Penis Size and the Primitive State of Sexual Consciousness

On the Nature blog this week, there was a summary of an article originally posted in Proceedings of the National Academy of Sciences (PNAS) on the implications of penis size preference and evolutionary pressure for large penises.  If true that may explain why humans have the largest penis size of all primates.  Someone has apparently already figured out that male genitalia were the earliest developed physical traits in the animal kingdom.

In the experiment, researchers showed computer generated life sized projections of 53 frontal images of men of varying heights, flaccid penis size, and body type to a group of 105 heterosexual Australian women.  The women looked at the images and rated them for sexual attractiveness.   Since the original article is not accessible, the results on the Nature blog state that that a range of flaccid penis sizes and male body types were rated the most attractive.  At some point masculine body type (greater shoulder width to hip width) was more important.  There was not a direct correlation with penis size and attractiveness.  The graph of size versus attractiveness was described as an inverted U-shaped curve with attractiveness falling off at both extremes.  There were some remarks on the importance of this finding not the least of which that studies like this may make it easier to talk about an “uncomfortable subject”.  I doubt that the press will take such a nuanced approached.

As I read that last line, I thought about penis references in the popular culture over the course of my lifetime from Woody Allen films to Seinfeld episodes to morning radio shock jocks.  I have gone through the “sexual revolution” and noticed that very little has changed.  If anything the landscape seems to have shifted to a more male dominated perspective with the further objectification of women and much easier access to that content.  In some of that content there is a disturbing portrayal of serial violence (usually homicide) and sadomasochism even in prime time television.  All it takes is showing an MALSV (mature audiences, strong language, sexual situations, violence) disclaimer at the outset to broadcast a blend of sexual violence and gratuitous nudity.  The focus from business interests is producing as much of this content as possible combined with the legitimization of the pornography industry.  What is driving all of this?

There are two areas relevant to psychiatry that are the object of very little research and they are sex addiction and sexual consciousness.  Consciousness in general has not been much of a focus by psychiatry since the advent of DSM atheoretical descriptors that in effect limited the focus of study to extremes of human behavior.   The consciousness that I am referring to is the unique conscious state of individuals.  The current diagnostic system does not presume to diagnose individuals

Sexual addiction and other "behavioral addictions" like eating and gambling are all the rage right now.  The neurobiological theories of reward, initial impulse control involving positive positive reinforcement, and subsequent compulsive behavior based on negative reinforcement are thought to apply in traditional chemical addictions but can the same models apply to sexual behavior?  The problem is that there are vast uncharted areas connected to the midbrain and basal forebrain structures that are thought to be substrates for addictive behavior.  Not all of the details of neurotransmission within the system are known even though we have several cartoon versions.  An analysis from reference 3  suggests in a rat model of sucrose self administration that up to 28 regulatory proteins in various cell structures may form the basis for the signaling involved.  Despite several papers suggesting that behavioral and chemical addictions may have the same substrates, I have not seen any compelling evidence that this might be true.  If sex can be addicting, what are the risks of exposure and can we help people with serious problems involving their sexual behavior? 

The state of consciousness in psychiatry these days is at an all time low.  Biological reductionism and a poor understanding of the importance of modern psychoanalysis in exploring unique conscious states may be part of the problem.  The other part of the problem is a single minded focus on problems with human behavior that are clearly two standard deviations from the norm.  This basically leaves out the unique conscious state of the individual and the fact that many people are clearly affected by problems that can't be reduced to a psychopathological model.  Human sexual behavior and all of the behaviors it is associated with are excellent examples at both an individual and cultural level.   Those authors who have taken on this task; most notably the late Ethel Person, MD have described a continuum of male sexual fantasy and behavior from the perspective of psychoanalytic theory and treatment of associated problems.   One of the more interesting considerations to me is the omission of practically all considerations of fantasy and daydreaming in the DSM as if these important functions have no explanation and are not as grounded in prefrontal cortex as the working memory is.  Do we know the basic differences in the sexual consciousness of men and women?  Not from anything that I can find.

These considerations are as important for culture as they are for psychiatry and psychiatric research.  The current cultural attitude seems to be that we need a mechanical understanding of sex.  It is the mechanical approach that is presented as sex education in school.  Here are the parts, here is how they work, here is how you get pregnant, and here is how you get diseases.  No relevant discussion about associated emotions, human attachment, desire, or love.  No appreciation of scientific differences in the sexes.  No discussion about how the really big organ in the head is orchestrating everything.  Figuring out how to address these important issues is a lot more complicated than voting on the most attractive present day penis. 

George Dawson, MD, DFAPA

1.  Nuzzo R.  Bigger not always better for penis size.  Nature News April 8, 2013.

2.  Mautz BS, Wong BBM, Peters RA, Jennions MD. Penis size interacts with body shape and height to influence male attractiveness.  Proc. Natl Acad. Sci. USA http://www.pnas.org/cgi/doi/10.1073/pnas.1219361110 (2013). 

3.  Van den Oever MC, Spijker S, Li KW, Jiménez CR, et al. A Proteomics Approach to Identify Long-Term Molecular Changes in Rat Medial Prefrontal Cortex Resulting from Sucrose Self-Administration.  Journal of Proteome Research 2006 5 (1), 147-154

4.  Ethel Spector Person, MD.  The Sexual Century.  Yale University Press, New Haven, 1999.