Functional reorganisation of memory after traumatic brain injury: a study with H(2)(15)0 positron emission tomography.

Published

Journal Article

OBJECTIVE:To study the effects of moderate to severe traumatic brain injury (TBI) on the functional neuroanatomy supporting memory retrieval. METHODS:Subjects were six patients who had sustained a moderate to severe TBI about four years before scanning and had since made a good recovery. Eleven healthy young adults matched to the patients for age and education served as controls. An established H(2)(15)0 positron emission tomography paradigm was used to elicit brain activations in response to memory retrieval. TBI patients' patterns of brain activation were compared statistically with those of control subjects. Both group and individual case data were analysed. RESULTS:Both TBI patients and controls engaged frontal, temporal, and parietal regions known to be involved in memory retrieval, yet the TBI patients showed relative increases in frontal, anterior cingulate, and occipital activity. The hemispheric asymmetry characteristic of controls was attenuated in patients with TBI. Reduced activation was noted in the right dorsomedial thalamus. Although local aspects of this pattern were affected by the presence of focal lesions and performance differences, the overall pattern was reliable across patients and comparable to functional neuroimaging results reported for normal aging, Alzheimer's disease, and other patients with TBI. CONCLUSIONS:The TBI patients performed memory tasks using altered functional neuroanatomical networks. These changes are probably the result of diffuse axonal injury and may reflect either cortical disinhibition attributable to disconnection or compensation for inefficient mnemonic processes.

Full Text

Duke Authors

Cited Authors

  • Levine, B; Cabeza, R; McIntosh, AR; Black, SE; Grady, CL; Stuss, DT

Published Date

  • August 2002

Published In

Volume / Issue

  • 73 / 2

Start / End Page

  • 173 - 181

PubMed ID

  • 12122177

Pubmed Central ID

  • 12122177

Electronic International Standard Serial Number (EISSN)

  • 1468-330X

International Standard Serial Number (ISSN)

  • 0022-3050

Digital Object Identifier (DOI)

  • 10.1136/jnnp.73.2.173

Language

  • eng