ReviewDopaminergic impact on local and global cortical circuit processing during learning

- Dopamine impacts on cortical circuit processing in a layer-dependent manner.
- Dopamine-modulated corticoefferent feedback gain promotes sensory input processing.
- Local cortical dopamine actions broadcast to global corticocortical circuits.
- Such circuit functions assist the integration of bottom-up and top-down information.
- Cortical dopamine is a multifunction signal in the service of behavioral adaptation.

We have learned to detect, predict and behaviorally respond to important changes in our environment on short and longer time scales. Therefore, brains of humans and higher animals build upon a perceptual and semantic salience stored in their memories mainly generated by associative reinforcement learning. Functionally, the brain needs to extract and amplify a small number of features of sensory input with behavioral relevance to a particular situation in order to guide behavior. In this review, I argue that dopamine action, particularly in sensory cortex, orchestrates layer-dependent local and long-range cortical circuits integrating sensory associated bottom-up and semantically relevant top-down information, respectively. Available evidence reveals that dopamine thereby controls both the selection of perceptually or semantically salient signals as well as feedback processing from higher-order areas in the brain. Sensory cortical dopamine thereby governs the integration of selected sensory information within a behavioral context. This review proposes that dopamine enfolds this function by temporally distinct actions on particular layer-dependent local and global cortical circuits underlying the integration of sensory, and non-sensory cognitive and behavioral variables.

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