Effects of subdural haematoma on sensorimotor functioning and spatial learning in rats

Twenty per cent of all strokes are haemorrhagic in character and are associ ated with severe disturbances in sensorimotor behaviour and cognition. Alth ough spontaneous recovery of pre-stroke functioning occurs in some cases, t he process is demanding, slow, and often incomplete. A first step in the pr eclinical testing of new putative, neuroprotective and recovery-supporting therapeutics is to validate animal models of brain injury. In a series of f our experiments we evaluated the behavioural impairments and the time cours e of recovery of functional deficits in rats with an experimentally induced subdural haematoma. We found that unilateral subdural haematoma resulted i n dysfunction in both simple reflexive (experiment 1) and skilled sensorimo tor behaviour (experiment 2). Reflexive behaviour did not recover, or recov ered only marginally, and neither did the deficits in skilled forepaw use. Bilateral subdural haematoma impaired the learning and memory performance o f adult (experiment 3) and old rats (experiment 4) in the Morris water esca pe task. Considering the diversity of the deficits found in our experiments , we conclude that different models are needed to cover the broad range of deficits seen in stroke patients. (C) 2000 Elsevier Science Ltd. All rights reserved.