A Decade after The Decade of the Brain
Fundación de Neurociencias
About Nora D. Volkow
February 18, 2010
In 1990, Congress designated the 1990s the “Decade of the Brain.”
President George H. W. Bush proclaimed, “A new era of discovery is
dawning in brain research.” During the ensuing decade, scientists
greatly advanced our understanding of the brain.
The editors of Cerebrum asked the directors of seven brain-related
institutes at the National Institutes of Health (NIH) to identify the
biggest advances, greatest disappointments, and missed opportunities
of brain research in the past decade—the decade after the “Decade of
the Brain.” We also asked them what looks most promising for the
coming decade, the 2010s. Our experts focused on research that might
change how doctors diagnose and treat human brain disorders.
We hear from Nora D. Volkow, director of the National Institute on
Drug Abuse; Thomas R. Insel, director of the National Institute of
Mental Health; Story Landis, director of the National Institute of
Neurological Disorders and Stroke; Kenneth R. Warren, acting director
of the National Institute on Alcohol Abuse and Alcoholism; Paul A.
Sieving, director of the National Eye Institute; James F. Battey,
director of the National Institute on Deafness and Other Communication
Disorders; and Richard J. Hodes, director of the National Institute on
Aging.
Neuroscience is at a historic turning point. Today, a full decade
after the “Decade of the Brain,” a continuous stream of advances is
shattering long-held notions about how the human brain works and what
happens when it doesn’t. These advances are also reshaping the
landscapes of other fields, from psychology to economics, education
and the law.
Until the Decade of the Brain, scientists believed that, once
development was over, the adult brain underwent very few changes. This
perception contributed to polarizing perspectives on whether genetics
or environment determines a person’s temperament and personality,
aptitudes, and vulnerability to mental disorders. But during the past
two decades, neuroscientists have steadily built the case that the
human brain, even when fully mature, is far more plastic—changing and
malleable—than we originally thought.1 It turns out that the brain (at
all ages) is highly responsive to environmental stimuli and that
connections between neurons are dynamic and can rapidly change within
minutes of stimulation.
Neuroplasticity is modulated in part by genetic factors and in part by
dynamic, epigenetic changes that influence the expression of genes
without changing the DNA sequence. Epigenetic processes are of
particular clinical interest because their external triggers (such as
early parental care, diet, drug abuse and stress) can affect a
person’s vulnerability to many diseases, including psychiatric
disorders. In addition, in contrast to genetic sequence differences,
epigenetic alterations are potentially reversible, and thus amenable
to public health policy interventions.
It also has become increasingly clear that the human brain is
particularly sensitive to social stimuli, which likely has accelerated
the rate of human brain evolution. Humans have evolved a complex
neuronal circuitry in large areas in the brain to process complex
social information (such as predicting others’ reactions and emotions)
and to respond appropriately. New research has revealed that social
stimuli (such as parenting style and early-life stress) can
epigenetically modify the expression of genes that influence brain
morphology and function including the sensitivity of an individual to
stressful stimuli.2 In the future, this knowledge will enable us to
tailor personalized prevention interventions that are based on
information on how genetics and epigenetics affect brain function and
behavior. For example, a recent study showed that a prevention
intervention based on improving parenting style reduced the risk for
substance use disorders only in adolescents with a particular variant
of a gene that recycles the chemical serotonin back into the neurons,
which is a variant that results in greater sensitivity to social
adversity.3
In the coming decade, insights about what underlies neuroplasticity,
combined with technological advances that allow us to “see” with
greater precision the human brain in action, are bound to
revolutionize the way we view learning and the methods we use to
educate young people. New research will also show us how to help
people overcome or compensate for many of the deficits associated with
drug abuse, addiction and other mental disorders.4
For example, scientists are using imaging technologies in
neurofeedback programs that train people to voluntarily recalibrate
their neural activity in specific areas of the brain, allowing them to
gain unprecedented control over, for example, pain perception5 or
emotional processing.6 During drug addiction treatment, this approach
could greatly reduce the risk of relapse by enabling a patient to
control the powerful cravings triggered by a host of cues (e.g.,
people, things, places) that have become tightly linked, in the brain
of the user, to the drug experience.
Other promising advances stem from ongoing research and development of
direct communication pathways between a brain and external computer
devices, the so called brain-computer interfaces (BCI). In a recent
study, one version of BCI appeared to help paralyzed stroke victims
regain some movement control.7 In the next decade, forms of BCI might
help people with a variety of neuropsychiatric conditions that have
proved resistant to traditional treatments. For example, early
evidence suggests that BCI training could benefit patients with
epilepsy or attention-deficit/hyperactivity disorder (ADHD) that is
unresponsive to drugs.8
As we build on these rapid advances in neuroscience research, we must
keep a watchful eye on their vast social and political implications.
For example, neurologists have started to uncover the molecular
components and neural circuitry that underlie the learning process.9
We also are learning how to use transcranial magnetic stimulation
(TMS), a noninvasive method to modulate the activity within a neural
circuit, more effectively.10 Should we use this knowledge to better
educate young people and teach new skills to seniors, or should we use
these tools only to treat people with neuropsychiatric disorders? As
we begin to understand how parenting styles affect the development and
function of the brain, how far should we go to protect children from
the long-term and deleterious effects of bad parenting?
Recent progress in brain research and associated fields has been
impressive, and we are sure to witness further acceleration in the
pace of neuroscientific discovery in the next couple of decades.
Indeed, we are entering a new era in which our technologies are
beginning to affect our lives in profound ways. We are bound to recast
our relationship with our brains and, in the process, to redraw the
boundaries of human evolution.
Comments
New research on Brain
Ramesh Raghuvanshi
2/22/2010 11:13:13 AM
Can anybody give a guarantee that scientists not misuse the new
research against their enemies? How much do people take advantage of
this new research? A child's brain starts to develop even in womb,
also how can we prevent bad parenting? Wishful thinking and practice
have vast differences; how can we will bridge this gap?
Post a Comment »
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