Functional implications of cortical damage

Abstract

Traumatic brain injury has reached epidemic levels, and yet there are still large questions that need to be addressed regarding the underlying pathology and the related behavioral deficits. Adequately measuring the neurological sequelae associated with TBI in vivo requires the use of sophisticated imaging procedures, while quantifying behavioral deficits requires precise, sensitive testing procedures. The current analysis examined three potential biomarkers of TBI using MRI technology, as well as examining both fine motor and psychological function on a cohort of TBI participants at least 12 months post-injury. Ten participants with a history of traumatic brain injury and ten matched controls were recruited for the present analysis. All participants completed a series of four MRI scans, as well as a simple motor task and a cognitive test battery. Between group analysis revealed that the two groups could be differentiated based on two MRI measures (BOLD and FA), and on three behavioral measures (Fitts motor task, self-reported symptoms, and impulse control). A within group correlation analysis of the TBI participants did not reveal any significant relationship between the MRI data and behavioral deficits. A group-wide regression analysis, however, revealed that MRI markers of cortical damage significantly predicted deterioration in the Fitts motor task performance. The results of the current study suggest that the long-term effects of TBI are not confined to executive function, and that one's performance of a fine motor task has diagnostic potential.