Exploratory drive and secondary reinforcement in the acquisition and extinction of a simple running response.

Reciprocal Inhibitory Interactions Between the Reward-Related Effects of Leptin and Cocaine

“…Leptin did attenuate the establishment of cocaine-conditioned place preferences, a well-established consequence of drug reward (Tzschentke, 2007), as well as cocaine-seeking under unexpected extinction conditions, a behavior that is significantly prolonged by conditioned reinforcers (Mote and Finger, 1942). Conditioned reinforcers-reward-predictive cues such as the cocaine-associated cue light in the present study-drive the dopamine system almost immediately (Schultz, 1998;Phillips et al, 2003;Stuber et al, 2005) and have a critical role in behaviors that involve a significant delay in primary reinforcement (Spence, 1947), as is the case with i.v.…”

Response latency as a function of the amount of reinforcement.

“…But latency, on the contrary, has proven to be a fruitful measure, for a number of reasons which may profitably be reviewed here. Latency has been used in conventional types of experimental situations such as the lever-pressing, jumping-stand, and runway (3,4,9,7,8,17,18,19,21), to demonstrate successfully a wide range of behavioral phenomena. As has been pointed out by Graham and Gagn£ (9), latency quantifies in units of a known physical dimension, and thus facilitates comparison with the data of related disciplines.…”

A positive relationship between reinforcement and resistance to extinction produced by removing a source of confusion from a technique that had produced opposite results.

“…In view of the theoretical importance of the problem, it seems desirable to see if Finger's results mean that there is no lawful relationship between the number of reinforcements and resistance to extinction or if, on the other hand, they were a function of some aspect of his experimental technique that introduced a disturbing factor counteracting the effects of reinforcement. The fact that Finger's technique has been used in a number of coordinated studies (2,3,5,6,7,8,13,14,15) designed to investigate the variables influencing learning, increases the desirability of determining whether or not it involved such a source of confusion. That the technique may have contained some peculiar factor of this kind is suggested by a second paradoxical result found in the above studies: namely, that animals 494…”