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The cognitive aspect of second language learning, specifically by immersion method, is discussed from a biological perspective. The approach taken is that of "connectionism," a recently-developed theoretical and experimental approach to human cognition. It is argued that while general cognitive functioning is unaffected by language immersion, immersion students are subject to shifts in information processing strategy toward the visual system and away from the auditory system, due to low speech comprehension ability, and that development of such a bias is a natural outcome of brain structure and the mechanics of information processing in the human brain. It is further proposed that any cognitive advantages and disadvantages accrued by learners in immersion situations are determined by the information processing demands of the particular measures of cognitive performance used. Academic achievement results for this group are also explained by how achievement is defined and success measured, from the perspective of information processing. Contains 24 references. (MSE)

This publication is a compilation of the papers presented at the NASA conference on Visual Information Processing for Television and Telerobotics. The conference was held at the Williamsburg Hilton, Williamsburg, Virginia on May 10 to 12, 1989. The conference was sponsored jointly by NASA Offices of Aeronautics and Space Technology (OAST) and Space Science and Applications (OSSA) and the NASA Langley Research Center. The presentations were grouped into three sessions: Image Gathering, Coding, and Advanced Concepts; Systems; and Technologies. The program was organized to provide a forum in which researchers from industry, universities, and government could be brought together to discuss the state of knowledge in image gathering, coding, and processing methods.

This study aims to explore wherther and how tasting actual drinks would affect visual information processing.

We study a new biologically motivated model for the Macaque monkey primary visual cortex which presents power-law avalanches after a visual stimulus. The signal propagates through all the layers of the model via avalanches that depend on network structure and synaptic parameter. We identify four different avalanche profiles as a function of the excitatory postsynaptic potential. The avalanches follow a size-duration scaling relation and present critical exponents that match experiments. The structure of the network gives rise to a regime of two characteristic spatial scales, one of which vanishes in the thermodynamic limit.

This article is from Frontiers in Psychology , volume 5 . Abstract When dissimilar stimuli are presented to the two eyes, only one stimulus dominates at a time while the other stimulus is invisible due to interocular suppression. When both stimuli are equally potent in competing for awareness, perception alternates spontaneously between the two stimuli, a phenomenon called binocular rivalry. However, when one stimulus is much stronger, e.g., due to higher contrast, the weaker stimulus can be suppressed for prolonged periods of time. A technique that has recently become very popular for the investigation of unconscious visual processing is continuous flash suppression (CFS): High-contrast dynamic patterns shown to one eye can render a low-contrast stimulus shown to the other eye invisible for up to minutes. Studies using CFS have produced new insights but also controversies regarding the types of visual information that can be processed unconsciously as well as the neural sites and the relevance of such unconscious processing. Here, we review the current state of knowledge in regard to neural processing of interocularly suppressed information. Focusing on recent neuroimaging findings, we discuss whether and to what degree such suppressed visual information is processed at early and more advanced levels of the visual processing hierarchy. We review controversial findings related to the influence of attention on early visual processing under interocular suppression, the putative differential roles of dorsal and ventral areas in unconscious object processing, and evidence suggesting privileged unconscious processing of emotional and other socially relevant information. On a more general note, we discuss methodological and conceptual issues, from practical issues of how unawareness of a stimulus is assessed to the overarching question of what constitutes an adequate operational definition of unawareness. Finally, we propose approaches for future research to resolve current controversies in this exciting research area.

Tri 1 – 2018/2019

Tri 1 – 2018/2019

Eye movements determine the location and velocity of the retinal image. Thus, to understand how we see it is necessary to understand both how eye movements are controlled and how they affect visual information processing. The proposed research is concerned with both problems, specifically: (1) the effect of expectations on smooth eye movements; (2) the effect of saccades and saccade-like stimulus perturbations on visual information processing; and (3) programming sequences of saccades.

