We explore experimental methods used to study the phenomena of perceptual organization, first studied by the Gestalt psychologists. We describe an application of traditional psychophysics to perceptual organization and offer alternative methods. Among these, we distinguish two approaches that use multistable stimuli: (1) phenomenological psychophysics, in which the observer's response is assumed to accurately and directly reflect perceptual experience; and (2) the interference paradigm, in which an observer's response is evaluated as correct or incorrect because it pertains to a corrigible (...) task, but does not directly reflect the observer's experience. We show that phenomenological psychophysics can yield valuable information about perceptual organization and lends itself to the development of quantitative theory. We discuss some criticisms of the method and argue that the two approaches that use multistable stimuli are complementary. We also compare each of the approaches with traditional psychophysics. We conclude that the several methods are convergent. (shrink)
In Fechner's psychophysics, the 'mental' and the 'physical' were conceived as two phenomenal domains, connected by functional relations, not as two ontologically different realms. We follow the path from Fechner's foundational ideas and Mach's radical programme of a unitary science to later approaches to primary, psychophysically neutral experience (phenomenology, protophysics). We propose an 'integral psychophysics' as a mathematical study of law-like, invariant structures of primary experience. This approach is illustrated by a reinterpretation of psychophysical experiments in terms of perceptual situations (...) involving a constructed apparatus and an instructed subject. The problematic notion of 'measurement of sensation' is thus eliminated: 'sensations' are merely indices for classes of perceptually equivalent configurations (states of the apparatus) specified by the instruction. The locus of the measured is in the inter-subjectively shared, communicable world—not inside the subject's mind. Finally we discuss the role of integral psychophysics as a scientia prima , logically and methodically preceding physics and psychology. (shrink)
In past and modern psychophysics there are several unresolved methodological and philosophical problems of human and animal perception, including the outstanding question of the relational basis of whole psychophysics. Here the main issue is discussed: if, and to what extent, there are viable bridges between the traditional “gestalt” oriented approaches and the modern perceptual-cognitive perspectives in psychophysics. Thereby the key concept of psychological “frame of reference” is presented by pointing to Hermann Ebbinghaus' geometric-optical illusions, on the one hand, and Max (...) Wertheimer's treatment of the traditional transposition phenomenon, on the other hand. A much-needed theoretical reorientation of future research may help to overcome the philosophical narrowness of present-day human and comparative psychophysics. (shrink)
Since the founding of psychophysics in the latter half of the nineteenth century, controversy has raged over the subject matter of psychophysical laws. Originally, Fechner characterized psycho physics as the science describing the relation between physical magnitudes and the sensations these magnitudes produce in us. Today many psycho-physicists would deny that sensation is or could be a topic of psycho-physical investigation. I consider Savage's (1970) influential objections to the possibility of such an investigation and argue that they depend upon (i) (...) holding psychophysics to higher standards than those to which we hold other sciences; and (ii) misrepresenting Fechner's stated goals for psychophysics. (shrink)
Imagery has played an important, albeit controversial, role in the study of memory psychophysics. In this commentary we critically examine the available data bearing on whether pictorial based depictions of remembered perceptual events are activated and scanned in each of a number of different psychophysical tasks.
