Assessing the elusive cognitive deficits associated with ventromedial prefrontal damage: A case of a modern-day Phineas Gage

Abstract

Cognitive deficits following ventromedial prefrontal damage (VM-PFD) have been elusive, with most studies reporting primarily emotional and behavioral changes. The present case illustrates the utility of a process approach to assessing cognitive deficits following VM-PFD. At age 26, C.D. acquired bilateral VM-PFD, more so in the left frontal region, following a penetrating head injury. Despite exemplary premorbid academic and military performances, his subsequent history suggests dramatic occupational and social changes, reminiscent of Phineas Gage. In fact, lesion analysis revealed similar structural damage to that estimated of Gage. C.D.'s scores on the vast majority of neuropsychological measures were average to superior (e.g., Verbal IQ = 119). However, on several new process measures, particularly those that quantify error rates on multilevel executive function and memory tasks, C.D. exhibited marked impairments. From his pattern of deficits, C.D. appeared to sacrifice accuracy for speed and to adopt liberal response strategies, implicating problems with cognitive inflexibility, impulsivity, and disinhibition. The current findings suggest that VM-PFD may be associated with a wider spectrum of cognitive deficits than previously characterized. (JINS, 2004, 10, 453–465.)