detection, demonstrating the general utility of temporal cues. Crucially, temporal orienting selectively activated left inferior parietal cortex for both motor and perceptual versions of the task. Moreover, conjunction analysis formally revealed a region deep in left intraparietal sulcus (IPS) as common to both tasks, thereby identifying it as a core neural substrate for temporal orienting. Despite the context-independent nature of left IPS activation, complementary psychophysiological interaction analysis revealed how the functional connectivity of left IPS changed as a function of task context. Specifically, left IPS activity covaried with premotor activity during motor temporal orienting but with visual extrastriate activity during perceptual temporal orienting, thereby revealing a cooperative network that comprises both temporal orienting and task-specific processing nodes. PMID:21452942

Davranche, Karen; Nazarian, Bruno; Vidal, Franck; Coull, Jennifer

2011-11-01

274

Multisensory perceptual learning and sensory substitution.  

PubMed

One of the most exciting recent findings in neuroscience has been the capacity for neural plasticity in adult humans and animals. Studies of perceptual learning have provided key insights into the mechanisms of neural plasticity and the changes in functional neuroanatomy that it affords. Key questions in this field of research concern how practice of a task leads to specific or general improvement. Although much of this work has been carried out with a focus on a single sensory modality, primarily visual, there is increasing interest in multisensory perceptual learning. Here we will examine how advances in perceptual learning research both inform and can be informed by the development and advancement of sensory substitution devices for blind persons. To allow 'sight' to occur in the absence of visual input through the eyes, visual information can be transformed by a sensory substitution device into a representation that can be processed as sound or touch, and thus give one the potential to 'see' through the ears or tongue. Investigations of auditory, visual and multisensory perceptual learning can have key benefits for the advancement of sensory substitution, and the study of sensory deprivation and sensory substitution likewise will further the understanding of perceptual learning in general and the reverse hierarchy theory in particular. It also has significant importance for the developing understanding of the brain in metamodal terms, where functional brain areas might be best defined by the computations they carry out rather than by their sensory-specific processing role. PMID:23220697

Proulx, Michael J; Brown, David J; Pasqualotto, Achille; Meijer, Peter

2014-04-01

275

Some visual, optometric and perceptual effects of coloured glasses.  

PubMed

We examined 20 individuals who had worn coloured glasses (Irlen filters) for a period of at least 3 months and who claimed to find them beneficial. Sixteen had a history of reading difficulties. The performance of a variety of visual tasks was compared: (1) using the coloured lenses; (2) using neutral density filters of similar photopic transmittance; and (3) using trial lenses to correct any residual refractive error. The coloured lenses appeared to reduce discomfort and susceptibility to anomalous perceptual effects upon viewing grating patterns. They also improved the speed of visual search by a small amount. The lenses had idiosyncratic effects on ocular muscle balance and acuity. They did not affect contrast sensitivity at a spatial frequency of 4 c/deg. PMID:2062541

Wilkins, A; Neary, C

1991-04-01

276

Mapping the perceptual grain of the human retina.  

PubMed

In humans, experimental access to single sensory receptors is difficult to achieve, yet it is crucial for learning how the signals arising from each receptor are transformed into perception. By combining adaptive optics microstimulation with high-speed eye tracking, we show that retinal function can be probed at the level of the individual cone photoreceptor in living eyes. Classical psychometric functions were obtained from cone-sized microstimuli targeted to single photoreceptors. Revealed psychophysically, the cone mosaic also manifests a variable sensitivity to light across its surface that accords with a simple model of cone light capture. Because this microscopic grain of vision could be detected on the perceptual level, it suggests that photoreceptors can act individually to shape perception, if the normally suboptimal relay of light by the eye's optics is corrected. Thus the precise arrangement of cones and the exact placement of stimuli onto those cones create the initial retinal limits on signals mediating spatial vision. PMID:24741057

Harmening, Wolf M; Tuten, William S; Roorda, Austin; Sincich, Lawrence C

2014-04-16

277

Mapping the Perceptual Grain of the Human Retina  

PubMed Central

In humans, experimental access to single sensory receptors is difficult to achieve, yet it is crucial for learning how the signals arising from each receptor are transformed into perception. By combining adaptive optics microstimulation with high-speed eye tracking, we show that retinal function can be probed at the level of the individual cone photoreceptor in living eyes. Classical psychometric functions were obtained from cone-sized microstimuli targeted to single photoreceptors. Revealed psychophysically, the cone mosaic also manifests a variable sensitivity to light across its surface that accords with a simple model of cone light capture. Because this microscopic grain of vision could be detected on the perceptual level, it suggests that photoreceptors can act individually to shape perception, if the normally suboptimal relay of light by the eye's optics is corrected. Thus the precise arrangement of cones and the exact placement of stimuli onto those cones create the initial retinal limits on signals mediating spatial vision. PMID:24741057

Tuten, William S.; Roorda, Austin; Sincich, Lawrence C.

2014-01-01

278

Short-Term Memory Affects Color Perception in Context  

PubMed Central

Color-based object selection — for instance, looking for ripe tomatoes in the market — places demands on both perceptual and memory processes: it is necessary to form a stable perceptual estimate of surface color from a variable visual signal, as well as to retain multiple perceptual estimates in memory while comparing objects. Nevertheless, perceptual and memory processes in the color domain are generally studied in separate research programs with the assumption that they are independent. Here, we demonstrate a strong failure of independence between color perception and memory: the effect of context on color appearance is substantially weakened by a short retention interval between a reference and test stimulus. This somewhat counterintuitive result is consistent with Bayesian estimation: as the precision of the representation of the reference surface and its context decays in memory, prior information gains more weight, causing the retained percepts to be drawn toward prior information about surface and context color. This interaction implies that to fully understand information processing in real-world color tasks, perception and memory need to be considered jointly. PMID:24475131

Olkkonen, Maria; Allred, Sarah R.

2014-01-01

279

Main Memory Database Systems: An Overview  

Microsoft Academic Search

Abstract-Memory resident database systems (MMDB’s) store their data,in main physical memory and provide very high-speed access. Conventional database systems are optimized for the particular,characteristics,of disk,storage,mechanisms.,Memory resident systems, on the other hand, use different optimizations to structure and organize data, as well as to make it reliable. This paper,surveys,the major memory residence optimizations and briefly discusses some of the memory resident

Hector Garcia-molina; Kenneth Salem

1992-01-01

280

Visual perceptual load modulates an auditory microreflex.  

PubMed

The postauricular reflex (PAR) is a vestigial microreflex evoked by an abrupt auditory onset. Previous studies have indicated that the PAR is unaffected by auditory selective attention. Here, we report that the PAR can be modulated by a crossmodal manipulation of attentional demands within the visual modality. Subjects (N=17) performed a central rapid serial visual presentation (RSVP) task while presented with irrelevant auditory distractor probes that elicited the PAR. Visual attentional demands were manipulated by altering the perceptual load of the RSVP task. The PAR modulated systematically with perceptual load, decreasing in amplitude with increased perceptual load. Results indicate that the PAR can be influenced by attention, at least within the visual modality. PMID:19496219

Parks, Nathan A; Hilimire, Matthew R; Corballis, Paul M

2009-05-01

281

On the perceptual organization of speech.  

PubMed

A general account of auditory perceptual organization has developed in the past 2 decades. It relies on primitive devices akin to the Gestalt principles of organization to assign sensory elements to probable groupings and invokes secondary schematic processes to confirm or to repair the possible organization. Although this conceptualization is intended to apply universally, the variety and arrangement of acoustic constituents of speech violate Gestalt principles at numerous junctures, cohering perceptually, nonetheless. The authors report 3 experiments on organization in phonetic perception, using sine wave synthesis to evade the Gestalt rules and the schematic processes alike. These findings falsify a general auditory account, showing that phonetic perceptual organization is achieved by specific sensitivity to the acoustic modulations characteristic of speech signals. PMID:8121955

Remez, R E; Rubin, P E; Berns, S M; Pardo, J S; Lang, J M

1994-01-01

282

Mechanical memory  

DOEpatents

A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

Gilkey, Jeffrey C. (Albuquerque, NM); Duesterhaus, Michelle A. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Renn, Rosemarie A. (Alburquerque, NM); Baker, Michael S. (Albuquerque, NM)

2006-08-15

283

Mechanical memory  

DOEpatents

A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

Gilkey, Jeffrey C. (Albuquerque, NM); Duesterhaus, Michelle A. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Renn, Rosemarie A. (Albuquerque, NM); Baker, Michael S. (Albuquerque, NM)

2006-05-16

284

Explicit pre-training instruction does not improve implicit perceptual-motor sequence learning  

PubMed Central

Memory systems theory argues for separate neural systems supporting implicit and explicit memory in the human brain. Neuropsychological studies support this dissociation, but empirical studies of cognitively healthy participants generally observe that both kinds of memory are acquired to at least some extent, even in implicit learning tasks. A key question is whether this observation reflects parallel intact memory systems or an integrated representation of memory in healthy participants. Learning of complex tasks in which both explicit instruction and practice is used depends on both kinds of memory, and how these systems interact will be an important component of the learning process. Theories that posit an integrated, or single, memory system for both types of memory predict that explicit instruction should contribute directly to strengthening task knowledge. In contrast, if the two types of memory are independent and acquired in parallel, explicit knowledge should have no direct impact and may serve in a “scaffolding” role in complex learning. Using an implicit perceptual-motor sequence learning task, the effect of explicit pre-training instruction on skill learning and performance was assessed. Explicit pre-training instruction led to robust explicit knowledge, but sequence learning did not benefit from the contribution of pre-training sequence memorization. The lack of an instruction benefit suggests that during skill learning, implicit and explicit memory operate independently. While healthy participants will generally accrue parallel implicit and explicit knowledge in complex tasks, these types of information appear to be separately represented in the human brain consistent with multiple memory systems theory. PMID:23280147

Sanchez, Daniel J.; Reber, Paul J.

2012-01-01

285

Image Data Compression Having Minimum Perceptual Error  

NASA Technical Reports Server (NTRS)

A method is presented for performing color or grayscale image compression that eliminates redundant and invisible image components. The image compression uses a Discrete Cosine Transform (DCT) and each DCT coefficient yielded by the transform is quantized by an entry in a quantization matrix which determines the perceived image quality and the bit rate of the image being compressed. The quantization matrix comprises visual masking by luminance and contrast technique all resulting in a minimum perceptual error for any given bit rate, or minimum bit rate for a given perceptual error.

Watson, Andrew B. (Inventor)

1997-01-01

286

Emotional enhancement of perceptual priming is preserved in aging and early-stage Alzheimer's disease.  

PubMed

Perceptual priming for emotionally-negative and neutral scenes was tested in early-stage Alzheimer's disease (AD) patients and healthy younger, middle-aged and older adults. In the study phase, participants rated the scenes for their arousal properties. In the test phase, studied and novel scenes were initially presented subliminally, and the exposure duration was gradually increased until a valence categorization was made. The difference in exposure duration required to categorize novel versus studied items was the dependent measure of priming. Aversive content increased the magnitude of priming, an effect that was preserved in healthy aging and AD. Results from an immediate recognition memory test showed that the priming effects could not be attributable to enhanced explicit memory for the aversive scenes. These findings implicate a dissociation between the modulatory effect of emotion across implicit and explicit forms of memory in aging and early-stage AD. PMID:16154458

LaBar, Kevin S; Torpey, Dana C; Cook, Craig A; Johnson, Stephanie R; Warren, Lauren H; Burke, James R; Welsh-Bohmer, Kathleen A

2005-01-01

287

Visual perceptual learning Zhong-Lin Lu a,  

E-print Network

on perceptual learning reveals important plasticity in adult perceptual systems, and as well as the limitations of learning in perception, Helmholtz (1911) made learning an essential com- ponent in his theories learning in adult human observers has been documented in a wide range of perceptual tasks in visual

Zhou, Yi-Feng

288

Assessing clinically relevant perceptual organization with multidimensional scaling techniques  

Microsoft Academic Search

Multidimensional scaling (MDS) techniques provide a promising measurement strategy for characteriz- ing individual differences in cognitive processing, which many clinical theories associate with the development, maintenance, and treatment of psychopathology. The authors describe the use of deter- ministic and probabilistic MDS techniques for investigating numerous aspects of perceptual organization, such as dimensional attention, perceptual correlation, within-attribute organization, and perceptual variability.

Teresa A. Treat; Richard M. McFall; Richard J. Viken; Robert M. Nosofsky; David B. MacKay; John K. Kruschke

2002-01-01

289

The Neurobiology of Semantic Memory  

PubMed Central

Semantic memory includes all acquired knowledge about the world and is the basis for nearly all human activity, yet its neurobiological foundation is only now becoming clear. Recent neuroimaging studies demonstrate two striking results: the participation of modality-specific sensory, motor, and emotion systems in language comprehension, and the existence of large brain regions that participate in comprehension tasks but are not modality-specific. These latter regions, which include the inferior parietal lobe and much of the temporal lobe, lie at convergences of multiple perceptual processing streams. These convergences enable increasingly abstract, supramodal representations of perceptual experience that support a variety of conceptual functions including object recognition, social cognition, language, and the remarkable human capacity to remember the past and imagine the future. PMID:22001867

Binder, Jeffrey R.; Desai, Rutvik H.

2011-01-01

290

Self-Stimulatory Behavior and Perceptual Reinforcement.  

ERIC Educational Resources Information Center

A detailed hypothesis of the acquisition and maintenance of self-stimulatory behavior is offered, proposing that such behaviors are operant responses whose reinforcers are automatically produced perceptual consequences. Related concepts are discussed, and support for the hypothesis from the areas of sensory reinforcement and sensory deprivation is…

Lovaas, Ivar; And Others

1987-01-01

291

Perceptual Motor Activities in the Home.  

ERIC Educational Resources Information Center

Designed for parents, the guide offers instructions for home activities to supplement the school program for children with perceptual motor disturbances. An individual program sheet is provided; behavioral characteristics and the child's need for structure are explained. Activities detailed include motor planning, body image, fine motor…

Brinning, Dorothy; And Others

292

Perceptual Learning During Action Video Game Playing  

Microsoft Academic Search

Action video games have been shown to enhance behavioral performance on a wide variety of perceptual tasks, from those that require effective allocation of attentional resources across the visual scene, to those that demand the successful identification of fleetingly presented stimuli. Importantly, these effects have not only been shown in expert action video game players, but a causative link has

C. Shawn Green; Renjie Li; Daphne Bavelierb

2009-01-01

293

Using body size to predict perceptual range  

Microsoft Academic Search

We examined the relationship between body size and perceptual range (the distance at which an animal can perceive landscape elements) for a group of forest-dwelling rodents. We used previously published data on orientation ability at various distances for three sciurid species (gray squirrel, fox squirrel and chipmunk) and one murid species (white-footed mouse) to build a predictive model. We found

Stephen G. Mech; Patrick A. Zollner

2002-01-01

294

Modeling Perceptual Attention in Virtual Humans  

Microsoft Academic Search

This paper describes our efforts to model perceptua l attention in virtual humans for the joint synthet ic battlefield. With the exception of the work by Ree ce et al. (19,20) to develop individual combatants, current computer generated forces represent entities at the platform level, hence, the perceptual model of these entiti es is typically a composite representing the behaviors

Randall W. Hill

1999-01-01

295

Perceptual crossing: the simplest online paradigm  

PubMed Central

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

Auvray, Malika; Rohde, Marieke

2012-01-01

296

Using Perceptual Grouping for Object Group Selection  

E-print Network

of proximity, curve-linearity, and closure. We demonstrate the results with several examples. Keywords Perceptual grouping, Gestalt laws, Proximity, Curve- Linearity, Object grouping ACM Classification Keywords H University, 4700 Keele Street Toronto, Ontario, M3J 1P3 Canada hoda@cs.yorku.ca Wolfgang Stuerzlinger

Stürzlinger, Wolfgang

297

Electroglottographic and perceptual evaluation of tracheoesophageal speech.  

