1 / 32

Module 5

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.

laddie
Télécharger la présentation

Module 5

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Module 5 Sensation

  2. Sensations Sensation is direct input from sense organs • Vision • Hearing • Vestibular system • Taste • Olfaction • Touch

  3. 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

  4. p95 EYE

  5. EYE: VISION • 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?

  6. EYE: VISION • 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

  7. EYE: VISION • Structure and function • Iris • controls the amount of light entering the eye • Lens • bends and focuses light waves into an even narrower beam

  8. EYE: VISION • Structure and function • Retina • extremely sensitive to light • begins the process of transduction by absorbing light waves

  9. p96 RETINA

  10. EYE: VISION • Visual pathways: Eye to brain • Optic nerve • Primary visual cortex • Visual association areas

  11. p97 VISUAL SYSTEM

  12. EYE: VISION • 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

  13. 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

  14. Visual Impairment and the Artificial Eye

  15. 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

  16. EAR: AUDITION • Outer ear function • pick up sound waves and then send them down the auditory canal

  17. EAR: AUDITION • 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

  18. CHEMICAL SENSES (CONT.) • Tongue • Five basic tastes • sweet • salty • sour • bitter • umami: meaty-cheesy taste

  19. CHEMICAL SENSES (CONT.) • 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

  20. CHEMICAL SENSES (CONT.) • 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

  21. p107 OLFACTORY BULB

  22. CHEMICAL SENSES (CONT.) • 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

  23. CHEMICAL SENSES (CONT.) • 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

  24. Smell Memory

  25. TOUCH • Touch • includes pressure, temperature, and pain

  26. p108 SKIN

  27. 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

  28. PAIN • 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

  29. p112 BRAIN PAIN

  30. 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

  31. PAIN (CONT.) • 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

More Related