Chapter 3: Sensation & Perception PDF

**CHAPTER 3** **SENSATION & PERCEPTION** **SENSATION** - The basic experience of stimulation of the body's senses: sight, hearing,smell, taste, touch & balance. - Sensation is the process of detecting and encoding physical stimuli from the environment through our sensory receptors. T...

**CHAPTER 3** **SENSATION & PERCEPTION** **SENSATION** - The basic experience of stimulation of the body's senses: sight, hearing,smell, taste, touch & balance. - Sensation is the process of detecting and encoding physical stimuli from the environment through our sensory receptors. These receptors, located in our sense organs (like the eyes, ears, nose, tongue, and skin), convert physical energy (light, sound, etc.) into neural signals that are sent to the brain. A. ***THE SENSES*** 1. ***THE EYE*** - - ***KEY PARTS OF THE EYE*** **Retina** - **Cornea:** - **Pupil:** - **Iris:** - **Lens:** - **Rods:** - **Cones:** - · **Optic Nerve:** - *THE VISUAL PROCESS* 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. THE COLOR VISION & THEORIES COLOR - HUE - SATURATION - BRIGHTNESS - THEORIES RELATED TO VISION 1. TRICHROMATIC THEORY - - 2. OPPONENT-PROCESS THEORY - - 3. DUPLICITY THEORY - **Rods**: Active in low light, such as at night **Cones**: Active in bright light and responsible for color detection 2. ***THE EAR*** - - - SOUND WAVES - the mechanical vibrations in the air. THREE MAJOR PARTS OF THE EAR 1. OUTER EAR - a. b. glands are present in this Canal, which secretes Earwax. 2. MIDDLE EAR - a. \- super sensitive to the vibrations of the ear. b. b1.HAMMER (MALLEUS)- is a tiny bone that looks like a hammer that is located next to the eardrum. b2. ANVIL (INCUS) -the tiny bone next to the hammer. b3. STIRRUP(STAPES)- it also vibrates and passes the compressional w aves to the inner ear. 3. THE INNER EAR (LABYRINTH) - - a. - it consist of many hair cells which is in basilar membrane in which ORGAN OF CORTI rests and when the fluid in it moves, it moves these tiny hairs creates nerve signal that get sent through the auditory nerve into the brain. b. \- When you move your head, the fluid in the canals moves, which bends hair cells in the canals. These hair cells send nerve signals to your brain, which then tells your body how to stay balanced. THE AUDITORY SYSTEM SOUNDS OR SOUND WAVES - - PITCH - AMPLITUDE - - Zero decibels would be the softest noise detectable by humans - Prolonged exposure to sounds above 80 dB can cause permanent damage to the ears, as can even brief exposure to sounds near the pain treshold which is 100-130 db. THEORIES OF HEARING 1. PLACE THEORY - - - 2. FREQUENCY THEORY - - - 3. ***THE NOSE*** - - - - *OLFACTORY EPITHELIUM* - The outside parts of your nose (the parts you can see) consist of bone, cartilage and fatty tissue. They include your: **Nasal root:** The top part of your nose located between your eyebrows, where your nose connects to your face. **Nasal apex:** The bottom part of your nose that houses your nostrils and tapers off into a rounded tip. **Nasal dorsum:** The middle part of your nose, between your nasal root and nasal apex. The inside of your nose has several complex structures, too, including: **Cilia:** These tiny, hairlike structures trap dirt and particles. Then, they move those particles toward your nostrils, and eventually out of your body. Cilia differ from nose hairs. You have them throughout your respiratory tract. **Nasal cavities:** These are hollow spaces where air flows in and out. You have two of them --- one on each side. Mucus membranes line your nasal cavities. **Olfactory Nerves: **These cells communicate with your [brain] and give you your sense of smell.And is located on the olfactory bulb which is in the upper of nasal cavity in your olfactory epithelium. **Nose hairs:** The hairs inside your nose trap dirt and dust that would otherwise end up in your nasal passages. **Nostrils (nares)**: Your nostrils are holes that lead to your nasal cavities. **Mucus Membrane:**They produce the mucus that keeps your nose moist and warm **Septum:** This is the bone and cartilage that separate your nasal cavities. The lower part of your septum sits between your nostrils. **Turbinates (conchae):** These folds warm and moisten air after you breathe it in. They also aid in nasal drainage. You have three pairs of turbinates along each of your nasal cavities. 4. ***THE TONGUE*** - - - - - a. b. c. d. 5. ***THE SKIN*** - i. - ii. - iii. FOUR SKIN OR CUTANEOUS SENSES: 1. PRESSURE (touch) 2. PAIN 3. WARMTH 4. COLD/HOT B. **SENSATION** - - **CHARACTERISTICS OF SENSATION:** 1. **SPECIFICITY OF SENSORY STIMULATION** - 2. **TRANSDUCTION** - - 3. **THRESHOLD** - - - 1. - --------- -------------------------------------------------------------------------- VISION A candle flame at 30 miles on a dark, clear night HEARING A tickling watch at 20 ft under quiet conditions TASTE A teaspoon of sugar dissolved in two gallons of water SMELL One drop of perfume diffused throughout three rooms TOUCH The wing of a fly falling on your cheek from a distance of 1 centimeter. --------- -------------------------------------------------------------------------- 2. - 4. **INTERRELATEDNESS OF SENSES** - - C. **PERCEPTION** - - **CHARACTERISTICS OF PERCEPTION:** 1. **LIMITED TO SENSORY DISCRIMINATION** - - - Thus it affects our abilityto discriminate among stimuli environment. 2. **PERCEPTION IS SELECTIVE AND SUBJECTIVE** - - A. - - - - B. - - 3. PERCEPTION IS CONSTANT - - - PRINCIPLES OF PERCEPTUAL CONSTANCY - - - - 4. PERCEPTION HAS ORGANIZING TENDENCIES - - - - - - - - - - - - - - - - - - - D. **MOTION PERCEPTION** - Focuses on both real movement and apparent movement (occurs when an object is stationary but they tend to perceive it to be moving). E. **ILLUSIONS** - Occurs when two objects produce exactly the same retinal image but are perceived as different images.\\ - Perceptual constancies are among the factors thought to be responsible for illusions. F. **EXTRASENSORY PERCEPTIONS** - Is perception that occurs without the use of any known sensory process. - Main Categories of ESP: - - - -