Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Unit 4: Sensation Sensation: The process by which sensory receptors (in eye, ear, etc.) receive and are stimulated by stimulus energies from the environment. Perception: The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events. Bottom-up-processing: Analysis that begins with the sense receptors and works up to the brain's processing of the information. Top-down-processing: Information processing guided by higher-level processes, such as our expectations. Absolute Threshold: The minimum stimulation needed to detect a particular stimulus 50% of the time. Signal Detection Theory: Predicts how and when we detect faint stimuli (dependent on experience, expectations, motivation & fatigue. Subliminal Stimulation: Stimulation below one's threshold of conscious awareness. Research reveals a subtle, fleeting effect on thinking, but no effect on behavior. Difference Threshold: The minimum difference between two stimuli required for detection 50% of the time. It is also called the just noticeable difference or JND. It is based on Weber's Law: The difference threshold is in proportion to the strength of the original stimulus. Sensory Adaptation: Our diminishing sensitivity to unchanging stimuli. Selective Attention: The focusing of attention on specific stimuli, while ignoring other stimuli (e.g., the cocktail party effect). Transduction: The transforming of stimulus energies (i.e., light waves, sound waves) into neural impulses. VISION & LIGHT ENERGY Wavelength: Distance from the peak of one light or sound wave to the next. Wavelength determines HUE or color in vision and Pitch in audition. Shorter wavelengths are bluish in color, while longer wavelengths are reddish. Amplitude: The height of a light or sound wave. It determines brightness in vision and loudness in hearing. THE EYE Pupil: Adjustable opening in the center of the eye through which light passes. Iris: A ring of muscle tissue that forms the colored part of the eye. It controls the size of the pupil Lens: The transparent structure behind the pupil that changes shape (called accommodation) to help focus images on the retina. Visual Acuity: The sharpness of vision. Nearsightedness: Can see nearby objects more clearly because distant object focus in front of the retina (eyeball may be too long). Farsightedness: Can see distant objects more clearly because nearby objects focus behind the retina (eyeball may be too short). Rods & Cones: The receptor cells for vision. Receptor cells are specialized neurons designed, in this case, to transduce light energy into neural impulses. Rods: detect black, white, & grey. Found mainly in the periphery of the retina. More than one rod connects to each bipolar cell. Thus, less light energy is necessary for them to cause the bipolar cells to fire. Necessary for NIGHT VISION & PERIPHERAL VISION. Cones: Found mainly in the center (fovea) of the retina. Necessary for COLOR VISION and VISUAL ACUITY. NEXT PAGE Unit 4: Sensation (cont.) VISION (cont.) Light waves stimulate rods & cones which synapse to bipolar cells, which synapse to ganglion cells. The axons of the ganglion cells come together to form the Optic nerves which transmit visual information to the brain. Blindspot: The area in the retina where the optic nerve leaves the back of eye. No rods or cones are located there, so no vision is possible at that location. Feature Detectors: Nerve cells in the brain that respond to specific features of a visual stimulus, such as shape, angle, or movement. Parallel Processing: The ability of the brain to process several aspect of a situation simultaneously. COLOR VISION Young-Helmholtz Trichromatic Theory: The theory that the retina contains three different types of cones-one most sensitive to red, one to blue, and one to green--which when stimulated in combination can produce any color. RED, GREEN, & BLUE are the PRIMARY COLORS OF LIGHT WAVES. Opponent Process Theory: Theory that opposing retinal processes (red-green, yellow-blue, & blackwhite) enable color vision. For example some cells are stimulated by red while inhibited by green; others are stimulated by yellow, while inhibited by blue. This helps explain afterimages. Color constancy: Perceiving familiar objects as having consistent color, even if changing illumination alters the wavelength reflected by the object. Middle Ear: Chamber between the eardrum and the oval window which contains the ossicles (three tiny bones--hammer, anvil, & stirrup) which concentrate the vibrations of the eardrum. Inner Ear: Contains the cochlea, semicircular canals, and vestibular sacs. Cochlea: a coiled, bony, fluid-filled tube through which sound waves trigger nerve impulses. Basilar Membrane: Membrane along the center of the cochlea that contains hair cells (the receptor cells for sound). Axons from the hair cells for the Auditory Nerves, which transmit neural impulses to the brain. PITCH PERCEPTION Place Theory: Theory that the pitch we hear is associated with the place where the basilar membrane is stimulated. Best for explaining high-pitched tones. Frequency