How did we manage to map the brain and figure out what each part controls?


Just to clarify, im not really curious about the actions it controls, but im more curious how we figured out where those actions happens in the brain. Like for example, how did we figure out that the frontal lobe is associated with emotions etc?

In: Biology

Most of the historical information on the function of specific parts of the brain was first discovered by looking at people who had lost those parts of their brain (due to a stroke, physical injury, or whatever else) and seeing what functionality they lost. Someone who lost their Broca’s area wasn’t able to speak, which means that the Broca’s area is used for speech, or someone with a frontal lobe injury had reduced emotions – that kind of thing.

Since then, directly stimulating part of the brain with physical contact, electricity, very high-power electromagnets, etc. and observing the results has also been used – basically the scientific version of “poke it with a stick and see what twitches”. Obviously this is done on animal models more than on humans.

Most recently, we can use radiographic techniques like fMRI and PET scans to see the areas of the brain with increased blood flow during specific activities – that’s where the “brain activity scans” you might have seen around come from.