Psych 230 EXAM 1 Study Guide PDF

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Study Guide for Exam 1...

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Quizlet unit 1 https://quizlet.com/_6zbihq Quizlet unit 2 https://quizlet.com/_6zbb7x Quizlet unit 3 https://quizlet.com/_6ztm1g Quizlet unit 4 https://quizlet.com/_70xadx Unit 1 – What is perception ● Are there really five senses? ○ There are 12 senses

● What is sensation? ○ Is the activation of sensory receptors due to a stimulus in the environment that results in the transduction of the physical stimulus into a neural signal, which allows for the brain/mind to interpret it. ■ An example of this is a song playing on the radio (stimulus), which then causes activation of auditory receptors which create a series of electrochemical ○ The registration of a physical stimulus in sensory receptors ■ It changes physical stimuli into info in our nervous systems (neural signals) ● What is perception? ○ Basics: stimulus ---> sensation -----> perception ○ The process of creating conscious perceptual experience from sensory input

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■ Actually giving meaning to something ■ Changing sensory input into meaningful conscious experience ■ Perception is what guides us into action Neural transduction ○ receptors, transduction, and neural response ■ Receptors respond to different forms of energy/stimulus, once the stimulus falls in receptive field it starts responding ■ Taking physical stimulus and turning it into electrical What is phenomenology? ○ All the internal experiences you get from being in contact with the world ○ Is the internal experience that everyone has of the external world around them ■ Because everyone is unique in their own prior experiences, beliefs, and physiology, we all may have different experiences of the world around us Aristotle and the five senses ○ “You cannot trust our senses” ○ Aristotle Illusion: we are all subject to illusions ○ Motion aftereffect ■ Also known as Waterfall illusion ■ An aftereffect is a sensory experience that occurs after prolonged sensory exposure to one stimulus that alters how we experience other stimuli after the prolonged exposure Thomas Young: ○ Light is a wave ○ colors are coded by three different kinds of nerve fibers Johannes Mueller: ○ doctrine of specific nerve energies ○ Each specific nerve has its own specific info it carries Von Helmholtz: ○ Constructionist approach ■ perception is constructed from both senses and cognitive processes ○ unconscious inference: brain plays a critical role in perceiving things but will play tricks on you, you perceive everything around you but your brain helps you a lot along the way ○ three basic color receptors (like Young) ○ Looked at giant squid Hering: colors are perceived through 2 pairs of opposing colors (four primary colors, not three) ○ Introduced idea against constructivism Weber’s Law: the just-noticeable difference between two stimuli is related to the magnitude or strength of the stimuli ○ Remember: JND ○ Ex: if she started review sesh earlier she would have to talk louder ○ Matters where you started

● Fechner: father of psychophysics, the study of the relation between physical stimuli and the perception they elicit. ○ Response compression ● Fechner’s law: sensation is a logarithmic function of physical intensity ● Gestalt psychology: The whole is larger than the sum of its parts ○ Example: Kanizsa Triangle ● Gestalt laws: ○ Law of Proximity: identical elements grouped together by proximity ○ Law of Common Fate: elements that move in an identical fashion are grouped together ■ Example: arrows moving up or down ○ Law of Closure: information is given by the closure of the element ○ Law of Similarity: if all the objects are exactly the same distance from one another but some are more similar to ones than others, the ones that are more similar will group together ○ Law of Good Continuation: our perceptual system always assumes good continuations ■ In nature most of the time things are flowing in a natural or good continuation ● Direct perception view: Same as gibsonian approach ○ All the information that you need to understand, like for example a vase of flowers in front of you, is given by the vase of flowers itself ○ The vase of flowers will project into your retina in such a way that is only consistent with that vase of flowers ○ You can directly experience that vase of flowers without having to do a bunch of extra computations ● Gibsonian approach ○ There is a particular type of motion to the image that is hitting your eye ■ When you approach an object it gets bigger in a lawful way ■ Can happen when you are in a car for example ■ Simple, observational approach, different stimulus in our environment has everything we need, we just need to perceive it ● Information Processing Approach ○ Borrow concepts from the computer in terms of maybe the mind can be understood as a computer ○ There must be some kind of central processing unit that does computations ○ Define the mind as a sequence of information processing stages to help you come to a decision ‘ ○ In conclusion: information flows through different boxes and each box is a particular stage ● Computational Approach ○ Additional components in which flow of information does not always go one direction ○ Many things done at the same time

