We examined the relationship of preinjury intelligence, brain tissue volume loss, lesion location, demographic variables and a number of genetic markers to long-term cognitive decline in a group of Vietnam veterans with predominantly penetrating head injury (PHI) suffered more than thirty years ago. Using linear and stepwise regression procedures, we found that those with PHI demonstrated a greater degree of cognitive decline overall during the years following injury compared to a control group of uninjured Vietnam veterans. This became increasingly significant later in life. We also found that preinjury intelligence was the most consistent predictor of cognitive outcome across all phases of potential recovery and decline after such injuries. Laterality of lesion was not a factor. Finally, we found evidence for an association between level of cognitive decline following penetrating head injury and the possession of certain genetic markers that have been linked with brain injury and neurodegeneration. Thus exacerbated decline does occur in Vietnam veterans with PHI, is apparently unrelated to dementia and is determined by multiple factors (most notably preinjury intelligence).

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Intramural Research (Z01)
Project #
1Z01NS003024-01
Application #
7594715
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
1
Fiscal Year
2007
Total Cost
$342,622
Indirect Cost
City
State
Country
United States
Zip Code
Barbey, Aron K; Colom, Roberto; Grafman, Jordan (2013) Dorsolateral prefrontal contributions to human intelligence. Neuropsychologia 51:1361-9
Koenigs, Michael; Huey, Edward D; Raymont, Vanessa et al. (2008) Focal brain damage protects against post-traumatic stress disorder in combat veterans. Nat Neurosci 11:232-7
Frattali, Carol; Hanna, Rebecca; McGinty, Anita Shukla et al. (2007) Effect of prefrontal cortex damage on resolving lexical ambiguity in text. Brain Lang 102:99-113
Goel, Vinod; Tierney, Michael; Sheesley, Laura et al. (2007) Hemispheric specialization in human prefrontal cortex for resolving certain and uncertain inferences. Cereb Cortex 17:2245-50
Raymont, Vanessa; Grafman, Jordan (2006) Cognitive neural plasticity during learning and recovery from brain damage. Prog Brain Res 157:199-206