DK - WOW! The Visual Encyclopedia of Everything

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PREMOTOR CORTEX

Learned movement skills, such as playing tennis, are controlled and coordinated by

the premotor cortex. It tells specific muscles

to contract either through the primary motor cortex or, in some cases, directly.^4

PRIMARY MOTOR CORTEX

Most movements we make are controlled

by the primary motor cortex. Guided by information from the cerebellum and other brain parts, it sends instructions to muscles that move the skeleton instructing them

when, and in what sequence, to contract.^5

PRIMARY SENSORY CORTEX

Receptors in the skin for touch, pressure, vibration, heat and cold, and pain send

signals to the primary sensory cortex enabling us to feel those sensations. Our lips and fingertips have high concentrations of receptors, hence their sensitivity.^6

SENSORY ASSOCIATION CORTEX

Basic information about touch, pressure, and other skin sensations is passed on by the primary sensory cortex to the sensory association cortex. Here sensations are analyzed, stored, and compared with previous experiences. It enables us to identify objects by touch.

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PRIMARY VISUAL CORTEX

When light hits the retina at the back of each eye, its light detectors send signals to the primary visual cortex. Here those signals are interpreted as basic shapes, colours, and movements before being passed on to the visual association cortex.^8

VISUAL ASSOCIATION CORTEX

This is where information from the primary visual cortex about seen objects is interpreted and compared with previous visual experiences. The visual association cortex identifies what we are looking at and where it is in space, enabling us to “see” it.^9

CEREBELLUM

The cerebellum is responsible for producing smooth, coordinated movements of the body. It analyzes incoming information about the body’s current position and movement, then interacts with the primary motor cortex to precisely time muscle contractions.

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WERNICKE’S AREA

Usually located in the left hemisphere, Wernicke’s area gives meaning to words that have been heard or read. Named after the German doctor Karl Wernicke, it has a direct link to Broca’s area enabling us to speak the words we hear or see.^11

PRIMARY AUDITORY CORTEX

When sounds are detected by the two ears they send signals to the primary auditory cortex. Here the loudness, pitch (whether high or low), and rhythm of sounds are identified. That information is passed on to the auditory association area.^12

AUDITORY ASSOCIATION AREA

Sounds are “heard” in the auditory association area. Using information received from the primary auditory cortex, it pieces together the complete sound, and, by comparing it with sounds stored in memory, identifies it as, for example, music, speech, or thunder.

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