In a recent review paper by professor Arjan Blokland, the effects of scopolamine and biperiden (and pirenzepine) are compared in animal studies and related to findings in humans.
Scopolamine is used as a golden standard to induce memory impairments in animals and man. It has been used to validate new drugs for dementia-related disorders. However, the predictive validity of the scopolamine model is poor. Moreover, scopolamine is a non-selective muscarinic antagonist and associated with various side effects. Biperiden is a more selective muscarinic antagonist and appears to selectively impair episodic memory. Biperiden could be considered as an interesting model for memory impairments in the early stages of dementia.
It is concluded that the effects on cognitive functions are different for scopolamine and biperiden, and they should be considered as different cognitive deficit models.
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