Sensory studies, or when physics was psychophysics: Ernst Mach and physics between physiology and psychology, 1860-71.

This paper highlights the significance of sensory studies and psychophysical investigations of the relations between psychic and physical phenomena for our understanding of the development of the physics discipline, by examining aspects of research on sense perception, physiology, esthetics, and psychology in the work of Gustav Theodor Fechner, Hermann von Helmholtz, Wilhelm Wundt, and Ernst Mach between 1860 and 1871. It complements previous approaches oriented around research on vision, Fechner's psychophysics, or the founding of experimental psychology, by charting Mach's engagement with psychophysical experiments in particular. Examining Mach's study of the senses and esthetics, his changing attitudes toward the mechanical worldview and atomism, and his articulation of comparative understandings of sensual, geometrical, and physical spaces helps set Mach's emerging epistemological views in the context of his teaching and research. Mach complemented an analytic strategy focused on parallel psychic and physical dimensions of sensation, with a synthetic comparative approach - building analogies between the retina, the individual, and social life, and moving between abstract and sensual spaces. An examination of the broadly based critique that Mach articulated in his 1871 lecture on the conservation of work shows how his historical approach helped Mach cast what he now saw as a narrowly limiting emphasis on mechanics as a phase yet to be overcome.

The forgotten history of signal detection theory.

Signal detection theory is one of psychology's most well-known and influential theoretical frameworks. However, the conceptual hurdles that had to be overcome before the theory could finally emerge in its modern form in the early 1950s seem to have been largely forgotten. Here, I trace the origins of signal detection theory, beginning with Fechner's (1860/1966) Elements of Psychophysics. Over and above the Gaussian-based mathematical framework conceived by Fechner in 1860, nearly a century would pass before psychophysicists finally realized in 1953 that the distribution of sensations generated by neural noise falls above, not below, the threshold of conscious awareness. An extensive body of single-unit recording and neuroimaging research conducted since then supports the idea that sensory noise yields genuinely felt conscious sensations even in the complete absence of stimulation. That hard-to-come-by insight in 1953 led immediately to the notion of a movable decision criterion and to the methodology of receiver operating characteristic (ROC) analysis. Over the ensuing years, signal detection theory and ROC analysis have had an enormous impact on basic and applied science alike. Yet, in some quarters of our field, that fact appears to be virtually unknown. By tracing both its fascinating origins and its phenomenal impact, I hope to illustrate why no area of experimental psychology should ever be oblivious to signal detection theory. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

A Conversation with Jacob Nachmias.

We are sad to report that Professor Jacob (Jack) Nachmias passed away on March 2, 2019. Nachmias was born in Athens, Greece, on June 9, 1928. To escape the Nazis, he and his family came to the United States in 1939. He received his undergraduate degree from Cornell University and then an MA from Swarthmore College, where he worked with Hans Wallach and Wolfgang Kohler; his PhD in Psychology was from Harvard University. Nachmias spent the majority of his career as a Professor of Psychology at the University of Pennsylvania. He made fundamental contributions to our understanding of vision, most notably through the study of eye movements, the development of signal detection theory and forced-choice psychophysical methods, and the psychophysical characterization of spatial-frequency-selective visual channels. Nachmias' work was recognized by his election to the National Academy of Sciences and receipt of the Optical Society's Tillyer Award.

Sustained Attention to Science: A Tribute to the Life and Scholarship of Joel Warm.

OBJECTIVE: To provide an evaluative synthesis of the life and scientific contributions of the late Joel Warm. BACKGROUND: As the doyen of vigilance research, Joel Warm expanded our understanding and horizons concerning this critical response capacity. However, he also made widespread and profound contributions to many other areas of perception and applied psychology, as we elucidate here. METHOD: Using archival sources, personal histories, and analysis of extant literature documenting Warm's own productivity, we articulate his life in science. RESULTS: Our synthesis illustrates the continued, broad, influential, and expanding impact that one individual can exert on diverse fields of study. Whole bodies of understanding of human behavior have been illuminated by his exemplary career. APPLICATION: By understanding his path to success in applied experimental psychology, we anticipate that others will be motivated, inspired, and guided to replicate and even outstrip a lifetime of such seminal and influential contributions. The presence of individuals such as Warm serves as a primary motive in enhancing Humans Factors/Ergonomics Science.

Charles "Erik" Eriksen (1923-2018).

