How did scientists work out which parts if the brain did what? ...

[Jesse_J]

I'm doing my science homework, i need to writ an article for the science sectin of the newspaper about how scienctists worked out which part of the brain does what. Help pleeaaseee x

[j_sun]

it actually started way back....
during the world war..the japanese did the same as Nazis..they captured prisoner of wars
and cut open their scalp while alive!!! then they kinda cut some part of the brain nerves to see how the prisoners react.
for example...if they go blind...it means that area of brain is responsible for visual.
its actually very very cruel to collect so much data..imagine hw many ppl have been through that intensity of pain.
however on a slightly brighter side....it has greatly contributed to our modern neuro-science.

[aero]

A programme was recently shown on television concerning a person who had only one half of a brain, yet was able to live more or less normally, other parts of the brain having taken over the functions of the missing half. It may be that the different regions of the brain do not function quite in the way we have previously thought.

[Hungry!]

There have been lots of different things, most of the earliest ideas came from looking at the brains of people who had been injured, knowing that there were certain things regarding personality or intelligence that they could no longer do. Lots of animals were used in experiments, purposefully given brain damage to see how this affected their behaviour and abilities.

In recent decades there have been some inventions which have given a much better understanding of how human brains function. These are electronic maps called CT (computer tomography) and PET (positron emission tomography). CT scans (called "cat" scans) are kind of like an x-ray of the brain, but PET scans give a 3D picture and can be used while the patient is awake to show brain activity in response to stimuli. For example, they'll ask the person to think of an apple, and watch what parts of the brain are active, then they'll get them to click their fingers, then think about clicking their fingers, and compare how the brain activity differs between clicking fingers or just thinking about clicking them

[aero]

In the early years, mostly by comparing damage to the brain with the effects that damage had on the person. A bit like taking a chip out of your computer and seeing what function stops working. Google Phineas Gage, it's a really interesting story.
They also worked a lot on cats and monkeys. The advantage with using animals was that you could damage the brain or stimulate it and see what happens, without the moral problems involved with experimenting on humans (this was before the animal rights movement got started).

Other methods that have been used are EEG (looking at electrical signals coming from the brain), electrically stimulating parts of the brain in awake patients during brain surgery, MEG (like EEG but with magnetic fields coming from the brain), PET and perhaps the most powerful method - fMRI.

[coco]

At the earliest time there was a famous case study - Phineas Gage, rail worker, was involved in an explosion and a piece of metal went throught the front of his head and destroyed the frontal lobe - he was originally a friendly and efficient worker but turned into a jerk who lost his temper a lot and was late all the time. This suggested that different parts of personalities were in different bits of your brain.

Before the MRI, PET, MEG and EEG scans they basically just worked out what did what by studying people with bad head injuries and seeing which parts of their personalities or abilities were dysfunctional according to which but if your skull was bashed in. Now we have a pretty good idea what happens where using the scanning methods previously mentioned.