PubMed

To optimize tracheoesophageal (TO) speech after total laryngectomy, it is vital to have a robust tool of assessment to help investigate deficiencies, document changes, and facilitate therapy. We sought to evaluate and validate electroglottography (EGG) as an important tool in the multidimensional assessment of TO speech. This study is a cross-sectional study of the largest cohort of TO speakers treated by a single surgeon. A second group of normal laryngeal speakers served as a control group. EGG analysis of both groups using connected speech and sustained vowels was performed. Two trained expert raters undertook perceptual evaluation using two accepted scales. EGG measures were then analyzed for correlation with treatment variables. A separate correlation analysis was performed to identify EGG measures that may be associated with perceptual dimensions. Our data from EGG analysis are similar to data obtained from conventional acoustic signal analysis of TO speakers. Sustained vowel and connected speech parameters were poorer in TO speakers than in normal laryngeal speakers. In perceptual evaluation, only grade (G) of the GRBAS scale and Overall Voice Quality appeared reproducible and reliable. T stage, pharyngeal reconstruction and method of closure, cricopharyngeal myotomy, and postoperative complications appear to be correlated with the EGG measures. Five voice measures-jitter, shimmer, average frequency, normalized noise energy, and irregularity-correlated well with the key dimensions of perceptual assessment. EGG is an important assessment tool of TO speech, and can now be reliably used in a clinical setting. PMID:17490856

Kazi, Rehan; Kanagalingam, Jeeve; Venkitaraman, Ramachandran; Prasad, Vyas; Clarke, Peter; Nutting, Christopher M; Rhys-Evans, Peter; Harrington, Kevin J

2009-03-01

298

Perceptual Simulation in Developing Language Comprehension  

ERIC Educational Resources Information Center

We tested an embodied account of language proposing that comprehenders create perceptual simulations of the events they hear and read about. In Experiment 1, children (ages 7-13 years) performed a picture verification task. Each picture was preceded by a prerecorded spoken sentence describing an entity whose shape or orientation matched or…

Engelen, Jan A. A.; Bouwmeester, Samantha; de Bruin, Anique B. H.; Zwaan, Rolf A.

2011-01-01

299

Perceptual Issues of Augmented and Virtual Environments  

Microsoft Academic Search

For a sensible application of Augmented Reality (AR) and Virtual Environments (VE) it is necessary to include basic human information processing resources and characteristics. Because there is no fully functional model of human perceptual, cognitive, and motor behavior, this requires empirical analyses. Moreover, these analyses are often based on subjective ratings rather than objective measures. With regard to perception as

Helge Renkewitz; Thomas Alexander

300

Perceptual issues in augmented reality revisited  

Microsoft Academic Search

This paper provides a classification of perceptual issues in augmented reality, created with a visual processing and interpretation pipeline in mind. We organize issues into ones related to the environment, capturing, augmentation, display, and individual user differences. We also illuminate issues associated with more recent platforms such as handhelds or projector-camera systems. Throughout, we describe current approaches to addressing these

Ernst Kruijff; J. Edward Swan; Steven Feiner

2010-01-01

301

Predicting Odor Perceptual Similarity from Odor Structure  

PubMed Central

To understand the brain mechanisms of olfaction we must understand the rules that govern the link between odorant structure and odorant perception. Natural odors are in fact mixtures made of many molecules, and there is currently no method to look at the molecular structure of such odorant-mixtures and predict their smell. In three separate experiments, we asked 139 subjects to rate the pairwise perceptual similarity of 64 odorant-mixtures ranging in size from 4 to 43 mono-molecular components. We then tested alternative models to link odorant-mixture structure to odorant-mixture perceptual similarity. Whereas a model that considered each mono-molecular component of a mixture separately provided a poor prediction of mixture similarity, a model that represented the mixture as a single structural vector provided consistent correlations between predicted and actual perceptual similarity (r?0.49, p<0.001). An optimized version of this model yielded a correlation of r?=?0.85 (p<0.001) between predicted and actual mixture similarity. In other words, we developed an algorithm that can look at the molecular structure of two novel odorant-mixtures, and predict their ensuing perceptual similarity. That this goal was attained using a model that considers the mixtures as a single vector is consistent with a synthetic rather than analytical brain processing mechanism in olfaction. PMID:24068899

Weiss, Tali; Frumin, Idan; Khan, Rehan M.; Sobel, Noam

2013-01-01

302

Neural events and perceptual awareness Nancy Kanwisher*  

E-print Network

, and single-unit recordings. It is then argued that our quest should ultimately focus not on mere correlates®cult question: now that we have found a set of neural correlates of perceptual awareness, what are we to do with them? What if anything do they tell us about awareness? It is helpful to consider what exactly

Kanwisher, Nancy

303

Optimal reward harvesting in complex perceptual environments  

E-print Network

value or saliency on choice; thus, it is not known how the brain combines these two variables during Humanities and Social Sciences, California Institute of Technology, Pasadena, CA 91125 Edited by Anne and quickly detectable items)? Understanding how perceptual saliency and value information are combined

Perona, Pietro

304

Late Maturation of Auditory Perceptual Learning  

ERIC Educational Resources Information Center

Adults can improve their performance on many perceptual tasks with training, but when does the response to training become mature? To investigate this question, we trained 11-year-olds, 14-year-olds and adults on a basic auditory task (temporal-interval discrimination) using a multiple-session training regimen known to be effective for adults. The…

Huyck, Julia Jones; Wright, Beverly A.

2011-01-01

305

Deuteranomaly Studied with Four Perceptual Criteria  

Microsoft Academic Search

In the theoretical section of the present paper, we develop our view of the roles played by the perceptual criteria: indistinguishably equal, neither blue nor yellow, neither green nor red, and heterochromatically equally bright. These criteria constitute a vectorial opponent-colour space, a concept used throughout the paper. Within this framework, two new theorems on psychophysical opponent-colour channels are stated. In

HORST SCHEIBNER; THOMAS KREMER

1996-01-01

306

Understanding Perceptual Boundaries in Laparoscopic Surgery  

Microsoft Academic Search

Human perceptual capabilities related to the laparoscopic interaction paradigm are not well known. Its study is important for the design of virtual reality simulators, and for the specification of augmented reality applications that overcome current limitations and provide a supersensing to the surgeon. As part of this work, this article addresses the study of laparoscopic pulling forces. Two definitions are

Pablo Lamata; Enrique J. Gómez; Félix Lamata Hernández; Alfonso Oltra Pastor; Francisco Miguel Sanchez-Margallo; Francisco del Pozo Guerrero

2008-01-01

307

Adaptive Criterion Setting in Perceptual Decision Making  

ERIC Educational Resources Information Center

Pigeons responded in a perceptual categorization task with six different stimuli (shades of gray), three of which were to be classified as "light" or "dark", respectively. Reinforcement probability for correct responses was varied from 0.2 to 0.6 across blocks of sessions and was unequal for correct light and dark responses. Introduction of a new…

Stuttgen, Maik C.; Yildiz, Ali; Gunturkun, Onur

2011-01-01

308

A perceptually-supported sketch editor  

Microsoft Academic Search

The human visual system makes a great deal more of images than the elemental marks on a surface. In the course of viewing, creating, or editing a picture, we actively construct a host of visual structures and relationships as components of sensible interpretations. This paper shows how some of these computational processes can be incorporated into perceptually-supported image editing tools,

Eric Saund; Thomas P. Moran

1994-01-01

309

Generalization of Perceptual Learning of Vocoded Speech  

ERIC Educational Resources Information Center

Recent work demonstrates that learning to understand noise-vocoded (NV) speech alters sublexical perceptual processes but is enhanced by the simultaneous provision of higher-level, phonological, but not lexical content (Hervais-Adelman, Davis, Johnsrude, & Carlyon, 2008), consistent with top-down learning (Davis, Johnsrude, Hervais-Adelman,…

Hervais-Adelman, Alexis G.; Davis, Matthew H.; Johnsrude, Ingrid S.; Taylor, Karen J.; Carlyon, Robert P.

2011-01-01

310

Perceptual Load Influences Selective Attention across Development  

ERIC Educational Resources Information Center

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…

Couperus, Jane W.

2011-01-01

311

Healthy Older Observers Show Equivalent Perceptual-Cognitive Training Benefits to Young Adults for Multiple Object Tracking  

PubMed Central

The capacity to process complex dynamic scenes is of critical importance in real life. For instance, traveling through a crowd while avoiding collisions and maintaining orientation and good motor control requires fluent and continuous perceptual-cognitive processing. It is well documented that effects of healthy aging can influence perceptual-cognitive processes (Faubert, 2002) and that the efficiency of such processes can improve with training even for older adults (Richards et al., 2006). Here we assess the capacity of older participants to improve their tracking speed thresholds in a dynamic, virtual reality environment. Results show that this capacity is significantly affected by healthy aging but that perceptual-cognitive training can significantly reduce age-related effects in older individuals, who show an identical learning function to younger healthy adults. Data support the notion that learning in healthy older persons is maintained for processing complex dynamic scenes. PMID:23761025

Legault, Isabelle; Allard, Remy; Faubert, Jocelyn

2013-01-01

312

Capacity-Speed Relationships in Prefrontal Cortex  

E-print Network

Working memory (WM) capacity and WM processing speed are simple cognitive measures that underlie human performance in complex processes such as reasoning and language comprehension. These cognitive measures have shown to ...

Prabhakaran, Vivek

313

Speeding-up Synchronizations in DSM Multiprocessors  

E-print Network

Speeding-up Synchronizations in DSM Multiprocessors A. de Dios1 , B. Sahelices1 , P. Ib´a~nez2 , V. In Distributed Shared-Memory (DSM) multiprocessors a coherence request is handled by the coherence controller

Zaragoza, Universidad de

314

DMA-aware memory energy management  

Microsoft Academic Search

As increasingly larger memories are used to bridge the widening gap between processor and disk speeds, main mem- ory energy consumption is becoming increasingly dominant. Even though much prior research has been conducted on memory energy management, no study has focused on data servers, where main memory is predominantly accessed by DMAs instead of processors. In this paper, we study

Vivek Pandey; Weihang Jiang; Yuanyuan Zhou; Ricardo Bianchini

2006-01-01

315

Solid State Memory Study Final Report  

NASA Technical Reports Server (NTRS)

Existing and future solid state nonvolatile memory technologies are described and evaluated in this report. Solid state memory technologies can offer size, speed, power, weight, and ruggedness advantages over conventional moving media storage technologoies such as disk or tape. This technology list is a broad sampling of past, present, emerging, and future solid state memory technologies.

Katti, R.

1994-01-01

316

The role of answer fluency and perceptual fluency as metacognitive cues for initiating analytic thinking.  

PubMed

Although widely studied in other domains, relatively little is known about the metacognitive processes that monitor and control behaviour during reasoning and decision-making. In this paper, we examined the conditions under which two fluency cues are used to monitor initial reasoning: answer fluency, or the speed with which the initial, intuitive answer is produced (Thompson, Prowse Turner, & Pennycook, 2011), and perceptual fluency, or the ease with which problems can be read (Alter, Oppenheimer, Epley, & Eyre, 2007). The first two experiments demonstrated that answer fluency reliably predicted Feeling of Rightness (FOR) judgments to conditional inferences and base rate problems, which subsequently predicted the amount of deliberate processing as measured by thinking time and answer changes; answer fluency also predicted retrospective confidence judgments (Experiment 3b). Moreover, the effect of answer fluency on reasoning was independent from the effect of perceptual fluency, establishing that these are empirically independent constructs. In five experiments with a variety of reasoning problems similar to those of Alter et al. (2007), we found no effect of perceptual fluency on FOR, retrospective confidence or accuracy; however, we did observe that participants spent more time thinking about hard to read stimuli, although this additional time did not result in answer changes. In our final two experiments, we found that perceptual disfluency increased accuracy on the CRT (Frederick, 2005), but only amongst participants of high cognitive ability. As Alter et al.'s samples were gathered from prestigious universities, collectively, the data to this point suggest that perceptual fluency prompts additional processing in general, but this processing may results in higher accuracy only for the most cognitively able. PMID:23158572

Thompson, Valerie A; Turner, Jamie A Prowse; Pennycook, Gordon; Ball, Linden J; Brack, Hannah; Ophir, Yael; Ackerman, Rakefet

2013-08-01

317

Upper alpha ERD and absolute power: their meaning for memory performance  

Microsoft Academic Search

A variety of studies have shown that EEG alpha activity in the upper frequency range is associated with different types of cognitive processes, memory performance, perceptual performance and intelligence, but in strikingly different ways. For semantic memory performance we have found that resting or reference power is positively associated with performance, whereas during actual processing of the task, small power

Wolfgang Klimesch; Michael Doppelmayr; Simon Hanslmayr

2006-01-01

318

Neuroanatomical Correlates of Encoding in Episodic Memory: Levels of Processing Effect  

Microsoft Academic Search

Cognitive studies of memory processes demonstrate that memory for stimuli is a function of how they are encoded; stimuli processed semantically are better remembered than those processed in a perceptual or shallow fashion. This study investigates the neural correlates of this cognitive phenomenon. Twelve subjects performed two different cognitive tasks on a series of visually presented nouns. In one task,

Shitij Kapur; Fergus I. M. Craik; Endel Tulving; Alan A. Wilson; Sylvain Houle; Gregory M. Brown

1994-01-01

319

Birth of projection neurons in adult avian brain may be related to perceptual or motor learning  

SciTech Connect

Projection neurons that form part of the motor pathway for song control continue to be produced and to replace older projection neurons in adult canaries and zebra finches. This is shown by combining (3H)thymidine, a cell birth marker, and fluorogold, a retrogradely transported tracer of neuronal connectivity. Species and seasonal comparisons suggest that this process is related to the acquisition of perceptual or motor memories. The ability of an adult brain to produce and replace projection neurons should influence our thinking on brain repair.

Alvarez-Buylla, A.; Kirn, J.R.; Nottebohm, F. (Rockefeller Univ. Field Research Center, Millbrook, NY (USA))

1990-09-21

320

Increasing Speed of Processing With Action Video Games  

E-print Network

-CHOICE RT TASKS The possibility that playing video games affects perceptual and cognitive skills hasIncreasing Speed of Processing With Action Video Games Matthew W.G. Dye, C. Shawn Green, and Daphne of playing action video games significantly reduces reaction times without sacrificing accuracy. Critically

Green, C. Shawn

321

Dazzle Camouflage Affects Speed Perception  

PubMed Central

Movement is the enemy of camouflage: most attempts at concealment are disrupted by motion of the target. Faced with this problem, navies in both World Wars in the twentieth century painted their warships with high contrast geometric patterns: so-called “dazzle camouflage”. Rather than attempting to hide individual units, it was claimed that this patterning would disrupt the perception of their range, heading, size, shape and speed, and hence reduce losses from, in particular, torpedo attacks by submarines. Similar arguments had been advanced earlier for biological camouflage. Whilst there are good reasons to believe that most of these perceptual distortions may have occurred, there is no evidence for the last claim: changing perceived speed. Here we show that dazzle patterns can distort speed perception, and that this effect is greatest at high speeds. The effect should obtain in predators launching ballistic attacks against rapidly moving prey, or modern, low-tech battlefields where handheld weapons are fired from short ranges against moving vehicles. In the latter case, we demonstrate that in a typical situation involving an RPG7 attack on a Land Rover the reduction in perceived speed is sufficient to make the grenade miss where it was aimed by about a metre, which could be the difference between survival or not for the occupants of the vehicle. PMID:21673797

Scott-Samuel, Nicholas E.; Baddeley, Roland; Palmer, Chloe E.; Cuthill, Innes C.

2011-01-01

322

MEMORY MODULATION  

PubMed Central

Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evidence from both animal and human research indicates that emotionally significant experiences activate hormonal and brain systems that regulate the consolidation of newly acquired memories. These effects are integrated through noradrenergic activation of the basolateral amygdala which regulates memory consolidation via interactions with many other brain regions involved in consolidating memories of recent experiences. Modulatory systems not only influence neurobiological processes underlying the consolidation of new information, but also affect other mnemonic processes, including memory extinction, memory recall and working memory. In contrast to their enhancing effects on consolidation, adrenal stress hormones impair memory retrieval and working memory. Such effects, as with memory consolidation, require noradrenergic activation of the basolateral amygdala and interactions with other brain regions. PMID:22122145

Roozendaal, Benno; McGaugh, James L.

