Aim: What factors influence our sensitivity Aim: What factors influence our sensitivity? What role does the mind and body play in pain perception? DO NOW: Go Over Quiz – Statistics Read about Gate Control Theory HW: Meet in Step II

The Skin Senses skin – largest sensory system cutaneous senses (3 types of receptors) touch (mechanical energy / pressure against skin) temperature thermoreceptors – sensory nerve endings under the skin that respond to changes in temperature at or near the skin and provide input to keep the body’s temperature at 98.6 degrees Fahrenheit (heat = dominant) pain (adaptive for survival; intense stimulation of any sense produces pain) prostaglandin – stimulate receptors that cause the experience of pain (many painkiller reduce production) fast pathway  thalamus (fast response required) slow pathway  detour in limbic system (tells you to “slow down” your lifestyle – “nagging pain”) https://www.youtube.com/watch?v=FJeuK1Pl2bQ

Sense of Touch You will perform a 2 pt. threshold test on 1 partner. Randomly use all 4 tips to test the sensitivity of THREE parts. Record data on p.

Sensitivity Threshold Receptors located on skin Activated by energy Various parts of body differ in sensitivity Crucial features are more sensitive

Factors which can impact pain reception? endorphins – neurotransmitters (slow pathway) factors: motivation, expectation, decision factors women experience more pain

Gate Control Theory Brain controls our gate and our thoughts and feelings can influence pain some pain message receive higher priority than other messages higher priority let in and lower priority shut out! What was the old accepted view of the perception of pain? What is the gate control theory? What influences pain according to this theory? 2 - minutes http://www.youtube.com/watch?v=KRFanGInvlc

Ramachandran’s Mirror Trick Phantom Limb Ramachandran’s Mirror Trick Amputated body part but might still have feeling in the area Theories Brain is undergoing extensive sensory reorganization Revised Gate Control

How can we apply this to pain management?

Aim: How do we perceive the world through touch and taste? Do Now: What factors influence our perception of pain? Homework: Test Monday on Sensation and Perception ( Study Guide Due)

Taste sweet, sour, bitter, salty + umami or yummy or savory (L-glutamate) papillae – round bumps above the tongue's surface that contain the taste buds, the receptors for taste (replaced every two weeks) 10,000 taste buds (younger) 5,000 taste buds (older) Role of culture on taste perception 20% of us are super tasters (more taste buds)! Taste preferences begin in womb

Interaction of smell and taste Work with partner. 6 trials with eyes closed & using nose– have them identify 6 trials eyes closed and NO NOSE – have them identify Orange = Orange Cherry = red Strawberry = pink Lime = green Grape = purple Pineapple = white Lemon = yellow Licorice = black

Smell/ olfactory olfactory epithelium – the lining of the roof of the nasal cavity, containing a sheet of receptor cells for smell unique: neurons replace themselves after injury; don’t pass through thalamus  temporal lobes  various brain regions (including limbic system – linked to emotion and memory (LOVE!) Dog - 100 times lower levels

Kinesthetic Sense (MOP) – movement, orientation, posture not in specific organ; receptors embedded in muscle fibers and joints same pathways to brain as touch Tells us where our body parts are.

Vestibular Sense (MB) – movement and balance begins in auditory nerve, which contains both cochlear nerve and vestibular nerve for balance and movement vision used in addition (when everything in visual field is moving… generally WE are moving proprioceptive feedback – information about the position of our limbs and body parts in relation to other body parts Receptors in semicircular canals of inner ear – three fluid-filled circular tubes that lie in the three planes of the body right-left front-back up-down