PMID- 15390164
OWN - NLM
STAT- MEDLINE
DCOM- 20050511
LR  - 20071115
IS  - 1050-9631 (Print)
IS  - 1050-9631 (Linking)
VI  - 15
IP  - 1
DP  - 2005
TI  - Spatiotemporal visualization of long-term potentiation and depression in the 
      hippocampal CA1 area.
PG  - 68-78
AB  - Long-term potentiation (LTP) in the CA1 area of the hippocampus depends 
      critically on the statistical characteristics of its stimulus. The ability of 
      optical imaging to record spatial distribution has made it possible to examine 
      systematically the effect of higher-order statistical characteristics, such as 
      the correlation between successive pairs of inter-stimulus intervals (ISIs) on 
      the induction of LTP. Therefore, the function of frequency (first-order) and 
      temporal pattern (second-order) was examined using this imaging technique. To 
      investigate the dependence of LTP on frequency, periodic stimuli with the same 
      number of pulses were applied at different frequencies (1-10 Hz, n=200) to 
      Schaffer commissural-collateral fibers. While stimulus frequencies from 2-10 Hz 
      induced LTP of varying magnitudes and low-frequency stimuli (1 Hz) induced 
      long-term depression (LTD), spatial distribution remained consistent. These 
      results suggest that induction frequency has a greater effect on the magnitude of 
      LTP than on its spatial distribution. By employing nonperiodic stimuli at the 
      same mean frequency (2 Hz), the effect of varying the temporal structure of a 
      stimulus was also investigated. As the correlation of successive ISIs was 
      increased from negative to positive, not only did the magnitude of LTP increase, 
      there was also a statistically significant change in the spatial distribution of 
      LTP. Interestingly, when a strong negatively correlated stimulus was applied, 
      both LTP and LTD were simultaneously observed in the CA1 area. It was also found 
      that the magnitude of LTP 200-300 mum distal to the cellular layer was larger 
      than that of the LTP induced proximal (<100 microm) to that layer. These results 
      support the hypothesis that the spatial distribution of LTP throughout the 
      hippocampus relies principally on the temporal patterning of input stimulation. 
      This insight into the structure of the CA1 neural network may reveal the 
      importance of stimulus timing events in the spatial encoding of memories.
CI  - Copyright (c) 2004 Wiley-Liss, Inc.
FAU - Aihara, Takeshi
AU  - Aihara T
AD  - Department of Information-Communication Engineering, Tamagawa University, Tokyo, 
      Japan. aihara@eng.tamagawa.ac.jp
FAU - Kobayashi, Yuki
AU  - Kobayashi Y
FAU - Tsukada, Minoru
AU  - Tsukada M
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Hippocampus
JT  - Hippocampus
JID - 9108167
SB  - IM
MH  - Action Potentials/*physiology
MH  - Animals
MH  - Electric Stimulation
MH  - Guinea Pigs
MH  - Hippocampus/anatomy & histology/*physiology
MH  - Long-Term Potentiation/*physiology
MH  - Long-Term Synaptic Depression/*physiology
MH  - Memory/physiology
MH  - Models, Neurological
MH  - Nerve Net/anatomy & histology/physiology
MH  - Neural Pathways/anatomy & histology/*physiology
MH  - Neurons/*physiology
MH  - Organ Culture Techniques
MH  - Reaction Time/physiology
MH  - Synaptic Transmission/physiology
MH  - Time Factors
EDAT- 2004/09/25 05:00
MHDA- 2005/05/12 09:00
CRDT- 2004/09/25 05:00
PHST- 2004/09/25 05:00 [pubmed]
PHST- 2005/05/12 09:00 [medline]
PHST- 2004/09/25 05:00 [entrez]
AID - 10.1002/hipo.20031 [doi]
PST - ppublish
SO  - Hippocampus. 2005;15(1):68-78. doi: 10.1002/hipo.20031.