PMID- 23653596
OWN - NLM
STAT- MEDLINE
DCOM- 20140519
LR  - 20211021
IS  - 1662-5110 (Print)
IS  - 1662-5110 (Electronic)
IS  - 1662-5110 (Linking)
VI  - 7
DP  - 2013
TI  - Neural dynamics and information representation in microcircuits of motor cortex.
PG  - 85
LID - 10.3389/fncir.2013.00085 [doi]
LID - 85
AB  - The brain has to analyze and respond to external events that can change rapidly 
      from time to time, suggesting that information processing by the brain may be 
      essentially dynamic rather than static. The dynamical features of neural 
      computation are of significant importance in motor cortex that governs the 
      process of movement generation and learning. In this paper, we discuss these 
      features based primarily on our recent findings on neural dynamics and 
      information coding in the microcircuit of rat motor cortex. In fact, cortical 
      neurons show a variety of dynamical behavior from rhythmic activity in various 
      frequency bands to highly irregular spike firing. Of particular interest are the 
      similarity and dissimilarity of the neuronal response properties in different 
      layers of motor cortex. By conducting electrophysiological recordings in slice 
      preparation, we report the phase response curves (PRCs) of neurons in different 
      cortical layers to demonstrate their layer-dependent synchronization properties. 
      We then study how motor cortex recruits task-related neurons in different layers 
      for voluntary arm movements by simultaneous juxtacellular and multiunit 
      recordings from behaving rats. The results suggest an interesting difference in 
      the spectrum of functional activity between the superficial and deep layers. 
      Furthermore, the task-related activities recorded from various layers exhibited 
      power law distributions of inter-spike intervals (ISIs), in contrast to a general 
      belief that ISIs obey Poisson or Gamma distributions in cortical neurons. We 
      present a theoretical argument that this power law of in vivo neurons may 
      represent the maximization of the entropy of firing rate with limited energy 
      consumption of spike generation. Though further studies are required to fully 
      clarify the functional implications of this coding principle, it may shed new 
      light on information representations by neurons and circuits in motor cortex.
FAU - Tsubo, Yasuhiro
AU  - Tsubo Y
AD  - Laboratory for Neural Circuit Theory, RIKEN Brain Science Institute Wako, 
      Saitama, Japan.
FAU - Isomura, Yoshikazu
AU  - Isomura Y
FAU - Fukai, Tomoki
AU  - Fukai T
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Review
DEP - 20130503
PL  - Switzerland
TA  - Front Neural Circuits
JT  - Frontiers in neural circuits
JID - 101477940
SB  - IM
MH  - Action Potentials/*physiology
MH  - Animals
MH  - Humans
MH  - Motor Cortex/cytology/*physiology
MH  - Movement/physiology
MH  - Nerve Net/cytology/*physiology
MH  - Neurons/*physiology
PMC - PMC3642500
OTO - NOTNLM
OT  - cortical layer
OT  - gamma oscillation
OT  - irregular firing
OT  - juxtacellular
OT  - local circuit
OT  - multiunit
OT  - neural code
OT  - synchronization
EDAT- 2013/05/09 06:00
MHDA- 2013/05/09 06:01
PMCR- 2013/01/01
CRDT- 2013/05/09 06:00
PHST- 2012/12/07 00:00 [received]
PHST- 2013/04/16 00:00 [accepted]
PHST- 2013/05/09 06:00 [entrez]
PHST- 2013/05/09 06:00 [pubmed]
PHST- 2013/05/09 06:01 [medline]
PHST- 2013/01/01 00:00 [pmc-release]
AID - 10.3389/fncir.2013.00085 [doi]
PST - epublish
SO  - Front Neural Circuits. 2013 May 3;7:85. doi: 10.3389/fncir.2013.00085. 
      eCollection 2013.