From functional localization to functional networks


Patient H.M. (also see website about project HM: the brain observatory) is a famous case study taught in every introductory psychology textbook about a man who was unable to form new long term memories after surgery, while episodic, short-term and procedural memory remained intact. Or maybe you remember the more “sensational” story about Phineas Gage surviving an explosion which resulted in an iron rod piercing through his brain (more specifically through his left frontal lobe). Although Phineas Gage revealed intact brain functioning on a standard cognitive test battery, he suffered from marked personality changes. Cases as these, as well as other lesion studies (with a very special mention for Broca‘s elaborate examination of the brains of aphasic patients) provided valuable insights into the functional organisation of the cerebral cortex.

Technological advancements, like functional MRI, further expanded possibilities of localising functions to specific brain regions. Although nice colourful brain pictures were posted on multiple blogs and news sites (btw: I like colourful brain pictures, so no offence intended, hence my own use of such pictures) with red spots lighting up to indicate that groups of cells involved in a specific function were doing hard labour… despite this nice technological advancement, a similar increase in our understanding of human brain function was and is still lagging. Now new imaging techniques, like diffusion MRI, come to the forefront with new fancy pictures.

The work that has been done is great, it’s great to see how technology moves so quickly, but as you can see in the scientific community for the past decades, there’s now a shift in how these tools are used as well, or how data derived from these tools are analysed. Like looking at the brain from another point of view, but using the same technique. A shift from functional localization to functional networks. Research interests are now focused on exploring how different brain areas communicate with each other and guide certain functions or behavior and find out how changes in activity on the network level can reveal pathology.

I hope these changes in perspectives and our advancement in analysing this information will at one point move beyond the “fancy” pictures to “fancy” results.

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