Lesions of the pedunculopontine tegmental nucleus do not alter delayed non-matching to position accuracy.

The cholinergic pedunculopontine tegmental nucleus, located in the brainstem, and part of the reticular formation, has traditionally been linked to motor function, sleep and arousal, but has recently been implicated in cognition. To investigate this possibility, rats with radiofrequency lesions were tested on a delayed non-matching to position task, a test for spatial recognition memory abilities. Data were analysed according to the methods of signal detection theory. Lesions of the pedunculopontine nucleus did not produce marked deficits in accuracy, although there was some evidence to suggest that motivational processes could have been affected.