Cognitive dysfunctions

I once attended a course "Funktionsstörungen/Dysfunctions" at Aachen University, that dealt with disorders of several functions of the brain and insights that can be concluded therefrom. A recent TED talk by Vilayanur Ramachandran picked-up that topic and is definitely worth watching.

In the first lesson of the course I was afraid that it's just about memorizing a bunch of diseases and its indications. It was, however, an illuminating course about how different brain areas and their function can be identified by looking at very rare neurological diseases. Contrary to most empirical sciences – where an offbeat data item is usually treated as an "error" – these individual cases are of great value in understanding how our brain works.

An interesting example is prosopagnosia. People suffering from prosopagnosia cannot identify people by their faces, despite having normal vision and being capable of identifying objects other than faces. As they can also recognize people via different modalities (e.g. via voice), this leads to the conclusion that there is a separate brain area for identifying faces visually.

Mr. Ramachandran talks about the Capgras delusion, witch is somewhat similar to prosopagnosia, synesthesia (when people hear color or smell sounds), and a possible cure to phantom limb pain.

Watch his talk.