title: Functional magnetic resonance imaging of a human auditory cortex area involved in foreground-background decomposition.
abstract: Auditory foreground-background decomposition is a pattern recognition process which combines simultaneous and sequential grouping in complex sound sequences. Using functional magnetic resonance imaging with reduced scanner noise and stimulation through a new type of earphones, we investigated the possibility that this process activates topographically distinct areas of human auditory cortex. A basic matching-to-sample task with variable tones (sequential grouping) caused significant activity in three separate landmark-related territories on the supratemporal plane. A similar task in the presence of a strongly masking acoustic background pattern to challenge simultaneous grouping led to the distinction of the subterritory in which foreground signal-related or task-related signal properties were exclusively seen. In contrast to the remainder of territories the level of activity and the periodicity of the signal time-course was resistant to the masking influence of the background. This suggests that auditory foreground-background decomposition involves a specialized non-primary auditory cortex field. Generally, the findings demonstrate functional parcellation of auditory cortex for which the evidence in humans, in contrast to other primates, is only indirect to date.
authors.affiliation: Federal Institute for Neurobiology, Magdeburg, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Scheich
authors.forename: F
authors.initials: F
authors.lastname: Baumgart
authors.forename: B
authors.initials: B
authors.lastname: Gaschler-Markefski
authors.forename: C
authors.initials: C
authors.lastname: Tegeler
authors.forename: C
authors.initials: C
authors.lastname: Tempelmann
authors.forename: H J
authors.initials: HJ
authors.lastname: Heinze
authors.forename: F
authors.initials: F
authors.lastname: Schindler
authors.forename: D
authors.initials: D
authors.lastname: Stiller
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology*; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male