Quite often you hear people say that the prefrontal cortex (PFC) is key for planning, and that because of the different way the PFC works with adolescents is the reason they often are bad at planning. But maybe we need to change the textbooks, because as always it’s a bit more complicated than that. Cue this new study by Vikbladh et al published in Neuron, that shows that the hippocampus also plays a role.
The summary of the study:
Little is known about the neural mechanisms that allow humans and animals to plan actions using knowledge of task contingencies. Emerging theories hypothesize that it involves the same hippocampal mechanisms that support self-localization and memory for locations. Yet limited direct evidence supports the link between planning and the hippocampal place map. We addressed this by investigating model-based planning and place memory in healthy controls and epilepsy patients treated using unilateral anterior temporal lobectomy with hippocampal resection. Both functions were impaired in the patient group. Specifically, the planning impairment was related to right hippocampal lesion size, controlling for overall lesion size. Furthermore, although planning and boundary-driven place memory covaried in the control group, this relationship was attenuated in patients, consistent with both functions relying on the same structure in the healthy brain. These findings clarify both the neural mechanism of model-based planning and the scope of hippocampal contributions to behavior.