M. Wolff et al in Elife

A thalamocortical circuit for updating action-outcome associations.
Fresno V, Parkes SL, Faugère A, Coutureau E, Wolff M.
Elife. 2019 Apr 23;8. pii: e46187. doi: 10.7554/eLife.46187.

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The ability to flexibly use knowledge is one cardinal feature of goal-directed behaviors. The DECAD team recently showed that thalamocortical and corticothalamic pathways connecting the medial prefrontal cortex and the mediodorsal thalamus (MD) contribute to adaptive decision-making (Alcaraz et al., 2018]). In this study, the team examined the impact of disconnecting the MD from its other main cortical target, the orbitofrontal cortex (OFC) in a task assessing outcome devaluation after initial instrumental training and after reversal of action-outcome contingencies. Crossed MD and OFC lesions did not impair instrumental performance. In sharp contrast, disconnecting the OFC from its other main thalamic afferent, the submedius nucleus, produced a specific impairment in adaptive responding following action-outcome reversal. Altogether, this suggests that multiple thalamocortical circuits may act synergistically to achieve behaviorally relevant functions and confirm a prominent role for the cognitive thalamus in shaping mental representations.