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Tri 2 2016/2017

Tri 2 2016/2017

A series of experiments are described which were conducted to further refine experimental paradigms for the investigation of information processing skills relevant to pilot training. A series of tasks have been developed and studied which attempt to measure the individual's information processing capacity as well as his susceptibility to performance degradation resulting from the introduction of interfering stimuli. Data suggest performance on these tasks to be highly dependent on individual differences, therefore, making them good candidates for use as tools in the investigation of information processing skills in flying training. Implications for direct application to flying training research are discussed. (Author/DGC)

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

The first year of the grant was spent in setting up the laboratory, and in starting research on a number of different projects. All are concerned with the visual processing of information in the perception of objects. A series of experiments has explored the perception of conjunctions of features, attempting to determine what makes this difficult or easy. A new method (detection of apparent motion) was tested and a modification of feature-integration theory was developed to accommodate the new results. Other projects have been concerned with coding of features, finding evidence for modularity, testing the level of abstraction at which features (such as orientation) are coded, the different media which support the coding of shape, and the space in which they are represented (retinal or three-dimensional). Another project has probed the effects of perceptual learning with extended practice at detecting particular sets of targets; the results suggest that automatization in search is highly specific to the practiced task and has little effect on other perceptual tests. Six graduate students are at present, working on projects wholly or partly supported by the grant.

It is suggested that recent advances in the construction of artificial vision systems provide the beginnings of a framework for an information processing analysis of human visual perception. A review is made of some pertinent investigations which have appeared in the psychological literature, along with some of the salient and potentially useful theoretical concepts which have resulted from the attempts to build computer vision systems. An attempt is made to integrate these two sources of ideas to suggest some desirable structural and behavioral concepts which apply to both the natural and the artificial systems.

A simulated art history textbook reading assignment was designed to examine the effects of visual information on student learning and understanding. A sample of 234 students was taken from a population of freshman/sophomore English students in a large metropolitan community college district. In phase one of the study, students took the Group Embedded Figures Test (GEFT), which contained geometric figures embedded in a background. During phase two, students were randomly assigned to one of two different groups in which the treatments were two 1500-word expository prose passages. The difference between the two treatments was in the number of pictures; although the picture subject matter was identical, one treatment included additional close-up photographs and illustrations. Students were asked to visualize the pictures of vases that they had read about, then to draw each vase and write down every word recalled from the reading. Results suggest that when subjects are asked to recall pictures of single objects, most subjects can successfully execute in drawings a reasonable likeness of what they have seen and that subjects' performance is differentially reflected on the basis of both cognitive style and picture design factors. Eight figures depict study results. (Contains 27 references.) (AEF)

A simulated art history textbook reading assignment was designed to examine the effects of visual information on student learning and understanding. A sample of 234 students was taken from a population of freshman/sophomore English students in a large metropolitan community college district. In phase one of the study, students took the Group Embedded Figures Test (GEFT), which contained geometric figures embedded in a background. During phase two, students were randomly assigned to one of two different groups in which the treatments were two 1500-word expository prose passages. The difference between the two treatments was in the number of pictures; although the picture subject matter was identical, one treatment included additional close-up photographs and illustrations. Students were asked to visualize the pictures of vases that they had read about, then to draw each vase and write down every word recalled from the reading. Results suggest that when subjects are asked to recall pictures of single objects, most subjects can successfully execute in drawings a reasonable likeness of what they have seen and that subjects' performance is differentially reflected on the basis of both cognitive style and picture design factors. Eight figures depict study results. (Contains 27 references.) (AEF)

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.

The research carried out during the period of the grant continued several lines of investigation on the way in which sensory and high-level influences contribute to the control of smooth and saccadic eye movements and on the perceptual implications of eye movements. We: (1) provided the first clear evidence that symbolic cues determine the direction of anticipatory smooth eye movements, showing that adaptive models, based on algorithms that modify pursuit according to prior performance cannot work; (2) showed that saccades to spatially-extended targets are best understood by a serial model, with a selection stage followed by a spatial pooling mechanism; (3) showed that slow control is a velocity, not a position, corrective and (4) showed that saccades (not shifts of attention) are required for accurate perception of poorly- segregating textures. These results are all consistent with the view that sensory and cognitive influences combine at a relatively high level of processing to provide a single, coherent input to the oculomotor system. Kowler also edited a book, published by Elsevier, containing major reviews and theoretical treatments of eye movements, vision and cognition.

