Free versus forced exposure with two procedures for conditioning and measuring fear in the rat.
D000818:Animals; D001522:Behavior, Animal; D003213:Conditioning, Psychological; D004597:Electroshock; D004777:Environment; D004781:Environmental Exposure; D004924:Escape Reaction; D005108:Extinction, Psychological; D005239:Fear; D008297:Male; D011678:Punishment; D051381:Rats; D013997:Time Factors