1. Sensory System

2. Sensory channels Discriminative: spatial and temporal localization of events Affective: pain and positive emotional experiences  monitoring internal and external environment

3. Multisensory Experiences Interconnecting networks Most information as quickly as possible Must integrate that information Experiment 1: flavors of liquid Experiment 2: jellybean flavors

4. Experiment 1 Observe the liquids, record your hypotheses in the table. Place a cut straw into cup A. Put a finger on the exposed end of the straw, trapping liquid in the straw. Open your mouth, placing the straw over your tongue, and release your finger from the top of the straw. Do not allow the straw to touch your tongue. Taste the solution and write down the flavor in the table. Use a different straw for each solution, repeating the same procedure for each liquid.

5. Experiment 2 Obtain a jelly bean Record your hypothesis about the flavor Hold your nose, eat the bean. Record taste. Release your nose, what do you taste now?

6. Receptors Specialized area of a sensory neuron that detects a specific stimulus.

7. 5 types: Chemoreceptors Thermoreceptors Mechanoreceptors Photoreceptors Nocioceptors Stimulus

8. 5 types: Chemoreceptors: changes in chemical concentrations Thermoreceptors: changes in temperatures Mechanoreceptors: changes in pressure or movements of body fluids Photoreceptors: light energy Nocioceptors: tissue damage or distension associated sense(s)…

9. Experiment 3 Peppermints Sour patch kids Hold nose, eat, record flavor

10. Sensation Conscious awareness of incoming sensory information

11. Perceiving a Sensation Stimulus  receptor  sensory nerve  special area of brain

12. Aristotle Illusion: Experiment 4 Cross your middle finger over your index finger. Place a marble on the table top and place the pads of your crossed fingers on top of the marble. Look away from your hands, and then slightly roll the marble back and forth in the crevice of your crossed fingers. Record your findings and answer questions.

13. Experiment 5: wooden dowel tapping Follow instructions as given

14. Aristotle’s Illusion Usually fingers aren’t crossed when manipulating objects Brain doesn’t account for it – felt two marbles

15. Dowel Rods Sense of touch not altered – perception was Harder to tell which was tapped first when crossed arms Both crossed (arms and dowel rods) – easier to tell which one was tapped first.

16. Both activities Illustrate a limitation to PERCEPTION of sense of touch. you are “hardwired” for “normal” operating circumstances

17. Experiment 6: vinegar Follow procedure as given

18. Adaptation If a receptor is continuously stimulated, sends fewer signals to the brain. Why would this be advantageous? Receptors vary in ability to adapt: – Pressure and touch: rapid – Nocio- not at all – Body position and blood chemistry – slow

19. Projection Process by which the brain, after receiving a sensation, refers that sensation back to its source.  pain

20. General Senses Pain Touch and pressure Temperature Proprioception

21. Pain: main triggers Tissue injury – releases particular chemicals Oxygen deficiency – heart attack and admin of oxygen Stretching or deformity of tissue – mechanical rather than chemical (bloating/distention) Referred pain – shared sensory pathways

22. Pain medications – how do they work?

23. Touch and Pressure Tactile receptors Mostly on skin First sense to develop in utero Essential to growth and development

24. Kangaroo care Skin to skin contact from early on Warmth and physical contact Causes neurobiological changes: – Calming – Stabilizing temperature – Improve feeding  Failure to thrive

25. Temperature Scattered widely throughout body, many in skin Cold: 10 o C – 25 o C (50 o F – 76 o F) Heat: 25 o C – 45 o C (76 o F – 112 o F) Pain receptors stimulated on either end of scale Adapt quickly

26. People from Phoenix…versus people from Chicago…

27. Experiment 7 Cooling effect of menthol? – Halls (or any cough drop with menthol) – Drink a hot beverage – do you know its hot?

28. Proprioception Sense of orientation/position Knowing where your body is in space Can locate a body part without looking at it Essential role in maintaining posture and coordinating body movement

29. proprioreceptors Located in muscles, tendons, and joints Also in inner ear (for equilibrium) Cerebellum receives messages (coordinating skeletal muscle activity). Movement and position info sent to parietal lobe of the cerebrum

30. Finding Fingertips Close your eyes and raise both hands above your head Keep the fingers of your left hand completely still With your right hand, quickly touch your index finger to your nose, then quickly touch the tip of your thumb of your left hand (with your right index finger). Quickly repeat the entire process attempting to touch each fingertip. Switch hands and try again.

31. “X” marks the spot Mark an X on a piece of paper. Pencil in hand, raise your hand above your head, close your eyes, and make a dot as near as possible to the X. Open your eyes and check your success. Repeat several times. Try it with the other hand.

32. Handwriting Analysis Lined sheet of paper, write proprioception. Place your pencil on the same line next to the written word, close your eyes, and write proprioception again. You can try it again and see if you improve. You can try it again with your nondominant hand.

33. Special Senses Smell: olfactory cortex Taste: gustatory cortex Sight: visual cortex Hearing: auditory cortex Balance: cerbellum