Scientists build statistical map of nuclei in the human thalamus

A major breakthrough in how we map the human thalamus is reported in the journal NeuroImage.

A research team led by UCL and the Basque Centre on Cognition, Brain and Language (Spain), and involving collaborators at the Massachusetts Institute of Technology, Massachusetts General Hospital (Harvard Medical School), the University of Castilla-La Mancha in Spain and the Technical University of Denmark, has succeeded in building a highly detailed probabilistic atlas to map the individual nuclei within the human thalamus using microscopic images of human tissue (histology). This has major implications for improving our understanding of the interactions between the thalamus and the rest of the brain, in healthy individuals as well as in several highly prevalent neurological disorders such as Alzheimer’s disease, schizophrenia and dyslexia.

The thalamus is an area of the brain which has a number of functions, including relaying sensory and motor signals, regulating sleep, consciousness and alertness, and controlling spoken language. The researchers used high resolution MRI scans and histological sections from autopsy samples to build a highly detailed atlas of the human thalamus, and develop a companion image analysis method enabling the application of the atlas to the automated analysis of the nuclei of brain MRI scans from living people.

Juan Eugenio Iglesias, the UCL researcher who led the study, explains the significance of the breakthrough: ‘Looking at the individual nuclei rather than the whole thalamus allows for far more detailed analysis, enabling us to understand so much more about how the brain works, not only in healthy individuals, but also in subjects who have developed a disorder where the thalamus plays a major role. Fors instance, iif you look at the whole thalamus in patients with Alzheimer’s and compare them with healthy controls, there is barely any difference. But if you look at the specific nuclei, you can detect important differences between the two groups.

‘We want the global neuroimaging community to be able to benefit from this straight away, so we are not keeping it to ourselves. Both the atlas and companion software are now publicly available as part of the open source neuroimaging package FreeSurfer, and there’s free support available through the FreeSurfer mailing list.

The research was mainly funded by a Marie Curie Individual Fellowship, sponsored by the European Commission, and by the Spanish Ministry of Economy and Competitiveness (MINECO).