Suppression and narrative time shifts in right hemisphere brain damage

Narrative comprehension is vital to socializing and everyday communication. Understanding references to time is fundamental to comprehending the context and order of events within a narrative. This study examined the functioning of a central comprehension mechanism, suppression1,2, in narratives that cue a shift in timeframe in individuals with right hemisphere brain damage (RHD). The timeframe in normal narrative processing is assumed to be continuous3-4. Shifts in the timeframe of events trigger the suppression mechanism, which reduces a comprehender’s mental activation of information that was processed before the time shift. When the timeframe of a narrative is disrupted (e.g., something happens “an hour later”), information that was mentally active before the time shift becomes less relevant and is suppressed. Suppression is a general comprehension mechanism that acts across language levels and domains (e,g, words, sentences, narratives, etc.)1,5. Based on evidence of RHD suppression deficit in lexical ambiguity processing6-7, it was predicted that adults with RHD would also have difficulty suppressing information from a prior timeframe following a shift in narrative timeline. In addition, we predicted a correlation between suppression and narrative comprehension, as reported previously for young normal comprehenders1-2,5 and adults with RHD6