title: Olfactory short-term memory encoding and maintenance - an event-related potential study.
abstract: This study examined whether the memory encoding and short term maintenance of olfactory stimuli is associated with neurophysiological activation patterns which parallel those described for sensory modalities such as vision and auditory. We examined olfactory event-related potentials in an olfactory change detection task in twenty-four healthy adults and compared the measured activation to that found during passive olfactory stimulation. During the early olfactory post-processing phase, we found a sustained negativity over bilateral frontotemporal areas in the passive perception condition which was enhanced in the active memory task. There was no significant lateralization in either experimental condition. During the maintenance interval at the end of the delay period, we still found sustained activation over bilateral frontotemporal areas which was more negative in trials with correct - as compared to incorrect - behavioural responses. This was complemented by a general significantly stronger frontocentral activation. Summarizing, we were able to show that olfactory short term memory involves a parallel sequence of activation as found in other sensory modalities. In addition to olfactory-specific frontotemporal activations in the memory encoding phase, we found slow cortical potentials over frontocentral areas during the memory maintenance phase indicating the activation of a supramodal memory maintenance system. These findings could represent the neurophysiological underpinning of the 'olfactory flacon', the olfactory counter-part to the visual sketchpad and phonological loop embedded in Baddeley's working memory model.
authors.affiliation: Department of Child and Adolescent Psychiatry, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Lenk
authors.affiliation: Department of Child and Adolescent Psychiatry, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Annet
authors.initials: A
authors.lastname: Bluschke
authors.affiliation: Department of Child and Adolescent Psychiatry, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Beste
authors.affiliation: Department of Otorhinolaryngologyx, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Emilia
authors.initials: E
authors.lastname: Iannilli
authors.affiliation: Department of Child and Adolescent Psychiatry, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Veit
authors.initials: V
authors.lastname: Rößner
authors.affiliation: Department of Otorhinolaryngologyx, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hummel
authors.affiliation: Department of Child and Adolescent Psychiatry, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Department of Child and Adolescent Psychiatry, Johann-Wolfgang-Goethe Universität, Frankfurt, Germany. Electronic address: Stephan.Bender@kgu.de.
authors.forename: Stephan
authors.initials: S
authors.lastname: Bender
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D004569:Electroencephalography; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D055696:Olfactory Perception / Q000502:physiology*; D055815:Young Adult
keywords: Hemispheric lateralisation; Odour memory; Olfactory event-related potentials; Olfactory processing; Short-term memory; Slow cortical potentials