Module 5
1 / 32

Module 5 - PowerPoint PPT Presentation

  • Uploaded on

Module 5. Sensation. Sensations. Sensation is direct input from sense organs Vision Hearing Vestibular system Taste Olfaction Touch. EYE: VISION. Structure and function 1. Gather and focus light Absorb and transform light waves into electrical impulses process called transduction.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Module 5' - laddie

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Module 5

Module 5



Sensation is direct input from sense organs

  • Vision

  • Hearing

  • Vestibular system

  • Taste

  • Olfaction

  • Touch

Eye vision

  • Structure and function

    1. Gather and focus light

    • Absorb and transform light waves into electrical impulses

    • process called transduction

physical energy

electrical signals

neural impulses

sent to brain for processing

Eye vision1

  • Structure and function

    • Vision: 7 steps

      • Image reversed/Light waves

      • Cornea

      • Pupil

      • Iris

      • Lens

      • Retina

Which 2 areas bend and focus

light into narrower beams?

Eye vision2

  • Structure and function

    • Cornea

      • bends and focuses light waves into a narrower beam of light

    • Pupil

      • allows light waves to pass into the eye’s interior

Eye vision3

  • Structure and function

    • Iris

      • controls the amount of light entering the eye

    • Lens

      • bends and focuses light waves into an even narrower beam

Eye vision4

  • Structure and function

    • Retina

      • extremely sensitive to light

      • begins the process of transduction by absorbing light waves

Eye vision5

  • Visual pathways: Eye to brain

    • Optic nerve

    • Primary visual cortex

    • Visual association areas

Eye vision6

  • Visual pathways: eye to brain

    • Optic nerve

      • nerve impulses flow through the optic nerve as it exits from the back of the eye to the brain

      • the exit point is the “blind spot” (Why don’t you notice the blind spot?)

      • the optic nerves partially cross and pass through the thalamus

      • the thalamus relays impulses to the back of the occipital lobe in the right and left hemisphere

Leading a person who is blind
Leading a person who is blind

  • Offer your assistance

  • Keep the person on the leader’s left

  • Allow the person to take your arm

  • Give clear/brief/accurate information

    People who are blind respond well to intelligence

    Demonstrate veering

Ear audition

  • Measuring sound waves

    • decibel: unit to measure loudness

    • threshold for hearing:

      • 0 decibels (no sound)

      • 140 decibels (pain and permanent hearing loss)

Baby crying

Rock concert

Ear audition1

  • Outer ear function

    • pick up sound waves and then send them down the auditory canal

Ear audition2

  • Outer, middle, and inner ear

    • Inner ear

      • contains two structures sealed by bone

        • cochlea: involved in hearing

        • vestibular system: involved in sensing the position of the head, keeping the head upright, and

          maintaining balance

Chemical senses cont

  • Tongue

    • Five basic tastes

      • sweet

      • salty

      • sour

      • bitter

      • umami: meaty-cheesy taste

Chemical senses cont1

  • Taste buds

    • shaped like miniature onions

    • receptors for taste

    • chemicals dissolved in saliva activate taste buds

    • produce nerve impulses that reach areas of the brain’s parietal lobe

    • brain transforms impulses into sensations of taste

Chemical senses cont2

  • Smell, or olfaction

    • Olfaction

      • called a chemical sense because its stimuli are various chemicals that are carried by the air

      • Function of olfaction

        • receptors, through transduction, transform chemical reactions into nerve impulses

Chemical senses cont3

  • Smell, or olfaction

    • Sensations and memories

      • nerve impulses travel to the olfactory bulb

      • impulses are relayed to the primary olfactory cortex

      • cortex transforms nerve impulses into olfactory sensations

      • Can identify as many as 10,000 different odors

      • we stop smelling our deodorants or perfumes because of decreased responding

      • called adaptation

Chemical senses cont4

  • Smell, or olfaction

    • Functions of olfaction

      • one function: to intensify the taste of food

      • second function: to warn of potentially dangerous foods

      • third function: elicit strong memories; emotional feelings


  • Touch

    • includes pressure, temperature, and pain

Touch cont

  • Receptors in the skin

    • skin

    • hair receptors - when first bent

      (after being bent=sensory adaptation)

    • free nerve endings – temperature and pain

    • Pacinian corpuscle – vibrations

      Somatosensory cortex (parietal lobe)

    • transforms nerve impulses into sensations of touch temperature, and pain

Module 5

  • What causes pain?

    • pain: unpleasant sensory and emotional experience that may result from tissue damage, one’s thoughts or beliefs, or environmental stressors

    • pain results from many different stimuli

Pain cont

  • How does the mind stop pain?

    • gate control theory of pain

    • nonpainful nerve impulses compete with pain impulses in trying to reach the brain

    • creates a bottleneck or neutral gate

    • shifting attention or rubbing an injured area decreases the passage of painful impulses

    • result: pain is dulled

Pain cont1

  • Endorphins

    • chemicals produced by the brain and secreted in response to injury or severe physical or psychological stress

    • pain reducing properties of endorphins are similar to those of morphine

    • brain produces endorphins in situations that evoke great fear, anxiety, stress or bodily injury as well as intense aerobic activity