title: Dopamine signaling as a neural correlate of consciousness.
abstract: The neural correlates of consciousness are largely unknown but many neural circuits are likely to be involved. Our experiments with mice that cannot synthesize dopamine suggest that dopamine signaling is a critical component necessary for the expression of consciousness. Although dopamine-deficient mice are awake and respond to many stimuli, they are unmotivated and have profound deficits in all but the simplest learning tasks. Dopamine-deficient mice are unable to attend to salient sensory information, integrate it with prior experience, store it in long-term memory, or choose appropriate actions. While clearly conscious from a general anesthetic point of view, dopamine-deficient mice have marginal arousal and appear to be virtually unconscious from a behavioral point of view. Restoration of dopamine signaling within the striatum by viral gene therapy strategies restores most behaviors. Therefore, I propose that dopaminergic modulation of glutamatergic inputs from the cortex and thalamus onto medium spiny neurons in the striatum contributes to cognition and the expression of consciousness.
authors.affiliation: Howard Hughes Medical Institute and Department of Biochemistry, University of Washington, Seattle, WA 98195, USA. palmiter@uw.edu
authors.forename: R D
authors.initials: RD
authors.lastname: Palmiter
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology / Q000502:physiology; D003071:Cognition / Q000502:physiology; D003243:Consciousness / Q000502:physiology*; D004298:Dopamine / Q000172:deficiency / Q000378:metabolism*; D006801:Humans; D051379:Mice; D009474:Neurons / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D004298:Dopamine