A towering figure in experimental psychology, Charles W. Eriksen, passed away in February this year. "Erik" made extensive original and lasting contributions to both research methods and theories in several areas of psychology, especially involving visual information processing. His research exhibited consistent concerns with experimental methods for distinguishing among alternative explanations and distinguishing perception from behavior. Erik pioneered many research methods now in common use-including converging operations, visual search, rapid serial presentations, the stop-signal paradigm, temporal integration in form perception, spatial cues for guiding selective attention, and the flankers task. He also introduced and tested many theories of selective attention. Erik was the founding editor of Perception & Psychophysics, and served for 23 years as its principal editor. An impressive and unforgettable person, Erik was a compelling personification of "the greatest generation."

Award for Distinguished Scientific Early Career Contributions to Psychology: Greg Hajcak.

APA's Awards for Distinguished Scientific Early Career Contributions to Psychology recognize psychologists who have demonstrated excellence early in their careers. One of the 2016 award winners is Greg Hajcak, whose "groundbreaking contributions applying psychophysiological methods to the affective neuroscience of anxiety, depression, psychosis, and related traits" and whose work "has identified promising risk biomarkers and intervention targets and has illuminated the development of, and mechanisms associated with, these disorders." Hajcak's award citation, biography, and bibliography are presented here. (PsycINFO Database Record

Why the "stimulus-error" did not go away.

Psychologists in the early years of the discipline were much concerned with the stimulus-error. Roughly, this is the problem encountered in introspective experiments when subjects are liable to frame their perceptual reports in terms of what they know of the stimulus, instead of just drawing on their perceptual experiences as they are supposedly felt. "Introspectionist" psychologist E. B. Titchener and his student E. G. Boring both argued in the early 20th century that the stimulus-error is a serious methodological pit-fall. While many of the theoretical suppositions motivating Titchener and Boring have been unfashionable since the rise of behaviourism, the stimulus-error brings our attention to one matter of perennial importance to psychophysics and the psychology of perception. This is the fact that subjects are liable to give different kinds of perceptual reports in response to the same stimulus. I discuss attempts to control for variable reports in recent experimental work on colour and lightness constancy, and the disputes that have arisen over which kinds of reports are legitimate. Some contemporary psychologists do warn us against a stimulus-error, even though they do not use this terminology. I argue that concern over the stimulus-error is diagnostic of psychologists' deep theoretical commitments, such as their conception of sensation, or their demarcation of perception from cognition. I conclude by discussing the relevance of this debate to current philosophy of perception.

Numerical cognition: Adding it up.

In this article, I provide a historical overview of the field of numerical cognition. I first situate the evolution and development of this field in the more general context of the cognitive revolution, which started in the mid-1950s. I then discuss the genesis of numerical cognition from 6 areas: psychophysics, information processing, neuropsychology, mathematics education, psychometrics, and cognitive development. This history is personal: I discuss some of my own work over the last 30 years and describe how each of the authors of the articles in this collection originally connected with the field. One important goal of the article is to highlight the major findings, both for experts and for those who are less familiar with research on numerical processing. In sum, I sketch a context within which to appreciate the neural, computational, and behavioural work that the other 4 authors summarise in their articles in this special section.

Galileo's Dagger.

Galileo found that fine lines on a balance scale dazzled his eyes and were unreadable. So he used a grid of fine wires instead and ran his dagger across it, counting the number of auditory clicks. This is the first known experiment on sensory substitution.

Yarbus's Conceptions on the General Mechanisms of Color Perception.

In the last series of papers published during 1975 to 1980, Alfred Yarbus tried to formulate general conceptions concerning the basic principles of retinal image processing in the human visual system. The original ideas of Yarbus were based on the results of his numerous and various experiments carried out with extraordinary inventiveness and great skill. Being concentrated primarily on the problems of color vision, Alfred Yarbus dreamed of elaborating a comprehensive model that would simulate visual information processing at the monocular precognitive level in the visual system of humans with normal trichromatic color perception. In this article, the most important of Yarbus' experimental paradigms, findings, statements, and conclusions are systematized and considered in relation to the classical theories of color perception and, in particular, fundamental theses of the Nyberg school. The perceptual model developed by Alfred Yarbus remained incomplete. Nevertheless, it is already evident that some intrinsic contradictions make it inadequate in terms of comprehensive modeling. However, certain partial advantages deserve more thorough appreciation and further investigation.

A Bayesian perspective on magnitude estimation.

Our representation of the physical world requires judgments of magnitudes, such as loudness, distance, or time. Interestingly, magnitude estimates are often not veridical but subject to characteristic biases. These biases are strikingly similar across different sensory modalities, suggesting common processing mechanisms that are shared by different sensory systems. However, the search for universal neurobiological principles of magnitude judgments requires guidance by formal theories. Here, we discuss a unifying Bayesian framework for understanding biases in magnitude estimation. This Bayesian perspective enables a re-interpretation of a range of established psychophysical findings, reconciles seemingly incompatible classical views on magnitude estimation, and can guide future investigations of magnitude estimation and its neurobiological mechanisms in health and in psychiatric diseases, such as schizophrenia.