Report of a 3 year investigation into the physiological structure of the mantis shrimp eye. This creature has the most advanced and most complex eye of any creature in nature, with many band-pass elements, including those outside of human viewing spectra. It also can see polarized light linear and circular, both directions

The result of a number of experiemental studies of human auditory and visual information processing behavior and their possible relationship to the student pilot's acquisition of flying skill were explored in terms of a conceptual model developed for this study. The results were interpreted in terms of the potential interfering effects of the intake of and response to information processed during flying tasks and in terms of the student pilot's nonoptimal information processing strategies during his acquisition of flying skill. It was concluded that the experimental procedures employed could be adapted sucessfully for research in the area and that the relationships found between information procesing and flying skill warranted their further study. (Author)

This book brings together papers presented at a conference on early experience and visual information processing in perceptual and reading disorders sponsored by the National Academy of Sciences. The goal of the conference was to integrate basic knowledge of structure and mechanisms of eye and brain with their function and their behavioral roles in perception, with the focus on underlying factors that may contribute to reading disorders. The first section discusses topics related to the role of the visual system: optical and oculomotor, retinal, and central neural factors. The second section discusses attentional and perceptual mechanisms. The third section discusses early experience and learning in visual information processing. The fourth section discusses the role of information processing in perceptual and reading disabilities. The fifth and final section discusses management of children with perceptual and reading disabilities. The introduction is written by Donald Lindsley and Francis Young. Individual papers are written by such authors as Jeanne Chall, Robert Boynton, Robert Doty, Roger Sperry, Richard Jung, George Sperling, Ira Hirsh, Merton Flom, William Mason, Robert Fantz, and H. Burtt Richardson, Jr. (TS)

This book brings together papers presented at a conference on early experience and visual information processing in perceptual and reading disorders sponsored by the National Academy of Sciences. The goal of the conference was to integrate basic knowledge of structure and mechanisms of eye and brain with their function and their behavioral roles in perception, with the focus on underlying factors that may contribute to reading disorders. The first section discusses topics related to the role of the visual system: optical and oculomotor, retinal, and central neural factors. The second section discusses attentional and perceptual mechanisms. The third section discusses early experience and learning in visual information processing. The fourth section discusses the role of information processing in perceptual and reading disabilities. The fifth and final section discusses management of children with perceptual and reading disabilities. The introduction is written by Donald Lindsley and Francis Young. Individual papers are written by such authors as Jeanne Chall, Robert Boynton, Robert Doty, Roger Sperry, Richard Jung, George Sperling, Ira Hirsh, Merton Flom, William Mason, Robert Fantz, and H. Burtt Richardson, Jr. (TS)

This book brings together papers presented at a conference on early experience and visual information processing in perceptual and reading disorders sponsored by the National Academy of Sciences. The goal of the conference was to integrate basic knowledge of structure and mechanisms of eye and brain with their function and their behavioral roles in perception, with the focus on underlying factors that may contribute to reading disorders. The first section discusses topics related to the role of the visual system: optical and oculomotor, retinal, and central neural factors. The second section discusses attentional and perceptual mechanisms. The third section discusses early experience and learning in visual information processing. The fourth section discusses the role of information processing in perceptual and reading disabilities. The fifth and final section discusses management of children with perceptual and reading disabilities. The introduction is written by Donald Lindsley and Francis Young. Individual papers are written by such authors as Jeanne Chall, Robert Boynton, Robert Doty, Roger Sperry, Richard Jung, George Sperling, Ira Hirsh, Merton Flom, William Mason, Robert Fantz, and H. Burtt Richardson, Jr. (TS)

The research completed over the last twelve months has included a number of studies concerned with evoked cortical potential correlates of visual stimulus processing in humans. The first experiment was conducted in order to replicate an earlier finding in which the amplitude of a relatively late positive component of the event related potential (ERP), known as the P3, was larger to a line orientation that required a 'yes' response than one that required a 'no'. The angular difference between the two lines was only 5 degrees. Another purpose was to assess the reliability of the better right hemisphere performance found with male subjects in the line orientation discrimination task used. In a second experiment, we examined the possibility of hemispheric asymmetry in response to two different colors (red and blue). The two hemispheres responded in essentially the same manner to the two colors. However, an interesting finding was the larger ERPs of both left and right hemispheres to the color blue, especially with central visual field stimulation. A third experiment was directed at the determination of whether the right hemisphere would be more sensitive to visual masking than the left, especially with a metacontrast paradigm which is dependent on spatial factors to produce the masking effect. A fourth experiment was performed to determine the relative responsivity of the two hemispheres to verbal (letter) and spatial (geometric form) stimuli.

