---
_id: '1919'
abstract:
- lang: eng
  text: Long-lasting memories are formed when the stimulus is temporally distributed
    (spacing effect). However, the synaptic mechanisms underlying this robust phenomenon
    and the precise time course of the synaptic modifications that occur during learning
    remain unclear. Here we examined the adaptation of horizontal optokinetic response
    in mice that underwent 1 h of massed and spaced training at varying intervals.
    Despite similar acquisition by all training protocols, 1 h of spacing produced
    the highest memory retention at 24 h, which lasted for 1 mo. The distinct kinetics
    of memory are strongly correlated with the reduction of floccular parallel fiber-Purkinje
    cell synapses but not with AMPA receptor (AMPAR) number and synapse size. After
    the spaced training, we observed 25%, 23%, and 12% reduction in AMPAR density,
    synapse size, and synapse number, respectively. Four hours after the spaced training,
    half of the synapses and Purkinje cell spines had been eliminated, whereas AMPAR
    density and synapse size were recovered in remaining synapses. Surprisingly, massed
    training also produced long-term memory and halving of synapses; however, this
    occurred slowly over days, and the memory lasted for only 1 wk. This distinct
    kinetics of structural plasticity may serve as a basis for unique temporal profiles
    in the formation and decay of memory with or without intervals.
acknowledgement: his work was supported by Solution Oriented Research for Science
  and Technology (R.S.), Core Research for Evolutional Science and Technology, Japan
  Science and Technology Agency (Y.F.), and Grants-in-Aid for Scientific Research
  on Priority Areas-Molecular Brain Sciences 16300114 (to R.S.) and 18022043 (to Y.F.).
author:
- first_name: Wajeeha
  full_name: Aziz, Wajeeha
  last_name: Aziz
- first_name: Wen
  full_name: Wang, Wen
  last_name: Wang
- first_name: Sebnem
  full_name: Kesaf, Sebnem
  id: 401AB46C-F248-11E8-B48F-1D18A9856A87
  last_name: Kesaf
- first_name: Alsayed
  full_name: Mohamed, Alsayed
  last_name: Mohamed
- first_name: Yugo
  full_name: Fukazawa, Yugo
  last_name: Fukazawa
- first_name: Ryuichi
  full_name: Shigemoto, Ryuichi
  id: 499F3ABC-F248-11E8-B48F-1D18A9856A87
  last_name: Shigemoto
  orcid: 0000-0001-8761-9444
citation:
  ama: Aziz W, Wang W, Kesaf S, Mohamed A, Fukazawa Y, Shigemoto R. Distinct kinetics
    of synaptic structural plasticity, memory formation, and memory decay in massed
    and spaced learning. <i>PNAS</i>. 2014;111(1):E194-E202. doi:<a href="https://doi.org/10.1073/pnas.1303317110">10.1073/pnas.1303317110</a>
  apa: Aziz, W., Wang, W., Kesaf, S., Mohamed, A., Fukazawa, Y., &#38; Shigemoto,
    R. (2014). Distinct kinetics of synaptic structural plasticity, memory formation,
    and memory decay in massed and spaced learning. <i>PNAS</i>. National Academy
    of Sciences. <a href="https://doi.org/10.1073/pnas.1303317110">https://doi.org/10.1073/pnas.1303317110</a>
  chicago: Aziz, Wajeeha, Wen Wang, Sebnem Kesaf, Alsayed Mohamed, Yugo Fukazawa,
    and Ryuichi Shigemoto. “Distinct Kinetics of Synaptic Structural Plasticity, Memory
    Formation, and Memory Decay in Massed and Spaced Learning.” <i>PNAS</i>. National
    Academy of Sciences, 2014. <a href="https://doi.org/10.1073/pnas.1303317110">https://doi.org/10.1073/pnas.1303317110</a>.
  ieee: W. Aziz, W. Wang, S. Kesaf, A. Mohamed, Y. Fukazawa, and R. Shigemoto, “Distinct
    kinetics of synaptic structural plasticity, memory formation, and memory decay
    in massed and spaced learning,” <i>PNAS</i>, vol. 111, no. 1. National Academy
    of Sciences, pp. E194–E202, 2014.
