 Recent experiments have established that the direct and indirect pathways of the dorsal striatum are not solely involved in movement.Initial experiments in an intracranial self-stimulation paradigm suggested opposing roles in reinforcement for the two pathways; specifically, stimulation of direct pathway medium spiny neurons was found to be reinforcing, whereas stimulation of indirect pathway medium spiny neurons was aversive.However, a subsequent study (using more physiologically relevant stimulation parameters) found that direct and indirect pathway stimulation was reinforcing, but that pathway-specific stimulation resulted in the development of different action strategies.