title: Right orbitofrontal cortex mediates conscious olfactory perception.
abstract: Understanding how the human brain translates sensory impressions into conscious percepts is a key challenge of neuroscience research. Work in this area has overwhelmingly centered on the conscious experience of vision at the exclusion of the other senses--in particular, smell. We hypothesized that the orbitofrontal cortex (OFC) is a central substrate for olfactory conscious experience because of its privileged physiological role in odor processing. Combining functional magnetic resonance imaging, peripheral autonomic recordings, and olfactory psychophysics, we studied a case of complete anosmia (smell loss) in a patient with circumscribed traumatic brain injury to the right OFC. Despite a complete absence of conscious olfaction, the patient exhibited robust "blind smell," as indexed by reliable odor-evoked neural activity in the left OFC and normal autonomic responses to odor hedonics during presentation of stimuli to the left nostril. These data highlight the right OFC's critical role in subserving human olfactory consciousness.
authors.affiliation: Department of Psychology, University of Wisconsin-Madison, Madison, WI 53706, USA. wenli@psych.wisc.edu
authors.forename: Wen
authors.initials: W
authors.lastname: Li
authors.forename: Leonardo
authors.initials: L
authors.lastname: Lopez
authors.forename: Jason
authors.initials: J
authors.lastname: Osher
authors.forename: James D
authors.initials: JD
authors.lastname: Howard
authors.forename: Todd B
authors.initials: TB
authors.lastname: Parrish
authors.forename: Jay A
authors.initials: JA
authors.lastname: Gottfried
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology*; D001341:Autonomic Nervous System / Q000503:physiopathology; D001364:Awareness / Q000502:physiology*; D001930:Brain Injuries / Q000503:physiopathology / Q000523:psychology; D004292:Dominance, Cerebral / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology; D005625:Frontal Lobe / Q000293:injuries / Q000503:physiopathology*; D005712:Galvanic Skin Response / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D000857:Olfaction Disorders / Q000503:physiopathology* / Q000523:psychology; D011601:Psychophysics; D012016:Reference Values; D056152:Respiratory Rate / Q000502:physiology; D012903:Smell / Q000502:physiology*
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