Sample records for memory perceptual speed

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

    PubMed Central

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

    2010-01-01

    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

  2. Individual Differences in Working Memory Within a Nomological Network of Cognitive and Perceptual Speed Abilities

    Microsoft Academic Search

    Phillip L. Ackerman; Margaret E. Beier; Mary O. Boyle

    2002-01-01

    It has become fashionable to equate constructs of working memory (WM) and general intelligence (g). Few investigations have provided direct evidence that WM and g measures yield similar ordering of individuals. Correlational investigations have yielded mixed results. The authors assess the construct space for WM and g and demonstrate that WM shares substantial variance with perceptual speed (PS) constructs. Thirty-six

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

    ERIC Educational Resources Information Center

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

    2009-01-01

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

  4. Dissociated Mechanisms of Extracting Perceptual Information into Visual Working Memory

    Microsoft Academic Search

    Zaifeng Gao; Jie Li; Jun Yin; Mowei Shen; Aldo Rustichini

    2010-01-01

    BackgroundThe processing mechanisms of visual working memory (VWM) have been extensively explored in the recent decade. However, how the perceptual information is extracted into VWM remains largely unclear. The current study investigated this issue by testing whether the perceptual information was extracted into VWM via an integrated-object manner so that all the irrelevant information would be extracted (object hypothesis), or

  5. Literature review and prospect on the study of perceptual speed reduction

    Microsoft Academic Search

    Bing Liu; Shunying Zhu; Hong Wang; Jing Xia

    2008-01-01

    Speed and speed variance are related to the intensity and the number of traffic accidents, and the effective control on speed and speed variance is the key to enhance the road safety. Perceptual speed reduction technology is human-oriented, which has several merits such as the low cost, initiative and so on. The article explains the research significance of perceptual speed

  6. Retrieval-Induced Forgetting in Perceptually Driven Memory Tests

    ERIC Educational Resources Information Center

    Bajo, M. Teresa; Gomez-Ariza, Carlos J.; Fernandez, Angel; Marful, Alejandra

    2006-01-01

    Recent data (T. J. Perfect, C. J. A. Moulin, M. A. Conway, & E. Perry, 2002) have suggested that retrieval-induced forgetting (RIF) depends on conceptual memory because the effect is not found in perceptually driven tasks. In 3 experiments, the authors aimed to show that the presence of RIF depends on whether the procedure induces appropriate…

  7. Retrieval-induced forgetting in perceptually driven memory tests.

    PubMed

    Bajo, M Teresa; Gómez-Ariza, Carlos J; Fernandez, Angel; Marful, Alejandra

    2006-09-01

    Recent data (T. J. Perfect, C. J. A. Moulin, M. A. Conway, & E. Perry, 2002) have suggested that retrieval-induced forgetting (RIF) depends on conceptual memory because the effect is not found in perceptually driven tasks. In 3 experiments, the authors aimed to show that the presence of RIF depends on whether the procedure induces appropriate transfer between representations and competition rather than on the nature of the final test. The authors adapted the standard paradigm to introduce lexical categories (words that shared the first 2 letters) at study and practice. Direct and indirect fragment completion tests were used at retrieval. The results showed significant RIF effects in perceptually driven tasks. Furthermore, they indicated that the presence of RIF effects depended on using adequate cuing to induce competition during the retrieval practice and on the final memory test tapping the inhibited representation. PMID:16938055

  8. When Does Modality Matter? Perceptual versus Conceptual Fluency-Based Illusions in Recognition Memory

    ERIC Educational Resources Information Center

    Miller, Jeremy K.; Lloyd, Marianne E.; Westerman, Deanne L.

    2008-01-01

    Previous research has shown that illusions of recognition memory based on enhanced perceptual fluency are sensitive to the perceptual match between the study and test phases of an experiment. The results of the current study strengthen that conclusion, as they show that participants will not interpret enhanced perceptual fluency as a sign of…

  9. The perceptual richness of complex memory episodes is compromised by medial temporal lobe damage.

    PubMed

    St-Laurent, Marie; Moscovitch, Morris; Jadd, Rachel; McAndrews, Mary Pat

    2014-05-01

    Perceptual richness, a defining feature of episodic memory, emerges from the reliving of multimodal sensory experiences. Although the importance of the medial temporal lobe (MTL) to episodic memory retrieval is well documented, the features that determine its engagement are not well characterized. The current study assessed the relationship between MTL function and episodic memory's perceptual richness. We designed a laboratory memory task meant to capture the complexity of memory for life episodes, while manipulating memory's perceptual content. Participants encoded laboratory episodes with rich (film clips) and impoverished (written narratives) perceptual content that were matched for other characteristics such as personal significance, emotionality and story content. At retrieval, participants were probed to describe the stories' perceptual features and storyline. Participants also recalled autobiographical memories (AMs) in a comparison condition. We compared the performance of patients with unilateral medial temporal lobe epilepsy (mTLE) and healthy controls to assess how damage to the MTL affects retrieval in these conditions. We observed an overall decrease in detail count in the mTLE group, along with a disproportionate deficit in perceptual details that was most acute in the AM and the perceptually enriched film clip conditions. Our results suggest that the impaired sense of reliving the past that accompanies MTL insult is mediated by a paucity of perceptual episodic memory details. We also introduce a new protocol that successfully mimics naturalistic memories while benefiting from the experimental control provided by using laboratory stimuli. PMID:24449286

  10. Fluency Effects in Recognition Memory: Are Perceptual Fluency and Conceptual Fluency Interchangeable?

    ERIC Educational Resources Information Center

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

    2014-01-01

    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…

  11. Prior perceptual processing enhances the effect of emotional arousal on the neural correlates of memory retrieval

    PubMed Central

    Dew, Ilana T. Z.; Ritchey, Maureen; LaBar, Kevin S.; Cabeza, Roberto

    2014-01-01

    A fundamental idea in memory research is that items are more likely to be remembered if encoded with a semantic, rather than perceptual, processing strategy. Interestingly, this effect has been shown to reverse for emotionally arousing materials, such that perceptual processing enhances memory for emotional information or events. The current fMRI study investigated the neural mechanisms of this effect by testing how neural activations during emotional memory retrieval are influenced by the prior encoding strategy. Participants incidentally encoded emotional and neutral pictures under instructions to attend to either semantic or perceptual properties of each picture. Recognition memory was tested two days later. fMRI analyses yielded three main findings. First, right amygdalar activity associated with emotional memory strength was enhanced by prior perceptual processing. Second, prior perceptual processing of emotional pictures produced a stronger effect on recollection- than familiarity-related activations in the right amygdala and left hippocampus. Finally, prior perceptual processing enhanced amygdalar connectivity with regions strongly associated with retrieval success, including hippocampal/parahippocampal regions, visual cortex, and ventral parietal cortex. Taken together, the results specify how encoding orientations yield alterations in brain systems that retrieve emotional memories. PMID:24380867

  12. Kirshner Saroj Visual Perceptual Speed Test: A Test of Visual Readiness for Reading.

    ERIC Educational Resources Information Center

    Kirshner, A. J.; Saroj, Satish K.

    Described is the Kirshner Saroj Visual Perception Speed Test (KSVPST), a measure of perceptual speed using pictures to identify children whose reading difficulties are due to visual processing deficiencies. It is explained that 323 children 6-13 years old were given the Keystone Visual Skills Test, the KSVPST, and reading readiness tests. Data are…

  13. The Competitive Influences of Perceptual Load and Working Memory Guidance on Selective Attention

    PubMed Central

    Tan, Jinfeng; Zhao, Yuanfang; Wang, Lijun; Tian, Xia; Cui, Yan; Yang, Qian; Pan, Weigang; Zhao, Xiaoyue; Chen, Antao

    2015-01-01

    The perceptual load theory in selective attention literature proposes that the interference from task-irrelevant distractor is eliminated when perceptual capacity is fully consumed by task-relevant information. However, the biased competition model suggests that the contents of working memory (WM) can guide attentional selection automatically, even when this guidance is detrimental to visual search. An intriguing but unsolved question is what will happen when selective attention is influenced by both perceptual load and WM guidance. To study this issue, behavioral performances and event-related potentials (ERPs) were recorded when participants were presented with a cue to either identify or hold in memory and had to perform a visual search task subsequently, under conditions of low or high perceptual load. Behavioural data showed that high perceptual load eliminated the attentional capture by WM. The ERP results revealed an obvious WM guidance effect in P1 component with invalid trials eliciting larger P1 than neutral trials, regardless of the level of perceptual load. The interaction between perceptual load and WM guidance was significant for the posterior N1 component. The memory guidance effect on N1 was eliminated by high perceptual load. Standardized Low Resolution Electrical Tomography Analysis (sLORETA) showed that the WM guidance effect and the perceptual load effect on attention can be localized into the occipital area and parietal lobe, respectively. Merely identifying the cue produced no effect on the P1 or N1 component. These results suggest that in selective attention, the information held in WM could capture attention at the early stage of visual processing in the occipital cortex. Interestingly, this initial capture of attention by WM could be modulated by the level of perceptual load and the parietal lobe mediates target selection at the discrimination stage. PMID:26098079

  14. Disruption of Dorsolateral But Not Ventrolateral Prefrontal Cortex Improves Unconscious Perceptual Memories

    PubMed Central

    Blumenfeld, Robert S.; D'Esposito, Mark

    2013-01-01

    Attentive encoding often leads to more accurate responses in recognition memory tests. However, previous studies have described conditions under which taxing explicit memory resources by attentional distraction improved perceptual recognition memory without awareness. These findings lead to the hypothesis that explicit memory processes mediated by the prefrontal cortex (PFC) can interfere with memory processes necessary for implicit recognition memory. The present study directly tested this hypothesis by applying transcranial magnetic stimulation separately over either dorsolateral (DLPFC) or ventrolateral PFC (VLPFC) in humans before performance of a visual memory task. Disruption of DLPFC function led to improvement in recognition accuracy only in responses in which the participant's awareness of memory retrieval was absent. However, disruption of VLPFC function led to subtle shifts in recollection and familiarity accuracy. We conclude that explicit memory processes mediated by the DLPFC can indirectly interfere with implicit recognition memory. PMID:23926275

  15. High speed submicron BiCMOS memory

    Microsoft Academic Search

    Masahide Takada; Kazuyuki Nakamura; Tohru Yamazaki

    1995-01-01

    This paper reviews device and circuit technologies for submicron BiCMOS memories, especially for high speed and large capacity SRAM's with 0.8 ?m, 0.55 ?m and 0.4 ?m design rules. First, poly-silicon emitter structure and triple-well structure are described as key submicron BiCMOS device technologies for achieving high transistor performance and minimized process complexity, as well as high reliability. Next, submicron

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

    ERIC Educational Resources Information Center

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

    2013-01-01

    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…

  17. 1654 Learning and memory Perceptual and motor factors of implicit skill learning

    E-print Network

    Nemeth, Dezso

    to the environment and to evaluate events. The most important models of skill learning in cognitive neuroscience in the egocentric space (answer-based learning) or by the finger movement patterns (effector-based learning) [81654 Learning and memory Perceptual and motor factors of implicit skill learning Dezso Nemetha

  18. Perceptual and attentional effects on drivers’ speed selection at curves

    Microsoft Academic Search

    Samuel G Charlton

    2004-01-01

    This paper describes an experiment comparing the relative effectiveness of various types of warnings on drivers’ speed selection at curves. The experiment compared three types of curve warnings across three different curve types in a driving simulator. All of the warnings worked reasonably well for severe curves (45km\\/h), regardless of demands from a secondary (cell phone) task. For less demanding

  19. Perceptual difficulty in source memory encoding and retrieval: prefrontal versus parietal electrical brain activity.

    PubMed

    Kuo, Trudy Y; Van Petten, Cyma

    2008-01-01

    It is well established that source memory retrieval--remembering relationships between a core item and some additional attribute of an event--engages prefrontal cortex (PFC) more than simple item memory. In event-related potentials (ERPs), this is manifest in a late-onset difference over PFC between studied items which mandate retrieval of a second attribute, and unstudied items which can be immediately rejected. Although some sorts of attribute conjunctions are easier to remember than others, the role of source retrieval difficulty on prefrontal activity has received little attention. We examined memory for conjunctions of object shape and color when color was an integral part of the depicted object, and when monochrome objects were surrounded by colored frames. Source accuracy was reliably worse when shape and color were spatially separated, but prefrontal activity did not vary across the object-color and frame-color conditions. The insensitivity of prefrontal ERPs to this perceptual manipulation of difficulty stands in contrast to their sensitivity to encoding task: deliberate voluntary effort to integrate objects and colors during encoding reduced prefrontal activity during retrieval, but perceptual organization of stimuli did not. The amplitudes of ERPs over parietal cortex were larger for frame-color than object-color stimuli during both study and test phases of the memory task. Individual variability in parietal ERPs was strongly correlated with memory accuracy, which we suggest reflects a contribution of visual working memory to long-term memory. We discuss multiple bottlenecks for source memory performance. PMID:18402989

  20. Perceptual difficulty in source memory encoding and retrieval: Prefrontal versus parietal electrical brain activity

    PubMed Central

    Kuo, Trudy Y.; Van Petten, Cyma

    2008-01-01

    It is well established that source memory retrieval – remembering relationships between a core item and some additional attribute of an event – engages prefrontal cortex (PFC) more than simple item memory. In event-related potentials (ERPs), this is manifest in a late-onset difference over PFC between studied items which mandate retrieval of a second attribute, and unstudied items which can be immediately rejected. Although some sorts of attribute conjunctions are easier to remember than others, the role of source retrieval difficulty on prefrontal activity has received little attention. We examined memory for conjunctions of object shape and color when color was an integral part of the depicted object, and when monochrome objects were surrounded by colored frames. Source accuracy was reliably worse when shape and color were spatially separated, but prefrontal activity did not vary across the object–color and frame-color conditions. The insensitivity of prefrontal ERPs to this perceptual manipulation of difficulty stands in contrast to their sensitivity to encoding task: deliberate voluntary effort to integrate objects and colors during encoding reduced prefrontal activity during retrieval, but perceptual organization of stimuli did not. The amplitudes of ERPs over parietal cortex were larger for frame-color than object–color stimuli during both study and test phases of the memory task. Individual variability in parietal ERPs was strongly correlated with memory accuracy, which we suggest reflects a contribution of visual working memory to long-term memory. We discuss multiple bottlenecks for source memory performance. PMID:18402989

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

    PubMed

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

    2014-10-01

    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. PMID:24933517

  2. FPGA Flash Memory High Speed Data Acquisition

    NASA Technical Reports Server (NTRS)

    Gonzalez, April

    2013-01-01

    The purpose of this research is to design and implement a VHDL ONFI Controller module for a Modular Instrumentation System. The goal of the Modular Instrumentation System will be to have a low power device that will store data and send the data at a low speed to a processor. The benefit of such a system will give an advantage over other purchased binary IP due to the capability of allowing NASA to re-use and modify the memory controller module. To accomplish the performance criteria of a low power system, an in house auxiliary board (Flash/ADC board), FPGA development kit, debug board, and modular instrumentation board will be jointly used for the data acquisition. The Flash/ADC board contains four, 1 MSPS, input channel signals and an Open NAND Flash memory module with an analog to digital converter. The ADC, data bits, and control line signals from the board are sent to an Microsemi/Actel FPGA development kit for VHDL programming of the flash memory WRITE, READ, READ STATUS, ERASE, and RESET operation waveforms using Libero software. The debug board will be used for verification of the analog input signal and be able to communicate via serial interface with the module instrumentation. The scope of the new controller module was to find and develop an ONFI controller with the debug board layout designed and completed for manufacture. Successful flash memory operation waveform test routines were completed, simulated, and tested to work on the FPGA board. Through connection of the Flash/ADC board with the FPGA, it was found that the device specifications were not being meet with Vdd reaching half of its voltage. Further testing showed that it was the manufactured Flash/ADC board that contained a misalignment with the ONFI memory module traces. The errors proved to be too great to fix in the time limit set for the project.

  3. The Effect of Perceptual Distinctiveness on the Prospective and Retrospective Components of Prospective Memory in Young and Old Adults

    Microsoft Academic Search

    Anna-Lisa Cohen; Roger A. Dixon; D. Stephen Lindsay; Michael E. J. Masson

    2003-01-01

    In two experiments, the effect of perceptual distinctiveness of cues on prospective memory performance was examined. Young and older adults completed a visual search task with embedded prospective memory instructions. On each trial, participants were asked to indicate the position of a target letter in a letter string, unless either of two letters previously identified as prospective memory cues was

  4. The Comparison of Visual Working Memory Representations with Perceptual Inputs

    ERIC Educational Resources Information Center

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

    2009-01-01

    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. In this study, the authors tested the hypothesis that differences between the memory of a stimulus array and the perception of a…

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

    Microsoft Academic Search

    Colin M MacLeod; Michael E. J. Masson

    2000-01-01

    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

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

    PubMed

    Cerles, Mélanie; Rousset, Stéphane

    2012-08-01

    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

  7. Speeding up the Memory Hierarchy in Flat COMA Multiprocessors 1

    E-print Network

    Torrellas, Josep

    Speeding up the Memory Hierarchy in Flat COMA Multiprocessors 1 Liuxi Yang and Josep Torrellas Architectures (Flat COMA) are designed for reduced memory access latencies while minimizing programmer and operating system support is called Flat Cache­Only Memory Architecture (Flat COMA) [16]. Flat COMA machines

  8. Age-related effects on perceptual and semantic encoding in memory.

    PubMed

    Kuo, M C C; Liu, K P Y; Ting, K H; Chan, C C H

    2014-03-01

    This study examined the age-related subsequent memory effect (SME) in perceptual and semantic encoding using event-related potentials (ERPs). Seventeen younger adults and 17 older adults studied a series of Chinese characters either perceptually (by inspecting orthographic components) or semantically (by determining whether the depicted object makes sounds). The two tasks had similar levels of difficulty. The participants made studied or unstudied judgments during the recognition phase. Younger adults performed better in both conditions, with significant SMEs detected in the time windows of P2, N3, P550, and late positive component (LPC). In the older group, SMEs were observed in the P2 and N3 latencies in both conditions but were only detected in the P550 in the semantic condition. Between-group analyses showed larger frontal and central SMEs in the younger sample in the LPC latency regardless of encoding type. Aging effect appears to be stronger on influencing perceptual than semantic encoding processes. The effects seem to be associated with a decline in updating and maintaining representations during perceptual encoding. The age-related decline in the encoding function may be due in part to changes in frontal lobe function. PMID:24374080

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

    ERIC Educational Resources Information Center

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

    2007-01-01

    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…

  10. The Perceptual Root of Object-Based Storage: An Interactive Model of Perception and Visual Working Memory

    ERIC Educational Resources Information Center

    Gao, Tao; Gao, Zaifeng; Li, Jie; Sun, Zhongqiang; Shen, Mowei

    2011-01-01

    Mainstream theories of visual perception assume that visual working memory (VWM) is critical for integrating online perceptual information and constructing coherent visual experiences in changing environments. Given the dynamic interaction between online perception and VWM, we propose that how visual information is processed during visual…

  11. Long-Term Perceptual Memory in Educable and Trainable Retardates and Children with Learning Disabilities. Final Report.

    ERIC Educational Resources Information Center

    Raskin, Larry M.

    Three short studies were conducted on long-term effects of visual perception training on perceptual memory, involving the visual illusion of apparent movement, in educable and trainable mentally retarded children (EMR and TMR) and in learning disabled children (LD). Variables were lengths of training session and retention interval. Tables…

  12. High speed spatially multimode atomic memory

    E-print Network

    Golubeva, T; Mishina, O; Giacobino, E

    2010-01-01

    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.

  13. High speed spatially multimode atomic memory

    E-print Network

    T. Golubeva; Yu. Golubev; O. Mishina; A. Bramati; J. Laurat; E. Giacobino

    2011-02-25

    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.

  14. High-speed spatially multimode atomic memory

    SciTech Connect

    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

    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.

  15. Breaking the Speed Limits of Phase-Change Memory

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

    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.

  16. Performance gains in memory have traditionally been obtained by increasing memory bus widths and speeds. The

    E-print Network

    Jacob, Bruce

    widths and speeds. The diminishing returns of such techniques have led to the proposal of an alternate architecture, the Fully-Buffered DIMM. This new standard replaces the conventional memory bus with a narrow DDRx based memory controller policies for scheduling and row buffer management perform on a Fully

  17. High speed magneto-resistive random access memory

    NASA Technical Reports Server (NTRS)

    Wu, Jiin-Chuan (inventor); Stadler, Henry L. (inventor); Katti, Romney R. (inventor)

    1992-01-01

    A high speed read MRAM memory element is configured from a sandwich of magnetizable, ferromagnetic film surrounding a magneto-resistive film which may be ferromagnetic or not. One outer ferromagnetic film has a higher coercive force than the other and therefore remains magnetized in one sense while the other may be switched in sense by a switching magnetic field. The magneto-resistive film is therefore sensitive to the amplitude of the resultant field between the outer ferromagnetic films and may be constructed of a high resistivity, high magneto-resistive material capable of higher sensing currents. This permits higher read voltages and therefore faster read operations. Alternate embodiments with perpendicular anisotropy, and in-plane anisotropy are shown, including an embodiment which uses high permeability guides to direct the closing flux path through the magneto-resistive material. High density, high speed, radiation hard, memory matrices may be constructed from these memory elements.

  18. Language and Short-Term Memory: The Role of Perceptual-Motor Affordance

    PubMed Central

    2014-01-01

    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

  19. Galvanic vestibular stimulation speeds visual memory recall.

    PubMed

    Wilkinson, David; Nicholls, Sophie; Pattenden, Charlotte; Kilduff, Patrick; Milberg, William

    2008-08-01

    The experiments of Alessandro Volta were amongst the first to indicate that visuo-spatial function can be altered by stimulating the vestibular nerves with galvanic current. Until recently, the beneficial effects of the procedure were masked by the high levels of electrical current applied, which induced nystagmus-related gaze deviation and spatial disorientation. However, several neuropsychological studies have shown that much weaker, imperceptible currents that do not elicit unpleasant side-effects can help overcome visual loss after stroke. Here, we show that visual processing in neurologically healthy individuals can also benefit from galvanic vestibular stimulation. Participants first learnt the names of eight unfamiliar faces and then after a short delay, answered questions from memory about how pairs of these faces differed. Mean correct reaction times were significantly shorter when sub-sensory, noise-enhanced anodal stimulation was administered to the left mastoid, compared to when no stimulation was administered at all. This advantage occurred with no loss in response accuracy, and raises the possibility that the procedure may constitute a more general form of cognitive enhancement. PMID:18584162

  20. Integrated, nonvolatile, high-speed analog random access memory

    NASA Technical Reports Server (NTRS)

    Katti, Romney R. (inventor); Wu, Jiin-Chuan (inventor); Stadler, Henry L. (inventor)

    1994-01-01

    This invention provides an integrated, non-volatile, high-speed random access memory. A magnetically switchable ferromagnetic or ferrimagnetic layer is sandwiched between an electrical conductor which provides the ability to magnetize the magnetically switchable layer and a magneto resistive or Hall effect material which allows sensing the magnetic field which emanates from the magnetization of the magnetically switchable layer. By using this integrated three-layer form, the writing process, which is controlled by the conductor, is separated from the storage medium in the magnetic layer and from the readback process which is controlled by the magnetoresistive layer. A circuit for implementing the memory in CMOS or the like is disclosed.

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

    PubMed Central

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

    2014-01-01

    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. PMID:25431557

  2. High-speed optical interconnects for video memory

    NASA Astrophysics Data System (ADS)

    Amin Hanjani, Amir H.

    2001-07-01

    The purpose of this work has been to design, model and experimentally verify a large fast-access memory array based on the use of GaAs charge-coupled devices and an optical fiber interconnection network for synchronous clocking of the CCDs. The large memory array was to consist of 16 levels of (planar) modules with 16 large GaAs CCD memory chips (2cm x 2cm) per plane. This memory needed to be synchronously clocked so that it could deliver two dimensional pattern arrays of 4096 x 4096 pixels in 256 colors for testing high-resolution monitors. Since the CCDs to be used had already been fabricated and tested in previous work, the present work has focused on the design and implementation of the optical interconnect scheme because experimental information is lacking here which is essential for a complete verification of the large memory array design. This effort therefore included the design of an optical receiver to be fabricated in a buffered FET Logic (BFL) process because this matches the fabrication process used for the CCDs. Thus the results of this work and the previous CCD work would serve to finalize the verification of a complete MCM (multi-chip- module) memory before construction begins. Since MCM system are costly and time-consuming to produce it is essential to demonstrate a near-to-life simulation of the system beforehand. An integrated MSM photodetector with MESFET transimpedance amplifier with gain control capability was designed to match the GaAs CCDs fabrication process and provides necessary speed of response and gain for the photonic interconnects purpose. The issues involved in the process of optical fiber coupling to laser and photodetector were studied and modeled. Finally, the photonic interconnect link were fabricated and characterized in terms of clock skew, loss and reliability.

  3. Opposite effects of perceptual and working memory load on perceptual filling-in of an artificial scotoma

    Microsoft Academic Search

    Rimona S. Weil; Victoria Wykes; David Carmel; Geraint Rees

    2011-01-01

    A target presented on a background of dynamic noise disappears from awareness after a few seconds of maintained peripheral viewing. Whereas the effects of bottom-up factors in such filling-in are well documented, the roles of different top-down functions remain relatively unexplored. Here, we investigated the roles of attention and working memory (WM) by manipulating load in concurrent tasks while participants

  4. Opposite effects of perceptual and working memory load on perceptual filling-in of an artificial scotoma

    Microsoft Academic Search

    Rimona S. Weil; Victoria Wykes; David Carmel; Geraint Rees

    2012-01-01

    A target presented on a background of dynamic noise disappears from awareness after a few seconds of maintained peripheral viewing. Whereas the effects of bottom-up factors in such filling-in are well documented, the roles of different top-down functions remain relatively unexplored. Here, we investigated the roles of attention and working memory (WM) by manipulating load in concurrent tasks while participants

  5. Delayed discrimination of spatial frequency for gratings of diVerent orientation: behavioral and fMRI evidence for low-level perceptual memory stores in early visual cortex

    Microsoft Academic Search

    Oliver Baumann; Tor Endestad; Svein Magnussen; Mark W. Greenlee

    2008-01-01

    The concept of perceptual memory refers to the neural and cognitive processes underlying the storage of speciWc stimulus features such as spatial frequency, orienta- tion, shape, contrast, and color. Psychophysical studies of perceptual memory indicate that observers can retain visual information about the spatial frequency of Gabor patterns independent of the orientation with which they are pre- sented. Compared to

  6. Speed Matters: Relationship between Speed of Eye Movements and Modification of Aversive Autobiographical Memories

    PubMed Central

    van Veen, Suzanne Chantal; van Schie, Kevin; Wijngaards-de Meij, Leoniek D. N. V.; Littel, Marianne; Engelhard, Iris M.; van den Hout, Marcel A.

    2015-01-01

    Eye movement desensitization and reprocessing (EMDR) is an efficacious treatment for post-traumatic stress disorder. In EMDR, patients recall a distressing memory and simultaneously make eye movements (EM). Both tasks are considered to require limited working memory (WM) resources. Because this leaves fewer resources available for memory retrieval, the memory should become less vivid and less emotional during future recall. In EMDR analogue studies, a standardized procedure has been used, in which participants receive the same dual task manipulation of 1 EM cycle per second (1?Hz). From a WM perspective, the WM taxation of the dual task might be titrated to the WM taxation of the memory image. We hypothesized that highly vivid images are more affected by high WM taxation and less vivid images are more affected by low WM taxation. In study 1, 34 participants performed a reaction time task, and rated image vividness, and difficulty of retrieving an image, during five speeds of EM and no EM. Both a high WM taxing frequency (fast EM; 1.2?Hz) and a low WM taxing frequency (slow EM; 0.8?Hz) were selected. In study 2, 72 participants recalled three highly vivid aversive autobiographical memory images (n =?36) or three less vivid images (n =?36) under each of three conditions: recall?+?fast EM, recall?+?slow EM, or recall only. Multi-level modeling revealed a consistent pattern for all outcome measures: recall?+?fast EM led to less emotional, less vivid and more difficult to retrieve images than recall?+?slow EM and recall only, and the effects of recall?+?slow EM felt consistently in between the effects of recall?+?fast EM and recall only, but only differed significantly from recall?+?fast EM. Crucially, image vividness did not interact with condition on the decrease of emotionality over time, which was inconsistent with the prediction. Implications for understanding the mechanisms of action in memory modification and directions for future research are discussed. PMID:25904871

  7. Speed Matters: Relationship between Speed of Eye Movements and Modification of Aversive Autobiographical Memories.

    PubMed

    van Veen, Suzanne Chantal; van Schie, Kevin; Wijngaards-de Meij, Leoniek D N V; Littel, Marianne; Engelhard, Iris M; van den Hout, Marcel A

    2015-01-01

    Eye movement desensitization and reprocessing (EMDR) is an efficacious treatment for post-traumatic stress disorder. In EMDR, patients recall a distressing memory and simultaneously make eye movements (EM). Both tasks are considered to require limited working memory (WM) resources. Because this leaves fewer resources available for memory retrieval, the memory should become less vivid and less emotional during future recall. In EMDR analogue studies, a standardized procedure has been used, in which participants receive the same dual task manipulation of 1 EM cycle per second (1?Hz). From a WM perspective, the WM taxation of the dual task might be titrated to the WM taxation of the memory image. We hypothesized that highly vivid images are more affected by high WM taxation and less vivid images are more affected by low WM taxation. In study 1, 34 participants performed a reaction time task, and rated image vividness, and difficulty of retrieving an image, during five speeds of EM and no EM. Both a high WM taxing frequency (fast EM; 1.2?Hz) and a low WM taxing frequency (slow EM; 0.8?Hz) were selected. In study 2, 72 participants recalled three highly vivid aversive autobiographical memory images (n =?36) or three less vivid images (n =?36) under each of three conditions: recall?+?fast EM, recall?+?slow EM, or recall only. Multi-level modeling revealed a consistent pattern for all outcome measures: recall?+?fast EM led to less emotional, less vivid and more difficult to retrieve images than recall?+?slow EM and recall only, and the effects of recall?+?slow EM felt consistently in between the effects of recall?+?fast EM and recall only, but only differed significantly from recall?+?fast EM. Crucially, image vividness did not interact with condition on the decrease of emotionality over time, which was inconsistent with the prediction. Implications for understanding the mechanisms of action in memory modification and directions for future research are discussed. PMID:25904871

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

    PubMed Central

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

    2014-01-01

    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

  9. Comparing the benefits of caffeine, naps and placebo on verbal, motor and perceptual memory

    Microsoft Academic Search

    Sara C. Mednick; Denise J. Cai; Jennifer Kanady; Sean P. A. Drummond

    2008-01-01

    Caffeine, the world's most common psychoactive substance, is used by approximately 90% of North Americans everyday. Little is known, however, about its benefits for memory. Napping has been shown to increase alertness and promote learning on some memory tasks. We directly compared caffeine (200mg) with napping (60–90min) and placebo on three distinct memory processes: declarative verbal memory, procedural motor skills,

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

    Microsoft Academic Search

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

    2006-01-01

    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

  11. Novel SOI-Specific circuit form high-speed radiation-hardened memories

    Microsoft Academic Search

    T. P. Haraszti; R. Pancholy; J. Chona; R. Schober; K. Hunt

    2008-01-01

    In all of th seven main memory components, the use of the novel SOI-specific sense amplifiers, memory-cells, and logic gates, envinced exceptionally speedy operations. This made possible fabrication and tests of complete memories which feature 2.2 GHz operational speed, 10-12 error\\/bit\\/day and 1 Mrad total dose hardness. The SOI memories can indeed provide substantially faster operations than their best bulk

  12. Letter-recognition and reading speed in peripheral vision benefit from perceptual learning

    Microsoft Academic Search

    Susana T. L. Chung; Gordon E. Legge; Sing-hang Cheung

    2004-01-01

    Visual-span profiles are plots of letter-recognition accuracy as a function of letter position left or right of the midline. Previously, we have shown that contraction of these profiles in peripheral vision can account for slow reading speed in peripheral vision. In this study, we asked two questions: (1) can we modify visual-span profiles through training on letter-recognition, and if so,

  13. Neural dynamics of speech and language coding: developmental programs, perceptual grouping, and competition for short-term memory.

    PubMed

    Cohen, M; Grossberg, S

    1986-01-01

    A computational theory of how an observer parses a speech stream into context-sensitive language representations is described. It is shown how temporal lists of events can be chunked into unitized representations, how perceptual groupings of past item sublists can be reorganized due to information carried by newly occurring items, and how item information and temporal order information are bound together into context-sensitive codes. These language units are emergent properties due to intercellular interactions among large numbers of nerve cells. The controlling neural networks can arise through simple rules of neuronal development: random growth of connections along spatial gradients, activity-dependent self-similar cell growth, and competition for conserved synaptic sites. Within these networks, a spatial frequency analysis of temporally evolving activity patterns leads to competitive masking of inappropriate list encodings in short term memory. The neurons obey membrane equations undergoing shunting recurrent on-center off-surround interactions. Several design principles are embodied by the networks, such as the sequence masking principle, the long-term memory invariance principle, and the principle of self-similar growth. PMID:3516940

  14. Fast Learning of Simple Perceptual Discriminations Reduces Brain Activation in Working Memory and in High-level Auditory Regions.

    PubMed

    Daikhin, Luba; Ahissar, Merav

    2015-07-01

    Introducing simple stimulus regularities facilitates learning of both simple and complex tasks. This facilitation may reflect an implicit change in the strategies used to solve the task when successful predictions regarding incoming stimuli can be formed. We studied the modifications in brain activity associated with fast perceptual learning based on regularity detection. We administered a two-tone frequency discrimination task and measured brain activation (fMRI) under two conditions: with and without a repeated reference tone. Although participants could not explicitly tell the difference between these two conditions, the introduced regularity affected both performance and the pattern of brain activation. The "No-Reference" condition induced a larger activation in frontoparietal areas known to be part of the working memory network. However, only the condition with a reference showed fast learning, which was accompanied by a reduction of activity in two regions: the left intraparietal area, involved in stimulus retention, and the posterior superior-temporal area, involved in representing auditory regularities. We propose that this joint reduction reflects a reduction in the need for online storage of the compared tones. We further suggest that this change reflects an implicit strategic shift "backwards" from reliance mainly on working memory networks in the "No-Reference" condition to increased reliance on detected regularities stored in high-level auditory networks. PMID:25603023

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

    PubMed

    Zeithamova, Dagmar; Maddox, W Todd

    2007-09-01

    The role of verbal and visuospatial working memory in rule-based and information-integration category learning was examined. Previously, Maddox, Ashby, Ing, and Pickering found that a sequentially presented verbal working memory task did not affect information-integration learning, but disrupted rule-based learning when the rule was on the spatial frequency of a Gabor stimulus. This pattern was replicated in Experiment 1, in which the same category structures were used, but in which the verbal working memory task was replaced with a visuospatial analog. Experiment 2A examined rule-based learning on an oblique orientation and also found both verbal and visuospatial working memory tasks disrupting learning. Experiment 2B examined rule-based learning on a cardinal orientation and found a minimal effect of the verbal working memory task, but a large effect of the visuospatial working memory task. The conceptual significance of cardinal orientations and the role of visuospatial and verbal working memory in category learning are discussed. PMID:18035635

  16. Letter Processing and the Formation of Memory Representations in Children with Naming Speed Deficits

    ERIC Educational Resources Information Center

    Conrad, Nicole J.; Levy, Betty Ann

    2007-01-01

    The ability to recognize letter patterns within words as a single unit is important for fluent reading. This skill is based on previously established memory representations of common letter patterns. The ability to form these memory representations may be impaired in some poor readers, particularly readers with naming speed deficits (NSD). This…

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

    PubMed Central

    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.

    2012-01-01

    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. PMID:22496956

  18. Transfer-Appropriate Processing in Recognition Memory: Perceptual and Conceptual Effects on Recognition Memory Depend on Task Demands

    ERIC Educational Resources Information Center

    Parks, Colleen M.

    2013-01-01

    Research examining the importance of surface-level information to familiarity in recognition memory tasks is mixed: Sometimes it affects recognition and sometimes it does not. One potential explanation of the inconsistent findings comes from the ideas of dual process theory of recognition and the transfer-appropriate processing framework, which…

  19. Low-cost high-speed associative memory

    Microsoft Academic Search

    R. M. Lea

    1975-01-01

    A design for a 256 bit dynamic MOS associative memory, integrated on a 60×80 mil chip, is described. Computer simulation studies predict match, read, and write access times of less than 10 ns. Line capacities are sufficiently small to allow quite large associative memory arrays to be controlled by cheap peripheral circuitry.

  20. High speed optical object recognition processor with massive holographic memory

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    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.

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

    E-print Network

    Vitorino Ramos

    2005-11-22

    of emergent adaptive memory, cooperative learning and perception [50 ... one of two fundamental different types of ant's sense-data. 1. Grassé, P.P.: ..... migration behavior between one deep valley (south region) and one peak. (north region) .... clouds of agents congregate in one big cluster, and the chase continues with ...

