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http://dx.doi.org/10.1037/h0029462
Reinforced independent groups of male Sprague-Dawley and Holtzman rats (N = 54) by either hypothalamic stimulation, septal stimulation, or liquid food in a 2-choice brightness-discrimination task. Both groups receiving intracranial reinforcement learned the brightness discrimination more rapidly than the food-reinforced group. The superiority of hypothalamic and septal reinforcement persisted even when, in Exp. II, the ICS was withheld for 1 sec. following each correct response. Such a result rules out the possibility that the small but unavoidable delay associated with the delivery of food is responsible for the differences in learning between the food- and intracranial-reinforcement groups. The incentive or motivational properties of the food and ICS, as indexed by tests of running speed, appeared to be of comparable value. It is suggested that certain temporal characteristics of intracranial reinforcement may provide more favorable conditions for learning than food reinforcement. (28 ref.) (PsycINFO Database Record (c) 2016 APA, all rights reserved)