Psych 100 SG 2 - Professor: Jeff Henriquez PDF

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Professor: Jeff Henriquez...

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How do we construct a view of the outside world? 1) Detect physical energy from the environment, 2) Physical energy is encoded as neural signals, and 3) Information is selected, organized, and interpreted Psychophysics the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them Absolute threshold the minimum stimulation needed to detect a particular stimulus 50 percent of the time Subliminal stimuli stimuli that are below the level of conscious awareness (typically a hoax) Difference threshold the minimum difference between two stimuli required for detection 50 percent of the time Weber's Law the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount) Sensory adaptation diminished sensitivity to an unchanging stimuli (ex. Febreeze "you've gone nose-blind"); allows us to pick up important environmental changes How do we see? 1) Light enters through the cornea and passes through the pupil (iris controls how big the pupil is) 2) Light passes through the lens and focuses rays onto the retina 3) Signals are sent through the optic nerve Rods retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond Cones retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations. Amplitude Determines brightness in light waves and loudness in sound waves Wavelength

Determines color in light waves and pitch in sound waves

Upgrade to remove ads Only $2.99/month Young-Helmholtz Trichromatic Theory the theory that the retina contains three different color receptors—one most sensitive to red, one to green, one to blue—which, when stimulated in combination, can produce the perception of any color Hering Opponent Process Theory theory that there's a red/green, yellow/blue, dark/light receptors Dual Process Theory Combines two previous theories about color into one; three color cones, but each signal is then sent to the corresponding opponent-process cell How does sound travel through the ear? 1. Soundwaves are collected through the outer ear (pinna) 2. It moves down the auditory canal into the eardrum which causes it to vibrate 3. The vibrations then cause the ossicles to vibrate as well 4. Motion in the middle ear causes the fluid to flow. This causes tiny hairs in the cochlea to move. 5. The motion of the hair is converted to electric impulses which are transported to the hearing nerve and transmitted to the brain Four sensations of touch pressure, warmth, cold, pain Touch receptors Thermal receptors and pain receptors Nociceptors pain receptors (detect harmful temperatures, chemicals, pressure, etc.) Sense of smell chemical sensation; provides important info that aids in decision making Perception active/creative process in which raw sensory data are organized and given meaning Gestalt Principles of Perceptual Organization -we have the tendency to integrate pieces of information into meaningful wholes -the wholes we perceive are often more than the sum of their parts

Upgrade to remove ads Only $2.99/month Figure-Ground Relations local stimulus is seen as a figure against a background of other stimulus Law of Similarity tendency to group together figures that are similar to each other Law of Proximity elements that are near each other are likely to be perceived as part of the same configuration Law of Closure the tendency to fill in gaps to create a complete image Law of Continuity tendency to link individual elements together so that they form a continuous line or pattern that makes sense Depth perception the ability to perceive the world in three dimensions Binocular cues depth cues, such as retinal disparity, that depend on the use of two eyes Retinal disparity a binocular cue for perceiving depth by comparing images from the retinas in the two eyes, the brain computes distance—the greater the disparity (difference) between the two images, the closer the object. Convergence A binocular cue for perceiving depth; the extent to which the eyes converge inward when looking at an object Monocular cues depth cues, such as interposition and linear perspective, available to either eye alone

Upgrade to remove ads Only $2.99/month Relative size a monocular cue for perceiving depth; the smaller retinal image is farther away

Interposition monocular visual cue in which two objects are in the same line of vision and one partially conceals the other, indicating that the first object concealed is further away Relative height a monocular cue for perceiving depth; objects higher in our field of vision are perceived as farther away Linear perspective A monocular cue for perceiving depth; the more parallel lines converge, the greater their perceived distance. Relative motion As we move, objects that are actually stable may appear to move Light and shadow Nearby objects reflect more light to eyes. Given two identical objects, the dimmer one seems farther away What is Learning? a relatively permanent change in an organism's behavior due to experience (Note: a child walking is not learning) Classical Conditioning simple learning that does not require cognitive thinking; an organism learns to associate stimuli and anticipate certain events Unconditioned Stimulus (US) stimuli that automatically triggers a response (don't need to learn to react to it Unconditioned Response (UR) unlearned, naturally occurring response to the unconditioned stimulus (US), such as salivation when food is in the mouth. Conditioned Stimulus (CS) a stimulus that elicits a response only after learning has taken place (ringing a bell when bringing food, the bell is the CS) Conditioned Response (CR) learned response to a previously neutral (but now conditioned) stimulus (CS) Neutral Stimulus (NS) a stimulus that elicits no response before conditioning

Acquisition CS is paired with US, and then CS comes to elicit CR. Phase length varies Extinction US no longer follows CS, and CR eventually disappears Spontaneous Recovery If CS is presented to a subject after a period of rest and CR reappears Generalization Tendency to respond to stimuli resembling CS Discrimination Responding only occurs in response to one specific stimulus Ivan Pavlov discovered classical conditioning; trained dogs to salivate at the ringing of a bell Operant Conditioning Process whereby an organism learns to associate a response and its consequences and thus to repeat acts followed by rewards and to avoid acts followed by punishment; simple and does not require cognitive thinking Law of Effect If behavior leads to a good thing, then it is repeated; if behavior leads to a bad thing then it is not repeated (teaches consequences) Edward Thorndike First described operant conditioning when working with cats (solving puzzles to get out of a box like lifting a latch); saw slow decrease in time needed to solve but no insights on how to solve problem (discovered solution accidentally) B.F. Skinner Further studied operant conditioning (known for operant conditioning more than anyone else in psych) Skinner Box Used to observe operant conditioning; box contains different levers, buttons, etc. to teach animals cause-effect consequences (good or bad); has a way to deliver good or bad consequences; connected to computers Reinforcer Stimuli that increases the probability of a behavior

