"Genetic" brain profiling in rugby

In a previous post on brain profiling, I've indicated that the concept is pseudoscientific and in fact has nothing to do with the differential functioning of the left and right hemispheres of the brain. I quoted Ned Herrmann, the originator of the concept, as follows: "The whole-brain model, although originally thought of as a physiological map, is today entirely a metaphor." I've further indicated that brain profilists consider their brain profiles to be metaphors, although you often have to read very carefully to distill that fact from their writings.

Now we have one group of brain profilists who claims to be able to construct "genetic" brain profiles. Nowhere in their work do I find the weasel word, "metaphor". A description of the work of Dr. Annette Lotter and Associates with the South African Springbok rugby team appears in the normally scientifically reliable South African edition of the Popular Mechanics (September 2007). The full article by Andy Colquhoun is available here.

The article has the normal left brain right brain pop psychology nonsense that you'll find in such articles. I've previously referred to this as whole-brain half-wittery.

It then goes further and describes how 32 genetically determined combinations of left right dominance of brain hemisphere, hand, foot, eye and ear, determine people's reaction to stress. Based on the genetic brain profile, Lotter and Associates claim that they are able to predict "blockages" persons will experience under stress. These "blockages" cause different parts of the brain to become inaccessible under stress.

I quote one example:

"(Rugby) Players with left-eye dominance are overly sensitive to body langauge, and if you know that, you can throw them of their game by pulling faces or making gestures. You might also wonder how they would react to the haka (the Maori war chant used by the All Blacks)"

No, this is not satire. Have a look below at the All Black haka referred to. If there was any validity to the claim, any left eye dominant player who faced the All Blacks, would go into a catatonic state! To my knowledge that has never happened.



I have been an active target pistol shooter for many years. Pistol shooting is the one sport where the participant's dominant eye is fairly noticeable. Face pulling and grimaces are very common when bad shots are fired (add to that that many of my fellow shottists are an ugly lot!), yet I've never seen a left-eye dominant shottist being phased by that. The fact that there are many left eye dominant shottists competing at the top level, is a Popperian falsification of Dr. Lotter's claim. That, however, is anecdotal and as everone knows, anecdotal evidence have little scientific standing.

Let's look at facts. Consider that about 36% of the general population is left-eye dominant, that 34% of right-handed persons and 57% of left-handed persons are left-eye dominant Bourassa, 1996). Those are the percentages of rugby players you would prefer not to select when playing the All Blacks!

The claim that left-eye dominant people are sensitive to facial expressions assumes that eye dominance has a specific and predictable relationship to hemispheric asymmetries, from which specific predictions can be made about behaviour. This is questionable. Eye-dominance and its relationship to the hemispheres of the brain is not a simple either-or matter, as it is well known that each eye is connected via the optic chiasm to both hemispheres of the brain and that each eye has two visual half-fields that project to different sides of the brain. Sally Springer and George Deutsch, in their authoritative book, Left brain right brain (1998, p.133), point out that the relationship of eye and ear preference to hemispheric asymmetry is not particularly strong.



Left-eye dominant rugby players cave in under the haka? I think not! But consider for a moment the position of a left-eye dominant player who is not selected for a team because his coach believed this pseudoscientific nonsense.

As to Lotter Associates general claim that depending on the genetic brain profile and the pattern of motor and sensory dominance, different parts of the brain would become inaccessible or develop blockages under stress, I know of no scientific evidence to support this. There are stacks of reliable information on the internet on stress and the brain, but in no reputable website do I find anything on brain blockages as described by Lotter and Associates.

This quote by Druckman and Bjork (1991) from the excellent report of the American Academy of Sciences, based upon research commissioned by the American Army, says it all:

Sports performance is a quintessential problem in complex motor, cognitive, affective, and attentional processes, and it depends on functions that are widely distributed throughout both cerebral hemispheres. Studies that characterize the cognitive, attentional, or motor components of sports as “left hemisphere abilities” or “right hemisphere abilities” are fatally flawed. Not only is it inherently insupportable to characterize sports abilities by brain hemisphere, it is also methodologically and logically flawed to narrowly localize these complex processes.

This and the previous report by Druckman and Swets (1988) are both available free online. Sporting bodies, even those with limited funds, have no excuse not to properly research approaches and fads they subject their players to. The Springbok team have a history of involvement with management fads. This included whole-brain half-wittery. They should also take heed of the Druckman and Bjork quote above.