Shifts in decision making under approach-avoidance conflict play a central role in neuropsychiatric disorders, where biases towards avoidance [(e.g. anxiety, obsessive compulsive disorder (OCD)] or approach (substance use disorder) can manifest.  In OCD, compulsive behaviours can be conceptualized as avoidance responses aimed to avoid the negative outcomes associated with the patient's obsessions, and therefore understanding how excessive avoidance can manifest and be extinguished may be helpful for understanding OCD and developing new treatments.

The platform avoidance task was developed in rats to study avoidance learning, approach avoidance conflict, and avoidance extinction, including extinction with response prevention relevant to the leading cognitive behavioural therapy for OCD. We are using this task to understand behavioural changes in an OCD mouse model and neurobiological mechanisms. 

First, study 1 examined sex differences in approach avoidance conflict, given the extensive literature on sex differences in defensive behaviour across a variety of tasks. Study 2 describes changes in approach-avoidance conflict in a preclinical mouse model of OCD, Sapap3 knockout mice. Finally, study 3 will share preliminary data on effects of drugs targeting serotonin 5HT2C receptors, as 5HT2C receptors mediate the effects of first-line OCD antidepressant treatments on striatal dopamine, which is critical for expression of avoidance behaviour.

Together these studies highlight how the platform avoidance task can be used to study basic and maladaptive mechanisms of approach-avoidance conflict, and uncover mechanisms relevant to disrupted avoidance behaviour in OCD.