ABSTRACT
The present research investigates the mental processes involved in inducing continuous stimulus-response relations. A simple perceptual-motor learning task was used in which subjects learned to produce a continuous variable (response duration) accurately for values chosen from another continuous dimension (stimulus length). Subjects were trained on several “practice” pairs, for which they received feedback about the correct responses. Trials involving practice pairs were intermixed with trials involving “transfer” pairs, for which no feedback was given. The correct responses and stimuli were related by simple mathematical functions: a power (Experiment 1); a logarithmic (Experiment 2); and a linear function with a positive intercept (Experiment 3). Experiment 1 demonstrated that people can learn a power function rapidly and use it to perform as well for transfer pairs as for practice pairs. Experiments 2 and 3 revealed a systematic pattern of bias during early learning, consistent with the hypothesis that people have a predisposition toward inducing a power function. However, the biases decreased in magnitude with practice.
We propose an account for induction of continuous stimulus-response relations called the “adaptive-regression” model. According to it, people are initially biased to induce a power function, but the bias is gradually weakened through experience, so that other stimulus-response relations can be learned with sufficient practice. The present results support the adaptive-regression model.