A continuing problem in naval aviation is how to identify, prior to training, those individuals having the greatest likelihood to succeed in flight training. Since World War II the US Navy has been concerned with the development of selection tests to improve its capability to screen individuals desiring entry into flight training. Improved aviation personnel selection tests could reduce attrition, and consequently, the monetary losses associated with this attrition. Additionally, the Navy would expose fewer flight students to a potentially hazardous training situation. A research methodological problem associated with the development of candidate tests for predictive validation is: How do we design a test that measures abilities relevant for inclusion in validation studies? A methodology, Random Sampling of Domain Variances, was developed as a product of the Augmentation of Human Factors Engineering Technology Efforts Program. This methodology provided the basis for developing a complex visual information task designed to require many basic cognitive processing demands thought to be required in performing aviation display tasks. This complex visual display task should be further evaluated in a cross- validation study and then considered for implementation as a performance-based selection test. The method of Random Sampling of Domain Variances should be considered as a methodological tool in the design of future tests to be selected for validation studies. (sdw)

This report describes mathematical analysis, behavior experiments, and neurophysiological experiments aimed at determining the mechanisms of visual perception in insects. The behavioral experiments with the beetle Lixus indicate that spatial processing involving autocorrelation is being performed among the ommatidia of the eye. This processing was studied by means of an optomotor reaction involving a turning tendency with movement in the visual field. Visual processing in the beetle Lixus was also studied by means of microelectrode recording of electrical nervous activity. The electroretinogram (ERG) was measured for various visual stimuli and Bode diagrams were determined for small changes in light intensity. Nonlinear effects were also noted for large changes in light intensity. Spike potentials were obtained from a single cell which fired with a change in light intensity. Spike potentials were also obtained from the ventral nerve cord, anterior thoracic region, and motor nerve stump of the first joint of the right front leg. A functional model is proposed to explain the behavioral and neurophysiological results.

This article is from Frontiers in Human Neuroscience , volume 7 . Abstract Objective: Mismatch negativity (MMN) and P3 are unique ERP components that provide objective indices of human cognitive functions such as short-term memory and prediction. Bipolar disorder (BD) is an endogenous psychiatric disorder characterized by extreme shifts in mood, energy, and ability to function socially. BD patients usually show cognitive dysfunction, and the goal of this study was to access their altered visual information processing via visual MMN (vMMN) and P3 using windmill pattern stimuli.Methods: Twenty patients with BD and 20 healthy controls matched for age, gender, and handedness participated in this study. Subjects were seated in front of a monitor and listened to a story via earphones. Two types of windmill patterns (standard and deviant) and white circle (target) stimuli were randomly presented on the monitor. All stimuli were presented in random order at 200-ms durations with an 800-ms inter-stimulus interval. Stimuli were presented at 80% (standard), 10% (deviant), and 10% (target) probabilities. The participants were instructed to attend to the story and press a button as soon as possible when the target stimuli were presented. Event-related potentials (ERPs) were recorded throughout the experiment using 128-channel EEG equipment. vMMN was obtained by subtracting standard from deviant stimuli responses, and P3 was evoked from the target stimulus.Results: Mean reaction times for target stimuli in the BD group were significantly higher than those in the control group. Additionally, mean vMMN-amplitudes and peak P3-amplitudes were significantly lower in the BD group than in controls.Conclusions: Abnormal vMMN and P3 in patients indicate a deficit of visual information processing in BD, which is consistent with their increased reaction time to visual target stimuli.Significance: Both bottom-up and top-down visual information processing are likely altered in BD.

This article is from Frontiers in Human Neuroscience , volume 7 . Abstract Objective: Mismatch negativity (MMN) and P3 are unique ERP components that provide objective indices of human cognitive functions such as short-term memory and prediction. Bipolar disorder (BD) is an endogenous psychiatric disorder characterized by extreme shifts in mood, energy, and ability to function socially. BD patients usually show cognitive dysfunction, and the goal of this study was to access their altered visual information processing via visual MMN (vMMN) and P3 using windmill pattern stimuli.Methods: Twenty patients with BD and 20 healthy controls matched for age, gender, and handedness participated in this study. Subjects were seated in front of a monitor and listened to a story via earphones. Two types of windmill patterns (standard and deviant) and white circle (target) stimuli were randomly presented on the monitor. All stimuli were presented in random order at 200-ms durations with an 800-ms inter-stimulus interval. Stimuli were presented at 80% (standard), 10% (deviant), and 10% (target) probabilities. The participants were instructed to attend to the story and press a button as soon as possible when the target stimuli were presented. Event-related potentials (ERPs) were recorded throughout the experiment using 128-channel EEG equipment. vMMN was obtained by subtracting standard from deviant stimuli responses, and P3 was evoked from the target stimulus.Results: Mean reaction times for target stimuli in the BD group were significantly higher than those in the control group. Additionally, mean vMMN-amplitudes and peak P3-amplitudes were significantly lower in the BD group than in controls.Conclusions: Abnormal vMMN and P3 in patients indicate a deficit of visual information processing in BD, which is consistent with their increased reaction time to visual target stimuli.Significance: Both bottom-up and top-down visual information processing are likely altered in BD.

