LINGUISTIC CONTEXTUAL INFLUENCES ON CATEGORIZATION SKILLS AFTER TRAUMATIC BRAIN INJURY

This study examined the effect of linguistic context on the graded str ucture representation of common categories in adults with traumatic br ain injury (TBI). Graded structure indicates that all members of a cat egory are not equally representative with some members being better ex amples than others. Ten adults who had suffered traumatic brain injuri es as the result of motor vehicle accidents and 10 age-and gender-matc hed neurologically intact adults participated in the study. The experi mental task consisted of presenting each participant with 20 contextua l sentences and asking them to select the best example of a category l abel mentioned in each sentence. Each of the 20 sentences were followe d by six exemplars: four exemplars of the common category label mentio ned in the sentence and two exemplars that were members of other categ ories. The specific exemplar of the category label was inferred by the context meaning. The neurologically intact adults were significantly more accurate than the TBI adults in choosing the best category exampl e. However, error patterns were similar for each group with both group s choosing a significantly higher proportion of true unrelated exempla rs than any other type of error. Results are discussed relative to the process of restructuring common category graded structure as a result of semantic constraints imposed by linguistic context and limitations in cognitive flexibility observed in TBI adults.