Sponge: Set up Cornell Notes on pg. 41

Topic: 12.1 General and Special Senses

Essential Question:

2.1 Atoms, Ions, and Molecules

12.1 General and Special Senses

1. What is the major difference between General and Special Senses?

1. Name your 5 senses.2. There are two types of senses, general

senses and special senses, hypothesize which of the 5 senses belong in each category.

Pg. 40

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General Senses

General Senses are those with receptors that are widely distributed throughout the body

Ex: Skin, various organs, muscles, and joints, viscera

Which of the 5 sensory receptors goes with each type of general sense?

• Touch/Pressure • Mechanoreceptors

• Temperature • Thermoreceptors

• Pain • Pain receptors

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General Senses

General Senses can be divided into three groups:

• Exteroceptive senses – senses associated with changes at the body surface

• Ex: touch, pressure, temperature, pain

• Visceroceptive senses – senses associated with changes in viscera (internal organs)

• Ex: blood pressure stretching blood vessels, ingesting a meal

• Proprioceptive senses – senses associated with changes in muscles and tendons and in body position

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Special SensesSpecial Senses have more specialized receptors whose receptors are located in the complex sensory organs of the head

Based on their location, hypothesize which senses are “special senses”

• Smell• Chemoreceptors (olfactory receptors)

• Taste • Chemoreceptors (taste cells aka gustatory cells-located in taste buds)

• Hearing• Mechanoreceptors (hair cells)

• Vision• Photoreceptors (rods and cones)

Which type of receptor goes with each type of special sense?

Special and General Senses (5m25s)

Pg. 40 • Take 3-5 bullets about each sense

• Vision• Hearing• Taste• Smell• Touch

(Video in this order)

All senses work basically the same way:

• Sensory receptors stimulate neurons to send impulses along sensory fibers to the brain

• There the cerebral cortex forms a “perception”

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In your own words…

Explain what you think the difference is between

Sensation and

Perception.

Pg. 40

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SensesSensation is a feeling that occurs when brain becomes aware of sensory impulse based on new experiences or recalled memory

• The resulting sensation depends on which region of the cerebral cortex receives the impulse

Ex: a soft Touch

A pleasant sound

Small black lines

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SensationsProjection is a process in which the brain projects the sensation back to the apparent source • It allows a person to pinpoint the region of stimulation

• Exs: • The eyes see an apple• The nose smells an apple• The ears hear the crunch as we bite into an apple

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SensesPerception is a person’s view of the stimulus; the way the brain interprets the information

Ex: the feel of a hand

Classical music playing

Letters on an eye chart

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Pathways From Sensation to Perception (Example of an Apple)

Pg 40

Let’s take a look at how your brain “perceives” these optical illusions.

Write down the first picture you see.

Pushing the Limits: Sensation (8m 11s)