Other Senses

Taste

• Papillae – small bumps on the tongue that have taste buds in them.

• Taste buds - taste receptor cells in mouth; responsible for sense of taste.

LO 7.6 How do the senses of taste and smell work, and how are they alike?

• Gustation - the sensation of a taste.

• Five primary taste sensations have been identified. – Sweet – Sour – Salty – Bitter – Umami

• recent identification by researchers• sensation is triggered by glutamate

Taste

• Individuals vary in their capacity for experiencing taste sensations.

• Nontasters (fewer tastebuds)

– unable to taste certain sweet and bitter compounds

• Supertasters (more tastebuds)

– taste sweet and bitter compounds with far stronger intensity than other people

Taste

Smell

• Olfaction (olfactory sense)– Sense of smell.

• Olfactory bulbs– Areas of the brain specifically dedicated

to receive information from the olfactory receptor cells.

• At least 1,000 olfactory receptors.– Each have about a half dozen to a dozen

little “hairs” (ciliar) that project into the cavity and send signals to the brain.

LO 7.6 How do the senses of taste and smell work, and how are they alike?

Somesthetic Senses

• Somesthetic senses - the body senses consisting of the skin senses, the kinesthetic sense, and the vestibular senses.– Soma = body– Esthetic = feeling

Touch

• Types of touch–Pressure–Warmth–Cold–Pain

• Sensation of hot

Touch

• Tactile (touch) information is conveyed to the brain when an object touches and depresses the skin.– One or more of several types of receptors

are stimulated.– Touch messages are sent through nerve

connections to the spinal cord.– The message is relayed next to the

somatosensory cortex of cerebrum.

Pain

• Pain can be a valuable warning and a protective mechanism.– Pain motivates people to tend to an

injury, to restrict activity, and to seek medical help.

Pain:The Gate Control Theory

• An area in the spinal cord acts as a gate and blocks or transmits pain messages to the brain.

• Pain messages are carried by small, slow-conducting nerve fibers.

• Large, fast-conducting nerve fibers carry other sensory messages.

LO 3.11

Pain

• Distraction can be effective with short-term pain, but not long-term pain.

• Endorphins are natural painkillers produced by the body.– block pain and produce a feeling of well-

being– Some individuals release endorphins

when they think they are receiving pain medication.

• Kinesthesia sense– Sense of change in body position

• Vestibular sense– Movement of fluids in the inner ear caused by head or body movement

– Gives sense of equilibrium and balance