title: LTP-like plasticity in the visual system and in the motor system appear related in young and healthy subjects.
abstract: LTP-like plasticity measured by visual evoked potentials (VEP) can be induced in the intact human brain by presenting checkerboard reversals. Also associated with LTP-like plasticity, around two third of participants respond to transcranial magnetic stimulation (TMS) with a paired-associate stimulation (PAS) protocol with a potentiation of their motor evoked potentials. LTP-like processes are also required for verbal and motor learning tasks. We compared effect sizes, responder rates and intercorrelations as well as the potential influence of attention between these four assessments in a group of 37 young and healthy volunteers. We observed a potentiation effect of the N75 and P100 VEP component which positively correlated with plasticity induced by PAS. Subjects with a better subjective alertness were more likely to show PAS and VEP potentiation. No correlation was found between the other assessments. Effect sizes and responder rates of VEP potentiation were higher compared to PAS. Our results indicate a high variability of LTP-like effects and no evidence for a system-specific nature. As a consequence, studies wishing to assess individual levels of LTP-like plasticity should employ a combination of multiple assessments.
authors.affiliation: Center of Geriatrics and Gerontology Freiburg, University Medical Center Freiburg Freiburg, Germany ; Department of Neurology, Freiburg Brain Imaging, University Medical Center Freiburg Freiburg, Germany ; Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany ; Department of Neurology, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Klöppel
authors.affiliation: Department of Neurology, Freiburg Brain Imaging, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Eliza
authors.initials: E
authors.lastname: Lauer
authors.affiliation: Department of Neurology, Freiburg Brain Imaging, University Medical Center Freiburg Freiburg, Germany ; Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany ; Department of Neurology, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Jessica
authors.initials: J
authors.lastname: Peter
authors.affiliation: Department of Neurology, Freiburg Brain Imaging, University Medical Center Freiburg Freiburg, Germany ; Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany ; Laboratory for Biological and Personality Psychology, Department of Psychology, University of Freiburg Freiburg, Germany.
authors.forename: Lora
authors.initials: L
authors.lastname: Minkova
authors.affiliation: Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Nissen
authors.affiliation: Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Normann
authors.affiliation: Department of Neurology, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Janine
authors.initials: J
authors.lastname: Reis
authors.affiliation: Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany ; Department of Pediatrics, Kinderzentrum München gGmbH, Technical University Munich Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Mainberger
authors.affiliation: Eye Center, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Bach
authors.affiliation: Department of Neurology, Freiburg Brain Imaging, University Medical Center Freiburg Freiburg, Germany ; Department of Psychiatry and Psychotherapy, University Medical Center Freiburg Freiburg, Germany ; Department of Neurology, University Medical Center Freiburg Freiburg, Germany.
authors.forename: Jacob
authors.initials: J
authors.lastname: Lahr
keywords: LTP-like plasticity; VEP potentiation; long-term potentiation (LTP); motor learning; neuroplasticity; paired associative stimulation (PAS); verbal learning