CONTEXTUAL TASK SWITCHING WITHIN FRONTAL-HIPPOCAMPAL CIRCUITRY

Flexible behaviour requires animals to integrate knowledge about environmental structure with internal goals, and to adjust behaviour when task demands change. Recent work has shown that medial frontal cortex (mFC) maps behavioural structure within fixed task structures, and that ventral hippocampus (vHPC) represents hidden state inference. Yet it remains unclear how these representations adapt when the task structure itself changes and how contextual cues can guide this process.

To address this, we trained mice on two abstract goal-sequencing task structures in a 3×3 maze while recording from both mFC and vHPC. In a tone-cued “AB” task, animals obtained rewards in a repeating sequence of two locations (…a-b-a-b-a…), whereas in an uncued “ABC” task, the sequence comprises three locations (…a-b-c-a-b-c-a…). Physical reward locations changed across tasks, allowing abstract structure to be dissociated from spatial structure.

Our preliminary behavioural results indicate that mice can use the contextual cue to flexibly adjust their behaviour and permit inference of an unseen task transition, returning to the start location after two rewards in the AB task and after three rewards in the ABC task. Ongoing analyses of simultaneously recorded neural populations will test whether persistent contextual signals are present in mFC or vHPC and how the alternative task structures are represented and selected across these regions. Here, we have introduced a novel paradigm for examining how frontal–hippocampal circuits support flexible behaviour across changing task contexts.