How emotions have served an evolutionary purpose
Good Reasons for Bad Feelings: Insights from the Frontier of Evolutionary Psychiatry by Dr. Randolph M. Nesse digs into the science of evolution to understand why mental illness persists. He explains that while the illnesses themselves are not evolutionary adaptations, our vulnerabilities to these illness may actually have evolutionary purposes.
He takes the rather refreshing approach of acknowledging both the good and the bad of the field of psychiatry. For example, he discusses the flaws of the DSM without throwing the baby out with the bathwater. He argues that the biggest problem with current psychiatric research is the lack of acknowledgement of the role that precipitating situations play.
From an evolutionary psychiatry perspective, there are six key areas of vulnerability:
- a mismatch of genes to current conditions (e.g. diet, alcohol, other substances we’re exposed to)
- infectious organisms evolving more rapidly now than in the past
- limits on what natural selection can do to select for/against certain characteristics
- trade-offs where vulnerability in one area is sacrificed for decreased vulnerability
- evolution selects for reproduction rather than health
- the defensive function of certain responses (e.g. pain)
The author argues that emotions have developed to promote survival and reproduction by increasing our ability to cope with certain situations. In a situation of potential danger, anxiety would increase the chances of survival, while happiness could mean getting eaten by a sabre-toothed tiger. The book includes a tree diagram, with different situations branching out to leaves of different emotions that would be suited to those situations. This can be found on the author’s ResearchGate page.
The smoke detector principle is proposed as a reason what may seem like unnecessarily strong responses. Just like a smoke detector, protective responses like pain or vomiting get triggered whenever the potential benefits outweigh the downsides, regardless of whether that may cause some false alarms.
The book is very thorough, offering examples of numerous research studies. These are presented in an easily understandable manner. However, the second half of the book seemed to get a bit bogged down in detail. I say this at least in part because for the most part I found the earlier part of the book more personally relevant/interesting. Chapters on things like social interactions and sex may have be appealing to some readers, but they just weren’t what I was looking for from the book.
In terms of specific mental illnesses, the author suggests that people with psychosis have a lack of repression (i.e. the concept proposed by Freud), as do people with OCD, although in a more focused way. A chapter on eating includes the assertion that eating disorders are not a result of genetic abnormalities, but are caused by abnormal environments.
This book definitely included some interesting concepts and information. Overall, though, for me there was just more detail than I wanted about too many things that I just wasn’t that interested in. I think that’s in part a reflection of the book but also in large part this just not being the mental illness-focused book that I had been hoping it would be.
I received a reviewer copy of this book from www.netgalley.com.
Originally published at http://mentalhealthathome.org on May 8, 2019.