Executive Attention Deficits In Persons With Aphasia: Conflict Resolution and Goal Maintenance

An understanding of the relationship between attentional deficits and language processing can provide insight into the language disorders in persons with aphasia (PWA) (McNeil, Odell & Tseng, 1991). Executive attention is a critical component of the attentional system (Cowan, 2005). Core features of executive attention are goal maintenance and conflict resolution (Engle, Kane & Tuholski, 1999). The relationships among executive attention, language processing and aphasia have not been studied extensively.\ud The purpose of this study was to investigate the role of goal maintenance and conflict resolution in word-level processing in PWA. Picture-Word Interference (PWI) tasks were used whereby written words were superimposed on pictures in congruent (word and picture match), neutral (word with polygon) or incongruent (word with non-matching picture) conditions. The incongruent condition was presented at 19% and 73% proportion. Ten PWA and 20 normal individuals (NI) categorized words into animal or non-animal. Button press response times (RT) and error were measured. Conflict resolution was measured by comparing RTs in the incongruent condition to those in both the neutral and congruent conditions. Goal maintenance was measured by comparing Errors on the incongruent condition between the two proportions. \ud A mixed model examined RTs among conditions for the 19% incongruent proportion between groups. PWA showed significantly (p<.05) longer RTs for the incongruent and neutral conditions, but no significant group difference for the congruent conditions. The NI showed significantly more errors on the lower proportion, however, the PWA showed no significant difference between two proportions. \ud Given that there was no significant group difference on the congruent condition, the significantly longer RTs for the PWA on the incongruent conditions is interpreted as evidence that PWA demonstrated impaired on conflict resolution.\ud The finding that NI showed a significant proportion effect and the PWA did not is interpreted as evidence that the PWA demonstrated impaired goal maintenance. RT and error data indicate deficits of these components of executive attention in the PWA. Moderately high correlation coefficients for the PWA between RTs from the incongruent condition and measures of working memory and aphasia severity suggest a meaningful relationship between these attentional impairments and language processing impairments