title: Follow your nose: Implicit spatial processing within the chemosensory systems.
abstract: Although most studies agree that humans cannot smell in stereo, it was recently suggested that olfactory localization is possible when assessed implicitly. In a spatial cueing paradigm, lateralized olfactory cues impaired the detection of congruently presented visual targets, an effect contrary to the typical facilitation observed in other sensory domains. Here, we examined the specificity and the robustness of this finding by studying implicit localization abilities in another chemosensory system and by accounting for possible confounds in a modified paradigm. Sixty participants completed a spatial cueing task along with an explicit localization task, using trigeminal (Experiment 1) and olfactory (Experiment 2) stimuli. A control task was implemented to control for residual somatosensory stimulation (Experiment 3). In the trigeminal experiment, stimuli were localized with high accuracy on the explicit level, while the cueing effect in form of facilitation was limited to response accuracy. In the olfactory experiment, responses were slowed by congruent cues on the implicit level, while no explicit localization was observed. Our results point to the robustness of the olfactory interference effect, corroborating the implicit-explicit dissociation of olfactory localization, and challenging the view that humans lost the ability to extract spatial information from smell. The absence of a similar interference for trigeminal cues suggests distinct implicit spatial processing mechanisms within the chemosensory systems. Moreover, the lack of a typical facilitation effect in the trigeminal domain points to important differences from spatial information processing in other, nonchemosensory domains. The possible mechanisms driving the effects are discussed. (PsycINFO Database Record
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University.
authors.forename: Olga A
authors.initials: OA
authors.lastname: Wudarczyk
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University.
authors.forename: Ute
authors.initials: U
authors.lastname: Habel
authors.affiliation: Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania.
authors.forename: Bruce I
authors.initials: BI
authors.lastname: Turetsky
authors.affiliation: Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania.
authors.forename: Raquel E
authors.initials: RE
authors.lastname: Gur
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University.
authors.forename: Thilo
authors.initials: T
authors.lastname: Kellermann
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University.
authors.forename: Frank
authors.initials: F
authors.lastname: Schneider
authors.affiliation: Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, University of Mannheim/ Heidelberg.
authors.forename: Carolin
authors.initials: C
authors.lastname: Moessnang
mesh_terms: D000328:Adult; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D055696:Olfactory Perception / Q000502:physiology*; D017603:Signal Detection, Psychological / Q000502:physiology*; D065855:Spatial Processing / Q000528:radiation effects*; D014276:Trigeminal Nerve; D055815:Young Adult