Neuroanatomic and neuropsychological predictors of unawareness of cognitive deficit in the vascular population

Abstract

Unawareness of cognitive deficit following brain damage was investigated in a sample of 108 cerebrovascular accident patients and 30 orthopaedic controls. The purpose of this study was to: 1. investigate the incidence of unawareness, 2. test if neurocognitive factors were predictive of unawareness, and 3. determine which specific neuroanatomic lesion sites were predictive of the phenomenon. Neuroanatomic lesion site was identified by CT/MRI. Unawareness of cognitive deficit was assessed using a structured unawareness interview, while neurocognitive status was quantified on several indices. Results showed unawareness was associated with brain injury (p <.0001), occurred in varying degrees of severity in about 40% of the cerebrovascular group, was significantly correlated with various neurocognitive indices, and was more frequently associated with cortical verses subcortical lesion sites (p <.0001). The results could partially be explained by existing theoretical models, but showed that both degree of neurocognitive impairment and neuroanatomic lesion site are predictive variables of the unawareness phenomenon. The potential clinical use of unawareness screening as a part of routine neuropsychological evaluation was discussed.