Background and Purpose-Cognitive decline occurs in Ϸ30% of stroke patients. Acute risk factors have been identified, but long-term risk has not been examined in large samples. The purpose of this research was to determine factors associated with the progression of cognitive impairment after stroke. Methods-Consecutive stroke patients (193)

Using a fixed behavioral test-resistance to extinction of avoidance responding in rats in the Baum box-the effects of delta 8-THC were examined with the drug at various degrees of decomposition. Partially decomposed THC had no significant overall effect on avoidance-extinction responding. However, substantially decomposed THC produced significant extreme reactions in one group of rats, with some subjects showing virtually no extinction responding, whereas others displayed greatly increased responding. In Experiment 2, pure delta 8-THC was found to significantly hasten extinction, but only if rats had never experienced the drug before (i.e., a tolerance effect was demonstrated). Drug dosage throughout was 5 mg/kg.