Only the lonely.....

I read today about a study of the chemical changes in the brains of prairie voles on separation from their mates.  Apparently they became lethargic and unmotivated, and the emotional centers of their brains were riddled with CRF (corticotropin releasing factor), similarly to human suicide victims' brains.   A little googling tells me that CRF is important to metabolism, thermogenesis, circadian rhythms and stress response.    An antibody that blocks reception of that chemical is being tested for treatment of general anxiety disorder, gastric ulcers and alcoholism.  

No one is suggesting that because lonely prairie voles don't flail when dangled by their tails they are depressed.  It is hard to determine if a prairie vole is caught up in a cycle of self-defeating thoughts that make the contemplation of suicide seem like an acceptable alternative to the fatigue of making it through colorless days into sleepless nights.  When they float when dropped into a tank of water, instead of swimming madly to the edge, one doesn't immediately assume they have decided to end it all.  It seems to me simply that they have lost the impulse to do anything for themselves.

At first look, this appears as a kind of altruism on the cellular level.  A mate gives a reason to do whatever it is one does.  In evolutionary terms, they offer a potential future in following generations, and we behave as we do to attract and sustain productive relationships.  As mammals, we depend on limbic resonance with others to regulate our metabolism, immune response, sleep rhythms, hormonal levels, heart and breathing rates, and other physiological events.  What is interesting in this study is that the voles separated from their siblings were not affected the way those removed from their mates were.  It wasn't just the lack of limbic regulation that made the voles unresponsive.  It was the loss of the quality and intensity of interaction that only a mate provides.  Or a prairie vole's mate, at least.

Prairie voles, like humans, pair bond and raise their offspring together.  Most rodents don't, and it's hard to imagine a mouse hanging limp by its tail just because it was removed from another mouse for a few days.  Nor are prairie voles any more sexually monogamous than other rodents, given the right opportunities.  They don't mope because they aren't getting any.  How useless is that?  Better to wiggle harder to get away and find another likely piece of vole ass.  No, prairie voles have opiate receptors that fire madly in the presence of their particular mate, the one they bonded with during their first mating session.  BECAUSE THAT SEX SESSION LASTED 24 HOURS!!!   How's that for a honeymoon?

In neurochemical terms, though, bereavement is a drug withdrawal response.  Pair-bonding animals, humans included, have a ridiculous concentration of oxytocin receptors in their nucleus accumbens (aka pleasure center), an important little nub in the brain right next to the olfactory tubercle.  A whiff of romance is what it takes to remember that one special mate and go wild.  No one else quite measures up for the poor little vole.  Nor do the regular activities of eating, sleeping, and swimming to safety.

This study didn't address how long the effect lasted.  Nor does it say how long they left the waterlogged voles in the tank.  Did they wait for them to sink?  Did the voles eventually drift to the shallow end?  Or, after 20 minutes or so, did the voles decide to pull their soggy butts out?  Is this the forerunner to hydrotherapy for the bereaved?  Now we get close to something truly important to me, besides being immersed in water.  I am curious about inspiration, those sparks of arousal that motivate activity and creativity.  What is the chemical signature of beauty?  What will bring a vole, or a human, back to life from a period of depression?  On a smaller, personal scale, what brings a day to life after a night of forgetfulness (or worse)?

Today it is prairie voles.