Representation of reinforcement signals in the neocortex by vasoactive intestinal polypeptide-expressing interneurons
Szadai Zoltán
János Szentágothai Neurosciences
Dr. Bereczki Dániel
HUN-REN KOKI előadóterem
2026-04-23 14:00:00
Functional neurosciences
Dr. Sperlágh Beáta
Dr. Rózsa Balázs
Dr. Réthelyi János
Dr. Fiáth Richárd
Dr. Alpár Alán
Dr. Hádinger Nóra
Dr. Szigeti Krisztián
One of the proposed functions of the cerebral cortex is the generation of complex models of the external world, which are then utilized to predict future events. These models may include information related to the impact of forthcoming events on the life prospects of living beings. Despite the critical importance of this function, the precise biological mechanisms underlying it remain obscure. In my experiments, I attempted to simulate these events with a particular emphasis on identifying the cell types and signaling pathways implicated in the cortical representation of reward and punishment. For this purpose, I employed a custom-developed 2-photon microscope with acousto-optical deflectors and special scanning modes. This advanced imaging technique allowed for the precise scanning of a sparse interneuron population, the vasoactive intestinal polypeptide (VIP) -containing interneurons. The activity of the cells was monitored with virally transfected genetically encoded calcium indicators while mice were engaged in a series of auditory discrimination tasks. In these tasks, the animals received rewards either unpredictably or in response to specific stimuli, or following a training period, they could trigger rewards through appropriate behavior. The interneurons demonstrated varied responses to the rewards and cues, and the amplitude of the response to rewards was modulated by reward expectation, distinguishable from the recruitment caused by arousal and locomotion. The reward response did not influence the cells' participation in local sensory processing. The global response pattern observed in cortical VIP interneurons indicates a specialized, cell-type-specific mechanism that enables the modulation of local neural circuitry and plasticity by integrating broader, organism-level reinforcement signals. This finding opens new avenues for understanding the complex interplay between global and local neuronal processes and their impact on learning and behavior.
