Emerging insights in human brain and behavior from intracranial recordings

Abstract

Human behavior depends on a collection of cognitive capacities that are expressed with complexity in humans. Although animal models have been essential for identifying fundamental neural mechanisms, many aspects of human cognition require direct investigation in the human brain. Studies of social decision-making, communication, and spatial navigation increasingly rely on intracranial electrophysiology to probe the neural basis. Related to these topics, reward processing warrants emphasis. It is not uniquely human, but it provides a central organizing signal linking motivation, learning, emotion, and choice across many human behaviors. Disruptions of reward circuits are a hallmark of numerous neurological and psychiatric conditions, giving this domain specific relevance for patient care. Fifteen studies published between 2009 and 2024 used human intracranial recordings to examine reward-related processes, nearly all in patients undergoing invasive monitoring for drug-resistant epilepsy. These studies investigated 17 neocortical and subcortical regions, most frequently the orbitofrontal cortex, using intracranial EEG, deep brain stimulation, and single-unit recordings. Recent work increasingly incorporates social interactions and computational models of learning. The purpose of this narrative review is to provide an overview of human reward processing, emphasizing how intracranial recordings have clarified the neural circuits that underlie a range of human cognitive capacities. Beyond advancing basic neuroscience, intracranial electrophysiology can inform circuit-guided interventions for neurological and psychiatric disorders.

Keywords

intracranial electrophysiology / human brain / cognition / reward processing / learning

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