  2. Scalable, memory efficient, high-speed IP lookup algorithms

    Microsoft Academic Search

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

    2005-01-01

    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

  3. New High Speed GaAs Memory Cell

    Microsoft Academic Search

    A. Bernal; R. P. Ribas; A. Guyot

    This paper describes an experimental GaAs MESFET static memory cell which overcomes the principal disadvantages of the conventional cell implementation. Cell size is 36x37 ?m2 at 0.6 ?m gate length. An experimental 32 word x 32bit array has been designed. From simulation results, an address access time of 1ns has been obtained. The cell can be operated at the single

  4. On the immunity of perceptual implicit memory to manipulations of attention.

    PubMed

    Newell, Ben R; Cavenett, Tamara; Andrews, Sally

    2008-06-01

    In four experiments, we examined the effect of manipulating study phase attention in a Stroop task on the extent of repetition priming in the lexical decision task (LDT). Experiment 1 replicated the immunity of the LDT to division of attention reported by Szymanski and MacLeod (1996), using a standard Stroop configuration. Response times to previously encountered words were identical regardless of whether the participants were required to read the words or name the color in which they were presented. Experiment 2 demonstrated that implementing the Stroop manipulation across separate visual objects reduced but did not eliminate priming of unattended words, provided the words remained in the attended region of the stimulus display. When this constraint was removed in Experiment 3, priming of unattended words disappeared. Experiment 4 demonstrated statistically equivalent priming for attended and unattended words when the Stroop manipulation remained in the same visual object but attention was directed to a single letter of the word. In all four experiments, the Stroop manipulation had a clear effect on recognition. These results qualify claims that the LDT might be immune to manipulations of study phase attention and suggest that the LDT has a lower threshold level of attention at encoding than do other standard implicit tests of memory. PMID:18604956

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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.…

  6. Speed of processing, anticipation, inhibition and working memory in bilinguals.

    PubMed

    Bonifacci, Paola; Giombini, Lucia; Bellocchi, Stéphanie; Contento, Silvana

    2011-03-01

    Literature on the so-called bilingual advantage is directed towards the investigation of whether the mastering of two languages fosters cognitive skills in the non-verbal domain. The present study aimed to evaluate whether the bilingual advantage in non-verbal skills could be best defined as domain-general or domain-specific, and, in the latter case, at identifying the basic cognitive skills involved. Bilingual and monolingual participants were divided into two different age groups (children, youths) and were tested on a battery of elementary cognitive tasks which included a choice reaction time task, a go/no-go task, two working memory tasks (numbers and symbols) and an anticipation task. Bilingual and monolingual children did not differ from each other except for the anticipation task, where bilinguals were found to be faster and more accurate than monolinguals. These findings suggest that anticipation, which has received little attention to date, is an important cognitive domain which needs to be evaluated to a greater extent both in bilingual and monolingual participants. PMID:22213899

  7. Individual Differences in Eye-Movements During Reading: Working Memory and Speed-of-Processing Effects

    PubMed Central

    Traxler, Matthew J.; Long, Debra L.; Tooley, Kristen M.; Johns, Clinton L.; Zirnstein, Megan; Jonathan, Eunike

    2015-01-01

    Theories of eye-movement control in reading should ultimately describe how differences in knowledge and cognitive abilities affect reading and comprehension. Current mathematical models of eye-movement control do not yet incorporate individual differences as a source of variation in reading, although developmental and group-difference effects have been studied. These models nonetheless provide an excellent foundation for describing and explaining how and why patterns of eye-movements differ across readers (e.g., Rayner, Chace, & Ashby, 2006). Our focus in this article is on two aspects of individual variation: global processing speed (e.g., Salthouse, 1996) and working-memory capacity (e.g., Just & Carpenter, 1992). Using Hierarchical Linear Modeling (HLM) (Raudenbush & Bryk, 2001), we tested the extent to which overall reading speed and working-memory capacity moderate the degree to which syntactic and semantic information affect fixation times. Previous published data (Traxler et al., 2005) showed that working memory capacity and syntactic complexity interacted to determine fixation times in an eye-movement monitoring experiment. In a new set of models based on this same data set, we found that working-memory capacity interacted with sentence-characteristic variables only when processing speed was not included in the model. We interpret these findings with respect to current accounts of sentence processing and suggest how they might be incorporated into eye-movement control models.

  8. Effects of age, speed of processing, and working memory on comprehension of sentences with relative clauses.

    PubMed

    Caplan, David; Dede, Gayle; Waters, Gloria; Michaud, Jennifer; Tripodis, Yorghos

    2011-06-01

    Two hundred participants, 50 in each of four age ranges (19-29, 30-49, 50-69, 70-90) were tested for working memory, speed of processing, and the processing of sentences with relative clauses. In Experiment 1, participants read four sentence types (cleft subject, cleft object, subject-subject, subject-object) in a word-by-word, non-cumulative, self-paced reading task and made speeded plausibility judgments about them. In Experiment 2, participants read two types of sentences, one of which contained a doubly center embedded relative clause. Older participants' comprehension was less accurate and there was age-related slowing of online processing times in all but the simplest sentences, which increased in syntactically complex sentences in Experiment 1. This pattern suggests an age-related decrease in the efficiency of parsing and interpretation. Slower speed of processing and lower working memory were associated with longer online processing times only in Experiment 2, suggesting that task-related operations are related to general speed of processing and working memory. Lower working memory was not associated with longer reading times in more complex sentences, consistent with the view that general working memory is not critically involved in online syntactic processing. Longer online processing at the most demanding point in the most demanding sentence was associated with better comprehension, indicating that it reflects effective processing under some certain circumstances. However, the poorer comprehension performance of older individuals indicates that their slower online processing reflects inefficient processing even at these points. PMID:21480714

  9. Magnetically aligned carbon nanotube in nanopaper enabled shape-memory nanocomposite for high speed electrical actuation

    NASA Astrophysics Data System (ADS)

    Lu, Haibao; Gou, Jihua; Leng, Jinsong; Du, Shanyi

    2011-04-01

    A new shape-memory nanocomposite that exhibits rapid electrical actuation capabilities is fabricated by incorporating self-assembly multiwalled carbon nanotube (MWCNT) nanopaper and magnetic CNTs into a styrene-based shape-memory polymer (SMP). The MWCNT nanopaper was coated on the surface to give high electrical conductivity to SMP. Electromagnetic CNTs were blended with and, vertically aligned into the SMP resin upon a magnetic field, to facilitate the heat transfer from the nanopaper to the underlying SMP. This not only significantly enhances heat transfer but also gives high speed electrical actuation.

  10. Delayed Perceptual Awareness in Rapid Perceptual Decisions

    PubMed Central

    Gregori-Grgi?, Regina; Balderi, Monica; de'Sperati, Claudio

    2011-01-01

    The flourishing of studies on the neural correlates of decision-making calls for an appraisal of the relation between perceptual decisions and conscious perception. By exploiting the long integration time of noisy motion stimuli, and by forcing human observers to make difficult speeded decisions – sometimes a blind guess – about stimulus direction, we traced the temporal buildup of motion discrimination capability and perceptual awareness, as assessed trial by trial through direct rating. We found that both increased gradually with motion coherence and viewing time, but discrimination was systematically leading awareness, reaching a plateau much earlier. Sensitivity and criterion changes contributed jointly to the slow buildup of perceptual awareness. It made no difference whether motion discrimination was accomplished by saccades or verbal responses. These findings suggest that perceptual awareness emerges on the top of a developing or even mature perceptual decision. We argue that the middle temporal (MT) cortical region does not confer us the full phenomenic depth of motion perception, although it may represent a precursor stage in building our subjective sense of visual motion. PMID:21379582

  11. Radiation Hardened High-Density Memory, High Speed Memory Controllers, Data Busses

    E-print Network

    Busses Technologies for Unmanned Atmospheric Platforms Technical Abstract While VPX shows promise as an open standard COTS computing and memory platform, there are several challenges that must be overcome, modular dropsonde launcher is being developed for Unmanned Aerial Vehicles (UAVs). Some critical

  12. Association of acousto-optic and micro-scanning mirrors for diffractive memory high speed reading

    Microsoft Academic Search

    Renaud Kiefer; Y. Takakura; J. Fontaine; El Hafidi; P. C. Montgomery; P. Meyrueis

    2003-01-01

    We present an investigation that has been carried out on the design of a high speed scanning system for a data storage application. Polypeptide material is used to store data by the angular multiplexing process. This material presents many advantages compared with others. To address the optical memory, our set-up is composed of micro-scanning mirrors (MEMS) and an acousto-optic deflector

  13. GaAs MESFET SRAM using a New High Speed Memory Cell

    Microsoft Academic Search

    A. Bernal; R. P. Ribas; A. Guyot

    1997-01-01

    This paper presents an experimental 1kb GaAs MESFET static RAM using a novel high speed memory cell. The array overcomes the subthreshold leakage currents drawbacks inherent to conventional cell using a particular word\\/bit lines biasing. Power consumption is reduced by powering down the parts of the array not selected. An address access time of 1ns with 20 ?A\\/cell power consumption

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

    PubMed Central

    Zhang, Jiaxiang; Rowe, James B.

    2014-01-01

    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

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

    Microsoft Academic Search

    Yu-Cheng Fan; Ta-Che Lo

    2009-01-01

    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

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

    ERIC Educational Resources Information Center

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

    2013-01-01

    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,…

  17. Microwave synthesis and actuation of shape memory polycaprolactone foams with high speed.

    PubMed

    Zhang, Fenghua; Zhou, Tianyang; Liu, Yanju; Leng, Jinsong

    2015-01-01

    Microwave technology is a highly effective approach to fast and uniform heating. This article investigates that the microwave heating as a novel method is used to rapidly foam and actuate biocompatible and biodegradable shape memory crosslinked-polycaprolactone (c-PCL) foams. The optical microscope proves that the resulting c-PCL foams have homogenous pore structure. Mechanical behavior and shape memory performance of c-PCL foams are investigated by static materials testing. Shape recovery ratio is approximately 100% and the whole recovery process takes only 98?s when trigged by microwave. Due to the unique principle of microwave heating, the recovery speed of c-PCL foams in microwave oven is several times faster than that in hot water and electric oven. Hence compared to the traditional heating methods, microwave is expected to bring more advantages to modern industry and scientific research in the field of smart materials and structures. PMID:26053586

  18. Microwave synthesis and actuation of shape memory polycaprolactone foams with high speed

    PubMed Central

    Zhang, Fenghua; Zhou, Tianyang; Liu, Yanju; Leng, Jinsong

    2015-01-01

    Microwave technology is a highly effective approach to fast and uniform heating. This article investigates that the microwave heating as a novel method is used to rapidly foam and actuate biocompatible and biodegradable shape memory crosslinked-polycaprolactone (c-PCL) foams. The optical microscope proves that the resulting c-PCL foams have homogenous pore structure. Mechanical behavior and shape memory performance of c-PCL foams are investigated by static materials testing. Shape recovery ratio is approximately 100% and the whole recovery process takes only 98?s when trigged by microwave. Due to the unique principle of microwave heating, the recovery speed of c-PCL foams in microwave oven is several times faster than that in hot water and electric oven. Hence compared to the traditional heating methods, microwave is expected to bring more advantages to modern industry and scientific research in the field of smart materials and structures. PMID:26053586

  19. Perceptual-Cognitive Expertise in Elite Volleyball Players

    PubMed Central

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

    2013-01-01

    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

  20. Auditory perceptual consolidation in early-onset blindness.

    PubMed

    Stevens, Alexander A; Weaver, Kurt

    2005-01-01

    Early-onset blindness (EB) produces measurable advantages in auditory perception, attention, memory and language. Neville and Bavelier [Neville, H. J., & Bavelier, D. (2001) Variability of developmental plasticity. In J. L. McClelland, R. S. Siegler (Eds.) Mechanisms of cognitive development: Behavioral andellon symposia on cognition (pp. 271-301)] hypothesized that faster temporal processing underlies many auditory compensatory effects in the blind. We tested this hypothesis by comparing early-onset blind individuals and sighted counterparts (SC) by assessing their rates of perceptual consolidation, the accurate perceptual representation of auditory stimuli. Firstly, we first tested both groups on a temporal-order judgment task (TOJ). EB subjects had significantly lower TOJ thresholds than the SC subjects. Secondly, we assessed perceptual consolidation speed using auditory backward masking tasks, taking into account individual TOJ thresholds. Discrimination performance was unaffected at all mask delays in the EB group while the SC subjects needed a mask delay of 160 ms to perform comparably. A backward masking task using single tone stimuli found no differences between the EB and SC groups any mask delay. A simultaneous masking task demonstrated that the mask effectively impaired discrimination in EB subjects at sensory stages. These results suggest that advantages in perceptual consolidation may reflect a mechanism responsible for the short response times and better performance reported in early blind individuals across a number of complex auditory tasks. PMID:15869766

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

    ERIC Educational Resources Information Center

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

    2005-01-01

    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,…

  2. Self-Construal Priming Affects Speed of Retrieval from Short-Term Memory

    PubMed Central

    MacDonald, Justin A.; Sandry, Joshua; Rice, Stephen

    2012-01-01

    We investigated the effects of collective or individual self-construal priming on recall in a short-term memory (STM) task. We primed participants to either their individual or their collective self-construals or a neutral control condition. Participants then completed a STM retrieval task using either random or patterned digit strings. Findings revealed that priming an individual self-construal resulted in faster retrieval of information from STM for both stimulus types. These results indicate that individual self-accessibility improves retrieval speed of digits from STM, regardless of set configuration. More broadly, the present findings extend prior research by adding further evidence of the effects of self-construal priming on cognitive information processing. PMID:23209632

  3. Comprehension of Linguistic Dependencies: Speed-Accuracy Tradeoff Evidence for Direct-Access Retrieval From Memory

    PubMed Central

    Foraker, Stephani; McElree, Brian

    2012-01-01

    Comprehenders can rapidly and efficiently interpret expressions with various types of non-adjacent dependencies. In the sentence The boy that the teacher warned fell, boy is readily interpreted as the subject of the verb fall despite the fact that a relative clause, that the teacher warned, intervenes between the two dependent elements. We review research investigating three memory operations proposed for resolving this and other types of non-adjacent dependencies: serial search retrieval, in which the dependent constituent is recovered by a search process through representations in memory, direct-access retrieval in which the dependent constituent is recovered directly by retrieval cue operations without search, and active maintenance of the dependent constituent in focal attention. Studies using speed-accuracy tradeoff methodology to examine the full timecourse of interpreting a wide range of non-adjacent dependencies indicate that comprehenders retrieve dependent constituents with a direct-access operation, consistent with the claim that representations formed during comprehension are accessed with a cue-driven, content-addressable retrieval process. The observed timecourse profiles are inconsistent with a broad class of models based on several search operations for retrieval. The profiles are also inconsistent with active maintenance of a constituent while concurrently processing subsequent material, and suggest that, with few exceptions, direct-access retrieval is required to process non-adjacent dependencies. PMID:22448181

  4. Measures of Working Memory Span and Verbal Rehearsal Speed in Deaf Children after Cochlear Implantation

    PubMed Central

    Pisoni, David B.; Cleary, Miranda

    2012-01-01

    Large individual differences in spoken word recognition performance have been found in deaf children after cochlear implantation. Recently, Pisoni and Geers (2000) reported that simple forward digit span measures of verbal working memory were significantly correlated with spoken word recognition scores even after potentially confounding variables were statistically controlled for. The present study replicates and extends these initial findings to the full set of 176 participants in the CID cochlear implant study. The pooled data indicate that despite statistical “partialling-out” of differences in chronological age, communication mode, duration of deafness, duration of device use, age at onset of deafness, number of active electrodes, and speech feature discrimination, significant correlations still remain between digit span and several measures of spoken word recognition. Strong correlations were also observed between speaking rate and both forward and backward digit span, a result that is similar to previously reported findings in normalhearing adults and children. The results suggest that perhaps as much as 20% of the currently unexplained variance in spoken word recognition scores may be independently accounted for by individual differences in cognitive factors related to the speed and efficiency with which phonological and lexical representations of spoken words are maintained in and retrieved from working memory. A smaller percentage, perhaps about 7% of the currently unexplained variance in spoken word recognition scores, may be accounted for in terms of working memory capacity. We discuss how these relationships may arise and their contribution to subsequent speech and language development in prelingually deaf children who use cochlear implants. PMID:12612485

  5. Stochastic accumulation of feature information in perception and memory

    PubMed Central

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

    2014-01-01

    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

  6. Stochastic accumulation of feature information in perception and memory.

    PubMed

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

    2014-01-01

    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

  7. Reference effets -1-Asymmetries in Categorization, Perceptual Discrimination, and Visual Search for Reference and

    E-print Network

    Indiana University

    Reference effets -1- Asymmetries in Categorization, Perceptual Discrimination, and Visual Search;Reference effets -3- Asymmetries in Categorization, Perceptual Discrimination, and Visual Search; Livingston, Andrews, & Harnad, 1999) and addressed the consequences of this bias for memory (e.g., Corneille

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

    NASA Astrophysics Data System (ADS)

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

    2010-07-01

    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.

  9. Processing Speed, Attention, and Working Memory After Treatment for Medulloblastoma: An International, Prospective, and Longitudinal Study

    PubMed Central

    Palmer, Shawna L.; Armstrong, Carol; Onar-Thomas, Arzu; Wu, Shengjie; Wallace, Dana; Bonner, Melanie J.; Schreiber, Jane; Swain, Michelle; Chapieski, Lynn; Mabbott, Donald; Knight, Sarah; Boyle, Robyn; Gajjar, Amar

    2013-01-01

    Purpose The current study prospectively examined processing speed (PS), broad attention (BA), and working memory (WM) ability of patients diagnosed with medulloblastoma over a 5-year period. Patients and Methods The study included 126 patients, ages 3 to 21 years at diagnosis, enrolled onto a collaborative protocol for medulloblastoma. Patients were treated with postsurgical risk-adapted craniospinal irradiation (n = 36 high risk [HR]; n = 90 average risk) followed by four cycles of high-dose chemotherapy with stem-cell support. Patients completed 509 neuropsychological evaluations using the Woodcock-Johnson Tests of Cognitive Abilities Third Edition (median of three observations per patient). Results Linear mixed effects models revealed that younger age at diagnosis, HR classification, and higher baseline scores were significantly associated with poorer outcomes in PS. Patients treated as HR and those with higher baseline scores are estimated to have less favorable outcomes in WM and BA over time. Parent education and marital status were significantly associated with BA and WM baseline scores but not change over time. Conclusion Of the three key domains, PS was estimated to have the lowest scores at 5 years after diagnosis. Identifying cognitive domains most vulnerable to decline should guide researchers who are aiming to develop efficacious cognitive intervention and rehabilitation programs, thereby improving the quality of survivorship for the pediatric medulloblastoma population. PMID:23980078

  10. An exemplar-based random walk model of speeded classification

    Microsoft Academic Search

    Robert M. Nosofsky; Thomas J. Palmeri

    1997-01-01

    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

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

    PubMed Central

    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

    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

  12. Dissociation of rapid response learning and facilitation in perceptual and conceptual networks of person recognition.

    PubMed

    Valt, Christian; Klein, Christoph; Boehm, Stephan G

    2015-08-01

    Repetition priming is a prominent example of non-declarative memory, and it increases the accuracy and speed of responses to repeatedly processed stimuli. Major long-hold memory theories posit that repetition priming results from facilitation within perceptual and conceptual networks for stimulus recognition and categorization. Stimuli can also be bound to particular responses, and it has recently been suggested that this rapid response learning, not network facilitation, provides a sound theory of priming of object recognition. Here, we addressed the relevance of network facilitation and rapid response learning for priming of person recognition with a view to advance general theories of priming. In four experiments, participants performed conceptual decisions like occupation or nationality judgments for famous faces. The magnitude of rapid response learning varied across experiments, and rapid response learning co-occurred and interacted with facilitation in perceptual and conceptual networks. These findings indicate that rapid response learning and facilitation in perceptual and conceptual networks are complementary rather than competing theories of priming. Thus, future memory theories need to incorporate both rapid response learning and network facilitation as individual facets of priming. PMID:25291047

  13. Brain Training Game Boosts Executive Functions, Working Memory and Processing Speed in the Young Adults: A Randomized Controlled Trial

    PubMed Central

    Nouchi, Rui; Taki, Yasuyuki; Takeuchi, Hikaru; Hashizume, Hiroshi; Nozawa, Takayuki; Kambara, Toshimune; Sekiguchi, Atsushi; Miyauchi, Carlos Makoto; Kotozaki, Yuka; Nouchi, Haruka; Kawashima, Ryuta

    2013-01-01

    Background Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults. Methods We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability). Results and Discussion Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults. Conclusions Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields. Trial Registration UMIN Clinical Trial Registry 000005618. PMID:23405164

  14. Novel Co-Design of NAND Flash Memory and NAND Flash Controller Circuits for Sub30 nm Low-Power High-Speed Solid-State Drives (SSD)

    Microsoft Academic Search

    Ken Takeuchi

    2009-01-01

    As the cell size of the NAND flash memory has been scaled down by 40%-50% per year and the memory capacity has been doubling every year, a solid-state drive (SSD) that uses NAND as mass storage for personal computers and enterprise servers is attracting much attention. To realize a low-power high-speed SSD, the co-design of NAND flash memory and NAND

  15. Architecture Support for High Speed Protection of Memory Integrity and Confidentiality in Symmetric Multiprocessor Systems

    Microsoft Academic Search

    Weidong Shi; H. H. Sean Lee; Mrinmoy Ghosh; Chenghuai Lu; Tao Zhang

    Recently there is a growing interest in both the architecture and the security community to create a hardware based so- lution for authenticating system memory. As shown in the previous work, such silicon based memory authentication could become a vital component for creating future trusted computing environments and digital rights protection. Al- most all the published work have focused on

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

    DOEpatents

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

    1989-01-01

    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.

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

    Microsoft Academic Search

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

    2007-01-01

    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

  18. Cache Memories

    Microsoft Academic Search

    Alan Jay Smith

    1982-01-01

    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

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

    ERIC Educational Resources Information Center

    Nosofsky, Robert M.; Stanton, Roger D.

    2006-01-01

    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…

  20. Individual Differences in Amygdala Activity Predict Response Speed during Working Memory

    PubMed Central

    Schaefer, Alexandre; Braver, Todd S.; Reynolds, Jeremy R.; Burgess, Gregory C.; Yarkoni, Tal; Gray, Jeremy R.

    2007-01-01

    The human amygdala has classically been viewed as a brain structure primarily related to emotions and dissociated from higher cognition. We report here findings suggesting that the human amygdala also has a role in supporting working memory (WM), a canonical higher cognitive function. In a first functional magnetic resonance imaging (fMRI) study (n = 53), individual differences in amygdala activity predicted behavioral performance in a 3-back WM task. Specifically, higher event-related amygdala amplitude predicted faster response time (RT; r = ?0.64), with no loss of accuracy. This relationship was not contingent on mood state, task content, or personality variables. In a second fMRI study (n = 21), we replicated the key finding (r = ?0.47) and further showed that the correlation between the amygdala and faster RT was specific to a high working memory load condition (3-back) compared with a low working memory load condition (1-back). These results support models of amygdala function that can account for its involvement not only in emotion but also higher cognition. PMID:17021168

  1. High Speed Robust Current Sense Amplifier for Nanoscale Memories: - A Winner Take All Approach

    Microsoft Academic Search

    Srikanth Sundaram; Praveen Elakkumanan; Ramalingam Sridhar

    2006-01-01

    The design of fast, low power and robust sense amplifier circuits is a challenge for nanoscale SRAMs due to the increasing bit line capacitance and process variations. Current sensing in SRAMs is promising to achieve high-speed operation in low-voltage application. In this paper, we propose a process variation tolerant, high performance and scalable current sense amplifier that uses a winner

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

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

    Microsoft Academic Search

    Thomas L. Martin; Daniel P. Siewiorek

    1999-01-01

    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

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

    PubMed

    Etherton, Joseph

    2014-01-01

    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

  5. Non-volatile, high density, high speed, Micromagnet-Hall effect Random Access Memory (MHRAM)

    NASA Technical Reports Server (NTRS)

    Wu, Jiin C.; Katti, Romney R.; Stadler, Henry L.

    1991-01-01

    The micromagnetic Hall effect random access memory (MHRAM) has the potential of replacing ROMs, EPROMs, EEPROMs, and SRAMs because of its ability to achieve non-volatility, radiation hardness, high density, and fast access times, simultaneously. Information is stored magnetically in small magnetic elements (micromagnets), allowing unlimited data retention time, unlimited numbers of rewrite cycles, and inherent radiation hardness and SEU immunity, making the MHRAM suitable for ground based as well as spaceflight applications. The MHRAM device design is not affected by areal property fluctuations in the micromagnet, so high operating margins and high yield can be achieved in large scale integrated circuit (IC) fabrication. The MHRAM has short access times (less than 100 nsec). Write access time is short because on-chip transistors are used to gate current quickly, and magnetization reversal in the micromagnet can occur in a matter of a few nanoseconds. Read access time is short because the high electron mobility sensor (InAs or InSb) produces a large signal voltage in response to the fringing magnetic field from the micromagnet. High storage density is achieved since a unit cell consists only of two transistors and one micromagnet Hall effect element. By comparison, a DRAM unit cell has one transistor and one capacitor, and a SRAM unit cell has six transistors.

  6. Specificity of perceptual processing in rereading spatially transformed materials.

    PubMed

    Horton, K D; McKenzie, B D

    1995-05-01

    While most studies using the task of reading spatially transformed text do not reveal evidence of specific perceptual transfer, a study by Masson (1986, Experiment 3) provides clear evidence of such effects. Several experiments were designed to identify the basis for this empirical discrepancy. The only substantive evidence of specific perceptual transfer occurred when the words were presented in an unfamiliar typography, although each study suggested a trend toward perceptual specificity effects. The results are discussed in terms of Graf and Ryan's (1990) ideas about the role of distinctive memory representations. PMID:7791597

  7. "The Mask Who Wasn't There": Visual Masking Effect with the Perceptual Absence of the Mask

    ERIC Educational Resources Information Center

    Rey, Amandine Eve; Riou, Benoit; Muller, Dominique; Dabic, Stéphanie; Versace, Rémy

    2015-01-01

    Does a visual mask need to be perceptually present to disrupt processing? In the present research, we proposed to explore the link between perceptual and memory mechanisms by demonstrating that a typical sensory phenomenon (visual masking) can be replicated at a memory level. Experiment 1 highlighted an interference effect of a visual mask on the…

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

    PubMed

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

    2011-12-01

    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

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

    NASA Astrophysics Data System (ADS)

    Eskil, Murat; Kanca, Erdogan

    2013-09-01

    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.

  10. Hafnium aluminum oxide as charge storage and blocking-oxide layers in SONOS-type nonvolatile memory for high-speed operation

    Microsoft Academic Search

    Yan Ny Tan; W. K. Chim; Wee Kiong Choi; Moon Sig Joo; Byung Jin Cho

    2006-01-01

    The charge storage and program\\/erase mechanisms in polysilicon-oxide-nitride-oxide-silicon (SONOS) memory structures with charge-storage layers of different materials are investigated in this paper. In particular, the use of a HfAlO charge-storage layer in a SONOS-type memory structure is proposed. Compared to other high-? charge-storage layers, HfAlO has the advantage of high-speed program\\/erase of HfO2 as well as the good charge-retention time

  11. Perceptual Image Distortion

    Microsoft Academic Search

    Patrick C. Teo; David J. Heeger

    1994-01-01

    In this paper, we present a perceptual distortion measure that predicts image integrity far better than mean-squared error. This perceptual distortion measure is based on a model of human visual processing that fits empirical measurements of: (1) the response properties of neurons in the primary visual cortex, and (2) the psychophysics of spatial pattern detection. We also illustrate the usefulness

  12. Frequent video game players resist perceptual interference.

    PubMed

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

    2015-01-01

    Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT), a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning. PMID:25807394

  13. Hemispheric Laterality and Memory Bias for Threat in Anxiety Disorders

    Microsoft Academic Search

    2000-01-01

    The authors examined auditory perceptual asymmetries and explicit memory biases for threat in patients with panic disorder and generalized anxiety disorder relative to healthy control subjects. They did not find a greater explicit memory bias for threat in the anxiety patients. However, explicit memory biases for threat were associated with perceptual asymmetry scores; patients with a greater right-ear (left hemisphere)

  14. Speed: 131.3G flops (4Grape6 VLSI Chips 6Pipeline per chip). Memory size: 262,144 particle. (18Mbit Burst-SRAM8)

    E-print Network

    Kissler-Patig, Markus

    · Speed: 131.3G flops (4×Grape6 VLSI Chips 6Pipeline per chip). · Memory size: 262,144 particle Power consumption : DC12V 5A, ATX power supply Grape6-BLX64 is an upgrade model of Micro Grape. It is special for built-in cluster. It is 30 percent faster than Micro GRAPE by using 64bit/100MHz PCI

  15. 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

    A M M Vlaar; D T Wade

    2003-01-01

    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

  16. 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

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

    2012-01-01

    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…

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

    PubMed

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

    2015-04-01

    Recent neuropsychological theories emphasize the influence of maladaptive learning and memory processes on pain perception. However, the precise relationship between these processes as well as the underlying mechanisms remain poorly understood; especially the role of perceptual discrimination and its modulation by associative fear learning has received little attention so far. Experimental work with exteroceptive stimuli consistently points to effects of fear learning on perceptual discrimination acuity. In addition, clinical observations have revealed that in individuals with chronic pain perceptual discrimination is impaired, and that tactile discrimination training reduces pain. Based on these findings, we present a theoretical model of which the central tenet is that associative fear learning contributes to the development of chronic pain through impaired interoceptive and proprioceptive discrimination acuity. PMID:25603316

  18. Brief Daily Exposures to Asian Females Reverses Perceptual Narrowing for Asian Faces in Caucasian Infants

    ERIC Educational Resources Information Center

    Anzures, Gizelle; Wheeler, Andrea; Quinn, Paul C.; Pascalis, Olivier; Slater, Alan M.; Heron-Delaney, Michelle; Tanaka, James W.; Lee, Kang

    2012-01-01

    Perceptual narrowing in the visual, auditory, and multisensory domains has its developmental origins during infancy. The current study shows that experimentally induced experience can reverse the effects of perceptual narrowing on infants' visual recognition memory of other-race faces. Caucasian 8- to 10-month-olds who could not discriminate…

  19. Implicit Memory in Monkeys: Development of a Delay Eyeblink Conditioning System with Parallel Electromyographic and High-Speed Video Measurements.

    PubMed

    Kishimoto, Yasushi; Yamamoto, Shigeyuki; Suzuki, Kazutaka; Toyoda, Haruyoshi; Kano, Masanobu; Tsukada, Hideo; Kirino, Yutaka

    2015-01-01

    Delay eyeblink conditioning, a cerebellum-dependent learning paradigm, has been applied to various mammalian species but not yet to monkeys. We therefore developed an accurate measuring system that we believe is the first system suitable for delay eyeblink conditioning in a monkey species (Macaca mulatta). Monkey eyeblinking was simultaneously monitored by orbicularis oculi electromyographic (OO-EMG) measurements and a high-speed camera-based tracking system built around a 1-kHz CMOS image sensor. A 1-kHz tone was the conditioned stimulus (CS), while an air puff (0.02 MPa) was the unconditioned stimulus. EMG analysis showed that the monkeys exhibited a conditioned response (CR) incidence of more than 60% of trials during the 5-day acquisition phase and an extinguished CR during the 2-day extinction phase. The camera system yielded similar results. Hence, we conclude that both methods are effective in evaluating monkey eyeblink conditioning. This system incorporating two different measuring principles enabled us to elucidate the relationship between the actual presence of eyelid closure and OO-EMG activity. An interesting finding permitted by the new system was that the monkeys frequently exhibited obvious CRs even when they produced visible facial signs of drowsiness or microsleep. Indeed, the probability of observing a CR in a given trial was not influenced by whether the monkeys closed their eyelids just before CS onset, suggesting that this memory could be expressed independently of wakefulness. This work presents a novel system for cognitive assessment in monkeys that will be useful for elucidating the neural mechanisms of implicit learning in nonhuman primates. PMID:26068663

  20. Implicit Memory in Monkeys: Development of a Delay Eyeblink Conditioning System with Parallel Electromyographic and High-Speed Video Measurements

    PubMed Central

    Suzuki, Kazutaka; Toyoda, Haruyoshi; Kano, Masanobu; Tsukada, Hideo; Kirino, Yutaka

    2015-01-01

    Delay eyeblink conditioning, a cerebellum-dependent learning paradigm, has been applied to various mammalian species but not yet to monkeys. We therefore developed an accurate measuring system that we believe is the first system suitable for delay eyeblink conditioning in a monkey species (Macaca mulatta). Monkey eyeblinking was simultaneously monitored by orbicularis oculi electromyographic (OO-EMG) measurements and a high-speed camera-based tracking system built around a 1-kHz CMOS image sensor. A 1-kHz tone was the conditioned stimulus (CS), while an air puff (0.02 MPa) was the unconditioned stimulus. EMG analysis showed that the monkeys exhibited a conditioned response (CR) incidence of more than 60% of trials during the 5-day acquisition phase and an extinguished CR during the 2-day extinction phase. The camera system yielded similar results. Hence, we conclude that both methods are effective in evaluating monkey eyeblink conditioning. This system incorporating two different measuring principles enabled us to elucidate the relationship between the actual presence of eyelid closure and OO-EMG activity. An interesting finding permitted by the new system was that the monkeys frequently exhibited obvious CRs even when they produced visible facial signs of drowsiness or microsleep. Indeed, the probability of observing a CR in a given trial was not influenced by whether the monkeys closed their eyelids just before CS onset, suggesting that this memory could be expressed independently of wakefulness. This work presents a novel system for cognitive assessment in monkeys that will be useful for elucidating the neural mechanisms of implicit learning in nonhuman primates. PMID:26068663

  1. Perceptually oriented hypnosis.

    PubMed

    Woodard, Fredrick J

    2003-04-01

    This theoretical article explores postulates representative of a perceptual frame of reference for a better understanding of hypnotic experiencing. This author contends that Perceptual Psychology, a theory first conceptualized by Snygg and Combs, as revised by Combs, Richards, and Richards in 1988, and Perceptually Oriented Hypnosis provide an effective way of understanding hypnosis, the therapist-client relationship, and has some implications as well for better comprehending psychopathology. Perceptually oriented hypnotic principles are shown to enhance the characeristics of the adequate personality, expand the phenomenal field, change personal meanings, and change aspects of the phenomenal self in the context of hypnosis. Implications for understanding differing views and conflicting perceptions of reality held by scientists and researchers are discussed. Implications for Dissociative Identity Disorder are also addressed. Research utilizing Giorgi's research methodology and Wasicsko's qualitative procedure for assessing educators' dispositions is suggested. PMID:12785635

  2. Perceptually Near Pawlak Partitions

    NASA Astrophysics Data System (ADS)

    Ramanna, Sheela

    The problem considered in this paper is how to compare perceptually indiscernible partitions of disjoint, non-empty sets such as pairs of digital images viewed as sets of points. Such partitions are called perceptual Pawlak partitions, named after Z. Pawlak, who introduced a attribute-based equivalence relation in 1981 (the well-known indiscernibility relation from rough set theory). The solution to the problem stems from an approach to pairwise comparison reminiscent of the G. Fechner's 1860 approach to comparing perceptions in psychophysics experiments. For Fechner, one perception of an object is indistinguishable from the perception of a different object, if there is no perceptible difference in the particular sensed feature value of the objects, e.g., perceptions resulting from lifting small objects where the object feature is weight. In comparing visual perceptions, partitions of images determined by a particular form of indiscernibility relation ˜{}_{B} are used. The L1 (Manhattan distance) norm form of what is known as a perceptual indiscernibility relation defined within the context of a perceptual system is used in this article to define what are known as perceptually indiscernible Pawlak partitions (PIPs). An application of PIPs and near sets is given in this article in terms of a new form of content-based image retrieval (CBIR). This article investigates the efficacy of perceptual CBIR using Hausdorff and Mahalanobis distance measures to determine the degree of correspondence between pairs of perceptual Pawlak partitions of digital images. The contribution of this article is the introduction of an approach to comparing perceptually indiscernible image partitions.

  3. Implicit Recognition Based on Lateralized Perceptual Fluency

    PubMed Central

    Vargas, Iliana M.; Voss, Joel L.; Paller, Ken A.

