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Being critical of criticality in the brain.

Beggs JM, Timme N - Front Physiol (2012)

Bottom Line: The hypothesis that the electrical activity of neural networks in the brain is critical is potentially important, as many simulations suggest that information processing functions would be optimized at the critical point.This hypothesis, however, is still controversial.Points and counter points are presented in dialog form.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Indiana University Bloomington, IN, USA.

ABSTRACT
Relatively recent work has reported that networks of neurons can produce avalanches of activity whose sizes follow a power law distribution. This suggests that these networks may be operating near a critical point, poised between a phase where activity rapidly dies out and a phase where activity is amplified over time. The hypothesis that the electrical activity of neural networks in the brain is critical is potentially important, as many simulations suggest that information processing functions would be optimized at the critical point. This hypothesis, however, is still controversial. Here we will explain the concept of criticality and review the substantial objections to the criticality hypothesis raised by skeptics. Points and counter points are presented in dialog form.

No MeSH data available.


Related in: MedlinePlus

A simple diagram of spins in the Ising model. (Left) At low temperature, nearest neighbor interactions dominate over thermal fluctuations. As a result, almost all the spins align in the same direction, producing a very ordered state. (Right) At high temperature, thermal fluctuations dominate over nearest neighbor interactions. As a result, the spins point in different directions, producing a very disordered state. (Center) At some critical temperature, nearest neighbor interactions and thermal fluctuations balance to produce a complex state.
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Figure 1: A simple diagram of spins in the Ising model. (Left) At low temperature, nearest neighbor interactions dominate over thermal fluctuations. As a result, almost all the spins align in the same direction, producing a very ordered state. (Right) At high temperature, thermal fluctuations dominate over nearest neighbor interactions. As a result, the spins point in different directions, producing a very disordered state. (Center) At some critical temperature, nearest neighbor interactions and thermal fluctuations balance to produce a complex state.

Mentions: Critio: Sure, let’s use a well explored model in this field: the Ising model (Brush, 1967; Cipra, 1987). [Critio grabs a napkin and sketches the left panel of Figure 1.]


Being critical of criticality in the brain.

Beggs JM, Timme N - Front Physiol (2012)

A simple diagram of spins in the Ising model. (Left) At low temperature, nearest neighbor interactions dominate over thermal fluctuations. As a result, almost all the spins align in the same direction, producing a very ordered state. (Right) At high temperature, thermal fluctuations dominate over nearest neighbor interactions. As a result, the spins point in different directions, producing a very disordered state. (Center) At some critical temperature, nearest neighbor interactions and thermal fluctuations balance to produce a complex state.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3369250&req=5

Figure 1: A simple diagram of spins in the Ising model. (Left) At low temperature, nearest neighbor interactions dominate over thermal fluctuations. As a result, almost all the spins align in the same direction, producing a very ordered state. (Right) At high temperature, thermal fluctuations dominate over nearest neighbor interactions. As a result, the spins point in different directions, producing a very disordered state. (Center) At some critical temperature, nearest neighbor interactions and thermal fluctuations balance to produce a complex state.
Mentions: Critio: Sure, let’s use a well explored model in this field: the Ising model (Brush, 1967; Cipra, 1987). [Critio grabs a napkin and sketches the left panel of Figure 1.]

Bottom Line: The hypothesis that the electrical activity of neural networks in the brain is critical is potentially important, as many simulations suggest that information processing functions would be optimized at the critical point.This hypothesis, however, is still controversial.Points and counter points are presented in dialog form.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Indiana University Bloomington, IN, USA.

ABSTRACT
Relatively recent work has reported that networks of neurons can produce avalanches of activity whose sizes follow a power law distribution. This suggests that these networks may be operating near a critical point, poised between a phase where activity rapidly dies out and a phase where activity is amplified over time. The hypothesis that the electrical activity of neural networks in the brain is critical is potentially important, as many simulations suggest that information processing functions would be optimized at the critical point. This hypothesis, however, is still controversial. Here we will explain the concept of criticality and review the substantial objections to the criticality hypothesis raised by skeptics. Points and counter points are presented in dialog form.

No MeSH data available.


Related in: MedlinePlus