Theory: Theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of the tone we are hearing. Best for explaining low-pitched tones. AUDITION Volley Principle: Helps explain in frequency Audition: The sense of hearing. theory how we can hear sounds with a frequency Frequency: The number of complete wavelengths in greater than 1000 cycles per second. While some a given period of time. Frequency determines pitch. neurons are "recharging" during the refractory period, Amplitude: Height of each wavelength--determines others are firing. loudness. Conduction Deafness: Caused by damage to the structures that conduct sound waves through the ear Sound Localization: Sound waves strike one ear (eardrum, ossicles). sooner and with more intensity than the other Nerve Deafness: Caused by damage to the cochlea's ear. With this information, the brain can determine the hair cells or the auditory nerve. NEXT location of the sound. PAGE Unit 4: Sensation (cont.) TOUCH Touch or tactile sense involves a mixture of at least 4 Molecules in the air reach millions of receptor cells in each nasal cavity. These cells send messages to the distinct skin senses--pressure, warmth, cold, and pain. Only pressure has identifiable sense receptors. COLD + PRESSURE = WETNESS COLD + WARMTH = HOT PAIN Gate-Control-Theory: Theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass. The gate is opened by stimulation of small nerve fibers and closed by stimulation of larger fiber or by information coming from the brain. TASTE Taste is the Gustatory Sense. Taste is a CHEMICAL SENSE and consists of the four basic tastes of sweet, sour, bitter, & salty. There may also be a 5th sense called "umami" or a meaty taste. olfactory bulb and the olfactory nerve which transmits the messages to the brain. BODY POSITION & MOVEMENT Kinesthesis: The system for sensing the position and movement of individual body parts. The receptor cells for kinesthesis are found in our muscles, tendons, & joints. Vestibular Sense: The system that monitors the head's (and thus the body's) position and movement. It is our sense of equilibrium. The semicircular canals and vestibular sacs in the inner ear contain receptors that tell us about our head's position. Each bump on the tongue contains over 200 taste buds. Each bud contains a pore that captures food molecules. The molecules cause hair-like neurons within the pores to fire. Taste Buds reproduce themselves every 2-3 weeks. Sensory Interaction: The principle that one sense may be influenced by another, as when the smell of food influences its taste. Check out HANDOUTS SMELL Smell is the Olfactory Sense. Smell is also a CHEMICAL SENSE. Very little is known about the olfactory sense. However, we are able to detect about 10,000 different odors. Smells are processed in the temporal lobes of the brain and in the LIMBIC SYSTEM, which may explain why certain smells seem to have an emotional component and can trigger memories. Unit 7: Perception Perception: The process of organizing and interpreting Monocular Cues: Distance cues that require the use of sensory information, enabling us to recognize one eye only. meaningful objects and events. 1. Relative Size: If we assume two objects are about the same size, the one that casts the smaller retinal image is perceived as being farther away. Perceptual Organization Figure-ground Relationship: Our ability to perceive any object (the figure) as distinct from its surroundings (the ground). Visual Capture: The tendency for vision to dominate the other senses when conflicting information is being received. Gestalt Organizational Principles: Gestalt psychologists emphasize our tendency to integrate individual pieces of information into a meaningful whole. To bring order and form to basic visual sensations, our brains follow certain rules for grouping stimuli together. 1. Proximity: We group nearby objects and belonging together. 2. Similarity: Figures similar to each other (i.e., as in shape or color) are groups together. 3. Continuity: We perceive smooth, continuous patterns rather than discontinuous ones. 4. Connectedness: When the are uniform and linked, we perceive spots, lines, or areas as single units. 5. Closure: We fill in gaps to create complete, whole objects. 2. Interposition (Overlap): If one object partially blocks another, the one that is partially blocked is perceived to be farther away. 3. Relative Clarity: Because light from distant objects must pass through more atmosphere, we perceive hazy object as being farther away than clear, distinct objects. 4. Texture Gradient: A gradual change from a coarse, distinct texture to a fine, indistinct texture signals increasing distance. 5. Relative Height: We perceive objects higher in our visual field as being further away. 6. Linear Perspective: Parallel lines (such as railroad tracks) appear further away as they converge in the distance. 