[Effect of psychotropic substances on orienting-exploratory behavior after startling caused by acoustic stimulation]

Frightening sound stimulation induced alarm and alertness which resulted in weakening of attention to novel environment and increasing of orienting response to the source of the frightening sound. Defense motivation occurring under these conditions failed to alter with the increase of sound loudness. Tranquilizers (diazepam, chlordiazepoxide, benatyzine), antidepressants (amytriptiline, imipramine) and some neuroleptics (trifluoperazine, haloperidol) in a low doze prevented these disturbances. High doses of pentobarbital, chlorpromazine, as well as trifluoperazine and haloperidol did not prevent the mentioned consequences of emotional excitation.