PMID- 12417232
OWN - NLM
STAT- MEDLINE
DCOM- 20021223
LR  - 20190922
IS  - 1388-2457 (Print)
IS  - 1388-2457 (Linking)
VI  - 113
IP  - 11
DP  - 2002 Nov
TI  - The profile of the recovery cycle in human primary and secondary somatosensory 
      cortex: a magnetoencephalography study.
PG  - 1787-93
AB  - OBJECTIVE: To estimate the lifetime of sensory memory in human primary (SI) and 
      secondary (SII) somatosensory cortex with a view to furthering our understanding 
      of the roles played by these cortices in the processing of tactile information. 
      METHODS: Somatosensory evoked fields (SEFs) were recorded following trains of 5 
      electrical pulses applied to the right median nerve at the wrist using a 
      whole-head 80 channel magnetoencephalography (MEG) system. Recordings were 
      acquired for trains of pulses with differing interstimulus intervals (ISIs) 
      occurring at 100, 200, 300, 400 and 500 ms. The profile of SEF intensities for 
      the different ISIs provided an estimate of the recovery cycle of evoked neuronal 
      activity, and the time constant of the exponential curve fitted to the recovery 
      cycle was calculated to obtain a putative measure of the lifetime of somatic 
      sensory memory in SI and SII. RESULTS: The estimated time constants were 
      0.11+/-0.06 s (mean+/-SD) in SI and 0.82+/-0.34 s in SII. The mean time constant 
      in SII was significantly longer than that in SI (Student's paired t test: 
      P=0.021; analysis of variance: F(1,3)=19.7, P=0.021). CONCLUSIONS: These data 
      indicate that the lifetime of somatic sensory memory is of longer duration in 
      higher order cortical areas than in primary sensory cortex in the somatosensory 
      information processing system.
FAU - Hamada, Yasukazu
AU  - Hamada Y
AD  - Department of Linguistics and Philosophy, Massachusetts Institute of Technology, 
      Cambridge, MA, USA. hamada@neptune.kanazawa-it.ac.jp
FAU - Otsuka, So
AU  - Otsuka S
FAU - Okamoto, Takashi
AU  - Okamoto T
FAU - Suzuki, Ryoji
AU  - Suzuki R
LA  - eng
PT  - Clinical Trial
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Netherlands
TA  - Clin Neurophysiol
JT  - Clinical neurophysiology : official journal of the International Federation of 
      Clinical Neurophysiology
JID - 100883319
SB  - IM
MH  - Adult
MH  - Electric Stimulation
MH  - Electromagnetic Fields
MH  - Evoked Potentials, Somatosensory/physiology
MH  - Humans
MH  - *Magnetoencephalography
MH  - Male
MH  - Median Nerve/physiology
MH  - Neurons/physiology
MH  - Somatosensory Cortex/*physiology
MH  - Touch/physiology
EDAT- 2002/11/06 04:00
MHDA- 2002/12/27 04:00
CRDT- 2002/11/06 04:00
PHST- 2002/11/06 04:00 [pubmed]
PHST- 2002/12/27 04:00 [medline]
PHST- 2002/11/06 04:00 [entrez]
AID - S1388245702002584 [pii]
AID - 10.1016/s1388-2457(02)00258-4 [doi]
PST - ppublish
SO  - Clin Neurophysiol. 2002 Nov;113(11):1787-93. doi: 10.1016/s1388-2457(02)00258-4.