title: Sound-induced modulation of hippocampal θ oscillations.
abstract: The mechanism of response of hippocampal neurons to a specific feature in sensory stimuli is not fully understood, although the hippocampus is well known to contribute to the formation of episodic memory in the multisensory world. Using in-vivo voltage-clamp recordings from awake mice, we found that sound pulses induced a transient increase in inhibitory, but not excitatory, conductance in hippocampal CA1 pyramidal cells. In local field potentials, sound pulses induced a phase resetting of the θ oscillations, one of the major oscillatory states of the hippocampus. Repetitive sound pulses at 7 Hz (θ rhythm) increased the θ oscillation power, an effect that was abolished by a surgical fimbria-fornix lesion. Thus, tone-induced inhibition is likely of subcortical origin. It may segment hippocampal neural processing and render temporal boundaries in continuously ongoing experiences.
authors.affiliation: aLaboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo bLaboratory for Advanced Brain Signal Processing, RIKEN Brain Science Institute, Saitama cCenter for Information and Neural Networks, Osaka, Japan.
authors.forename: Reimi
authors.initials: R
authors.lastname: Abe
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Sakaguchi
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kitajo
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ishikawa
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Matsumoto
authors.forename: Norio
authors.initials: N
authors.lastname: Matsuki
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ikegaya
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001307:Auditory Perception / Q000502:physiology*; D056547:CA1 Region, Hippocampal / Q000502:physiology*; D020712:Fornix, Brain / Q000503:physiopathology; D008297:Male; D008813:Mice, Inbred ICR; D009433:Neural Inhibition / Q000502:physiology*; D009434:Neural Pathways / Q000503:physiopathology; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000502:physiology*; D013826:Theta Rhythm / Q000502:physiology*