Punishment of alcohol-reinforced responding in alcohol preferring P rats reveals a bimodal population: Implications for models of compulsive drug seeking.
Level 5 - mechanism / opinion, no new human data
Animal research (Oxford CEBM Level 5).
PubMed 28754407 · doi:10.1016/j.pnpbp.2017.07.020
What was done
The authors conducted a retrospective re-examination of training and footshock punishment data collected over several years from a cohort of 499 alcohol-preferring P rats. The data came from experiments using footshock punishment to suppress alcohol seeking in an operant animal model of context-induced relapse, comparing the behavioral response distribution under constant shock intensity for three sessions versus escalating shock intensity.
What was found
Footshock punishment revealed a bimodal distribution in the suppression of alcohol-reinforced responding among alcohol-preferring P rats. This separation into two distinct behavioral subgroups occurred only when rats received constant shock intensity across three sessions, and did not appear when increasing shock intensity was used. The abstract reports no specific numerical values, percentages, or statistical metrics.
Why it matters
This study shows that individual differences in punishment-resistant alcohol seeking emerge under specific conditioning schedules in an otherwise homogeneous animal strain, informing preclinical models of compulsive drug use.
Limits
The findings are restricted to an animal model (alcohol-preferring P rats) and cannot directly establish human clinical validity. The abstract provides no exact shock parameters, quantitative measures of the split, or neurobiological mechanism data.
Cited by
- context In animal experiments where rats are shocked while pressing a bar for alcohol, some rats cease pressing the bar while others paradoxically increase their rate of pressing.