Visual Psychophysics

A comprehensive treatment of the skills and techniques needed for visual psychophysics, from basic tools to sophisticated data analysis. Vision is one of the most active areas in biomedical research, and visual psychophysical techniques are a foundational methodology for this research enterprise. Visual psychophysics, which studies the relationship between the physical world and human behavior, is a classical field of study that has widespread applications in modern vision science. Bridging the gap between theory and practice, this textbook provides a comprehensive treatment of visual psychophysics, teaching not only basic techniques but also sophisticated data analysis methodologies and theoretical approaches. It begins with practical information about setting up a vision lab and goes on to discuss the creation, manipulation, and display of visual images; timing and integration of displays with measurements of brain activities and other relevant techniques; experimental designs; estimation of behavioral functions; and examples of psychophysics in applied and clinical settings. The book's treatment of experimental designs presents the most commonly used psychophysical paradigms, theory-driven psychophysical experiments, and the analysis of these procedures in a signal-detection theory framework. The book discusses the theoretical underpinnings of data analysis and scientific interpretation, presenting data analysis techniques that include model fitting, model comparison, and a general framework for optimized adaptive testing methods. It includes many sample programs in Matlab with functions from Psychtoolbox, a free toolbox for real-time experimental control. Once students and researchers have mastered the material in this book, they will have the skills to apply visual psychophysics to cutting-edge vision science.

This volume on Visual Psychophysics documents the current status of research aimed toward understanding the intricacies of the visual mechanism and its laws of operation in intact human perceivers. As can be seen from the list of contributors, the problems of vision engage the interest and experimental ingenuity of investi gators from a variety of disciplines. Thus we find authors affiliated with depart ments of biology, medical and physiological physics, ophthalmology, physics, physiology and anatomy, psychology, laboratories of neurophysiology, medical clinics, schools of optometry, visual and othcr types of research institutes. A continuing interplay between psychophysical studies and physiological work is everywhere evident. As more information about the physiological basis of vision accumulates, and new studies and analyses of receptor photochemistry and the neurophysiology of retina and brain appear, psychophysical studies of the intact organism become more sharply focused, sometimes more complex, and often more specialized. Technological advances have increased the variety and precision of the stimulus controls, and advances in measurement techniques have reopened old problems and stimulated the investigation of new ones. In some cases, new concepts are being drawn in to help further our under standing of the laws by which the visual mechanism operates; in other cases, ideas enunciated long ago have been reevaluated, developed more fully, and reified in terms of converging evidence from both psychophysical experiments and unit recordings from visual cells.

Visual Psychophysics and Physiology: A Volume Dedicated to Lorrin Riggs illustrates a particular approach to the study of vision. It also celebrates Lorrin Riggs' retirement from formal teaching duties. During his teaching career Riggs advised and directed about fifty doctoral and postdoctoral students, many of whom wrote the chapters that make up this volume. The book is organized into six parts. Part 1 explains the approach to the study of vision, thus providing the philosophical theme for the chapters that follow. Part 2 on physiological mechanisms presents examples of comparative and physiological investigations. Part 3 on sensitivity and adaptation examines new research that bears directly upon the classical problems of visual psychophysics. Here, there is an initial concern with measurement, visual sensitivity, scaling, and adaptation. Part 4 discusses research on color vision while Part 5 on acuity, contrast, and movement considers some of the factors that contribute to these perceptions. Part 6 deals with applications of visual science to other disciplines. Specific examples are given that link visual research with ophthalmology, child development, and the investigation of cognitive variables such as meaning, activation, and so forth.

Written by a leader in the field, this book discusses the role of vision in reading. The author describes the influence of physical properties of text on reading performance and the implications for information processing in the visual pathways. He explores different forms of low vision that affect reading, text characteristics that optimize reading for those with low vision, principles underlying the legibility of text, and guidelines for displaying text. Special topics include the role of the magnocellular pathway in reading and dyslexia, Braille reading, and fonts for highway signs. An accompanying CD contains reprints of the seminal series of articles by Gordon E. Legge and colleagues published between 1985 and 2001.

This volume on Visual Psychophysics documents the current status of research aimed toward understanding the intricacies of the visual mechanism and its laws of operation in intact human perceivers. As can be seen from the list of contributors, the problems of vision engage the interest and experimental ingenuity of investi gators from a variety of disciplines. Thus we find authors affiliated with depart ments of biology, medical and physiological physics, ophthalmology, physics, physiology and anatomy, psychology, laboratories of neurophysiology, medical clinics, schools of optometry, visual and othcr types of research institutes. A continuing interplay between psychophysical studies and physiological work is everywhere evident. As more information about the physiological basis of vision accumulates, and new studies and analyses of receptor photochemistry and the neurophysiology of retina and brain appear, psychophysical studies of the intact organism become more sharply focused, sometimes more complex, and often more specialized. Technological advances have increased the variety and precision of the stimulus controls, and advances in measurement techniques have reopened old problems and stimulated the investigation of new ones. In some cases, new concepts are being drawn in to help further our under standing of the laws by which the visual mechanism operates; in other cases, ideas enunciated long ago have been reevaluated, developed more fully, and reified in terms of converging evidence from both psychophysical experiments and unit recordings from visual cells.

Psychophysics: A Practical Introduction, Second Edition, is the primary scientific tool for understanding how the physical world of colors, sounds, odors, movements, and shapes translates into the sensory world of sight, hearing, touch, taste, and smell; in other words, how matter translates into mind. This timely revision provides a unique introduction to the techniques for researching and understanding how the brain translates the external physical world to the internal world of sensation. The revision expands and refines coverage of the basic tools of psychophysics research and better integrates the theory with the supporting software. The new edition continues to be the only book to combine, in a single volume, the principles underlying the science of psychophysical measurement and the practical tools necessary to analyze data from psychophysical experiments. The book, written in a tutorial style, will appeal to new researchers as well as to seasoned veterans. This introduction to psychophysics research methods will be of interest to students, scholars and researchers within sensory neuroscience, vision research, behavioral neuroscience, and the cognitive sciences. Presents a large variety of analytical methods explained for the non-expert Provides a novel classification scheme for psychophysics experiments Includes a new software package for collecting and analyzing psychophysical data Disseminates the pros and cons of different psychophysical procedures Contains practical tips for designing psychophysical experiments

This volume on Visual Psychophysics documents the current status of research aimed toward understanding the intricacies of the visual mechanism and its laws of operation in intact human perceivers. As can be seen from the list of contributors, the problems of vision engage the interest and experimental ingenuity of investi gators from a variety of disciplines. Thus we find authors affiliated with depart ments of biology, medical and physiological physics, ophthalmology, physics, physiology and anatomy, psychology, laboratories of neurophysiology, medical clinics, schools of optometry, visual and othcr types of research institutes. A continuing interplay between psychophysical studies and physiological work is everywhere evident. As more information about the physiological basis of vision accumulates, and new studies and analyses of receptor photochemistry and the neurophysiology of retina and brain appear, psychophysical studies of the intact organism become more sharply focused, sometimes more complex, and often more specialized. Technological advances have increased the variety and precision of the stimulus controls, and advances in measurement techniques have reopened old problems and stimulated the investigation of new ones. In some cases, new concepts are being drawn in to help further our under standing of the laws by which the visual mechanism operates; in other cases, ideas enunciated long ago have been reevaluated, developed more fully, and reified in terms of converging evidence from both psychophysical experiments and unit recordings from visual cells.