A recent study using mice to mimic stress and depression in adolescents suggests that the teenage years are a particularly vulnerable time for the brain.  Working with mice who carried an introduced human gene mutation for depression, the researchers exposed some of the adolescent mice to social stress (isolation for three weeks) and kept a control group of mice stress-free.  There were two important findings.  First, the gene mutation for depression had no effect on mouse behavior except among the stressed mice.  Second, they found that the behavior change may be mediated by increases in cortisol (a stress hormone) and decreases in dopamine (a neurotransmitter in the brain).  Morever, after they returned the stressed mice to their preferred social environment, the behavioral abnormalities remained.  This study, and others like it, suggest that once activated during adolescence, the neuro-biological pathway active in depression does not turn off, even after the stressor has passed.

The take-home message?  We have another reason to increase our efforts at promoting healthy family environments for our children, and another reason that insurance companies should stop refusing to pay for marriage counseling.  A loving and secure attachment between married partners is the foundation for well-adjusted and resilient children.  …and possibly a buffer against a life suffering with depression.

Check out a more detailed summary of the study: http://www.hopkinsmedicine.org/news/publications/psychiatry_newsletter/hopkins_brainwise_spring_2013/stress_can_it_bring_more_than_teen_angst

or the study itself: http://www.sciencemag.org/content/339/6117/335.long

It is scary to be diagnosed with depression.  However, it’s a lot less scary to be diagnosed with depression when you know that your grandmother and your uncle on your mother’s side also had it.  We may live in the age of biological psychiatry, and the NIH may have just announced their plan to map the human brain http://www.neuroscienceblueprint.nih.gov/connectome/, but we are still haunted by a view of brain illnesses that led our forefathers to drill holes in the skulls of depressed persons to let out the evil spirits.  Stigma is alive and well.  But its impact is reduced by the realization that, “It’s not my fault.”  Moreover, people diagnosed with the illness may be more open to the proven treatments (talk therapy combined with medication) when shown evidence that the predisposition is inherited, not a function of personal failure.   Most of my new patients with the illness have no idea that they are suffering from depression; they just know that they are suffering — sometimes for 30 years.  Without treatment.  Blaming themselves.  Concluding that they are worthless and that their situation is hopeless.

If depression runs in your family, do your children a favor.  Save them potentially years of suffering.  Tell them about it.

Archeological evidence of our human ancestors, observations of eating behavior in modern hunter-gatherer tribes, the anatomy of our digestive system and current neuro-scientific research suggest that humans may have a hard-wired preference for high-fat and high-calorie foods.  The available data lead scientists to estimate that ancient humans consumed more than half of their calories as meat, preferably large game.  Before the development of agriculture, some 10,000 years ago, ancient hunter-gatherer tribes of 25 or so members moved to different geographic locations to follow their food sources.  As one area became depleted of food, they moved to a new area.  This, as well as seasonal variation in the availability of food, must have resulted in periods of food plenty and scarcity.  It was in this unstable food environment that our “survival of the fittest” eating behaviors evolved.  One theory suggests that there would have been greater survival advantage to humans who consumed as much animal fat and carbohydrates as possible whenever possible, regardless of how hungry they may have been at the moment.  Those who had fattened up in periods of plenty would have been more likely to survive the periods of scarcity.

Combined with research showing that animals eat larger quantities and gain more weight when highly palatable food is easily available, our evolution-imposed food preferences may contribute to the current obesity epidemic:  we have easy access to tasty high-fat and high-calorie foods in combination with hard-wired preferences to consume these foods with abandon whenever they are available.  In addition, neuro-imaging studies show that, in some people, the brain reward areas are more highly activated when they are presented with high-calorie foods, perhaps suggesting one mechanism underlying differences among people in the ability to “resist” high-calorie foods.

To read more about this topic, check out this article:  The Modern Obesity Epidemic, Ancestral Hunter-Gatherers and the Sensory/Reward Control of Food

 

Check out this article entitled, “Social rejection shares somatosensory representations with physical pain” by Kross et al.  For non-geeks, here’s my summary:  Researchers studied the brains of 40 adults (21 women, 19 men) who had been rejected by a romantic partner within the previous six months.  Using functional MRI imaging, they compared the location of brain activity that occurred while the research participants experienced physical pain (heat applied to the forearm just below their pain tolerance) and while they experienced emotional pain (seeing a picture of the rejecting partner and remembering how it felt to be rejected).  The same brain regions were activated with both types of pain, and the authors concluded that “…intense social rejection may represent a distinct emotional experience that is uniquely associated with physical pain” (p. 4).  In essence, “hurting” after an unwanted breakup is not simply a metaphor.

Rejection and Pain  Link to article: http://www.pnas.org/content/early/2011/03/22/1102693108.full.pdf

http://www.elainebaileyinternational.com/wordpress/wp-content/uploads/2012/08/Triune-Brain.png

The Triune Brain

Blame it on your 3-part brain, each part the product of a different phase in evolutionary time.  Emotions live in the limbic brain; thoughts live in the neocortex.  Emotional information gets lost in translation.   

 

(Figure adapated from http://elainebaileyinternational.com/wordpress/?s=triune+brain&.x=0&.y=0)

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