Spoken-word processing in aphasia: Effects of item overlap and item repetition

Abstract

Two studies were carried out to investigate the effects of presentation of primes showing partial (word-initial) or full overlap on processing of spoken target words. The first study investigated whether time compression would interfere with lexical processing so as to elicit aphasic-like performance in non-brain-damaged subjects. The second study was designed to compare effects of item overlap and item repetition in aphasic patients of different diagnostic types. Time compression did not interfere with lexical deactivation for the non-brain-damaged subjects. Furthermore, all aphasic patients showed immediate inhibition of co-activated candidates. These combined results show that deactivation is a fast process. Repetition effects, however, seem to arise only at the longer term in aphasic patients. Importantly, poor performance on diagnostic verbal STM tasks was shown to be related to lexical decision performance in both overlap and repetition conditions, which suggests a common underlying deficit.

Varieties of semantic ‘access’ deficit in Wernicke’s aphasia and semantic aphasia

“…Similarly, patients with Wernicke’s aphasia show repetition priming effects, absent in some other types of aphasia ( Blumstein et al , 2000 ). These effects have been linked to deficits in activating lexical representations and in auditory working memory ( Janse, 2008 ). For the first time, however, our findings indicate that this repetition priming effect goes beyond the verbal domain: patients with Wernicke’s aphasia found it difficult to activate the meaning of an item from a single presentation irrespective of modality.…”

The role of Broca's area in regular past-tense morphology: An event-related potential study

“…For instance, Broca’s aphasics showed a reduction in priming between semantically related words when the initial phoneme of the prime word was phonetically altered (e.g., c*at-dog ) or replaced by another (e.g., gat-dog ) (Milberg et al, 1988; Aydelott Utman et al, 2001; Misiurski et al, 2005; for a review see Blumstein, 2007; also see Janse, 2006, 2008). Thus, regarding the present two-word priming design, this view might also predict a reduction in word-onset ortho-phonological priming, which would account for reductions in behavioral priming effects for the regular-verb, pseudopast, and orthophono conditions, with relative preservation of irregular-verb priming.…”

How robust are exemplar effects in word comprehension?

“…Exemplar effects have been established in several priming experiments (e.g., Bradlow, Nygaard, and Pisoni, 1999;Craik and Kirsner, 1974;Goh, 2005;Goldinger, 1996;Janse, 2008;Mattys and Liss, 2008;McLennan et al, 2003;McLennan and Luce, 2005;Palmeri, Goldinger, and Pisoni, 1993).…”

“…Many articles in the literature point to a role of exemplars in word comprehension. This study investigates the robustness of these exemplar effects.Exemplar effects have been established in several priming experiments (e.g., Bradlow, Nygaard, and Pisoni, 1999;Craik and Kirsner, 1974;Goh, 2005;Goldinger, 1996;Janse, 2008;Mattys and Liss, 2008;McLennan et al, 2003;McLennan and Luce, 2005;Palmeri, Goldinger, and Pisoni, 1993).These experiments contained repeated words and the comprehension of the second occurrence of a word (the target) is expected to be facilitated by the first occurrence (the prime). Primes and targets were completely identical, that is the same token, or they differed in speech rate, time-compression, the realization of a certain segment (e.g., intervocalic /t,d/ produced as [t,d] or as a flap in American English), or the speaker's voice.…”