    2012-01-01

    In some circumstances, accurate recognition of repeated images in an explicit memory test is driven by implicit memory. We propose that this “implicit recognition” results from perceptual fluency that influences responding without awareness of memory retrieval. Here we examined whether recognition would vary if images appeared in the same or different visual hemifield during learning and testing. Kaleidoscope images were briefly presented left or right of fixation during divided-attention encoding. Presentation in the same visual hemifield at test produced higher recognition accuracy than presentation in the opposite visual hemifield, but only for guess responses. These correct guesses likely reflect a contribution from implicit recognition, given that when the stimulated visual hemifield was the same at study and test, recognition accuracy was higher for guess responses than for responses with any level of confidence. The dramatic difference in guessing accuracy as a function of lateralized perceptual overlap between study and test suggests that implicit recognition arises from memory storage in visual cortical networks that mediate repetition-induced fluency increments. PMID:24962684

  4. Design of all-dc-powered high-speed single flux quantum random access memory based on a pipeline structure for memory cell arrays

    Microsoft Academic Search

    Shuichi Nagasawa; Kenji Hinode; Tetsuro Satoh; Yoshihiro Kitagawa; Mutsuo Hidaka

    2006-01-01

    We designed a superconducting random access memory (RAM) in which all component circuits can be operated with dc-bias currents. A dc-powered superconducting loop driver and a dc-powered sense circuit are effectively combined with single flux quantum (SFQ) circuits. We proposed a pipeline structure for the memory cell array composed of the dc-powered loop drivers, the dc-powered sense circuits, passive transmission

  5. Working Memory Capacity in a Go/No-Go Task: Age Differences in Interference, Processing Speed, and Attentional Control

    ERIC Educational Resources Information Center

    Rodríguez-Villagra, Odir Antonio; Göthe, Katrin; Oberauer, Klaus; Kliegl, Reinhold

    2013-01-01

    We tested the limits of working-memory capacity (WMC) of young adults, old adults, and children with a memory-updating task. The task consisted of mentally shifting spatial positions within a grid according to arrows, their color signaling either only go (control) or go/no-go conditions. The interference model (IM) of Oberauer and Kliegl (2006)…

  6. Perceptual processing affects the reactivation of a sensory dimension during a categorization task.

    PubMed

    Riou, Benoit; Rey, Amandine E; Vallet, Guillaume T; Cuny, Caroline; Versace, Rémy

    2015-06-01

    According to grounded theories of cognition, knowledge is grounded in its sensory-motor features. Therefore, perceptual and conceptual processing should be based on the same distributed system so that conceptual and perceptual processes should interact. The present study assesses whether gustatory stimulation (participants tasted a sweet or a nonsweet yoghurt) could influence performance on a categorization task that involves the reactivation of the same sensory dimension. The results indicate that participants were slower (Experiment 1) or faster (Experiment 2), respectively, at categorizing pictures as representing edible sweet stimuli when they either simultaneously or had previously tasted a sweet yoghurt as compared to a nonsweet yoghurt. These results confirm the significant overlap between perceptual and memory mechanisms and suggest the functional equivalence between perceptually present and perceptually absent (memory reactivated) dimensions. PMID:25409625

  7. Perceptual skill in soccer: Implications for talent identification and development

    Microsoft Academic Search

    A. M. Williams

    2000-01-01

    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

  8. Attentional Modulation of Perceptual Comparison for Feature Binding

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  9. Perceptual Centers (P-centers)

    ERIC Educational Resources Information Center

    Morton, John; And Others

    1976-01-01

    Words presented with regular acoustic onsets are not "perceptually" regular. The requirements for perceived regularity were investigated, and the "perceptual center" (P-center) of a word was defined as its psychological moment of occurrence. (Editor)

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

    PubMed Central

    Streb, Markus; Pfaltz, Monique; Michael, Tanja

    2014-01-01

    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

  11. Perceptual decision making in less than 30 milliseconds

    PubMed Central

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

    2010-01-01

    In perceptual discrimination tasks, a subject’s response time is determined both by sensory and motor processes. Measuring the time consumed by the perceptual evaluation step alone is thus complicated by factors such as motor preparation, task difficulty and speed-accuracy tradeoffs. Here we present a task design that minimizes these confounds and allows us to track a subject’s perceptual performance with unprecedented temporal resolution. We find that monkeys can make accurate color discriminations in less than 30 ms. Furthermore, our simple task design provides a novel tool for elucidating how neuronal activity relates to sensory versus motor processing, as demonstrated with neural data from cortical oculomotor neurons. In these cells, perceptual information acts by accelerating and decelerating the ongoing motor plans associated with correct and incorrect choices, as predicted by a race-to-threshold model, and the time course of these neural events parallels the time course of the subject's choice accuracy. PMID:20098418

  12. Fusing Functional MRI and Diffusion Tensor Imaging Measures of Brain Function and Structure to Predict Working Memory and Processing Speed Performance among Inter-episode Bipolar Patients.

    PubMed

    McKenna, Benjamin S; Theilmann, Rebecca J; Sutherland, Ashley N; Eyler, Lisa T

    2015-05-01

    Evidence for abnormal brain function as measured with diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) and cognitive dysfunction have been observed in inter-episode bipolar disorder (BD) patients. We aimed to create a joint statistical model of white matter integrity and functional response measures in explaining differences in working memory and processing speed among BD patients. Medicated inter-episode BD (n=26; age=45.2±10.1 years) and healthy comparison (HC; n=36; age=46.3±11.5 years) participants completed 51-direction DTI and fMRI while performing a working memory task. Participants also completed a processing speed test. Tract-based spatial statistics identified common white matter tracts where fractional anisotropy was calculated from atlas-defined regions of interest. Brain responses within regions of interest activation clusters were also calculated. Least angle regression was used to fuse fMRI and DTI data to select the best joint neuroimaging predictors of cognitive performance for each group. While there was overlap between groups in which regions were most related to cognitive performance, some relationships differed between groups. For working memory accuracy, BD-specific predictors included bilateral dorsolateral prefrontal cortex from fMRI, splenium of the corpus callosum, left uncinate fasciculus, and bilateral superior longitudinal fasciculi from DTI. For processing speed, the genu and splenium of the corpus callosum and right superior longitudinal fasciculus from DTI were significant predictors of cognitive performance selectively for BD patients. BD patients demonstrated unique brain-cognition relationships compared to HC. These findings are a first step in discovering how interactions of structural and functional brain abnormalities contribute to cognitive impairments in BD. (JINS, 2015, 21, 330-341). PMID:26037664

  13. Memory Systems Doug Burger

    E-print Network

    Burger, Doug

    Memory Systems Doug Burger University of Wisconsin-Madison A computer's memory system and produces. A perfect memory system is one that can supply immediately any datum that the CPU requests. This ideal memory is not practically implementable, however, as the three factors of memory capacity, speed

  14. Perceptual centers (P-centers)

    Microsoft Academic Search

    John Morton; Steve Marcus; Clive Frankish

    1976-01-01

    Words presented with regular acoustic onsets are not perceptually regular. The requirements for perceived regularity were investigated, and the perceptual center (P-center) of a word was defined as its psychological moment of occurrence. Some properties of these perceptual centers have been empirically determined, and the range of their applicability is sketched. In particular, it is already clear that temporal alignment

  15. Perceptual Aspects of Motor Performance.

    ERIC Educational Resources Information Center

    Gallahue, David L.

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

  16. Acetylcholine and Olfactory Perceptual Learning

    ERIC Educational Resources Information Center

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

    2004-01-01

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

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

    PubMed Central

    Gilchrist, Amanda L.; Cowan, Nelson

    2014-01-01

    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

  18. Neural mechanisms underlying the induction and relief of perceptual curiosity

    PubMed Central

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

    2012-01-01

    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

  19. Perceptual Learning in Speech

    ERIC Educational Resources Information Center

    Norris, Dennis; McQueen, James M.; Cutler, Anne

    2003-01-01

    This study demonstrates that listeners use lexical knowledge in perceptual learning of speech sounds. Dutch listeners first made lexical decisions on Dutch words and nonwords. The final fricative of 20 critical words had been replaced by an ambiguous sound, between [f] and [s]. One group of listeners heard ambiguous [f]-final words (e.g.,…

  20. The Perceptual Domain.

    ERIC Educational Resources Information Center

    Hooker, Ellen Z.

    For purposes of allied health education applicability, the perceptual domain was examined in terms of (1) its own taxonomy and (2) its relationship to taxonomies in the cognitive, affective, and psychomotor domains. All these taxonomies are hierarchical in style; perception involves extraction of information from presenting stimuli and there is…

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

    PubMed

    Sheridan, Heather; Reingold, Eyal M

    2012-12-01

    The present study used eye tracking methodology to examine rereading benefits for spatially transformed text. Eye movements were monitored while participants read the same target word twice, in two different low-constraint sentence frames. The congruency of perceptual processing was manipulated by either applying the same type of transformation to the word during the first and second presentations (i.e., the congruent condition), or employing two different types of transformations across the two presentations of the word (i.e., the incongruent condition). Perceptual specificity effects were demonstrated such that fixation times for the second presentation of the target word were shorter for the congruent condition compared to the incongruent condition. Moreover, we demonstrated an additional perceptually non-specific effect such that second reading fixation times were shorter for the incongruent condition relative to a baseline condition that employed a normal typography (i.e., non-transformed) during the first presentation and a transformation during the second presentation. Both of these effects (i.e., perceptually specific and perceptually non-specific) were similar in magnitude for high and low frequency words, and both effects persisted across a 1 week lag between the first and second readings. We discuss the present findings in the context of the distinction between conscious and unconscious memory, and the distinction between perceptually versus conceptually driven processing. PMID:23138157

  2. The effects of selective attention on perceptual priming and explicit recognition in children with attention deficit and normal children

    Microsoft Academic Search

    Soledad Ballesteros; José M. Reales; Beatriz García

    2007-01-01

    Perceptual priming and recognition for attended and unattended pictures at encoding, compared to nonstudied pictures were examined in second and fifth grade schoolchildren with attention deficit (AD) and children without AD. In the study, a visual perceptual priming paradigm was combined with a selective attention procedure at encoding to look for the influence of attention in implicit and explicit memory

  3. Auditory Perceptual Category Formation Does Not Require Perceptual Warping.

    PubMed

    Caruso, Valeria C; Balaban, Evan

    2015-08-01

    Categorical perception occurs when a perceiver's stimulus classifications affect their ability to make fine perceptual discriminations and is the most intensively studied form of category learning. On the basis of categorical perception studies, it has been proposed that category learning proceeds by the deformation of an initially homogeneous perceptual space ("perceptual warping"), so that stimuli within the same category are perceived as more similar to each other (more difficult to tell apart) than stimuli that are the same physical distance apart but that belong to different categories. Here, we present a significant counterexample in which robust category learning occurs without these differential perceptual space deformations. Two artificial categories were defined along the dimension of pitch for a perceptually unfamiliar, multidimensional class of sounds. A group of participants (selected on the basis of their listening abilities) were trained to sort sounds into these two arbitrary categories. Category formation, verified empirically, was accompanied by a heightened sensitivity along the entire pitch range, as indicated by changes in an EEG index of implicit perceptual distance (mismatch negativity), with no significant resemblance to the local perceptual deformations predicted by categorical perception. This demonstrates that robust categories can be initially formed within a continuous perceptual dimension without perceptual warping. We suggest that perceptual category formation is a flexible, multistage process sequentially combining different types of learning mechanisms rather than a single process with a universal set of behavioral and neural correlates. PMID:25803599

  4. Computer-Based Cognitive Programs for Improvement of Memory, Processing Speed and Executive Function during Age-Related Cognitive Decline: A Meta-Analysis

    PubMed Central

    Shao, Yan-kun; Mang, Jing; Li, Pei-lan; Wang, Jie; Deng, Ting; Xu, Zhong-xin

    2015-01-01

    Background Several studies have assessed the effects of computer-based cognitive programs (CCP) in the management of age-related cognitive decline, but the role of CCP remains controversial. Therefore, this systematic review evaluated the evidence on the efficacy of CCP for age-related cognitive decline in healthy older adults. Methods Six electronic databases (through October 2014) were searched. The risk of bias was assessed using the Cochrane Collaboration tool. The standardized mean difference (SMD) and 95% confidence intervals (CI) of a random-effects model were calculated. The heterogeneity was assessed using the Cochran Q statistic and quantified with the I2 index. Results Twelve studies were included in the current review and were considered as moderate to high methodological quality. The aggregated results indicate that CCP improves memory performance (SMD, 0.31; 95% CI 0.16 to 0.45; p < 0.0001) and processing speed (SMD, 0.50; 95% CI 0.14 to 0.87; p = 0.007) but not executive function (SMD, -0.12; 95% CI -0.33 to 0.09; p = 0.27). Furthermore, there were long-term gains in memory performance (SMD, 0.59; 95% CI 0.13 to 1.05; p = 0.01). Conclusion CCP may be a valid complementary and alternative therapy for age-related cognitive decline, especially for memory performance and processing speed. However, more studies with longer follow-ups are warranted to confirm the current findings. PMID:26098943

  5. Why drivers speed: The speeding perception inventory

    Microsoft Academic Search

    Steve G. Gabany; Portia Plummer; Pat Grigg

    1997-01-01

    This study reports initial results of a project to better understand the factors that predispose, enable, and reinforce drivers' speeding behavior. This information is essential for successful traffic safety programs. A perceptual inventory was developed and administered to a large, college-age sample. High levels of internal consistency were found. Factor analysis suggested five predisposing, enabling, and reinforcing constructs: 1.(a) Ego-gratification;2.(b)

  6. Are Cochlear Implant Patients Suffering From Perceptual Dissonance?

    E-print Network

    Loeb, Gerald E.

    Are Cochlear Implant Patients Suffering From Perceptual Dissonance? Gerald E. Loeb, M.D. Cochlear suggests that the place-pitch and rate-pitch theories on which cochlear implants have been designed-speed, and high-density cochlear implants may make it possi- ble to identify more efficiently the best strategy

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

  8. Neuroanatomic Organization of Sound Memory in Humans

    Microsoft Academic Search

    Michael A. Kraut; Jeffery A. Pitcock; Vince Calhoun; Juan Li; Thomas Freeman

    2006-01-01

    The neural interface between sensory perception and memory is a central issue in neuroscience, particularly initial memory organization following perceptual analyses. We used functional magnetic resonance imaging to identify anatomic regions extracting initial auditory semantic memory information related to environmental sounds. Two distinct anatomic foci were detected in the right superior temporal gyrus when subjects identified sounds representing either animals

  9. Abstraction in perceptual symbol systems.

    PubMed Central

    Barsalou, Lawrence W

    2003-01-01

    After reviewing six senses of abstraction, this article focuses on abstractions that take the form of summary representations. Three central properties of these abstractions are established: ( i ) type-token interpretation; (ii) structured representation; and (iii) dynamic realization. Traditional theories of representation handle interpretation and structure well but are not sufficiently dynamical. Conversely, connectionist theories are exquisitely dynamic but have problems with structure. Perceptual symbol systems offer an approach that implements all three properties naturally. Within this framework, a loose collection of property and relation simulators develops to represent abstractions. Type-token interpretation results from binding a property simulator to a region of a perceived or simulated category member. Structured representation results from binding a configuration of property and relation simulators to multiple regions in an integrated manner. Dynamic realization results from applying different subsets of property and relation simulators to category members on different occasions. From this standpoint, there are no permanent or complete abstractions of a category in memory. Instead, abstraction is the skill to construct temporary online interpretations of a category's members. Although an infinite number of abstractions are possible, attractors develop for habitual approaches to interpretation. This approach provides new ways of thinking about abstraction phenomena in categorization, inference, background knowledge and learning. PMID:12903648

  10. How Minds Work Memories and Learning

    E-print Network

    Memphis, University of

    in ­ Primitive feature detectors ­ Preferences for learnings ­ Attention mechanism ­ Base level activation & Learning 9 A mechanism for perceptual learning · Semantic net with activation passing · Nodes · Learning modifies baselevel activation #12;How Minds Work: Memory & Learning 10 A mechanism for episodic

  11. The measurement of perceptual curiosity

    Microsoft Academic Search

    Robert P Collins; Jordan A Litman; Charles D Spielberger

    2004-01-01

    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

  12. Unconscious orientation processing depends on perceptual load

    E-print Network

    Lavie, Nilli

    Unconscious orientation processing depends on perceptual load Institute of Cognitive Neuroscience, London, UKNilli Lavie The effects of perceptual load on the level of adaptation to task (detecting color targets) or high (detecting conjunctions of color and shape) perceptual load. Simultaneously

  13. Measures of Learning, Memory and Processing Speed Accurately Predict Smoking Status in Short-term Abstinent Treatment-seeking Alcohol-dependent Individuals

    PubMed Central

    Durazzo, Timothy C.; Fryer, Susanna L.; Rothlind, Johannes C.; Vertinski, Mary; Gazdzinski, Stefan; Mon, Anderson; Meyerhoff, Dieter J.

    2010-01-01

    Aim: Chronic cigarette smoking appears to adversely affect several domains of neurocognition in those with alcohol use disorders (AUDs). The primary goal of this study was to identify which measures commonly used to assess neurocognition in AUDs accurately predict smoking status of individuals seeking treatment of alcohol dependence. Methods: Treatment-seeking alcohol-dependent participants (ALC; n = 92) completed a comprehensive neuropsychological battery after 33 ± 9 days of abstinence. Measures significantly different between smoking and non-smoking ALC were entered as predictors in binary logistic regression and discriminant analysis models, with smoking status as the dependent variable. Results: Smoking ALC performed significantly worse than non-smoking ALC on measures assessing processing speed, auditory–verbal and visuospatial learning and memory. Using these measures as predictors, a logistic regression model accurately classified 91% of smokers and non-smokers into their respective groups overall and accounted for 68% of the variance in smoking status. The discriminant analysis confirmed the findings from the logistic regression. In smoking ALC, smoking chronicity was inversely related to performance on multiple measures after controlling for lifetime alcohol consumption. Conclusions: Measures of processing speed, learning and memory robustly predicted the smoking status of ALC with high sensitivity and specificity during early abstinence. The results identified specific measures within a comprehensive neurocognitive battery that discriminated smoking and non-smoking alcohol-dependent individuals with a high sensitivity and specificity. The association of greater smoking chronicity and poorer performance on multiple measures after control for alcohol consumption suggests that chronic smoking adds an additional burden to neurocognitive function in those with alcohol dependence. PMID:20923865

  14. Depression, implicit memory, and self: A revised memory model of emotion

    Microsoft Academic Search

    Elaine S. Barry; Mary J. Naus; Lynn P. Rehm

    2006-01-01

    Cognitive constructs are explored for clinical psychologists interested in cognitive phenomena in depression. Both traditional and modern memory constructs are outlined and described with attention to their contribution to understanding depression. In particular, the notions of memory construction, self-schemas, and autobiographical memory (per [Conway, M.A. (2001). Sensory–perceptual episodic memory and its context: Autobiographical memory. Philosophical Transactions of the Royal Society

  15. Perceptual Load Alters Visual Excitability

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  16. Perceptual basis for reactive teleoperation.

    SciTech Connect

    Park, Y. S.; Ewing, T. F.; Boyle, J. M.; Yule, T. J.

    2001-08-28

    To enhance task performance in partially structured environment, enhancement of teleoperation was proposed by introducing autonomous behaviors. Such autonomy is implemented based on reactive robotic architecture, where reactive motor agents that directly couples sensory inputs and motor actions become the building blocks. To this end, presented in this paper is a perceptual basis for the motor agents. The perceptual basis consists of perceptual agents that extracts environmental information from a structured light vision system and provide action oriented perception for the corresponding motor agents. Rather than performing general scene reconstruction, a perceptual agent directly provides the motion reference for the motor behavior. Various sensory mechanisms--sensor fission, fusion, and fashion--becomes basic building blocks of the perception process. Since perception is a process deeply intertwined with the motor actions, active perception may also incorporate motor behaviors as an integral perceptual process.

  17. Perceptual Load Modulates Object-Based Attention

    ERIC Educational Resources Information Center

    Ho, Ming-Chou; Atchley, Paul

    2009-01-01

    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…

  18. Modes of memory: Early electrophysiological markers of repetition suppression and recognition enhancement

    E-print Network

    Wagner, Anthony

    Modes of memory: Early electrophysiological markers of repetition suppression and recognition,b and CHRISTOPH S. HERRMANNa a Institute of Psychology, Department of Biological Psychology, Otto, Saarbru¨ cken, Germany Abstract Different forms of perceptual memory have opposite physiological effects

  19. Dual-task interference in perceptual category learning.

    PubMed

    Zeithamova, Dagmar; Maddox, W Todd

    2006-03-01

    The effect of a working-memory-demanding dual task on perceptual category learning was investigated. In Experiment 1, participants learned unidimensional rule-based or information integration category structures. In Experiment 2, participants learned a conjunctive rule-based category structure. In Experiment 1, unidimensional rule-based category learning was disrupted more by the dual working memory task than was information integration category learning. In addition, rule-based category learning differed qualitatively from information integration category learning in yielding a bimodal, rather than a normal, distribution of scores. Experiment 2 showed that rule-based learning can be disrupted by a dual working memory task even when both dimensions are relevant for optimal categorization. The results support the notion of at least two systems of category learning a hypothesis-testing system that seeks verbalizable rules and relies on working memory and selective attention, and an implicit system that is procedural-learning based and is essentially automatic. PMID:16752602

  20. Perceptual style and tracking performance

    NASA Technical Reports Server (NTRS)

    Atchley, Paul

    1991-01-01

    The relationship between perceptual style and tracking of a target was examined. Four pilots were given the Embedded Figures Test to assess their degrees of field dependence or independence. Then they flew in a helicopter simulator and attempted to track an airborne target. A high negative correlation was found between perceptual style and tracking performance. Field-independent subjects were able to track the target for longer periods than field-dependent subjects.

  1. Perceptual anomalies in schizophrenia: integrating phenomenology and cognitive neuroscience.

    PubMed

    Uhlhaas, Peter J; Mishara, Aaron L

    2007-01-01

    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

  2. The time required for perceptual (nonmotoric) processing in IOR

    Microsoft Academic Search

    Thomas M. Spalek; Vincent Di Lollo

    2007-01-01

    In an inhibition of return (IOR) paradigm, we used a threshold-tracking procedure combined with backward masking to measure\\u000a the speed of perceptual processing in IOR independent of motoric factors. Instead of the conventional reaction time measure,\\u000a this procedure yielded the critical exposure duration (DURc) that is required in order for a target to be identified reliably before the onset of

  3. The perceptual threshold for overweight.

    PubMed

    Johnson, William G; Stewart, Regan; Pusser, Andrea T

    2012-08-01

    Normative, global overweight may play a prominent role in perpetuating the obesity epidemic via its contribution to weight-related norms that describe what is customary in a social environment. These weight-related norms include a perceptual standard determining where body weight shifts from normal to overweight. We introduce the construct of a perceptual threshold for overweight to identify this transition point. The perceptual threshold is measured on 0-100mm scales positioned below adult and child figures. This report presents three studies that evaluate the psychometric properties of this variable. Study 1explored its independence from BMI and body image in factor analyses with diverse samples (Ukrainian, Mexican and US Black, White, and Hispanic). Study 2 was a replication of this factor structure, and Study 3 investigated the reliability of the perceptual threshold using classical test (CT) and generalizability methods (GT). In Studies 1 and 2, two factors were identified (Perceptual Threshold for Overweight and Body Image/BMI) with almost identical factor structures in six analyses. In Study 3 the CT and GT procedures demonstrated adequate reliability. These results indicate that the psychometric properties of the perceptual threshold are sound, and support its use in exploring the social transmission of weight and evaluating obesity prevention and intervention programs. PMID:22664395

  4. Dimensional Implicit Memory Priming Deficits in Young ADHD Adults 

    E-print Network

    Tatman, Christopher G

    2012-07-11

    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...

  5. Multisensory Integration Effect on Feature Binding in Visual Working Memory 

    E-print Network

    Kanellopoulos, Athanasios

    2013-08-13

    The focus of this experiment is to assess the effect of spatial attention biases on access to information in perceptual and visual working memory by cuing trials using auditory, visual or audiovisual signals in change ...

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

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  7. A Developmental Examination of Basic Perceptual Processes in Reading. Final Report.

    ERIC Educational Resources Information Center

    Lefton, Lester A.

    This report summarizes four groups of experiments examining the nature of basic perceptual processes in reading. The first group examined the relationship of English orthography to reading, specifically the transfer of information from the icon to short-term memory. The second group of experiments examined the use of peripheral information…

  8. Subcortical hyperintensity volumetrics in Alzheimer’s disease and normal elderly in the Sunnybrook Dementia Study: correlations with atrophy, executive function, mental processing speed, and verbal memory

    PubMed Central

    2014-01-01

    Introduction Subcortical hyperintensities (SHs) are radiological entities commonly observed on magnetic resonance imaging (MRI) of patients with Alzheimer’s disease (AD) and normal elderly controls. Although the presence of SH is believed to indicate some form of subcortical vasculopathy, pathological heterogeneity, methodological differences, and the contribution of brain atrophy associated with AD pathology have yielded inconsistent results in the literature. Methods Using the Lesion Explorer (LE) MRI processing pipeline for SH quantification and brain atrophy, this study examined SH volumes of interest and cognitive function in a sample of patients with AD (n?=?265) and normal elderly controls (n?=?100) from the Sunnybrook Dementia Study. Results Compared with healthy controls, patients with AD were found to have less gray matter, less white matter, and more sulcal and ventricular cerebrospinal fluid (all significant, P <0.0001). Additionally, patients with AD had greater volumes of whole-brain SH (P <0.01), periventricular SH (pvSH) (P <0.01), deep white SH (dwSH) (P <0.05), and lacunar lesions (P <0.0001). In patients with AD, regression analyses revealed a significant association between global atrophy and pvSH (P?=?0.02) and ventricular atrophy with whole-brain SH (P <0.0001). Regional volumes of interest revealed significant correlations with medial middle frontal SH volume and executive function (P <0.001) in normal controls but not in patients with AD, global pvSH volume and mental processing speed (P <0.01) in patients with AD, and left temporal SH volume and memory (P <0.01) in patients with AD. Conclusions These brain-behavior relationships and correlations with brain atrophy suggest that subtle, yet measurable, signs of small vessel disease may have potential clinical relevance as targets for treatment in Alzheimer’s dementia. PMID:25478020

  9. Increased Signal Complexity Improves the Breadth of Generalization in Auditory Perceptual Learning

    PubMed Central

    Brown, David J.; Proulx, Michael J.

    2013-01-01

    Perceptual learning can be specific to a trained stimulus or optimally generalized to novel stimuli with the breadth of generalization being imperative for how we structure perceptual training programs. Adapting an established auditory interval discrimination paradigm to utilise complex signals, we trained human adults on a standard interval for either 2, 4, or 10 days. We then tested the standard, alternate frequency, interval, and stereo input conditions to evaluate the rapidity of specific learning and breadth of generalization over the time course. In comparison with previous research using simple stimuli, the speed of perceptual learning and breadth of generalization were more rapid and greater in magnitude, including novel generalization to an alternate temporal interval within stimulus type. We also investigated the long term maintenance of learning and found that specific and generalized learning was maintained over 3 and 6 months. We discuss these findings regarding stimulus complexity in perceptual learning and how they can inform the development of effective training protocols. PMID:24349800

  10. Neural events and perceptual awareness Nancy Kanwisher*

    E-print Network

    Kanwisher, Nancy

    Neural events and perceptual awareness Nancy Kanwisher* Department of Brain and Cognitive Sciences correlates of perceptual awareness, until very recently an elusive quarry, are now almost commonplace ®ndings. This article ®rst describes a variety of neural correlates of perceptual awareness based on fMRI, ERPs

  11. Perceptual independence: Definitions, models, and experimental paradigms

    Microsoft Academic Search

    W. R. Garner; John Morton

    1969-01-01

    Necessary distinctions in an analysis of the study of perceptual independence are: (1) between the definition of independence as zero correlation and its definition as performance parity, (2) between normative models of perceptual process and models of perceptual state, and (3) between experimental designs which use orthogonal stimulus inputs and those which use correlated inputs. Implications of this analysis are:

  12. Control device for vehicle speed

    SciTech Connect

    Kawata, S.; Hyodo, H.

    1987-03-03

    This patent describes a control device for vehicle speed comprising: a throttle driving means operatively coupled to a throttle valve of a vehicle; a set switch means for commanding memorization of the vehicle speed; a resume switch means for commanding read of the vehicle speed; a vehicle speed detecting means for generating a signal in accordance with the vehicle speed; a vehicle speed memory; an electronical control means for memorizing in the vehicle speed memory vehicle speed information corresponding to the signal obtained from the vehicle speed detecting means in response to actuation of the set switch means. The control means is also for reading out the content of the vehicle speed memory in response to actuation of the resume switch means to control the throttle driving means in accordance with the read-out content; a power supply means for supplying power to the electronical control means; and a power supply control switch means for controlling supply of power to the electronical control means in response to the state of at least one of the set switch means and the resume switch means and the state of the electronical control means. The improvement described here comprises the electronical control means sets the power supply control switch means into such a state that supply of power to the electronical control means is turned OFF, when vehicle speed information is not memorized in the vehicle speed memory.

  13. Perceptual and conceptual priming in patients with dissociative identity disorder.

    PubMed

    Huntjens, Rafaële J C; Postma, Albert; Hamaker, Ellen L; Woertman, Liesbeth; van der Hart, Onno; Peters, Madelon

    2002-10-01

    The present study examined implicit memory transfer in patients with dissociative identity disorder (DID). To determine priming impairments in DID, we included both several perceptual priming tasks and a conceptual priming task using neutral material. We tested a large sample of DID patients (n = 31), in addition to 25 controls and 25 DID simulators, comparable on sex, age, and education. Controls replicated conceptual priming results of Vriezen, Moscovitch, and Bellos (1995) by showing that conceptual priming seems to require the formation of domain-specific semantic representations, denoting either sensory or functional object attributes. We extended a study performed by Schacter, Cooper, and Delaney (1990) by demonstrating priming for impossible object using the sensitive priming index of response times. The simulators in the study were not able to simulate interidentity amnesia on the implicit memory tasks employed. Partly in contrast to participants in previous studies, DID patients showed evidence of perceptual priming as well as conceptual priming comparable to that of controls. DID patients thus displayed normal implicit memory performance. PMID:12507368

  14. Perceptual hysteresis as a marker of perceptual inflexibility in schizophrenia.

    PubMed

    Martin, Jean-Rémy; Dezecache, Guillaume; Pressnitzer, Daniel; Nuss, Philippe; Dokic, Jérôme; Bruno, Nicolas; Pacherie, Elisabeth; Franck, Nicolas

    2014-11-01

    People with schizophrenia are known to exhibit difficulties in the updating of their current belief states even in the light of disconfirmatory evidence. In the present study we tested the hypothesis that people with schizophrenia could also manifest perceptual inflexibility, or difficulties in the updating of their current sensory states. The presence of perceptual inflexibility might contribute both to the patients' altered perception of reality and the formation of some delusions as well as to their social cognition deficits. Here, we addressed this issue with a protocol of auditory hysteresis, a direct measure of sensory persistence, on a population of stabilized antipsychotic-treated schizophrenia patients and a sample of control subjects. Trials consisted of emotional signals (i.e., screams) and neutral signals (i.e., spectrally-rotated versions of the emotional stimuli) progressively emerging from white noise - Ascending Sequences - or progressively fading away in white noise - Descending Sequences. Results showed that patients presented significantly stronger hysteresis effects than control subjects, as evidenced by a higher rate of perceptual reports in Descending Sequences. The present study thus provides direct evidence of perceptual inflexibility in schizophrenia. PMID:25147080

  15. Performance and physiological responses of type A and type B individuals during a cognitive and perceptual-motor task.

    PubMed

    Juszczak, N M; Andreassi, J L

    1987-07-01

    A total of 36 male individuals, 18 classified as Type A and 18 as Type B performed a cognitive (tonal memory) and a perceptual-motor (simulated race car driving) task along with a secondary reaction time (RT) task. Heart rate (HR), skin temperature, and skin conductance (SC) were measured. Multiple linear regression analysis revealed that tracking was related to Jenkins Activity Survey indicating superior performance for those scoring high in overall Type A behavior and low in the H sub-scale (hard driving, competitive behavior). Persons scoring high in the S scale (speed and impatience) and low in the H scale performed better in the short-term memory task. Type A subjects had higher HR and performed better (faster RTs and higher scores) than Type Bs, but only while engaged in the cognitive task. The Type As also had higher SCs than Bs, although they were not differentiated according to task. Sub-scale patterns may have important implications for refining the Type A behavior concept. PMID:3610732

  16. Iconic memory requires attention.

    PubMed

    Persuh, Marjan; Genzer, Boris; Melara, Robert D

    2012-01-01

    Two experiments investigated whether attention plays a role in iconic memory, employing either a change detection paradigm (Experiment 1) or a partial-report paradigm (Experiment 2). In each experiment, attention was taxed during initial display presentation, focusing the manipulation on consolidation of information into iconic memory, prior to transfer into working memory. Observers were able to maintain high levels of performance (accuracy of change detection or categorization) even when concurrently performing an easy visual search task (low load). However, when the concurrent search was made difficult (high load), observers' performance dropped to almost chance levels, while search accuracy held at single-task levels. The effects of attentional load remained the same across paradigms. The results suggest that, without attention, participants consolidate in iconic memory only gross representations of the visual scene, information too impoverished for successful detection of perceptual change or categorization of features. PMID:22586389

  17. Improving pulse oximetry pitch perception with multisensory perceptual training.

    PubMed

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

    2014-06-01

    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

  18. The role of attentional breadth in perceptual change detection.

    PubMed

    Pringle, H L; Irwin, D E; Kramer, A F; Atchley, P

    2001-03-01

    Previous research has shown that changes to scenes are often surprisingly hard to detect. The research reported here investigated the relationship between individual differences in attention and change detection. We did this by assessing participants' breadth of attention in a functional field of view task (FFOV) and relating this measure to the speed with which individuals detected changes in scenes. We also examined how the salience, meaningfulness, and eccentricity of the scene changes affected perceptual change performance. In order to broaden the range of individual differences in attentional breadth, both young and old adults participated in the study. A strong negative relationship was obtained between attentional breadth and the latency with which perceptual changes were detected; observers with broader attentional windows detected changes faster. Salience and eccentricity had large effects on change detection, but meaning aided the performance of young adults only and only when changes also had low salience. PMID:11340871

  19. The time required for perceptual (nonmotoric) processing in IOR.

    PubMed

    Spalek, Thomas M; Di Lollo, Vincent

    2007-04-01

    In an inhibition of return (IOR) paradigm, we used a threshold-tracking procedure combined with backward masking to measure the speed of perceptual processing in IOR independent of motoric factors. Instead of the conventional reaction time measure, this procedure yielded the critical exposure duration (DURc) that is required in order for a target to be identified reliably before the onset of a trailing mask. In Experiment 1, the facilitation effects conventionally found at short cue-target onset asynchrony (CTOA) were evidenced by shorter values of DURc at cued relative to uncued locations. Conversely, the retardation effects conventionally found at long CTOA were evidenced by correspondingly longer values of DURc. In Experiment 2, the DURc results strongly suggest that the directional reading bias previously observed in IOR studies is due, at least in part, to perceptual rather than motoric factors. PMID:17694921

  20. Some Perceptual Prerequisites for Reading.

    ERIC Educational Resources Information Center

    Frith, Uta; Vogel, Juliet M.

    The two chapters of this monograph deal with the issue of the existence of a perceptual grammar that influences reading proficiency, particularly initial reading proficiency. The first chapter indicates the importance of studying reading and writing in terms of readers' and writers' knowledge of visuo-spatial processing rules. It discusses…

  1. Perceptual Aspects of Cluttered Speech

    ERIC Educational Resources Information Center

    St. Louis, Kenneth O.; Myers, Florence L.; Faragasso, Kristine; Townsend, Paula S.; Gallaher, Amanda J.

    2004-01-01

    The purpose of this descriptive investigation was to explore perceptual judgments of speech naturalness, compared to judgments of articulation, language, disfluency, and speaking rate, in the speech of two youths who differed in cluttering severity. Two groups of listeners, 48 from New York and 48 from West Virginia, judged 93 speaking samples on…

  2. Perceptually guided expressive facial animation

    Microsoft Academic Search

    Zhigang Deng; Xiaohan Ma

    2008-01-01

    Most of current facial animation approaches largely focus on the accuracy or efficiency of their algorithms, or how to optimally utilize pre-collected facial motion data. However, human perception, the ultimate measuring stick of the visual fidelity of synthetic facial animations, was not effectively exploited in these approaches. In this paper, we present a novel perceptually guided computational framework for expressive

  3. Odor identification: perceptual and semantic dimensions.

    PubMed

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

    1998-06-01

    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

  4. Perceptual and Linguistic Processing of Letters and Words By Normal and Disabled Readers

    ERIC Educational Resources Information Center

    Steinheiser, Rick; Guthrie, John T.

    1977-01-01

    Response latencies were obtained in word matching and sentence completion tasks from disabled readers, age-matched normal readers, and reading-level matched normal readers. Results indicated that perceptual and semantic processing are interconnected and improvements in the speed and accuracy of one facilitates improvements in the other. (HOD)

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

    PubMed

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

    2014-01-01

    It is well established that auditory cueing improves gait in patients with idiopathic Parkinson's disease (IPD). Disease-related reductions in speed and step length can be improved by providing rhythmical auditory cues via a metronome or music. However, effects on cognitive aspects of motor control have yet to be thoroughly investigated. If synchronization of movement to an auditory cue relies on a supramodal timing system involved in perceptual, motor, and sensorimotor integration, auditory cueing can be expected to affect both motor and perceptual timing. Here, we tested this hypothesis by assessing perceptual and motor timing in 15 IPD patients before and after a 4-week music training program with rhythmic auditory cueing. Long-term effects were assessed 1?month after the end of the training. Perceptual and motor timing was evaluated with a battery for the assessment of auditory sensorimotor and timing abilities and compared to that of age-, gender-, and education-matched healthy controls. Prior to training, IPD patients exhibited impaired perceptual and motor timing. Training improved patients' performance in tasks requiring synchronization with isochronous sequences, and enhanced their ability to adapt to durational changes in a sequence in hand tapping tasks. Benefits of cueing extended to time perception (duration discrimination and detection of misaligned beats in musical excerpts). The current results demonstrate that auditory cueing leads to benefits beyond gait and support the idea that coupling gait to rhythmic auditory cues in IPD patients relies on a neuronal network engaged in both perceptual and motor timing. PMID:25071522

  6. Visual Working Memory Contents Bias Ambiguous Structure from Motion Perception

    PubMed Central

    Scocchia, Lisa; Valsecchi, Matteo; Gegenfurtner, Karl R.; Triesch, Jochen

    2013-01-01

    The way we perceive the visual world depends crucially on the state of the observer. In the present study we show that what we are holding in working memory (WM) can bias the way we perceive ambiguous structure from motion stimuli. Holding in memory the percept of an unambiguously rotating sphere influenced the perceived direction of motion of an ambiguously rotating sphere presented shortly thereafter. In particular, we found a systematic difference between congruent dominance periods where the perceived direction of the ambiguous stimulus corresponded to the direction of the unambiguous one and incongruent dominance periods. Congruent dominance periods were more frequent when participants memorized the speed of the unambiguous sphere for delayed discrimination than when they performed an immediate judgment on a change in its speed. The analysis of dominance time-course showed that a sustained tendency to perceive the same direction of motion as the prior stimulus emerged only in the WM condition, whereas in the attention condition perceptual dominance dropped to chance levels at the end of the trial. The results are explained in terms of a direct involvement of early visual areas in the active representation of visual motion in WM. PMID:23527141

  7. Cognitive Style and Reasoning about Speed

    ERIC Educational Resources Information Center

    Ehri, Linnea C.; Muzio, Irene M.