Due to the wide array of phenomena that are of interest to them, psychologists offer highly diverse and heterogeneous types of explanations. Initially, this suggests that the question "What is psychological explanation?" has no single answer. To provide appreciation of this diversity, we begin by noting some of the more common types of explanations that psychologists provide, with particular focus on classical examples of explanations advanced in three different areas of psychology: psychophysics, physiological psychology, and information-processing psychology. To analyze what (...) is involved in these types of explanations, we consider the ways in which law-like representations of regularities and representations of mechanisms factor in psychological explanations. This consideration directs us to certain fundamental questions, e.g., "To what extent are laws necessary for psychological explanations?" and "What do psychologists have in mind when they appeal to mechanisms in explanation?" In answering such questions, it appears that laws do play important roles in psychological explanations, although most explanations in psychology appeal to accounts of mechanisms. Consequently, we provide a unifying account of what psychological explanation is. (shrink)
I survey some of the connections between the metaphysics of the relation between mind and matter, and quantum theory’s measurement problem. After discussing the metaphysics, especially the correct formulation of physicalism, I argue that two state-reduction approaches to quantum theory’s measurement problem hold some surprises for philosophers’ discussions of physicalism. Though both approaches are compatible with physicalism, they involve a very different conception of the physical, and of how the physical underpins the mental, from what most philosophers expect. And one (...) approach exemplifies a a problem in the definition of physicalism which the metaphysical literature has discussed only in the abstract. A version of the paper has appeared in Consciousness and Human Identity, ed. John Cornwell, OUP 1998. (shrink)
In the present paper the relation between objective and subjective time is studied from a neutral non-dualist perspective Adoption of the relational concept of time leads to fundamental problems of time measurement of the uniformity of time measures, and of a native measure of duration in subjective experience. Experimental data on discrimination and reproduction of time intervals are reviewed and relevant models of internal time representations are discussed. Special attention is given to the 'dual klepsydra model' (DKM)and to the outstanding (...) properties of the reproduction func- tion yielded by the DKM Time scales generated by a DKM-based reproduction mechanisms are studied It is shown that such 'klepsydraic clocks' generate time measures which are non-uniform with respect to objective time yet internally consistent within an ensemble of such clocks and in this sense 'quasi-uniform' . Competing concepts of subjective time and modeling principles of internal time representation are briefly discussed Some interesting parallels be- tween our psychophysical approach and E.A. Milne's treatment of the problem of uniform time are drawn in the Appendix. (shrink)
Advances in neuroscience implicate reentrant signaling as the predominant form of communication between brain areas. This principle was used in a series of masking experiments that defy explanation by feed-forward theories. The masking occurs when a brief display of target plus mask is continued with the mask alone. Two masking processes were found: an early process affected by physical factors such as adapting luminance and a later process affected by attentional factors such as set size. This later process is called (...) masking by object substitution, because it occurs whenever there is a mismatch between the reentrant visual representation and the ongoing lower level activity. Iterative reentrant processing was formalized in a computational model that provides an excellent fit to the data. The model provides a more comprehensive account of all forms of visual masking than do the long-held feed-forward views based on inhibitory contour interactions. (shrink)
Additional evidence is presented concerning the anisotropy between vertical and horizontal encoding, which emerges from studies of human perception and cognition of space in plane mirror reflections. Moreover, it is suggested that the non-metric characteristic of polarization is not limited to the vertical dimension.
In contrast to Lockhead's view it is argued that psychology as a genuine science must not be based on other sciences and that psychological measurements have to be validated inside psychology. It is pointed out that psychological scalings, unaffected by judgment contexts, can be obtained if the experimental setting is compatible with everyday situations.
Physicalism in philosophy of mind is the doctrine that mental states and processes, if they are something, are physical states and processes. Notoriously, Frank Jackson has attacked physicalism with the knowledge argument. This paper does not consider whether the knowledge argument is successful. Instead, the author argues that the ability reply to the knowledge argument fails. The central assumption of this objection is that Mary, by having colour experiences, acquires a set of abilities rather than new beliefs as required by (...) the knowledge argument. Against the ability reply, it is maintained that Mary on her release acquires new beliefs about objects looking the same colour. As a preliminary, it is shown, against an important criticism of the knowledge argument, that we can make sense of what Mary knows about colour experience when in the black-and-white laboratory. (shrink)
A consideration of Mach's elements, his philosophy of neutral monism, and philosophy of physics, especially space and time, much of it based on unpublished writings from the Nachlass and other original sources. The historical connection between Mach and logical positivism is shown to be superficial at best, and Mach's elements are shown to be mind independent natural qualities (world-elements) with dynamic force, not limited to human sensations.
Argues that there can be interaction without breaking physical laws: e.g. by basic psychic forces, or by varying physical constants, or especially by arranging fractal trees of physical causation leading to behavior.
During the 'sixties and 'seventies, Hilary Putnam, Jerry Fodor, and Richard Boyd, among others, developed a type of materialism that eschews reductionist claims.1 In this view, explana- tions, natural kinds, and properties in psychology do not reduce to counterparts in more basic sciences, such as neurophysiology or physics. Nevertheless, all token psychological entities-- states, processes, and faculties--are wholly constituted of physical entities, ultimately out of entities over which microphysics quantifies. This view quickly became the standard position in philosophy of mind, (...) and reductionism fell out of favor. Recently, however, reductionism has been experiencing a rebirth, and many have suggested that the non-reductive approach was accepted too quickly and too uncritically. In this paper, we attempt to provide a more thorough account of the anti-reductionist position, and, in the process, to defend it against its recent critics. (shrink)