Frontal lobe lesions, diffuse damage, and neuropsychological functioning in traumatic brain-injured patients

This study quantified lesion volume in relation to damage location and executive functioning in traumatic brain-injured (TBI) patients. Magnetic resonance (MR) scans of 68 TBI patients were analyzed by taking volumetric measures of lesion sites. Patients were grouped according to the presence/absence of frontal lobe lesions. Measures of frontal lesion volume were studied as predictors for outcome on designated tests of executive functioning (Halstead Category Test and Wisconsin Card Sorting Test). Results showed no significant differences in level of deficit between groups. In addition, no significant differences were found between groups on other tests of neuropsychological functioning (Trail Making Test, Parts A and B, and Wechsler Adult Intelligence Scale-Revised). These results suggest that tests that are traditionally used to detect "frontal lobe" damage may not be adequate for distinguishing specific frontal lobe dysfunction, and do not add anything unique about frontal lobe integrity and neuropsychological functioning in TBI patients.