Cognitive experience alters cortical involvement in goal-directed navigation

Neural activity in the mammalian cortex has been studied extensively during decision tasks, and recent work aims to identify under what conditions cortex is actually necessary for these tasks. We studied whether cognitive experience, beyond sensory or motor learning, affects cortical involvement in goal-directed navigation. To this aim, we first trained different cohorts of mice on either a simple goal-directed navigation task (“simple task”), or one of two complex tasks involving delay periods (“delay task”) or rule reversals (“switching task”) in virtual reality. After task learning, we optogenetically inhibited various cortical areas on a subset of trials while mice performed a given task to assess the necessity of each area for task performance. We found overall minor cortical necessity for the simple task, but large necessity of cortical association areas (specifically of posterior parietal cortex and retrosplenial cortex) for each complex task. We then permanently transitioned mice with complex task experience to the simple task, again inhibiting cortical areas on a subset of trials. Crucially, we found that these mice heavily relied on cortical association areas for simple task performance, unlike mice without prior complex task experience. Therefore, past experience is a key factor in determining whether cortical areas have a causal role in goal-directed navigation.

In this dataset, we include both behavioral data for the initial task training period, as well as behavioral data for all subsequent optogenetic inhibition experiments. Details about the data structure are available in the accompanying Readme.txt files.

Methods
Transgenic mice expressing Channelrhodopsin in GABAergic cortical interneurons were trained in a goal-directed virtual visual navigation task (simple task, delay task, or switching task), and optogenetic inhibition was performed on a subset of behavioral trials, with each trial containing one of the following inhibition targets: posterior parietal cortex, retrosplenial cortex, somatosensory cortex, anterior cingulate cortex / secondary motor cortex, or a control spot. Virtual reality environments were operated and behavioral data were acquired in ViRMEn (Virtual Reality Mouse Engine, Aronov and Tank, 2014). Photoinhibition was controlled and inhibition parameters were saved by a separate computer using MATLAB.