Limitations in the ability to temporarily represent information in visual working memory (VWM) are crucial for (visual) cognition. Whether VWM processing is dependent on an object’s saliency (i.e., how much it stands out) has been neglected in VWM research. Therefore, we developed a novel VWM task design that allows direct control over saliency. In three experiments with this task (on 10, 31, and 60 healthy adults, respectively), we consistently find that VWM performance is strongly and parametrically influenced by saliency and that both an object’s relative (to concurrently presented objects) and absolute saliency influence VWM processing. We also demonstrate that this effect is indeed due to bottom-up saliency, rather than differential fit between each object and the top-down attentional set. A simple computational model assuming that VWM performance is determined by the weighted sum of absolute and relative saliency accounts well for the observed data patterns.

This investigation estimates the magnitude of the relationship between social class and visual information processing rates, and compares the development curves of processing rate for advantaged and disadvantaged children. Subjects were grade school children in a metropolitan area of southwestern Michigan. Estimates of the information processing rate were obtained by tachistocopically presenting two stimuli to the subject. The interval between the stimuli required by the subject to process the first stimulus was that subject's information processing rate. Social class was quantified using Duncan's "Socioeconomic Index". Data analysis involved use of the Pearson correlation, multiple regression technique and analysis of variance. Results indicated that disadvantaged children do process visual information more slowly than advantaged children. The development curves for the two groups tend to converge as they proceed through school. (Author/CJ)

The visual detection of a concealed target involves the interaction of object characteristics and observer-related variables. This report briefly summarises object characteristics which may affect detectability, and then concentrates upon observer variables. Some of the physical limitations of the human optical system are mentioned. An information processing theory is reviewed and adopted as a model upon which some hypotheses are based. In the case of a search of a large, complex field, automatic processing of information may lead to the selection of likely target areas, however controlled search processes may be required to scan the information in an automatically selected array.

This project examined the effects menstruation may have on visual attention in women. A recent study examined electroencephalographic (EEG) gender differences using a visual object recognition task. Results indicated certain EEG amplitudes (specifically, P300 and N400) are greater in women than men. This study extended the previous findings to determine if these increased EEG amplitudes vary across menstrual phases. Eighteen female participants participated in a series of 3 EEG recording sessions using the same visual object recognition task from the previous study; 18 male participants completed this task once. Analyses from 15 of the 18 female and 16 of the 18 male participants support the previous finding of larger P300 amplitudes in response to relevant stimuli for women compared with men. While there was no distinctive N400 component in this study, there was a late negative (LN) component which was found to vary significantly between men and women. In addition, multiple visual evoked potential (VEP) components varied significantly across the menstrual cycle. In particular, the N200 component appeared to provide greater differences between menstrual phases than either the p300 or LN components; however, the results varied greatly by head location, The differentiation found with VEP components in response to the pop-out task used in this study provide support for basic visual processing variation across the menstrual cycle and between genders.

Researchers are concerned with the end-to-end performance of image gathering, coding, and processing. The applications range from high-resolution television to vision-based robotics, wherever the resolution, efficiency and robustness of visual information acquisition and processing are critical. For the presentation at this workshop, it is convenient to divide research activities into the following two overlapping areas: The first is the development of focal-plane processing techniques and technology to effectively combine image gathering with coding, with an emphasis on low-level vision processing akin to the retinal processing in human vision. The approach includes the familiar Laplacian pyramid, the new intensity-dependent spatial summation, and parallel sensing/processing networks. Three-dimensional image gathering is attained by combining laser ranging with sensor-array imaging. The second is the rigorous extension of information theory and optimal filtering to visual information acquisition and processing. The goal is to provide a comprehensive methodology for quantitatively assessing the end-to-end performance of image gathering, coding, and processing.

Tri 2 2016/2017

Information transfer between the operator and computer-generated display systems is an area where the human factors engineer discovers little useful design data relating human performance to system effectiveness. This study utilized a computer-driven, cathode-ray-tube graphic display to quantify human response speed in a sequential information processing task. The performance criteria was response time to sixteen cell elements of a square matrix display. A stimulus signal instruction specified selected cell locations by both row and column identification. An equal probable number code, from one to four, was assigned at random to the sixteen cells of the matrix and correspondingly required one of four, matched keyed-response alternatives. The display format corresponded to a sequence of diagnostic system maintenance events, that enable the operator to verify prime system status, engage backup redundancy for failed subsystem components, and exercise alternate decision-making judgements. The experimental task bypassed the skilled decision-making element and computer processing time, in order to determine a lower bound on the basic response speed for given stimulus/response hardware arrangement.

