brain presumably goes back to normal.
But with each use after, the drug’s
effect will be a little less because your
brain circuits have adjusted to it. “You
habituate,” says Koob.
That habituation is a strong form
of tolerance. It is also a form of
degenerative plasticity, because brain
cells and neural pathways can die off.
Recovery from addiction (be it
from a substance or a behaviour such
as gambling, shopping, food or sex)
depends on regenerative brain plasticity.
This process is not simply a matter of
growing new brain cells: when a brain
cell is dead, it’s gone forever. But the
brain can be dazzling in its ability to
rewire and compensate.
“What you do is recruit other systems
to give you a boost,” Koob says.
While the brain can be rewired
following addiction—or other injuries and
experiences—the process can take years
and involve intensive and costly therapy.
“What we’ve learned in neuroscience
in the past 40 or 50 years is that the
brain has that capability to be plastic,
the capability to be changing,” Koob
says. “It’s really a profound statement
because it means addiction is a brain
disorder and recovery is a brain
Your brain is plastic. Not the plastic
your computer keyboard is made of or
the plastic used for knives and forks at
Plastic as in the Greek word plastikos,
meaning to mould or to form. Brain
plasticity means your brain has the
ability to change. Brain plasticity is
linked to a number of brain functions:
memory, addiction and recovery of
function, such as after a stroke or injury.
When we learn to do something
involving our motor skills—for example,
play a piano or drive a car—our brain
plasticity changes the structure of cells
in our nervous system. If for some
reason the changes can’t take place, the
motor learning can’t take place either.
For the most part, our brains are the
most plastic in the early years, the first
six years of life. This is when the greatest
part of brain architecture is being
built. Billions of brain circuits (neural
pathways) are forming and behaviours
are starting to emerge. Both are shaped
by a combination of environment and
During this time of intense
development, the brain is fragile. It
can be easily harmed, but can also
heal easily. Here again, how our brain
responds is the result of a combination
Your brain is plastic
And it has the ability to change
WRITTEN BY TERRY BULLICK
of environment and genetics, also
known as epigenetics.
While our brains are most plastic in
childhood, they have some plasticity
throughout life. This ability for the brain
to change is crucial to being able to
adapt and change as we age.
In a paper published in 2003 by the
American Psychological Society (now
called the Association for Psychological
Science), Bryan Kolb and Robbin Gibb
of the Canadian Centre for Behavioural
Neuroscience at the University of
Lethbridge, along with Terry E.
Robinson of the University of Michigan,
wrote: “Recent research has shown
that brain plasticity and behaviour can
be influenced by a myriad of factors,
including pre- and postnatal experience,
drugs, hormones, maturation, aging,
diet, disease and stress.
“Understanding how these factors
influence brain organization and
function is important not only for
understanding both normal and
abnormal behaviour, but also for
designing treatments for behavioural
and psychological disorders ranging
from addiction and stroke.”
George Koob, director of the U.S.
National Institute on Alcohol Abuse and
Alcoholism at the National Institutes of
Health, has spent his career looking at
how drugs affect brain plasticity.
“Drugs change the brain, whether
it’s with one glass of wine at dinner or
smoking a pipe of crack cocaine, and the
change begins with the first use of the
drug,” says Koob.
As the effects of the drug wear off, the
The ability for the brain to
change is crucial to being
able to adapt and change
as we age
It means addiction is
a brain disorder and
recovery is a brain