7. Light & Shadow (relative brightness): Nearby objects reflect more light. Thus, given two identical objects, the dimmer one seems further away. 8. Relative Motion (motion parallax): If while riding in a train you fix your gaze on some object (the fixation point), objects closer than the fixation point appear to be moving backward. The nearer an object is the faster it seems to move. Objects behind the fixation point appear to be moving with you: The farther away Depth Perception the object is from the fixation point, the more slowly it Visual Cliff: A laboratory device for testing depth perception in infants. Even when coaxed, infants are appears to move. Motion Perception reluctant to venture onto the glass over the cliff. Binocular Cues: Depth cues that depend on the use of One way we perceive motion is by knowing that if an object keeps getting bigger, it is probably moving both of our eyes. towards us. If an object is shrinking, it is moving away 1. Retinal Disparity: By comparing the two from us. slightly different images received on each retina, the Phi Phenomenon: When two or more adjacent brain computes the distance of what we are looking at. The greater the disparity (difference) between the stationary lights blink on and off in quick succession, we perceive a single light moving. (Lighted signs use two images, the closer the object. this phenomenon). 2. Convergence: The extent to which the eyes Stroboscopic Movement: The brain will interpret a converge inward when looking at an object. The rapid series of slightly varying images as continuous greater the convergence, the closer the object. movement. By flashing 24 still pictures each second, a motion picture creates perceived movement. Unit 7: Perception (cont.) Perceptual Constancies Perceiving objects as unchanging (having constant lightness, color, shape, and size) even when our retinal images of them change. For example: Shape Constancy: We perceive the form of familiar objects as constant even when our retinal images of them Similarly, Blakemore & Cooper found that kittens whose vision was restricted to only seeing vertical lines during a critical period of development, later could not see horizontal lines. Perceptual Adaptation: In vision, the ability to adjust to an artificially displaced or even inverted change. Size Constancy: We perceive familiar objects to maintain a constant size even when their distance from us changes. Lightness Constancy: We perceive an object as having a constant lightness even when its illumination varies. Some Visual Illusions visual field. Perceptual Set: A mental predisposition to perceive one thing and not another (e.g., seeing the Lock Ness Monster instead of a piece of driftwood because of your beliefs). Context Effects: Any given stimulus may trigger radically different perceptions depending on the surrounding environment or circumstances. Culture may have a great impact on context and perception. The Ponzo Illusion (in two forms) Human Factors Psychology: A branch of psychology that explores how people and machines interact and how machines and physical environments can be adapted to human behaviors. The Ames Room Extrasensory Perception (ESP) The controversial claim that perception can occur apart from sensory input. Telepathy: Mind to mind communication Clairvoyance: The sensing of remote events that are presently occuring. Precognition: The sensing of future events. Telekinesis (psychokinesis): Ability to affect objects with the power of the mind. Parapsychologists: Psychologists who study paranormal occurrences, including claims of ESP. Muller-Lyer Illusion See HANDOUTS **Please see your textbook for explanations of these illusions. Sensory Deprivation People blind from birth, who later have their vision restored, can distinguish figure-ground relationships, can sense colors, but have great difficulty recognizing objects that they were familiar with by touch. Unit 5: Consciousness Consciousness: Our awareness of ourselves and our environment. Biological Rhythms: Periodic physiological fluctuations. 4. Evolutionary view: Sleeping when it was dark kept us safe. DREAM THEORIES Freudian Theory: Dreams help disguise unconscious Circadian Rhythm: The biological clock. It involves regular body rhythms (ex: temperature & sleep) that occur on a 24-hour cycle. STAGES OF SLEEP Stage 1: Alpha waves; hypnogogic hallucinations; sleep talking; hypnic jerk; slow down of biological functions (e.g., blood pressure, heart rate, respiration) & a decrease in temperature. Stage 2: Waves are slower (see some theta waves); sleep spindles; K-complexes; sleep talking; biological functions continue to slow. Stage 3: Transition stage. See first signs of delta waves; biological functions continue to slow. Stage 4: Deep sleep. All delta waves; bedwetting & sleep walking most likely. Biological functions are at there lowest. conflicts and motives. Manifest Content: According to Freud, the remembered storyline of a dream. Latent Content: According to Freud, the underlying "meaning" of a dream. Activation-synthesis Theory: Dreams spring from the mind's relentless effort to make sense of random visual bursts of electrical activity which originate in the brainstem and are given their emotional tone as they pass through the limbic system. Memory Consolidation Theory: The parts of the brain active when we learn something are similarly active later when we sleep and dream. Brain-Stimulation Theory: Periodic stimulation during dreaming helps form neural connections. Especially important in infants. After stage 4, the sleeper moves back to stages 3, stage 2, & then into REM sleep. REM Sleep: Rapid eye movement; dreaming; erections in males; paralysis. Also called "paradoxical sleep" because while the person is totally asleep, there biological function and brain waves appear more like a person who is awake. A full sleep-cycle takes about 90 minutes. As the cycles continue throughout the night, stage 4 sleep gets shorter and REM sleep gets longer. SLEEP THEORIES 1. Possibly certain chemicals depleted during the day are restored during sleep. 