Date of Award

January 2020

Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Joseph Miller


The Auditory Consonant Trigrams (ACT) has historically been used in research and clinical settings as a measure of working memory ability, though previous research has failed to identify the precise cognitive processes and abilities measured by the task. The ACT total score (ACT T) has been shown to be sensitive to numerous clinical neurological and psychological populations (i.e., TBI, ADHD, MS, MDD). Alternatively, little is known about the ACT perseveration score (ACT P), the current study aimed to identity the ACT T and ACT P’s relationships to other neuropsychological measures and their clinical utility within diverse clinical/neurological presentations. In a sample of patients referred for neuropsychological evaluation (N = 448), an exploratory factor analysis revealed a 2-factor model accounting for 49.54% of the variance within the sample. The ACT T and ACT P loaded on a factor with measures of higher-order executive functioning accounting for 9.99% of the variance within the sample. Further, the clinical utility of the ACT T and ACT P was found to be limited within the current sample with a trend of the ACT T discriminating the severity of brain damage within TBI, while the ACT P tended to discriminate diagnostic groups. These findings suggest that the ACT scoring methods may be too simplistic to identify subtle cognitive changes in clinical populations.