This collection of abstracts is part of a continuing series providing information on recent doctoral dissertations. The 28 titles deal with a variety of topics, including the following: (1) abled and disabled sixth grade readers' knowledge of story structure under three conditions, (2) the impact of typographical factors on the visual information processing of disabled readers, (3) alphabet sequencing by efficient and deficient oral readers, (4) the fear of failure/fear of success phenomenon in dyslexic adolescent students, (5) the effects of QR (Quieting Response) training on reading comprehension scores of junior high school remedial reading students, (6) the influence of reader interest and reader prior knowledge on the reading performance of fourth grade unskilled readers, (7) the impact of the Title I reading program on high school students' reading achievement, (8) the relationship between bibliotherapy and the self-esteem of junior high school remedial reading students, (9) the alleviation of learned helplessness in poor readers through modeled optimism and competency training, and (10) the listening-reading scores of average deficient readers. (MM)

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.

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.

The central goal of the project funded by the current grant is the understanding of how saccadic eye movements are used to accurately localize objects in space. Explaining accurate localization is a real problem because the objects we choose to look at are relatively large -- typically extending over several degrees of space -- but the saccadic eye movement must land at one place within the target. Our published research suggests that the computation requires a sequence of two stages: (1) voluntary attentional weighting of information in the visual display, and (2) automatic-spatial-pooling of the weighted formation (He and Kowler, 1989; 1991).

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)

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.

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.

Research carried out on several interrelated topics is described. These projects are all in the area of visual cognition, and focus on feature and object perception, models of selective attention, and the nature of visual routines such as curve tracing and subitizing. The major thrust of this endeavor has been to explore the nature of visual processes to determine the extent to which they are carried out in parallel or in series. (edc)

Includes bibliographies

Functional organization of visual fields

Functional organization of visual fields

Memory and Cognition : v.9, no.3, 1981, p. 301-307

Memory and Cognition : v.9, no.3, 1981, p. 301-307

Memory and Cognition : v.9, no.3, 1981, p. 301-307

NAS 1.55:3053 Digitized from IA1177307-03-0063 , IA1177307-03-0064 , IA1177307-03-0065 .

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.

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.

In the domain of motion perception, the implementation of a new pedestal paradigm and some critical subsidiary paradigms (interocular displays, stimulus superpositions with varying phases and directions, alternating-feature stimuli, and attentional manipulations) enabled the measurement in isolation of the spatial and temporal characteristics of the three main human motion perception mechanisms (the so-called first-, second, and third-order systems). The first- and second-order systems, known previously, were now shown to exist in duplicate, having a primarily left eye and a primarily right eye computational branch. Additionally, a purely binocular (third-order) motion mechanism was discovered and measured.

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.

Chapter 1 of this report, "Introduction and General Recommendations for Eye-Movement Research and Instrumentation," discusses research priorities; encouraging and supporting theories, models, or simulations of information processing; and improved instrumentation in the field of visual information processing. Chapter 2, "Summary of Specific Recommendations," presents specific recommendations for the following four clusters: (1) reading texts, pictures, and other graphic displays; (2) processing television displays; (3) eye-movement research; and (4) instrumentation and instrumentalities. Chapter 3, "Specific Recommendations for Directions in Eye-Movement Research," recommends eye-movement research that explores the moment-to-moment information intake and processing mechanisms in the encounter of an individual with text, pictures, and other static graphic display; suggests research that explores the intake and processing of dynamic visual information as it is received from television; and argues the general value of eye movement research. Chapter 4, "Instrumentation and Instrumentalities," has four parts relating to the following areas: research, management, review, and support; instrumentation development; facilities dissemination and establishment; and priorities. (WR)

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.

