Interaction among d-amphetamine, scopolamine and genotype in avoidance behavior of rats.

Effects of d-amphetamine and scopolamine were investigated on either-way avoidance in two genetic lines. In the either-way task, the animal has the option to respond in either of the two directions available. Differences between the genetic lines were statistically significant under the effects of scopolamine, but were absent under the effects of d-amphetamine. It seems that scopolamine is more likely to disrupt responsiveness to visual stimuli in the low-avoidance line and this difference in responsiveness is influenced by bidirectional genetic selection.