Thursday, December 30, 2010
Amygdala Centre for Social Network
I suspect that this is something very important. Skip the rest of the brain. This is the switch box for emotional coding, or at this point we can presume that is true. Why this is important is that it is my opinion at least that our entire decision making is done through emotional loading. This is the principle reason it is so difficult to undo a bad conception in the real world even in the face of mounting evidence. Objectivity and balance only comes after the emotional outburst on confronting the changing facts on the ground.
I am sure that the above conjecture may well be violently opposed by those who have bought into another specialist dogma. As an aside, in my manuscript titled ‘Paradigms Shift’ I introduce a whole range of new conceptions. What I found intriguing is that my sample audience all had the same reaction. They agreed and enjoyed all of the material until they hit a specific topic that they thought themselves well versed on. At that point the rejection was palpable. It was different for every reader.
Everyone has a large emotional loading attached to material they trained on and studied. Rejecting that, however dated is difficult and few are truly ready for it.
For now we discover that this switch box tracks our social network in particular, but also strongly suggests that my argument that the natural village size is properly around 150. I would like to revisit that idea. The data suggests that key individuals develop the social networking capacity that in fact links the rest in terms of their own capacity.
This means that we need to design of virtual community in terms of a range of sub social networks to fully understand it. Obvious when one thinks it through, but only after one sees the data.
A larger emotion-processing brain centre is linked to a bigger circle of friends.
The size of your amygdala (circled) indicates the extent of your social network. Brad Dickerson
How many friends do you have? A rough answer can be predicted by the size of a small, almond-shaped brain structure that is present in a wide range of vertebrates, scientists report today in Nature Neuroscience.
The researchers studied the amygdala, which is involved in inter-personal functions such as interpreting emotional facial expressions, reacting to visual threats and trusting strangers. Inter-species comparisons in non-human primates have previously shown that amygdala volume is associated with troop size, suggesting that the brain region supports skills necessary for a complex social life1.
On the basis of these past findings, psychologist Lisa Feldman Barrett of
in , wondered whether a larger
amygdala size allows some humans to build a richer social world. Boston, Massachusetts
Barrett's team measured the amygdala volume in 58 healthy adults using brain images gathered during magnetic resonance imaging sessions. To construct social networks, the researchers asked the volunteers how many people they kept in regular contact with, and how many groups those individuals belonged to.
They found that participants who had bigger and more complex social networks had larger amygdala volumes. This effect did not depend on the age of the volunteers or their own perceived social support or life satisfaction, suggesting that happiness is not the underlying causal factor that links the size of this brain structure in an individual to their number of friends2.
"We'd all predict this relationship should be found, but [the authors] did it in a very smart way by ruling out other variables," says cognitive neuroscientist Kevin Ochsner of
University in . "That's why I think this
paper is going to end up being a citation classic, because it demonstrates the
relationship in a way that gives you confidence that it's real," he adds. New York City
But it's still a mystery how the amygdala contributes to social networks. Perhaps the structure's response to faces, emotions or emotional memories influences whether someone decides to develop and maintain relationships, says Brad Dickerson, a cognitive neuroscientist at Massachusetts General Hospital in Boston, who helped lead the study.
It's likely that social behaviour relies on a much broader set of brain regions, Dickerson says. In the future, the team will use functional neuroimaging approaches to determine the relationship between patterns of brain activity in an individual and the size of social groups to which they belong.
Another important question is whether a big amygdala is a cause or a consequence of having a large social network. "In the end, it's probably some of both," Ochsner says. "But you first had to establish that the relationship really exists before you could address those critical questions."