2011-01-01

323

Exploring the perceptual spaces of faces, cars and birds in children and adults  

PubMed Central

While much developmental research has focused on the strategies that children employ to recognize faces, less is known about the principles governing the organization of face exemplars in perceptual memory. In this study, we tested a novel, child-friendly paradigm for investigating the organization of face, bird and car exemplars. Children ages 3–4, 5–6, 7–8, 9–10, 11–12 and adults were presented with 50/50 morphs of typical and atypical face, bird and car parent images. Participants were asked to judge whether the 50/50 morph more strongly resembled the typical or the atypical parent image. Young and older children and adults showed a systematic bias to the atypical faces and birds, but no bias toward the atypical cars. Collectively, these findings argue that by the age of 3, children encode and organize faces, birds and cars in a perceptual space that is strikingly similar to that of adults. Category organization for both children and adults follows Krumhansl’s (1978) distance-density principle in which the similarity between two exemplars is jointly determined by their physical appearance and the density of neighboring exemplars in the perceptual space. PMID:21676096

Tanaka, James W.; Meixner, Tamara L.; Kantner, Justin

2011-01-01

324

Stimulus Roving and Flankers Affect Perceptual Learning of Contrast Discrimination in Macaca mulatta  

PubMed Central

‘Stimulus roving’ refers to a paradigm in which the properties of the stimuli to be discriminated vary from trial to trial, rather than being kept constant throughout a block of trials. Rhesus monkeys have previously been shown to improve their contrast discrimination performance on a non-roving task, in which they had to report the contrast of a test stimulus relative to that of a fixed-contrast sample stimulus. Human psychophysics studies indicate that roving stimuli yield little or no perceptual learning. Here, we investigate how stimulus roving influences perceptual learning in macaque monkeys and how the addition of flankers alters performance under roving conditions. Animals were initially trained on a contrast discrimination task under non-roving conditions until their performance levels stabilized. The introduction of roving contrast conditions resulted in a pronounced drop in performance, which suggested that subjects initially failed to heed the sample contrast and performed the task using an internal memory reference. With training, significant improvements occurred, demonstrating that learning is possible under roving conditions. To investigate the notion of flanker-induced perceptual learning, flanker stimuli (30% fixed-contrast iso-oriented collinear gratings) were presented jointly with central (roving) stimuli. Presentation of flanker stimuli yielded substantial performance improvements in one subject, but deteriorations in the other. Finally, after the removal of flankers, performance levels returned to their pre-flanker state in both subjects, indicating that the flanker-induced changes were contingent upon the continued presentation of flankers. PMID:25340335

Thiele, Alexander

2014-01-01

325

Perceptual Spaces: Mathematical Structures to Neural Mechanisms  

PubMed Central

A central goal of neuroscience is to understand how populations of neurons build and manipulate representations of percepts that provide useful information about the environment. This symposium explores the fundamental properties of these representations and the perceptual spaces in which they are organized. Spanning the domains of color, visual texture, environmental sound, music, tactile quality, and odor, we show how the geometric structures of perceptual spaces can be determined experimentally and how these structures provide insights into the principles of neural coding and the neural mechanisms that generate the codes, and into the neural processing of complex sensory stimuli. The diversity of the neural architecture in these different sensory systems provides an opportunity to compare their different solutions to common problems: the need for dimensionality reduction, strategies for topographic or nontopographic mapping, the utility of the higher-order statistical structure inherent in natural sensory stimuli, and the constraints of neural hardware. PMID:24198350

Victor, Jonathan; McDermott, Josh; Geffen, Maria; Bensmaia, Sliman; Cleland, Thomas A.

2013-01-01

326

Perceptual spaces: mathematical structures to neural mechanisms.  

PubMed

A central goal of neuroscience is to understand how populations of neurons build and manipulate representations of percepts that provide useful information about the environment. This symposium explores the fundamental properties of these representations and the perceptual spaces in which they are organized. Spanning the domains of color, visual texture, environmental sound, music, tactile quality, and odor, we show how the geometric structures of perceptual spaces can be determined experimentally and how these structures provide insights into the principles of neural coding and the neural mechanisms that generate the codes, and into the neural processing of complex sensory stimuli. The diversity of the neural architecture in these different sensory systems provides an opportunity to compare their different solutions to common problems: the need for dimensionality reduction, strategies for topographic or nontopographic mapping, the utility of the higher-order statistical structure inherent in natural sensory stimuli, and the constraints of neural hardware. PMID:24198350

Zaidi, Qasim; Victor, Jonathan; McDermott, Josh; Geffen, Maria; Bensmaia, Sliman; Cleland, Thomas A

2013-11-01

327

Edge-based perceptual image coding.  

PubMed

We develop a novel psychovisually motivated edge-based low-bit-rate image codec. It offers a compact description of scale-invariant second-order statistics of natural images, the preservation of which is crucial to the perceptual quality of coded images. Although being edge based, the codec does not explicitly code the edge geometry. To save bits on edge descriptions, a background layer of the image is first coded and transmitted, from which the decoder estimates the trajectories of significant edges. The edge regions are then refined by a residual coding technique based on edge dilation and sequential scanning in the edge direction. Experimental results show that the new image coding technique outperforms the existing ones in both objective and perceptual quality, particularly at low bit rates. PMID:21997263

Niu, Yi; Wu, Xiaolin; Shi, Guangming; Wang, Xiaotian

2012-04-01

328

Memory Hierarchy Hardware-Software Co-design in Embedded Systems  

E-print Network

The memory hierarchy is the main bottleneck in modern computer systems as the gap between the speed of the processor and the memory continues to grow larger. The situation in embedded systems is even worse. The memory ...

Ge, Zhiguo

329

Perceptual uniformity of commonly used color spaces  

NASA Astrophysics Data System (ADS)

Use of color images in medical imaging has increased significantly the last few years. Color information is essential for applications such as ophthalmology, dermatology and clinical photography. Use of color at least brings benefits for other applications such as endoscopy, laparoscopy and digital pathology. Remarkably, as of today, there is no agreed standard on how color information needs to be visualized for medical applications. This lack of standardization results in large variability of how color images are visualized and it makes quality assurance a challenge. For this reason FDA and ICC recently organized a joint summit on color in medical imaging (CMI). At this summit, one of the suggestions was that modalities such as digital pathology could benefit from using a perceptually uniform color space (T. Kimpe, "Color Behavior of Medical Displays," CMI presentation, May 2013). Perceptually uniform spaces have already been used for many years in the radiology community where the DICOM GSDF standard provides linearity in luminance but not in color behavior. In this paper we quantify perceptual uniformity, using CIE's ?E2000 as a color distance metric, of several color spaces that are typically used for medical applications. We applied our method to theoretical color spaces Gamma 1.8, 2.0, & 2.2, standard sRGB, and DICOM (correction LUT for gray applied to all primaries). In addition, we also measured color spaces (i.e., native behavior) of a high-end medical display (Barco Coronis Fusion 6MP DL, MDCC-6130), and a consumer display (Dell 1907FP). Our results indicate that sRGB & the native color space on the Barco Coronis Fusion exhibit the least non-uniformity within their group. However, the remaining degree of perceptual non-uniformity is still significant and there is room for improvement.

Avanaki, Ali; Espig, Kathryn; Kimpe, Tom; Xthona, Albert; Marchessoux, Cedric; Rostang, Johan; Piepers, Bastian

2014-03-01

330

Encoding, Memory, and Transcoding Deficits in Childhood Apraxia of Speech  

ERIC Educational Resources Information Center

A central question in Childhood Apraxia of Speech (CAS) is whether the core phenotype is limited to transcoding (planning/programming) deficits or if speakers with CAS also have deficits in auditory-perceptual "encoding" (representational) and/or "memory" (storage and retrieval of representations) processes. We addressed this and other questions…

Shriberg, Lawrence D.; Lohmeier, Heather L.; Strand, Edythe A.; Jakielski, Kathy J.

2012-01-01

331

Cognitive approaches to the development of short-term memory  

Microsoft Academic Search

The capacity to retain information for brief periods of time increases dramatically during the childhood years. The increases in temporary storage of speech-based material that take place in the period spanning the pre-school years and adolescence reflect complex changes in many of the different component processes, including perceptual analysis, construction and maintenance of a memory trace, retention of order information,

Susan E. Gathercole

1999-01-01

332

Constraining theories of semantic memory processing: Evidence from Dementia  

Microsoft Academic Search

In this paper we analyse the performance of ten patients with Dementia of the Alzheimer's Type (D.A.T.) who show a pattern of performance suggesting a deficit at the level of semantic memory in the face of normal visual perceptual processing. We use the results of their performance on probe questions for pictures and words to evaluate several hypotheses arising from

Howard Chertkow; Daniel Bub; David Caplan

1992-01-01

333

Intersensory Redundancy Enhances Memory in Bobwhite Quail Embryos  

ERIC Educational Resources Information Center

Information presented concurrently and redundantly to 2 or more senses (intersensory redundancy) has been shown to recruit attention and promote perceptual learning of amodal stimulus properties in animal embryos and human infants. This study examined whether the facilitative effect of intersensory redundancy also extends to the domain of memory.…

Lickliter, Robert; Bahrick, Lorraine E.; Honeycutt, Hunter

2004-01-01

334

Motor Representations In Memory And Mental Models: Embodiment in Cognition  

Microsoft Academic Search

A variety of experimental results have suggested that motor systems can participate in what were thought to be purely perceptual tasks. Extending previous work in the stimulus- response compatibility paradigm, we show that a representation of a visual stimulus accessed from memory can activate potential motor interactions. Other research has shown that mental images and mental models can have analogue

Daniel C. Richardson; Michael J. Spivey

335

Perceptual inferences about indeterminate arrangements of figures.  

PubMed

Previous studies in spatial propositional reasoning showed that adults use a particular strategy for making representations and inferences from indeterminate descriptions (those consistent with different alternatives). They do not initially represent all the alternatives, but construct a unified mental representation that includes a kind of mental footnote. Only when the task requires access to alternatives is the unified representation re-inspected. The degree of generalisation of this proposal to other perceptual situations was evaluated in three experiments with children, adolescents and adults, using a perceptual inference task with diagrammatic premises that gave information about the location of one of three possible objects. Results obtained with this very quick perceptual task support the kind of representation proposed from propositional spatial reasoning studies. However, children and adults differed in accuracy, with the results gradually changing with age: indeterminacy leads adults to require extra time for understanding and inferring alternatives, whereas children commit errors. These results could help inform us of how people can make inferences from diagrammatic information and make wrong interpretations. PMID:24607441

Moreno-Ríos, Sergio; Rojas-Barahona, Cristian A; García-Madruga, Juan A

2014-05-01

336

Learning problems, delayed perceptual development, and puberty  

NASA Astrophysics Data System (ADS)

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.

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

2003-04-01

337

Perceptual asymmetries and handedness: a neglected link?  

PubMed Central

Healthy individuals tend to weigh in more the left than the right side of visual space in a variety of contexts, ranging from pseudoneglect to perceptual asymmetries for faces. Among the common explanations proposed for the attentional and perceptual advantages of the left visual field, a link with the prevalence of right-handedness in humans has never been suggested, although some evidence seems to converge in favor of a bias of spatial attention toward the region most likely coincident with another person’s right hand during a face-to-face interaction. Such a bias might imply an increased efficiency in monitoring both communicative and aggressive acts, the right limb being more used than the left in both types of behavior. Although attentional and perceptual asymmetries could be linked to right-handedness at the level of phylogeny because of the evolutionarily advantage of directing attention toward the region where others’ dominant hand usually operates, it is also legitimate to question whether, at the ontogenetic level, frequent exposure to right-handed individuals may foster leftward biases. These views are discussed in the light of extant literature, and a number of tests are proposed in order to assess our hypotheses. PMID:24592250

Marzoli, Daniele; Prete, Giulia; Tommasi, Luca

2014-01-01

338

Self-stimulatory behavior and perceptual reinforcement.  

PubMed Central

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

Lovaas, I; Newsom, C; Hickman, C

1987-01-01

339

The perceptual reality of synesthetic colors  

PubMed Central

Synesthesia is a remarkable, rare condition where an individual has multimodal perceptual experiences from a unimodal sensory event. We have studied such an individual, an adult male for whom achromatic words and alphanumeric characters are seen in vivid, reliable colors. We used a variety of perceptual tasks to document the perceptual reality of synesthetic colors and to begin to localize the stage of visual processing where this anomalous binding of externally specified form and internally generated color may take place. Synesthetic colors were elicited by forms defined solely by binocular cues or solely by motion cues, which implies a central locus of visual processing for synesthetic binding of form and color. Also included among our measurements was a difficult visual search task on which non-synesthetic subjects required an effortful search through the visual display. Our subject, in contrast to non-synesthetic subjects, accomplished the task with relative ease because the target of the search had a different synesthetic color from the distractors. Thus, synesthetic experiences appear to originate from a binding of color and form that takes place within central stages of visual processing. PMID:11904456

Palmeri, Thomas J.; Blake, Randolph; Marois, Rene; Flanery, Marci A.; Whetsell, William

2002-01-01

340

Perceptual and Neural Olfactory Similarity in Honeybees  

PubMed Central

The question of whether or not neural activity patterns recorded in the olfactory centres of the brain correspond to olfactory perceptual measures remains unanswered. To address this question, we studied olfaction in honeybees Apis mellifera using the olfactory conditioning of the proboscis extension response. We conditioned bees to odours and tested generalisation responses to different odours. Sixteen odours were used, which varied both in their functional group (primary and secondary alcohols, aldehydes and ketones) and in their carbon-chain length (from six to nine carbons).The results obtained by presentation of a total of 16 × 16 odour pairs show that (i) all odorants presented could be learned, although acquisition was lower for short-chain ketones; (ii) generalisation varied depending both on the functional group and the carbon-chain length of odours trained; higher generalisation was found between long-chain than between short-chain molecules and between groups such as primary and secondary alcohols; (iii) for some odour pairs, cross-generalisation between odorants was asymmetric; (iv) a putative olfactory space could be defined for the honeybee with functional group and carbon-chain length as inner dimensions; (v) perceptual distances in such a space correlate well with physiological distances determined from optophysiological recordings of antennal lobe activity. We conclude that functional group and carbon-chain length are inner dimensions of the honeybee olfactory space and that neural activity in the antennal lobe reflects the perceptual quality of odours. PMID:15736975

2005-01-01

341

Perceptual Consequences of “Hidden” Hearing Loss  

PubMed Central

Dramatic results from recent animal experiments show that noise exposure can cause a selective loss of high-threshold auditory nerve fibers without affecting absolute sensitivity permanently. This cochlear neuropathy has been described as hidden hearing loss, as it is not thought to be detectable using standard measures of audiometric threshold. It is possible that hidden hearing loss is a common condition in humans and may underlie some of the perceptual deficits experienced by people with clinically normal hearing. There is some evidence that a history of noise exposure is associated with difficulties in speech discrimination and temporal processing, even in the absence of any audiometric loss. There is also evidence that the tinnitus experienced by listeners with clinically normal hearing is associated with cochlear neuropathy, as measured using Wave I of the auditory brainstem response. To date, however, there has been no direct link made between noise exposure, cochlear neuropathy, and perceptual difficulties. Animal experiments also reveal that the aging process itself, in the absence of significant noise exposure, is associated with loss of auditory nerve fibers. Evidence from human temporal bone studies and auditory brainstem response measures suggests that this form of hidden loss is common in humans and may have perceptual consequences, in particular, regarding the coding of the temporal aspects of sounds. Hidden hearing loss is potentially a major health issue, and investigations are ongoing to identify the causes and consequences of this troubling condition. PMID:25204468

Barker, Daphne; Prendergast, Garreth

2014-01-01

342

Tangential Speed  

NSDL National Science Digital Library

This lab is purely a thought experiment. Although students are given an introduction to angular speed and tangential speed, they will discover the relationship between the two in this activity. The lab is an inquiry activity in that students do not know t

Horton, Michael

2009-05-30

343

Associations between AQT Processing Speed and Neuropsychological Tests in Neuropsychiatric Patients  

Microsoft Academic Search

Associations between A Quick Test of Cognitive Speed (AQT) perceptual and cognitive speed and neuropsychological tests, including the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), Mini Mental State Examination (MMSE), and the Trail Making Test (TMT), were evaluated in 41 neuropsychiatric patients. Neuropsychological and neurological tests, including CT scan, were administered to all of the patients. AQT was also administered to

Niels Peter Nielsen; Roland Ringström; Elisabeth H. Wiig; Lennart Minthon

2007-01-01

344

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

PubMed

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. PMID:23053842

Furley, Philip; Memmert, Daniel; Schmid, Simone

2013-03-01

345

Attention to memory and the environment: functional specialization and dynamic competition in human posterior parietal cortex  

PubMed Central

Posterior parietal cortex has been traditionally associated with perceptual attention and sensory-motor processing, but recent studies also indicate a potential role in episodic memory retrieval. Here, we developed a new paradigm to isolate top-down attention-related activity directed to either memory or perceptual information. We demonstrated a robust topographic separation in human posterior parietal cortex associated with searching for task-relevant information in episodic memory or in the environment. Control analyses confirmed that this difference was not dependent on differences in sensory stimulation or eye movements across tasks. Notably, we observed in memory- and perception-related regions a mechanism of reciprocal dynamic competition that was related to behavioral performance. These results provide the first evidence for a double dissociation between parietal networks involved in top-down attention to memory and the environment and support the idea of neural competition between perception and memory. PMID:20573892

Sestieri, Carlo; Shulman, Gordon L.; Corbetta, Maurizio

2010-01-01

346

Memory structures that subserve sentence comprehension  

Microsoft Academic Search

Measures of the speed and accuracy of processing sentences with nonadjacent dependencies derived from the response-signal speed-accuracy tradeoff procedure were used to examine the nature of the memory system that underlies sentence comprehension. Three experiments with different sentence structures demonstrated that the accuracy of processing a dependency decreased as more material was interpolated between nonadjacent constituents. However, processing speed was

Brian McElree; Stephani Foraker; Lisbeth Dyer

2003-01-01

347

Perceptual load corresponds with factors known to influence visual search  

PubMed Central

One account of the early versus late selection debate in attention proposes that perceptual load determines the locus of selection. Attention selects stimuli at a late processing level under low-load conditions but selects stimuli at an early level under high-load conditions. Despite the successes of perceptual load theory, a non-circular definition of perceptual load remains elusive. We investigated the factors that influence perceptual load by using manipulations that have been studied extensively in visual search, namely target-distractor similarity and distractor-distractor similarity. Consistent with previous work, search was most efficient when targets and distractors were dissimilar and the displays contained homogeneous distractors; search became less efficient when target-distractor similarity increased irrespective of display heterogeneity. Importantly, we used these same stimuli in a typical perceptual load task that measured attentional spill-over to a task-irrelevant flanker. We found a strong correspondence between search efficiency and perceptual load; stimuli that generated efficient searches produced flanker interference effects, suggesting that such displays involved low perceptual load. Flanker interference effects were reduced in displays that produced less efficient searches. Furthermore, our results demonstrate that search difficulty, as measured by search intercept, has little bearing on perceptual load. These results suggest that perceptual load might be defined in part by well-characterized, continuous factors that influence visual search. PMID:23398258

Roper, Zachary J. J.; Cosman, Joshua D.; Vecera, Shaun P.

