A computing, neurology and biology team from these three centres has developed one of the most exhaustive studies carried out to date on the development of the human brain, by number of cases analysed and range of ages evaluated - ranging from babies to old age. 

In total, they have analysed 2944 images of Magnetic Resonance of brains, of healthy subjects aged between 9 months and 95 years old. Of all these people, 1,379 were women and 1,565 were men. The images belong to public database of nine European institutions.

In the study, they analysed volumes of the hippocampus, tonsilis, putamen, accumbens, globus pallidus, thalamus and caudate, in addition to cerebrospinal fluid, grey matter and white matter. 

Results have allowed to get the normal values of each brain structure for a certain age and sex. In this way, this work also offers a valuable tool for the diagnosis of neurological pathologies.
 
“This study stablish a reference framework; before a new image of MR, the medical professional can check it and compare if the different volumes are within normal or if, on the contrary, it detects some pattern associated with a disease. For example, a volume of the hippocampus lower than expected would involve a possible case of Alzheimer’s,” says José Vicente Manjón, a researcher at the ITACA Institute of the Universitat Politècnica de València.  

 Differences between men and women

In this study, there are also differences in the evolution of the brain of men and women. Among other results, they have checked how the speed at which the brain atrophies is greater in men than in women and age worse, especially after 80 years. Moreover, as a rule, the hippocampus -structure associated to the memory- usually has, a slightly higher volume in the case of women.

“We have also seen how the female brain reaches its peak volume earlier than in men’s, its brain structures mature earlier,” says Enrique Lanuza, of the Department of Functional Biology and Physical Anthropology of the Universitat de València.  In the case of white and grey matter and cerebrospinal fluid, there is not significant relative differences between them.

volBrain

To carry out this study, the researchers used volBrain, a software developed by UPV and CNRS in 2015 and now it is an international reference tool to study the brain and the advance of the neuroimaging research. In the last two years, volBrain has analysed over than 51,000 brains and has been used by more than 700 universities, hospitals and researching centres from around the world.

“Now, we are going to integrate the values of normality obtained in this work in volBrain, so that any researcher can use the system and automatically know whether the image of the study case, is within the parameters of normality or, if otherwise, warns of a possible pathology,” concludes José Vicente Manjón.

Reference
Coupé, P., Catheline, G., Lanuza, E., Manjón, J. V. and for the Alzheimer's Disease Neuroimaging Initiative (2017), Towards a unified analysis of brain maturation and aging across the entire lifespan: A MRI analysis. Hum. Brain Mapp., 38: 5501–5518. doi:10.1002/hbm.23743