Information transfer between the operator and computer-generated display systems is an area where the human factors engineer discovers little useful design data relating human performance to system effectiveness. This study utilized a computer-driven, cathode-ray-tube graphic display to quantify human response speed in a sequential information processing task. The performance criteria was response time to sixteen cell elements of a square matrix display. A stimulus signal instruction specified selected cell locations by both row and column identification. An equal probable number code, from one to four, was assigned at random to the sixteen cells of the matrix and correspondingly required one of four, matched keyed-response alternatives. The display format corresponded to a sequence of diagnostic system maintenance events, that enable the operator to verify prime system status, engage backup redundancy for failed subsystem components, and exercise alternate decision-making judgements. The experimental task bypassed the skilled decision-making element and computer processing time, in order to determine a lower bound on the basic response speed for given stimulus/response hardware arrangement.

Includes bibliographies

Includes bibliographies

Two experiments investigated a change in the late positive activity (200 to 550 msec) of the visual evoked potential (VEP). This 'P2-effect,' maximal at the occiput, appeared related to cognitive aspects of information processing. Results did not support an interpretation of the P2-effect in cognitive terms (Experiment 1) but rather in terms of shifts in cortical arousal and in expectancy (Experiment 2). In both studies, subjects viewed letter-pair stimuli, e.g., HH or bD, responding when they saw a stimulus (SIGHT task), or when they determined whether the two letters were the same or different in either size or name (SIZE and NAME tasks). Reaction times increased from the SIGHT to the SIZE to the NAME task, objectifying the increase in task complexity. The P2-effect occurred with the increase in task complexity from the SIGHT to the SIZE task, but did not increase further in the NAME task or show asymmetry in relation to lateralized processing. In Experiment 2, slow wave shifts were observed. These slow waves revealed subject-specific ranges of cortical arousal. The P2-effect appeared to result primarily from continued or noncontinued expectancy following stimulus reception. This work demonstrates the difficulty involved in controlling for and evaluating the effects of shifts in cortical arousal and in expectancy during cognitive information processing. The results are relevant to the question of CNV-P300 dissociability.

Two experiments investigated a change in the late positive activity (200 to 550 msec) of the visual evoked potential (VEP). This 'P2-effect,' maximal at the occiput, appeared related to cognitive aspects of information processing. Results did not support an interpretation of the P2-effect in cognitive terms (Experiment 1) but rather in terms of shifts in cortical arousal and in expectancy (Experiment 2). In both studies, subjects viewed letter-pair stimuli, e.g., HH or bD, responding when they saw a stimulus (SIGHT task), or when they determined whether the two letters were the same or different in either size or name (SIZE and NAME tasks). Reaction times increased from the SIGHT to the SIZE to the NAME task, objectifying the increase in task complexity. The P2-effect occurred with the increase in task complexity from the SIGHT to the SIZE task, but did not increase further in the NAME task or show asymmetry in relation to lateralized processing. In Experiment 2, slow wave shifts were observed. These slow waves revealed subject-specific ranges of cortical arousal. The P2-effect appeared to result primarily from continued or noncontinued expectancy following stimulus reception. This work demonstrates the difficulty involved in controlling for and evaluating the effects of shifts in cortical arousal and in expectancy during cognitive information processing. The results are relevant to the question of CNV-P300 dissociability.

Includes bibliographical references (pages 369-386) and index

Includes bibliographical references (pages 369-386) and index

Tri 1 2019/2020

Eight autistic children and young adolescents (mean age 12.9 years) were compared to normal chronological age controls. Ss were required to discriminate briefly presented visual stimuli when they were preceded or followed by a visual noise mask and when they were not. The minimum stimulus exposure duration for criterion identification of unmasked letters, the critical stimulus duration, was determined first. Subsequently, Ss were required to identify the letters under conditions of forward and backward masking. Autistic Ss showed a slight deficiency in relation to equal chronological age normals in their ability to discriminate unmasked letters. When this deficiency was controlled for, however, they did not differ from the controls in the visual masking experiment. Results provided support for the notion of a discontinuity between the disorders of autism, mental retardation, and schizophrenia. (Author)