    1974-01-01

    College students were asked to reason about the relative speeds of horses turning on a merry-go-round platform. Results revealed that, unlike field independent subjects, field dependent subjects failed to reason analytically. They were misled by perceptually salient aspects of the situation. They resisted accomodating to additional information.…

  8. Exploiting perceptual redundancy in images

    NASA Astrophysics Data System (ADS)

    Liu, Hongyi; Chen, Zhenzhong

    2015-03-01

    Exploiting perceptual redundancy plays an important role in image processing. Conventional JND models describe the visibility of the minimally perceptible difference by assuming that the visual acuity is consistent over the whole image. Some earlier work considers the space-variant properties of HVS-based on the non-uniform density of photoreceptor cells. In this paper, we aim to exploit the relationship between the masking effects and the foveation properties of HVS. We design the psychophysical experiments which are conducted to model the foveation properties in response to the masking effects. The experiment examines the reduction of visual sensitivity in HVS due to the increased retinal eccentricity. Based on these experiments, the developed Foveated JND model measures the perceptible difference of images according to masking effects therefore provides the information to quantify the perceptual redundancy in the images. Subjective evaluations validate the proposed FJND model.

  9. Minimalist Approach to Perceptual Interactions

    PubMed Central

    Lenay, Charles; Stewart, John

    2012-01-01

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

  10. Adaptive and perceptual learning technologies in medical education and training.

    PubMed

    Kellman, Philip J

    2013-10-01

    Recent advances in the learning sciences offer remarkable potential to improve medical education and maximize the benefits of emerging medical technologies. This article describes 2 major innovation areas in the learning sciences that apply to simulation and other aspects of medical learning: Perceptual learning (PL) and adaptive learning technologies. PL technology offers, for the first time, systematic, computer-based methods for teaching pattern recognition, structural intuition, transfer, and fluency. Synergistic with PL are new adaptive learning technologies that optimize learning for each individual, embed objective assessment, and implement mastery criteria. The author describes the Adaptive Response-Time-based Sequencing (ARTS) system, which uses each learner's accuracy and speed in interactive learning to guide spacing, sequencing, and mastery. In recent efforts, these new technologies have been applied in medical learning contexts, including adaptive learning modules for initial medical diagnosis and perceptual/adaptive learning modules (PALMs) in dermatology, histology, and radiology. Results of all these efforts indicate the remarkable potential of perceptual and adaptive learning technologies, individually and in combination, to improve learning in a variety of medical domains. PMID:24084310

  11. The effect of perceptual grouping on haptic numerosity perception.

    PubMed

    Verlaers, K; Wagemans, J; Overvliet, K E

    2015-01-01

    We used a haptic enumeration task to investigate whether enumeration can be facilitated by perceptual grouping in the haptic modality. Eight participants were asked to count tangible dots as quickly and accurately as possible, while moving their finger pad over a tactile display. In Experiment 1, we manipulated the number and organization of the dots, while keeping the total exploration area constant. The dots were either evenly distributed on a horizontal line (baseline condition) or organized into groups based on either proximity (dots placed in closer proximity to each other) or configural cues (dots placed in a geometric configuration). In Experiment 2, we varied the distance between the subsets of dots. We hypothesized that when subsets of dots can be grouped together, the enumeration time will be shorter and accuracy will be higher than in the baseline condition. The results of both experiments showed faster enumeration for the configural condition than for the baseline condition, indicating that configural grouping also facilitates haptic enumeration. In Experiment 2, faster enumeration was also observed for the proximity condition than for the baseline condition. Thus, perceptual grouping speeds up haptic enumeration by both configural and proximity cues, suggesting that similar mechanisms underlie perceptual grouping in both visual and haptic enumeration. PMID:25248621

  12. A spherical perceptual color model

    NASA Astrophysics Data System (ADS)

    Chen, Tieling; Deng, Zhongmin; Ma, Jun

    2013-02-01

    The paper introduces a transformed spherical model to represent the color space. A circular cone with a spherical top tightly circumscribing the RGB color cube is equipped with a spherical coordinate system. Every point in the color cube is represented by three spherical coordinates, with the radius ? measuring the distance to the origin, indicating the brightness attribute of the color, the azimuthal angle ? measuring the angle on the horizontal plane, indicating the hue attribute of the color, and the polar angle ? measuring the opening of the circular cone with the vertical axis as its center, indicating the saturation attribute of the color. Similar to the commonly used perceptual color models including the HSV model, the spherical model specifies color by describing the color attributes recognized by human vision. The conversions between the spherical model and the RGB color model are mathematically simpler than that of the HSV model, and the interpretation of the model is more intuitive too. Most importantly, color changes perceptually smoother in the spherical color model than in the existing perceptual color models.

  13. Embodied Memory Judgments: A Case of Motor Fluency

    ERIC Educational Resources Information Center

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

    2009-01-01

    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,…

  14. Modeling Age-Related Differences in Immediate Memory Using SIMPLE

    ERIC Educational Resources Information Center

    Surprenant, Aimee M.; Neath, Ian; Brown, Gordon D. A.

    2006-01-01

    In the SIMPLE model (Scale Invariant Memory and Perceptual Learning), performance on memory tasks is determined by the locations of items in multidimensional space, and better performance is associated with having fewer close neighbors. Unlike most previous simulations with SIMPLE, the ones reported here used measured, rather than assumed,…

  15. Coarse-to-Fine Encoding of Spatial Frequency Information Into Visual Short-Term Memory for Faces but Impartial Decay

    PubMed Central

    Gao, Zaifeng; Bentin, Shlomo

    2011-01-01

    Face perception studies investigated how spatial frequencies (SF) are extracted from retinal display while forming a perceptual representation, or their selective use during task-imposed categorization. Here we focused on the order of encoding low-spatial frequencies (LSF) and high-spatial frequencies (HSF) from perceptual representations into visual short-term memory (VSTM). We also investigated whether different SF-ranges decay from VSTM at different rates during a study-test stimulus-onset asynchrony. An old/new VSTM paradigm was used in which two broadband faces formed the positive set and the probes preserved either low or high SF ranges. Exposure time of 500 ms was sufficient to encode both HSF and LSF in the perceptual representation (experiment 1). Nevertheless, when the positive-set was exposed for 500 ms, LSF-probes were better recognized in VSTM compared with HSF-probes; this effect vanished at 800-ms exposure time (experiment 2). Backward masking the positive set exposed for 800 ms re-established the LSF-probes advantage (experiment 3). The speed of decay up to 10 seconds was similar for LSF- and HSF-probes (experiment 4). These results indicate that LSF are extracted and consolidated into VSTM faster than HSF, supporting a coarse-to-fine order, while the decay from VSTM is not governed by SF. PMID:21500938

  16. Neuroanatomical and cognitive mediators of age-related differences in perceptual priming and learning

    PubMed Central

    Kennedy, Kristen M.; Rodrigue, Karen M.; Head, Denise; Gunning-Dixon, Faith; Raz, Naftali

    2009-01-01

    Our objectives were to assess age differences in perceptual repetition priming and perceptual skill learning, and to determine whether they are mediated by cognitive resources and regional cerebral volume differences. Fragmented picture identification paradigm allows the study of both priming and learning within the same task. We presented this task to 169 adults (ages 18–80), assessed working memory and fluid intelligence, and measured brain volumes of regions that were deemed relevant to those cognitive skills. The data were analyzed within a hierarchical path modeling framework. In addition to finding age-related decrease in both perceptual priming and learning, we observed several dissociations with regards to their neural and cognitive mediators. Larger visual cortex volume was associated with greater repetition priming, but not perceptual skill learning, and neither process depended upon hippocampal volume. In contrast, the volumes of the prefrontal gray and white matter were differentially related to both processes via direct and indirect effects of cognitive resources. The results indicate that age-related differences in perceptual priming and skill learning have dissociable cognitive and neural correlates. PMID:19586211

  17. Does perceptual learning require consciousness or attention?

    PubMed

    Meuwese, Julia D I; Post, Ruben A G; Scholte, H Steven; Lamme, Victor A F

    2013-10-01

    It has been proposed that visual attention and consciousness are separate [Koch, C., & Tsuchiya, N. Attention and consciousness: Two distinct brain processes. Trends in Cognitive Sciences, 11, 16-22, 2007] and possibly even orthogonal processes [Lamme, V. A. F. Why visual attention and awareness are different. Trends in Cognitive Sciences, 7, 12-18, 2003]. Attention and consciousness converge when conscious visual percepts are attended and hence become available for conscious report. In such a view, a lack of reportability can have two causes: the absence of attention or the absence of a conscious percept. This raises an important question in the field of perceptual learning. It is known that learning can occur in the absence of reportability [Gutnisky, D. A., Hansen, B. J., Iliescu, B. F., & Dragoi, V. Attention alters visual plasticity during exposure-based learning. Current Biology, 19, 555-560, 2009; Seitz, A. R., Kim, D., & Watanabe, T. Rewards evoke learning of unconsciously processed visual stimuli in adult humans. Neuron, 61, 700-707, 2009; Seitz, A. R., & Watanabe, T. Is subliminal learning really passive? Nature, 422, 36, 2003; Watanabe, T., Náñez, J. E., & Sasaki, Y. Perceptual learning without perception. Nature, 413, 844-848, 2001], but it is unclear which of the two ingredients-consciousness or attention-is not necessary for learning. We presented textured figure-ground stimuli and manipulated reportability either by masking (which only interferes with consciousness) or with an inattention paradigm (which only interferes with attention). During the second session (24 hr later), learning was assessed neurally and behaviorally, via differences in figure-ground ERPs and via a detection task. Behavioral and neural learning effects were found for stimuli presented in the inattention paradigm and not for masked stimuli. Interestingly, the behavioral learning effect only became apparent when performance feedback was given on the task to measure learning, suggesting that the memory trace that is formed during inattention is latent until accessed. The results suggest that learning requires consciousness, and not attention, and further strengthen the idea that consciousness is separate from attention. PMID:23691987

  18. Transient and sustained activity in a distributed neural system for human working memory

    Microsoft Academic Search

    Susan M. Courtney; Leslie G. Ungerleider; Katrina Keil; James V. Haxby

    1997-01-01

    Working memory involves the short-term maintenance of an active representation of information so that it is available for further processing. Visual working memory tasks, in which subjects retain the memory of a stimulus over brief delays, require both the perceptual encoding of the stimulus and the subsequent maintenance of its representation after the stimulus is removed from view. Such tasks

  19. Childhood Anxiety and Memory Functioning: A Comparison of Systemic and Processing Accounts.

    ERIC Educational Resources Information Center

    Daleiden, Eric L.

    1998-01-01

    Examined relationship between anxiety and memory in 160 high- and low-trait-anxious sixth through eighth graders. Found that anxiety predicted memory bias toward negative relative to neutral information during conceptual but not perceptual tasks. Anxiety predicted memory bias toward positive relative to neutral information on procedural tasks and…

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

    ERIC Educational Resources Information Center

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

    2005-01-01

    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…

  1. Effective Cue Utilization Reduces Memory Errors in Older Adults Ayanna K. Thomas and John B. Bulevich

    E-print Network

    Patel, Aniruddh D.

    memory performance but have difficulty accessing and using those cues. Keywords: contextual cues, false to promote similarity between perceptual and contextual cues associated with performed and imagined actions memory. One hypothesis for the episodic memory deficit is that older adults may not encode contextual

  2. Memory for the Conditioned Response: The Effects of Potential Interference Introduced Before and After Original Conditioning

    ERIC Educational Resources Information Center

    Wickens, Delos D.; And Others

    1977-01-01

    Investigates the possibility that memory for the conditioned response (CR) may be subject to the same sorts of interference that have been found to operate in verbal and perceptual-motor memory situations. Considers the implications for developing a general theory of memory. (Editor/RK)

  3. Research on Metal Magnetic Memory Testing Technology in Welding Joint of Structure Train (Railway High-Speed Motor Train Set) Locomotive

    Microsoft Academic Search

    Shengyun Wan; Donglei Lu; Xiaokang Zheng

    2011-01-01

    Metal Magnetic Memory Technology?ƒ MMMT?? can find out the residual stress concentration zone and provide early diagnosis for ferromagnetic structure components. The application of MMMT in welded joints inspection has been investigated and compared with the result of X-ray inspection in this paper. The applicability of MMMT in welded joints NDT is also analyzed. The experimental results show MMMT can

  4. IMPLICIT MEMORY IN YOUNG ADULTS WITH ADHD: DOES IT INCLUDE A CONCEPTUAL PRIMING DEFICIT? 

    E-print Network

    Murphy, Stephanie R

    2009-06-09

    This experiment explored the distinction between two implicit memory test paradigms: identification versus production processes and conceptual versus perceptual processes. These dimensions were crossed to produce four different types of implicit...

  5. Subjective perceptual methods for comparing backpacks

    Microsoft Academic Search

    S. J. LEGG; L. PERKO; P. CAMPBELL

    1997-01-01

    Subjective perceptual methods may provide useful information about small differences in backpack design when physiological and biomechanical comparisons are ineffective. This study used two subjective perceptual methods, category ratio scale (CRS) ratings of perceived discomfort and written questionnaires for comparing two types of leisure backpack. CRS ratings of perceived discomfort for each of 24 body regions after 30 min of

  6. Research report Brain mechanisms underlying perceptual causality

    E-print Network

    Corballis, Paul M.

    Keywords: Causal; Thinking; Spatial; Temporal; Contiguity; fMRI 1. Introduction An understandingResearch report Brain mechanisms underlying perceptual causality Jonathan A. Fugelsanga , Matthew E of perceptual causality. Participants were imaged while viewing alternating blocks of causal events in which

  7. PERCEPTUAL KNOWLEDGE CONSTRUCTION FROM ANNOTATED IMAGE COLLECTIONS

    E-print Network

    Chang, Shih-Fu

    PERCEPTUAL KNOWLEDGE CONSTRUCTION FROM ANNOTATED IMAGE COLLECTIONS Ana B. Benitez and Shih-Fu Chang Dept. of Electrical Engineering, Columbia University, New York, NY 10027 {ana, sfchang} @ ee of annotated images. The proposed methods include automatic techniques for constructing perceptual concepts

  8. Early Perceptual Learning Robert L. Goldstone

    E-print Network

    Goldstone, Robert

    rarely because evolu- tion should have already tuned our perceptual systems to be sensitive to the most important elements of the world in which we live (Olshausen & Field, 1996). Having an adaptive perceptual. The gravitational constant is, here on earth, constant. None- theless, people do face different environments

  9. Perceptual decomposition of virtual haptic surfaces

    Microsoft Academic Search

    Louis B. Rosenberg; Bernard D. Adelstein

    1993-01-01

    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

  10. Research Report High Perceptual Load Makes

    E-print Network

    Lavie, Nilli

    Research Report High Perceptual Load Makes Everybody Equal Eliminating Individual Differences in Distractibility With Load Sophie Forster and Nilli Lavie University College London, London, United Kingdom ABSTRACT--Perceptual load has been found to be a pow- erful determinant of distractibility in laboratory

  11. Perceptual load modulates conscious flicker perception

    E-print Network

    Lavie, Nilli

    Perceptual load modulates conscious flicker perception Institute of Cognitive Neuroscience on its own (low perceptual load) or among other letters (high load). Physically identical flickering stimuli were more likely to be perceived as "fused" under high (compared to low) load in the peripheral

  12. Task Specific Devices and the Perceptual Bottleneck*

    E-print Network

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

  13. Perceptually Motivated Approaches to Music Restoration

    Microsoft Academic Search

    Patrick J. Wolfe; Simon J. Godsill

    2001-01-01

    Spurred by the success of perceptual models in audio coding applications, researchers have recently begun to address audio signal enhancement in a similar manner. Here we consider the case of musical recordings degraded by additive broadband noise such as tape hiss, in which the prevention of signal distortion is tantamount to noise removal. We review perceptually motivated approaches to music

  14. Knowledge Representation and Reasoning for Perceptual Anchoring

    Microsoft Academic Search

    Jonas Melchert; Silvia Coradeschi; Amy Loutfi

    2007-01-01

    In this work we report results on the use of symbolic knowledge representation and reasoning (KRR) for perceptual anchoring. Anchoring is the creation and maintenance of a connection between the symbolic and perceptual description that refer to the same physical object in the environment. We extend the anchoring framework to manage the symbolic information in a KRR system, and to

  15. Neural mechanisms of speed perception: transparent motion

    PubMed Central

    van Wezel, Richard J. A.

    2013-01-01

    Visual motion on the macaque retina is processed by direction- and speed-selective neurons in extrastriate middle temporal cortex (MT). There is strong evidence for a link between the activity of these neurons and direction perception. However, there is conflicting evidence for a link between speed selectivity of MT neurons and speed perception. Here we study this relationship by using a strong perceptual illusion in speed perception: when two transparently superimposed dot patterns move in opposite directions, their apparent speed is much larger than the perceived speed of a single pattern moving at that physical speed. Moreover, the sensitivity for speed discrimination is reduced for such bidirectional patterns. We first confirmed these behavioral findings in human subjects and extended them to a monkey subject. Second, we determined speed tuning curves of MT neurons to bidirectional motion and compared these to speed tuning curves for unidirectional motion. Consistent with previous reports, the response to bidirectional motion was often reduced compared with unidirectional motion at the preferred speed. In addition, we found that tuning curves for bidirectional motion were shifted to lower preferred speeds. As a consequence, bidirectional motion of some speeds typically evoked larger responses than unidirectional motion. Third, we showed that these changes in neural responses could explain changes in speed perception with a simple labeled line decoder. These data provide new insight into the encoding of transparent motion patterns and provide support for the hypothesis that MT activity can be decoded for speed perception with a labeled line model. PMID:23926031

  16. Optimal inference explains the perceptual coherence of visual motion stimuli

    PubMed Central

    Hedges, James H.; Stocker, Alan A.; Simoncelli, Eero P.

    2013-01-01

    The local spatiotemporal pattern of light on the retina is often consistent with a single translational velocity which may also be interpreted as a superposition of spatial patterns translating with different velocities. Human perception reflects such interpretations, as can be demonstrated using stimuli constructed from a superposition of two drifting gratings. Depending on a variety of parameters, these stimuli may be perceived as a coherently moving plaid pattern or as two transparent gratings moving in different directions. Here, we propose a quantitative model that explains how and why such interpretations are selected. An observer’s percept corresponds to the most probable interpretation of noisy measurements of local image motion, based on separate prior beliefs about the speed and singularity of visual motion. This model accounts for human perceptual interpretations across a broad range of angles and speeds. With optimized parameters, its components are consistent with previous results in motion perception. PMID:21602554

  17. Where do we store the memory representations that guide attention?

    PubMed Central

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

    2013-01-01

    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

  18. Individual differences in visual search: relationship to autistic traits, discrimination thresholds, and speed of processing.

    PubMed

    Brock, Jon; Xu, Jing Y; Brooks, Kevin R

    2011-01-01

    Enhanced visual search is widely reported in autism. Here we note a similar advantage for university students self-reporting higher levels of autism-like traits. Contrary to prevailing theories of autism, performance was not associated with perceptual-discrimination thresholds for the same stimuli, but was associated with inspection-time threshold--a measure of speed of perceptual processing. Enhanced visual search in autism may, therefore, at least partially be explained by faster speed of processing. PMID:21936301

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

    PubMed Central

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

    2014-01-01

    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

  20. 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

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

    2012-01-01

    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,…

  1. Collapse models and perceptual processes

    NASA Astrophysics Data System (ADS)

    Carlo Ghirardi, Gian; Romano, Raffaele

    2014-04-01

    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.

  2. Building online brand perceptual map.

    PubMed

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

    2008-10-01

    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

  3. WAIS-IV Verbal Comprehension Index and Perceptual Reasoning Index performance is unaffected by cold-pressor pain induction.

    PubMed

    Etherton, Joseph

    2015-01-01

    Cognitive complaints are frequently reported by patients with chronic pain, but studies of the effects of pain on different forms of cognition have been inconsistent. In two studies, cold-pressor pain was induced in nonclinical undergraduate volunteers who, under normal conditions, took Verbal Comprehension Index (VCI) subtests (Study 1, n=57) or Perceptual Reasoning Index (PRI) subtests (Study 2, n=59) followed by a different VCI or PRI subtest taken during either cold-pressor pain induction or a nonpainful control condition. Pain was not associated with significant reduction in subtest scaled score performance. Results indicate that cold-pressor pain in nonclinical volunteers does not impair Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) VCI or PRI performance and suggest that pain per se should not be expected to substantially influence these cognitive abilities. Viewed together with previous Processing Speed Index and Working Memory Index studies, no cognitive or intellectual functions measured by the WAIS-IV are affected by induced pain. Generalizability of these findings may be limited by the fact that patients with chronic pain may differ in their pain experience from nonclinical volunteers with induced pain. PMID:25529592

  4. Perceptual Training Strongly Improves Visual Motion Perception in Schizophrenia

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  5. The formation of linked perceptual classes.

    PubMed Central

    Fields, Lanny; Matneja, Priya; Varelas, Antonios; Belanich, James; Fitzer, Adrienne; Shamoun, Kim

    2002-01-01

    Multiple-exemplar training with stimuli in four domains induced two new fill-based (A1' and A2') and satellite-image-based (B1' and B2') perceptual classes. Conditional discriminations were established between the endpoints of the A1' and B1' classes as well as the A2' and B2' classes. The emergence of linked perceptual classes was evaluated by the performances occasioned by nine cross-class probes that contained fill variants as samples and satellite variants as comparisons, along with nine other cross-class probes that consisted of satellite variants as samples and fill variants as comparisons. The 18 probes were first presented serially and then concurrently. Class-consistent responding indicated the emergence of linked perceptual classes. Of the linked perceptual classes, 70% emerged during the initial serial test. An additional 20% of the linked perceptual classes emerged during the subsequently presented concurrent test block. Thus, linked perceptual classes emerged on an immediate or delayed basis. Linked perceptual classes, then, share structural and fuctional similarities with equivalence classes, generalized equivalence classes, cross-modal classes, and complex maturally occurring categories, and may clarify processes such as intersensory perception. PMID:12507004

  6. A memory advantage for property.

    PubMed

    DeScioli, Peter; Rosa, Nicole M; Gutchess, Angela H

    2015-01-01

    People's access to resources depends on their status as the owner of particular items. To respect property, people need to remember who owns which objects. We test the hypothesis that people possess enhanced memory for ownership relations compared to unrelated objects. Participants viewed a sequence of 10 person-object pairs before completing a surprise associative memory test in which they matched each person with the previously paired object. We varied the description of the person-object pairs in the instructions. Across three experiments, participants showed better recall when the person was described as the owner of the object compared to being unrelated. Furthermore, memory for property was better than a physical relation (bumping), whereas it did not differ from mental relations (wanting and thinking). These patterns were observed both for memory of items (Experiments 1 and 2) and perceptual details (Experiment 3). We discuss implications for how people remember other people's property. PMID:25986536

  7. Perceptual skill in soccer: implications for talent identification and development.

    PubMed

    Williams, A M

    2000-09-01

    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 in soccer. Similarly, experts use their knowledge of situational probabilities (i.e. expectations) to anticipate future events. They have a better than average idea of what is likely to happen given a particular set of circumstances. Also, proficiency-related differences in visual search strategy are observed. Skilled players use their superior knowledge to control the eye movement patterns necessary for seeking and picking up important sources of information. The nature of the task plays an important role in constraining the type of search used. Skilled soccer players use different search strategies when viewing the whole field (i.e. 11 vs 11 situations) compared with micro-states of the game (i.e. 1 vs 1, 3 vs 3 situations). Visual search behaviour also differs between defensive and offensive plays. These observations have implications for the development of perceptual training programmes and the identification of potential elite soccer players. PMID:11043899

  8. Development of Auditory-Vocal Perceptual Skills in Songbirds

    PubMed Central

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

    2012-01-01

    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

  9. Perceptually oriented hypnosis: cross-cultural perspectives.

    PubMed

    Woodard, Fredrick James

    2005-08-01

    Literature is reviewed and summarized relevant to present cross-cultural, shamanic, and spiritual aspects of hypnosis. Explanations are offered within the framework of Woodard's theory of Perceptually Oriented Hypnosis. Research on cross-cultural aspects of hypnosis could enhance understanding of phenomenological and perceptual aspects of hypnosis, increase knowledge of hypnotic phenomena, and expand understanding of perceptual awareness. A summary of the qualitative research methodologies to enhance understanding of multicultural hypnotic experiences is presented. This groundwork provides for further exploration of cross-cultural hypnosis. Surprisingly, some suggestions have remained underutilized or not published. PMID:16279318

  10. Procedural learning in perceptual categorization.

    PubMed

    Ashby, F Gregory; Ell, Shawn W; Waldron, Elliott M

    2003-10-01

    In two experiments, observers learned two types of category structures: those in which perfect accuracy could be achieved via some explicit rule-based strategy and those in which perfect accuracy required integrating information from separate perceptual dimensions at some predecisional stage. At the end of training, some observers were required to switch their hands on the response keys, whereas the assignment of categories to response keys was switched for other observers. With the rule-based category structures, neither change in response instructions interfered with categorization accuracy. However, with the information-integration structures, switching response key assignments interfered with categorization performance, but switching hands did not. These results are consistent with the hypothesis that abstract category labels are learned in rule-based categorization, whereas response positions are learned in information-integration categorization. The association to response positions also supports the hypothesis of a procedural-learning-based component to information integration categorization. PMID:14704026

  11. Defensive engagement and perceptual enhancement

    PubMed Central

    Keil, Andreas; Bradley, Margaret M.; Ihssen, Niklas; Heim, Sabine; Vila, Jaime; Guerra, Pedro; Lang, Peter J.

    2010-01-01

    We tested whether visual cortical sensitivity to external cues in the context of an acute defensive reaction is heightened or attenuated. A strong cardiac defense (fear) response was elicited by presenting an abrupt, loud acoustic stimulus following a 10-minute period of quiescence. Electrocortical responses to aversive and neutral pictures following defensive stimulus onset were measured using dense-array EEG. Pictures were flickered at 12.5 Hz to evoke steady-state visual evoked potentials (ssVEP), which can be reliably extracted on the basis of single trials. Visual cortical activity indexing perceptual processing was substantially heightened when pictures were shown in temporal proximity to (i.e., 5 second after) the defense stimulus. Replicating previous studies, aversive visual stimuli were associated with enhanced ssVEP amplitude, compared to neutral stimuli. Acute defense facilitates visual perception of external cues and preserves accurate discrimination between threatening and safe cues. PMID:20713075

  12. Probing perceptual decisions in rodents

    PubMed Central

    Carandini, Matteo; Churchland, Anne K

    2014-01-01

    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

  13. Using a multinomial tree model for detecting mixtures in perceptual detection

    PubMed Central

    Chechile, Richard A.

    2014-01-01

    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

  14. Interdisciplinary Adventures in Perceptual Ecology

    NASA Astrophysics Data System (ADS)

    Bocast, Christopher S.

    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.

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

    ERIC Educational Resources Information Center

    Wilkinson, Krista M.; McIlvane, William J.

    2013-01-01

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

  16. Selection from visual persistence by perceptual groups and category membership.

    PubMed

    Merikle, P M

    1980-09-01

    Following Sperling, the nature of the representation of visual information during visual persistence has been investigated by comparing partial-report (PR) and whole-report (WR) estimates of available information. A PR superiority is considered evidence for the representation of the cued stimulus dimension in visual persistence. In general, PR cues based on a physical characteristic produce a PR superiority, but PR cues based on a category distinction give no higher estimates of available information than is obtained with WR. These findings have been used to support an interpretation of visual persistence based upon a storage system metaphor (e.g., iconic memory), whereby a critical characteristic of the stored information is its "literal" precategorical nature. The present experiments explored whether there are reasonable alternative explanations for the fact that only physical PR cues typical produced a PR superiority. Experiments 1 and 2 demonstrate that the effectiveness of physical PR cues depends upon the "goodness' of the perceptual groups defined by the cued dimension. Perceptual grouping within multi-letter displays was varied according to the principles of proximity (Exp. 1) and similarity (Exp. 2), and the results showed greater PR superiorities when the demand characteristics of the cues were compatible with the implied perceptual groups in the displays. Experiments 3 and 4 establish that PR cues based upon a category distinction (letter-digit) produce a PR superiority when both cue onset latency and cue uncertainty are equated across PR and WR conditions. Circular alphanumeric displays were used, and category PR cues and WR cues were either presented in separate trial blocks (Exp. 3) or intermixed at two possible cue delays relative to display onset (-1000 msec or 0 msec). A PR superiority was found in all conditions. In addition, Experiment 5 shows that the magnitude of this category PR superiority decreased systematically with increases in cue delay (-900 msec, -300 msec, +300 msec, and +900 msec), and in Experiment 6, it was found that the PR superiorities for both physical and category cues decrease at comparable rates with increased cue delay. Since perceptual grouping influences the effectiveness of physical PR cues and category PR cues produce a PR superiority under appropriate conditions, the results question the validity of interpretions of visual persistence that imply the existence of a literal, precategorical storage system. It is suggested that a multichannel view of the visual system provides a more adquate theoretical conceptualization of visual persistence. PMID:6447189

  17. Prior expectations facilitate metacognition for perceptual decision.

    PubMed

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

    2015-09-01

    The influential framework of 'predictive processing' suggests that prior probabilistic expectations influence, or even constitute, perceptual contents. This notion is evidenced by the facilitation of low-level perceptual processing by expectations. However, whether expectations can facilitate high-level components of perception remains unclear. We addressed this question by considering the influence of expectations on perceptual metacognition. To isolate the effects of expectation from those of attention we used a novel factorial design: expectation was manipulated by changing the probability that a Gabor target would be presented; attention was manipulated by instructing participants to perform or ignore a concurrent visual search task. We found that, independently of attention, metacognition improved when yes/no responses were congruent with expectations of target presence/absence. Results were modeled under a novel Bayesian signal detection theoretic framework which integrates bottom-up signal propagation with top-down influences, to provide a unified description of the mechanisms underlying perceptual decision and metacognition. PMID:25973773

  18. Robot Partners: Collaborative Perceptual Robotic Systems

    E-print Network

    Little, Jim

    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

  19. Cognitive Perceptual Deficits in Elderly Delirious Patients 

    E-print Network

    McGrory, Sarah

    2008-06-27

    Objectives: The aim was to examine the cognitive deficits caused by delirium, with the specific goal of investigating the prevalence of cognitive perceptual deficits. To ensure this deficit is not a result of a general cognitive impairment...

  20. Perceptual Evaluation of Video-Realistic Speech

    E-print Network

    Geiger, Gadi

    2003-02-28

    abstract With many visual speech animation techniques now available, there is a clear need for systematic perceptual evaluation schemes. We describe here our scheme and its application to a new video-realistic ...

  1. Power reduction of multiple disks using dynamic cache resizing and speed control

    Microsoft Academic Search

    Le Cai; Yung-hsiang Lu

    2006-01-01

    This paper presents an energy-conservation method for mul- tiple disks and their cache memory. Our method period- ically resizes the cache memory and controls the rotation speeds under performance constraints. The cache memory stores the data from the disks for reuse. Enlarging the cache memory reduces disk accesses and disk utilization. This al- lows the disks to reduce their speeds

  2. Main Memory Database Systems: An Overview

    Microsoft Academic Search

    Hector Garcia-molina; Kenneth Salem

    1992-01-01

    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

  3. Is perceptual space inherently non-Euclidean?

    PubMed

    Fernandez, Julian Martin; Farell, Bart

    2009-04-01

    It is often assumed that the space we perceive is Euclidean, although this idea has been challenged by many authors. Here we show that, if spatial cues are combined as described by Maximum Likelihood Estimation, Bayesian, or equivalent models, as appears to be the case, then Euclidean geometry cannot describe our perceptual experience. Rather, our perceptual spatial structure would be better described as belonging to an arbitrarily curved Riemannian space. PMID:20161280

  4. Can Attention be Divided Between Perceptual Groups?

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

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

  5. Conceptual and perceptual priming and dissociation in chronic posttraumatic stress disorder.

    PubMed

    Lyttle, Nigel; Dorahy, Martin J; Hanna, Donncha; Huntjens, Rafaële J C

    2010-11-01

    Cognitive models of posttraumatic stress disorder (PTSD) assert that memory processes play a significant role in PTSD (see e.g., Ehlers & Clark, 2000). Intrusive reexperiencing in PTSD has been linked to perceptual processing of trauma-related material with a corresponding hypothesized lack of conceptual processing. In an experimental study that included clinical participants with and without PTSD (N = 50), perceptual priming and conceptual priming for trauma-related, general threat, and neutral words were investigated in a population with chronic trauma-induced complaints as a result of the Troubles in Northern Ireland. The study used a new version of the word-stem completion task (Michael, Ehlers, & Halligan, 2005) and a word-cue association task. It also assessed the role of dissociation in threat processing. Further evidence of enhanced perceptual priming in PTSD for trauma stimuli was found, along with evidence of lack of conceptual priming for such stimuli. Furthermore, this pattern of priming for trauma-related words was associated with PTSD severity, and state dissociation and PTSD group made significant contributions to predicting perceptual priming for trauma words. The findings shed light on the importance of state dissociation in trauma-related information processing and posttraumatic symptoms. PMID:21090878

  6. Poor Anchoring Limits Dyslexics' Perceptual, Memory, and Reading Skills

    ERIC Educational Resources Information Center

    Oganian, Yulia; Ahissar, Merav

    2012-01-01

    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,…

  7. MESO: Perceptual Memory to Support Online Learning in Adaptive Software

    E-print Network

    McKinley, Philip K.

    in such systems, which must learn how and when to invoke corrective actions based on past experi- ence. This paper that a system This work was supported in part by the U.S. Department of the Navy, Office of Naval Research application that can imitatively learn [1, 13] how to adapt to changing network conditions. Due to space

  8. Movement and perceptual strategies to intercept virtual sound sources

    PubMed Central

    Komeilipoor, Naeem; Rodger, Matthew W. M.; Cesari, Paola; Craig, Cathy M.

    2015-01-01

    To intercept a moving object, one needs to be in the right place at the right time. In order to do this, it is necessary to pick up and use perceptual information that specifies the time to arrival of an object at an interception point. In the present study, we examined the ability to intercept a laterally moving virtual sound object by controlling the displacement of a sliding handle and tested whether and how the interaural time difference (ITD) could be the main source of perceptual information for successfully intercepting the virtual object. The results revealed that in order to accomplish the task, one might need to vary the duration of the movement, control the hand velocity and time to reach the peak velocity (speed coupling), while the adjustment of movement initiation did not facilitate performance. Furthermore, the overall performance was more successful when subjects employed a time-to-contact (tau) coupling strategy. This result shows that prospective information is available in sound for guiding goal-directed actions. PMID:25999805

  9. Movement and perceptual strategies to intercept virtual sound sources.

    PubMed

    Komeilipoor, Naeem; Rodger, Matthew W M; Cesari, Paola; Craig, Cathy M

    2015-01-01

    To intercept a moving object, one needs to be in the right place at the right time. In order to do this, it is necessary to pick up and use perceptual information that specifies the time to arrival of an object at an interception point. In the present study, we examined the ability to intercept a laterally moving virtual sound object by controlling the displacement of a sliding handle and tested whether and how the interaural time difference (ITD) could be the main source of perceptual information for successfully intercepting the virtual object. The results revealed that in order to accomplish the task, one might need to vary the duration of the movement, control the hand velocity and time to reach the peak velocity (speed coupling), while the adjustment of movement initiation did not facilitate performance. Furthermore, the overall performance was more successful when subjects employed a time-to-contact (tau) coupling strategy. This result shows that prospective information is available in sound for guiding goal-directed actions. PMID:25999805

  10. The working memory Ponzo illusion: Involuntary integration of visuospatial information stored in visual working memory.

    PubMed

    Shen, Mowei; Xu, Haokui; Zhang, Haihang; Shui, Rende; Zhang, Meng; Zhou, Jifan

    2015-08-01

    Visual working memory (VWM) has been traditionally viewed as a mental structure subsequent to visual perception that stores the final output of perceptual processing. However, VWM has recently been emphasized as a critical component of online perception, providing storage for the intermediate perceptual representations produced during visual processing. This interactive view holds the core assumption that VWM is not the terminus of perceptual processing; the stored visual information rather continues to undergo perceptual processing if necessary. The current study tests this assumption, demonstrating an example of involuntary integration of the VWM content, by creating the Ponzo illusion in VWM: when the Ponzo illusion figure was divided into its individual components and sequentially encoded into VWM, the temporally separated components were involuntarily integrated, leading to the distorted length perception of the two horizontal lines. This VWM Ponzo illusion was replicated when the figure components were presented in different combinations and presentation order. The magnitude of the illusion was significantly correlated between VWM and perceptual versions of the Ponzo illusion. These results suggest that the information integration underling the VWM Ponzo illusion is constrained by the laws of visual perception and similarly affected by the common individual factors that govern its perception. Thus, our findings provide compelling evidence that VWM functions as a buffer serving perceptual processes at early stages. PMID:25912893

  11. Co-occurring disorders: a possible key to visual perceptual deficits in children with developmental coordination disorder?

