Conditioned Place Preference Extinction

CPP extinction measures the decay of conditioned drug-context associations through repeated non-reinforced exposure to both compartments. After standard CPP has been established, the subject undergoes daily free-access sessions without any drug administration until the preference score returns to baseline. This process engages infralimbic prefrontal cortex (IL-PFC) projections to the nucleus accumbens shell that promote new inhibitory learning rather than erasing the original drug-context association. Understanding extinction mechanisms is central to developing relapse prevention strategies.

The extinction rate is quantified by tracking the CPP score across successive sessions and fitting an exponential decay function to determine the half-life of preference decline. The number of sessions to criterion (CPP score within a predefined threshold of zero) serves as the primary endpoint. Persistent preference despite extended extinction suggests extinction resistance, a phenotype associated with heightened relapse vulnerability. Transition counts and locomotor activity across sessions help distinguish motivational changes from general behavioral suppression.

ConductMaze supports multi-day extinction protocols with automated session scheduling and preference tracking across the full time course. The software computes running CPP scores after each session, plots extinction curves in real time, and applies user-defined criterion thresholds to flag extinction completion. Between-session consistency metrics and within-session time-bin analyses reveal the temporal dynamics of preference decay. All extinction data integrate seamlessly with prior conditioning and subsequent reinstatement phases.