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Frontostriatal circuits are neural pathways that connect frontal lobe regions with the basal ganglia (striatum) that mediate motor, cognitive, and behavioural functions within the brain. They receive inputs from dopaminergic, serotonergic, noradrenergic, and cholinergic cell groups that modulate information processing. Frontostriatal circuits are part of the executive functions. These circuits are involved in neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease as well as neuropsychiatric disorders including schizophrenia, depression, obsessive compulsive disorder (OCD), and attention-deficit hyperactivity disorder (ADHD).

Anatomy
There are five defined frontostriatal circuits: motor and oculomotor circuits originating in the frontal eye fields are involved in motor functions; while dorsolateral prefrontal, orbital frontal, and anterior cingulate circuits are involved in executive functions, social behavior and motivational states. These five circuits share same anatomical structures. These circuits originate in prefrontal cortex and project to the striatum followed by globus pallidus and substantia nigra and finally to the thalamus. There are also feedback loops from thalamus back to prefrontal cortex completing the closed loop circuits. Also, there are open connections to these circuits integrating information from other areas of the brain.

Function
The role of frontostriatal circuits is not well understood. Two of the common theories are action selection and reinforcement learning. The action selection hypothesis suggest that frontalcortex generates possible actions and the striatum selects one of these actions by inhibiting the execution of other actions while allowing the selected action execution. Whereas, the reinforcement learning hypothesis suggest that prediction errors are used to update future reward expectations for selected actions and this guides the selection of actions based on reward expectations.

The ventromedial prefrontal cortex and its connections to ventral striatum and amygdala are important in affective-emotional processing. They are responsible for elaboration of the plan of actions responsible for goal-directed behavior.