Eight autistic children and young adolescents (mean age 12.9 years) were compared to normal chronological age controls. Ss were required to discriminate briefly presented visual stimuli when they were preceded or followed by a visual noise mask and when they were not. The minimum stimulus exposure duration for criterion identification of unmasked letters, the critical stimulus duration, was determined first. Subsequently, Ss were required to identify the letters under conditions of forward and backward masking. Autistic Ss showed a slight deficiency in relation to equal chronological age normals in their ability to discriminate unmasked letters. When this deficiency was controlled for, however, they did not differ from the controls in the visual masking experiment. Results provided support for the notion of a discontinuity between the disorders of autism, mental retardation, and schizophrenia. (Author)

Eight autistic children and young adolescents (mean age 12.9 years) were compared to normal chronological age controls. Ss were required to discriminate briefly presented visual stimuli when they were preceded or followed by a visual noise mask and when they were not. The minimum stimulus exposure duration for criterion identification of unmasked letters, the critical stimulus duration, was determined first. Subsequently, Ss were required to identify the letters under conditions of forward and backward masking. Autistic Ss showed a slight deficiency in relation to equal chronological age normals in their ability to discriminate unmasked letters. When this deficiency was controlled for, however, they did not differ from the controls in the visual masking experiment. Results provided support for the notion of a discontinuity between the disorders of autism, mental retardation, and schizophrenia. (Author)

This research produced a descriptive classification of the task behaviors and cognitive processing associated with performing a beyond-visual- range (BVR) air combat mission. An F-15C defensive counter air mission scenario was analyzed to identify the critical tactical decisions required of the pilot, the information that must be processed in order to make these decisions, and the overt behaviors associated with pilots' information processing. The goal of this classification scheme was to determine observable behaviors that can be used as overt indicators of cognitive information processing. For future research purposes, the classification will provide a framework for identifying observable task behaviors that may be worthy candidates for developing and testing measures of performance. Such measures are essential for assessing the effectiveness of simulator-based training programs for enhancing the cognitive skills necessary for BVR employment.

In man-machine design, it is important to quantify the reaction time components instead of simply determining the lump-sum reaction time to stimulus. The primary purpose of this thesis was to investigate the reaction time components, such as visual perception and muscle response time, and to quantify them by separating from their aggregated sum. The prime example, traffic-signal cognition simulation was used to examine human reaction time to signal change. With a modified computer program that stimulates the driver's approach to the intersection, we measured the subject's reaction times and examined behavioral patterns. Twelve subjects were involved in the experiment. A logistic regression procedure was applied to the data to define subjects' choices at different distances. Decision process time and the conflicting decision area were examined. Logistic regression was used to reveal the distribution of the conflicting decision area and muscle response time. The results revealed the visual perception time distribution. The most important part of total reaction time was visual perception. overall, the study showed the possibility of quantifying the reaction time components by using a simple computer simulation.

The objective of this research project was to investigate how emotion influences visual information processing and the neural correlates of the effects. Behavioral studies were proposed to address three issues. The first issue is related to the automaticity of processing task-irrelevant emotional features. The second issue is associated with the effect of positive affect on visual information processing and the third issue addresses the effect of capacity limitation on processing emotional information in a dynamic environment. The third issue was base on imaging experiments to understand the neural mechanisms of the impact of emotion on visual information processing. Progress is described.

Food information has a high reward value for human beings, and may be more so for those who are overweight or obese. Stimuli with high reward value may be particularly conspicuous, demanding our attention even when we are attending to something else. Yet, the nature and neural signals of potential biased processing of food information remains unclear. Moreover, despite decades of research, a reliable measure of food information processing remains elusive, making it a methodological bottleneck in obesity and disordered eating research. To address the nature of biased attention processing, we ask 1) how attention is biased toward two cardinal properties of food information, namely, healthfulness and tastiness, even though the food information is irrelevant to the task at hand; and 2) whether and how such processing might be dependent on the demandingness of the central task (i.e., perceptual load). In our previous study which has been preregistered, we recruited 32 participants and measured their responses to infrequent visual food information embedded in streams of other visual objects in EEG, specifically, by using a variant of steady-state visual evoked potential (SSVEP), oddball fast periodic visual stimulation (FPVS). The infrequent food objects (i.e., oddballs) are one of four different combinations in different trials based on healthfulness and tastiness: 1) high healthfulness and high tastiness; 1) high healthfulness and low tastiness; 3) low healthfulness and high tastiness; and 4) low healthfulness and low tastiness. The perceptual load of the central task is either low (detection of a certain color of letters) or high (detection of certain combinations of color and identity of letters). In this study, the results demonstrated robust and reliable implicit categorization of food information at the individual level for all 32 participants, with the effect not modulated by perceptual load or tastiness (but might be by healthfulness). Since oddball FPVS is a novel paradigm applied to studying food information processing, it would be critical to replicate the findings in order to develop FPVS as a reliable measure of food information processing as well as apply this tool to obesity or other clinical sample with eating disorders. In particular, the modulating effect of healthfulness observed was not salient and requires further evidence. Furthermore, the lack of modulation by tastiness and perceptual load also warrants replication. Therefore, we plan to conduct a replication study with the same paradigm and sample size to validate our previous findings.

