BRAIN FUNCTIONS AND THE SENSES
Sensing the World 64 65Sense areas of the cortex
Inputs from the sense receptors map to different
areas of the brain’s cortex. Although these areas
are separate, they can often react to inputs from
another sense. For example, visual neurons will
respond better in low-light situations if they are
accompanied by sound.SO
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PRIMARY^ TASTE
AUDITORY
AREA
CORTEX
Proprioception
The brain is constantly
processing information
from the joints and muscles that
tell it where the body is in space.
It keeps us upright and allows us
to make movements without
conscious effort, such as
walking up stairs.Ta s te
Taste is important
in determining what
is safe and nutritious
to eat. Taste receptors pick up
only five basic tastes: sweet, salty,
bitter, sour, and umami
(savory). We need our sense
of smell to help identify
a taste.Smell
Despite having only
400 smell receptors,
humans can detect up to a
trillion different odors. Smell
is important for survival as it
warns us of hazardous
substances or events, such
as something burning. It also
plays a key role in taste.HOW MANY
SENSES ARE THERE?Including the six senses
described here, scientists
think there may be as many
as 20 senses, based on
the number of different
receptor types in
the body.
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US_064-065_Sensing_the_world.indd 65 20/09/2019 12:33