2014-01-01

348

[Neural correlates of perceptual decisions: the role of the ventral premotor cortex].  

PubMed

Although the premotor cortex was initially viewed as the substrate of pure motor functions, it was soon realized that this cortical region is also involved in higher order cognitive processes. By using behavioral tasks together with electrophysiological recordings it has been possible to advance in our understanding on the functional role of this area. Given its pattern of connections, the premotor ventral cortex is well suited to participate in perceptual decisions, in which sensory information is combined with knowledge on previous outcomes and expectancies to reach a behavioral choice. The neuronal correlates of the decision process have been described in several cortical areas of primates. In this work we describe our experimental results showing that different stages or elements of perceptual decisions are encoded in the firing rate of premotor ventral cortex neurons. This provides compelling evidence suggesting that this area is involved in the use of sensory evidence -maintained in working memory or retrieved from long-term memory- to reach a decision. Furthermore, after the behavioral response the same neurons convey all the information needed to evaluate the outcome of the choice. This suggests that the premotor ventral cortex could participate in shaping future behavior as a result of this evaluation. PMID:24777768

Pardo-Vázquez, José L; Acuña, Carlos

2014-05-01

349

High-Speed Scanning in Human Memory  

Microsoft Academic Search

When subjects judge whether a test symbol is contained in a short memorized sequence of symbols, their mean reaction-time increases linearly with the length of the sequence. The linearity and slope of the function imply the existence of an internal serial-comparison process whose average rate is between 25 and 30 symbols per second.

Saul Sternberg

1966-01-01

350

Heavy Drinking in Midlife Speeds Memory Loss  

MedlinePLUS

... Expert Reviewed News - FREE Choose a Category Caregiving Diet & Exercise Alzheimer's Research Long Term Planning Alzheimer's News Recent News ... study shows. The study raises questions about whether patients with Alzheimer’s may … Continue reading ? Translate to: Arabic Bulgarian Catalan ...

351

Alterations in Physiological and Perceptual Variables during Exhaustive Endurance Work while Wearing a Pressure-Demand Respirator  

Microsoft Academic Search

The purpose of this investigation was to describe the time course of changes in physiological and perceptual variables during exhaustive endurance work with and without an air-supplied, full-facepicce, pressure-demand respirator. Thirty-eight healthy subjects(24 to 51 years of age) volunteered for this study. Treadmill speed was set at 5.5?kph (3.4?mph) and elevation was set at a level calculated to elicit 70%

JUDY R. WILSON; PETER B. RAVEN; STEVEN A. ZINKGRAF; WILLIAM P. MORGAN; ALLEN W. JACKSON

1989-01-01

352

Dysphonia subsequent to severe traumatic brain injury: comparative perceptual, acoustic and electroglottographic analyses.  

PubMed

We tested the applicability of the Goettinger Hoarseness Diagram (GHD) for quantitative evaluation of voice disorders after severe traumatic brain injury (TBI) and compared the obtained data with those from established voice analysis systems such as the Multi-Dimensional Voice Program (MDVP), electroglottography (EGG) and perceptual ratings using sustained vowel productions from 10 patients with TBI dysarthrophonia at late stages postinjury and of 10 healthy control speakers. Statistical analyses revealed significant intergroup differences with respect to various acoustic and perceptual measures, i.e., irregularity component, noise component, noise-to-harmonic ratio, shimmer, jitter, roughness, creakiness, strained-strangledness, hypernasality. By contrast, the considered EGG estimates, i.e., open quotient and speed quotient, did not allow for separation of patients and controls. In addition, the two GHD components exhibited close correlations to perceived roughness and creakiness, on the one hand, and breathiness and, to some degree, nasality, on the other, whereas the MDVP parameters failed to differentiate between these two perceptual modes of phonation. PMID:11721139

Jaeger, M; Fröhlich, M; Hertrich, I; Ackermann, H; Schönle, P W

2001-01-01

353

Perceptual basis of redundancy gains in visual pop-out search.  

PubMed

The redundant-signals effect (RSE) refers to a speed-up of RT when the response is triggered by two, rather than just one, response-relevant target elements. Although there is agreement that in the visual modality RSEs observed with dimensionally redundant signals originating from the same location are generated by coactive processing architectures, there has been a debate as to the exact stage(s)--preattentive versus postselective--of processing at which coactivation arises. To determine the origin(s) of redundancy gains in visual pop-out search, the present study combined mental chronometry with electrophysiological markers that reflect purely preattentive perceptual (posterior-contralateral negativity [PCN]), preattentive and postselective perceptual plus response selection-related (stimulus-locked lateralized readiness potential [LRP]), or purely response production-related processes (response-locked LRP). As expected, there was an RSE on target detection RTs, with evidence for coactivation. At the electrophysiological level, this pattern was mirrored by an RSE in PCN latencies, whereas stimulus-locked LRP latencies showed no RSE over and above the PCN effect. Also, there was no RSE on the response-locked LRPs. This pattern demonstrates a major contribution of preattentive perceptual processing stages to the RSE in visual pop-out search, consistent with parallel-coactive coding of target signals in multiple visual dimensions [Müller, H. J., Heller, D., & Ziegler, J. Visual search for singleton feature targets within and across feature dimensions. PMID:20044891

Töllner, Thomas; Zehetleitner, Michael; Krummenacher, Joseph; Müller, Hermann J

2011-01-01

354

The Role of Textured Material in Supporting Perceptual-Motor Functions  

PubMed Central

Simple deformation of the skin surface with textured materials can improve human perceptual-motor performance. The implications of these findings are inexpensive, adaptable and easily integrated clothing, equipment and tools for improving perceptual-motor functionality. However, some clarification is needed because mixed results have been reported in the literature, highlighting positive, absent and/or negative effects of added texture on measures of perceptual-motor performance. Therefore the aim of this study was to evaluate the efficacy of textured materials for enhancing perceptual-motor functionality. The systematic review uncovered two variables suitable for sub-group analysis within and between studies: participant age (groupings were 18–51 years and 64.7–79.4 years) and experimental task (upright balance and walking). Evaluation of studies that observed texture effects during upright balance tasks, uncovered two additional candidate sub-groups for future work: vision (eyes open and eyes closed) and stability (stable and unstable). Meta-analysis (random effects) revealed that young participants improve performance by a small to moderate amount in upright balance tasks with added texture (SMD?=?0.28, 95%CI?=?0.46–0.09, Z?=?2.99, P?=?0.001; Tau2?=?0.02; Chi2?=?9.87, df?=?6, P?=?0.13; I2?=?39.22). Significant heterogeneity was found in, the overall effect of texture: Tau2?=?0.13; Chi2?=?130.71, df?=?26, P<0.0001; I2?=?85.98%, pooled samples in upright balance tasks: Tau2?=?0.09; Chi2?=?101.57, df?=?13, P<0.001; I2?=?72.67%, and in elderly in upright balance tasks: Tau2?=?0.16; Chi2?=?39.42, df?=?5, P<0.001; I2?=?83.05%. No effect was shown for walking tasks: Tau2?=?0.00; Chi2?=?3.45, df?=?4, P?=?0.27, I2?=?22.99%. Data provides unequivocal support for utilizing textured materials in young healthy populations for improving perceptual-motor performance. Future research is needed in young healthy populations under conditions where visual and proprioceptive information is challenged, as in high-speed movements, or where use of equipment mediates the performer-environment interaction or where dysfunctional information sources ‘compete’ for attention. In elderly and ailing populations data suggests further research is required to better understand contexts where texture can facilitate improved perceptual-motor performance. PMID:23565232

Orth, Dominic; Davids, Keith; Wheat, Jon; Seifert, Ludovic; Liukkonen, Jarmo; Jaakkola, Timo; Ashford, Derek; Kerr, Graham

2013-01-01

355

Evidence from auditory and visual event-related potential (ERP) studies of deviance detection (MMN and vMMN) linking predictive coding theories and perceptual object representations.  

PubMed

Predictive coding theories posit that the perceptual system is structured as a hierarchically organized set of generative models with increasingly general models at higher levels. The difference between model predictions and the actual input (prediction error) drives model selection and adaptation processes minimizing the prediction error. Event-related brain potentials elicited by sensory deviance are thought to reflect the processing of prediction error at an intermediate level in the hierarchy. We review evidence from auditory and visual studies of deviance detection suggesting that the memory representations inferred from these studies meet the criteria set for perceptual object representations. Based on this evidence we then argue that these perceptual object representations are closely related to the generative models assumed by predictive coding theories. PMID:22047947

Winkler, István; Czigler, István

2012-02-01

356

Exploring Perceptual Skills in Children with Autism Spectrum Disorders: From Target Detection to Dynamic Perceptual Discrimination  

ERIC Educational Resources Information Center

Perceptual processing in autism is associated with both "strengths" and "weaknesses" but within a literature that varies widely in terms of the assessments used. We report data from 12 children with autism spectrum disorders (ASD) and 12 age and IQ matched neurotypical controls tested on a set of tasks using the same stimuli…

Miller, Louisa; McGonigle-Chalmers, Maggie

2014-01-01

357

Prolonged perceptual learning of positional acuity in adult amblyopia: perceptual template retuning dynamics.  

PubMed

Amblyopia is a developmental abnormality that results in physiological alterations in the visual cortex and impairs form vision. It is often successfully treated by patching the sound eye in infants and young children, but is generally considered to be untreatable in adults. However, a number of recent studies suggest that repetitive practice of a visual task using the amblyopic eye results in improved performance in both children and adults with amblyopia. These perceptual learning studies have used relatively brief periods of practice; however, clinical studies have shown that the time-constant for successful patching is long. The time-constant for perceptual learning in amblyopia is still unknown. Here we show that the time-constant for perceptual learning depends on the degree of amblyopia. Severe amblyopia requires >50 h (approximately equal to 35,000 trials) to reach plateau, yielding as much as a five-fold improvement in performance at a rate of approximately equal to 1.5%/h. There is significant transfer of learning from the amblyopic to the dominant eye, suggesting that the learning reflects alterations in higher decision stages of processing. Using a reverse correlation technique, we document, for the first time, a dynamic retuning of the amblyopic perceptual decision template and a substantial reduction in internal spatial distortion. These results show that the mature amblyopic brain is surprisingly malleable, and point to more intensive treatment methods for amblyopia. PMID:19109504

Li, Roger W; Klein, Stanley A; Levi, Dennis M

2008-12-24

358

Perceptual consequences of disrupted auditory nerve activity.  

PubMed

Perceptual consequences of disrupted auditory nerve activity were systematically studied in 21 subjects who had been clinically diagnosed with auditory neuropathy (AN), a recently defined disorder characterized by normal outer hair cell function but disrupted auditory nerve function. Neurological and electrophysical evidence suggests that disrupted auditory nerve activity is due to desynchronized or reduced neural activity or both. Psychophysical measures showed that the disrupted neural activity has minimal effects on intensity-related perception, such as loudness discrimination, pitch discrimination at high frequencies, and sound localization using interaural level differences. In contrast, the disrupted neural activity significantly impairs timing related perception, such as pitch discrimination at low frequencies, temporal integration, gap detection, temporal modulation detection, backward and forward masking, signal detection in noise, binaural beats, and sound localization using interaural time differences. These perceptual consequences are the opposite of what is typically observed in cochlear-impaired subjects who have impaired intensity perception but relatively normal temporal processing after taking their impaired intensity perception into account. These differences in perceptual consequences between auditory neuropathy and cochlear damage suggest the use of different neural codes in auditory perception: a suboptimal spike count code for intensity processing, a synchronized spike code for temporal processing, and a duplex code for frequency processing. We also proposed two underlying physiological models based on desynchronized and reduced discharge in the auditory nerve to successfully account for the observed neurological and behavioral data. These methods and measures cannot differentiate between these two AN models, but future studies using electric stimulation of the auditory nerve via a cochlear implant might. These results not only show the unique contribution of neural synchrony to sensory perception but also provide guidance for translational research in terms of better diagnosis and management of human communication disorders. PMID:15615831

Zeng, Fan-Gang; Kong, Ying-Yee; Michalewski, Henry J; Starr, Arnold

2005-06-01

359

A perceptual map for understanding concern about unsafe driving behaviours.  

PubMed

The objective of this paper is to develop a model that can help explain the public's level of concern associated with six dangerous driving behaviours (drinking and driving, speeding, distracted driving, using a cell phone while driving, fatigued or drowsy driving, and using illegal drugs while driving). Understanding the genesis of concern can be useful in addressing it and leveraging it to improve safe driving. Building on a risk perception model that was developed previously, the study investigated the relationship between the level of concern about the unsafe driving behaviours and the perceived level of concern of others about the dangerous driving behaviours, the perception of the prevalence of the dangerous driving behaviours, the perception of the level of risk imposed by these dangerous driving behaviours, and the perception of the severity of injuries that can result from them. Data from two independent samples were modeled using multidimensional scaling and logistic regression analysis. Both samples come from telephone surveys; one was administered to a random sample of 750 drivers in the province of Ontario, Canada in November 2006, the other to a random sample of 1201 drivers across Canada in September 2006. Two dimensions in particular were found to fit the data well: perceived risk and the perceived level of concern of others. The results from these analyses are summarized using a perceptual map. The relevance of such a map is illustrated by explaining the factors that impact levels of concern regarding several of the unsafe driving behaviours. PMID:18760094

Vanlaar, Ward; Simpson, Herb; Robertson, Robyn

2008-09-01

360

Perceptual separability of featural and configural information in congenital prosopagnosia.  

PubMed

The deficit in face recognition in individuals with prosopagnosia has often been attributed to an underlying impairment in holistic processing. Exactly what constitutes holistic processing has remained controversial, however. Here, we compare how configural information and featural information interact during face processing in a group of individuals with congenital prosopagnosia (CP) and matched controls. We adopted Amishav and Kimchi's version of Garner's speeded classification task, in which observers classify upright faces based on configural (intereyes and nose-mouth spacing) or featural (shape of eyes, nose, and mouth) information while the other dimension remains constant or varied randomly. We replicated the finding that normal observers evince symmetric Garner interference--failure to selectively attend to features without being influenced by irrelevant variation in configuration, and vice versa--indicating that featural and configural information are integral in normal face processing. In contrast, the CPs showed no Garner interference: They were able to attend to configural information without interference from irrelevant variation in featural information, and they were able to attend to featural information without interference from irrelevant variation in configural information. The absence of Garner interference in CP provides strong evidence that featural information and configural information are perceptually separable in CP's face processing. These findings indicate that CPs do not perceive faces holistically; rather, they process featural and configural information independently. PMID:23428081

Kimchi, Ruth; Behrmann, Marlene; Avidan, Galia; Amishav, Rama

2012-01-01

361

Ongoing behavior predicts perceptual report of interval duration  

PubMed Central

The ability to estimate the passage of time is essential for adaptive behavior in complex environments. Yet, it is not known how the brain encodes time over the durations necessary to explain animal behavior. Under temporally structured reinforcement schedules, animals tend to develop temporally structured behavior, and interval timing has been suggested to be accomplished by learning sequences of behavioral states. If this is true, trial to trial fluctuations in behavioral sequences should be predictive of fluctuations in time estimation. We trained rodents in an duration categorization task while continuously monitoring their behavior with a high speed camera. Animals developed highly reproducible behavioral sequences during the interval being timed. Moreover, those sequences were often predictive of perceptual report from early in the trial, providing support to the idea that animals may use learned behavioral patterns to estimate the duration of time intervals. To better resolve the issue, we propose that continuous and simultaneous behavioral and neural monitoring will enable identification of neural activity related to time perception that is not explained by ongoing behavior. PMID:24672473

Gouvea, Thiago S.; Monteiro, Tiago; Soares, Sofia; Atallah, Bassam V.; Paton, Joseph J.