Food information has a high reward value for human beings, and may be more so for those who are overweight or obese. Stimuli with high reward value may be particularly conspicuous, demanding our attention even when we are attending to something else. Yet, the nature and neural signals of potential biased processing of food information remains unclear. Moreover, despite decades of research, a reliable measure of food information processing remains elusive, making it a methodological bottleneck in obesity and disordered eating research. To address the nature of biased attention processing, we ask 1) how attention is biased toward two cardinal properties of food information, namely, healthfulness and tastiness, even though the food information is irrelevant to the task at hand; and 2) whether and how such processing might be dependent on the demandingness of the central task (i.e., perceptual load). In our previous study which has been preregistered, we recruited 32 participants and measured their responses to infrequent visual food information embedded in streams of other visual objects in EEG, specifically, by using a variant of steady-state visual evoked potential (SSVEP), oddball fast periodic visual stimulation (FPVS). The infrequent food objects (i.e., oddballs) are one of four different combinations in different trials based on healthfulness and tastiness: 1) high healthfulness and high tastiness; 1) high healthfulness and low tastiness; 3) low healthfulness and high tastiness; and 4) low healthfulness and low tastiness. The perceptual load of the central task is either low (detection of a certain color of letters) or high (detection of certain combinations of color and identity of letters). In this study, the results demonstrated robust and reliable implicit categorization of food information at the individual level for all 32 participants, with the effect not modulated by perceptual load or tastiness (but might be by healthfulness). Since oddball FPVS is a novel paradigm applied to studying food information processing, it would be critical to replicate the findings in order to develop FPVS as a reliable measure of food information processing as well as apply this tool to obesity or other clinical sample with eating disorders. In particular, the modulating effect of healthfulness observed was not salient and requires further evidence. Furthermore, the lack of modulation by tastiness and perceptual load also warrants replication. Therefore, we plan to conduct a replication study with the same paradigm and sample size to validate our previous findings.

The objective is to find out how saccadic eye movements (voluntary jumps of the eye) can be directed accurately to chosen targets within natural, patterned visual environments. An effective saccadic scanning mechanism must consist of: (1) a selective filter that determines which object serves as the saccadic target, and (2) a spatial-pooling mechanism that computes a single, precise saccadic landing position. Major findings were: (1) a single attentional filer serves both saccadic eye movements and perception; (2) attentional requirements of saccades are modest; (3) it is easier to divide attention between two widely-spaced targets than two closely-spaced targets; (4) the spatial-pooling process guides saccades to a central landing position within spatially-extended targets with a high degree of precision; (5) the central landing position is near the center of gravity; (6) the central landing position and the precision of the saccade depends on target size but not on spatial frequency content, contrast, or shape.

Continuing work on the three-systems-theory of visual motion perception: (I) Isoluminant chromatic motion is perceived by and only by the third-order motion system. (2) New illusion. Cancelling salience modulation in the third-order motion system causes brightly colored moving red-green gratings to appear to be motionless (motion standstill illusion) that gives considerable insight into the mechanisms of object perception. (3) A prediction that motion could be used to provide amplification of apparent contrast was verified, with amplifications 5x. (4) Amplification procedures were used to construct purified stimuli to stimulate each motion system individually, and (5) to measure the amplification produced by selective attention to a feature. (6) Developed computational models oi attentional amplification of features and of the movement dynamics of spatial attention. The spatial attentional mode was investigated with a new paradigm (gating spatial attention) to enable measurements of iconic memory uncontaminated by attention dynamics and to demonstrate that a new attention window' open concurrently at all points within the window. (7) The spatial attention model predicts 90% of the variance in a huge data set (approximately 500 points per observer from 20,000 trials) and encompasses the major attention paradigms. (All items plus more are fully described in publications.)