2. A build-up of "s-factor" during the day causes sleep at night. 3. Pituitary gland more active during deep sleep. So, sleep may be involved in growth process. (Babies and young people spend more time in deep sleep than older people). Regardless, if we don't get enough REM sleep, we will go into REM Rebound: The tendency for REM sleep to increase following a period of REM deprivation. SLEEP DISORDERS Insomnia: Recurring problems in falling or staying asleep. Narcolepsy: Disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep at inopportune time. Sleep Apnea: Disorder characterized by temporary cessation of breathing during sleep and momentary awakenings throughout the night. Night Terror: Disorder characterized by high arousal and an appearance of being terrified. Unlike nightmares, these occur during stage 4 sleep and are typically not remembered. NEXT PAGE Unit 5: Consciousness (cont.) HYPNOSIS Hypnosis: A social interaction in which one person (the hypnotist) suggests to another person (the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur. Posthypnotic Amnesia: Supposed inability to recall what one experienced during hypnosis; induced by the hypnotist's suggestion. Posthypnotic Suggestion: A suggestion, made during hypnosis, to be carried out after the subject is no longer Physical Dependence: A physiological need for a drug, marked by unpleasant withdrawal symptoms when the drug is discontinued. Psychological Dependence: A psychological need to use a drug, such as to relieve negative emotions. Psychoactive Drugs Depressants: Drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions. Barbiturates: drugs that depress the activity of the hypnotized; used by some clinicians to control undesired symptoms and behaviors (e.g., eat less, quit smoking, feel less anxiety, etc.). Hypnosis does not improve memory. In fact, it is likely to contaminate our memories. It is, however, useful in relieving PAIN. Possibly due to dissociation or a "split in consciousness". While part of the person is still aware of the pain, the conscious part of the person is not. Theories of Hypnosis 1. Divided Consciousness Theory: Suggests that dissociation occurs during hypnosis. A "split" in consciousness occurs. "Part" of the person is unaware of what is occurring, but another "part" is aware. This part is called: The Hidden Observer: Hilgard's term describing a hypnotized person's awareness of experiences, such as pain, that seem to go unreported during hypnosis. 2. Social Influence Theory: The subject simply becomes caught up in the "role" of being a hypnotized person. It involves role-playing, conformity, and obedience. DRUGS AND CONSCIOUSNESS Psychoactive Drug: A chemical substance that alters perceptions and mood. Tolerance: The diminishing effect with regular use of the same dose of a drug; requiring the user to take larger and larger doses in order to obtain the same effect. Withdrawal: The discomfort and distress that follow discontinuing the use of an addictive drug. CNS, reducing anxiety but impairing memory and judgment. Opiates: Opium and its derivatives (such as morphine and heroin); they depress neural activity, temporarily lessening pain and anxiety. Stimulants: Drugs (such as caffeine, nicotine, and the more powerful amphetamines and cocaine) that excite neural activity and speed up body functions. Amphetamines: Drugs that stimulate neural activity, causing speeded-up body functions and associated energy and mood changes. Ecstasy (MDMA): A synthetic stimulant and mild hallucinogen. It produces short-term euphoria. However, it harms serotonin-producing neurons causing long-term changes in mood and cognitions. Hallucinogens: Psychedelic ("mind-altering") drugs, such as LSD and marijuana, that distort perceptions and may evoke sensory images in the absence of sensory input (i.e., hallucinations). THC: The major active ingredient in marijuana. NEAR-DEATH EXPERIENCES Near-death Experience: An altered state of consciousness reported after a close brush with death (such as after a cardiac arrest); often similar to druginduced hallucinations. Monism: The belief that mind and body are different aspects of the same thing (when the body dies, so does the mind. Dualism: The belief that mind and body are two distinct entities (when the body dies, the mind may continue to exist). See HANDOUTS