2014-01-01

362

JPEG 2000 Encoding with Perceptual Distortion Control  

NASA Technical Reports Server (NTRS)

An alternative approach has been devised for encoding image data in compliance with JPEG 2000, the most recent still-image data-compression standard of the Joint Photographic Experts Group. Heretofore, JPEG 2000 encoding has been implemented by several related schemes classified as rate-based distortion-minimization encoding. In each of these schemes, the end user specifies a desired bit rate and the encoding algorithm strives to attain that rate while minimizing a mean squared error (MSE). While rate-based distortion minimization is appropriate for transmitting data over a limited-bandwidth channel, it is not the best approach for applications in which the perceptual quality of reconstructed images is a major consideration. A better approach for such applications is the present alternative one, denoted perceptual distortion control, in which the encoding algorithm strives to compress data to the lowest bit rate that yields at least a specified level of perceptual image quality. Some additional background information on JPEG 2000 is prerequisite to a meaningful summary of JPEG encoding with perceptual distortion control. The JPEG 2000 encoding process includes two subprocesses known as tier-1 and tier-2 coding. In order to minimize the MSE for the desired bit rate, a rate-distortion- optimization subprocess is introduced between the tier-1 and tier-2 subprocesses. In tier-1 coding, each coding block is independently bit-plane coded from the most-significant-bit (MSB) plane to the least-significant-bit (LSB) plane, using three coding passes (except for the MSB plane, which is coded using only one "clean up" coding pass). For M bit planes, this subprocess involves a total number of (3M - 2) coding passes. An embedded bit stream is then generated for each coding block. Information on the reduction in distortion and the increase in the bit rate associated with each coding pass is collected. This information is then used in a rate-control procedure to determine the contribution of each coding block to the output compressed bit stream.

Watson, Andrew B.; Liu, Zhen; Karam, Lina J.

2008-01-01

363

Perceptual-components architecture for digital video  

NASA Technical Reports Server (NTRS)

A perceptual-components architecture for digital video partitions the image stream into signal components in a manner analogous to that used in the human visual system. These components consist of achromatic and opponent color channels, divided into static and motion channels, further divided into bands of particular spatial frequency and orientation. Bits are allocated to an individual band in accord with visual sensitivity to that band and in accord with the properties of visual masking. This architecture is argued to have desirable features such as efficiency, error tolerance, scalability, device independence, and extensibility.

Watson, Andrew B.

1990-01-01

364

Perceptual Optimization of DCT Color Quantization Matrices  

NASA Technical Reports Server (NTRS)

Many image compression schemes employ a block Discrete Cosine Transform (DCT) and uniform quantization. Acceptable rate/distortion performance depends upon proper design of the quantization matrix. In previous work, we showed how to use a model of the visibility of DCT basis functions to design quantization matrices for arbitrary display resolutions and color spaces. Subsequently, we showed how to optimize greyscale quantization matrices for individual images, for optimal rate/perceptual distortion performance. Here we describe extensions of this optimization algorithm to color images.

Watson, Andrew B.; Statler, Irving C. (Technical Monitor)

1994-01-01

365

Perceptual user interface in virtual shopping environment  

NASA Astrophysics Data System (ADS)

In this paper we present our effort towards the goal of perceptual user interface for major interaction tasks, such as navigation/travel, selection/picking and personal data access, for virtual shopping. A set of 3-D navigation devices, vision-based pointing and personal access system are mainly discussed. The motivation and design principles behind these interfaces are also described. A prototype integration solution, which bring these devices together in virtual shopping environment, is given. These interfaces and interaction devices have been implemented and tested for evaluation.

Geng, Weidong; Strauss, Wolfgang S. L.; Fleischmann, Monika; Elistratov, Vladimir; Kulessa, Thomas; Kolesnik, Marina

2003-04-01

366

Differentiating amodal familiarity from modality-specific memory processes: An ERP study  

PubMed Central

Distinct event-related potential effects have been related to familiarity and recollection processes underlying recognition memory. Familiarity has been conceptualized as similar either to perceptual priming mechanisms supporting implicit memory or to amodal global-matching processes that should show little sensitivity to perceptual variables. The present experiment manipulated the study modality of words (auditory, visual) that were visually tested for recognition memory. The mid-frontal (300–500 ms) old/new effect often attributed to familiarity was not affected by study modality, so it appears related to an amodal familiarity process. An earlier (176–260 ms) fronto-polar old/new effect was perceptually specific in that it was observed only following visual study. The parietal old/new effect (400–800 ms), often attributed to recollection, was similar following both visual and auditory study. Temporal-spatial PCA clarified the separability of these effects. PMID:14986851

DIEN, JOSEPH

2005-01-01

367

Drawing from memory: hand-eye coordination at multiple scales.  

PubMed

Eyes move to gather visual information for the purpose of guiding behavior. This guidance takes the form of perceptual-motor interactions on short timescales for behaviors like locomotion and hand-eye coordination. More complex behaviors require perceptual-motor interactions on longer timescales mediated by memory, such as navigation, or designing and building artifacts. In the present study, the task of sketching images of natural scenes from memory was used to examine and compare perceptual-motor interactions on shorter and longer timescales. Eye and pen trajectories were found to be coordinated in time on shorter timescales during drawing, and also on longer timescales spanning study and drawing periods. The latter type of coordination was found by developing a purely spatial analysis that yielded measures of similarity between images, eye trajectories, and pen trajectories. These results challenge the notion that coordination only unfolds on short timescales. Rather, the task of drawing from memory evokes perceptual-motor encodings of visual images that preserve coarse-grained spatial information over relatively long timescales as well. PMID:23554894

Huette, Stephanie; Kello, Christopher T; Rhodes, Theo; Spivey, Michael J

2013-01-01

368

The Role of Perceptual Load in Object Recognition  

ERIC Educational Resources Information Center

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…

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

2009-01-01

369

Toward a Perceptual Space for Gloss Sony Pictures Imageworks  

E-print Network

103 Toward a Perceptual Space for Gloss JOSH WILLS Sony Pictures Imageworks SAMEER AGARWAL of these bidirectional reflectance distribution functions (BRDFs). The embedding is validated by correlating it with nine gloss dimensions, fitted parameters of seven analytical BRDF models, and a perceptual parameterization

Jaffe, Jules

370

Teaching social perceptual skills to students with learning disabilities  

Microsoft Academic Search

We investigated the effects of descriptive feedback and reinforcement on the acquisition and exhibition of social perceptual skills in three students with identified learning disabilities and social perceptual deficits. The students rated their teacher's affect based on six emotions, and received feedback regarding the accuracy of their ratings plus reinforcement for accurate ratings. Descriptive feedback and reinforcement resulted in a

Andrew B. Sandier; Jane Y. Murdock; Elizabeth Dofny; Paul J. Gerber

1991-01-01

371

Perceptual Processing Development: Its Relation to Learning Disabilities. Section I.  

ERIC Educational Resources Information Center

Presented is a developmental concept of perceptual processing as related to learning disabilities in young children. Learning is seen to involve the interaction of cognitive developmental stages at the preverbal, verbal, and postverbal levels with learning disabilities seen to be due to perceptual handicaps. A model is offered which posits a…

Wepman, Joseph M.

372

Perceptual evidence for saccadic updating of color stimuli  

E-print Network

Perceptual evidence for saccadic updating of color stimuli Department of Physics, Neurophysics eye movements. So far, there is only limited evidence for similar mechanisms that support perceptual present study, we investigated whether color stimuli presented before a saccade affected the perception

Crawford, Doug

373

Semantic and Perceptual Priming: How Similar Are the Underlying Mechanisms?  

Microsoft Academic Search

Both semantic priming and perceptual priming consist of facilitation of the identification of primed stimuli and inhibition of the identification of nonprimed stimuli. The similarities between the two phenomena suggest that a common attentional mechanism underlies both, and this has been explicitly proposed by several attention theorists. In this article it is argued that the phenomena of semantic and perceptual

Martha J. Farah

1989-01-01

374

Effect of Scenario on Perceptual Sensitivity to Errors in Animation  

E-print Network

15 Effect of Scenario on Perceptual Sensitivity to Errors in Animation PAUL S. A. REITSMA and CAROL O'SULLIVAN Trinity College Dublin A deeper understanding of what makes animation perceptually plausible would benefit a number of applications, such as approx- imate collision detection and goal

O'Sullivan, Carol

375

What Goes with What? Development of Perceptual Grouping in Infancy  

Microsoft Academic Search

Pattern perception and organization provide the representations that form the basic processing units in the visual cognition system of adults. This chapter will highlight a line of research investigating the origins and development of such perceptual organization abilities in infants. In particular, the chapter will describe the major theoretical positions on the development of perceptual unit formation and review empirical

Paul C. Quinn; Ramesh S. Bhatt; Angela Hayden

2008-01-01

376

Investigating Auditory Reverse Hierarchy Theory (RHT) in Perception and Perceptual  

E-print Network

Investigating Auditory Reverse Hierarchy Theory (RHT) in Perception and Perceptual Learning of the Hebrew University February/2009 #12;Investigating Auditory Reverse Hierarchy Theory (RHT) in Perception Reverse Hierarchy Theory (RHT) in Perception and Perceptual Learning Processes In the past few decades

377

Cortical plasticity in perceptual learning demonstrated by transcranial magnetic stimulation  

Microsoft Academic Search

Performance on a wide range of perceptual tasks improves with practice. Most accounts of perceptual learning are concerned with changes in neuronal sensitivity or changes in the way a stimulus is represented. Another possibility is that different areas of the brain are involved in performing a task during and after learning it. Here, we demonstrate that the right parietal cortex

Vincent Walsh; Elisabeth Ashbridge; Alan Cowey

1998-01-01

378

Perceptual Learning: 12-Month-Olds' Discrimination of Monkey Faces  

ERIC Educational Resources Information Center

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…

Fair, Joseph; Flom, Ross; Jones, Jacob; Martin, Justin

2012-01-01

379

Effect of Scenario on Perceptual Sensitivity to Errors in Animation  

E-print Network

-Dimensional Graphics and Realism-- Animation General Terms: Experimentation, Human Factors, Measurement Additional KeyEffect of Scenario on Perceptual Sensitivity to Errors in Animation PAUL S. A. REITSMA and CAROL O'SULLIVAN Trinity College Dublin A deeper understanding of what makes animation perceptually plausible would benefit

Treuille, Adrien

380

Selective Attention to Perceptual Dimensions and Switching between Dimensions  

ERIC Educational Resources Information Center

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…

Meiran, Nachshon; Dimov, Eduard; Ganel, Tzvi

2013-01-01

381

Neurological Evidence Linguistic Processes Precede Perceptual Simulation in Conceptual Processing  

PubMed Central

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

Louwerse, Max; Hutchinson, Sterling

2012-01-01

382

Changes in color appearance caused by perceptual grouping  

Microsoft Academic Search

How is chromatic induction affected by perceptual grouping? Chromatic induction has been studied extensively, as has grouping, but only a small number of experiments have connected them. Even fewer reports go beyond weakly controlled qualitative observations. We report here a new and substantial color shift caused by perceptual grouping: a shift in appearance due to chromatic induction in one part

SHERRY X. XIAN; STEVEN K. SHEVELL

2004-01-01

383

Effects of categorization and discrimination training on auditory perceptual space  

E-print Network

effects for voice onset time VOT distinctions be- tween /$/ and /#/ Liberman et al., 1961b and between to this warping as a ``perceptual magnet effect,'' thus distinguishing it from cat- egorical perception. RoughlyEffects of categorization and discrimination training on auditory perceptual space Frank H

Shinn-Cunningham, Barbara G.

384

Perceptual Organization as a Foundation for Intelfigent Sketch Editing  

Microsoft Academic Search

This paper discusses the design of intelligent sketch editing tools exploiting intermediate levels of visual interpretation known as Perceptual Organization. Sketches are much more than an accumulation of strokes: they convey information largely through spatial configurations and patterns among markings. We propose that the detection of this visual structure, based on the principles of Perceptual Organization, will make sketch editing

Eric Saund; James Mahoney; David Fleet; Dan Lamer; Edward Lank

2002-01-01

385

Psychophysical indices of perceptual functioning in dyslexia: A psychometric analysis  

E-print Network

Psychophysical indices of perceptual functioning in dyslexia: A psychometric analysis Steve M dyslexia to visual and/or auditory perceptual deficits. This theory derives from group differences between individuals with dyslexia and controls on a range of psychophysical tasks, but there is substantial variation

Nottingham, University of

386

Document perceptual quality ground truth creation Vincent Rabeux  

E-print Network

Document perceptual quality ground truth creation Vincent Rabeux LaBRI Bordeaux, France rabeux method for document perceptual quality ground truth creation. This type of ground truth gives a quality of these ground truths takes a very long time. In this article, we present a new methodology to create this kind

Paris-Sud XI, Université de

387

Memory for details with self-referencing.  

PubMed

Self-referencing benefits item memory, but little is known about the ways in which referencing the self affects memory for details. Experiment 1 assessed whether the effects of self-referencing operate only at the item, or general, level or whether they also enhance memory for specific visual details of objects. Participants incidentally encoded objects by making judgements in reference to the self, a close other (one's mother), or a familiar other (Bill Clinton). Results indicate that referencing the self or a close other enhances both specific and general memory. Experiments 2 and 3 assessed verbal memory for source in a task that relied on distinguishing between different mental operations (internal sources). The results indicate that self-referencing disproportionately enhances source memory, relative to conditions referencing other people, semantic, or perceptual information. We conclude that self-referencing not only enhances specific memory for both visual and verbal information, but can also disproportionately improve memory for specific internal source details. PMID:22092106

Serbun, Sarah J; Shih, Joanne Y; Gutchess, Angela H

2011-11-01

388

The perceptual responses to occluded exercise.  

PubMed

The purpose was to determine repetitions to failure and perceptual responses to exercise with and without occlusion. 15 subjects participated in a randomized crossover study of 3 trials. The first determined one repetition maximum (1RM) on the leg extension. Subjects were then assigned to an occlusion (OCC) or control (CON) group. After trial 2, subjects crossed over to the opposite trial. Knee wraps (KW) were placed around the upper thigh of each leg during OCC. Subjects completed 2 sets of leg extensions to failure at 30% 1RM, with 30 s rest between sets. Ratings of perceived exertion (RPE) and pain (P) were taken following each set. Data were analyzed using paired sample t-tests with an alpha level of 0.01. OCC repetitions were lower for the first and second set compared to CON (p=0.001). Total work completed was significantly lower with OCC compared to CON (p=0.001). OCC RPE were higher for both the first (p=0.01) and second set (p=0.003) compared to CON. P was not different following one set but was higher with OCC over CON following the second (p=0.009). In conclusion, KW provide an OCC stimulus allowing failure to occur sooner. However, the higher perceptual responses with OCC may limit its application to the highly motivated. PMID:21165798

Loenneke, J P; Balapur, A; Thrower, A D; Barnes, J T; Pujol, T J

2011-03-01

389

Referenceless perceptual fog density prediction model  

NASA Astrophysics Data System (ADS)

We propose a perceptual fog density prediction model based on natural scene statistics (NSS) and "fog aware" statistical features, which can predict the visibility in a foggy scene from a single image without reference to a corresponding fogless image, without side geographical camera information, without training on human-rated judgments, and without dependency on salient objects such as lane markings or traffic signs. The proposed fog density predictor only makes use of measurable deviations from statistical regularities observed in natural foggy and fog-free images. A fog aware collection of statistical features is derived from a corpus of foggy and fog-free images by using a space domain NSS model and observed characteristics of foggy images such as low contrast, faint color, and shifted intensity. The proposed model not only predicts perceptual fog density for the entire image but also provides a local fog density index for each patch. The predicted fog density of the model correlates well with the measured visibility in a foggy scene as measured by judgments taken in a human subjective study on a large foggy image database. As one application, the proposed model accurately evaluates the performance of defog algorithms designed to enhance the visibility of foggy images.

Choi, Lark Kwon; You, Jaehee; Bovik, Alan C.

2014-02-01

390

Flexible memory retrieval in bilingual 6-month-old infants.  