Visual perception was investigated using spatial filters that are constrained by biological data. This report has four major parts: (1) a theoretical background to Fourier analysis; (2) a review of the literature relating to the spatial filtering characteristics of mammalian visual systems; (3) visual information processing in terms of spatial filtering; (4) the relating of contrast sensitivity to the identification of complex objects. The common denominator to all the investigations is spatial filtering. The major goal of the dissertation was the attempt to explain certain aspects of visual perception using a single concept: filtering. (Author)

Visual perception was investigated using spatial filters that are constrained by biological data. This report has four major parts: (1) a theoretical background to Fourier analysis; (2) a review of the literature relating to the spatial filtering characteristics of mammalian visual systems; (3) visual information processing in terms of spatial filtering; (4) the relating of contrast sensitivity to the identification of complex objects. The common denominator to all the investigations is spatial filtering. The major goal of the dissertation was the attempt to explain certain aspects of visual perception using a single concept: filtering. (Author)

Visual perception was investigated using spatial filters that are constrained by biological data. This report has four major parts: (1) a theoretical background to Fourier analysis; (2) a review of the literature relating to the spatial filtering characteristics of mammalian visual systems; (3) visual information processing in terms of spatial filtering; (4) the relating of contrast sensitivity to the identification of complex objects. The common denominator to all the investigations is spatial filtering. The major goal of the dissertation was the attempt to explain certain aspects of visual perception using a single concept: filtering. (Author)

Visual perception was investigated using spatial filters that are constrained by biological data. This report has four major parts: (1) a theoretical background to Fourier analysis; (2) a review of the literature relating to the spatial filtering characteristics of mammalian visual systems; (3) visual information processing in terms of spatial filtering; (4) the relating of contrast sensitivity to the identification of complex objects. The common denominator to all the investigations is spatial filtering. The major goal of the dissertation was the attempt to explain certain aspects of visual perception using a single concept: filtering. (Author)

This study uses the 7.5% carbon dioxide model of anxiety induction to investigate the effects of state anxiety on visual and auditory information processing. Participants will undergo two inhalations (of 7.5% CO2-enriched air and medical air) and complete two tasks that present clear and degraded visual and auditory stimuli. We hypothesise that 7.5% CO2 inhalation will be associated with impaired performance and this effect will be greatest when stimuli are degraded.

Food information has a high reward value for human beings, and may be more so for those who are overweight or obese. Stimuli with high reward value may be particularly conspicuous, demanding our attention even when we are attending to something else. Yet, the nature and neural signals of potential biased processing of food information remains unclear. To address the nature of biased attention processing, we ask 1) how attention is biased toward two cardinal properties of food information, namely, healthiness and tastiness, even though the food information is irrelevant to the task at hand; and 2) whether and how such processing might be dependent on the demandingness of the central task (i.e., perceptual load). We measure EEG responses to infrequent visual food information embedded in streams of other visual objects, specifically, by using oddball fast periodic visual stimulation (FPVS), which is a variant of steady-state visual evoked potentials (SSVEP). The infrequent food objects are of four different combinations based on healthiness and tastiness: 1) high healthiness and high tastiness; 1) high healthiness and low tastiness; 3) low healthiness and high tastiness; and 4) low healthiness and low tastiness. The perceptual load of the central task is either low (detection of a certain color of letters) or high (detection of certain combinations of color and identity of letters). To evaluate the potential role of satiety, we measure FPVS responses to food oddballs in two different states: at least 4 hours after the previous meal; and within 1 hour of the last meal. Subjective satiety level is recorded prior to the experiment. We then ask how such biased processing might be linked to individual differences in: 1) external eating (measured by Dutch Eating Behavior Questionnaire, DEBQ); 2) impulsivity (measured by Barratt Impulsiveness Scale, BIS-11); 3) trait reward sensitivity (measured by the BIS/BAS scale); 4) BMI. Test–retest reliability will be assessed for the EEG FPVS task.

In a visual recognition masking experiment, a target stimulus to be identified is either preceded or followed by a second stimulus called a masking stimulus. The experiments described here provide estimates of both developmental and aging differences in visual backward masking under conditions which maximize interference in the central visual system. The results indicate that when no-mask recognition performance is at 100 percent, significant Age X Stimulus Onset Asynchronies interactions can be detected. However, the absence of this type of interaction when no-mask recognition performance is adjusted to the 70 percent level suggests that these interactions are caused by factors other than rate of processing differences. (Author/BW)