One of a series of investigations on the Project on an Information Memory Model, the purpose of this study was to determine the amount and kind of visual information processed and stored in the memory of children using different modalities of observation. Children, aged 5, 9 and 13 years, were randomly assigned to one of three treatment groups. Two of the treatment groups individually viewed silently (N=21 per age level) or vocally (N=21 per age level) a projected 35mm slide of a living room. The third group (N-45 per age level) viewed the picture display in groups of three and verbally exchanged enumerations of items. Five minutes were allowed for viewing the slide. The subjects then verbally recalled the viewing experience and their recollections were tape recorded. As the age of the subjects increased, the numbe of picture item messages and variety or number of different picture items verbalized in the enumeration phase of the experiment also increased. A message processor algorithm for forecasting cognitions of verbal and nonverbal modalities was used with a prediction error of less than two percent. An item dimension algorithm for forecasting cognitions was developed to measure the M unit structure of memory pathways. The finding was that chronological age was related to M units of variations of learning and recall tasks. (Author/PEB)

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 project concerned the discovery and description of basic mechanisms of human visual motion and texture perception. Motion and texture are critical inputs to visual perception. Basic mechanisms of motion are of particular interest because they are perhaps the primary substrate for perceptual recovery of 3D depth structures and orientation in space, they are critical for detecting new objects and events in the environment, as well as playing an important role in 2D perception. Motion and texture are considered together here because the problem of discriminating velocity in a one- dimensional motion stimulus is formally equivalent to the problem of discriminating orientation in a texture stimulus: the t dimension of the motion stimulus becomes the y dimension of the texture stimulus.

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 processing of televised information was compared among 85 Japanese and 111 American boys and girls at the kindergarten and 4th-grade levels. The literatures on cognition and learning indicate that language and child rearing factors are more conducive to the development of iconic processing skills in Japanese children than in American children, a phenomenon which increases with age. The reverse pattern is found for verbal processing skills. It was predicted that after viewing a television program without narration or dialogue, Japanese children's amount and concentration of visual attention and comprehension would be higher than that of American children, particularly at the 4th-grade level. Results confirmed the predictions for visual attention, suggesting that different television processing strategies were employed. Contrary to the predictions, American children scored higher than Japanese children on the comprehension test, perhaps because of the cultural differences in expectations about the testing procedure. The results are discussed in the context of processing differences. Alternative explanations for the findings are explored, and directions for future research are suggested. Appended are seven pages of references, seven tables and two figures. (Author/RH)

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)

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.

A recent advance by B. F. Logan in the theory of one octave bandpass signals may throw new light on spatial-frequency-tuned channels in early visual information processing. (Author)

A recent advance by B. F. Logan in the theory of one octave bandpass signals may throw new light on spatial-frequency-tuned channels in early visual information processing. (Author)

Includes bibliographical references (pages 369-386) and index

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 research supported by my grant from AFOSR this year completed some of the projects outlined in the first annual report and initiated some new ones. The focus remained on the visual processing of features and objects, the role of spatial attention and the representation of complex visual patterns in perception and memory. Studies of visual search explored the coding of features at potentially more abstract levels than simple luminance filters: Among the features studied were orientation (for lines, dot pairs and edges), orientation and size (for shapes whose boundaries were defined by discontinuities of texture, motion and depth), and illusory contours. Another series of experiments tested the mechanisms underlying the coding of feature conjunctions, using evidence from search latencies and illusory conjunction errors. The results led to a proposed revision of my earlier feature integration theory. Two other studies looked at memory for visual patterns. One studied the effects of prolonged practice (thousands of trials) on the coding of visual patterns. At the other extreme, an experiment explored the effects on memory just one to five presentations of similar patterns. In both cases, we found striking specificity in the coding of these meaningless shapes and in their effects on subjects' later experiences with the same stimuli. Patterned conjunctions of lines, once formed, appear to persist in visual memory and to facilitate their later re- perception provided that the same task and context are also reinstated. Keywords: Attention.

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.

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)