PubMed

Memory flexibility is a hallmark of the human memory system. As indexed by generalization between perceptually dissimilar objects, memory flexibility develops gradually during infancy. A recent study has found a bilingual advantage in memory generalization at 18 months of age [Brito and Barr [2012] Developmental Science, 15, 812-816], and the present study examines when this advantage may first emerge. In the current study, bilingual 6-month-olds were more likely than monolinguals to generalize to a puppet that differed in two features (shape and color) than monolingual 6-month-olds. When challenged with a less complex change, two puppets that differed only in one feature--color, monolingual 6-month-olds were also able to generalize. These findings demonstrate early emerging differences in memory generalization in bilingual infants, and have important implications for our understanding of how early environmental variations shape the trajectory of memory development. PMID:24318980

Brito, Natalie; Barr, Rachel

2014-07-01

391

Individual differences in false memory from misinformation: cognitive factors.  

PubMed

This research investigated the cognitive correlates of false memories that are induced by the misinformation paradigm. A large sample of Chinese college students (N=436) participated in a misinformation procedure and also took a battery of cognitive tests. Results revealed sizable and systematic individual differences in false memory arising from exposure to misinformation. False memories were significantly and negatively correlated with measures of intelligence (measured with Raven's Advanced Progressive Matrices and Wechsler Adult Intelligence Scale), perception (Motor-Free Visual Perception Test, Change Blindness, and Tone Discrimination), memory (Wechsler Memory Scales and 2-back Working Memory tasks), and face judgement (Face Recognition and Facial Expression Recognition). These findings suggest that people with relatively low intelligence and poor perceptual abilities might be more susceptible to the misinformation effect. PMID:20623420

Zhu, Bi; Chen, Chuansheng; Loftus, Elizabeth F; Lin, Chongde; He, Qinghua; Chen, Chunhui; Li, He; Xue, Gui; Lu, Zhonglin; Dong, Qi

2010-07-01

392

Tone Language Speakers and Musicians Share Enhanced Perceptual and Cognitive Abilities for Musical Pitch: Evidence for Bidirectionality between the Domains of Language and Music  

PubMed Central

Psychophysiological evidence suggests that music and language are intimately coupled such that experience/training in one domain can influence processing required in the other domain. While the influence of music on language processing is now well-documented, evidence of language-to-music effects have yet to be firmly established. Here, using a cross-sectional design, we compared the performance of musicians to that of tone-language (Cantonese) speakers on tasks of auditory pitch acuity, music perception, and general cognitive ability (e.g., fluid intelligence, working memory). While musicians demonstrated superior performance on all auditory measures, comparable perceptual enhancements were observed for Cantonese participants, relative to English-speaking nonmusicians. These results provide evidence that tone-language background is associated with higher auditory perceptual performance for music listening. Musicians and Cantonese speakers also showed superior working memory capacity relative to nonmusician controls, suggesting that in addition to basic perceptual enhancements, tone-language background and music training might also be associated with enhanced general cognitive abilities. Our findings support the notion that tone language speakers and musically trained individuals have higher performance than English-speaking listeners for the perceptual-cognitive processing necessary for basic auditory as well as complex music perception. These results illustrate bidirectional influences between the domains of music and language. PMID:23565267

Bidelman, Gavin M.; Hutka, Stefanie; Moreno, Sylvain

2013-01-01

393

Tone language speakers and musicians share enhanced perceptual and cognitive abilities for musical pitch: evidence for bidirectionality between the domains of language and music.  

PubMed

Psychophysiological evidence suggests that music and language are intimately coupled such that experience/training in one domain can influence processing required in the other domain. While the influence of music on language processing is now well-documented, evidence of language-to-music effects have yet to be firmly established. Here, using a cross-sectional design, we compared the performance of musicians to that of tone-language (Cantonese) speakers on tasks of auditory pitch acuity, music perception, and general cognitive ability (e.g., fluid intelligence, working memory). While musicians demonstrated superior performance on all auditory measures, comparable perceptual enhancements were observed for Cantonese participants, relative to English-speaking nonmusicians. These results provide evidence that tone-language background is associated with higher auditory perceptual performance for music listening. Musicians and Cantonese speakers also showed superior working memory capacity relative to nonmusician controls, suggesting that in addition to basic perceptual enhancements, tone-language background and music training might also be associated with enhanced general cognitive abilities. Our findings support the notion that tone language speakers and musically trained individuals have higher performance than English-speaking listeners for the perceptual-cognitive processing necessary for basic auditory as well as complex music perception. These results illustrate bidirectional influences between the domains of music and language. PMID:23565267

Bidelman, Gavin M; Hutka, Stefanie; Moreno, Sylvain

2013-01-01

394

Affecting speed and accuracy in perception.  

PubMed

An account of affective modulations in perceptual speed and accuracy (ASAP: Affecting Speed and Accuracy in Perception) is proposed and tested. This account assumes an emotion-induced inhibitory interaction between parallel channels in the visual system that modulates the onset latencies and response durations of visual signals. By trading off speed and accuracy between channels, this mechanism achieves (a) fast visuo-motor responding to course-grained information, and (b) accurate visuo-attentional selection of fine-grained information. ASAP gives a functional account of previously counterintuitive findings, and may be useful for explaining affective influences in both featural-level single-stimulus tasks and object-level multistimulus tasks. PMID:24853268

Bocanegra, Bruno R

2014-12-01

395

Optimizing linked perceptual class formation and transfer of function.  

PubMed

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 woman's voice would occasion the selection of any picture of the woman and vice versa. In addition, after learning to name the woman in the presence of one picture, that name would be uttered when presented with all of the images of the woman's face and all of the sounds of her voice. This study involved 15 participants and sought to (a) maximize the percentage of participants who formed linked perceptual classes, and (b) determine whether those classes acted as transfer networks, that is, whether the discriminative function of one class member would generalize to other members of the class and not to members of a different class. The rate of emergence of each linked perceptual class was maximized by establishing a single class-linking conditional relation between the clearest member of one class used as a sample stimulus and the most ambiguous member of the other class used as a comparison stimulus. Class formation was demonstrated using the serial and programmed presentation of A'-B' probes that consisted of untrained pairs of stimuli drawn from the A' and B' classes. Most participants showed immediate emergence of the two linked perceptual classes. The remaining participants showed delayed emergence following a second exposure to each originally error-producing probes. Once the linked perceptual classes had emerged, a differential response to a specific member of one perceptual class generalized mostly or completely to the other members of that linked class and rarely, if ever, to members of the other linked class. Thus, generalization did not depend on the specific class members that had been used for discrimination training. PMID:19794836

Fields, Lanny; Garruto, Michelle

2009-03-01

396

Is Statistical Learning Constrained by Lower Level Perceptual Organization?  

PubMed Central

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

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

2013-01-01

397

The Effect of a Perceptual-Motor Training Program Upon the Readiness and Perceptual Development of Culturally Disadvantaged Kindergarten Children.  

ERIC Educational Resources Information Center

As a part of a Title III project, a program was initiated to provide disadvantaged kindergarten children with planned perceptual-motor training exercises. This study investigates the effects of that program on the perceptual development and academic readiness of a group of 76 such children. The exercises, derived from the Kephart developmental…

Turner, Robert V.; Fisher, Maurice D.

398

1550 IEEE TRANSACTIONS ON FUZZY SYSTEMS, VOL. 16, NO. 6, DECEMBER 2008 Perceptual Reasoning for Perceptual Computing  

E-print Network

for Perceptual Computing Jerry M. Mendel, Life Fellow, IEEE, and Dongrui Wu, Student Member, IEEE Abstract subjective judgments using CWW was proposed by Mendel in 2001. It is called a Perceptual Computer (Per Angeles, CA 90089-2564 USA (e-mail: Mendel@sipi.usc.edu; dongruiw@ usc.edu). Digital Object Identifier 10

Mendle, Jerry M.

399

Cognitive memory.  

PubMed

Regarding the workings of the human mind, memory and pattern recognition seem to be intertwined. You generally do not have one without the other. Taking inspiration from life experience, a new form of computer memory has been devised. Certain conjectures about human memory are keys to the central idea. The design of a practical and useful "cognitive" memory system is contemplated, a memory system that may also serve as a model for many aspects of human memory. The new memory does not function like a computer memory where specific data is stored in specific numbered registers and retrieval is done by reading the contents of the specified memory register, or done by matching key words as with a document search. Incoming sensory data would be stored at the next available empty memory location, and indeed could be stored redundantly at several empty locations. The stored sensory data would neither have key words nor would it be located in known or specified memory locations. Sensory inputs concerning a single object or subject are stored together as patterns in a single "file folder" or "memory folder". When the contents of the folder are retrieved, sights, sounds, tactile feel, smell, etc., are obtained all at the same time. Retrieval would be initiated by a query or a prompt signal from a current set of sensory inputs or patterns. A search through the memory would be made to locate stored data that correlates with or relates to the prompt input. The search would be done by a retrieval system whose first stage makes use of autoassociative artificial neural networks and whose second stage relies on exhaustive search. Applications of cognitive memory systems have been made to visual aircraft identification, aircraft navigation, and human facial recognition. Concerning human memory, reasons are given why it is unlikely that long-term memory is stored in the synapses of the brain's neural networks. Reasons are given suggesting that long-term memory is stored in DNA or RNA. Neural networks are an important component of the human memory system, and their purpose is for information retrieval, not for information storage. The brain's neural networks are analog devices, subject to drift and unplanned change. Only with constant training is reliable action possible. Good training time is during sleep and while awake and making use of one's memory. A cognitive memory is a learning system. Learning involves storage of patterns or data in a cognitive memory. The learning process for cognitive memory is unsupervised, i.e. autonomous. PMID:23453302

Widrow, Bernard; Aragon, Juan Carlos

2013-05-01

400

Neural dynamics of perceptual order and context effects for variable-rate speech syllables.  

PubMed

How does the brain extract invariant properties of variable-rate speech? A neural model, called PHONET, is developed to explain aspects of this process and, along the way, data about perceptual context effects. For example, in consonant-vowel (CV) syllables, such as /ba/ and /wa/, an increase in the duration of the vowel can cause a switch in the percept of the preceding consonant from /w/ to /b/ (J.L. Miller & Liberman, 1979). The frequency extent of the initial formant transitions of fixed duration also influences the percept (Schwab, Sawusch, & Nusbaum, 1981). PHONET quantitatively simulates over 98% of the variance in these data, using a single set of parameters. The model also qualitatively explains many data about other perceptual context effects. In the model, C and V inputs are filtered by parallel auditory streams that respond preferentially to the transient and sustained properties of the acoustic signal before being stored in parallel working memories. A lateral inhibitory network of onset- and rate-sensitive cells in the transient channel extracts measures of frequency transition rate and extent. Greater activation of the transient stream can increase the processing rate in the sustained stream via a cross-stream automatic gain control interaction. The stored activities across these gain-controlled working memories provide a basis for rate-invariant perception, since the transient-to-sustained gain control tends to preserve the relative activities across the transient and sustained working memories as speech rate changes. Comparisons with alternative models tested suggest that the fit cannot be attributed to the simplicity of the data. Brain analogues of model cell types are described. PMID:10598464

Boardman, I; Grossberg, S; Myers, C; Cohen, M

1999-11-01

401

Virtual Memory  

Microsoft Academic Search

\\\\The need for automatic storage allocation arises from desires for program modularity, machine independence, and resource sharing. Virtual memory is an elegant way of achieving these objectives. In a virtual memory, the addresses a program may use to identify information are distinguished from the addresses the memory system uses to identify physical storage sites, and program-generated addresses are translated automatically

Peter J. Denning

1970-01-01

402

Working Memory  

Microsoft Academic Search

The term working memory refers to a brain system that provides temporary storage and manipulation of the information necessary for such complex cognitive tasks as language comprehension, learning, and reasoning. This definition has evolved from the concept of a unitary short-term memory system. Working memory has been found to require the simultaneous storage and processing of information. It can be

Alan Baddeley

1992-01-01

403

Features of autobiographical memory: theoretical and empirical issues in the measurement of flashbulb memory.  

PubMed

Flashbulb memories (FBMs) were defined by R. Brown and J. Kulik (1977) as vivid, detailed, and long-lasting memories for attributes of the reception context of public news. Unlike ordinary autobiographical memories, they are conceived as autobiographical formations that noticeably integrate specific perceptual details. The authors aimed to test a measurement model for FBMs as compared with event memory (EM) by hypothesizing that a categorical, rather than dimensional, approach would be more appropriate to account for FBM data. They submitted FBM and EM recollections from U.S. and European citizens concerning the terrorist attacks of September 11, 2001 to latent-trait model (LTM) and latent-class model (LCM) analyses. Results revealed that FBM data could be appropriately modeled through LCM, whereas for EM, LTM and LCM exhibited some inadequacy. The authors discuss implications for a theoretical account of FBMs. PMID:19350832

Curci, Antonietta; Lanciano, Tiziana

2009-04-01

404

Motor and Tactile-Perceptual Skill Differences Between Individuals with High-Functioning Autism and Typically Developing Individuals Ages 5 - 21  

PubMed Central

We examined motor and tactile-perceptual skills in individuals with high-functioning autism (IHFA) and matched typically developing individuals (TDI) ages 5 – 21 years. Grip strength, motor speed and coordination were impaired in IHFA compared to matched TDI, and the differences between groups varied with age. Although tactile-perceptual skills of IHFA were impaired compared to TDI on several measures, impairments were statistically and clinically significant only for stereognosis. Motor and tactile-perceptual skills should be assessed in children with IHFA and intervention should begin early because these skills are essential to school performance. Impairments in coordination and stereognosis suggest a broad though selective under-development of the circuitry for higher order abilities regardless of domain that is important in the search for the underlying disturbances in neurological development. PMID:22318760

Abu-Dahab, Sana M. N.; Holm, Margo B.; Rogers, Joan C.; Skidmore, Elizabeth; Minshew, Nancy J.

2012-01-01

405

The perceptual effects of learning object categories that predict perceptual goals.  

PubMed

In classic category learning studies, subjects typically learn to assign items to 1 of 2 categories, with no further distinction between how items on each side of the category boundary should be treated. In real life, however, we often learn categories that dictate further processing goals, for instance, with objects in only 1 category requiring further individuation. Using methods from category learning and perceptual expertise, we studied the perceptual consequences of experience with objects in tasks that rely on attention to different dimensions in different parts of the space. In 2 experiments, subjects first learned to categorize complex objects from a single morphspace into 2 categories based on 1 morph dimension, and then learned to perform a different task, either naming or a local feature judgment, for each of the 2 categories. A same-different discrimination test before and after each training measured sensitivity to feature dimensions of the space. After initial categorization, sensitivity increased along the category-diagnostic dimension. After task association, sensitivity increased more for the category that was named, especially along the nondiagnostic dimension. The results demonstrate that local attentional weights, associated with individual exemplars as a function of task requirements, can have lasting effects on perceptual representations. PMID:24820671

Van Gulick, Ana E; Gauthier, Isabel

2014-09-01

406

Perceptual effects in auralization of virtual rooms  

NASA Astrophysics Data System (ADS)

By using various types of binaural simulation (or ``auralization'') of physical environments, it is now possible to study basic perceptual issues relevant to room acoustics, as well to simulate the acoustic conditions found in concert halls and other auditoria. Binaural simulation of physical spaces in general is also important to virtual reality systems. This presentation will begin with an overview of the issues encountered in the auralization of room and other environments. We will then discuss the influence of various approximations in room modeling, in particular, edge- and surface scattering, on the perceived room response. Finally, we will discuss cross-modal effects, such as the influence of visual cues on the perception of auditory cues, and the influence of cross-modal effects on the judgement of ``perceived presence'' and the rating of room acoustic quality.

Kleiner, Mendel; Larsson, Pontus; Vastfjall, Daniel; Torres, Rendell R.

2002-05-01

407

Emerging memories  

NASA Astrophysics Data System (ADS)

Memory is a key component of any data processing system. Following the classical Turing machine approach, memories hold both the data to be processed and the rules for processing them. In the history of microelectronics, the distinction has been rather between working memory, which is exemplified by DRAM, and storage memory, exemplified by NAND. These two types of memory devices now represent 90% of all memory market and 25% of the total semiconductor market, and have been the technology drivers in the last decades. Even if radically different in characteristics, they are however based on the same storage mechanism: charge storage, and this mechanism seems to be near to reaching its physical limits. The search for new alternative memory approaches, based on more scalable mechanisms, has therefore gained new momentum. The status of incumbent memory technologies and their scaling limitations will be discussed. Emerging memory technologies will be analyzed, starting from the ones that are already present for niche applications, and which are getting new attention, thanks to recent technology breakthroughs. Maturity level, physical limitations and potential for scaling will be compared to existing memories. At the end the possible future composition of memory systems will be discussed.

Baldi, Livio; Bez, Roberto; Sandhu, Gurtej

2014-12-01

408

Light Speed!  

