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Sensation & Perception:
Our Other
Senses
• Goals  Describe how our senses of touch,
taste, and smell interact to form our
perceptions.
Touch
• Basic skin senses = pain, cold, warmth
pressure
(other sensations are combo of these four)
• Receptors located in our skin = detect touch
sensations
– More sensitive = more receptor cells =
larger areas on somatosensory cortex in
the brain
Touch
• Our brain significantly affects whether, and how,
we perceive pain.
• Gate-control theory = pain sent through small
nerve fibers in spinal cord, while non-pain is sent
through large nerve fibers
– Non-pain fibers can close the “pain gates” to
the brain
Gate Control Theory
Kinesthetic Sense
• Tells us where our body parts are in relation to one another and to
our environment
• Coordination
• Receptors located in
our muscles and joints
• = Proprioception
Vestibular Sense
• Tells us where our body is
oriented in space.
• Our sense of balance.
• Located in our semicircular
canals in our ears.
• Am I vertical? Horizontal?
Taste is a Chemical Sense
• Receptor cells on the tongue’s surface respond
to chemical structure
• Five tastes
– Sweet  Energy source
– Salty  Sodium essential to
physiological processes
– Sour  potentially toxic acid
– Bitter  potential poisons
– Umami  proteins to grow &
repair tissue
Taste Receptors
• Inside each little bump on the sides and top of
your tongue are 200 or more taste buds, each
containing a pore that catches food chemicals
• In each pore, 50 to 100 taste receptors project
antenna-like hairs that sense food molecules
Taste Receptors
• Taste receptors reproduce every week or so
• # of taste buds decreases with age
– Smoking & drugs also affect taste buds
• Expectations influence
brain’s response
• Linda Bartoshuk et al. (1994)
– 25% of pop. = “supertasters”
– 25% of pop. = “non-tasters”
Olfaction – Our Sense of SmellSmell
• Smell is also a chemical sense
• Olfactory receptors in upper
nasal passages detect
molecules in the air
• Odor molecules come in many
shapes and sizes, so we have many
different receptors to detect them
• Some odors trigger a combination
of receptors in patterns that are
interpreted by the olfactory cortex
• Odor molecules combine to
produce the 10,000 odors we can
detect
Sensory Interaction
• Taste and smell interact to create flavor
– If your sense of smell is blocked, foods will not
taste the same
• Synaesthesia  one sensation produces
another
– Hearing a sound
and seeing a color
– Number and a
taste sensation
Smells are primitive
• Pheromones!
• Why can we recognize
long-forgotten odors
and their associated
memories?
– Connection between
brain area receiving
info from nose and
limbic system
Extrasensory Perception (ESP)
• Claim that perception
can occur without
sensory input
• Clairvoyance =
perception of events
happening somewhere
remote from perceiver
• Precognition =
perceiving future events
(i.e. psychic)
Extrasensory Perception (ESP)
• Telepathy = perceiving
another’s thoughts
• Telekinesis = moving
objects with one’s mind
• Is ESP real?
– Difficult to test
– Research has not
replicated results,
therefore no evidence
exists