title: Age effects in storage and extinction of a naturally acquired conditioned eyeblink response.
abstract: Acquisition of conditioned eyeblink responses is known to decline with age, and age-related decline has been related to a reduction of cerebellar size and function. The aim of the present study was to investigate age-related effects on storage-related processes and extinction of visual threat eyeblink responses (VTERs), conditioned responses which are naturally acquired in early childhood. Storage and extinction of VTERs were tested in 34 healthy participants with an age range from 21 to 74 years (mean age 41.6±16.3 years). High-resolution structural magnetic resonance images (MRI) were acquired in all subjects. Conventional volumetric measures and voxel-based morphometry (VBM) were performed at the level of the cerebellum. Storage and extinction of VTERs showed a significant age-dependent decline. Likewise, cerebellar volume decreased with age. Storage, but not extinction showed a significant positive correlation with age-dependent reduction of total cerebellar volume. VBM analysis showed that gray matter volume in circumscribed areas of intermediate lobules VI, and Crus I and II bilaterally were positively correlated with VTER storage (p<0.05, FWE corrected). Considering extinction, no significant correlations with gray matter cerebellar volume were observed. The present findings show that reduction of storage of learned eyeblink responses with age is explained at least in part by age-dependent decline of cerebellar function. Future studies need to be performed to better understand which brain areas contribute to age-dependent reduction of extinction.
authors.affiliation: Department of Neurology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Thürling
authors.affiliation: Department of Neurology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Galuba
authors.affiliation: Department of Neurology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Thieme
authors.affiliation: Department of Neurology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: R G
authors.initials: RG
authors.lastname: Burciu
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Göricke
authors.affiliation: Department of Computer Sciences, University of Düsseldorf, Düsseldorf, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Beck
authors.affiliation: Department of Neurology, MediClin Fachklinik Rhein/Ruhr, Essen, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Wondzinski
authors.affiliation: Department of Neurology, MediClin Fachklinik Rhein/Ruhr, Essen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Siebler
authors.affiliation: Department of Neurology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Gerwig
authors.affiliation: Department of Biomedical Sciences, Iowa State University, Ames, IA, USA.
authors.forename: V
authors.initials: V
authors.lastname: Bracha
authors.affiliation: Department of Neurology, University Clinic Essen, University of Duisburg-Essen, Essen, Germany. Electronic address: dagmar.timmann-braun@uni-due.de.
authors.forename: D
authors.initials: D
authors.lastname: Timmann
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002531:Cerebellum / Q000033:anatomy & histology*; D003215:Conditioning, Eyelid / Q000502:physiology*; D005108:Extinction, Psychological / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: Associative learning; Cerebellum; Extinction; Eyeblink; Human; Storage; Visual threat