Nimodipine alters acquisition of a visual discrimination task in chicks.
Chicks 5 days old received intraperitoneal injections of nimodipine 30 min before training on either a visual discrimination task (0, 0.5, 1.0, or 5.0 mg/kg) or a test of separation-induced distress vocalizations (0, 0.5, or 2.5 mg/kg). Chicks receiving 1.0 mg/kg nimodipine made significantly fewer visual discrimination errors than vehicle controls by trials 41-60, but did not differ from controls 24 h later. Chicks in the 5 mg/kg group made significantly more errors when compared to controls both during acquisition of the task and during retention. Nimodipine did not alter separation-induced distress vocalizations at any of the doses tested, suggesting that nimodipine's effects on learning cannot be attributed to a reduction in separation distress. These data indicate that nimodipine's facilitation of learning in young subjects is dose dependent, but nimodipine failed to enhance retention.
Deyo
R
R
Department of Psychology, Northwestern University, Evanston, Illinois 60208.
Panksepp
J
J
Conner
R L
RL
D000367:Age Factors; D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects; D001143:Arousal / Q000187:drug effects*; D002645:Chickens; D003118:Color Perception / Q000187:drug effects; D004193:Discrimination Learning / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005556:Form Perception / Q000187:drug effects*; D008568:Memory / Q000187:drug effects*; D011939:Mental Recall / Q000187:drug effects*; D009553:Nimodipine / Q000494:pharmacology*; D010364:Pattern Recognition, Visual / Q000187:drug effects*; D012858:Size Perception / Q000187:drug effects
D009553:Nimodipine