UCLA
neuroscientists pinpoint new function for mirror neurons
Specialized
brain cells predict intentions as well as define actions
The road to interpreting intentions is paved
with mirror neurons. A study by UCLA neuroscientists featuring
functional magnetic resonance imaging and a well-stocked
tea service suggests for the first time that mirror neurons
help people understand the intentions of others -- a key
component to social interaction.
Reporting Feb. 22 in the online edition
of PLoS Biology, the UCLA team found that pre motor mirror
neuron areas of the brain -- areas active during the execution
and the observation of an action -- ascribe intentions
to actions when presented within a context. Previously,
these neurons were thought to be involved only in action
recognition.
In addition to expanding knowledge of how
the brain functions, the findings support a growing body
of evidence that imitation-based forms of treatments in
patients with autism and similar disorders may help stimulate
the function of these neurons, helping these patients
improve their ability to understand the intentions of
others and empathize with their thoughts and feelings.
"Understanding the intentions of others
while watching their action is a fundamental building
block of social behavior," said principal investigator
Dr. Marco Iacoboni, an associate professor in-residence
of psychiatry and biobehavioral sciences at the UCLA Neuropsychiatric
Institute’s Ahmanson Lovelace Brain Mapping Center
and the David Geffen School of Medicine at UCLA. "Our
findings show for the first time that intentions behind
actions of others can be recognized by the motor system
using a mirror mechanism in the brain. The same area of
the brain responsible for understanding behavior can predict
behavior as well."
Twenty-three research subjects underwent
functional MRI while alternately viewing three stimuli
presented in the form of short videos: 1) a hand grasping
a cup without context; 2) a tea service stocked with food
and drink before use and after use, or context only; and
3) the grasping of a tea cup within each of the two contexts,
signaling intent either to drink or to clean.
Actions embedded in context, compared with
the other two conditions, increased blood flow in the
posterior part of the brain’s inferior frontal gyrus,
known to be important for grasping control, and in the
adjacent sector of the ventral premotor cortex, where
hand actions are represented. Increased blood flow is
an indicator of increased neural activity.
Iacoboni also is affiliated with the UCLA
Brain Research Institute and the UCLA Center for Culture,
Brain and Development. Other members of the research team
included Istvan Molnar Szakacs and John C. Mazziotta of
UCLA, and Vittorio Gallese, Giovanni Buccino and Giacomo
Rizzolatti of the University of Parma, Italy.
Original source: http://www.innovations-report.com