    PubMed

    Crawford, S G; Dewey, D

    2008-02-01

    A study was conducted to examine how visual perceptual functioning in children with DCD may be influenced by co-occurring learning problems such as reading disabilities (RD) and/or attention deficit hyperactivity disorder (ADHD). Participants included seven groups of children: 27 children with DCD only, 11 with ADHD only, 14 with RD only, 63 with DCD and at least one other disorder (i.e., DCD + ADHD, DCD + RD, DCD + ADHD + RD), and 73 typically developing controls. Visual perceptual skills were assessed using the Test of Visual Perceptual Skills (TVPS) and the Rey Osterreith Complex Figure (ROCF; copy and delayed recall). Children with DCD and at least one other disorder were found to have impairments on the TVPS compared to children with DCD only, ADHD only, and typically developing controls, particularly on subtests assessing visual memory. On the ROCF, children with DCD and at least one other disorder scored significantly lower than children with ADHD only or RD only. Children with DCD plus one other disorder were then subdivided into three groups: DCD + ADHD, DCD + RD, and DCD + ADHD + RD and compared to children with DCD only, ADHD only, and RD only. Results indicated that children with DCD + ADHD + RD had significant impairments on the TVPS compared to children with DCD only and children with ADHD only. On the ROCF, children with DCD + ADHD + RD scored significantly lower than all of the groups, except the DCD+RD group. These findings suggest that DCD on its own is not associated with visual perceptual problems; rather, it is the presence of co-occurring disorders that is a possible key to visual perceptual deficits in children with DCD. The number of co-occurring disorders present with DCD is associated with the severity of the visual perceptual dysfunction. Deficits in visual memory skills appear to be a specific area of difficulty for children with DCD and co-occurring RD and/or ADHD. PMID:18192047

  12. Accurate forced-choice recognition without awareness of memory retrieval

    PubMed Central

    Voss, Joel L.; Baym, Carol L.; Paller, Ken A.

    2008-01-01

    Recognition confidence and the explicit awareness of memory retrieval commonly accompany accurate responding in recognition tests. Memory performance in recognition tests is widely assumed to measure explicit memory, but the generality of this assumption is questionable. Indeed, whether recognition in nonhumans is always supported by explicit memory is highly controversial. Here we identified circumstances wherein highly accurate recognition was unaccompanied by hallmark features of explicit memory. When memory for kaleidoscopes was tested using a two-alternative forced-choice recognition test with similar foils, recognition was enhanced by an attentional manipulation at encoding known to degrade explicit memory. Moreover, explicit recognition was most accurate when the awareness of retrieval was absent. These dissociations between accuracy and phenomenological features of explicit memory are consistent with the notion that correct responding resulted from experience-dependent enhancements of perceptual fluency with specific stimuli—the putative mechanism for perceptual priming effects in implicit memory tests. This mechanism may contribute to recognition performance in a variety of frequently-employed testing circumstances. Our results thus argue for a novel view of recognition, in that analyses of its neurocognitive foundations must take into account the potential for both (1) recognition mechanisms allied with implicit memory and (2) recognition mechanisms allied with explicit memory. PMID:18519546

  13. Accurate forced-choice recognition without awareness of memory retrieval.

    PubMed

    Voss, Joel L; Baym, Carol L; Paller, Ken A

    2008-06-01

    Recognition confidence and the explicit awareness of memory retrieval commonly accompany accurate responding in recognition tests. Memory performance in recognition tests is widely assumed to measure explicit memory, but the generality of this assumption is questionable. Indeed, whether recognition in nonhumans is always supported by explicit memory is highly controversial. Here we identified circumstances wherein highly accurate recognition was unaccompanied by hallmark features of explicit memory. When memory for kaleidoscopes was tested using a two-alternative forced-choice recognition test with similar foils, recognition was enhanced by an attentional manipulation at encoding known to degrade explicit memory. Moreover, explicit recognition was most accurate when the awareness of retrieval was absent. These dissociations between accuracy and phenomenological features of explicit memory are consistent with the notion that correct responding resulted from experience-dependent enhancements of perceptual fluency with specific stimuli--the putative mechanism for perceptual priming effects in implicit memory tests. This mechanism may contribute to recognition performance in a variety of frequently-employed testing circumstances. Our results thus argue for a novel view of recognition, in that analyses of its neurocognitive foundations must take into account the potential for both (1) recognition mechanisms allied with implicit memory and (2) recognition mechanisms allied with explicit memory. PMID:18519546

  14. Perceived visual speed constrained by image segmentation

    NASA Technical Reports Server (NTRS)

    Verghese, P.; Stone, L. S.

    1996-01-01

    Little is known about how or where the visual system parses the visual scene into objects or surfaces. However, it is generally assumed that the segmentation and grouping of pieces of the image into discrete entities is due to 'later' processing stages, after the 'early' processing of the visual image by local mechanisms selective for attributes such as colour, orientation, depth, and motion. Speed perception is also thought to be mediated by early mechanisms tuned for speed. Here we show that manipulating the way in which an image is parsed changes the way in which local speed information is processed. Manipulations that cause multiple stimuli to appear as parts of a single patch degrade speed discrimination, whereas manipulations that perceptually divide a single large stimulus into parts improve discrimination. These results indicate that processes as early as speed perception may be constrained by the parsing of the visual image into discrete entities.

  15. Pupil size tracks perceptual content and surprise.

    PubMed

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

    2015-04-01

    Changes in pupil size at constant light levels reflect the activity of neuromodulatory brainstem centers that control global brain state. These endogenously driven pupil dynamics can be synchronized with cognitive acts. For example, the pupil dilates during the spontaneous switches of perception of a constant sensory input in bistable perceptual illusions. It is unknown whether this pupil dilation only indicates the occurrence of perceptual switches, or also their content. Here, we measured pupil diameter in human subjects reporting the subjective disappearance and re-appearance of a physically constant visual target surrounded by a moving pattern ('motion-induced blindness' illusion). We show that the pupil dilates during the perceptual switches in the illusion and a stimulus-evoked 'replay' of that illusion. Critically, the switch-related pupil dilation encodes perceptual content, with larger amplitude for disappearance than re-appearance. This difference in pupil response amplitude enables prediction of the type of report (disappearance vs. re-appearance) on individual switches (receiver-operating characteristic: 61%). The amplitude difference is independent of the relative durations of target-visible and target-invisible intervals and subjects' overt behavioral report of the perceptual switches. Further, we show that pupil dilation during the replay also scales with the level of surprise about the timing of switches, but there is no evidence for an interaction between the effects of surprise and perceptual content on the pupil response. Taken together, our results suggest that pupil-linked brain systems track both the content of, and surprise about, perceptual events. PMID:25754528

  16. Perceptually adapted MPEG video encoding

    NASA Astrophysics Data System (ADS)

    Bordes, Philippe; Guillotel, Philippe

    2000-06-01

    In picture quality assessment, the amount of distortion perceived by a human observer differs from one region to another according to its particular local content. This subjective perception can be explained/predicted by considering some simple psychovisual properties (masking) of the Human Visual System (HVS). We have implemented a HVS model based on a pyramid decomposition for extracting the spatial frequencies, associated with a multi-resolution motion representation. Then the visibility of the decoded errors is computed by exploiting the Kelly's contrast sensitivity spatio-velocity model. The resulting data is called a 'Quality-map.' Special attention has been paid to temporal/moving effects since, in the case of video sequences, motion strongly influences the subjective quality assessment. The quality of the motion information is thus preponderant. In the second part, two possible uses of these psychovisual properties for improving MPEG video encoding performances are depicted: (1) The pre-processing of the pictures to remove non-visible information using a motion adapted filtering. This process is efficient in term of bits saved and degradation is not significant especially on consumer electronic TV sets. (2) A perceptual quantizer based on a local adaptation scheme in order to obtain Quality-maps as uniform as possible (homogeneous perceived distortion), at constant bit-rate. Further improvements have been considered, especially when the viewer is tracking a moving object in the scene.

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

    PubMed Central

    Sanchez, Daniel J.; Reber, Paul J.

    2012-01-01

    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

  18. Perceptual and Motor Inhibition in Adolescents/Young Adults with Childhood-Diagnosed ADHD

    PubMed Central

    Bedard, Anne-Claude V.; Trampush, Joey W.; Newcorn, Jeffrey H.; Halperin, Jeffrey M.

    2010-01-01

    Objective This study examined perceptual and motor inhibition in a longitudinal sample of adolescents/young adults who were diagnosed with ADHD in childhood, and as a function of the relative persistence of ADHD. Method Ninety-eight participants diagnosed with ADHD in childhood were re-evaluated approximately 10 years later. Eighty-five never-ADHD controls similar in age, IQ, sociodemographic background, and gender distribution served as a comparison group. Participants were administered a psychiatric interview and the Stimulus and Response Conflict Tasks (Nassauer & Halperin, 2003). Results Participants with childhood ADHD demonstrated slower and less accurate responses to both control and conflict conditions relative to the comparison group, as well as more variable responses in both conditions of the motor inhibition task; there was no specific effect of childhood ADHD on perceptual or motor inhibition. ADHD persisters and partial remitters did not differ in overall accuracy, speed or variability in responding, but relative to partial remitters, persisters demonstrated greater slowing in response to perceptual conflict. Conclusions These findings are consistent with theories positing state regulation, but not inhibitory control deficits in the etiology of ADHD, and suggest that improved perceptual inhibition may be associated with better outcome for ADHD. PMID:20604617

  19. Capacity-Speed Relationships in Prefrontal Cortex

    E-print Network

    Prabhakaran, Vivek

    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 ...

  20. Speaker's voice as a memory cue.

    PubMed

    Campeanu, Sandra; Craik, Fergus I M; Alain, Claude

    2015-02-01

    Speaker's voice occupies a central role as the cornerstone of auditory social interaction. Here, we review the evidence suggesting that speaker's voice constitutes an integral context cue in auditory memory. Investigation into the nature of voice representation as a memory cue is essential to understanding auditory memory and the neural correlates which underlie it. Evidence from behavioral and electrophysiological studies suggest that while specific voice reinstatement (i.e., same speaker) often appears to facilitate word memory even without attention to voice at study, the presence of a partial benefit of similar voices between study and test is less clear. In terms of explicit memory experiments utilizing unfamiliar voices, encoding methods appear to play a pivotal role. Voice congruency effects have been found when voice is specifically attended at study (i.e., when relatively shallow, perceptual encoding takes place). These behavioral findings coincide with neural indices of memory performance such as the parietal old/new recollection effect and the late right frontal effect. The former distinguishes between correctly identified old words and correctly identified new words, and reflects voice congruency only when voice is attended at study. Characterization of the latter likely depends upon voice memory, rather than word memory. There is also evidence to suggest that voice effects can be found in implicit memory paradigms. However, the presence of voice effects appears to depend greatly on the task employed. Using a word identification task, perceptual similarity between study and test conditions is, like for explicit memory tests, crucial. In addition, the type of noise employed appears to have a differential effect. While voice effects have been observed when white noise is used at both study and test, using multi-talker babble does not confer the same results. In terms of neuroimaging research modulations, characterization of an implicit memory effect reflective of voice congruency is currently lacking. PMID:25173195

  1. Decoding oscillatory representations and mechanisms in memory.

    PubMed

    Jafarpour, A; Horner, A J; Fuentemilla, L; Penny, W D; Duzel, E

    2013-03-01

    A fundamental goal in memory research is to understand how information is represented in distributed brain networks and what mechanisms enable its reactivation. It is evident that progress towards this goal will greatly benefit from multivariate pattern classification (MVPC) techniques that can decode representations in brain activity with high temporal resolution. Recently, progress along these lines has been achieved by applying MVPC to neural oscillations recorded with electroencephalography (EEG) and magnetoencephalography (MEG). We highlight two examples of methodological approaches for MVPC of EEG and MEG data that can be used to study memory function. The first example aims at understanding the dynamic neural mechanisms that enable reactivation of memory representations, i.e., memory replay; we discuss how MVPC can help uncover the physiological mechanisms underlying memory replay during working memory maintenance and episodic memory. The second example aims at understanding representational differences between various types of memory, such as perceptual priming and conscious recognition memory. We also highlight the conceptual and methodological differences between these two examples. Finally, we discuss potential future applications for MVPC of EEG/MEG data in studies of memory. We conclude that despite its infancy and existing methodological challenges, MVPC of EEG and MEG data is a powerful tool with which to assess mechanistic models of memory. PMID:22561180

  2. A Unified View on Speeded Categorization Hongbin Gu 1

    E-print Network

    Ji, Chuanshu

    in speeded perceptual categorization (or equivalently, classification) has been developed rapidly in recent is to decide which category a given stimulus i belongs to, based on the information accumulated over time. Since stimulus i is fixed in this work, we will suppress symbol i in most expressions except for those

  3. The limits of arousal's memory impairing effects on nearby information

    PubMed Central

    Mather, Mara; Gorlick, Marissa; Nesmith, Kathryn

    2009-01-01

    Showing an arousing central stimulus in a scene often leads to enhanced memory for the arousing central information and impaired memory for peripheral details. However, it is not clear from previous work whether arousing stimuli impair memory for all non-arousing nearby information or just background information. In several experiments, we tested how emotionally arousing pictures affect memory for nearby pictures and for background information. We found that when two pictures were presented together, having one of the pictures be arousing did not affect item and location memory for the other picture. In contrast, an arousing picture impaired memory for a background pattern. These findings suggest that arousal impairs memory for information that is the target of perceptual suppression, such as background information when there is a figure-ground distinction, but does not impair memory for other foreground information. PMID:19827704

  4. Perceptual Coding of Recorded Telemanipulation Sessions Fernanda Brandi, Eckehard Steinbach

    E-print Network

    Steinbach, Eckehard

    overall haptic and visual performances. Categories and Subject Descriptors E.4 [Coding and Information, Performance Keywords data reduction, haptics, perceptual coding, playback, signal compression, signalPerceptual Coding of Recorded Telemanipulation Sessions Fernanda Brandi, Eckehard Steinbach

  5. Error-Resilient Perceptual Coding for Networked Haptic Interaction

    E-print Network

    Steinbach, Eckehard

    Error-Resilient Perceptual Coding for Networked Haptic Interaction Fernanda Brandi, Julius Kammerl, Reliability Keywords haptic technology and interaction, haptic communication, perceptual coding, telepresence.brandi, kammerl, eckehard.steinbach}@tum.de ABSTRACT The performance of haptic interaction across communication

  6. Perceptually Robust Traffic Control in Distributed Haptic Virtual Environments

    E-print Network

    Steinbach, Eckehard

    deteriorating haptic feedback quality. Keywords: Weber's law, perceptual coding, distributed haptics 1Perceptually Robust Traffic Control in Distributed Haptic Virtual Environments Clemens Schuwerk present a traffic control scheme for server to client communication in distributed haptic virtual

  7. Conceptual and perceptual encoding instructions differently affect event recall.

    PubMed

    García-Bajos, Elvira; Migueles, Malen; Aizpurua, Alaitz

    2014-11-01

    When recalling an event, people usually retrieve the main facts and a reduced proportion of specific details. The objective of this experiment was to study the effects of conceptually and perceptually driven encoding in the recall of conceptual and perceptual information of an event. The materials selected for the experiment were two movie trailers. To enhance the encoding instructions, after watching the first trailer participants answered conceptual or perceptual questions about the event, while a control group answered general knowledge questions. After watching the second trailer, all of the participants completed a closed-ended recall task consisting of conceptual and perceptual items. Conceptual information was better recalled than perceptual details and participants made more perceptual than conceptual commission errors. Conceptually driven processing enhanced the recall of conceptual information, while perceptually driven processing not only did not improve the recall of descriptive details, but also damaged the standard conceptual/perceptual recall relationship. PMID:24718934

  8. Referred Visual Sensations: Rapid Perceptual Elongation after Visual Cortical Deprivation

    E-print Network

    Baker, Chris I.

    Visual perceptual distortion (i.e., elongation) has been demonstrated in a single case study after several months of cortical deprivation after a stroke. Here we asked whether similar perceptual elongation can be observed ...

  9. Effects of Aging on True and False Memory Formation: An fMRI Study

    ERIC Educational Resources Information Center

    Dennis, Nancy A.; Kim, Hongkeun; Cabeza, Roberto

    2007-01-01

    Compared to young, older adults are more likely to forget events that occurred in the past as well as remember events that never happened. Previous studies examining false memories and aging have shown that these memories are more likely to occur when new items share perceptual or semantic similarities with those presented during encoding. It is…

  10. 2012. 1 75 Cognitive Computing I: Multisensory Perceptual

    E-print Network

    ) (cognitive computing) . , , , , , , , , , , , . (cognitive science2012. 1 75 Cognitive Computing I: Multisensory Perceptual Intelligence - * * 1. 1) (information technology) (cognitive information systems

  11. Dazzle Camouflage Affects Speed Perception

    PubMed Central

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

    2011-01-01

    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

  12. Quantum-Computation for Perceptual Control Architecture

    NASA Astrophysics Data System (ADS)

    Ivancevic, Vladimir G.; Reid, Darryn J.

    2015-11-01

    In this Chapter, we propose a quantum-dynamical modeling approach to Perceptual Control Architecture, using large networks of Josephson Junctions and their category-theoretic generalizations with fuzzy associative functors Our approach provides the basis for composing modular multi-layered perceptual control architectures using Josephson Junction Networks, employing intuitively appealing category-theoretic abstractions to hide the algebraic details from the designer while nonetheless being able to rigorously ensure functional composition correctness. That is, our approach ensures that Josephson Junction Networks, as a modeling primitive, can be composed into formally correct multi-layered perceptual control architectures, while hiding the underlying algebraic systems of equations from the designer under a blanket of category-theoretic abstraction.

  13. Action-Specific Disruption of Perceptual Confidence

    PubMed Central

    Maniscalco, Brian; Ko, Yoshiaki; Amendi, Namema; Ro, Tony; Lau, Hakwan

    2015-01-01

    Theoretical models of perception assume that confidence is related to the quality or strength of sensory processing. Counter to this intuitive view, we showed in the present research that the motor system also contributes to judgments of perceptual confidence. In two experiments, we used transcranial magnetic stimulation (TMS) to manipulate response-specific representations in the premotor cortex, selectively disrupting postresponse confidence in visual discrimination judgments. Specifically, stimulation of the motor representation associated with the unchosen response reduced confidence in correct responses, thereby reducing metacognitive capacity without changing visual discrimination performance. Effects of TMS on confidence were observed when stimulation was applied both before and after the response occurred, which suggests that confidence depends on late-stage metacognitive processes. These results place constraints on models of perceptual confidence and metacognition by revealing that action-specific information in the premotor cortex contributes to perceptual confidence. PMID:25425059

  14. Angular relation of axes in perceptual space

    NASA Technical Reports Server (NTRS)

    Bucher, Urs

    1992-01-01

    The geometry of perceptual space needs to be known to model spatial orientation constancy or to create virtual environments. To examine one main aspect of this geometry, the angular relation between the three spatial axes was measured. Experiments were performed consisting of a perceptual task in which subjects were asked to set independently their apparent vertical and horizontal plane. The visual background provided no other stimuli to serve as optical direction cues. The task was performed in a number of different body tilt positions with pitches and rolls varied in steps of 30 degs. The results clearly show the distortion of orthogonality of the perceptual space for nonupright body positions. Large interindividual differences were found. Deviations from orthogonality up to 25 deg were detected in the pitch as well as in the roll direction. Implications of this nonorthogonality on further studies of spatial perception and on the construction of virtual environments for human interaction is also discussed.

  15. Incorporating Watson's perceptual model into patchwork watermarking for digital images

    Microsoft Academic Search

    Roland Hu; Fei Chen; Huimin Yu

    2010-01-01

    This paper presents a modified patchwork watermarking scheme for digital images by incorporating the Watson's perceptual model into the watermarking process. Watermarking occurs in the DCT domain. Watson's perceptual model provides a measure of distortions that each DCT coefficient can resist based on the human visual system (HVS). Perceptual information is incorporated into the watermarking scheme by minimizing the Watson's

  16. Perceptual Similarity Metrics for Retrieval of Natural Textures

    E-print Network

    Pappas, Thrasyvoulos N.

    Perceptual Similarity Metrics for Retrieval of Natural Textures Jana Zujovic #1 , Thrasyvoulos N perceptual similarity metrics for the content-based retrieval of natural textures. The goal is to find perceptually similar textures that may have significant differences on a point-by-point basis. The evaluation

  17. Does conceptual implicit memory develop? The role of processing demands.

    PubMed

    Barry, Elaine S

    2007-03-01

    The author investigated the importance of processing considerations within implicit memory in a developmental design. Second-graders (n = 87) and college students (n = 81) completed perceptual (word stem completion) and conceptual (category generation) implicit memory tests after studying target items either nonsemantically (read) or semantically (generated). In support of previous research, the author found no age differences in priming in the nonsemantic study/perceptual test condition. Age differences in priming were found in the semantic study/conceptual test condition, however, where college students had significantly higher priming scores than did children. These developmental dissociations support the theory that the processing requirements of conceptual implicit memory are similar to those in explicit memory. The author also discusses the contribution of the Transfer Appropriate Processing (TAP; H. L. Roediger, D. A. Gallo, & L. Geraci, 2002) framework to understanding these findings. PMID:17879509

  18. High speed local area networks

    Microsoft Academic Search

    H. Hodara; E. Miles

    1992-01-01

    Radical changes are taking place in the computer architecture landscape. The big mainframes are being replaced by networks of microcomputers distributed over a wide geographical area. Increases in the speed and memory of computers has created a need for a communication medium capable of transmitting data at a rate exceeding gigabits per second. The low loss, low dispersion optical fiber

  19. Processing determinants of reading speed

    Microsoft Academic Search

    Mark D. Jackson; James L. McClelland

    1979-01-01

    Tested 2 groups of undergraduates (24 Ss) differing in reading ability on a number of reaction-time (RT) tasks designed to determine the speed of encoding visual information at several levels. Ss were given tests of sensory functions, verbal and quantitative reasoning ability, short-term auditory memory span, and ability to comprehend spoken text. The groups did not differ on the sensory

  20. THE DEPENDENCE OF VISUAL SCANNING PERFORMANCE ON SACCADE, FIXATION, AND PERCEPTUAL METRICS

    PubMed Central

    Phillips, Matthew H.; Edelman, Jay A.

    2009-01-01

    We sought to understand the basis of performance variability and perceptual learning in saccadic visual search. Four subjects searched for a target based on its shape in a linear array of densely packed, regularly spaced items, a configuration used to simplify the analysis of performance and to minimize search strategy variability. We measured the dependence of performance—search speed—on the oculomotor variables of fixation duration and saccade amplitude, both within and across experimental sessions. We also measured perceptual span, the area in visual space in which subjects could identify the target above chance, with a modified version of the task using a gaze-contingent display with transiently appearing targets. The principal finding of this study was that both within and across sessions, saccade metrics accounted for much more of the variability and improvement in performance than did fixation duration. Increases in search speed were due primarily to the processing information from a greater area of the visual field, rather than processing information from a fixed area more quickly, though there was a small but consistent decrease in fixation duration across sessions. The increase in performance derived from an increase in perceptual span and not merely an increase in subjects’ efficiency in ‘tiling’ the search array with regions of visibility. PMID:18295297

  1. Image Data Compression Having Minimum Perceptual Error

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B. (Inventor)

    1997-01-01

    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.

  2. Image data compression having minimum perceptual error

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B. (inventor)

    1995-01-01

    A method for performing image compression that eliminates redundant and invisible image components is described. 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 present invention adapts or customizes the quantization matrix to the image being compressed. The quantization matrix comprises visual masking by luminance and contrast techniques and by an error pooling technique all resulting in a minimum perceptual error for any given bit rate, or minimum bit rate for a given perceptual error.

  3. Does Perceptual-Motor Calibration Generalize across Two Different Forms of Locomotion? Investigations of Walking and Wheelchairs

    PubMed Central

    Kunz, Benjamin R.; Creem-Regehr, Sarah H.; Thompson, William B.

    2013-01-01

    The relationship between biomechanical action and perception of self-motion during walking is typically consistent and well-learned but also adaptable. This perceptual-motor coupling can be recalibrated by creating a mismatch between the visual information for self-motion and walking speed. Perceptual-motor recalibration of locomotion has been demonstrated through effects on subsequent walking without vision, showing that learned perceptual-motor coupling influences a dynamic representation of one's spatial position during walking. Our present studies test whether recalibration of wheelchair locomotion, a novel form of locomotion for typically walking individuals, similarly influences subsequent wheelchair locomotion. Furthermore, we test whether adaptation to the pairing of visual information for self-motion during one form of locomotion transfers to a different locomotion modality. We find strong effects of perceptual-motor recalibration for matched locomotion modalities – walking/walking and wheeling/wheeling. Transfer across incongruent locomotion modalities showed weak recalibration effects. The results have implications both for theories of perceptual-motor calibration mechanisms and their effects on spatial orientation, as well as for practical applications in training and rehabilitation. PMID:23424615

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

    PubMed

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

    2013-08-01

    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

  5. Journal of Experimental Psychology: Learning, Memory,and Cognition

    E-print Network

    Palmeri, Thomas

    Journal of Experimental Psychology: Learning, Memory,and Cognition 1997,Vol.23, No. 2, 324. A new theory, the exemplar-based random walk (EBRW) model, was used to explain the results. Combining within a competitive random walk decision process. People often make perceptual and conceptual judgments

  6. Intersensory Redundancy Enhances Memory in Bobwhite Quail Embryos

    ERIC Educational Resources Information Center

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

    2004-01-01

    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.…

  7. Working Memory Enhances Visual Perception: Evidence from Signal Detection Analysis

    ERIC Educational Resources Information Center

    Soto, David; Wriglesworth, Alice; Bahrami-Balani, Alex; Humphreys, Glyn W.

    2010-01-01

    We show that perceptual sensitivity to visual stimuli can be modulated by matches between the contents of working memory (WM) and stimuli in the visual field. Observers were presented with an object cue (to hold in WM or to merely attend) and subsequently had to identify a brief target presented within a colored shape. The cue could be…

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  9. Uncovering Camouflage: Amygdala Activation Predicts Long-Term Memory

    E-print Network

    Rubin, Nava

    Neuron Article Uncovering Camouflage: Amygdala Activation Predicts Long-Term Memory of Induced (``camouflage''), followed by brief exposures to the original images (``solution''), which led to induced as ``remembered'' if detailed perceptual knowledge was elicited from the camouflage image alone. During encoding

  10. False Memories for Suggestions: The Impact of Conceptual Elaboration

    ERIC Educational Resources Information Center

    Zaragoza, Maria S.; Mitchell, Karen J.; Payment, Kristie; Drivdahl, Sarah

    2011-01-01

    Relatively little attention has been paid to the potential role that reflecting on the meaning and implications of suggested events (i.e., conceptual elaboration) might play in promoting the creation of false memories. Two experiments assessed whether encouraging repeated conceptual elaboration, would, like perceptual elaboration, increase false…

  11. Event Boundaries in Perception Affect Memory Encoding and Updating

    ERIC Educational Resources Information Center

    Swallow, Khena M.; Zacks, Jeffrey M.; Abrams, Richard A.

    2009-01-01

    Memory for naturalistic events over short delays is important for visual scene processing, reading comprehension, and social interaction. The research presented here examined relations between how an ongoing activity is perceptually segmented into events and how those events are remembered a few seconds later. In several studies, participants…

  12. Memory Skills of Deaf Learners: Implications and Applications

    ERIC Educational Resources Information Center

    Hamilton, Harley

    2011-01-01

    This paper will review research on working memory and short-term memory abilities of deaf individuals delineating strengths and weaknesses. The areas of memory reviewed include weaknesses such as sequential recall, processing speed, attention, and memory load. Strengths include free recall, visuospatial recall, imagery and dual encoding.…

  13. An Efficient Buffer Memory System for Subarray Access

    Microsoft Academic Search

    Jong Won Park

    2001-01-01

    Many current graphical display systems utilize a buffer memory system to contain a two-dimensional image array to be modified and displayed. In order to speed up the update of the buffer memory system, it is required that the buffer memory system accesses many image points within an image subarray in parallel. This paper proposes an efficient buffer memory system for

  14. Category and perceptual learning in subjects with treated Wilson's disease.

    PubMed

    Xu, Pengjing; Lu, Zhong-Lin; Wang, Xiaoping; Dosher, Barbara; Zhou, Jiangning; Zhang, Daren; Zhou, Yifeng

    2010-01-01

    To explore the relationship between category and perceptual learning, we examined both category and perceptual learning in patients with treated Wilson's disease (WD), whose basal ganglia, known to be important in category learning, were damaged by the disease. We measured their learning rate and accuracy in rule-based and information-integration category learning, and magnitudes of perceptual learning in a wide range of external noise conditions, and compared the results with those of normal controls. The WD subjects exhibited deficits in both forms of category learning and in perceptual learning in high external noise. However, their perceptual learning in low external noise was relatively spared. There was no significant correlation between the two forms of category learning, nor between perceptual learning in low external noise and either form of category learning. Perceptual learning in high external noise was, however, significantly correlated with information-integration but not with rule-based category learning. The results suggest that there may be a strong link between information-integration category learning and perceptual learning in high external noise. Damage to brain structures that are important for information-integration category learning may lead to poor perceptual learning in high external noise, yet spare perceptual learning in low external noise. Perceptual learning in high and low external noise conditions may involve separate neural substrates. PMID:20224790

  15. Infants Experience Perceptual Narrowing for Nonprimate Faces

    ERIC Educational Resources Information Center

    Simpson, Elizabeth A.; Varga, Krisztina; Frick, Janet E.; Fragaszy, Dorothy

    2011-01-01

    Perceptual narrowing--a phenomenon in which perception is broad from birth, but narrows as a function of experience--has previously been tested with primate faces. In the first 6 months of life, infants can discriminate among individual human and monkey faces. Though the ability to discriminate monkey faces is lost after about 9 months, infants…

  16. Perceptual Learning During Action Video Game Playing

    Microsoft Academic Search

    C. Shawn Green; Renjie Li; Daphne Bavelierb

    2009-01-01

    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

  17. Perceptual Completion in Newborn Human Infants

    ERIC Educational Resources Information Center

    Valenza, Eloisa; Leo, Irene; Gava, Lucia; Simion, Francesca

    2006-01-01

    Despite decades of studies of human infants, a still open question concerns the role of visual experience in the development of the ability to perceive complete shapes over partial occlusion. Previous studies show that newborns fail to manifest this ability, either because they lack the visual experience required for perceptual completion or…

  18. Perceptual Assessment of Demosaicing Algorithm Performance

    E-print Network

    Salvaggio, Carl

    Perceptual Assessment of Demosaicing Algorithm Performance PHILIPPE LONGÈRE, XUEMEI ZHANG, PETER B the most preferred images. Detailed examination of the data, however, indicated that the good performance and in part by Agilent Technologies, Inc. P. Longère was with the Psychology Department, University of Cali

  19. Intelligent Perceptual Shaping of a Digital Watermark

    E-print Network

    Fernandez, Thomas

    Amir Khan and Imran Usman. I appreciate the help of Mr. Mohajir shah, Abdul latif, Fayaz Khan, Abduli Intelligent Perceptual Shaping of a Digital Watermark by Asifullah Khan (May 2006) A thesis submitted for the degree of Doctor of Philosophy to the Ghulam Ishaq Khan Institute of Engineering Sciences

  20. Perceptual Load Influences Selective Attention across Development

    ERIC Educational Resources Information Center

    Couperus, Jane W.

    2011-01-01

    Research suggests that visual selective attention develops across childhood. However, there is relatively little understanding of the neurological changes that accompany this development, particularly in the context of adult theories of selective attention, such as N. Lavie's (1995) perceptual load theory of attention. This study examined visual…

  1. Perceptual issues in augmented reality revisited

    Microsoft Academic Search

    Ernst Kruijff; J. Edward Swan; Steven Feiner

    2010-01-01

    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

  2. Perceptual dimensions for a dynamic tactile display

    NASA Astrophysics Data System (ADS)

    Pappas, Thrasyvoulos N.; Tartter, Vivien C.; Seward, Andrew G.; Genzer, Boris; Gourgey, Karen; Kretzschmar, Ilona

    2009-02-01

    We propose a new approach for converting graphical and pictorial information into tactile patterns that can be displayed in a static or dynamic tactile device. The key components of the proposed approach are (1) an algorithm that segments a scene into perceptually uniform segments; (2) a procedure for generating perceptually distinct tactile patterns; and (3) a mapping of the visual textures of the segments into tactile textures that convey similar concepts. We used existing digital halftoning and other techniques to generate a wide variety of tactile textures. We then conducted formal and informal subjective tests with sighted (but visually blocked) and visually-impaired subjects to determine the ability of human tactile perception to perceive differences among them. In addition to generating perceptually distinguishable tactile patterns, our goal is to identify significant dimensions of tactile texture perception, which will make it possible to map different visual attributes into independent tactile attributes. Our experimental results indicate that it is poosible to generate a number of perceptually distinguishable tactile patterns, and that different dimensions of tactile texture perception can indeed be identified.

  3. Unsupervised perceptual model for color image's segmentation

    Microsoft Academic Search

    P. Sobrevilla; D. Gomez; J. Montero; E. Montseny

    2005-01-01

    Color segmentation is a fundamental step in image understanding. Moreover, for getting accurate color image's segmentation algorithms human being's perception of color should be considered. In this line we propose an unsupervised segmentation algorithm that is based on a fuzzy graph coloring process for representing the fuzzy color similarity degrees among neighboring pixels from a perceptual point of view. As

  4. Perceptual and Neural Olfactory Similarity in Honeybees

    E-print Network

    Menzel, Randolf - Institut für Biologie

    Perceptual and Neural Olfactory Similarity in Honeybees Fernando Guerrieri[ , Marco Schubert unanswered. To address this question, we studied olfaction in honeybees Apis mellifera using the olfactory was asymmetric; (iv) a putative olfactory space could be defined for the honeybee with functional group

  5. Physical Anhedonia, Perceptual Aberration, and Psychosis Proneness

    Microsoft Academic Search

    Loren J. Chapman; William S. Edell; Jean P. Chapman

    1980-01-01

    Two groups of hypothetically psychosisprone subjects were chosen from among college students who scored deviantly high on scales of Physical Anhedonia (n = 50) or Perceptual Aberration (n = 65). Scores on these two scales had a small negative correlation, indicating that the scales identify different sets of deviant subjects. These experimental subjects and a control group (n = 66)

  6. A no-reference perceptual blur metric

    Microsoft Academic Search

    Pina Marziliano; Frédéric Dufaux; Stefan Winkler; Touradj Ebrahimi

    2002-01-01

    In this paper, we present a no-reference blur metric for im- ages and video. The blur metric is based on the analysis of the spread of the edges in an image. Its perceptual sig- nificance is validated through subjective experiments. The novel metric is near real-time, has low computational com- plexity and is shown to perform well over a range

  7. Perceptual Quality Assesment for Video Watermarking

    Microsoft Academic Search

    Stefan Winkler; Elisa Drelie Gelasca; Touradj Ebrahimi

    2002-01-01

    Abstract The reliable evaluation of the performance,of watermarking,algorithms is difcult. An important aspect in this process is the assessment of the visibility of the watermark. In this paper, we address this issue and propose a methodology for evaluating the visual quality of watermarked video. Using a software tool that measures different types of perceptual video artifacts, we determine the most

  8. Perceptual quality assessment for video watermarking

    Microsoft Academic Search

    Stefan Winkler; Elisa Drelie Gelasca; Touradj Ebrahimi

    2002-01-01

    The reliable evaluation of the performance of watermarking algorithms is difficult. An important aspect in this process is the assessment of the visibility of the watermark. We address this issue and propose a methodology for evaluating the visual quality of watermarked video. Using a software tool that measures different types of perceptual video artifacts, we determine the most relevant impairments

  9. Contemporary Theories of Perceptual-Motor Development.

    ERIC Educational Resources Information Center

    Nelson, Monte; Pyfer, Jean L.

    Contemporary theories of perceptual-motor development and dysfunction are analyzed in detail in this review of the literature. Studies focused on observation of delays, deviations, cause, theories of development, and programs of remediation. It is suggested that it may be presumptuous for theorists to delineate three, four, or ten characteristics…

  10. Adaptive Criterion Setting in Perceptual Decision Making

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  11. Late Maturation of Auditory Perceptual Learning

    ERIC Educational Resources Information Center

    Huyck, Julia Jones; Wright, Beverly A.

    2011-01-01

    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…

  12. Knowledge Representation and Reasoning for Perceptual Anchoring

    Microsoft Academic Search

    Jonas Melchert; Silvia Coradeschi; Amy Loutfi

    2007-01-01

    In this work we report results on the use of symbolic knowledge representation and reasoning (KRR) for percep- tual anchoring. This is the creation and maintenance of a connection between symbolic and perceptual description that refer to the same physical object in the environment. We extend an anchoring framework to manage the symbolic information in a KRR system, and to

  13. Perceptual Simulation in Developing Language Comprehension

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  14. Perceptual Scale Space and its Applications

    Microsoft Academic Search

    Yizhou Wang; Siavosh Bahrami; Song-Chun Zhu

    2005-01-01

    In this paper, we study a perceptual scale space by con- structing a so-called sketch pyramid which augments the Gaussian and Laplacian pyramid representations in tradi- tional image scale space theory. Each level of this sketch pyramid is a generic attributed graph - called the primal sketch which is inferred from the corresponding image at the same level of the

  15. Memory Matters

    MedlinePLUS

    ... different parts. Some of them are important for memory. The hippocampus (say: hih-puh-KAM-pus) is one of the more important parts of the brain that processes memories. Old information and new information, or memories, are ...

