In the cerebral cortex the concerted activity of neuronal ensembles enables higher cognitive functions. The hippocampus encodes spatial and episodic memory and sends this information to the prefrontal cortex to guide decisions on behavioural action. In the medial prefrontal cortex and hippocampus single neurons, the identity of which are unknown, exhibit specific firing patterns during the execution of different behaviours and simple decisions like turning left or right in a maze. However, the cortex contains a rich diversity of neuronal populations, which are defined by distinct connectivity, molecular expression profile and contribution to network activity. Thus, in order to discover neuronal circuits underlying learning, memory and decision making, it is critical to verify the identity of the recorded neurons or manipulate the activity of specific neuronal types.
In the present research programme we record the activity of identified neurons in the medial prefrontal cortex and hippocampus during memory and decision-making tasks, for example during a matching-to-place task on a continuous T-Maze. Such tasks require to keep the information about the direction in the previous lap in the working memory, to learn a new task rule and based on this information make an executive decision. In this research programme we determine how different neurons and neuronal ensembles in the hippocampus and prefrontal cortex contribute to cognitive tasks.
Overall, this research programme aims to define specific neuronal circuits supporting memory and decision making, which are impaired in pathological conditions like schizophrenia.