Cognitive representations of semantic categories

Conducted 9 experiments with a total of 663 undergraduates using the technique of priming to study the nature of the cognitive representation generated by superordinate semantic category names. In Exp I, norms for the internal structure of 10 categories were collected. In Exps II, III, and IV, internal structure was found to affect the perceptual encoding of physically identical pairs of stimuli, facilitating responses to physically identical good members and hindering responses to identical poor members of a category. Exps V and VI showed that the category name did not generate a physical code (e.g., lines or angles), but rather affected perception of the stimuli at the level of meaning. Exps VII and VIII showed that while the representation of the category name which affected perception contained a depth meaning common to words and pictures which enabled Ss to prepare for either stimulus form within 700 msec, selective reduction of the interval between prime and stimulus below 700 msec revealed differentiation of the coding of meaning in preparation for actual perception. Exp IX suggested that good examples of semantic categories are not physiologically determined, as the effects of the internal structure of semantic categories on priming (unlike the effects for color categories) could be eliminated by long practice.