The gifted brain is rather energy saver

… Who never had a report card with the mention “Could perform better ?” because, clearly, one did not get exhausted for performing as well as (if not  better than) others ? Or how many times did you answer (vageuly guilty) “Well, that was easy… wasn’t it ?” as others were glancing at you with disbelief ?

White and grey matters… matter in what “makes” giftedness, particularly for data acquisition and processing.

But researchers also discovered that by processing a similar task, a gifted brain did consume less energy than a “normal” one.

I already mentioned a study run by the French National Scientific Research Center published in 2002 « L’état de la recherche sur les enfants dits « surdoués » (State of the art of the research undertaken about children known as “gifted”). Chapter 3 is a  « Contribution of the developmental neuropsychology to the study of high potential subjects» . It was written by Isabelle Jambaqué (P. 48 to 60 of the report, including the bibliography).

Page 50, it is mentioned that «Functional Brain Imaging works showed (thanks to PET – Positron Emission Tomography), a lower glucose consumption in high potential individuals as they were processing verbal and non verbal tasks (Haier et al. 1988, Parks et al.1988) ».

Since late 80’s Haier ran numerous studies  related to this subject.

As an article published in Scientific American in August 2008 reports it :  “  The researchers used positron-emission tomography, which measures glucose metabolism of cells, to scan the brains of eight young men while they performed a nonverbal abstract reasoning task for half an hour. They found that the better an individual’s performance on the task, the lower the metabolic rate in widespread areas of the brain, supporting the notion that efficient neural processing may underlie brilliance. And in the 1990s the same group observed the flip side of this phenomenon: higher glucose metabolism in the brains of a small group of subjects who had below-average IQs, suggesting that slower minds operate less economically.»

In the article “Giftedness and the brain“, Christian Hoppe and Jelena Stojanovic also refer to Haier’s works. They also bring some precisions regarding the “differences in brain activation [whic] are often related to task difficulty (Haier et al., 1992; Larson et al., 1995), which partly depends on subjective capability. When working on easy tasks, talented

participants show less metabolic activation than nontalented participants, providing

the evidence for the ‘neural efficiency’ account. However, applying a more difficult task revealed more activation in talented individuals, supporting the ‘neuronal resource’account. »

Reference studies  :

Haier, R.J., Siegel, B.V. Jr, MacLachlan, A. et al. (1992). Regional glucose metabolic changes after learning a complex visuospatial/motor task: A positron emission tomographic study. Brain Research, 570, 134–143.

Haier, R. J., & Benbow, C. P. (1995). « Sex differences and lateralization in temporal lobe glucose metabolism during mathematical reasoning”

Gerald E. Larson, Richard J. Haier, Lori LaCasse and Kay Hazen (2002) “Evaluation of a “mental effort” hypothesis for correlations between cortical metabolism and intelligence“

Some clues : Energy consumption by the brain is 230-247 calories, based on 17 calories/gram and human brain sizes of 1,350-1,450 grams.  During periods of peak performance, adults increase that energy consumption by up to 50%, according to psychology lecturer Mark Moss, of the University of Northumbria.

While this may not seem an extraordinary amount of energy, the brain may use 30% of a body’s total energy, while being only 2 to 3% of total body mass.

Moss cites the original 1986 work of Siebert, Gessner, and Klasser on the energy supply of the central nervous system in his thesis.  The thesis, particularly the chapter 1 introduction, is a good and not overly technical discussion of what we know about brain activity, including descriptions of how PET scans are being used to monitor glucose consumption in the brain.   University of Northumbria : “Oxygen Administration, Cognitive Performance and Physiological Responses,” (Mark C. Moss,  PhD Thesis 1999) http://psychology.unn.ac.uk/mark/chapter1/chap1.htm

Here the full text of a communication (13 pages including bibliography) on “ Individual differences in general intelligence correlate with brain function during nonreasoning tasks “  by  Richard J. Haier*, Nathan S. White, Michael T. Alkire College of Medicine, University of California, Irvine, – USA –   Revised version january 2003.

Here the site of the Brain Performance and Nutrition Research Centre (BPNRC) University of Northumbria (list of publications on the site)