NSDL National Science Digital Library

Light Speed! is an OpenGL-based program developed to illustrate the effects of special relativity on the appearance of moving objects. In particular, the program allows users to see the manner in which an object is distorted based upon the viewpoint from which it is observed. In particular, Lorentz contraction, Doppler shift, the headlight effect, and optical aberration issues are highlighted at relativistic velocities.

Daniel, Richard

2009-06-10

409

Computing Speed  

NSDL National Science Digital Library

This lesson should take one day of class time. The purpose of this lesson is to develop an understanding of quadratic functions. We use the linear relation between distance, constant speed and time and the quadratic relation between the vertical distance of a falling object and time. From these, students will develop two new quadratic functions. The graph of one of these provides a picture of the physical phenomenon they have viewed.

2011-01-01

410

Perceptual Learning Improves Stereoacuity in Amblyopia  

PubMed Central

Purpose. Amblyopia is a developmental disorder that results in both monocular and binocular deficits. Although traditional treatment in clinical practice (i.e., refractive correction, or occlusion by patching and penalization of the fellow eye) is effective in restoring monocular visual acuity, there is little information on how binocular function, especially stereopsis, responds to traditional amblyopia treatment. We aim to evaluate the effects of perceptual learning on stereopsis in observers with amblyopia in the current study. Methods. Eleven observers (21.1 ± 5.1 years, six females) with anisometropic or ametropic amblyopia were trained to judge depth in 10 to 13 sessions. Red–green glasses were used to present three different texture anaglyphs with different disparities but a fixed exposure duration. Stereoacuity was assessed with the Fly Stereo Acuity Test and visual acuity was assessed with the Chinese Tumbling E Chart before and after training. Results. Averaged across observers, training significantly reduced disparity threshold from 776.7? to 490.4? (P < 0.01) and improved stereoacuity from 200.3? to 81.6? (P < 0.01). Interestingly, visual acuity also significantly improved from 0.44 to 0.35 logMAR (approximately 0.9 lines, P < 0.05) in the amblyopic eye after training. Moreover, the learning effects in two of the three retested observers were largely retained over a 5-month period. Conclusions. Perceptual learning is effective in improving stereo vision in observers with amblyopia. These results, together with previous evidence, suggest that structured monocular and binocular training might be necessary to fully recover degraded visual functions in amblyopia. Chinese Abstract PMID:24508791

Xi, Jie; Jia, Wu-Li; Feng, Li-Xia; Lu, Zhong-Lin; Huang, Chang-Bing

2014-01-01

411

Memory Impairment in Children with Language Impairment  

ERIC Educational Resources Information Center

Aim: The aim of this study was to assess whether any memory impairment co-occurring with language impairment is global, affecting both verbal and visual domains, or domain specific. Method: Visual and verbal memory, learning, and processing speed were assessed in children aged 6 years to 16 years 11 months (mean 9y 9m, SD 2y 6mo) with current,…

Baird, Gillian; Dworzynski, Katharina; Slonims, Vicky; Simonoff, Emily

2010-01-01

412

Memory System Characterization of Commercial Workloads  

Microsoft Academic Search

Commercial applications such as databases and Web servers constitute the largest and fastest-growing segment of the market for multiprocessor servers. Ongoing innovations in disk subsystems, along with the ever increasing gap between processor and memory speeds, have elevated memory system design as the critical performance factor for such workloads. However, most current server designs have been optimized to perform well

Luiz André Barroso; Kourosh Gharachorloo; Edouard Bugnion

1998-01-01

413

System-Level Integration of Mass Memory  

NASA Technical Reports Server (NTRS)

A report discusses integrating multiple memory modules on the high-speed serial interconnect (IEEE 1393) that is used by a spacecraft?s inter-module communications in order to ease data congestion and provide for a scalable, strong, flexible system that can meet new system-level mass memory requirements.

Cox, Brian; Mellstrom, Jeffrey; Wysocky, Terry

2008-01-01

414

Which Working Memory Functions Predict Intelligence?  

ERIC Educational Resources Information Center

Investigates the relationship between three factors of working memory (storage and processing, relational integration, and supervision) and four factors of intelligence (reasoning, speed, memory, and creativity) using structural equation models. Relational integration predicted reasoning ability at least as well as the storage-and-processing…

Oberauer, Klaus; Sub, Heinz-Martin; Wilhelm, Oliver; Wittmann, Werner W.

2008-01-01

415

A ratio model of perceived speed in the human visual system  

PubMed Central

The perceived speed of moving images changes over time. Prolonged viewing of a pattern (adaptation) leads to an exponential decrease in its perceived speed. Similarly, responses of neurones tuned to motion reduce exponentially over time. It is tempting to link these phenomena. However, under certain conditions, perceived speed increases after adaptation and the time course of these perceptual effects varies widely. We propose a model that comprises two temporally tuned mechanisms whose sensitivities reduce exponentially over time. Perceived speed is taken as the ratio of these filters' outputs. The model captures increases and decreases in perceived speed following adaptation and describes our data well with just four free parameters. Whilst the model captures perceptual time courses that vary widely, parameter estimates for the time constants of the underlying filters are in good agreement with estimates of the time course of adaptation of direction selective neurones in the mammalian visual system. PMID:16243695

Hammett, Stephen T; Champion, Rebecca A; Morland, Antony B; Thompson, Peter G

2005-01-01

416

On-line Learning for Covert and Overt Perceptual Capability for Vision-based Navigation  

E-print Network

On-line Learning for Covert and Overt Perceptual Capability for Vision-based Navigation Zhengping' covert and overt perceptual capabilities using reinforce- ment and supervised learning. Covert perceptual behaviors are treated as actions selected by a motivational system. Overt perceptual behaviors can

417

Copyright 1995 by Coherence LTD., all rights reserved (Revised: Oct 97 by Rafi Lohev, Oct 99 by Yair Wiseman)IBM q Computer memory is divided into levels, based on speed/cost.  

E-print Network

Copyright 1995 by Coherence LTD., all rights reserved (Revised: Oct 97 by Rafi Lohev, Oct 99 by Coherence LTD., all rights reserved (Revised: Oct 97 by Rafi Lohev, Oct 99 by Yair Wiseman)IBM 7 (Revised: Oct 97 by Rafi Lohev, Oct 99 by Yair Wiseman)IBM 7-3 The Speed/Size Hierarchy speed size cost

Wiseman, Yair

418

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

PubMed Central

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

Wilkinson, Krista M.; McIlvane, William J.

2013-01-01

419

Poor working memory predicts false memories  

Microsoft Academic Search

Two studies investigated whether individual differences in simple span verbal working memory and complex working memory capacity are related to memory accuracy and susceptibility to false memory development. In Study 1, undergraduate students (N=60) were given two simple span working memory tests: forward and backward digit span. They also underwent a memory task that is known to elicit false memories

Maarten J. V. Peters; Marko Jelicic; Hilde Verbeek; Harald Merckelbach

2007-01-01

420

Memory Skills of Deaf Learners: Implications and Applications  

ERIC Educational Resources Information Center

The author reviews research on working memory and short-term memory abilities of deaf individuals, delineating strengths and weaknesses. Among the areas of weakness that are reviewed are sequential recall, processing speed, attention, and memory load. Areas of strengths include free recall, visuospatial recall, imagery, and dual encoding.…

Hamilton, Harley

2011-01-01

421

Neural Mechanisms of Speed-Accuracy Tradeoff  

PubMed Central

SUMMARY Intelligent agents balance speed of responding with accuracy of deciding. Stochastic accumulator models commonly explain this speed-accuracy tradeoff by strategic adjustment of response threshold. Several laboratories identify specific neurons in prefrontal and parietal cortex with this accumulation process, yet no neurophysiological correlates of speed-accuracy tradeoff have been described. We trained macaque monkeys to trade speed for accuracy on cue during visual search and recorded the activity of neurons in the frontal eye field. Unpredicted by any model, we discovered that speed-accuracy tradeoff is accomplished through several distinct adjustments. Visually responsive neurons modulated baseline firing rate, sensory gain, and the duration of perceptual processing. Movement neurons triggered responses with activity modulated in a direction opposite of model predictions. Thus, current stochastic accumulator models provide an incomplete description of the neural processes accomplishing speed-accuracy tradeoffs. The diversity of neural mechanisms was reconciled with the accumulator framework through an integrated accumulator model constrained by requirements of the motor system. PMID:23141072

Heitz, Richard P.; Schall, Jeffrey D.

2012-01-01

422

Overview of emerging nonvolatile memory technologies.  

PubMed

Nonvolatile memory technologies in Si-based electronics date back to the 1990s. Ferroelectric field-effect transistor (FeFET) was one of the most promising devices replacing the conventional Flash memory facing physical scaling limitations at those times. A variant of charge storage memory referred to as Flash memory is widely used in consumer electronic products such as cell phones and music players while NAND Flash-based solid-state disks (SSDs) are increasingly displacing hard disk drives as the primary storage device in laptops, desktops, and even data centers. The integration limit of Flash memories is approaching, and many new types of memory to replace conventional Flash memories have been proposed. Emerging memory technologies promise new memories to store more data at less cost than the expensive-to-build silicon chips used by popular consumer gadgets including digital cameras, cell phones and portable music players. They are being investigated and lead to the future as potential alternatives to existing memories in future computing systems. Emerging nonvolatile memory technologies such as magnetic random-access memory (MRAM), spin-transfer torque random-access memory (STT-RAM), ferroelectric random-access memory (FeRAM), phase-change memory (PCM), and resistive random-access memory (RRAM) combine the speed of static random-access memory (SRAM), the density of dynamic random-access memory (DRAM), and the nonvolatility of Flash memory and so become very attractive as another possibility for future memory hierarchies. Many other new classes of emerging memory technologies such as transparent and plastic, three-dimensional (3-D), and quantum dot memory technologies have also gained tremendous popularity in recent years. Subsequently, not an exaggeration to say that computer memory could soon earn the ultimate commercial validation for commercial scale-up and production the cheap plastic knockoff. Therefore, this review is devoted to the rapidly developing new class of memory technologies and scaling of scientific procedures based on an investigation of recent progress in advanced Flash memory devices. PMID:25278820

Meena, Jagan Singh; Sze, Simon Min; Chand, Umesh; Tseng, Tseung-Yuen

2014-01-01

423

Overview of emerging nonvolatile memory technologies  

PubMed Central

Nonvolatile memory technologies in Si-based electronics date back to the 1990s. Ferroelectric field-effect transistor (FeFET) was one of the most promising devices replacing the conventional Flash memory facing physical scaling limitations at those times. A variant of charge storage memory referred to as Flash memory is widely used in consumer electronic products such as cell phones and music players while NAND Flash-based solid-state disks (SSDs) are increasingly displacing hard disk drives as the primary storage device in laptops, desktops, and even data centers. The integration limit of Flash memories is approaching, and many new types of memory to replace conventional Flash memories have been proposed. Emerging memory technologies promise new memories to store more data at less cost than the expensive-to-build silicon chips used by popular consumer gadgets including digital cameras, cell phones and portable music players. They are being investigated and lead to the future as potential alternatives to existing memories in future computing systems. Emerging nonvolatile memory technologies such as magnetic random-access memory (MRAM), spin-transfer torque random-access memory (STT-RAM), ferroelectric random-access memory (FeRAM), phase-change memory (PCM), and resistive random-access memory (RRAM) combine the speed of static random-access memory (SRAM), the density of dynamic random-access memory (DRAM), and the nonvolatility of Flash memory and so become very attractive as another possibility for future memory hierarchies. Many other new classes of emerging memory technologies such as transparent and plastic, three-dimensional (3-D), and quantum dot memory technologies have also gained tremendous popularity in recent years. Subsequently, not an exaggeration to say that computer memory could soon earn the ultimate commercial validation for commercial scale-up and production the cheap plastic knockoff. Therefore, this review is devoted to the rapidly developing new class of memory technologies and scaling of scientific procedures based on an investigation of recent progress in advanced Flash memory devices.

2014-01-01

424

Cognit activation: a mechanism enabling temporal integration in working memory  

PubMed Central

Working memory is critical to the integration of information across time in goal-directed behavior, reasoning and language, yet its neural substrate is unknown. Based on recent research, we propose a mechanism by which the brain can retain working memory for prospective use, thereby bridging time in the perception/action cycle. The essence of the mechanism is the activation of cognits, which consist of distributed, overlapping and interactive cortical networks that in the aggregate encode the long-term memory of the subject. Working memory depends on the excitatory reentry between perceptual and executive cognits of posterior and frontal cortices, respectively. Given the pervasive role of working memory in the structuring of purposeful cognitive sequences, its mechanism looms essential to the foundation of behavior, reasoning and language. PMID:22440831

Fuster, Joaquin M.; Bressler, Steven L.

2012-01-01

425

COGNITIVE NEUROSCIENCE A perceptual representation in the frontal eye field  

E-print Network

COGNITIVE NEUROSCIENCE A perceptual representation in the frontal eye field during covert visual selective processes, the selection of which stimulus to act upon and the selection of which action to make

Zhou, Yi-Feng

426

RACISM IN CONTEMPORARY SPORTS: A PERCEPTUAL AND CONTEXTUAL ANALYSIS.  

E-print Network

??This study examined subjects’ perceptions of racist quotations from sports figures based on three variables (objectionable-ness, racist-ness, offensiveness). This study wanted to examine perceptual and… (more)

Dickhaus, Joshua Brandon

2006-01-01

427

Perceptual tools for quality-aware video networks  

NASA Astrophysics Data System (ADS)

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."

Bovik, A. C.

2014-01-01

428

Perceptual data mining : bootstrapping visual intelligence from tracking behavior  

E-print Network

One common characteristic of all intelligent life is continuous perceptual input. A decade ago, simply recording and storing a a few minutes of full frame-rate NTSC video required special hardware. Today, an inexpensive ...

Stauffer, Christopher P. (Christopher Paul), 1971-

2002-01-01

429

An ecological perceptual aid for precision vertical landings  

E-print Network

Pilots of vertical landing vehicles face numerous control challenges which often involve the loss of outside visual perceptual cues or the control of flight parameters within tight constraints. These challenges are often ...

Smith, Cristin Anne

2006-01-01

430

The perceptual basis of long-distance laryngeal restrictions  

E-print Network

The two main arguments in this dissertation are 1. That laryngeal co-occurrence restrictions are restrictions on the perceptual strength of contrasts between roots, as opposed to restrictions on laryngeal configurations ...

Gallagher, Gillian Elizabeth Scott

2010-01-01

431

Cultural Differences in Perceptual Reorganization in US and Pirahã Adults  

PubMed Central

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

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

2014-01-01

432

A Perceptual Motor Program Model for Learning Disabled Children  

ERIC Educational Resources Information Center

The model established guidelines for a perceptual motor program for learning disabled children in the areas of student evaluation, choice of activities, goal setting, practice sessions, and reinforcement. (GW)

Eason, Robert L.; Smith, Theresa L.

1976-01-01

433

Learning Dynamics: System Identification for Perceptually Challenged Agents  

E-print Network

Learning Dynamics: System Identification for Perceptually Challenged Agents Kenneth Basye available to the agent in particular states of the environment. We view dynamical system identification efficient, high�probability learning algorithms for a number of system identification problems involving

Kaelbling, Leslie Pack

434

Perceptual Manipulations Theory Parentheses create visual groups  

E-print Network

is symbolic thought? Journal of Experimental Psychology: Learning, Memory, and Cognition. Lakoff, G. and Nuñez University, Bloomington, Indiana SYMBOLIC REASONING = NOTATION MANIPULATION Theories of general reasoning. General-Purpose Modular Account: Central processing is generally taken to consist of a repository of rules

Landy, David

435

Virtual memory  

NASA Technical Reports Server (NTRS)

Virtual memory was conceived as a way to automate overlaying of program segments. Modern computers have very large main memories, but need automatic solutions to the relocation and protection problems. Virtual memory serves this need as well and is thus useful in computers of all sizes. The history of the idea is traced, showing how it has become a widespread, little noticed feature of computers today.

Denning, P. J.

1986-01-01

436

Response Reversals in Recognition Memory  

ERIC Educational Resources Information Center

Using a dynamic sequential sampling model and a recently proposed model for confidence judgments in recognition memory (T. Van Zandt, 2000b), the authors examine the tendency for rememberers to reverse their responses after a primary decision. In 4 experiments, speeded "old"-"new" decisions were made under bias followed by a 2nd response', either…

Van Zandt, Trisha; Maldonado-Molina, Mildred M.

2004-01-01

437

Voluntary Explicit versus Involuntary Conceptual Memory Are Associated with Dissociable fMRI Responses in Hippocampus, Amygdala, and Parietal Cortex for Emotional and Neutral Word Pairs  

ERIC Educational Resources Information Center

Although functional neuroimaging studies have supported the distinction between explicit and implicit forms of memory, few have matched explicit and implicit tests closely, and most of these tested perceptual rather than conceptual implicit memory. We compared event-related fMRI responses during an intentional test, in which a group of…

Ramponi, Cristina; Barnard, Philip J.; Kherif, Ferath; Henson, Richard N.

