title: Dynamics of dendritic spines in the mouse auditory cortex during memory formation and memory recall.
abstract: Long-lasting changes in synaptic connections induced by relevant experiences are believed to represent the physical correlate of memories. Here, we combined chronic in vivo two-photon imaging of dendritic spines with auditory-cued classical conditioning to test if the formation of a fear memory is associated with structural changes of synapses in the mouse auditory cortex. We find that paired conditioning and unpaired conditioning induce a transient increase in spine formation or spine elimination, respectively. A fraction of spines formed during paired conditioning persists and leaves a long-lasting trace in the network. Memory recall triggered by the reexposure of mice to the sound cue did not lead to changes in spine dynamics. Our findings provide a synaptic mechanism for plasticity in sound responses of auditory cortex neurons induced by auditory-cued fear conditioning; they also show that retrieval of an auditory fear memory does not lead to a recapitulation of structural plasticity in the auditory cortex as observed during initial memory consolidation.
authors.affiliation: Research Institute of Molecular Pathology, 1030 Vienna, Austria.
authors.forename: Kaja Ewa
authors.initials: KE
authors.lastname: Moczulska
authors.forename: Juliane
authors.initials: J
authors.lastname: Tinter-Thiede
authors.forename: Manuel
authors.initials: M
authors.lastname: Peter
authors.forename: Lyubov
authors.initials: L
authors.lastname: Ushakova
authors.forename: Tanja
authors.initials: T
authors.lastname: Wernle
authors.forename: Brice
authors.initials: B
authors.lastname: Bathellier
authors.forename: Simon
authors.initials: S
authors.lastname: Rumpel
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D003213:Conditioning, Psychological / Q000502:physiology; D049229:Dendritic Spines / Q000502:physiology*; D005239:Fear / Q000502:physiology; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology*; D051379:Mice; D008856:Microscopy, Fluorescence; D016133:Polymerase Chain Reaction; D013569:Synapses / Q000502:physiology*
keywords: auditory fear conditioning; learning; reconsolidation