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To know someone I gave my heart to
Just tore my heart apart.
A love that is endless
Why did this love have to start?
Feeling the love I have for you
Just rushes through my veins.
Why does love have to be so much pain?
- Amanda Perez
Psychology researchers today increasingly use fMRI (functional magnetic resonance imaging) as a laboratory strategy. Research participants are placed in a large scanner that takes pictures of their brain and indicates which parts of it are more versus less active as gauged by blood flow while the participants are performing one or another activity, including doing nothing at all. This strategy makes sense given the growing interest of psychologists in locating what people do in terms of the structure and function of their brains, but the strategy has its own challenges.
Brain imaging is terribly expensive, and fMRI studies often enroll a very small number of research participants, limiting the power of the research design. The results of fMRI studies are often starkly empirical - merely determining what correlates with what - and critics have charged that researchers may simply be reporting associations that reflect chance, a possibility increased by the use of small sample sizes (Vul, Harris, Winkielman, & Pashler, 2009) .
In my opinion, fMRI results - like those from any research strategy - are most useful when there is a theory to make sense of them, especially when the theory guides the research design and analyses. There are countless parameters of a brain image. Theory can tell an investigator which parameters deserve attention and emphasis in a given study. In the absence of guiding theory, what we see are after-the-fact explanations of research results that may be simply that: after-the-fact. In the case of many fMRI studies, we may have examples of what biologist Stephen Jay Gould decades ago dubbed a "just-so story."
But there are exceptions, and these deserve our attention. An example of a theory-guided fMRI study was recently reported by University of Michigan psychologist Ethan Kross and his colleagues (2011). Their research has received widespread publicity, deservedly so, and it has been written about by other Psychology Today bloggers*.
Kross and his colleagues recruited 40 research participants who had recently experienced a romantic breakup and took pictures of their brains in different conditions. By the way, the participants were the breakees rather than the breakers, and they reported feeling quite rejected. Participants asked to look at photos of their ex-partner showed brain activity in exactly the same regions of their brains that were active when they were experiencing physical pain produced by thermal stimulation - heat, in plainer English. "Love hurts" was the unavoidable headline under which popular accounts of this research appeared.
Popular accounts further went on to conclude that the pain following a romantic breakup is "real" which is a conclusion that deserves scrutiny. As virtually all of us know, the pain of a romantic breakup is real - in psychological terms - and fMRI research is not needed to show this. Furthermore, the pain of a romantic breakup of course has a basis in the activity of the brain and nervous system, just as all of our thoughts, feelings, and actions have a basis in the activity of the brain and nervous system. To believe otherwise is to endorse a strict mind-body dualism long ago rejected by psychologists. Again, fMRI research is not needed to show this.
But what is important about this research is that pain due to a breakup and pain due to physical stimuli look the same in terms of brain images and by implication brain activity.
That's really interesting, and an explicit hypothesis led to this finding, one with theoretical and perhaps practical implications.
Theoretically, if I may tell my own just-so story, perhaps in the course of human evolution, romantic breakups piggy-backed onto existing brain structures and functions to register social rejection as painful ... and to lead to the sorts of behaviors that pain from physical stimuli produces, like putting a distance between the self and the source of pain and then taking time to recover from the damage inflicted.
Practically, this research suggests ways to deal with the pain of social rejection. For starters, perhaps one should not "confront" the source of the pain - the breaker - at least not if one wants to feel less pain. We do not advise someone who has burned their hand on a stove to ‘confront" the stove. We do not tell someone who has burned their hand to "process" or "talk through" what happened. We tell them to turn off the stove and to be more careful in the future. Duh.
Relationship problems foreshadow substance use, and here people may be trying to deaden the accompanying pain (cf. Simon & Barrett, 2010). I surfed around this morning and found an Internet website devoted to the "best" drugs, legal and illegal, to use after a romantic breakup! Most of the suggested drugs had analgesic properties. All of this makes perfect sense, but there is a slippery slope between drug use and drug abuse that make this a dangerous long-term remedy, no matter how successful it may be in the short-term. Alas, my caution pertains to chocolate ice cream as well as to alcohol and the opiates.
So, how about physical exercise? Research is clear that vigorous aerobic exercise can reduce physical pain. I bet that it reduces the pain of social rejection as well, although relevant research is needed. Perhaps it has already been done and escaped my searches. Regardless, we have a clear hypothesis, and that is good if science is to contribute to a life lived well, or at least not painfully.
* See http://www.psychologytoday.com/blog/choke/201104/being-rejected-hurts-literally and
http://www.psychologytoday.com/blog/brain-sense/201103/lost-love-hurtsliterally.
References
Kross, E., Berman, M., Mischel, W., Smith, E.E., & Wager, T. (2011). Social rejection shares somatosensory representations with physical pain. Proceedings of the National Academy of Sciences.
Simon, R. W., & Barrett, A. E. (2010). Nonmarital romantic relationships and mental health in early adulthood: Does the relationship differ for women and men? Journal of Health and Social Behavior, 51, 168-182.
Vul, E, Harris, C, Winkielman, P & Pashler, H (2009) "Puzzlingly high correlations in fMRI studies of emotion, personality, and social cognition. Perspectives on Psychological Science, 4, 274-290.