2011-01-01

438

Working memory networks for learning multiple groupings of temporally ordered events: applications to 3-D visual object recognition  

Microsoft Academic Search

Working memory neural networks which encode the invariant temporal order of sequential events that may be presented at widely differing speeds, durations, and interstimulus intervals are characterized. Working memory, a kind of short-term memory, can be quickly erased by a distracting event, unlike long-term memory. The authors describe a working memory architecture for the storage of temporal order information across

Gary Bradski; Gail A. Carpenter; Stephen Grossberg

1991-01-01

439

Imaging tactile imagery: changes in brain connectivity support perceptual grounding of mental images in primary sensory cortices.  

PubMed

Constructing mental representations in the absence of sensory stimulation is a fundamental ability of the human mind and has been investigated in numerous brain imaging studies. However, it is still unclear how brain areas facilitating mental construction processes interact with brain regions related to specific sensory representations. In this fMRI study subjects formed mental representations of tactile stimuli either from memory (imagery) or from presentation of actual corresponding vibrotactile patterned stimuli. First our analysis addressed the question of whether tactile imagery recruits primary somatosensory cortex (SI), because the activation of early perceptual areas is classically interpreted as perceptual grounding of the mental image. We also tested whether a network, referred to as 'core construction system', is involved in the generation of mental representations in the somatosensory domain. In fact, we observed imagery-induced activation of SI. We further found support for the notion of a modality independent construction network with the retrosplenial cortices and the precuneus as core components, which were supplemented with the left inferior frontal gyrus (IFG). Finally, psychophysiological interaction (PPI) analyses revealed robust imagery-modulated changes in the connectivity of these construction related areas, which suggests that they orchestrate the assembly of an abstract mental representation. Interestingly, we found increased coupling between prefrontal cortex (left IFG) and SI during mental imagery, indicating the augmentation of an abstract mental representation by reactivating perceptually grounded sensory details. PMID:24836010

Schmidt, Timo Torsten; Ostwald, Dirk; Blankenburg, Felix

2014-09-01

440

Aphasia and sensory-perceptual deficits in children  

Microsoft Academic Search

This is the child version of Reitan's book on aphasia and sensory perceptual disorders in adults (see review by Graves, this issue). It includes a manual for two tests from the Halstead-Reitan Neuropsychological Battery (the Reitan-Indiana Aphasia Screening Test and the Reitan-Kløve Sensory-Perceptual Examination), and provides versions of the two tests for children aged 5-8 years and 9-14 years. In

Jack M. Fletcher

1987-01-01

441

Conceptual and perceptual information both influence melody identification  

Microsoft Academic Search

Three processes have been identified as central to object identification: top-down processing, bottom-up processing, and lateral\\u000a competition. Six experiments using the perceptual interference paradigm were conducted to assess the relative contributions\\u000a of these three processes to melody identification. Significant interference was observed only when the target and the distracting\\u000a information were difficult to distinguish both perceptually and conceptually. Lateral competition—the

Matthew D. Schulkind

2004-01-01

442

Direct estimation of multidimensional perceptual distributions: Assessing hue and form  

Microsoft Academic Search

The procedures developed to assess the perceptual and decisional processes associated with detection in multidimensional space\\u000a all require specialized statistical skills and analysis programs. The present article describes a regression model, designed\\u000a to assess dimensional interactions, that is both computationally simpler and more accessible than those procedures. The paper\\u000a validates the regression model by comparing the perceptual space associated with

Dale J. Cohen

2003-01-01

443

Expertise for upright faces improves the precision but not the capacity of visual working memory.  

PubMed

Considerable research has focused on how basic visual features are maintained in working memory, but little is currently known about the precision or capacity of visual working memory for complex objects. How precisely can an object be remembered, and to what extent might familiarity or perceptual expertise contribute to working memory performance? To address these questions, we developed a set of computer-generated face stimuli that varied continuously along the dimensions of age and gender, and we probed participants' memories using a method-of-adjustment reporting procedure. This paradigm allowed us to separately estimate the precision and capacity of working memory for individual faces, on the basis of the assumptions of a discrete capacity model, and to assess the impact of face inversion on memory performance. We found that observers could maintain up to four to five items on average, with equally good memory capacity for upright and upside-down faces. In contrast, memory precision was significantly impaired by face inversion at every set size tested. Our results demonstrate that the precision of visual working memory for a complex stimulus is not strictly fixed but, instead, can be modified by learning and experience. We find that perceptual expertise for upright faces leads to significant improvements in visual precision, without modifying the capacity of working memory. PMID:24627213

Lorenc, Elizabeth S; Pratte, Michael S; Angeloni, Christopher F; Tong, Frank

2014-10-01

444

Preliminary evidence that allelic variation in the LMX1A gene influences training-related working memory improvement.  

PubMed

LMX1A is a transcription factor involved in the development of dopamine (DA)-producing neurons in midbrain. Previous research has shown that allelic variations in three LMX1A single nucleotide polymorphisms (SNPs) were related to risk of Parkinson's disease (PD), suggesting that these SNPs may influence the number of mesencephalic DA neurons. Prompted by the established link between striatal DA functions and working memory (WM) performance, we examined two of these SNPs in relation to the ability to benefit from 4 weeks of WM training. One SNP (rs4657412) was strongly associated with the magnitude of training-related gains in verbal WM. The allele linked to larger gains has previously been suggested to be associated with higher dopaminergic nerve cell density. No differential gains of either SNP were observed for spatial WM, and the genotype groups were also indistinguishable in tests of attention, interference control, episodic memory, perceptual speed, and reasoning for both SNPs. This pattern of data is in agreement with previous findings from our group, suggesting that cognitive effects of DA-related genes may be more easily detected in a training context than for single-assessment performance scores. PMID:21435346

Bellander, Martin; Brehmer, Yvonne; Westerberg, Helena; Karlsson, Sari; Fürth, Daniel; Bergman, Olle; Eriksson, Elias; Bäckman, Lars

2011-06-01

445

Examining the link between information processing speed and executive functioning in multiple sclerosis.  

PubMed

Slowed information processing speed (IPS) is frequently reported in those with multiple sclerosis (MS), and at least 20% are compromised on some aspect of executive functioning also. However, any relationship between these two processes has not been examined. The Sternberg Memory Scanning Test, Processing Speed Index (WAIS-III), Delis Kaplan Executive Function System (D.KEFS), and Working Memory Index (WMS-III) were administered to 90 participants with MS. Their performance on the PSI was significantly below the normative scores but no deficits in memory scanning speed were evident. The initial response speed of the Sternberg and the PSI were more closely related to D.KEFS performance, particularly in timed tasks with a high cognitive demand (switching tasks). In contrast, memory scanning speed was related to working memory. This study reinforces the link between IPS and working memory in MS, and supports the suggestion that IPS is not a unitary construct. PMID:19395356

Drew, Margaret A; Starkey, Nicola J; Isler, Robert B

2009-02-01

446

Components of working memory and visual selective attention.  

PubMed

Load theory (Lavie, N., Hirst, A., De Fockert, J. W., & Viding, E. [2004]. Load theory of selective attention and cognitive control. Journal of Experimental Psychology: General, 133, 339-354.) proposes that control of attention depends on the amount and type of load that is imposed by current processing. Specifically, perceptual load should lead to efficient distractor rejection, whereas working memory load (dual-task coordination) should hinder distractor rejection. Studies support load theory's prediction that working memory load will lead to larger distractor effects; however, these studies used secondary tasks that required only verbal working memory and the central executive. The present study examined which other working memory components (visual, spatial, and phonological) influence visual selective attention. Subjects completed an attentional capture task alone (single-task) or while engaged in a working memory task (dual-task). Results showed that along with the central executive, visual and spatial working memory influenced selective attention, but phonological working memory did not. Specifically, attentional capture was larger when visual or spatial working memory was loaded, but phonological working memory load did not affect attentional capture. The results are consistent with load theory and suggest specific components of working memory influence visual selective attention. PMID:23875574

Burnham, Bryan R; Sabia, Matthew; Langan, Catherine

2014-02-01

447

Perceptual distance and the moon illusion.  

PubMed

The elevated moon usually appears smaller than the horizon moon of equal angular size. This is the moon illusion. Distance cues may enable the perceptual system to place the horizon moon at an effectively greater distance than the elevated moon, thus making it appear as larger. This explanation is related to the size-distance invariance hypothesis. However, the larger horizon moon is usually judged as closer than the smaller zenith moon. A bias to expect an apparently large object to be closer than a smaller object may account for this conflict. We designed experiments to determine if unbiased sensitivity to illusory differences in the size and distance of the moon (as measured by d') is consistent with SDIH. A moon above a 'terrain' was compared in both distance and size to an infinitely distant moon in empty space (the reduction moon). At a short distance the terrain moon was adjudged as both closer and smaller than the reduction moon. But these differences could not be detected at somewhat greater distances. At still greater distances the terrain moon was perceived as both more distant and larger than the reduction moon. The distances at which these transitions occurred were essentially the same for both distance and size discrimination tasks, thus supporting SDIH. PMID:17357720

Kaufman, Lloyd; Vassiliades, Vassias; Noble, Richard; Alexander, Robert; Kaufman, James; Edlund, Stefan

2007-01-01

448

The perceptual basis of common photographic practice  

PubMed Central

Photographers, cinematographers, and computer-graphics engineers use certain techniques to create striking pictorial effects. By using lenses of different focal lengths, they can make a scene look compressed or expanded in depth, make a familiar object look natural or distorted, or make a person look smarter, more attractive, or more neurotic. We asked why pictures taken with a certain focal length look natural, while those taken with other focal lengths look distorted. We found that people’s preferred viewing distance when looking at pictures leads them to view long-focal-length pictures from too near and short-focal-length pictures from too far. Perceptual distortions occur because people do not take their incorrect viewing distances into account. By following the rule of thumb of using a 50-mm lens, photographers greatly increase the odds of a viewer looking at a photograph from the correct distance, where the percept will be undistorted. Our theory leads to new guidelines for creating pictorial effects that are more effective than conventional guidelines. PMID:22637709

Cooper, Emily A.; Piazza, Elise A.; Banks, Martin S.

2012-01-01

449

Implicit perceptual anticipation triggered by statistical learning  

PubMed Central

Our environments are highly regular in terms of when and where objects appear relative to each other. Statistical learning allows us to extract and represent these regularities, but how this knowledge is used by the brain during ongoing perception is unclear. We employed rapid event-related fMRI to measure hemodynamic responses to individual visual images in a continuous stream that contained sequential contingencies. Sixteen human observers encountered these statistical regularities while performing an unrelated cognitive task, and were unaware of their existence. Nevertheless, the right anterior hippocampus showed greater hemodynamic responses to predictive stimuli, providing evidence for implicit anticipation as a consequence of unsupervised statistical learning. Hippocampal anticipation based on predictive stimuli correlated with subsequent processing of the predicted stimuli in occipital and parietal cortex, and anticipation in additional brain regions correlated with facilitated object recognition as reflected in behavioral priming. Additional analyses suggested that implicit perceptual anticipation does not contribute to explicit familiarity, but can result in predictive potentiation of category-selective ventral visual cortex. Overall, these findings show that future-oriented processing can arise incidentally during the perception of statistical regularities. PMID:20720125

Turk-Browne, Nicholas B.; Scholl, Brian J.; Johnson, Marcia K.; Chun, Marvin M.

2010-01-01

450

Perceptual basis of evolving Western musical styles  

PubMed Central

The brain processes temporal statistics to predict future events and to categorize perceptual objects. These statistics, called expectancies, are found in music perception, and they span a variety of different features and time scales. Specifically, there is evidence that music perception involves strong expectancies regarding the distribution of a melodic interval, namely, the distance between two consecutive notes within the context of another. The recent availability of a large Western music dataset, consisting of the historical record condensed as melodic interval counts, has opened new possibilities for data-driven analysis of musical perception. In this context, we present an analytical approach that, based on cognitive theories of music expectation and machine learning techniques, recovers a set of factors that accurately identifies historical trends and stylistic transitions between the Baroque, Classical, Romantic, and Post-Romantic periods. We also offer a plausible musicological and cognitive interpretation of these factors, allowing us to propose them as data-driven principles of melodic expectation. PMID:23716669

Rodriguez Zivic, Pablo H.; Shifres, Favio; Cecchi, Guillermo A.

2013-01-01

451

Investigating perceptual structure of concert hall ambiances.  

PubMed

With the advent of ultra high definition (UHD) video, a new sound reproduction system incorporating height channel to enhance audio-visual interaction is getting researchers' attention. To better understand influence of the contents for the height channel(s) on perceived sound quality, the authors have conducted a listening test wherein listeners compared various concert hall ambiances. The authors first recorded the ambiances of a hall at 175 positions (in various heights and positions) using a MIDI-controlled piano. Subsequently we investigated interrelation of ambiances with subordinate objectives: (1) reveal perceptual space of the ambiances and (2) unfold latent yet salient factors. We selected 10 ambiances placed at three-dimensional equidistant from the source as the stimuli. Fifteen musicians participated in a subjective evaluation where they reported perceived dissimilarity between two randomly presented stimuli. The dissimilarity matrices were then analyzed via INDSCAL and the results showed that the stimuli could be coordinated along two bases which corresponded to distance from the source and spectral kurtosis of the stimuli respectively. Finding those salient bases will help assist spatial audio researchers in rendering height ambiances with smaller yet relevant subset of ambiances. PMID:25236074

Kanakanahalli Nagendra, Aparna; Kim, SungYoung

2014-04-01

452

Perceptual quality metric with internal generative mechanism.  

PubMed

Objective image quality assessment (IQA) aims to evaluate image quality consistently with human perception. Most of the existing perceptual IQA metrics cannot accurately represent the degradations from different types of distortion, e.g., existing structural similarity metrics perform well on content-dependent distortions while not as well as peak signal-to-noise ratio (PSNR) on content-independent distortions. In this paper, we integrate the merits of the existing IQA metrics with the guide of the recently revealed internal generative mechanism (IGM). The IGM indicates that the human visual system actively predicts sensory information and tries to avoid residual uncertainty for image perception and understanding. Inspired by the IGM theory, we adopt an autoregressive prediction algorithm to decompose an input scene into two portions, the predicted portion with the predicted visual content and the disorderly portion with the residual content. Distortions on the predicted portion degrade the primary visual information, and structural similarity procedures are employed to measure its degradation; distortions on the disorderly portion mainly change the uncertain information and the PNSR is employed for it. Finally, according to the noise energy deployment on the two portions, we combine the two evaluation results to acquire the overall quality score. Experimental results on six publicly available databases demonstrate that the proposed metric is comparable with the state-of-the-art quality metrics. PMID:22910116

Wu, Jinjian; Lin, Weisi; Shi, Guangming; Liu, Anmin

2013-01-01

453

Perceptual organization in the tilt illusion  

PubMed Central

The tilt illusion is a paradigmatic example of contextual influences on perception. We analyze it in terms of a neural population model for the perceptual organization of visual orientation. In turn, this is based on a well-found treatment of natural scene statistics, known as the Gaussian Scale Mixture model. This model is closely related to divisive gain control in neural processing and has been extensively applied in the image processing and statistical learning communities; however, its implications for contextual effects in biological vision have not been studied. In our model, oriented neural units associated with surround tilt stimuli participate in divisively normalizing the activities of the units representing a center stimulus, thereby changing their tuning curves. We show that through standard population decoding, these changes lead to the forms of repulsion and attraction observed in the tilt illusion. The issues in our model readily generalize to other visual attributes and contextual phenomena, and should lead to more rigorous treatments of contextual effects based on natural scene statistics. PMID:19757928

Schwartz, Odelia; Sejnowski, Terrence J.; Dayan, Peter

2010-01-01

454

On security threats for robust perceptual hashing  

NASA Astrophysics Data System (ADS)

Perceptual hashing has to deal with the constraints of robustness, accuracy and security. After modeling the process of hash extraction and the properties involved in this process, two different security threats are studied, namely the disclosure of the secret feature space and the tampering of the hash. Two different approaches for performing robust hashing are presented: Random-Based Hash (RBH) where the security is achieved using a random projection matrix and Content-Based Hash (CBH) were the security relies on the difficulty to tamper the hash. As for digital watermarking, different security setups are also devised: the Batch Hash Attack, the Group Hash Attack, the Unique Hash Attack and the Sensitivity Attack. A theoretical analysis of the information leakage in the context of Random-Based Hash is proposed. Finally, practical attacks are presented: (1) Minor Component Analysis is used to estimate the secret projection of Random-Based Hashes and (2) Salient point tampering is used to tamper the hash of Content-Based Hashe