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

    PubMed

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

    2011-07-01

    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

  17. The dimensionality of perceptual category learning: a state-trace analysis.

    PubMed

    Newell, Ben R; Dunn, John C; Kalish, Michael

    2010-07-01

    State-trace analysis was used to investigate the effect of concurrent working memory load on perceptual category learning. Initial reanalysis of Zeithamova and Maddox (2006, Experiment 1) revealed an apparently two-dimensional state-trace plot consistent with a dual-system interpretation of category learning. However, three modified replications of the original experiment found evidence of a single resource underlying the learning of both rule-based and information integration category structures. Follow-up analyses of the Zeithamova and Maddox data, restricted to only those participants who had learned the category task and performed the concurrent working memory task adequately, revealed a one-dimensional plot consistent with a single-resource interpretation and the results of the three new experiments. The results highlight the potential of state-trace analysis in furthering our understanding of the mechanisms underlying category learning. PMID:20551337

  18. Memory Palaces

    ERIC Educational Resources Information Center

    Wood, Marianne

    2007-01-01

    This article presents a lesson called Memory Palaces. A memory palace is a memory tool used to remember information, usually as visual images, in a sequence that is logical to the person remembering it. In his book, "In the Palaces of Memory", George Johnson calls them "...structure(s) for arranging knowledge. Lots of connections to language arts,…

  19. Places and faces: Geographic environment influences the ingroup memory advantage.

    PubMed

    Rule, Nicholas O; Garrett, James V; Ambady, Nalini

    2010-03-01

    The preferential allocation of attention and memory to the ingroup (the ingroup memory advantage) is one of the most replicated effects in the psychological literature. But little is known about what factors may influence such effects. Here the authors investigated a potential influence: category salience as determined by the perceiver's geographic environment. They did so by studying the ingroup memory advantage in perceptually ambiguous groups for whom perceptual cues do not make group membership immediately salient. Individuals in an environment in which a particular group membership was salient (Mormon and non-Mormon men and women living in Salt Lake City, Utah) showed better memory for faces belonging to their ingroup in an incidental encoding paradigm. Majority group participants in an environment where this group membership was not salient (non-Mormon men and women in the northeastern United States), however, showed no ingroup memory advantage whereas minority group participants (Mormons) in the same environment did. But in the same environment, when differences in group membership were made accessible via an unobtrusive priming task, non-Mormons did show an ingroup memory advantage and Mormons' memory for ingroup members increased. Environmental context cues therefore influence the ingroup memory advantage for categories that are not intrinsically salient. PMID:20175617

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

    PubMed Central

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

    2015-01-01

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

  1. Atypicalities in perceptual adaptation in autism do not extend to perceptual causality.

    PubMed

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

    2015-01-01

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

  2. Drawing from Memory: Hand-Eye Coordination at Multiple Scales

    PubMed Central

    Spivey, Michael J.

    2013-01-01

    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

  3. Perceptual spaces: mathematical structures to neural mechanisms.

    PubMed

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

    2013-11-01

    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

  4. Perceptual conflict between vision and touch.

    PubMed

    Ogawa, T

    1976-06-01

    Although most of the studies support the conclusion that a perceptual conflict may be resolved in the visual dominance, a few suggest its prematurity and methodological problems. In the present study, the conflict was made by the instruction and the trick in order to keep the S's naivety, and the degree of conflict was varied. wthe visual comparison (vision), the haptic comparison (touch), the visual-haptic comparison (drawing by a pencil), and the haptic-visual comparison (production by the plasticine) were used as the comparison procedures. The result was that the perceptual conflict was resolved in a compromise between vision and touch. However, as the degree of conflict became greater, the judgements in the conflict tended to depend upon the comparison procedures. And in such a conflict taht the visual size was smaller than the tactual, the vision dominance tended to occur, and vice versa. PMID:988361

  5. A perceptual metric for photo retouching

    PubMed Central

    Kee, Eric; Farid, Hany

    2011-01-01

    In recent years, advertisers and magazine editors have been widely criticized for taking digital photo retouching to an extreme. Impossibly thin, tall, and wrinkle- and blemish-free models are routinely splashed onto billboards, advertisements, and magazine covers. The ubiquity of these unrealistic and highly idealized images has been linked to eating disorders and body image dissatisfaction in men, women, and children. In response, several countries have considered legislating the labeling of retouched photos. We describe a quantitative and perceptually meaningful metric of photo retouching. Photographs are rated on the degree to which they have been digitally altered by explicitly modeling and estimating geometric and photometric changes. This metric correlates well with perceptual judgments of photo retouching and can be used to objectively judge by how much a retouched photo has strayed from reality. PMID:22123980

  6. From Perceptual Categories to Concepts: What Develops?

    PubMed Central

    Sloutsky, Vladimir M.

    2010-01-01

    People are remarkably smart: they use language, possess complex motor skills, make non-trivial inferences, develop and use scientific theories, make laws, and adapt to complex dynamic environments. Much of this knowledge requires concepts and this paper focuses on how people acquire concepts. It is argued that conceptual development progresses from simple perceptual grouping to highly abstract scientific concepts. This proposal of conceptual development has four parts. First, it is argued that categories in the world have different structure. Second, there might be different learning systems (sub-served by different brain mechanisms) that evolved to learn categories of differing structures. Third, these systems exhibit differential maturational course, which affects how categories of different structures are learned in the course of development. And finally, an interaction of these components may result in the developmental transition from perceptual groupings to more abstract concepts. This paper reviews a large body of empirical evidence supporting this proposal. PMID:21116483

  7. Affecting speed and accuracy in perception.

    PubMed

    Bocanegra, Bruno R

    2014-12-01

    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

  8. Perceptual Issues in Stereoscopic Signal Processing

    Microsoft Academic Search

    Scott J. Daly; Robert T. Held; David M. Hoffman

    2011-01-01

    Perceiving three-dimensional video imagery appro- priately in a display requires matching parameters throughout the imaging pathway, such as inter-aperture distance at the stereoscopic camera side with parallax shifting at the display side. In addition, many tradeoffs and compromises are often made at different points in the imaging pathway, leading to common perceptual distortions. Some of these may be simple two-dimen-

  9. Perceptual Centering Effects in Body Orientation

    Microsoft Academic Search

    D. A. Hanes

    2006-01-01

    This study mathematically characterizes the results of DiZio and Lackner (Percept Psychphys 39(1): 39–46) on the perception\\u000a of self-orientation during circular vection induced by an optokinetic stimulus. Using the hypothesis of perceptual centering,\\u000a it is shown that five basic centering transformations can logically account for the full range of illusions reported by the\\u000a subjects. All five of these transformations center

  10. Sequential priming of 3-D perceptual organization

    Microsoft Academic Search

    Jason S. McCarley; Zijiang J. He

    2001-01-01

    In four experiments, the effects of sequential priming on the perceptual organization of complex three-dimensional (3-D) displays\\u000a were examined. Observers were asked to view stereoscopic arrays and to search an embedded subset of items for an odd-colored\\u000a target while 3-D orientation of the stimuli was varied randomly between trials. Search times decreased reliably when 3-D stimulus\\u000a orientation was unchanged on

  11. The Effect of Set Size on the Relation Between Saccadic and Perceptual Decisions During Search

    NASA Technical Reports Server (NTRS)

    Eckstein, M. P.; Beutter, B. R.; Stone, L. S.; Wenzel, Beth (Technical Monitor)

    1998-01-01

    We have shown that when searching for a disk in noise at one of 10 locations, the accuracy of the I st saccade is similar to that of the perceptual decision at the time of saccadic programming. The present study has two goals: 1) to test whether this linden - extends to a contrast-discrimination task without noise, and 2) to measure the effect of set size on the relation between saccadic and perceptual decisions. Methods: Three observers searched over a grey background (34.5 cd/sq m) for a bright disk (63.2 cd/sq m) among dim disks (54.1 cd/sq m) along the circumference of a circle (r = 5.9 deg.) centered on a fixation cress. Four set sizes (2, 4, 6, 12) were used. In the 1st condition, stimuli were presented for 1 sec. and observers used natural eye movements. We then measured the accuracy of the first saccade (% correct using a shortest-distance criterion). In the 2nd condition, observers fixated a central cross at all times and the stimulus duration was approx. 70 as less than the median latency of the first saccade in the 1st condition (saccadic programming time). We then recorded perceptual performance and discarded trials in which observers broke fixation. Results: For set sizes of 2, 4, 8, and 12, the mean d' across observers for the perceptual decision was 2.03, 1.96, 1.94, 1.71, respectively, while the mean d' of the first saccade was only 0.73, 1.40, 1.23, 1.17. Conclusions: Unlike detection of a disk in noise, for all observers and set-sizes, the perceptual accuracy at the time of saccadic programming is better than that of the lst saccade. For set-sizes of 4, 6, and 12, the amount of information available to the perceptual system relative to that available to the saccadic system is approximately constant (fixed do ratio). For these higher set sizes, the constancy in do across set size for both perception and saccadic decisions is consistent with a simple signal detection theory (SDT) model that processes noisy signals in parallel. However, for 2 observers, at a set-size of 2, saccadic targeting appears to be worse than the SDT model prediction, perhaps due to speed-accuracy trade-off.

  12. Perceptual Consequences of “Hidden” Hearing Loss

    PubMed Central

    Barker, Daphne; Prendergast, Garreth

    2014-01-01

    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

  13. Self-stimulatory behavior and perceptual reinforcement.

    PubMed Central

    Lovaas, I; Newsom, C; Hickman, C

    1987-01-01

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

  14. Domain-specific development of face memory but not face perception.

    PubMed

    Weigelt, Sarah; Koldewyn, Kami; Dilks, Daniel D; Balas, Benjamin; McKone, Elinor; Kanwisher, Nancy

    2014-01-01

    How does the remarkable human ability for face recognition arise over development? Competing theories have proposed either late maturity (beyond 10 years) or early maturity (before 5 years), but have not distinguished between perceptual and memory aspects of face recognition. Here, we demonstrate a perception-memory dissociation. We compare rate of development for (adult, human) faces versus other social stimuli (bodies), other discrete objects (cars), and other categories processed in discrete brain regions (scenes, bodies), from 5 years to adulthood. For perceptual discrimination, performance improved with age at the same rate for faces and all other categories, indicating no domain-specific development. In contrast, face memory increased more strongly than non-face memory, indicating domain-specific development. The results imply that each theory is partly true: the late maturity theory holds for face memory, and the early maturity theory for face perception. PMID:24118764

  15. Memory for details with self-referencing.

    PubMed

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

    2011-11-01

    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

  16. Using reconfigurable hardware to customize memory hierarchies

    NASA Astrophysics Data System (ADS)

    Zhong, Peixin; Martonosi, Margaret

    1996-10-01

    Over the past decade or more, processor speeds have increased much more quickly than memory speeds. As a result, a large, and still increasing, processor-memory performance gap has formed. Many significant applications suffer from substantial memory bottlenecks, and their memory performance problems are often either too unusual or extreme to be mitigated by cache memories along. Such specialized performance 'bugs' require specialized solutions, but it is impossible to provide case-by-case memory hierarchies or caching strategies on general-purpose computers. We have investigated the potential of implementing mechanisms like victim caches and prefetch buffers in reconfigurable hardware to improve application memory behavior. Based on technology and commercial trends, our simulation-based studies use a forward-looking model in which configurable logic is located on the CPU chip. Given such assumptions, our results show that the flexibility of being able to specialize configurable hardware to an application's memory referencing behavior more than balances the slightly slower response times of configurable memory hierarchy structures. For our three applications, small, specialized memory hierarchy additions such as victim caches and prefetch buffers can reduce miss rates substantially and can drop total execution times for these programs to between 60 and 80% of their original execution times. Our results also indicate that different memory specializations may be most effective for each application; this highlights the usefulness of configurable memory hierarchies that are specialized on a per-application basis.

  17. Perceptual study of the impact of varying frame rate on motion imagery interpretability

    NASA Astrophysics Data System (ADS)

    Fenimore, Charles; Irvine, John; Cannon, David; Roberts, John; Aviles, Ivelisse; Isreal, Steven; Brennan, Michelle; Simon, Larry; Miller, James; Haverkamp, Donna; Tighe, Paul F.; Gross, Michael

    2006-02-01

    The development of a motion imagery (MI) quality scale, akin to the National Image Interpretibility Rating Scale (NIIRS) for still imagery, would have great value to designers and users of surveillance and other MI systems. A multiphase study has adopted a perceptual approach to identifying the main MI attributes that affect interpretibility. The current perceptual study measured frame rate effects for simple motion imagery interpretation tasks of detecting and identifying a known target. By using synthetic imagery, there was full control of the contrast and speed of moving objects, motion complexity, the number of confusers, and the noise structure. To explore the detectibility threshold, the contrast between the darker moving objects and the background was set at 5%, 2%, and 1%. Nine viewers were to detect or identify a moving synthetic "bug" in each of 288 10-second clip. We found that frame rate, contrast, and confusers had a statistically significant effect on image interpretibility (at the 95% level), while the speed and background showed no significant effect. Generally, there was a significant loss in correct detection and identification for frame rates below 10 F/s. Increasing the contrast improved detection and at high contrast, confusers did not affect detection. Confusers reduced detection of higher speed objects. Higher speed improved detection, but complicated identification, although this effect was small. Higher speed made detection harder at 1 Frame/s, but improved detection at 30 F/s. The low loss of quality at moderately lower frame rates may have implications for bandwidth limited systems. A study is underway to confirm, with live action imagery, the results reported here with synthetic.

  18. Permalloy film NDRO memory

    Microsoft Academic Search

    F. Janisch

    1965-01-01

    A thin magnetic film NDRO storage cell has been developed for very high-speed word-organized memories. The storage cell contains two 500-Å, 15-mil-square Permalloy film elements with a read and sense line between them. One film element is deposited on a metallic ground plane, so that the read line and its image in the ground plane are coupled to the readout

  19. Can language-action links explain language laterality?: an ERP study of perceptual and articulatory learning of novel pseudowords.

    PubMed

    Pulvermüller, Friedemann; Kiff, James; Shtyrov, Yury

    2012-07-01

    We here investigate whether the well-known laterality of spoken language to the dominant left hemisphere could be explained by the learning of sensorimotor links between a word's articulatory program and its corresponding sound structure. Human-specific asymmetry of acoustic-articulatory connectivity is evident structurally, at the neuroanatomical level, in the arcuate fascicle, which connects superior-temporal and frontal cortices and is more developed in the left hemisphere. Because these left-lateralised fronto-temporal fibres provide a substrate for auditory-motor associations, we hypothesised that learning of acoustic-articulatory coincidences produces laterality, whereas perceptual learning does not. Twenty subjects studied a large (n=48) set of novel meaningless syllable combinations, pseudowords, in a perceptual learning condition, where they carefully listened to repeatedly presented novel items, and, crucially, in an articulatory learning condition, where each item had to be repeated immediately, so that articulatory and auditory speech-evoked cortical activations coincided. In the 14 subjects who successfully passed the learning routine and could recognize the learnt items reliably, both perceptual and articulatory learning were found to lead to an increase of pseudoword-elicited event-related potentials (ERPs), thus reflecting the formation of new memory circuits. Importantly, after articulatory learning, pseudoword-elicited ERPs were more strongly left-lateralised than after perceptual learning. Source localisation confirmed that perceptual learning led to increased activation in superior-temporal cortex bilaterally, whereas items learnt in the articulatory condition activated bilateral superior-temporal auditory in combination with left-pre-central motor areas. These results support a new explanation of the laterality of spoken language based on the neuroanatomy of sensorimotor links and Hebbian learning principles. PMID:21440252

  20. Evidence accumulation in obsessive-compulsive disorder: the role of uncertainty and monetary reward on perceptual decision-making thresholds.

    PubMed

    Banca, Paula; Vestergaard, Martin D; Rankov, Vladan; Baek, Kwangyeol; Mitchell, Simon; Lapa, Tatyana; Castelo-Branco, Miguel; Voon, Valerie

    2015-04-01

    The compulsive behaviour underlying obsessive-compulsive disorder (OCD) may be related to abnormalities in decision-making. The inability to commit to ultimate decisions, for example, patients unable to decide whether their hands are sufficiently clean, may reflect failures in accumulating sufficient evidence before a decision. Here we investigate the process of evidence accumulation in OCD in perceptual discrimination, hypothesizing enhanced evidence accumulation relative to healthy volunteers. Twenty-eight OCD patients and thirty-five controls were tested with a low-level visual perceptual task (random-dot-motion task, RDMT) and two response conflict control tasks. Regression analysis across different motion coherence levels and Hierarchical Drift Diffusion Modelling (HDDM) were used to characterize response strategies between groups in the RDMT. Patients required more evidence under high uncertainty perceptual contexts, as indexed by longer response time and higher decision boundaries. HDDM, which defines a decision when accumulated noisy evidence reaches a decision boundary, further showed slower drift rate towards the decision boundary reflecting poorer quality of evidence entering the decision process in patients under low uncertainty. With monetary incentives emphasizing speed and penalty for slower responses, patients decreased the decision thresholds relative to controls, accumulating less evidence in low uncertainty. These findings were unrelated to visual perceptual deficits and response conflict. This study provides evidence for impaired decision-formation processes in OCD, with a differential influence of high and low uncertainty contexts on evidence accumulation (decision threshold) and on the quality of evidence gathered (drift rates). It further emphasizes that OCD patients are sensitive to monetary incentives heightening speed in the speed-accuracy tradeoff, improving evidence accumulation. PMID:25425323

  1. Ongoing behavior predicts perceptual report of interval duration

    PubMed Central

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

    2014-01-01

    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

  2. Low-Power SRAM and ROM Memories

    Microsoft Academic Search

    Jean-Marc Masgonty; Stefan Cserveny; Christian Piguet

    Memories are a main concern in low-power and high-speed designs. In a processor based SoC (System on Chip), they limit most of the time the speed and are the main part of the power consumption. For SRAM memories in 0.25?m, several improved low-power techniques have been applied, such as divided word lines at word level, physically split bitlines and a

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

    ERIC Educational Resources Information Center

    Ratcliff, Roger; Smith, Philip L.

    2010-01-01

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

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

    PubMed

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

    2008-12-24

    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

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

    PubMed

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

    2014-01-01

    Category learning facilitates perception along relevant stimulus dimensions, even when tested in a discrimination task that does not require categorization. While this general phenomenon has been demonstrated previously, perceptual facilitation along dimensions has been documented by measuring different specific phenomena in different studies using different kinds of objects. Across several object domains, there is support for acquired distinctiveness, the stretching of a perceptual dimension relevant to learned categories. Studies using faces and studies using simple separable visual dimensions have also found evidence of acquired equivalence, the shrinking of a perceptual dimension irrelevant to learned categories, and categorical perception, the local stretching across the category boundary. These later two effects are rarely observed with complex non-face objects. Failures to find these effects with complex non-face objects may have been because the dimensions tested previously were perceptually integrated. Here we tested effects of category learning with non-face objects categorized along dimensions that have been found to be processed by different areas of the brain, shape and motion. While we replicated acquired distinctiveness, we found no evidence for acquired equivalence or categorical perception. PMID:25520691

  6. Perceptual learning in clear displays optimizes perceptual expertise: Learning the limiting process

    PubMed Central

    Dosher, Barbara Anne; Lu, Zhong-Lin

    2005-01-01

    Human operators develop expertise in perceptual tasks by practice or perceptual learning. For noisy displays, practice improves performance by learned external-noise filtering. For clear displays, practice improves performance by improved amplification or enhancement of the stimulus. Can these two mechanisms of perceptual improvement be trained separately? In an orientation task, we found that training with clear displays generalized to performance in noisy displays, but we did not find the reverse to be true. In noisy displays, the noise in the stimulus limits performance. In clear displays, performance is limited by noisiness of internal representations and processes. Our results suggest that training in one display condition optimizes the limiting factor(s) in performance in that condition and that noise filtering is also improved by exposure to the stimulus in clear displays. The asymmetric pattern of transfer implies the existence of two independent mechanisms of perceptual learning, which may reflect channel reweighting in adult visual system. These results also suggest that training operators with clear stimuli may suffice to improve performance in a range of clear and noisy environments by simultaneous learning by two mechanisms. PMID:15795377

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

    PubMed Central

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

    2012-01-01

    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

  8. Computing Speed

    NSDL National Science Digital Library

    2011-01-01

    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.

  9. A perceptual image quality evaluation based on local spatial information

    E-print Network

    Paris-Sud XI, Université de

    A perceptual image quality evaluation based on local spatial information N. Girard1 , E. Baudrier2 This paper presents a new comparative objective method for image quality evaluation. This method relies on two keys points: a local objective evaluation and a perceptual gathering. The local evaluation

  10. Perceptual Organization of Visual Structure Requires a Flexible Learning Mechanism

    ERIC Educational Resources Information Center

    Aslin, Richard N.

    2011-01-01

    Bhatt and Quinn (2011) provide a compelling and comprehensive review of empirical evidence that supports the operation of principles of perceptual organization in young infants. They also have provided a comprehensive list of experiences that could serve to trigger the learning of at least some of these principles of perceptual organization, and…

  11. Pupil-linked arousal determines variability in perceptual decision making

    E-print Network

    Nieuwenhuis, Sander

    1 Pupil-linked arousal determines variability in perceptual decision making Peter R. Murphy1) ­ 527 3874 E: p.murphy@fsw.leidenuniv.nl #12;2 Abstract Decision making between several alternatives determinant of variability in perceptual decision making. We measured pupil size, a highly sensitive index

  12. Subjective perceptual methods for comparing backpacks in the field

    Microsoft Academic Search

    SJ Legg; A Barr; DI Hedderley

    2003-01-01

    Subjective perceptual methods have provided useful information in the laboratory about small differences in backpack design when physiological and biomechanical comparisons are ineffective, but have never been used in the field. This study therefore evaluated, in a controlled field trial with 10 male participants, the suitability of quantitative and qualitative subjective perceptual approaches to distinguish between subtle design differences in

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    Six-month-olds reliably discriminate different monkey and human faces whereas 9-month-olds only discriminate different human faces. It is often falsely assumed that perceptual narrowing reflects a permanent change in perceptual abilities. In 3 experiments, ninety-six 12-month-olds' discrimination of unfamiliar monkey faces was examined. Following…

  14. Learning perceptual skills: behavioral probes into adult cortical plasticity

    Microsoft Academic Search

    Avi Karni; Giuseppe Bertini

    1997-01-01

    Recent studies of the improvement of perceptual performance as a function of training — perceptual learning — have provided new insights into the neuronal substrates of this type of skill learning in the adult brain. Issues such as where in the brain, when and under what conditions practice-related changes occur are under investigation. The results of these studies suggest that

  15. Harnessing the Wandering Mind: The Role of Perceptual Load

    ERIC Educational Resources Information Center

    Forster, Sophie; Lavie, Nilli

    2009-01-01

    Perceptual load is a key determinant of distraction by task-irrelevant stimuli (e.g., Lavie, N. (2005). "Distracted and confused?: Selective attention under load." "Trends in Cognitive Sciences," 9, 75-82). Here we establish the role of perceptual load in determining an internal form of distraction by task-unrelated thoughts (TUTs or…

  16. Perceptually lossless wavelet-based compression for medical images

    Microsoft Academic Search

    Nai-Wen Lin; Tsaifa Yu; Andrew K. Chan

    1997-01-01

    In this paper, we present a wavelet-based medical image compression scheme so that images displayed on different devices are perceptually lossless. Since visual sensitivity of human varies with different subbands, we apply the perceptual lossless criteria to quantize the wavelet transform coefficients of each subband such that visual distortions are reduced to unnoticeable. Following this, we use a high compression

  17. Error-resilient Perceptual Haptic Data Communication based on

    E-print Network

    Steinbach, Eckehard

    coding for haptic signals based on Differential Pulse Code Modulation (DPCM) and Adaptive DifferentialError-resilient Perceptual Haptic Data Communication based on Probabilistic Receiver State,fernanda.brandi,florian.schweiger,eckehard.steinbach}@tum.de Abstract. We present an error-resilient perceptual haptic data com- pression scheme based

  18. Multisensory Cues Capture Spatial Attention Regardless of Perceptual Load

    ERIC Educational Resources Information Center

    Santangelo, Valerio; Spence, Charles

    2007-01-01

    We compared the ability of auditory, visual, and audiovisual (bimodal) exogenous cues to capture visuo-spatial attention under conditions of no load versus high perceptual load. Participants had to discriminate the elevation (up vs. down) of visual targets preceded by either unimodal or bimodal cues under conditions of high perceptual load (in…

  19. The Role of Perceptual Load in Object Recognition

    ERIC Educational Resources Information Center

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

    2009-01-01

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

  20. Perceptual load as a necessary condition for selective attention

    Microsoft Academic Search

    Nilli Lavie

    1995-01-01

    The early and late selection debate may be resolved if perceptual load of relevant information determines the selective processing of irrelevant information. This hypothesis was tested in 3 studies; all used a variation of the response competition paradigm to measure irrelevant processing when load in the relevant processing was varied. Perceptual load was manipulated by relevant display set size or

  1. The Role of Perceptual Load in Inattentional Blindness

    ERIC Educational Resources Information Center

    Cartwright-Finch, Ula; Lavie, Nilli

    2007-01-01

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

  2. Active and Passive Perceptual Learning in the Visually Impaired.

    ERIC Educational Resources Information Center

    Conrod, Beverley E.; And Others

    1986-01-01

    Active and passive perceptual training methods were tested with 30 macular degeneration patients to improve their residual vision. The main conclusion was that perceptual training may contribute to successful visual adjustment and that the effect of training is not limited to a particular level of visual impairment. (Author/CL)

  3. Motoric Aids to Perceptual Training. The Slow Learner Series.

    ERIC Educational Resources Information Center

    Chaney, Clara M.; Kephart, Newell C.

    Written from a developmental viewpoint, this book for parents and teachers presents both a theoretical orientation and perceptual motor activities for training children with learning disabilities, both the brain injured and the retarded. The theoretical basis for training generalized motor responses is considered in terms of motor perceptual

  4. Perceptual Specificity Effects in Rereading: Evidence from Eye Movements

    ERIC Educational Resources Information Center

    Sheridan, Heather; Reingold, Eyal M.

    2012-01-01

    The present experiments examined perceptual specificity effects using a rereading paradigm. Eye movements were monitored while participants read the same target word twice, in two different low-constraint sentence frames. The congruency of perceptual processing was manipulated by either presenting the target word in the same distortion typography…

  5. Neurological Evidence Linguistic Processes Precede Perceptual Simulation in Conceptual Processing

    PubMed Central

    Louwerse, Max; Hutchinson, Sterling

    2012-01-01

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

  6. A Scanner Darkly: Protecting User Privacy From Perceptual Applications

    E-print Network

    Shmatikov, Vitaly

    , third-party perceptual ap- plication is running on a trusted device. DARKLY is integrated with OpenCV unmodified or with very few modifications and minimal performance overheads vs. native OpenCV. In most cases's perceptual sensors via special-purpose software libraries. DARKLY is integrated with OpenCV, a popular

  7. Chinese and English Infants' Tone Perception: Evidence for Perceptual Reorganization

    Microsoft Academic Search

    Karen Mattock; Denis Burnham

    2006-01-01

    Over half the world's population speaks a tone language, yet infant speech perception research has typically focused on consonants and vowels. Very young infants can dis- criminate a wide range of native and nonnative consonants and vowels, and then in a process of perceptual reorganization over the 1st year, discrimination of most nonna- tive speech sounds deteriorates. We investigated perceptual

  8. Neurological evidence linguistic processes precede perceptual simulation in conceptual processing.

    PubMed

    Louwerse, Max; Hutchinson, Sterling

    2012-01-01

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

  9. Perceptual Modality and Musical Aptitude among Kindergarten Students.

    ERIC Educational Resources Information Center

    Sanders, Paul D.

    1996-01-01

    Examines the relationship between perceptual modality measured by the Swassing-Barbe Modality Index (SBMI) to musical aptitude measured by Primary Measures of Music Audiation (PMMA) in kindergarten students. Reports correlations between the measures that support findings at other grade levels. Supports the theory that perceptual modalities become…

  10. Effects of Perceptual-Motor Programs on Children.

    ERIC Educational Resources Information Center

    Thomas, Jerry R.

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

  11. An Ecological Perceptual Aid for Precision Vertical Landings

    E-print Network

    Cummings, Mary "Missy"

    An Ecological Perceptual Aid for Precision Vertical Landings by Cristin Anne Smith B and Astronautics in partial fulfillment of the requirements for the degree of Master of Science in Aeronautics by . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Jaime Peraire Chairman, Department Committee on Graduate Students #12;2 #12;An Ecological Perceptual Aid

  12. The Perceptual Domain: A Taxonomy for Allied Health Educators.

    ERIC Educational Resources Information Center

    Hooker, Ellen Z.

    1981-01-01

    A modified version of the perceptual taxonomy applicable to allied health education is presented. Methods concerning application of the taxonomy are suggested. Use of the taxonomy of the perceptual domain is recommended to help allied health educators plan instruction and evaluate teaching. (CT)

  13. Which Working Memory Functions Predict Intelligence?

    ERIC Educational Resources Information Center

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

    2008-01-01

    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…

  14. System-Level Integration of Mass Memory

    NASA Technical Reports Server (NTRS)

    Cox, Brian; Mellstrom, Jeffrey; Wysocky, Terry

    2008-01-01

    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.

  15. Multiple Peak Resonant Tunneling Diode for Multi-Valued Memory

    Microsoft Academic Search

    Sen-Jung Wei; Hung Chang Lin

    1991-01-01

    Several designs for a high-speed static random access multivalued memory using the folding characteristics of multiple peak resonant tunneling diodes (RTDs) are presented. The different designs are described and studied by comparing their power consumption under different conditions of device parameters and the switching speed. It is shown that the proposed memory cell using a pair of multiple-peak RTDs yields

  16. Memory systems

    Microsoft Academic Search

    Larry R. Squire; Donald Chai

    1998-01-01

    Two recent findings are summarized here that bear on the organization of memory and brain systems. First, the capacity for simple recognition of familiarity (a form of declarative memory) depends on the hippocampal region in both humans and nonhuman primates. Second, probabilistic classification learning (a form of nondeclarative memory akin to habit learning) depends on the caudate nucleus and putamen.

  17. Perceptual-components architecture for digital video

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B.

    1990-01-01

    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.

  18. Perceptual user interface in virtual shopping environment

    NASA Astrophysics Data System (ADS)

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

    2003-04-01

    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.

  19. The nature of impairments of memory in patients with end-stage renal disease (ESRD).

    PubMed

    Jones, Daniel J W; Harris, John P; Vaux, Emma; Hadid, Rebecca; Kean, Rebecca; Butler, Laurie T

    2015-08-01

    Possible impairments of memory in end-stage renal disease (ESRD) were investigated in two experiments. In Experiment 1, in which stimulus words were presented visually, participants were tested on conceptual or perceptual memory tasks, with retrieval being either explicit or implicit. Compared with healthy controls, ESRD patients were impaired when memory required conceptual but not when it required perceptual processing, regardless of whether retrieval was explicit or implicit. An impairment of conceptual implicit memory (priming) in the ESRD group represented a previously unreported deficit compared to healthy aging. There were no significant differences between pre- and immediate post-dialysis memory performance in ESRD patients on any of the tasks. In Experiment 2, in which presentation was auditory, patients again performed worse than controls on an explicit conceptual memory task. We conclude that the type of processing required by the task (conceptual vs. perceptual) is more important than the type of retrieval (explicit vs. implicit) in memory failures in ESRD patients, perhaps because temporal brain regions are more susceptible to the effects of the illness than are posterior regions. PMID:25980628

  20. 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

    Ramponi, Cristina; Barnard, Philip J.; Kherif, Ferath; Henson, Richard N.

    2011-01-01

    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…

  1. Nanoporous silicon oxide memory.

    PubMed

    Wang, Gunuk; Yang, Yang; Lee, Jae-Hwang; Abramova, Vera; Fei, Huilong; Ruan, Gedeng; Thomas, Edwin L; Tour, James M

    2014-08-13

    Oxide-based two-terminal resistive random access memory (RRAM) is considered one of the most promising candidates for next-generation nonvolatile memory. We introduce here a new RRAM memory structure employing a nanoporous (NP) silicon oxide (SiOx) material which enables unipolar switching through its internal vertical nanogap. Through the control of the stochastic filament formation at low voltage, the NP SiOx memory exhibited an extremely low electroforming voltage (? 1.6 V) and outstanding performance metrics. These include multibit storage ability (up to 9-bits), a high ON-OFF ratio (up to 10(7) A), a long high-temperature lifetime (? 10(4) s at 100 °C), excellent cycling endurance (? 10(5)), sub-50 ns switching speeds, and low power consumption (? 6 × 10(-5) W/bit). Also provided is the room temperature processability for versatile fabrication without any compliance current being needed during electroforming or switching operations. Taken together, these metrics in NP SiOx RRAM provide a route toward easily accessed nonvolatile memory applications. PMID:24992278

  2. Memory Skills of Deaf Learners: Implications and Applications

    ERIC Educational Resources Information Center

    Hamilton, Harley

    2011-01-01

    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.…

  3. Is Statistical Learning Constrained by Lower Level Perceptual Organization?

    PubMed Central

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

    2013-01-01

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

  4. Recovered memories.

    PubMed

    Loftus, Elizabeth F; Davis, Deborah

    2006-01-01

    The issues surrounding repressed, recovered, or false memories have sparked one of the greatest controversies in the mental health profession in the twentieth century. We review evidence concerning the existence of the repression and recovery of autobiographical memories of traumatic events and research on the development of false autobiographical memories, how specific therapeutic procedures can lead to false memories, and individual vulnerability to resisting false memories. These findings have implications for therapeutic practice, for forensic practice, for research and training in psychology, and for public policy. PMID:17716079

  5. Memory protection

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1988-01-01

    Accidental overwriting of files or of memory regions belonging to other programs, browsing of personal files by superusers, Trojan horses, and viruses are examples of breakdowns in workstations and personal computers that would be significantly reduced by memory protection. Memory protection is the capability of an operating system and supporting hardware to delimit segments of memory, to control whether segments can be read from or written into, and to confine accesses of a program to its segments alone. The absence of memory protection in many operating systems today is the result of a bias toward a narrow definition of performance as maximum instruction-execution rate. A broader definition, including the time to get the job done, makes clear that cost of recovery from memory interference errors reduces expected performance. The mechanisms of memory protection are well understood, powerful, efficient, and elegant. They add to performance in the broad sense without reducing instruction execution rate.

  6. A no-reference perceptual blurriness metric based fast super-resolution of still pictures using sparse representation

    NASA Astrophysics Data System (ADS)

    Choi, Jae-Seok; Bae, Sung-Ho; Kim, Munchurl

    2015-03-01

    In recent years, perceptually-driven super-resolution (SR) methods have been proposed to lower computational complexity. Furthermore, sparse representation based super-resolution is known to produce competitive high-resolution images with lower computational costs compared to other SR methods. Nevertheless, super-resolution is still difficult to be implemented with substantially low processing power for real-time applications. In order to speed up the processing time of SR, much effort has been made with efficient methods, which selectively incorporate elaborate computation algorithms for perceptually sensitive image regions based on a metric, such as just noticeable distortion (JND). Inspired by the previous works, we first propose a novel fast super-resolution method with sparse representation, which incorporates a no-reference just noticeable blur (JNB) metric. That is, the proposed fast super-resolution method efficiently generates super-resolution images by selectively applying a sparse representation method for perceptually sensitive image areas which are detected based on the JNB metric. Experimental results show that our JNB-based fast super-resolution method is about 4 times faster than a non-perceptual sparse representation based SR method for 256× 256 test LR images. Compared to a JND-based SR method, the proposed fast JNB-based SR method is about 3 times faster, with approximately 0.1 dB higher PSNR and a slightly higher SSIM value in average. This indicates that our proposed perceptual JNB-based SR method generates high-quality SR images with much lower computational costs, opening a new possibility for real-time hardware implementations.

  7. Perceptual learning: Toward a comprehensive theory

    PubMed Central

    Watanabe, Takeo; Sasaki, Yuka

    2014-01-01

    Visual perceptual learning (VPL) is long-term performance increase resulting from visual perceptual experience. Task-relevant VPL of a feature results from training of a task on the feature relevant to the task. Task-irrelevant VPL arises as a result of exposure to the feature irrelevant to the trained task. There are at least two serious problems. First, which stage of information processing is changed in association with task-relevant VPL is controversial. Second, no model has ever explained both task-relevant and task-irrelevant VPL. Here we propose a dual plasticity model, in which there are feature-based plasticity that is a change in a representation of the learned feature and task-based plasticity that is a change in processing of the trained task. While the two types of plasticity underlie task-relevant VPL, only feature-based plasticity lies under task-irrelevant VPL. This model provides a new comprehensive framework in which apparently contradictory results could be explained. PMID:25251494

  8. Referenceless perceptual fog density prediction model

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

    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.

  9. Attentional control of early perceptual learning.

    PubMed Central

    Ahissar, M; Hochstein, S

    1993-01-01

    The performance of adult humans in simple visual tasks improves dramatically with practice. This improvement is highly specific to basic attributes of the trained stimulus, suggesting that the underlying changes occur at low-level processing stages in the brain, where different orientations and spatial frequencies are handled by separate channels. We asked whether these practice effects are determined solely by activity in stimulus-driven mechanisms or whether high-level attentional mechanisms, which are linked to the perceptual task, might control the learning process. We found that practicing one task did not improve performance in an alternative task, even though both tasks used exactly the same visual stimuli but depended on different stimulus attributes (either orientation of local elements or global shape). Moreover, even when the experiment was designed so that the same responses were associated with the same stimuli (although subjects were instructed to attend to the attribute underlying one task), learning did not transfer from one task to the other. These results suggest that specific high-level attentional mechanisms, controlling changes at early visual processing levels, are essential in perceptual learning. Images Fig. 3 PMID:8516322

  10. Overview of emerging nonvolatile memory technologies.

    PubMed

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

    2014-01-01

    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

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

    PubMed Central

    Wilkinson, Krista M.; McIlvane, William J.