Primary reinforcer Events that are innately reinforcing (don't need to learn it) Secondary reinforcer Require learning (ex. You need to learn that money has value, so money is a secondary reinforcer) Positive reinforcement Increases the probability of subject behavior with desirable stimuli (ex. I'll give you free food if you attend this event) Negative reinforcement Increases the probability of subject behavior by taking away undesirable stimuli (ex. If you do your homework you don't have to do the dishes) Punishers Stimuli that decrease the probability of behavior Positive punishment Presentation of an averse stimulus to decrease behavior (ex. Smacking a child's hand at the store when they touch everything) Negative punishment Taking away desirable thing to decrease behavior (ex. grounding) Shaping Method of successive approximations; reward responses that are ever-closer to that desired behavior while ignoring all other behavior/responses (ex. Training a dog to open a cabinet by using treats) Observational Learning learning by observing others Modeling the process of observing and imitating a specific behavior; modify a behavior to fit yourself Albert Bandura researcher famous for work in observational or social learning including the famous Bobo doll experiment Bobo Doll Experiment nursery school students observed an adult play aggressively (yelling & hitting) with an inflatable clown (Bobo); when children were later allowed to play with the Bobo, those children who

witnesses the Bobo doll performed the same aggressive actions and improvised new ways of playing aggressively How do we decide to social learn? 1.) Outcome (how did that behavior end up for that person?) 2.) How similar am I to the model? 3.) Status of the model (is the model a loser?) When do we start imitating? 1.Facial expressions can be imitated by infants as young as 2 or 3 weeks old. 2. 9 month old infants can imitate a novel play behaviour. 3. 14 month olds can imitate acts modeled on television. Prosocial behavior Watching others model good behavior increases viewer's tendency to help others Memory the persistence of learning over time through the encoding, storage, and retrieval of information Information processing model model of memory that assumes the processing of information for memory storage is similar to the way a computer processes memory Encoding the processing of information into the memory system—for example, by extracting meaning. Automatic encoding Encoding requires no effort; Semantic (meaning of words) and Visual (encoding of picture images) Effortful encoding Effort to encode and remember information is required (i.e. exam information) Herman Ebbinghaus (1850-1909) Tested himself to learn about memory; wanted definite answer to how much he could remember and how long it took; found more information requires more repetitions and more time lessens retrieval (ex. five years later) but it takes less time to re-learn Savings When time passes after learning information, it takes less time to re-learn that information than it took to originally learn it Nonsense syllables 3 letters that do not make words combined into a list; Ebbinghaus made a list of "words" from them, memorized them and kept track of how long it took

Spacing Effect Breaking study sessions down into smaller session helps improve memory; has to do with attention span; more likely to encounter interference (interruptions) in long sessions Overlearning Continued rehearsal of material after one first appears to have mastered it; allows for bigger savings; no such thing as learning something too much (you can always benefit from this) Semantic Encoding Relating the meaning to an example Visual Encoding Mental pictures Chunking Organizing information into manageable sections for easier memorizing Storage the process of retaining encoded information over time Stage model Human memory system has three stages/types of memory information must pass (Atkinson and Shiffrin '68) Problems with stage model 1.) Some information can go straight to long-term memory without conscious awareness 2.) Working memory vs. short-term memory Working memory Associates new and old information to solve problems, and information that we focus attention on Sensory Memory First stage of information processing; sensory receptors are stimulated by external energy; short term periods Iconic sensory memory Visual stimuli (brief) Echoic sensory memory Auditory stimuli (little longer than visual) Short-Term Memory

Temporary but longer than sensory memory; limited storage capacity (around 7 chunks); if rehearsal is used, memory lasts longer George Miller (1956) Discovered Magical Number Seven: People can store about seven chunks of information (give or take two) Digit Span Test memory test in which a series of numbers is read to subjects in the experiment who are then asked to recall the numbers in order Long-Term Memory (LTM) With enough repetition, memories are stored for longer; can be permanent/semi-permanent storage; no known capacity Episodic memory (LTM); events (concerts, etc.) Procedural memory (LTM); how to do things (ride a bike, etc.) Semantic memory (LTM); factual information (test information, etc.) HM Had entire hippocampus removed; unable to form long-term memories (exotic) AJ Remembers every detail of her life since she was fourteen Retrieval the process of getting information out of memory storage Recall Retrieve information learned at some point with no help (ex. Short answer questions/essay questions) Recognition Measure of memory where a person must identify items (ex. Multiple choice test) False positives Error of recognition where people think they recognize some stimulus that is not actually in their memory (i.e. seven dwarves example)

Retrieval cue A stimulus for remembering; usually out of our control Forgetting Discard information not needed; mostly sensory memory; short-term discarded when no longer important; long-term can become distorted; anything goes wrong at any stage can lead to this Encoding failures Some information never enters long-term memory Storage decay fading of the physical memory trace Retrieval failures Difficulty retrieving previously stored information Proactive interference Prior learning interferes with recall of new information (i.e. trying to learn something new but only remembering old things); Retroactive interference New learning interferes with the recall of old information (i.e. learning something new and then not being able to recall the old thing) Childhood amnesia Inability to retrieve many memories (exotic) before age 5; this is normal for most people Amnesia Not normal; severe deficit in remembering events caused by problem(s) in the brain; i.e. Alzheimer's, traumatic brain injury Location: Short-term memories Prefrontal cortex and temporal lobe Location: semantic memories Frontal lobe Location: Episodic memories Temporal lobe Location: Procedural memories Cerebellum Location: Formation of new semantic and episodic memories

Hippocampus...