How do children learn to communicate, and what do they learn? Traditionally, most theories have taken an associative, compositional approach to these questions, supposing children acquire an inventory of form-meaning associations, and procedures for composing / decomposing them; into / from messages in production and comprehension. This paper…

Interleaving examples of to-be-learned categories, rather than blocking examples by category, frequently enhances category induction. The presently dominant theory is that interleaving promotes discriminative-contrast, and suggests that category similarity structure modulates this interleaving benefit: that blocking should benefit learning when…

Two experiments tested whether a peak-shifted generalization gradient could be explained by the averaging of distinct gradients displayed in subgroups reporting different generalization rules. Across experiments using a causal judgment task (Experiment 1) and a fear conditioning paradigm (Experiment 2), we found a close concordance between…

A robust finding in humans and animals is that intermixed exposure to 2 similar stimuli (AX/BX) results in better discriminability of those stimuli on test than does exposure to 2 equally similar stimuli in 2 separate blocks (CX_DX)--the intermixed-blocked effect. This intermixed-blocked effect may be an example of the superiority of spaced over…

This experiment evaluated the contributions of frequency and contingency of reinforcement to the deprivation-satiation phenomenon. The findings indicated that the perceived contingency of reinforcement is a more powerful determinant of its subsequent reinforcement effectiveness than is its frequency. (JMB)

Response to PS 502 660. (CB)

A brief report of this research was presented at the 1967 biennial meeting of the Society for Research in Child Development. (MH)