Psychophysics

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

Psychophysical theory exists in two distinct forms -- one ascribes the explanation of phenomena and empirical laws to sensory processes. Context effects arising through the use of particular methods are an unwanted nuisance whose influence must be eliminated so that one isolates the "true" sensory scale. The other considers psychophysics only in terms of cognitive variables such as the judgment strategies induced by instructions and response biases. Sensory factors play a minor role in cognitive approaches. This work admits the validity of both forms of theory by arguing that the same empirical phenomena should be conceptualized in two alternative, apparently contradictory, ways. This acceptance of opposites is necessary because some empirical phenomena are best explained in terms of sensory processes, while others are best ascribed to central causes. The complementarity theory stresses the "mutually completing" nature of two distinct models. The first assigns importance to populations of sensory neurons acting in the aggregate and is formulated to deal with sensory effects. The second assigns importance to judgment uncertainty and to the subject strategies induced by experimental procedures. This model is formulated to explain context effects. Throughout the text, the exposition is interlaced with mathematics, graphs, and computer simulations designed to reveal the complementary nature of psychophysical explanations.

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.

Psychophysics: A Practical Application is a single-volume text that covers the rudimentary principles of psychophysical methods and the practical tools that are important for processing data from psychophysical experiments and tests. It makes complicated concepts and procedures understandable for beginners and non-experts in psychophysics. The book includes a wide array of analytical techniques, such as novel classification schemes for psychophysics experiments; new software packages for collecting and processing psychophysical data; practical tips for designing psychophysical experiments; and the advantages and disadvantages of the different psychophysical methods. The first chapters of the book present the fundamental concepts and terminology of psychophysics, and they familiarize readers with available psychophysical techniques. The remaining chapters discuss a series of topics, such as psychometric functions, adaptive procedures, signal detection measures, scaling methods, and statistical model comparisons. The book serves as an invaluable source of information about psychophysics for researchers and optometrists, as well as for psychology and neuroscience students, on both the graduate and undergraduate level. Large variety of analytical methods explained for the non-expert Novel classification scheme for psychophysics experiments New software package for collecting and analyzing psychophysical data Pros and cons of different psychophysical procedures Practical tips for designing psychophysical experiments

Psychophysics is a lively account by one of experimental psychology's seminal figures of his lifelong scientific quest for general laws governing human behavior. It is a landmark work that captures the fundamental themes of Stevens's experimental research and his vision of what psycho-physics and psychology are and can be. The context of this modern classic is detailed by Lawrence Marks's pungent and highly revealing introduction. The search for a general psychophysical law—a mathematical equation relating sensation to stimulus—pervades this work, first published in 1975. Stevens covers methods of measuring human psychophysical behavior: magnitude estimation, magnitude production, and cross-modality matching are used to examine sensory mechanisms, perceptual processes, and social consensus. The wisdom in this volume lies in its exposition of an approach that can apply generally to the study of human behavior