No abstract

No abstract

Retention of detour learning in turtles over 10-day and 60-day intervals was demonstrated. The detour problem required Ss to escape from a walled enclosure by turning away from a much preferred expanse of daylight visible through a barred panel. Disruption of the learned pattern by antecedent confinement was also demonstrated when Ss reverted to more direct but inadequate modes of escape. This performance decrement was minimized when Ss were confined under chlorpromazine and amobarbital, and enhanced following amphetamine sulphate administration. It was suggested that interfering responses were established under an emotional state induced by walled confinement and persisted in the postconfmement period.

No abstract

Speed with which 9 turtles (Chrysemys picta marginata) traversed a 36 in. runway following 2-hr, and 6-hr, periods of dry confinement in small cells was more than double the speed immediately following withdrawal from S's home tank. Using antecedent confinement and contingent natation or disorientation for correct and incorrect choices, respectively, this species demonstrated intermediate brightness discrimination. 4 of 5 Ss learned a black-gray discrimination in 8-66 trials. In a discrimination involving the same gray and a white cue, S's failure to give clear evidence of responding either to relational or absolute stimulus properties is probably the consequence of sensory deficiencies, a finding supported by failure of 4 other Ss to learn a gray-white discrimination.