The NYT reports here on a forthcoming fMRI research study which purports to demonstrate certain changes in brain activity that occur when a person is anticipating a painful shock but is given a hand to hold. The NYT suggests that there is a calming effect that varies based, in part, on the closeness of the relationship between the subject and the available hand:
In the study, to appear in the journal Psychological Science this year, neuroscientists at the University of Wisconsin and the University of Virginia used newspaper advertisements to recruit 16 couples from the Madison, Wis., region. The couples were all rated as very happily married on an in-depth questionnaire asking about coping styles, intimacy and mutual interests.
Lying in the jaws of an M.R.I. scanning machine and knowing that they would periodically receive a mild electric shock to an ankle, the women were noticeably apprehensive. Brain images showed peaks of activation in regions involved in anticipating pain, heightening physical arousal and regulating negative emotions, among other systems.
But the moment that they felt their husbands' hands — the men reached into the imaging machine — each woman's activity level plunged in all the regions gearing up for the threat. A stranger's hand also provided some comfort, though less so.
"The effect of this simple gesture of social support is that the brain and body don't have to work as hard, they're less stressed in response to a threat," said Dr. James A. Coan, a psychologist at the University of Virginia and the study's lead author. His co-authors were Dr. Hillary Schaefer and Dr. Richard J. Davidson of the University of Wisconsin.
. . .
The most profoundly comforting hand-holding was between "supercouples," whose scores on the marriage questionnaire reflected a extremely close relationship, the study found. The brain region involved in anticipating pain was particularly sensitive to this marital quality, suggesting that a touch between close partners can blunt the sensation of physical pain, which is related to the level of anticipation.