Verbal Discrimination: Re-Pairing, Language Frequency, and Associative Properties of the Stimuli

Abstract

Four experiments provide evidence that (a) language frequency of the stimuli can influence the rate of learning of a verbal discrimination, (b) re-pairing of the 'correct' and 'incorrect' members of pairs has little effect if introduced from the outset but produces performance decrements if introduced when the list is nearly learned, (c) these re-pairing decrements occur differentially for lists that differ in preexperimental interitem associations, and (d) the intrapair associations formed during the learning of a verbal-discrimination task are not incidental to performance on that task. The present paper reports the results of four experiments on verbaldiscrimination learning. These experiments manipulated the associative properties and the language frequency of stimuli, as well as the pairings of 'right' and 'wrong' items within a list. In a typical verbal-discrimination task, the subject is successively presented pairs of verbal items and must learn which member of each pair has been arbitrarily designated as correct by the experimenter; the pairing of items is constant, but the positions of an item within the pair and of a pair within the list vary from trial to trial. According to the frequency theory of verbal-discrimination learning (Ekstrand, Wallace, and Underwood, 1966), the subject performs this task by discriminating between the subjective frequencies accrued to the 'correct' and 'incorrect' members of each pair in the experimental setting. An item gains frequency increments as a consequence of being seen, given as an overt response, or covertly rehearsed. Correct items build up frequency faster than incorrect items, and the subject comes to be able to respond without error by applying this strategy to all pairs: 'Choose the member with the greater subjective frequency.' If the frequency theory is correct and the subject indeed discriminates between the subjective frequencies elicited by the two members of the pair, rather than between, say, any semantic properties of the words