  ista: Aziz W, Wang W, Kesaf S, Mohamed A, Fukazawa Y, Shigemoto R. 2014. Distinct
    kinetics of synaptic structural plasticity, memory formation, and memory decay
    in massed and spaced learning. PNAS. 111(1), E194–E202.
  mla: Aziz, Wajeeha, et al. “Distinct Kinetics of Synaptic Structural Plasticity,
    Memory Formation, and Memory Decay in Massed and Spaced Learning.” <i>PNAS</i>,
    vol. 111, no. 1, National Academy of Sciences, 2014, pp. E194–202, doi:<a href="https://doi.org/10.1073/pnas.1303317110">10.1073/pnas.1303317110</a>.
  short: W. Aziz, W. Wang, S. Kesaf, A. Mohamed, Y. Fukazawa, R. Shigemoto, PNAS 111
    (2014) E194–E202.
date_created: 2018-12-11T11:54:43Z
date_published: 2014-01-07T00:00:00Z
date_updated: 2021-01-12T06:54:04Z
day: '07'
department:
- _id: RySh
doi: 10.1073/pnas.1303317110
intvolume: '       111'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3890840/
month: '01'
oa: 1
oa_version: Submitted Version
page: E194 - E202
publication: PNAS
publication_status: published
publisher: National Academy of Sciences
publist_id: '5175'
scopus_import: 1
status: public
title: Distinct kinetics of synaptic structural plasticity, memory formation, and
  memory decay in massed and spaced learning
type: journal_article
user_id: 4435EBFC-F248-11E8-B48F-1D18A9856A87
volume: 111
year: '2014'
...
---
_id: '1920'
abstract:
- lang: eng
  text: Cerebellar motor learning is suggested to be caused by long-term plasticity
    of excitatory parallel fiber-Purkinje cell (PF-PC) synapses associated with changes
    in the number of synaptic AMPA-type glutamate receptors (AMPARs). However, whether
    the AMPARs decrease or increase in individual PF-PC synapses occurs in physiological
    motor learning and accounts for memory that lasts over days remains elusive. We
    combined quantitative SDS-digested freeze-fracture replica labeling for AMPAR
    and physical dissector electron microscopy with a simple model of cerebellar motor
    learning, adaptation of horizontal optokinetic response (HOKR) in mouse. After
    1-h training of HOKR, short-term adaptation (STA) was accompanied with transient
    decrease in AMPARs by 28% in target PF-PC synapses. STA was well correlated with
    AMPAR decrease in individual animals and both STA and AMPAR decrease recovered
    to basal levels within 24 h. Surprisingly, long-termadaptation (LTA) after five
    consecutive daily trainings of 1-h HOKR did not alter the number of AMPARs in
    PF-PC synapses but caused gradual and persistent synapse elimination by 45%, with
    corresponding PC spine loss by the fifth training day. Furthermore, recovery of
    LTA after 2 wk was well correlated with increase of PF-PC synapses to the control
    level. Our findings indicate that the AMPARs decrease in PF-PC synapses and the
    elimination of these synapses are in vivo engrams in short- and long-term motor
    learning, respectively, showing a unique type of synaptic plasticity that may
    contribute to memory consolidation.
acknowledgement: This work was supported by Solution-Oriented Research for Science
  and Technology from the Japan Science and Technology Agency; Ministry of Education,
  Culture, Sports, Science and Technology of Japan Grant 16300114 (to R.S.).
