Article

Cognitive sequelae of head injury: Involvement of basal forebrain and associated structures

Wolfson Brain Imaging Centre, University of Cambridge, Addenbrooke's Hospital, Box 65, Cambridge CB2 2QQ, UK.
Brain (Impact Factor: 9.2). 02/2005; 128(Pt 1):189-200. DOI: 10.1093/brain/awh352
Source: PubMed

ABSTRACT

Traumatic brain injury is the most common cause of death and disability in young people and survivors often suffer from chronic cognitive deficits. From animal, post-mortem and cognitive studies, there is now increased evidence that abnormalities in the cholinergic system may be underlying some of these deficits. This study investigated this hypothesis in a group of survivors of moderate-severe head injury (n = 31). Patients completed a comprehensive neuropsychological assessment and an MRI scan. Compared with a group of controls (matched on age, sex and premorbid intelligence quotient), the patients showed deficits in sustained attention, paired associate learning and reaction time, but comparative preservation of spatial working memory. Voxel-based morphometry revealed reduced grey matter density in the head injured group in the basal forebrain, the hippocampal formation and regions of the neocortex. These cognitive and structural results are consistent with cholinergic dysfunction. These preliminary findings suggest that cholinergic enhancers may be an effective treatment of cognitive deficits post head injury.

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    • "Yet, the association between infratentorial volume and postural impairments has not directly been evaluated. Some studies in TBI patients have demonstrated reduced regional volumes in the cerebellum and brain stem as part of whole brain voxel-based analyses [Bendlin et al., 2008; Gale et al., 2005; Kim et al., 2008; Salmond et al., 2005; Sidaros et al., 2009]. However, standard whole-brain normalization procedures generally lead to relatively poor alignments in infratentorial structures [Diedrichsen, 2006] and, thus, do not allow for a precise localization of the volumetric differences. "
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    • "Other neuropathological findings in surgical specimens from patients with TLE described granule cell dispersion and temporal lobe sclerosis (47). Other, less frequently affected regions of the brain include selective neurons of the thalamus, basal forebrain, cerebellum, and brain stem (57, 58). "
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