Cj. Slawecki et al., Presentation of an ethanol-paired stimulus complex alters response patterns during extinction, PHARM BIO B, 62(1), 1999, pp. 127-135
It has been hypothesized that environmental stimuli previously paired with
ethanol consumption play a role in excessive ethanol intake. This study exa
mined the ability of orally self-administered ethanol to establish a tone-l
ight stimulus complex as a conditioned reinforcer (CSR). Male Long-Evans ra
ts were trained to orally self-administer 10% ethanol (10E) using the sucro
se-substitution procedure. During training, a tone-light stimulus complex w
as paired with ethanol presentation in a stimulus complex paired (SC paired
) group but not in a control group. Responding during extinction in the pre
sence and absence of the stimulus complex was then examined. Following the
initiation of ethanol self-administration, 10E maintained greater respondin
g in the SC paired group compared to the control group. When the stimulus c
omplex was presented contingent on responding during extinction, the rate o
f extinction was slightly attenuated in the SC-paired group but not in the
control group. The altered rate of extinction in the SC-paired group was ch
aracterized by: 1) a slight decrease in total session responding over succe
ssive days of extinction and 2) a transient attenuation of extinction burst
response rate during the first extinction session. These data suggest the
stimulus complex could function as a weak CSR, but overall its ability to m
aintain lever pressing was minimal. (C) 1998 Elsevier Science Inc.