author:
- first_name: Wen
  full_name: Wang, Wen
  last_name: Wang
- first_name: Kazuhiko
  full_name: Nakadate, Kazuhiko
  last_name: Nakadate
- first_name: Miwako
  full_name: Masugi Tokita, Miwako
  last_name: Masugi Tokita
- first_name: Fumihiro
  full_name: Shutoh, Fumihiro
  last_name: Shutoh
- first_name: Wajeeha
  full_name: Aziz, Wajeeha
  last_name: Aziz
- first_name: Etsuko
  full_name: Tarusawa, Etsuko
  last_name: Tarusawa
- first_name: Andrea
  full_name: Lörincz, Andrea
  last_name: Lörincz
- first_name: Elek
  full_name: Molnár, Elek
  last_name: Molnár
- first_name: Sebnem
  full_name: Kesaf, Sebnem
  id: 401AB46C-F248-11E8-B48F-1D18A9856A87
  last_name: Kesaf
- first_name: Yunqing
  full_name: Li, Yunqing
  last_name: Li
- first_name: Yugo
  full_name: Fukazawa, Yugo
  last_name: Fukazawa
- first_name: Soichi
  full_name: Nagao, Soichi
  last_name: Nagao
- first_name: Ryuichi
  full_name: Shigemoto, Ryuichi
  id: 499F3ABC-F248-11E8-B48F-1D18A9856A87
  last_name: Shigemoto
  orcid: 0000-0001-8761-9444
citation:
  ama: Wang W, Nakadate K, Masugi Tokita M, et al. Distinct cerebellar engrams in
    short-term and long-term motor learning. <i>PNAS</i>. 2014;111(1):E188-E193. doi:<a
    href="https://doi.org/10.1073/pnas.1315541111">10.1073/pnas.1315541111</a>
  apa: Wang, W., Nakadate, K., Masugi Tokita, M., Shutoh, F., Aziz, W., Tarusawa,
    E., … Shigemoto, R. (2014). Distinct cerebellar engrams in short-term and long-term
    motor learning. <i>PNAS</i>. National Academy of Sciences. <a href="https://doi.org/10.1073/pnas.1315541111">https://doi.org/10.1073/pnas.1315541111</a>
  chicago: Wang, Wen, Kazuhiko Nakadate, Miwako Masugi Tokita, Fumihiro Shutoh, Wajeeha
    Aziz, Etsuko Tarusawa, Andrea Lörincz, et al. “Distinct Cerebellar Engrams in
    Short-Term and Long-Term Motor Learning.” <i>PNAS</i>. National Academy of Sciences,
    2014. <a href="https://doi.org/10.1073/pnas.1315541111">https://doi.org/10.1073/pnas.1315541111</a>.
  ieee: W. Wang <i>et al.</i>, “Distinct cerebellar engrams in short-term and long-term
    motor learning,” <i>PNAS</i>, vol. 111, no. 1. National Academy of Sciences, pp.
    E188–E193, 2014.
  ista: Wang W, Nakadate K, Masugi Tokita M, Shutoh F, Aziz W, Tarusawa E, Lörincz
    A, Molnár E, Kesaf S, Li Y, Fukazawa Y, Nagao S, Shigemoto R. 2014. Distinct cerebellar
    engrams in short-term and long-term motor learning. PNAS. 111(1), E188–E193.
  mla: Wang, Wen, et al. “Distinct Cerebellar Engrams in Short-Term and Long-Term
    Motor Learning.” <i>PNAS</i>, vol. 111, no. 1, National Academy of Sciences, 2014,
    pp. E188–93, doi:<a href="https://doi.org/10.1073/pnas.1315541111">10.1073/pnas.1315541111</a>.
  short: W. Wang, K. Nakadate, M. Masugi Tokita, F. Shutoh, W. Aziz, E. Tarusawa,
    A. Lörincz, E. Molnár, S. Kesaf, Y. Li, Y. Fukazawa, S. Nagao, R. Shigemoto, PNAS
    111 (2014) E188–E193.
date_created: 2018-12-11T11:54:43Z
date_published: 2014-01-07T00:00:00Z
date_updated: 2021-01-12T06:54:05Z
day: '07'
department:
- _id: RySh
doi: 10.1073/pnas.1315541111
intvolume: '       111'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3890858/
month: '01'
oa: 1
oa_version: Submitted Version
page: E188 - E193
publication: PNAS
publication_status: published
publisher: National Academy of Sciences
publist_id: '5174'
scopus_import: 1
status: public
title: Distinct cerebellar engrams in short-term and long-term motor learning
type: journal_article
user_id: 4435EBFC-F248-11E8-B48F-1D18A9856A87
volume: 111
year: '2014'
...
