Journal of neurotrauma
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Journal of neurotrauma · Jan 1992
Cognitive deficits following traumatic brain injury produced by controlled cortical impact.
Traumatic brain injury produces significant cognitive deficits in humans. This experiment used a controlled cortical impact model of experimental brain injury to examine the effects of brain injury on spatial learning and memory using the Morris water maze task. Rats (n = 8) were injured at a moderate level of cortical impact injury (6 m/sec, 1.5-2.0 mm deformation). ⋯ Results revealed that brain-injured rats exhibited significant deficits (p less than 0.05) in maze performance at both testing intervals. Since the Morris water maze task is particularly sensitive to hippocampal dysfunction, the results of the present experiment support the hypothesis that the hippocampus is preferentially vulnerable to damage following traumatic brain injury. These results demonstrate that controlled cortical impact brain injury produces enduring cognitive deficits analogous to those observed after human brain injury.
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Journal of neurotrauma · Jan 1992
Continuous monitoring of posttraumatic cerebral blood flow using laser-Doppler flowmetry.
Traumatic brain injury causes alterations in cerebral blood flow that are thought to influence secondary pathophysiology and neurologic outcome in humans. Since it is difficult to study early changes in blood flow in head-injured patients, animal models of brain injury must be employed. However, techniques to monitor brain blood flow in animals are labor intensive and generally provide discontinuous flow measurements. ⋯ Blood flow at 60 min was 93% +/- 5% of control in the sham-injured group (n = 10). The reduction in cerebral blood flow in our laser-Doppler study was of similar magnitude as previously reported in rats injured at a similar intensity when blood flow was examined with radiolabeled microspheres. Given these results, we believe laser-Doppler flowmetry can be used to continuously monitor posttraumatic blood flow following experimental brain injury.