Human Brain Mapping Services of Connectomics

A century on, subsequent studies have validated many aspects of this early ‘brain map’. We know for example that damage to Area 4 will consistently cause deficits to movement and Area 17 to sight. Using similar techniques, there have even been several new areas that have been added or subdivided from existing areas.

The Brodmann model is, however, limited in explaining more complex neurological functions.

For starters, the method by which the Brodmann map identified functional areas of the brain was unlikely to be completely accurate - just like the examination of the earth’s surface alone does not meaningfully assist in drawing country, state, and city boundaries.

Indeed, it does not say much about how different areas of the brain interact, just as a world map does not provide much insight into geopolitics. Yet we know now that these interactions are responsible for important processes such as comprehension, emotion, and thinking. When these processes are compromised, they are also responsible for mental and neurological disorders such as depression, autism, and schizophrenia - all of which, as a result, have been poorly understood.

Limitations of the Brodmann ‘brain map’:

• The physically observable differences between regions did not necessarily correlate with the functions they performed
• The model grouped multiple regions that actually performed distinct, often unrelated functions
• It does not to explain anything beyond very basic function such as movement and speech (and even then, did so simply)
• Studied only the gray matter of the brain, and not the white matter that wired it together
• Locations differed between different individuals - especially those with brain injury

However, while our technologies to help navigate street directions and to remain informed about world affairs have all grown drastically more powerful and accessible, most doctors and researchers have seen little changes to their tool kits to navigate and understand the brain.