LEARNING IMPAIRMENTS CAUSED BY LESIONS TO THE PEDUNCULOPONTINE TEGMENTAL NUCLEUS - AN ARTIFACT OF ANXIETY

Bilateral N-methyl-D-aspartate lesions of the pedunculopontine tegment al nucleus (PPTg) blocked the acquisition of a delayed non-matching to position task (DNMP) performed in a T-maze. This acquisition impairme nt, however, was reversed by pre-testing injections of diazepam (1 mg/ kg). These results, in addition to the finding that PPTg lesions eleva ted anxiety as measured by the elevated plus maze, suggest that PPTg i s not involved in learning or memory, but in the regulation of anxiety . (C) 1998 Elsevier Science B.V. All rights reserved.