Cross-modal priming and explicit memory in patients with verbal productiondeficits

Implicit memory is often thought to reflect an influence of past experience on perceptual processes, yet priming effects are found when the perceptual format of stimuli changes between study and test episodes. Such cross-moda l priming effects have been hypothesized to depend upon stimulus recoding p rocesses whereby a stimulus presented in one modality is converted to other perceptual formats. The present research examined recoding accounts of cro ss-modal priming by testing patients with verbal production deficits that p resumably impair the conversion of visual words into auditory/phonological forms. The patients showed normal priming in a visual stem completion task following visual study (Experiment 1), but showed impairments following aud itory study in both implicit (Experiment 2) and explicit (Experiment 3) ste m completion. The results are consistent with the hypothesis that verbal pr oduction processes contribute to the recoding of visual stimuli and support cross-modal priming. The results also indicate that shared processes contr ibute to both explicit memory and cross-modal implicit memory, (C) 1999 Aca demic Press.