A Characterization of Approach and Avoidance Learning in Alcohol‐Preferring and Alcohol‐Nonpreferring Rats

Abstract

Although numerous biochemical and physiological differences have been shown to be correlated with alcohol preference, less is known about behavioral factors that may correlate with alcohol preference. Using a signaled barpressing task, alcohol-preferring (P; n = 18) and alcohol-nonpreferring (NP; n = 19) rats were compared for their ability to learn an appetitive and an aversive task. Results showed that P rats had difficulty learning the tasks in comparison with NP and nonselected, control rats when appetitive training was given first. However, if aversive training came first, the NP rats performed poorly in comparison with the P and nonselected rats. These results suggest that these lines of rats may differ in behavioral inhibition and sensitivity to conditioned fear. Furthermore, these behavioral differences may offer a richer analysis of the traits that were co-selected with the alcohol-seeking and alcohol-avoiding phenotypes.

Alcohol-Preferring P Rats Exhibit Elevated Motor Impulsivity Concomitant with Operant Responding and Self-Administration of Alcohol

“…While the HAD2s’ behavior was also associated with high levels of free access alcohol drinking, they were characterized by passive avoidance and an increased latency to explore a novel environment. Salimov () ultimately characterized the P rats as having “alcohol drive with novelty seeking and persistence,” while the HAD rats have “alcohol drive with timidity and meekness.” Similarly, HAD2s, but not P rats, have been seen to possess an avoidance (but not appetitive) learning deficit that may be due to increased anxiety (Blankenship et al., , ). This view is supported by findings that the HAD2s avoidance learning deficit is decreased with moderate levels of alcohol, presumably via its anxiolytic effects (Rorick et al., ), and the HAD2s have increased heart rate reactivity in a Pavlovian fear conditioning paradigm (Rorick et al., ).…”

A Characterization of Approach and Avoidance Learning in High–Alcohol‐Drinking (HAD) and Low–Alcohol‐Drinking (LAD) Rats

“…Analyses of response onset and total number of bar-presses performance revealed no significant differences between the three groups. As in previous studies with other strains of rats (Blankenship et al, 1998;Steinmetz et al, 1993), during avoidance training, the LAD1 and N/Nih rats provided well-timed avoidance responses just prior to shock onset. In the appetitive condition, all rats responded soon after tone onset.…”

“…Interestingly, the performance of HAD1 and HAD2 rats on the avoidance task differ greatly from the performance of P rats. We previously reported that there were differences in the behavioral performance of P and NP rats on these tasks, relative to Wistar rats, but that the difference was strongly dependent on the order of training given (Blankenship et al, 1998). When appetitive training was given first, the P rats showed retarded rates of learning the appetitive tasks relative to the NP and Wistar rats as well as a retarded rate of learning the avoidance task when the aversive training was given second.…”

“…The training procedures reported here were identical to those used in a previous study involving P and NP rats (Blankenship et al, 1998). The HAD1 and LAD1 rats received both aversive and appetitive signaled bar-press training with the order of training counterbalanced across rats.…”

“…We recently reported the results of a study in which P, NP, and Wistar rats were compared on appetitive and aversive signaled bar-pressing tasks (Blankenship et al, 1998;Steinmetz et al, 1993). When aversive training was given first, relative to the NP and Wistar rats, the P rats performed poorly on the aversive tasks and also performed poorly on the appetitive task that followed.…”