Our Complex Brains

So after a decade or more of modern neuroscience research using fMRI and other advanced imaging scans as well as extensive gene studies, what do we know about the brain?

It is a far more complex organ than we previously had imagined.

A great article in this week’s edition of Newsweek by the editor in chief of the Harvard Mental Health letter, Michael Craig Miller, describes the difficulty in understanding emotions in the brain:

Last year Drs. Peter J. Freed and J. John Mann, publishing in The American Journal of Psychiatry, reported on the literature of sadness and the brain. In 22 studies, brain scans were performed on nondepressed but sad volunteers. Sadness was mostly induced (subjects were shown sad pictures or films, asked to remember a sad event), although, in a couple of studies, subjects had recently experienced a loss.

In the aggregate, sadness appeared to cause altered activity in more than 70 different brain regions. The amygdala and hippocampus both show up on this list, as do the front part of the brain (prefrontal cortex) and the anterior cingulate cortex. A structure called the insula (which means “island”) also appears here — it is a small region of cortex beneath the temporal lobes that registers body perceptions and taste.

The authors believe this complicated picture makes sense. The brain regions on their list process conflict, pain, social isolation, memory, reward, attention, body sensations, decision making and emotional displays, all of which can contribute to feeling sad. Sadness triggers also vary — for example, the memory of a personal loss; a friend stressing over a work conflict; seeing a desolate film.

Seventy different brain regions! Which means our constant search for a single cause of a problem like depression or bipolar disorder is unlikely to find merit, even within brain research. The brain’s complexity is interwoven and interconnected in ways we couldn’t even begin to imagine 30 years ago. No single gene or set of genes or regions of the brain will likely ever be the only implicated for our mental health concerns.

Miller also notes, as we have long known, that our emotions are evolutionary — they evolved in humans for a reason: survival. Anger and aggressiveness may seem largely out of place in the workplace or a romantic relationship nowadays, but thousands of years ago these emotions served very real purposes that helped humans live from day to day. Our sense of fear, for example, warned of us of danger that our prehistoric ancestors needed to survive — to avoid falling off a cliff or a cave where a bear resides. Some of these fears stay with us today but are, in evolutionary terms, not as irrational as they may initially appear.

Psychologists like to say that no emotion is a bad emotion, and in the grand scheme of things, this is largely true. Anger doesn’t occur in a vacuum, it occurs in a specific place and time and is usually triggered in us by a specific event or series of events. And while it may have served us very well in evolutionary terms (since all of us made it into the 21st century!), it serves us less well nowadays in everyday living.

I found this an enlightening article to read about how research suggests our brains work and employ emotions. It looks at a wide variety of emotions and describes what research is telling us about them. Be forewarned, however, that Miller often mixes theory with facts in the article and doesn’t always clearly delineate between the two.

Read the full article: Sad Brain, Happy Brain