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The Ecological Revolution: The Senses Considered as Perceptual Systems, 50 Years Later - Part 2

ABSTRACT This editorial presents the second of a 2-part special issue honoring the publication of James J. Gibsons 1966 book, The Senses Considered as Perceptual Systems. As was pointed out by several reviews of this book written just after its publication (i.e., between 1967 and 1969), Gibsons 1966 book represents a revolution not only for the psychological science but also for domains beyond that of psychology. This second part of the special issue is composed of 5 theoretical contributions that represent, in addition to the 4 pieces previously published in the first part, the far-reaching influence of Gibsons ecological revolution.

The Senses Considered as Perceptual Systems: The Revolutionary Ideas of Gibson's 1966 Book, 50 Years Later - Part 1

ABSTRACT This editorial introduces the first part of a 2-part special issue of Ecological Psychology dedicated to James J. Gibsons 1966 book, The Senses Considered as Perceptual Systems, which presents many revolutionary ideas that are important not only for the study of perception but also for the science of psychology in general including the rejection of the mechanistic and dualistic stimulus-response formula (cf. Dewey, 1896), the rejection of sensation-based theories of perception, and the insistence that the unit of investigation and explanation is the mutual relation between people and other animals and their environments.

Invariants and Information Pickup in The Senses Considered as Perceptual Systems: Implications for the Experimental Analysis of Behavior

ABSTRACT Although Gibson focused his agenda on the study of perception and Skinner on learning as contingencies of reinforcement, they shared a nonrepresentational approach. We propose that the ecological concept of invariants developed in Gibsons book The Senses Considered as Perceptual Systems (1966) could underlie Skinners notion of contingencies of reinforcement as environmental opportunities for behaving. The proposal is divided in 3 parts: the concept of stimulus for perception, the role of the notion of invariants in the operant contingency, and the information for perception and behavior. We conclude that approximating contingencies of reinforcement as instances of environmental invariants can be fruitful for studying a number of phenomena within the context of operant conditioning.

Discrete and continuous stimulus control in the A-not-B sandbox task.

In behavior-analytic studies of generalization, stimulus control appears to be discrete rather than continuous: after two behavior patterns R1 and R2 are trained in the presence of stimuli A and B, respectively, tests of intermediate stimuli evoke R1 and R2 in varying proportions rather than an actual mix of R1 and R2. By contrast, theories and data from developmental psychology suggest that spatial searches in the A-not-B sandbox task may be continuous: after burying an object at position A and then at position B, children may search the sand surface at positions that are actually intermediate between A and B. The published evidence so far has been ambiguous, however, because researchers typically report group means rather than response distributions, and group means intermediate between A and B might be statistical artefacts of averaging across subjects. Here we report two A-not-B sandbox studies designed to address this issue. In Experiment 1, which employed a purely motor A-not-B procedure, stimulus control was found to be continuous. In Experiment 2, which used a purely observational A-not-B procedure, stimulus control was basically discrete but also exhibited continuous aspects. These findings are discussed in relation to cognitive and behavior-analytic approaches to stimulus control.