Characterizing Different Strategies for Resolving Approach-Avoidance Conflict

Abstract

The ability of animals to maximize benefits and minimize costs during approach-avoidance conflicts is an important evolutionary tool, but little is known about the emergence of specific strategies for conflict resolution. Accordingly, we developed a simple approach-avoidance conflict task in rats that pits the motivation to press a lever for sucrose against the motivation to step onto a distant platform to avoid a footshock delivered at the end of a 30 s tone (sucrose is available only during the tone). Rats received conflict training for 16 days to give them a chance to optimize their strategy by learning to properly time the expression of both behaviors across the tone. Rats unexpectedly separated into three distinct subgroups: those pressing early in the tone and avoiding later (Timers, 49%); those avoiding throughout the tone (Avoidance-preferring, 32%); and those pressing throughout the tone (Approach-preferring, 19%). The immediate early gene cFos revealed that Timers showed increased activity in the ventral striatum and midline thalamus relative to the other two subgroups, Avoidance-preferring rats showed increased activity in the amygdala, and Approach-preferring rats showed decreased activity in the prefrontal cortex. This pattern is consistent with low fear and high behavioral flexibility in Timers, suggesting the potential of this task to reveal the neural mechanisms of conflict resolution.

Neural correlates and determinants of approach–avoidance conflict in the prelimbic prefrontal cortex

“…Individual differences in risky decision making have also been reported in other studies using rodent models of behavioral conflict involving footshock punishment (Simon et al, 2009;Jean-Richard-Dit-Bressel et al, 2019;Bravo-Rivera et al, 2021), reversal learning (Bari et al, 2010), or variations in reward probability (Ainslie, 1975;St Onge and Floresco, 2009;Dellu-Hagedorn et al, 2018), although the neural mechanisms underlying such differences are less clear. Evidence indicates that some of the neurobiological bases of individual variation in stimulus-reward response depend on differences in dopamine levels in subcortical circuits (Tomie et al, 2000;Flagel et al, 2007;Flagel et al, 2011), which are regulated by top-down mechanisms involving the mPFC (Ferenczi et al, 2016;Haight et al, 2017;Serrano-Barroso et al, 2019).…”

Sex divergent behavioral responses in platform-mediated avoidance and glucocorticoid receptor blockade

“…Notably, male and female rats have been previously used in PMA but displayed similar behavioral phenotypes (Bravo-Rivera, et al, 2021). Across all experiments, in our three-day training procedure, 83.8% of male mice avoided shock on the third day and met the training criterion to proceed with the extinction phase of the experiment.…”

Measuring maladaptive avoidance: from animal models to clinical anxiety

“…This task has been further modified to maximize competition between avoidance and reward by presenting the lever for reward only during presentation of the tone that signals impending shock. There were individual differences in avoidance tendency such that rats that preferred avoidance had increased amygdala activity compared to rats that preferred reward approach, which had decreased prefrontal activity [79]. The "risk-reward interaction" task [60] also adds an element of reward into a traditional shuttle box style apparatus, such that each chamber contains a shock floor and a reward port.…”