    2013-01-01

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

  12. Perceptual load, voluntary attention, and aging: An event-related potential study , Shimin Fu b

    E-print Network

    Parasuraman, Raja

    Perceptual load, voluntary attention, and aging: An event-related potential study Yan Wang Aging Perceptual load Voluntary attention The locus of attentional selection is known to vary with perceptual load (Lavie et al., 2004). Under voluntary attention, perceptual load modulates selective visual

  13. Perceptual organization in computer vision: a review and a proposal for a classificatory structure

    Microsoft Academic Search

    Sudeep Sarkar; Kim L. Boyer

    1993-01-01

    The role of perceptual organization in computer vision systems is explored. This is done from four vantage points. A brief history of perceptual organization research in both humans and computer vision is offered. A classificatory structure in which to cast perceptual organization research to clarify both the nomenclature and the relationships among the many contributions is proposed. The perceptual organization

  14. Neural Mechanisms by Which Attention Modulates the Comparison of Remembered and Perceptual Representations

    PubMed Central

    Kuo, Bo-Cheng; Astle, Duncan E.

    2014-01-01

    Attention is important for effectively comparing incoming perceptual information with the contents of visual short-term memory (VSTM), such that any differences can be detected. However, how attentional mechanisms operate upon these comparison processes remains largely unknown. Here we investigate the underlying neural mechanisms by which attention modulates the comparisons between VSTM and perceptual representations using functional magnetic resonance imaging (fMRI). Participants performed a cued change detection task. Spatial cues were presented to orient their attention either to the location of an item in VSTM prior to its comparison (retro-cues), or simultaneously (simultaneous-cues) with the probe array. A no-cue condition was also included. When attention cannot be effectively deployed in advance (i.e. following the simultaneous-cues), we observed a distributed and extensive activation pattern in the prefrontal and parietal cortices in support of successful change detection. This was not the case when participants can deploy their attention in advance (i.e. following the retro-cues). The region-of-interest analyses confirmed that neural responses for successful change detection versus correct rejection in the visual and parietal regions were significantly different for simultaneous-cues compared to retro-cues. Importantly, we found enhanced functional connectivity between prefrontal and parietal cortices when detecting changes on the simultaneous-cue trials. Moreover, we demonstrated a close relationship between this functional connectivity and d? scores. Together, our findings elucidate the attentional and neural mechanisms by which items held in VSTM are compared with incoming perceptual information. PMID:24466193

  15. Holographic random access memory (HRAM)

    Microsoft Academic Search

    ERNEST CHUANG; Wenhai Liu; JEAN-JACQUES P. DROLET; DEMETRI PSALTIS

    1999-01-01

    We examine the present state of holographic random access memory (HRAM) systems and address the primary challenges that face this technology, specifically size, speed, and cost. We show that a fast HRAM system can be implemented with a compact architecture by incorporating conjugate readout, a smart-pixel array, and a linear array of laser diodes. Preliminary experimental results support the feasibility

  16. Attention, short-term memory, and action selection: A unifying theory

    Microsoft Academic Search

    Gustavo Deco; Edmund T. Rolls

    2005-01-01

    Cognitive behaviour requires complex context-dependent processing of information that emerges from the links between attentional perceptual processes, working memory and reward-based evaluation of the performed actions. We describe a computational neuroscience theoretical framework which shows how an attentional state held in a short term memory in the prefrontal cortex can by top-down processing influence ventral and dorsal stream cortical areas

  17. Corresponding delay-dependent biases in spatial language and spatial memory

    Microsoft Academic Search

    John Lipinski; John P. Spencer; Larissa K. Samuelson

    2010-01-01

    The present study addresses the relationship between linguistic and non-linguistic spatial representations. In three experiments\\u000a we probe spatial language and spatial memory at the same time points in the task sequence. Experiments 1 and 2 show analogous\\u000a delay-dependent biases in spatial language and spatial memory. Experiment 3 extends this correspondence, showing that additional\\u000a perceptual structure along the vertical axis reduces

  18. When Spatial and Temporal Contiguities Help the Integration in Working Memory: "A Multimedia Learning" Approach

    ERIC Educational Resources Information Center

    Mammarella, Nicola; Fairfield, Beth; Di Domenico, Alberto

    2013-01-01

    Two experiments examined the effects of spatial and temporal contiguities in a working memory binding task that required participants to remember coloured objects. In Experiment 1, a black and white drawing and a corresponding phrase that indicated its colour perceptually were either near or far (spatial study condition), while in Experiment 2,…

  19. The neural correlates of correctly rejecting lures during memory retrieval: the role of item relatedness.

    PubMed

    Bowman, Caitlin R; Dennis, Nancy A

    2015-06-01

    Successful memory retrieval is predicated not only on recognizing old information, but also on correctly rejecting new information (lures) in order to avoid false memories. Correctly rejecting lures is more difficult when they are perceptually or semantically related to information presented at study as compared to when lures are distinct from previously studied information. This behavioral difference suggests that the cognitive and neural basis of correct rejections differs with respect to the relatedness between lures and studied items. The present study sought to identify neural activity that aids in suppressing false memories by examining the network of brain regions underlying correct rejection of related and unrelated lures. Results showed neural overlap in the right hippocampus and anterior parahippocampal gyrus associated with both related and unrelated correct rejections, indicating that some neural regions support correctly rejecting lures regardless of their semantic/perceptual characteristics. Direct comparisons between related and unrelated correct rejections showed that unrelated correct rejections were associated with greater activity in bilateral middle and inferior temporal cortices, regions that have been associated with categorical processing and semantic labels. Related correct rejections showed greater activation in visual and lateral prefrontal cortices, which have been associated with perceptual processing and retrieval monitoring. Thus, while related and unrelated correct rejections show some common neural correlates, related correct rejections are driven by greater perceptual processing whereas unrelated correct rejections show greater reliance on salient categorical cues to support quick and accurate memory decisions. PMID:25862563

  20. Stepping into a Map: Initial Heading Direction Influences Spatial Memory Flexibility

    ERIC Educational Resources Information Center

    Gagnon, Stephanie A.; Brunyé, Tad T.; Gardony, Aaron; Noordzij, Matthijs L.; Mahoney, Caroline R.; Taylor, Holly A.

    2014-01-01

    Learning a novel environment involves integrating first-person perceptual and motoric experiences with developing knowledge about the overall structure of the surroundings. The present experiments provide insights into the parallel development of these egocentric and allocentric memories by intentionally conflicting body- and world-centered frames…

  1. Adapting to Changing Memory Retrieval Demands: Evidence from Event-Related Potentials

    ERIC Educational Resources Information Center

    Benoit, Roland G.; Werkle-Bergner, Markus; Mecklinger, Axel; Kray, Jutta

    2009-01-01

    This study investigated preparatory processes involved in adapting to changing episodic memory retrieval demands. Event-related potentials (ERPs) were recorded while participants performed a general old/new recognition task and a specific task that also required retrieval of perceptual details. The relevant task remained either constant or changed…

  2. Selective Interference on the Holistic Processing of Faces in Working Memory

    ERIC Educational Resources Information Center

    Cheung, Olivia S.; Gauthier, Isabel

    2010-01-01

    Faces and objects of expertise compete for early perceptual processes and holistic processing resources (Gauthier, Curran, Curby, & Collins, 2003). Here, we examined the nature of interference on holistic face processing in working memory by comparing how various types of loads affect selective attention to parts of face composites. In dual tasks,…

  3. Integration of stimulus dimensions in perception and memory: Composition rules and psychophysical relations

    Microsoft Academic Search

    Daniel Algom; Yuval Wolf; Bina Bergman

    1985-01-01

    A series of five experiments used the method of magnitude estimation to assess how height and width are integrated in perceptual and in memorial judgments of area. Separate groups of subjects estimated the areas of perceived or remembered rectangles produced by a symmetrical 4 × 4 factorial design of height and width. Additional independent groups of observers made area judgments,

  4. Perceptual and contextual awareness: methodological considerations in the search for the neural correlates of consciousness

    PubMed Central

    Navajas, Joaquin; Rey, Hernan G.; Quian Quiroga, Rodrigo

    2014-01-01

    In the last decades, the neural correlates of consciousness (NCCs) have been explored using both invasive and non-invasive recordings by comparing the brain activity elicited by seen versus unseen visual stimuli (i.e., the contrastive analysis). Here, we review a selection of these studies and discuss a set of considerations to improve the search for the NCCs using the contrastive analysis. In particular, we first argue in favor of implementing paradigms where different perceptual outputs are obtained using identical visual inputs. Second, we propose that the large disagreement in the field -in terms of the dissimilar neural patterns proposed as NCCs- is partially explained by the fact that different studies report the neural correlates of different conscious processes in the brain. More specifically, we distinguish between the perceptual awareness of a visual stimulus, associated to a boost in object-selective neural assemblies, and a more elaborate process (contextual awareness) that we argue is reflected in the firing of concept neurons in the medial temporal lobe, triggering a rich representation of the context, associations, and memories linked to the specific stimulus. PMID:25221537

  5. Missing the Memory Wall: The Case for Processor\\/Memory Integration

    Microsoft Academic Search

    Ashley Saulsbury; Fong Pong; Andreas Nowatzyk

    1996-01-01

    Current high performance computer systems use complex, large superscalar CPUs that interface to the main memory through a hierarchy of caches and interconnect systems. These CPU-centric designs invest a lot of power and chip area to bridge the widening gap between CPU and main memory speeds. Yet, many large applications do not operate well on these systems and are limited

  6. Intact mirror-tracing and impaired rotary-pursuit skill learning in patients with Huntington's disease: Evidence for dissociable memory systems in skill learning

    Microsoft Academic Search

    John D. E. Gabrieli; Glenn T. Stebbins; Jaswinder Singh; Daniel B. Willingham

    1997-01-01

    Skill learning in early-stage Huntington's disease (HD) patients was compared with that of normal controls on 2 perceptual-motor tasks, rotary pursuit and mirror tracing. HD patients demonstrated a dissociation between impaired rotary-pursuit and intact mirror-tracing skill learning. These results suggest that different forms of perceptual-mo tor skill learning are mediated by separable neural circuits. A striatal memory system may be

  7. Abnormality of semantic network in patients with Alzheimer's disease. Evidence from verbal, perceptual, and olfactory domains.

    PubMed

    Chan, A; Salmon, D; Nordin, S; Murphy, C; Razani, J

    1998-11-30

    A series of studies was initiated to model the organization of semantic memory in Alzheimer's disease (AD) patients using multidimensional scaling (MDS) and Pathfinder analyses. The resulting models (cognitive maps or semantic networks) embed studied stimuli in a coordinate space or network where distances between points are assumed to reflect psychological proximity between items. The organization of semantic networks in verbal and sensory domains were modeled based upon the frequency of the subject's choice of two concepts as most alike. Results suggested that while the organization of concepts in the semantic networks of AD patients was primarily based upon a concrete perceptual dimension in both verbal and olfactory domains, those of normal controls subjects were predominantly organized by an abstract conceptual attribute. Also, networks of AD patients were more complex and chaotic than normal, that is, they consisted of more unnecessary connections and of atypical strengths of association between concepts. PMID:9929671

  8. The Psychologist Said Quickly, “Dialogue Descriptions Modulate Reading Speed!”

    PubMed Central

    Stites, Mallory C.; Luke, Steven G.; Christianson, Kiel

    2012-01-01

    The current study investigates whether the semantic content of a dialogue description can affect reading times on an embedded quote to determine if the speed at which a character is described as saying a quote influences how quickly it is read. Yao and Scheepers (2011) previously found that readers were faster to read direct quotes when the preceding context implied that the talker generally spoke quickly, an effect attributed to perceptual simulation of talker speed. The current study manipulated the speed of a physical action performed by the speaker independently from character talking rate to determine if these sources have separable effects on perceptual simulation of a direct quote. Results showed that readers spent less time reading direct quotes described as being said quickly compared to slowly (e.g., John walked/bolted into the room and said energetically/nonchalantly, “I finally found my car keys”), an effect that was not present when a nearly identical phrase was presented as an indirect quote (e.g., John…said energetically that he finally found his car keys). The speed of the character’s movement did not affect direct quote reading times. Furthermore, fast adverbs were themselves read significantly faster than slow adverbs, an effect we attribute to implicit effects on the eye movement program stemming from automatically activated semantic features of the adverbs. Our findings add to the literature on perceptual simulation by showing that these effects can be instantiated with only a single adverb, and are strong enough to override effects of global sentence speed. PMID:22927027

  9. Perceptual Learning Improves Stereoacuity in Amblyopia

    PubMed Central

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

    2014-01-01

    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

  10. Factors Affecting Perceptual Thresholds in Epiretinal Prostheses

    PubMed Central

    de Balthasar, Chloé; Patel, Sweta; Roy, Arup; Freda, Ricardo; Greenwald, Scott; Horsager, Alan; Mahadevappa, Manjunatha; Yanai, Douglas; McMahon, Matthew J.; Humayun, Mark S.; Greenberg, Robert J.; Weiland, James D.; Fine, Ione

    2008-01-01

    Purpose The goal was to evaluate how perceptual thresholds are related to electrode impedance, electrode size, the distance of electrodes from the retinal surface, and retinal thickness in six subjects blind as a result of retinitis pigmentosa, who received epiretinal prostheses implanted monocularly as part of a U.S. Food and Drug Administration (FDA)–approved clinical trial. Methods The implant consisted of an extraocular unit containing electronics for wireless data, power recovery, and generation of stimulus current, and an intraocular unit containing 16 platinum stimulating electrodes (260- or 520-?m diameter) arranged in a 4 × 4 pattern. The electrode array was held onto the retina by a small tack. Stimulation was controlled by a computer-based external system that allowed independent control over each electrode. Perceptual thresholds (the current necessary to see a percept on 79% of trials) and impedance were measured for each electrode on a biweekly basis. The distance of electrodes from the retinal surface and retinal thickness were measured by optical coherence tomography on a less regular basis. Results Stimulation thresholds for detecting phosphenes correlated with the distance of the electrodes from the retinal surface, but not with electrode size, electrode impedance, or retinal thickness. Conclusions Maintaining close proximity between the electrode array and the retinal surface is critical in developing a successful retinal implant. With the development of chronic electrode arrays that are stable and flush on the retinal surface, it is likely that the influence of other factors such as electrode size, retinal degeneration, and subject age will become more apparent. PMID:18515576

  11. Perceptual and motor learning underlies human stick-balancing skill.

    PubMed

    Lee, Kwee-Yum; O'Dwyer, Nicholas; Halaki, Mark; Smith, Richard

    2015-01-01

    We investigated the acquisition of skill in balancing a stick (52 cm, 34 g) on the fingertip in nine participants using three-dimensional motion analysis. After 3.5 h of practice over 6 wk, the participants could more consistently balance the stick for longer durations with greatly reduced magnitude and speed of stick and finger movements. Irrespective of level of skill, the balanced stick behaved like a normal noninverted pendulum oscillating under greater-than-gravity torque with simple harmonic motion about a virtual pivot located at the radius of gyration above the center of mass. The control input parameter was the magnitude ratio between the torque applied on the stick by the participant and the torque due to gravity. The participants utilized only a narrow range of this parameter, which did not change with practice, to rotate the stick like a linear mass-spring system. With increased skill, the stick therefore maintained the same period of oscillation but showed marked reductions in magnitude of both oscillation and horizontal translation. Better balancing was associated with 1) more accurate visual localization of the stick and proprioceptive localization of the finger and 2) reduced cross-coupling errors between finger and stick movements in orthogonal directions; i.e., finger movements in the anteroposterior plane became less coupled with stick tip movements in the mediolateral plane, and vice versa. Development of this fine motor skill therefore depended on perceptual and motor learning to provide improved estimation of sensorimotor state and precision of motor commands to an unchanging internal model of the rotational dynamics. PMID:25298388

  12. Behavioral/Systems/Cognitive Perceptual Criteria in the Human Brain

    E-print Network

    Segraves, Kari A.

    Behavioral/Systems/Cognitive Perceptual Criteria in the Human Brain Corey N. White,1 Jeanette A understanding of the neural correlates of decision flexibility and adjustments of behavioral bias. Introduction- nitive scientists to probe different aspects of cognitive processing, includingperception

  13. Perceptual data mining : bootstrapping visual intelligence from tracking behavior

    E-print Network

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

    2002-01-01

    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 ...

  14. An ecological perceptual aid for precision vertical landings

    E-print Network

    Smith, Cristin Anne

    2006-01-01

    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 ...

  15. Cultural Differences in Perceptual Reorganization in US and Pirahã Adults

    PubMed Central

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

    2014-01-01

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

  16. Acoustic and Perceptual Evaluation of Hypernasality of Mentally Retarded Persons.

    ERIC Educational Resources Information Center

    Hutchinson, John M.; Kline, Lorrie Scott

    1980-01-01

    Results of perceptual and acoustic analyses revealed that 20 Down's syndrome young adults were significantly more hypernasal than were two other groups (20 idiopathic and 20 nonretarded Ss). (Author/CL)

  17. Generalized watermarking attack based on watermark estimation and perceptual remodulation

    E-print Network

    Genève, Université de

    Generalized watermarking attack based on watermark estimation and perceptual remodulation image watermarking has become a popular technique for authentication and copyright protection. For verifying the security and robustness of watermarking algorithms, specific attacks have to be applied

  18. Variance misperception explains illusions of confidence in simple perceptual decisions.

    PubMed

    Zylberberg, Ariel; Roelfsema, Pieter R; Sigman, Mariano

    2014-07-01

    Confidence in a perceptual decision is a judgment about the quality of the sensory evidence. The quality of the evidence depends not only on its strength ('signal') but critically on its reliability ('noise'), but the separate contribution of these quantities to the formation of confidence judgments has not been investigated before in the context of perceptual decisions. We studied subjective confidence reports in a multi-element perceptual task where evidence strength and reliability could be manipulated independently. Our results reveal a confidence paradox: confidence is higher for stimuli of lower reliability that are associated with a lower accuracy. We show that the subjects' overconfidence in trials with unreliable evidence is caused by a reduced sensitivity to stimulus variability. Our results bridge between the investigation of miss-attributions of confidence in behavioral economics and the domain of simple perceptual decisions amenable to neuroscience research. PMID:24951943

  19. A PERCEPTUAL DISTORTION METRIC FOR DIGITAL COLOR IMAGES Stefan Winkler

    E-print Network

    Winkler, Stefan

    A PERCEPTUAL DISTORTION METRIC FOR DIGITAL COLOR IMAGES Stefan Winkler Signal Processing Laboratory Swiss Federal Institute of Technology 1015 Lausanne, Switzerland http://ltswww.epfl.ch/~winkler/ Stefan.Winkler

  20. A Perceptual Distortion Metric for Digital Color Video Stefan Winkler

    E-print Network

    Winkler, Stefan

    A Perceptual Distortion Metric for Digital Color Video Stefan Winkler Signal Processing Laboratory Swiss Federal Institute of Technology 1015 Lausanne, Switzerland http://ltswww.epfl.ch/~winkler/ Stefan.Winkler

  1. Phonetic knowledge, phonotactics and perceptual validation for automatic language identification

    E-print Network

    Boula de Mareüil, Philippe

    Phonetic knowledge, phonotactics and perceptual validation for automatic language identification- tribute to human language identification: among the most important are acoustics, phonetics, phonotactics for automatic LId. Acoustic-phonetic and phonotactic modelling benefit from many decades of research first

  2. Binary Partitioning, Perceptual Grouping, and Restoration with Semidefinite Programming1

    E-print Network

    Schellewald, Christian

    Binary Partitioning, Perceptual Grouping, and Restoration with Semidefinite Programming1 Jens interior-point methods (convex programming) and a randomized hyperplane technique. Apart from a symmetry to unsupervised partitioning, figure- ground discrimination and binary restoration are presented along

  3. Binary Partitioning, Perceptual Grouping, and Restoration with Semidefinite Programming

    E-print Network

    Cremers, Daniel

    Binary Partitioning, Perceptual Grouping, and Restoration with Semidefinite Programming Jens interior-point methods (convex programming) and a randomized hyperplane technique. Apart from a symmetry to unsupervised partitioning, figure-ground discrimination, and binary restoration are presented along

  4. Are recovered memories accurate? 

    E-print Network

    Gerkens, David

    2005-08-29

    Research in our laboratory has demonstrated blocked and recovered memories within the context of a controlled experiment. The comparative memory paradigm allows for comparisons of recovered memories, continuous memories, and false memories...

  5. Consolidating memories.

    PubMed

    McGaugh, James L

    2015-01-01

    Our own experiences, as well as the findings of many studies, suggest that emotionally arousing experiences can create lasting memories. This autobiographical article provides a brief summary of the author's research investigating neurobiological systems responsible for the influence of emotional arousal on the consolidation of lasting memories. The research began with the finding that stimulant drugs enhanced memory in rats when administered shortly after training. Those findings suggested the possibility that endogenous systems activated by arousal might influence neural processes underlying memory consolidation. Subsequent findings that adrenal stress hormones activated by learning experiences enhance memory consolidation provided strong evidence supporting this hypothesis. Other findings suggest that the enhancement is induced by stress hormone activation of the amygdala. The findings also suggest that the basolateral amygdala modulates memory consolidation via its projections to brain regions involved in processing different aspects and forms of memory. This emotional-arousal-activated neurobiological system thus seems to play an important adaptive role in insuring that the strength of our memories will reflect their emotional significance. PMID:25559113

  6. Episodic Memories

    ERIC Educational Resources Information Center

    Conway, Martin A.

    2009-01-01

    An account of episodic memories is developed that focuses on the types of knowledge they represent, their properties, and the functions they might serve. It is proposed that episodic memories consist of "episodic elements," summary records of experience often in the form of visual images, associated to a "conceptual frame" that provides a…

  7. Speed of emotional information processing and emotional intelligence

    Microsoft Academic Search

    Yulia A. Dodonova; Yury S. Dodonov

    2012-01-01

    The present study aimed to investigate the relationship between the speed of emotional information processing and emotional intelligence (EI). To evaluate individual differences in the speed of emotional information processing, a recognition memory task consisted of two subtests similar in design but differing in the emotionality of the stimuli. The first subtest required judgment about whether an emotional facial expression

  8. Retrieval Speed as a Determinant of Adult Reading Comprehension.

    ERIC Educational Resources Information Center

    Haupt, Edward J.; Jacobowitz, Tina

    More than 100 college students enrolled in a reading and study skills course participated in a study designed to show the effects of retrieval speed on adult reading comprehension. A microcomputer version of the Posner task was used to measure memory retrieval speed, and reading and listening comprehension were measured from McCall-Crabbs…

  9. Anger as “seeing red”: Evidence for a perceptual association

    Microsoft Academic Search

    Adam K. Fetterman; Michael D. Robinson; Brian P. Meier

    2012-01-01

    Metaphor representation theory contends that people conceptualise their non-perceptual states (e.g., emotion concepts) in perceptual terms. The present research extends this theory to colour manipulations and discrete emotional representations. Two experiments (N=265) examined whether a red font colour would facilitate anger conceptions, consistent with metaphors referring to anger to “seeing red”. Evidence for an implicit anger-red association was robust and

  10. Practical memory checking with Dr. Memory

    Microsoft Academic Search

    Derek Bruening; Qin Zhao

    2011-01-01

    Memory corruption, reading uninitialized memory, using freed memory, and other memory-related errors are among the most difficult programming bugs to identify and fix due to the delay and non-determinism linking the error to an observable symptom. Dedicated memory checking tools are invaluable for finding these errors. However, such tools are difficult to build, and because they must monitor all memory

  11. Visual search for category sets: Tradeoffs between exploration and memory

    PubMed Central

    Kibbe, Melissa M.; Kowler, Eileen

    2012-01-01

    Limitations of working memory force a reliance on motor exploration to retrieve forgotten features of the visual array. A category search task was devised to study tradeoffs between exploration and memory in the face of significant cognitive and motor demands. The task required search through arrays of hidden, multi-featured objects to find three belonging to the same category. Location contents were revealed briefly by either a: (1) mouseclick, or (2) saccadic eye movement with or without delays between saccade offset and object appearance. As the complexity of the category rule increased, search favored exploration, with more visits and revisits needed to find the set. As motor costs increased (mouseclick search or oculomotor search with delays) search favored reliance on memory. Application of the model of J. Epelboim and P. Suppes (2001) to the revisits produced an estimate of immediate memory span (M) of about 4–6 objects. Variation in estimates of M across category rules suggested that search was also driven by strategies of transforming the category rule into concrete perceptual hypotheses. The results show that tradeoffs between memory and exploration in a cognitively demanding task are determined by continual and effective monitoring of perceptual load, cognitive demand, decision strategies and motor effort. PMID:21421747

  12. A new taxonomy for perceptual filling-in

    PubMed Central

    Weil, Rimona S.; Rees, Geraint

    2011-01-01

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

  13. Perceptual, cognitive, and personality rigidity in Parkinson's disease.

    PubMed

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

    2015-03-01

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

  14. Neurofeedback training of gamma band oscillations improves perceptual processing.

    PubMed

    Salari, Neda; Büchel, Christian; Rose, Michael

    2014-10-01

    In this study, a noninvasive electroencephalography-based neurofeedback method is applied to train volunteers to deliberately increase gamma band oscillations (40 Hz) in the visual cortex. Gamma band oscillations in the visual cortex play a functional role in perceptual processing. In a previous study, we were able to demonstrate that gamma band oscillations prior to stimulus presentation have a significant influence on perceptual processing of visual stimuli. In the present study, we aimed to investigate longer lasting effects of gamma band neurofeedback training on perceptual processing. For this purpose, a feedback group was trained to modulate oscillations in the gamma band, while a control group participated in a task with an identical design setting but without gamma band feedback. Before and after training, both groups participated in a perceptual object detection task and a spatial attention task. Our results clearly revealed that only the feedback group but not the control group exhibited a visual processing advantage and an increase in oscillatory gamma band activity in the pre-stimulus period of the processing of the visual object stimuli after the neurofeedback training. Results of the spatial attention task showed no difference between the groups, which underlines the specific role of gamma band oscillations for perceptual processing. In summary, our results show that modulation of gamma band activity selectively affects perceptual processing and therefore supports the relevant role of gamma band activity for this specific process. Furthermore, our results demonstrate the eligibility of gamma band oscillations as a valuable tool for neurofeedback applications. PMID:24992898

  15. Perceptual learning modules in mathematics: enhancing students' pattern recognition, structure extraction, and fluency.

    PubMed

    Kellman, Philip J; Massey, Christine M; Son, Ji Y

    2010-04-01

    Learning in educational settings emphasizes declarative and procedural knowledge. Studies of expertise, however, point to other crucial components of learning, especially improvements produced by experience in the extraction of information: perceptual learning (PL). We suggest that such improvements characterize both simple sensory and complex cognitive, even symbolic, tasks through common processes of discovery and selection. We apply these ideas in the form of perceptual learning modules (PLMs) to mathematics learning. We tested three PLMs, each emphasizing different aspects of complex task performance, in middle and high school mathematics. In the MultiRep PLM, practice in matching function information across multiple representations improved students' abilities to generate correct graphs and equations from word problems. In the Algebraic Transformations PLM, practice in seeing equation structure across transformations (but not solving equations) led to dramatic improvements in the speed of equation solving. In the Linear Measurement PLM, interactive trials involving extraction of information about units and lengths produced successful transfer to novel measurement problems and fraction problem solving. Taken together, these results suggest (a) that PL techniques have the potential to address crucial, neglected dimensions of learning, including discovery and fluent processing of relations; (b) PL effects apply even to complex tasks that involve symbolic processing; and (c) appropriately designed PL technology can produce rapid and enduring advances in learning. PMID:25163790

  16. Is magnetite a universal memory molecule?

    PubMed

    Størmer, Fredrik C

    2014-11-01

    Human stem cells possess memory, and consequently all living human cells must have a memory system. How memory is stored in cells and organisms is an open question. Magnetite is perhaps the best candidate to be a universal memory molecule. Magnetite may give us a clue, because it is the Earth's most distributed and important magnetic material. It is found in living organisms with no known functions except for involvement in navigation in some organisms. In humans magnetite is found in the brain, heart, liver and spleen. Humans suffer from memory dysfunctions in many cases when iron is out of balance. Anomalous concentrations of magnetite is known to be associated with a neurodegenerative disorder like Alzheimer's disease. Due to the rapid speed and accuracy of our brain, memory and its functions must be governed by quantum mechanics. PMID:25236401

  17. Divide and conquer: How perceptual contrast sensitivity and perceptual learning cooperate in reducing input variation in speech perception.

    PubMed

    Sjerps, Matthias J; Reinisch, Eva

    2015-06-01

    Listeners have to overcome variability of the speech signal that can arise, for example, because of differences in room acoustics, differences in speakers' vocal tract properties, or idiosyncrasies in pronunciation. Two mechanisms that are involved in resolving such variation are perceptually contrastive effects that arise from surrounding acoustic context and lexically guided perceptual learning. Although both processes have been studied in great detail, little attention has been paid to how they operate relative to each other in speech perception. The present study set out to address this issue. The carrier parts of exposure stimuli of a classical perceptual learning experiment were spectrally filtered such that the acoustically ambiguous final fricatives sounded relatively more like the lexically intended sound (Experiment 1) or the alternative (Experiment 2). Perceptual learning was found only in the latter case. The findings show that perceptual contrast effects precede lexically guided perceptual learning, at least in terms of temporal order, and potentially in terms of cognitive processing levels as well. (PsycINFO Database Record PMID:25798784

  18. Implicit Memory in Music and Language

    PubMed Central

    Ettlinger, Marc; Margulis, Elizabeth H.; Wong, Patrick C. M.

    2011-01-01

    Research on music and language in recent decades has focused on their overlapping neurophysiological, perceptual, and cognitive underpinnings, ranging from the mechanism for encoding basic auditory cues to the mechanism for detecting violations in phrase structure. These overlaps have most often been identified in musicians with musical knowledge that was acquired explicitly, through formal training. In this paper, we review independent bodies of work in music and language that suggest an important role for implicitly acquired knowledge, implicit memory, and their associated neural structures in the acquisition of linguistic or musical grammar. These findings motivate potential new work that examines music and language comparatively in the context of the implicit memory system. PMID:21927608

  19. Dynamic interactions between visual working memory and saccade target selection

    PubMed Central

    Schneegans, Sebastian; Spencer, John P.; Schöner, Gregor; Hwang, Seongmin; Hollingworth, Andrew

    2014-01-01

    Recent psychophysical experiments have shown that working memory for visual surface features interacts with saccadic motor planning, even in tasks where the saccade target is unambiguously specified by spatial cues. Specifically, a match between a memorized color and the color of either the designated target or a distractor stimulus influences saccade target selection, saccade amplitudes, and latencies in a systematic fashion. To elucidate these effects, we present a dynamic neural field model in combination with new experimental data. The model captures the neural processes underlying visual perception, working memory, and saccade planning relevant to the psychophysical experiment. It consists of a low-level visual sensory representation that interacts with two separate pathways: a spatial pathway implementing spatial attention and saccade generation, and a surface feature pathway implementing color working memory and feature attention. Due to bidirectional coupling between visual working memory and feature attention in the model, the working memory content can indirectly exert an effect on perceptual processing in the low-level sensory representation. This in turn biases saccadic movement planning in the spatial pathway, allowing the model to quantitatively reproduce the observed interaction effects. The continuous coupling between representations in the model also implies that modulation should be bidirectional, and model simulations provide specific predictions for complementary effects of saccade target selection on visual working memory. These predictions were empirically confirmed in a new experiment: Memory for a sample color was biased toward the color of a task-irrelevant saccade target object, demonstrating the bidirectional coupling between visual working memory and perceptual processing. PMID:25228628

  20. Memory Technologies Vivek Asthana

    E-print Network

    Kumar, M. Jagadesh

    Memory Technologies Vivek Asthana 13th Mar 2013 #12;13-Mar-13 2 Memory Usage (2025) #12;13-Mar-13 3 Outline What is a Memory Current Memory technologies · SRAM · DRAM · Flash Upcoming Memory technologies · MRAM · PCRAM · FeRAM · ... #12;13-Mar-13 4 What is a Memory Memory cell: Binary data storage element

  1. Clinical testing of otolith function: perceptual thresholds and myogenic potentials.

    PubMed

    Agrawal, Yuri; Bremova, Tatiana; Kremmyda, Olympia; Strupp, Michael; MacNeilage, Paul R

    2013-12-01

    Cervical and ocular vestibular-evoked myogenic potential (cVEMP/oVEMP) tests are widely used clinical tests of otolith function. However, VEMP testing may not be the ideal measure of otolith function given the significant inter-individual variability in responses and given that the stimuli used to elicit VEMPs are not physiological. We therefore evaluated linear motion perceptual threshold testing compared with cVEMP and oVEMP testing as measures of saccular and utricular function, respectively. A multi-axis motion platform was used to measure horizontal (along the inter-aural and naso-occipital axes) and vertical motion perceptual thresholds. These findings were compared with the vibration-evoked oVEMP as a measure of utricular function and sound-evoked cVEMP as a measure of saccular function. We also considered how perceptual threshold and cVEMP/oVEMP testing are each associated with Dizziness Handicap Inventory (DHI) scores. We enrolled 33 patients with bilateral vestibulopathy of different severities and 42 controls to have sufficient variability in otolith function. Subjects with abnormal oVEMP amplitudes had significantly higher (poorer) perceptual thresholds in the inter-aural and naso-occipital axes in age-adjusted analyses; no significant associations were observed for vertical perceptual thresholds and cVEMP amplitudes. Both oVEMP amplitudes and naso-occipital axis perceptual thresholds were significantly associated with DHI scores. These data suggest that horizontal perceptual thresholds and oVEMPs may estimate the same underlying physiological construct: utricular function. PMID:24077672

  2. Robust perceptual coding of overcomplete frame expansions

    NASA Astrophysics Data System (ADS)

    Pinilla-Dutoit, Javier; Woolley, Sandra I.

    2001-06-01

    The cortex transform provides a meaningful representation of images in terms of the responses of cortical cells. It is based on experimental results form human vision research. The multiple orientations obtained in the expansion are of interest for image analysis applications. In image coders, quantization can exploit to a large extent psychovisual properties. This transform belongs to a group of overcomplete transforms. This property has not benefitted their use in coding applications. However, the inherent redundancy of overcomplete representation can be exploited to increase the robustness of the code. Multiple description coding of overcomplete expansions has been reported to confer more graceful degradation to partial reconstructions in the event of channel erasures. This paper proposes a coding strategy based on orientation transforms that yield perceptually meaningful coefficients. The coding budget is reduced by sampling and quantization. The remaining redundancy is used to provide robustness. In addition, the descriptions can be organized to allow progressive reconstruction. The tradeoff between quantization strength, perceived quality, redundancy and robustness can be incorporated in the design of the coder.

  3. Perceptual prothesis in native Spanish speakers

    NASA Astrophysics Data System (ADS)

    Theodore, Rachel M.; Schmidt, Anna M.

    2003-04-01

    Previous research suggests a perceptual bias exists for native phonotactics [D. Massaro and M. Cohen, Percept. Psychophys. 34, 338-348 (1983)] such that listeners report nonexistent segments when listening to stimuli that violate native phonotactics [E. Dupoux, K. Kakehi, Y. Hirose, C. Pallier, and J. Mehler, J. Exp. Psychol.: Human Percept. Perform. 25, 1568-1578 (1999)]. This study investigated how native-language experience affects second language processing, focusing on how native Spanish speakers perceive the English clusters /st/, /sp/, and /sk/, which represent phonotactically illegal forms in Spanish. To preserve native phonotactics, Spanish speakers often produce prothetic vowels before English words beginning with /s/ clusters. Is the influence of native phonotactics also present in the perception of illegal clusters? A stimuli continuum ranging from no vowel (e.g., ``sku'') to a full vowel (e.g., ``esku'') before the cluster was used. Four final vowel contexts were used for each cluster, resulting in 12 sCV and 12 VsCV nonword endpoints. English and Spanish listeners were asked to discriminate between pairs differing in vowel duration and to identify the presence or absence of a vowel before the cluster. Results will be discussed in terms of implications for theories of second language speech perception.

  4. Depth image enhancement using perceptual texture priors

    NASA Astrophysics Data System (ADS)

    Bang, Duhyeon; Shim, Hyunjung

    2015-03-01

    A depth camera is widely used in various applications because it provides a depth image of the scene in real time. However, due to the limited power consumption, the depth camera presents severe noises, incapable of providing the high quality 3D data. Although the smoothness prior is often employed to subside the depth noise, it discards the geometric details so to degrade the distance resolution and hinder achieving the realism in 3D contents. In this paper, we propose a perceptual-based depth image enhancement technique that automatically recovers the depth details of various textures, using a statistical framework inspired by human mechanism of perceiving surface details by texture priors. We construct the database composed of the high quality normals. Based on the recent studies in human visual perception (HVP), we select the pattern density as a primary feature to classify textures. Upon the classification results, we match and substitute the noisy input normals with high quality normals in the database. As a result, our method provides the high quality depth image preserving the surface details. We expect that our work is effective to enhance the details of depth image from 3D sensors and to provide a high-fidelity virtual reality experience.

  5. Issues in the measurement of perceptual assimilation

    NASA Astrophysics Data System (ADS)

    Harnsberger, James; Wayland, Ratree

    2001-05-01

    This study examined the effect of methodological variables on the fit between predicted discrimination scores based on identification data and actual discrimination data in cross-language speech perception experiments. Such variables include (1) single versus multiple talkers in discrimination test trials; (2) different discrimination test types (e.g., AX, AXB, oddity); and (3) identification tests in which stimuli are presented individually versus stimuli being presented in the same context as they appear in discrimination tests. The optimal pair of identification and discrimination tests, yielding the best match between predicted and actual discrimination scores, can be used in subsequent studies examining perceptual category structure. These methodological variables were examined by presenting American English speakers with two Hindi contrasts, [b]-[p] and breathy voiced dental-retroflex, both in initial position and in an [i], [a], or [u] context. The stimuli appeared in a range of categorial discrimination and identification tests. Early results examining the third variable listed above demonstrate that identification tests that present stimuli in the same context as they appear in corresponding discrimination test trials correlate more strongly with discrimination scores (r=0.72, p<0.05) than identification tests that present stimuli in isolation (r=0.58, p<0.05).

