Taste, Smell and more….

 After quiz have journals ready

 Students will be able to…  Demonstrate their understanding of the senses

 What is your favorite food to eat?  Why? Explain with detail.

 How do you know where sound is coming from?  Difference in time it takes to reach each ear

 What’s the difference?  Key Terms  Low pitch v. medium to high pitch  Nerve impulse rate to brain v. vibration on the basilar membrane

 Where is it located?  Above the cochlea – inner ear  What do the semicircular canals do?  Filled with fluid that moves in response to movement of head  Hair Cells respond to the movement  What is its function?  Maintaining balance

 What is it?  Sensory mismatch between info form vestibular system (head movement and eye sees no movement)  What are the symptoms?  Nausea, dizziness  What is Meniere’s disease  Malfunction of canals – viral infection of the inner ear  Symptoms – spinning and buzzing sounds  What is Vertigo?  Malfunction of canals  Dizziness and nausea

 Taste test….  Explain everything that happens when you are tasting the candy in your journal.  Include all of your senses at work and anything that comes to mind…including memories.

 Taste  Tongue  5 basic tastes – Sweet, salty, sour, bitter, umami  Surface of Tongue  Chemicals breakdown stimuli into molecules  Mix with saliva and run into trenches on surface  Stimulate taste buds  Taste buds  Look like onions  Produce nerve impulses that reach parietal lobe  Brain transforms into sensations of taste  Replaced every 10 days  Flavor  Combo of taste and smell

 Stimulus  Smell volatile substance (molecules in air)  Olfactory cells  Receptors in 1 inch square patch of tissue in uppermost part of nasal passages  Covered in mucus which dissolves molecules and stimulates cells  Cells trigger nerve impulses that travel to brain which interprets the smell

 Sensation memories  We can identify as many as 10,000 different odors  Adaptation goes into effect  Functions  To intensify the taste of food  Warn of dangerous foods  Elicit strong memories/feelings

 Pressure, temperature and pain  Half-dozen miniature sensors that are receptors  Change the pressure into nerve impulses and send to brain

 Skin  Outer layer  Thin film of dead cells, no receptors  Different shapes and functions  Hair  Middle layer  Free nerve endings wrap around base of each hair follicle  Follicles fire with a burst of activity when first bent  Sensory adaptation  Free nerve endings  Near bottom of skin  Nothing protecting them  Pacinian corpuscle  In fatty layer  Largest touch sensor  Highly sensitive to touch  Responds to vibrations and adapts quickly

 What causes pain?  unpleasant sensory and emotional experience from tissue damage, thoughts, beliefs, or environmental stressors  results from many different stimuli

 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

 Chemicals produced by the brain and secreted in response to injury or severe physical or psychological stress  similar to those of morphine  Brain produces in situations that evoke great fear, anxiety, stress, or bodily injury as well as intense aerobic activity

 Connected to pain centers in brain  Acupuncture  Thin needles inserted in various points on body’s surface – twirl needle  10 – 20 mins reduction in pain for some

 Identify and memorize the definitions of perception and sensation  On your worksheet label each image with an P if it is more of a Perception or an S if it is more of a Sensation.  If it is more of a perception explain what the illusion is and what is producing it.

 Essay – will count as 25 points towards your combined quizzes, worth 75pts, to make a test grade out of 100.  No Reading for homework…stepping away from book next week!  SEE YOU MONDAY!