Pages

24 July 2012

The Insular Brain of a Champion

Hidden behind the temporal lobe, lies a portion of the cerebral cortex known as the insular cortex, or the insula. The insula serves several functions, but one of the more recently discovered roles of this island of gray matter is to anticipate the future of the person's "body sense." Brains which can do this more quickly and efficiently are able to perform skilled motor functions -- such as Olympic sports -- more skillfully.
Insular Cortex

Recent studies indicate that the brain's insular cortex may help a sprinter drive his body forward just a little more efficiently than his competitors. This region may prepare a boxer to better fend off a punch his opponent is beginning to throw as well as assist a diver as she calculates her spinning body's position so she hits the water with barely a splash. The insula, as it is commonly called, may help a marksman retain a sharp focus on the bull's-eye as his finger pulls back on the trigger and help a basketball player at the free-throw line block out the distracting screams and arm-waving of fans seated behind the backboard.

The insula does all this by anticipating an athlete's future feelings, according to a new theory. Researchers at the OptiBrain Center, a consortium based at the University of California, San Diego, and the Naval Health Research Center, suggest that an athlete possesses a hyper-attuned insula that can generate strikingly accurate predictions of how the body will feel in the next moment. That model of the body's future condition instructs other brain areas to initiate actions that are more tailored to coming demands than those of also-rans and couch potatoes.

This heightened awareness could allow Olympians to activate their muscles more resourcefully to swim faster, run farther and leap higher than mere mortals. In experiments published in 2012, brain scans of elite athletes appeared to differ most dramatically from ordinary subjects in the functioning of their insulas. Emerging evidence now also suggests that this brain area can be trained using a meditation technique called mindfulness—good news for Olympians and weekend warriors alike.

... The motor cortex and memory systems, for example, encode years of practice. Nerve fibers become ensconced in extra layers of a protective sheath that speeds up communication between neurons, producing lightning-fast reflexes. Understanding the brain at its athletic best is the goal of psychiatrist Martin Paulus and his colleagues at the OptiBrain Center. They propose that the insula may serve as the critical hub that merges high-level cognition with a measure of the body's state, to insure proper functioning of the muscles and bones that throw javelins and land twirling dismounts from the high bar. "The key idea we're after is how somebody responds when they get a cue that predicts something bad will happen," Paulus says. "The folks that are performing more optimally are the ones who are able to use that anticipatory cue to adjust themselves and return to equilibrium."

...The insula generates this sense by maintaining a map of all your far-flung organs and tissues. Certain neurons in the insula respond to rumblings in the intestines, for example, whereas others fire to reflect a toothache. To manage the influx of messages bombarding it from throughout the body, the insula collaborates closely with the anterior cingulate cortex, an area crucial for decision-making, to evaluate and prioritize those stimuli. This raw representation of bodily signals has been hypothesized for more than a century to be the origin of emotions.

...Taken together, the studies indicate that men and women who have extreme physical abilities show greater insula activation when anticipating a change to their internal feelings, whether emotional or physical.

...the insula does not live in the present, but the future. "We're responding to information incorporated from physiology, cognition, our surroundings," Simmons says. "By the time we've integrated all that, it's part of the past." The ability to forecast can also backfire, producing disorders such as anorexia nervosa, which combines lapses in bodily awareness with a concern for how food consumption now will alter body image in the future. "It's the anticipation that's getting in your way," Simmons says. Indeed, brain scans of individuals with eating disorders and post-traumatic stress disorder show that insula activity diverges from that seen in healthy subjects, suggesting impairments in this area.

Train your interoception

For aspiring athletes or individuals who suffer insular dysfunction, there are reasons to hope interoception is trainable. A meditation technique called mindfulness encourages people to tune into their present thoughts, emotions and bodily sensations. _SciAm

Of course the insula does not merely serve in anticipation of moment-to-moment changes in body sense accompanying motor activity. Insular activity is incorporated in virtually all conscious and subconscious mental activity. In fact, without this "body sense," the human mind would go likely go insane, with nothing to ground and integrate the external senses.

This is, in fact, one of the challenges for achieving human level artificial intelligence -- although most researchers in the field have not discovered it yet.

It is true that the insula is not the only part of the brain involved in body mapping or anticipation of body configuration after an imagined movement. But the insula -- due to its particular connections, functions at a higher level of automatic control, which may mean that it is particularly well trained at elite levels of brain-body coordination. As skills training progresses, the insula likely changes in size, connectivity, and its cytoarchitecture is most probably modified.

Current tools for studying changes in small modular areas of the brain which occur with training, are still relatively primitive and cumbersome. But they will get better.

No comments:

Post a Comment

“During times of universal deceit, telling the truth becomes a revolutionary act” _George Orwell