Behavioral contrast without response-rate reduction1

Perceptual contrast and response assimilation in sequential categorization without feedback

Sequential categorization of perceptual stimuli typically shows contrast from one trial to the next. Using familiar categories of animals and faces, contrast effects were dissociated from assimilation effects. Two independent main effects were observed: contrast to the preceding stimulus, and assimilation to the previous response. It is argued that contrast and assimilation may reflect differen...

Behavioral contrast in competitive and noncompetitive environments.

Three experiments examined the effects of opportunities for an alternative response (drinking) on positive behavioral contrast of rats' food-reinforced bar pressing. In both Experiments 1 and 2 the baseline multiple variable-interval schedules were rich (variable interval 10-s), and contrast was examined both with and without a water bottle present. In Experiment 1, the rats were not water depr...

Behavioral Contrast in a Group Foraging Paradigm

Behavioral Response Study

This is the report of the first behavioral response study to be carried out on beaked and pilot whales in which these animals were exposed to carefully measured doses of underwater sound while their responses were being measured. The study is seen as the first step in a series of similar experiments that are designed to safely identify the behavioral mechanisms that may be involved in the causa...

Contrast discrimination with and without spatial uncertainty

The main purpose of these experiments was to examine in detail how successfully the uncertainty reduction explanation accounts for the effects of spatial cues in a temporal forced-choice contrast discrimination task in which any one of four well-separated Gabor patches is incremented. In preliminary experiments, it was shown that in the absence of uncorrelated contrast jitter, observers could u...