  6. Memory loss

    MedlinePLUS

    ... be for a short time and then resolve (transient). Or it may not go away, and, depending ... Major surgery or severe illness, including brain surgery Transient global amnesia (sudden, temporary loss of memory) of ...

  7. POW Memory

    NSDL National Science Digital Library

    Science Update

    2004-07-12

    Most people think eyewitness testimony is the best possible evidence against an alleged criminal -- especially when that testimony comes from the victim. But people who survive terrifying situations may actually have surprisingly unreliable memories of who or what caused them.

  8. Up-down Asymmetries in Speed Perception

    NASA Technical Reports Server (NTRS)

    Thompson, Peter; Stone, Leland S.

    1997-01-01

    We compared speed matches for pairs of stimuli that moved in opposite directions (upward and downward). Stimuli were elliptical patches (2 deg horizontally by 1 deg vertically) of horizontal sinusoidal gratings of spatial. frequency 2 cycles/deg. Two sequential 380 msec reveal presentations were compared. One of each pair of gratings (the standard) moved at 4 Hz (2 deg/sec), the other (the test) moved at a rate determined by a simple up-down staircase. The point of subjectively equal speed was calculated from the average of the last eight reversals. The task was to fixate a central point and to determine which one of the pair appeared to move faster. Eight of 10 observers perceived the upward drifting grating as moving faster than a grating moving downward but otherwise identical. on average (N = 10), when the standard moved downward, it was matched by a test moving upward at 94.7+/-1.7(SE)% of the standard speed, and when the standard moved upward it was matched by a test moving downward at 105.1+/-2.3(SE)% of the standard speed. Extending this paradigm over a range of spatial (1.5 to 13.5 c/d) and temporal (1.5 to 13.5 Hz) frequencies, preliminary results (N = 4) suggest that, under the conditions of our experiment, upward matter is seen as faster than downward for speeds greater than approx.1 deg/sec, but the effect appears to reverse at speeds below approx.1 deg/sec with downward motion perceived as faster. Given that an up-down asymmetry has been observed for the optokinetic response, both perceptual and oculomotor contributions to this phenomenon deserve exploration.

  9. Memory Solitaire

    NSDL National Science Digital Library

    2013-01-30

    In this online game, learners practice memory recall. They are shown a collage of pictures for two minutes, then have to write down everything they remember and check how they did. After, they learn a memory-improving method of "tell yourself a story" to help train their brain, and try again. Although this activity is designed to be done online and individually, it can easily be adapted to be done using a printout and in a group setting.

  10. A High-Speed Low-Power Multi-VDD CMOS\\/SIMOX SRAM With LV-TTL Level Input\\/Output Pins—Write\\/Read Assist Techniques for 1-V Operated Memory Cells

    Microsoft Academic Search

    Nobutaro Shibata; Mayumi Watanabe; Hideomi Okiyama

    2010-01-01

    The use of multiple power supplies with different output voltages has a great advantage in that it makes it possible to realize high performance ULSIs with low power dissipation. This paper presents a high-speed low-power SRAM that employs three power supplies (1, 2, and 3.3 V). A 1-V power supply is mainly used in the SRAM core to save standby

  11. Acoustic and perceptual evaluation of Mandarin tone productions before and after perceptual training

    NASA Astrophysics Data System (ADS)

    Wang, Yue; Jongman, Allard; Sereno, Joan A.

    2003-02-01

    Training American listeners to perceive Mandarin tones has been shown to be effective, with trainees' identification improving by 21%. Improvement also generalized to new stimuli and new talkers, and was retained when tested six months after training [Y. Wang et al., J. Acoust. Soc. Am. 106, 3649-3658 (1999)]. The present study investigates whether the tone contrasts gained perceptually transferred to production. Before their perception pretest and after their post-test, the trainees were recorded producing a list of Mandarin words. Their productions were first judged by native Mandarin listeners in an identification task. Identification of trainees' post-test tone productions improved by 18% relative to their pretest productions, indicating significant tone production improvement after perceptual training. Acoustic analyses of the pre- and post-training productions further reveal the nature of the improvement, showing that post-training tone contours approximate native norms to a greater degree than pretraining tone contours. Furthermore, pitch height and pitch contour are not mastered in parallel, with the former being more resistant to improvement than the latter. These results are discussed in terms of the relationship between non-native tone perception and production as well as learning at the suprasegmental level.

  12. Suitable Stimuli to Obtain (No) Gender Differences in the Speed of Cognitive Processes Involved in Mental Rotation

    ERIC Educational Resources Information Center

    Jansen-Osmann, Petra; Heil, Martin

    2007-01-01

    Gender differences in speed of perceptual comparison, of picture-plane mental rotation, and in switching costs between trials that do and do not require mental rotation, were investigated as a function of stimulus material with a total sample size of N=360. Alphanumeric characters, PMA symbols, animal drawings, polygons and 3D cube figures were…

  13. Many simple performance parameters about human memory are not well-understood. One such parameter is how the

    E-print Network

    Byrne, Mike

    . ACT-R/PM (Byrne & Anderson, 1998) provides a set of perceptual-motor extensions to the ACT-R cognitive architecture (Anderson & Lebiere, 1998). Communication between central cognition (the ACT-R production system-motor modules deliver results (e.g. representations of percepts) to ACT-R's declarative memory in the form

  14. Perceptual Biases in Relation to Paranormal and Conspiracy Beliefs.

    PubMed

    van Elk, Michiel

    2015-01-01

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

  15. Perceptual Biases in Relation to Paranormal and Conspiracy Beliefs

    PubMed Central

    van Elk, Michiel

    2015-01-01

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

  16. Bayesian natural selection and the evolution of perceptual systems.

    PubMed Central

    Geisler, Wilson S; Diehl, Randy L

    2002-01-01

    In recent years, there has been much interest in characterizing statistical properties of natural stimuli in order to better understand the design of perceptual systems. A fruitful approach has been to compare the processing of natural stimuli in real perceptual systems with that of ideal observers derived within the framework of Bayesian statistical decision theory. While this form of optimization theory has provided a deeper understanding of the information contained in natural stimuli as well as of the computational principles employed in perceptual systems, it does not directly consider the process of natural selection, which is ultimately responsible for design. Here we propose a formal framework for analysing how the statistics of natural stimuli and the process of natural selection interact to determine the design of perceptual systems. The framework consists of two complementary components. The first is a maximum fitness ideal observer, a standard Bayesian ideal observer with a utility function appropriate for natural selection. The second component is a formal version of natural selection based upon Bayesian statistical decision theory. Maximum fitness ideal observers and Bayesian natural selection are demonstrated in several examples. We suggest that the Bayesian approach is appropriate not only for the study of perceptual systems but also for the study of many other systems in biology. PMID:12028784

  17. Music lessons improve auditory perceptual and cognitive performance in deaf children.

    PubMed

    Rochette, Françoise; Moussard, Aline; Bigand, Emmanuel

    2014-01-01

    Despite advanced technologies in auditory rehabilitation of profound deafness, deaf children often exhibit delayed cognitive and linguistic development and auditory training remains a crucial element of their education. In the present cross-sectional study, we assess whether music would be a relevant tool for deaf children rehabilitation. In normal-hearing children, music lessons have been shown to improve cognitive and linguistic-related abilities, such as phonetic discrimination and reading. We compared auditory perception, auditory cognition, and phonetic discrimination between 14 profoundly deaf children who completed weekly music lessons for a period of 1.5-4?years and 14 deaf children who did not receive musical instruction. Children were assessed on perceptual and cognitive auditory tasks using environmental sounds: discrimination, identification, auditory scene analysis, auditory working memory. Transfer to the linguistic domain was tested with a phonetic discrimination task. Musically trained children showed better performance in auditory scene analysis, auditory working memory and phonetic discrimination tasks, and multiple regressions showed that success on these tasks was at least partly driven by music lessons. We propose that musical education contributes to development of general processes such as auditory attention and perception, which, in turn, facilitate auditory-related cognitive and linguistic processes. PMID:25071518

  18. Inferior frontal gyrus activation predicts individual differences in perceptual learning of cochlear-implant simulations

    PubMed Central

    Eisner, Frank; McGettigan, Carolyn; Faulkner, Andrew; Rosen, Stuart; Scott, Sophie K.

    2010-01-01

    Summary This study investigated the neural plasticity associated with perceptual learning of a cochlear implant (CI) simulation. Normal-hearing listeners were trained with vocoded and spectrally-shifted speech simulating a CI while cortical responses were measured with fMRI. A condition in which the vocoded speech was spectrally inverted provided a control for learnability and adaptation. Behavioral measures showed considerable individual variability both in the ability to learn to understand the degraded speech, and in phonological working memory capacity. Neurally, left-lateralized regions in superior temporal sulcus and inferior frontal gyrus (IFG) were sensitive to the learnability of the simulations, but only the activity in prefrontal cortex correlated with inter-individual variation in intelligibility scores and phonological working memory. A region in left angular gyrus (AG) showed an activation pattern that reflected learning over the course of the experiment, and co-variation of activity in AG and IFG was modulated by the learnability of the stimuli. These results suggest that variation in listeners' ability to adjust to vocoded and spectrally-shifted speech is partly reflected in differences in the recruitment of higher-level language processes in prefrontal cortex, and that this variability may further depend on functional links between the left inferior frontal gyrus and angular gyrus. Differences in the engagement of left inferior prefrontal cortex, and its co-variation with posterior parietal areas, may thus underlie some of the variation in speech perception skills that have been observed in clinical populations of CI users. PMID:20505085

  19. Music Lessons Improve Auditory Perceptual and Cognitive Performance in Deaf Children

    PubMed Central

    Rochette, Françoise; Moussard, Aline; Bigand, Emmanuel

    2014-01-01

    Despite advanced technologies in auditory rehabilitation of profound deafness, deaf children often exhibit delayed cognitive and linguistic development and auditory training remains a crucial element of their education. In the present cross-sectional study, we assess whether music would be a relevant tool for deaf children rehabilitation. In normal-hearing children, music lessons have been shown to improve cognitive and linguistic-related abilities, such as phonetic discrimination and reading. We compared auditory perception, auditory cognition, and phonetic discrimination between 14 profoundly deaf children who completed weekly music lessons for a period of 1.5–4?years and 14 deaf children who did not receive musical instruction. Children were assessed on perceptual and cognitive auditory tasks using environmental sounds: discrimination, identification, auditory scene analysis, auditory working memory. Transfer to the linguistic domain was tested with a phonetic discrimination task. Musically trained children showed better performance in auditory scene analysis, auditory working memory and phonetic discrimination tasks, and multiple regressions showed that success on these tasks was at least partly driven by music lessons. We propose that musical education contributes to development of general processes such as auditory attention and perception, which, in turn, facilitate auditory-related cognitive and linguistic processes. PMID:25071518

  20. Short-term memory-based control of wind energy conversion systems

    Microsoft Academic Search

    Xiao-Yan Mei; Zhao Sun; Bin Li; Zhi Yang; Yong D. Song

    2006-01-01

    Variable speed wind turbine control is essential in extracting maximum electric power out of available wind power. The paper presents a memory-based method for variable speed control of wind energy conversion systems. The fundamental idea behind the method is to use certain memorized information (i.e., current rotor speed tracking error, most recent speed tracking error, and previous control experience) to

  1. Dielectric elastomer memory

    NASA Astrophysics Data System (ADS)

    O'Brien, Benjamin M.; McKay, Thomas G.; Xie, Sheng Q.; Calius, Emilio P.; Anderson, Iain A.

    2011-04-01

    Life shows us that the distribution of intelligence throughout flexible muscular networks is a highly successful solution to a wide range of challenges, for example: human hearts, octopi, or even starfish. Recreating this success in engineered systems requires soft actuator technologies with embedded sensing and intelligence. Dielectric Elastomer Actuator(s) (DEA) are promising due to their large stresses and strains, as well as quiet flexible multimodal operation. Recently dielectric elastomer devices were presented with built in sensor, driver, and logic capability enabled by a new concept called the Dielectric Elastomer Switch(es) (DES). DES use electrode piezoresistivity to control the charge on DEA and enable the distribution of intelligence throughout a DEA device. In this paper we advance the capabilities of DES further to form volatile memory elements. A set reset flip-flop with inverted reset line was developed based on DES and DEA. With a 3200V supply the flip-flop behaved appropriately and demonstrated the creation of dielectric elastomer memory capable of changing state in response to 1 second long set and reset pulses. This memory opens up applications such as oscillator, de-bounce, timing, and sequential logic circuits; all of which could be distributed throughout biomimetic actuator arrays. Future work will include miniaturisation to improve response speed, implementation into more complex circuits, and investigation of longer lasting and more sensitive switching materials.

  2. Evaluation of a theoretical model of perceptual accuracy and self-management behavior in pediatric diabetes

    E-print Network

    Lane, Mariella Marie

    2005-11-01

    This study evaluated a model of perceptual accuracy and self-management behavior in pediatric diabetes. Participants were 169 children and adolescents (10-18 years) attending diabetes summer camps. Error grid analysis quantified global perceptual...

  3. 1) Title of the paper: A perceptually driven hybrid additive-multiplicative watermarking

    E-print Network

    Autrusseau, Florent

    Cover Page 1) Title of the paper: A perceptually driven hybrid additive-multiplicative watermarking hybrid additive-multiplicative watermarking technique in the wavelet domain}, booktitle = {Electronic Imaging, Media Watermarking, Security and Forensics XIII}, year = {2011} } #12;A perceptually driven

  4. Evaluation of a theoretical model of perceptual accuracy and self-management behavior in pediatric diabetes 

    E-print Network

    Lane, Mariella Marie

    2005-11-01

    This study evaluated a model of perceptual accuracy and self-management behavior in pediatric diabetes. Participants were 169 children and adolescents (10-18 years) attending diabetes summer camps. Error grid analysis quantified global perceptual...

  5. Trinary Associative Memory Would Recognize Machine Parts

    NASA Technical Reports Server (NTRS)

    Liu, Hua-Kuang; Awwal, Abdul Ahad S.; Karim, Mohammad A.

    1991-01-01

    Trinary associative memory combines merits and overcomes major deficiencies of unipolar and bipolar logics by combining them in three-valued logic that reverts to unipolar or bipolar binary selectively, as needed to perform specific tasks. Advantage of associative memory: one obtains access to all parts of it simultaneously on basis of content, rather than address, of data. Consequently, used to exploit fully parallelism and speed of optical computing.

  6. Emerging sensing techniques for emerging memories

    Microsoft Academic Search

    Yiran Chen; Hai Li

    2011-01-01

    Among all emerging memories, Spin-Transfer Torque Random Access Memory (STT-RAM) has shown many promising features such as fast access speed, nonvolatility, compatibility to CMOS process and excellent scalability. However, large process variations of both magnetic tunneling junction (MTJ) and MOS transistor severely limit the yield of STT-RAM chips. In this work, we present a recently proposed sensing technique called nondestructive

  7. Can Flash Memory Help in Model Checking?

    Microsoft Academic Search

    Jiri Barnat; Lubos Brim; Stefan Edelkamp; Damian Sulewski; Pavel Simecek

    2008-01-01

    As flash media become common and their capacities and speed grow, they are becoming a practical alternative for standard mechanical\\u000a drives. So far, external memory model checking algorithms have been optimized for mechanical hard disks corresponding to the\\u000a model of Aggarwal and Vitter [1]. Since flash memories are essentially different, the model of Aggarwal and Vitter no longer\\u000a describes their typical

  8. Separate neural processing of timbre dimensions in auditory sensory memory.

    PubMed

    Caclin, Anne; Brattico, Elvira; Tervaniemi, Mari; Näätänen, Risto; Morlet, Dominique; Giard, Marie-Hélène; McAdams, Stephen

    2006-12-01

    Timbre is a multidimensional perceptual attribute of complex tones that characterizes the identity of a sound source. Our study explores the representation in auditory sensory memory of three timbre dimensions (acoustically related to attack time, spectral centroid, and spectrum fine structure), using the mismatch negativity (MMN) component of the auditory event-related potential. MMN is elicited by a discriminable change in a sound sequence and reflects the detection of the discrepancy between the current stimulus and traces in auditory sensory memory. The stimuli used in the present study were carefully controlled synthetic tones. MMNs were recorded after changes along each of the three timbre dimensions and their combinations. Additivity of unidimensional MMNs and dipole modeling results suggest partially separate MMN generators for different timbre dimensions, reflecting their mainly separate processing in auditory sensory memory. The results expand to timbre dimensions a property of separation of the representation in sensory memory that has already been reported between basic perceptual attributes (pitch, loudness, duration, and location) of sound sources. PMID:17129184

  9. Investigation of fast initialization of spacecraft bubble memory systems

    NASA Technical Reports Server (NTRS)

    Looney, K. T.; Nichols, C. D.; Hayes, P. J.

    1984-01-01

    Bubble domain technology offers significant improvement in reliability and functionality for spacecraft onboard memory applications. In considering potential memory systems organizations, minimization of power in high capacity bubble memory systems necessitates the activation of only the desired portions of the memory. In power strobing arbitrary memory segments, a capability of fast turn on is required. Bubble device architectures, which provide redundant loop coding in the bubble devices, limit the initialization speed. Alternate initialization techniques are investigated to overcome this design limitation. An initialization technique using a small amount of external storage is demonstrated.

  10. Anger perceptually and conceptually narrows cognitive scope.

    PubMed

    Gable, Philip A; Poole, Bryan D; Harmon-Jones, Eddie

    2015-07-01

    For the last 50 years, research investigating the effect of emotions on scope of cognitive processing was based on models proposing that affective valence determined cognitive scope. More recently, our motivational intensity model suggests that this past work had confounded valence with motivational intensity. Research derived from this model supports the idea that motivational intensity, rather than affective valence, explains much of the variance emotions have on cognitive scope. However, the motivational intensity model is limited in that the empirical work has examined only positive affects high in approach and negative affects high in avoidance motivation. Thus, perhaps only approach-positive and avoidance-negative states narrow cognitive scope. The present research was designed to clarify these conceptual issues by examining the effect of anger, a negatively valenced approach-motivated state, on cognitive scope. Results revealed that anger narrowed attentional scope relative to a neutral state and that attentional narrowing to anger was similar to the attentional narrowing caused by high approach-motivated positive affects (Study 1). This narrowing of attention was related to trait approach motivation (Studies 2 and Study 3). Anger also narrowed conceptual cognitive categorization (Study 4). Narrowing of categorization related to participants' approach motivation toward anger stimuli. Together, these results suggest that anger, an approach-motivated negative affect, narrows perceptual and conceptual cognitive scope. More broadly, these results support the conceptual model that motivational intensity per se, rather than approach-positive and avoidance-negative states, causes a narrowing of cognitive scope. (PsycINFO Database Record PMID:26011662

  11. Flash Memory Garbage Collection in Hard Real-Time Systems 

    E-print Network

    Lai, Chien-An

    2012-10-19

    Due to advances in capacity, speed, and economics, NAND-based flash memory technology is increasingly integrated into all types of computing systems, ranging from enterprise servers to embedded devices. However, due to its ...

  12. [ME]morial

    E-print Network

    Lee, Beomki

    2015-01-01

    Challenging an archetypal relationship between collective memory and a multitude of traditional memorials, "[ME]morial" presents a new concept in memorial architecture based on the reinterpretation of Freud's and Bergson's ...

  13. Perceptual compression of magnitude-detected synthetic aperture radar imagery

    NASA Technical Reports Server (NTRS)

    Gorman, John D.; Werness, Susan A.

    1994-01-01

    A perceptually-based approach for compressing synthetic aperture radar (SAR) imagery is presented. Key components of the approach are a multiresolution wavelet transform, a bit allocation mask based on an empirical human visual system (HVS) model, and hybrid scalar/vector quantization. Specifically, wavelet shrinkage techniques are used to segregate wavelet transform coefficients into three components: local means, edges, and texture. Each of these three components is then quantized separately according to a perceptually-based bit allocation scheme. Wavelet coefficients associated with local means and edges are quantized using high-rate scalar quantization while texture information is quantized using low-rate vector quantization. The impact of the perceptually-based multiresolution compression algorithm on visual image quality, impulse response, and texture properties is assessed for fine-resolution magnitude-detected SAR imagery; excellent image quality is found at bit rates at or above 1 bpp along with graceful performance degradation at rates below 1 bpp.

  14. DCTune Perceptual Optimization of Compressed Dental X-Rays

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

    In current dental practice, x-rays of completed dental work are often sent to the insurer for verification. It is faster and cheaper to transmit instead digital scans of the x-rays. Further economies result if the images are sent in compressed form. DCtune is a technology for optimizing DCT quantization matrices to yield maximum perceptual quality for a given bit-rate, or minimum bit-rate for a given perceptual quality. In addition, the technology provides a means of setting the perceptual quality of compressed imagery in a systematic way. The purpose of this research was, with respect to dental x-rays: (1) to verify the advantage of DCTune over standard JPEG; (2) to verify the quality control feature of DCTune; and (3) to discover regularities in the optimized matrices of a set of images. Additional information is contained in the original extended abstract.

  15. Adaptive shape coding for perceptual decisions in the human brain

    PubMed Central

    Kourtzi, Zoe; Welchman, Andrew E.

    2015-01-01

    In its search for neural codes, the field of visual neuroscience has uncovered neural representations that reflect the structure of stimuli of variable complexity from simple features to object categories. However, accumulating evidence suggests an adaptive neural code that is dynamically shaped by experience to support flexible and efficient perceptual decisions. Here, we review work showing that experience plays a critical role in molding midlevel visual representations for perceptual decisions. Combining behavioral and brain imaging measurements, we demonstrate that learning optimizes feature binding for object recognition in cluttered scenes, and tunes the neural representations of informative image parts to support efficient categorical judgements. Our findings indicate that similar learning mechanisms may mediate long-term optimization through development, tune the visual system to fundamental principles of feature binding, and optimize feature templates for perceptual decisions. PMID:26024511

  16. Perceptual binding of sensory events: the inclusive characteristics model.

    PubMed

    Sergin, V Ya

    2003-10-01

    A conceptual model of a perceptual system is proposed, in which each neural level forms characteristics inclusive of the data held in the underlying level. As a result, the stimulus field can be expressed as a hierarchically ordered set of overlying sensory characteristics: from sensory features to higher inclusive characteristics binding sensory data to form whole images and scenes. Specific patterns of electrical activity reflecting inclusive characteristics are transmitted via reverse projections from the upper neural levels to the lower. This forms a downward excitation transmission cascade, stimulating those neural structures whose signals correspond to the higher inclusive characteristics of the given perceptual act. It is demonstrated that these mechanisms are in good agreement with experimental data obtained from psychological and neurophysiological studies and may support the binding of sensory events at all perceptual levels. PMID:14635989

  17. Improving vision in adult amblyopia by perceptual learning

    PubMed Central

    Polat, Uri; Ma-Naim, Tova; Belkin, Michael; Sagi, Dov

    2004-01-01

    Practicing certain visual tasks leads, as a result of a process termed “perceptual learning,” to a significant improvement in performance. Learning is specific for basic stimulus features such as local orientation, retinal location, and eye of presentation, suggesting modification of neuronal processes at the primary visual cortex in adults. It is not known, however, whether such low-level learning affects higher-level visual tasks such as recognition. By systematic low-level training of an adult visual system malfunctioning as a result of abnormal development (leading to amblyopia) of the primary visual cortex during the “critical period,” we show here that induction of low-level changes might yield significant perceptual benefits that transfer to higher visual tasks. The training procedure resulted in a 2-fold improvement in contrast sensitivity and in letter-recognition tasks. These findings demonstrate that perceptual learning can improve basic representations within an adult visual system that did not develop during the critical period. PMID:15096608

  18. Improving vision in adult amblyopia by perceptual learning.

    PubMed

    Polat, Uri; Ma-Naim, Tova; Belkin, Michael; Sagi, Dov

    2004-04-27

    Practicing certain visual tasks leads, as a result of a process termed "perceptual learning," to a significant improvement in performance. Learning is specific for basic stimulus features such as local orientation, retinal location, and eye of presentation, suggesting modification of neuronal processes at the primary visual cortex in adults. It is not known, however, whether such low-level learning affects higher-level visual tasks such as recognition. By systematic low-level training of an adult visual system malfunctioning as a result of abnormal development (leading to amblyopia) of the primary visual cortex during the "critical period," we show here that induction of low-level changes might yield significant perceptual benefits that transfer to higher visual tasks. The training procedure resulted in a 2-fold improvement in contrast sensitivity and in letter-recognition tasks. These findings demonstrate that perceptual learning can improve basic representations within an adult visual system that did not develop during the critical period. PMID:15096608

  19. Perceptual awareness and its neural basis: bridging experimental and theoretical paradigms

    E-print Network

    Perceptual awareness and its neural basis: bridging experimental and theoretical paradigms Antonino scientific challenge of our times, and perceptual awareness is an integral part of it. This Theme Issue aims to provide a timely focus on crucial insights from leading scientists on perceptual awareness and its neural

  20. The Development of Perceptual Grouping Biases in Infancy: A Japanese-English Cross-Linguistic Study

    ERIC Educational Resources Information Center

    Yoshida, Katherine A.; Iversen, John R.; Patel, Aniruddh D.; Mazuka, Reiko; Nito, Hiromi; Gervain, Judit; Werker, Janet F.

    2010-01-01

    Perceptual grouping has traditionally been thought to be governed by innate, universal principles. However, recent work has found differences in Japanese and English speakers' non-linguistic perceptual grouping, implicating language in non-linguistic perceptual processes (Iversen, Patel, & Ohgushi, 2008). Two experiments test Japanese- and…

  1. Human Perceptual Performance With Nonliteral Imagery: Region Recognition and Texture-Based Segmentation

    ERIC Educational Resources Information Center

    Essock, Edward A.; Sinai, Michael J.; DeFord, Kevin; Hansen, Bruce C.; Srinivasan, Narayanan

    2004-01-01

    In this study the authors address the issue of how the perceptual usefulness of nonliteral imagery should be evaluated. Perceptual performance with nonliteral imagery of natural scenes obtained at night from infrared and image-intensified sensors and from multisensor fusion methods was assessed to relate performance on 2 basic perceptual tasks to…

  2. Effects of Perceptual Learning Style Preferences on L2 Lexical Inferencing

    ERIC Educational Resources Information Center

    Shen, Ming-yueh

    2010-01-01

    The purpose of this pilot study was to examine the effects of perceptual learning style preferences on L2 lexical inferencing and whether learners with certain perceptual learning styles benefited more from an explicitly instructional program. Joy Reid's (1995) Perceptual Learning Style Preferences (PLSP) Inventory and a lexical inferencing test…

  3. Perceptual representations of parametrically-defined and natural objects comparing vision and haptics

    Microsoft Academic Search

    N. Gaissert; Christian Wallraven

    2010-01-01

    Studies concerning how the brain might represent objects by means of a perceptual space have primarily focused on the visual domain. Here we want to show that the haptic modality can equally well recover the underlying structure of a physical object space, forming a perceptual space that is highly congruent to the visual perceptual space. By varying three shape parameters

  4. Strength of Perceptual Experience Predicts Word Processing Performance Better than Concreteness or Imageability

    ERIC Educational Resources Information Center

    Connell, Louise; Lynott, Dermot

    2012-01-01

    Abstract concepts are traditionally thought to differ from concrete concepts by their lack of perceptual information, which causes them to be processed more slowly and less accurately than perceptually-based concrete concepts. In two studies, we examined this assumption by comparing concreteness and imageability ratings to a set of perceptual

  5. Perceptual and Cognitive Load Interact to Control the Spatial Focus of Attention

    ERIC Educational Resources Information Center

    Linnell, Karina J.; Caparos, Serge

    2011-01-01

    Caparos and Linnell (2009, 2010) used a variable-separation flanker paradigm to show that (a) when cognitive load is low, increasing perceptual load causes spatial attention to focus and (b) when perceptual load is high, decreasing cognitive load causes spatial attention to focus. Here, we tested whether the effects of perceptual and cognitive…

  6. Naval Research Laboratory Memorandum Report, 2003 Perceptual and Ergonomic Issues in

    E-print Network

    Swan II, J. Edward

    Naval Research Laboratory Memorandum Report, 2003 1 Perceptual and Ergonomic Issues in Mobile paradigm, the field needs a much better understanding of the fundamental perceptual and ergonomic issues aimed at both understanding the fundamental perceptual and ergonomic issues in AR display

  7. Simultaneous detection of vertical and horizontal text lines based on perceptual organisation

    E-print Network

    Faure, Claudie

    of the method: The caption lines Perceptual grouping Detection of vertical and horizontal text lines #12 lines #12;#12;#12;#12;Conclusion How do readers detect text lines? Perceptually-based method ReliableSimultaneous detection of vertical and horizontal text lines based on perceptual organisation

  8. Can speeding be justified?

    Microsoft Academic Search

    Sarah Redshaw

    There is a lot of community acceptance of speeding and the kinds of justifications that are given centre around people regarding themselves as good enough drivers to decide what speed to travel at for themselves. There is an evident lack of acceptance of speed limits. It seems that no matter how much better roads are and with speed limits up

  9. Cognitive, Perceptual-Speed, and Psychomotor Determinants of Individual Differences During Skill Acquisition

    Microsoft Academic Search

    Phillip L. Ackerman; Anna T. Cianciolo

    2000-01-01

    The authors describe a series of experiments that explore 3 major ability determinants of individual differences in skill acquisition in the context of prior theory (e.g., P. L. Ackerman, 1988) and subsequent empirical and theoretical research. Experiment 1 assessed the predictability of individual differences in asymptotic skill levels on the Kanfer–Ackerman Air Traffic Controller (ATC) task. Experiment 2 provided an

  10. Non-volatile memory based on the ferroelectric photovoltaic effect.

    PubMed

    Guo, Rui; You, Lu; Zhou, Yang; Lim, Zhi Shiuh; Zou, Xi; Chen, Lang; Ramesh, R; Wang, Junling

    2013-01-01

    The quest for a solid state universal memory with high-storage density, high read/write speed, random access and non-volatility has triggered intense research into new materials and novel device architectures. Though the non-volatile memory market is dominated by flash memory now, it has very low operation speed with ~10??s programming and ~10?ms erasing time. Furthermore, it can only withstand ~10(5) rewriting cycles, which prevents it from becoming the universal memory. Here we demonstrate that the significant photovoltaic effect of a ferroelectric material, such as BiFeO3 with a band gap in the visible range, can be used to sense the polarization direction non-destructively in a ferroelectric memory. A prototype 16-cell memory based on the cross-bar architecture has been prepared and tested, demonstrating the feasibility of this technique. PMID:23756366

  11. Non-volatile memory based on the ferroelectric photovoltaic effect

    PubMed Central

    Guo, Rui; You, Lu; Zhou, Yang; Shiuh Lim, Zhi; Zou, Xi; Chen, Lang; Ramesh, R.; Wang, Junling

    2013-01-01

    The quest for a solid state universal memory with high-storage density, high read/write speed, random access and non-volatility has triggered intense research into new materials and novel device architectures. Though the non-volatile memory market is dominated by flash memory now, it has very low operation speed with ~10??s programming and ~10?ms erasing time. Furthermore, it can only withstand ~105 rewriting cycles, which prevents it from becoming the universal memory. Here we demonstrate that the significant photovoltaic effect of a ferroelectric material, such as BiFeO3 with a band gap in the visible range, can be used to sense the polarization direction non-destructively in a ferroelectric memory. A prototype 16-cell memory based on the cross-bar architecture has been prepared and tested, demonstrating the feasibility of this technique. PMID:23756366

  12. Electrophysiological correlates associated with contributions of perceptual and conceptual fluency to familiarity

    PubMed Central

    Wang, Wei; Li, Bingbing; Gao, Chuanji; Xiao, Xin; Guo, Chunyan

    2015-01-01

    The present research manipulated the fluency of unstudied items using masked repetition priming procedures during an explicit recognition test. Based on fluency-attribution accounts, which posit that familiarity can be driven by multiple forms of fluency, the relationship between masked priming-induced fluency and familiarity was investigated. We classified pictographic characters into High-Meaningfulness (High-M) and Low-Meaningfulness (Low-M) categories on the basis of subjective meaningfulness ratings and identified the distinct electrophysiological correlates of perceptual and conceptual fluency. The two types of fluency differed in associated ERP effects: 150–250 ms effects for perceptual fluency and FN400 effects for conceptual fluency. The ERPs of Low-M MP-same (items that were preceded by matching masked items) false alarms were more positive than correct rejections during 150–250 ms, whereas the ERPs of High-M MP-same false alarms were more positive than correct rejections during 300–500 ms. The topographic patterns of FN400 effects between High-M MP-same false alarms and Low-M MP-same false alarms were not different from those of High-M hits and Low-M hits. These results indicate that both forms of fluency can contribute to familiarity, and the neural correlates of conceptual fluency are not different from those of conceptual priming induced by prior study-phase exposure. We conclude that multiple neural signals potentially contribute to recognition memory, such as numerous forms of fluency differing in terms of their time courses.

  13. A compact PE memory for vision chips

    NASA Astrophysics Data System (ADS)

    Cong, Shi; Zhe, Chen; Jie, Yang; Nanjian, Wu; Zhihua, Wang

    2014-09-01

    This paper presents a novel compact memory in the processing element (PE) for single-instruction multiple-data (SIMD) vision chips. The PE memory is constructed with 8 × 8 register cells, where one latch in the slave stage is shared by eight latches in the master stage. The memory supports simultaneous read and write on the same address in one clock cycle. Its compact area of 14.33 ?m2/bit promises a higher integration level of the processor. A prototype chip with a 64 × 64 PE array is fabricated in a UMC 0.18 ?m CMOS technology. Five types of the PE memory cell structure are designed and compared. The testing results demonstrate that the proposed PE memory architecture well satisfies the requirement of the vision chip in high-speed real-time vision applications, such as 1000 fps edge extraction.

  14. Worthington Memory

    NSDL National Science Digital Library

    This Online Scrapbook of Worthington History is a collaborative project between the Worthington (Ohio) Libraries and the Worthington Historical Society to present local history materials. Visitors can search or browse the digitized collection, currently over 117 photographs and documents. Those unfamiliar with Worthington can use the browse feature to retrieve collection items organized into broad categories such as Arts, Architecture, Agriculture, Business and Commerce, or by decade from 1800 to 2002. Documentation, such as selection criteria, and a 36-page manual "Worthington Memory Digital Imaging Workflow" is provided, making Worthington Memory a handy resource for other public libraries wishing to begin a local history digitization project.

  15. Memory clinics

    PubMed Central

    Jolley, D; Benbow, S M; Grizzell, M

    2006-01-01

    Memory clinics were first described in the 1980s. They have become accepted worldwide as useful vehicles for improving practice in the identification, investigation, and treatment of memory disorders, including dementia. They are provided in various settings, the setting determining clientele and practice. All aim to facilitate referral from GPs, other specialists, or by self referral, in the early stages of impairment, and to avoid the stigma associated with psychiatric services. They bring together professionals with a range of skills for the benefit of patients, carers, and colleagues, and contribute to health promotion, health education, audit, and research, as well as service to patients. PMID:16517802

  16. Reactivating personal memory 1 RUNNING HEAD: Reactivating personal memory

    E-print Network

    Schacter, Daniel

    Reactivating personal memory 1 RUNNING HEAD: Reactivating personal memory Modifying memory: Selectively enhancing and updating personal memories for a museum; Reactivating personal memory 2 Abstract Memory can be modified when reactivated

  17. Look before you leap: sensory memory improves decision making.

    PubMed

    Vlassova, Alexandra; Pearson, Joel

    2013-09-01

    Simple decisions require the processing and evaluation of perceptual and cognitive information, the formation of a decision, and often the execution of a motor response. This process involves the accumulation of evidence over time until a particular choice reaches a decision threshold. Using a random-dot-motion stimulus, we showed that simply delaying responses after the stimulus offset can almost double accuracy, even in the absence of new incoming visual information. However, under conditions in which the otherwise blank interval was filled with a sensory mask or concurrent working memory load was high, performance gains were lost. Further, memory and perception showed equivalent rates of evidence accumulation, suggesting a high-capacity memory store. We propose an account of continued evidence accumulation by sequential sampling from a simultaneously decaying memory trace. Memories typically decay with time, hence immediate inquiry trumps later recall from memory. However, the results we report here show the inverse: Inspecting a memory trumps viewing the actual object. PMID:23818654

  18. 64K dynamic 1\\/N fractional device bipolar memory

    Microsoft Academic Search

    J. Selleck; R. Kenyon; D. Gaffney; F. Wiedman; A. Bhattacharyya; P. Mollier

    1980-01-01

    This report will cover a 1\\/N fractional device bipolar memory cell - the FET one-device memory cell equivalent - noting that by reversing the orientation of the transistor and capacitor, the density, thin dielectric and polysilicon techniques of FET technology can be combined with the speed of bipolar technology,

  19. Multilayer plated wire shows promise as memory device

    NASA Technical Reports Server (NTRS)

    Kadish, D.

    1968-01-01

    Multilayer plated wire memory system surpasses planar thin film memories because of its high speed, simplicity, and high output. The device consists of 5 mil Be-Cu wire plated with Ni-Fe alloy about 1 micron thick crossed orthogonally by word lines.

  20. Toward the Efficient Use of Multiple Explicitly Managed Memory Subsystems

    E-print Network

    Balaji, Pavan

    ~na Mathematics and Computer Science Division Argonne National Laboratory Argonne, IL 60439 Email: apenya@anl.gov Pavan Balaji Mathematics and Computer Science Division Argonne National Laboratory Argonne, IL 60439 and memory access speeds, by taking advantage of the benefits these memory technologies provide. Compute