Extinction-induced spatial dispersion in the radial arm maze: Arrest by ethanol.

Abstract

Adaptive changes in response to extinction can be observed if provisions are made that permit behavior to shift away from trained routine. In the present case, the baiting of four arms in the eight-arm radial maze increasingly restricted subject movements to those arms. The unbaited arms afforded a new direction for behavior to take during extinction. Withdrawal of reward was followed by an immediate and active expansion of sites visited. The previously unrewarded arms were now regularly sampled. This was one consequence of extinction. The other was the well-known decline in overall rate of arm entry, whether arms were previously baited or not. Ethanol, at doses of 1.5 or 2.0 g/kg, eliminated the spatial dispersion attendant upon nonreward. It did not affect the decline in overall responsiveness. Ethanol's deletion of extinction-induced spatial variability may account for its impairment on reversal and other kinds of tasks that require a shift away from old patterns of behavior.

EFFECTS OF D-AMPHETAMINE AND ETHANOL ON VARIABLE AND REPETITIVE KEY-PECK SEQUENCES IN PIGEONS

“…The results of the present experiment are relevant to several other areas of investigation. The ethanol-induced response-sequence repetition in both components (Figure 4) is consistent with other reports of alcohol increasing behavioral repetition in both operant (e.g., Crow, 1982Crow, , 1988 and radial-arm maze (e.g., Devenport, 1984;Devenport & Merriman, 1983) experimental preparations. When variability is indexed as changes in U value (Figure 3), however, our results also are consistent with reports of alcohol increasing behavioral variability (Cohen et al, 1990;McElroy & Neuringer, 1990).…”

Effects of Ethanol on Reinforced Variations and Repetitions by Rats Under a Multiple Schedule

“…When performances of rats were compared with the simulated random generator, alcohol was seen to change the rats' behavior in the direction of the random generator. Under control conditions, rats avoid repetitions of arm entries more than would be expected by chance (e.g., Devenport, 1983Devenport, , 1984. Alcohol increases repetitions, resulting in a closer approximation to a ran- UJ 10-F 0 m -ALCOHOL AND BEHAVIORAL VARIABILITY dom generator.…”

“…Rats make relatively few "errors," defined by repeated visits to a given arm, and, furthermore, visit arms in quasi-random fashion (i.e., they do not follow a fixed pattern of visitations). Alcohol, especially at higher doses, increases repetitions and therefore increases errors (Devenport, 1984;). The conclusion reached from these results has been that alcohol is "an agent of behavioral stereotypy" (Devenport et al, 1983, p. 58), a conclusion that appears to conflict with the present results.…”

Indices of extinction-induced “depression” after operant learning using a runway vs. a cued free-reward delivery schedule

“…Operant extinction results in elevated levels of corticosterone in rodents (Coover, Goldman, & Levine, 1971;Kawasaki & Iwasaki, 1997), indicating that the loss of reinforcement represents stress for the animal. Furthermore, during operant extinction rats exhibit a greater spatial variability (Devenport, 1984) and respond to it with an increase in aggressiveness (Azrin, Hutchinson, & Hake, 1966;Dantzer, Arnone, & Mormede, 1980), motor activation (Flaherty, 1982;Flaherty, Troncoso, & Deschu, 1979), anxiety-like behavior Schulz et al, 2007a) or escape responses (Bentosela, Barrera, Jakovcevic, Elgier, & Mustaca, 2008;Daly, 1974;Huston et al, 2012;Komorowski et al, 2012;Norris, Pérez-Acosta, Ortega, & Papini, 2009). We hypothesized, that withdrawal from positive reward during extinction could serve as a behavioral marker of a depressive-like state and examined this question by using a cued fixed-time reward delivery paradigm in an elongated operant chamber as well as food-reinforced lever-pressing response in a Skinner-box, which was connected to a withdrawal chamber Komorowski et al, 2012).…”