3 Studying the brain

Neuroscience is the study of the brain and the nervous system. The earliest studies involved people with brains that had been damaged. Correlating the damage with observed impairments allowed scientists to build up a map of the brain, noting which regions are responsible for different tasks.

A pioneer in this field was a French physician, Pierre Paul Broca. In 1865, he published his results from studying twelve patients who all had difficulty in articulating speech, but who were otherwise able to comprehend language. His autopsies showed damage in the same area of the brain, suggesting its link to speech production. This region is now called Broca’s area.

Figure 5 Broca’s area (shown in red)

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This is an animated gif, showing a rotating translucent skull, the brain visible within. A small region on the exterior of the brain is marked in red. It is located on the side of left hemisphere towards the front.

Figure 5 Broca’s area (shown in red)

While specific brain regions are principally devoted to certain functions (as seen in Figure 6, and in Video 3 earlier), neuroscientists today are discovering that complex functions require many different regions across the entire brain to work together, and that these locations in the brain are more flexible than previously believed.

Figure 6 Principal functional regions of the human brain – the four lobes of the cerebrum

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This diagram depicts the four main lobes of the cerebrum in different colours. These are labelled and the key functions of each is listed: The upper frontal region is the frontal lobe, which comprises much of the front third of the cerebrum. It has a role in controlling movement and language, and is involved in higher level cognitive skills such as reasoning and planning. The upper rear region is the parietal lobe. It is important for processing information about touch and for spatial awareness. Beneath these two regions is the temporal lobe, which is important for processing auditory information, speech and memory. At the rear of the brain is a smaller region called the occipital lobe, which is primarily responsible for the processing of visual information.

Figure 6 Principal functional regions of the human brain – the four lobes of the cerebrum

So far, the brain has been discussed on the macroscopic scale. But what about the microscopic scale?