Does the human brain teeter on the edge of chaos? Rat brains point to yes

A real human brain suspended in liquid within a human silhouette carved into acrylic, on display at the Bristol Science Centre in England. New research finds more evidence that the brain operates near a critical point.

Enlarge / A real human
brain suspended in liquid within a human silhouette carved into
acrylic, on display at the Bristol Science Centre in England. New
research finds more evidence that the brain operates near a
critical point. (credit: Ben Birchall/PA Images/Getty Images)

The human brain doesn’t seem like it would have much in common
with how water freezes into ice, or heats up into a gas. But over
the last decade, evidence has been mounting that the brain as a
system functions much like water approaching the critical point of
a phase transition. Now a team of Brazilian scientists has found
additional evidence in rat brains that this might indeed be the
case. The team described its findings in a
recent paper
in Physical Review Letters.

The notion of so-called “self-organized
criticality
” dates back to a landmark paper in
1987
, when the late Danish physicist Per Bak concluded that
nature’s exquisite order was the result of a kind of phase
transition. That precise moment of transition is colloquially known
as the “tipping point” or “critical point.”

A brain’s the thing

Typically, a classical phase transition only occurs when the
temperature and pressure are just right for a given system.
Self-organized criticality emerges spontaneously as the result of
many local interactions between the many elements of a system, like
millions of grains of sand running from the top to the bottom of an
hourglass. The pile grows, grain by grain, until it becomes
sufficiently unstable that the next grain to drop makes the pile
collapse in an avalanche. The base of the pile widens, restoring
stability, and the pile-up begins anew, until the sand pile hits
the critical point again. Those avalanches follow a so-called
power law,”
meaning smaller ones happen more often than larger ones.

Read 10
remaining paragraphs

Source: FS – All – Science – News
Does the human brain teeter on the edge of chaos? Rat brains point to yes