Schumann's wheel tachistoscope: its reconstruction and its operation.

In the fall and winter of 1910, Max Wertheimer (1880-1943) performed his famous experiments on perceived motion, published in 1912. Besides slider experiments he mainly used a wheel tachistoscope developed by Friedrich Schumann (1863-1940) at the end of the 19th century. The Adolf-Wuerth-Center for the History of Psychology has several wheel tachistoscopes in its collection of instruments. Their provenance can be traced back to the Institute of Psychology of the University of Frankfurt and the University of Zurich. It is very plausible that Wertheimer, who performed his experiments at the Frankfurt Institute, used one of them. But the wheel tachistoscope alone is not sufficient to reconstruct Wertheimer's original experiments. As always, the devil is in the details. Wertheimer's descriptions of the necessary accessories, a prism, a viewing device, and an electric motor to move the wheel, are rather sparse. This article describes the results of a search for traces in the literature, in archives, and in literary depositories to shed some light on Wertheimer's experimental equipment. As a result, it was possible to reconstruct the entire apparatus and to obtain the same optical impressions with the reconstructed devices as Wertheimer's observers reported. In addition, one of his results was replicated with new participants exactly 100 years after its first publication.

Receptive fields of visual neurons: the early years.

This paper traces the history of the visual receptive field (RF) from Hartline to Hubel and Wiesel. Hartline (1938, 1940) found that an isolated optic nerve fiber in the frog could be excited by light falling on a small circular area of the retina. He called this area the RF, using a term first introduced by Sherrington (1906) in the tactile domain. In 1953 Kuffler discovered the antagonistic center-surround organization of cat RFs, and Barlow, Fitzhugh, and Kuffler (1957) extended this work to stimulus size and state of adaptation. Shortly thereafter, Lettvin and colleagues (1959) in an iconic paper asked "what the frog's eye tells the frog's brain". Meanwhile, Jung and colleagues (1952-1973) searched for the perceptual correlates of neuronal responses, and Jung and Spillmann (1970) proposed the term perceptive field (PF) as a psychophysical correlate of the RF. The Westheimer function (1967) enabled psychophysical measurements of the PF center and surround in human and monkey, which correlated closely with the underlying RF organization. The sixties and seventies were marked by rapid progress in RF research. Hubel and Wiesel (1959-1974), recording from neurons in the visual cortex of the cat and monkey, found elongated RFs selective for the shape, orientation, and position of the stimulus, as well as for movement direction and ocularity. These findings prompted the emergence in visual psychophysics of the concept of feature detectors selective for lines, bars, and edges, and contributed to a model of the RF in terms of difference of Gaussians (DOG) and Fourier channels. The distinction between simple, complex, and hypercomplex neurons followed. Although RF size increases towards the peripheral retina, its cortical representation remains constant due to the reciprocal relationship with the cortical magnification factor (M). This constitutes a uniform yardstick for M-scaled stimuli across the retina. Developmental studies have shown that RF properties are not fixed. RFs possess their full response inventory already at birth, but require the interaction with appropriate stimuli within a critical time window for refinement and consolidation. Taken together these findings paved the way for a better understanding of how objective properties of the external world are encoded to become subjective properties of the subjective, perceptual world.

Psychophysical factors that have been applied to clinical perimetry.

Perimetry is the most common clinical diagnostic test procedure for evaluating the status of peripheral visual function in the management of ocular and neurologic diseases. This procedure has an extended history, and its design, implementation and interpretation is dependent on many principles that have been developed through visual psychophysical studies of target size, target duration, background adaptation level, chromatic characteristics and other stimulus properties (see Greve, 1973; Johnson, 1994, chap. 17, 1996, 2008, 2010, chap. 23; Johnson & Keltner, 1998, chap. 7; Johnson & Sample, 2002, chap. 22; Johnson & Wall, 2011, chap. 35; Wall & Johnson, 2005, chap. 2 for reviews). This paper will provide a general overview of the history of perimetry, selection of stimulus parameters, development of test strategies, clinical testing conditions, new procedures and approaches to perimetry, experimental design, analysis and interpretation methods, hypothesis testing, prediction and forecasting procedures, and other related topics. It is somewhat paradoxical that although there have been major advances in all of these areas that have significantly enhanced the utility and value of this clinical diagnostic test, the fundamental methodology has remained mostly unchanged for thousands of years. It is hoped that this overview will be of assistance to investigators and clinicians who wish to use or modify this diagnostic procedure for their ongoing career activities.