Slowed lexical-semantic activation in individuals with right hemisphere brain damage?

Abstract

This study investigated whether prolonged interference from contextually inappropriate semantic activation after right hemisphere damage (RHD) could be related to a slowing of lexical-semantic activation. A total of 9 adults with RHD and 8 non-brain-damaged adults judged whether auditory probe words fit the overall meaning of sentence stimuli that were biased to one interpretation of a sentence-final lexical ambiguity. Probes, presented at 0 and 1000 ms interstimulus intervals (ISI), represented the contextually inappropriate meanings of the ambiguities. At 0 ms ISI, the control group was predicted to show interference from these contextually inappropriate meanings, but if lexical activation was slowed for RHD participants, no interference would be expected. Although the previous finding of prolonged interference at 1000 ms ISI (Tompkins, Baumgaertner, Lehman, & Fassbinder, 2000) was replicated for the RHD group, neither group showed interference at 0 ms ISI. Potential accounts for these results relate to the possibility of slowed activation in normal ageing, and/ or the effects of strategic processing.