○ Can do many computations at once ○ More complex and biologically plausible approach to understanding perception ● Neuroscience in Sensation and Perception (brain organization) ○ In 20th century we saw the emergence of neuroscience ● Methodologies in Neuroscience: ○ Microelectrode: technique that involves taking an animal and taking out a little part of their skull and use very little electrodes so we can implant them and study the neurons that we are interested in studying ○ Neuropsychology ■ Field of study ■ Visual Agnosia (inability to the process sensory information) ● People who get a brain lesion in temporal and occipital lobe, patients cannot recognize objects anymore ● Can point out features but not integrate into an object ■ Prosopagnosia ● The inability to perceive faces ● Cant put together faces only identify features ○ EX: big nose, flat nose, mouth w/ big lips ○ Electroencephalography (EEG) ■ Put a cap on a participants head with electrodes ■ Cannot localize where things are happening but understand very well the amount of time it takes ■ Cheaper ○ Functional MRI (fMRI) ■ Bold signal, oxygen level in brain, slow technique ■ Doesn’t tell you timing ■ Gives you spatial localization in where changes are happening in the brain

Unit 2 – Research Methodology ● What is a Psychophysical Scale ○ Something that can relate stimulus to psychological experience ○ Ex: Scolville scale of spiciness ■ Measures your experience of hotness ● Absolute Threshold ○ Minimum amount that you need to detect a stimulus ○ Ex: sense is vision and the threshold is a candle 30 miles away in a dark night ● Method of Limits (using crossover points) ○ Ascending series and descending series ○ Increase or decrease stimulus to detect a limit of something ○ Orderly component ● Method of Constant Stimuli (50% detection)

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○ Present the observer with a set of stimuli ■ A lot of trials ○ Random ○ Some above and some below the threshold ○ Produces S curve Method of Adjustment (observer adjusts) ○ Orderly like method of limits, but observer/participant controls changing the intensity ○ Ex: Watching TV, you turn up the volume to whatever you want ○ Find your threshold Sensitivity ○ Lower threshold= higher sensitivity ○ Low threshold means you are good at detecting stimuli ○ Sensitivity= ONLY strength of a signal ***Magnitude Estimation ○ Participants judge and assign numerical estimates to the perceived strength of a stimulus ○ ***Response compression: Curve starts fast but stops growing ■ Ex: Brightness, Fechner’s law ○ Response expansion: Starts slow and increases/grows fast ■ Ex: electric shock Steven’s Power Law ○ Stevens’ power law: P=cl^b ■ P= Perceived magnitutde of a stimulus ■ I= Intensity of the actual stimulus ■ c= constant ■ If exponent is below one you will get response compression ■ If exponent is above one you will get response expansion Catch Trials and Their Use ○ Problems of false reporting ○ Presenting nothing and still having them say if they detect a stimuli or not, if they do you know they are lying Signal Detection Theory ○ *****Criterion ■ You can make/set your criterion ■ You make a decision based on certain point in your head ■ Cut off that guides your responses(because of internal or external reasons) ● Something below it and something above it ○ d prime ○ Hit ■ Positive detection of the stimulus ○ Miss ■ Showed a stimulus and they did not see it

○ False Alarm ■ Falsely alarmed that something occurred ○ Correct Rejection ■ Correctly realized that there is nothing there ○ Receiver Operating Characteristic ● Changes in Criterion ● Differences in Sensitivity (d prime): Higher d prime= better at detecting stimulus ○ D prime tells you about the sensitivity ■ d=0 means no sensitivity ■ d=1 means moderate sensitivity ■ d=4 means high sensitivity

Unit 3 – Touch and Pain ● The sense of Touch includes a variety of sensations ○ Somatosensation: all the sensory signals from the body ● Touch receptors: ○ Thermoreceptors ■ Detects temperature ○ Mechanoreceptors ■ Detects mechanical displacements of skin ■ Sensory receptors that transduce physical movement on the skin into neural signals ○ Kinesthetic receptors ■ Detection of the location and position of your body parts through receptors in the muscles, tendons, and joints ■ Kinesthesis is part of a larger system called proprioception, that includes both kinesthetic and vestibular receptors ○ Nociceptors ■ Detects pain sensations ■ Found in dermis and epidermis ○ Itch receptors ■ Detects itch sensations ○ ****Pleasant/Gentle touch receptors ■ ????? ● The Skin and Its Receptors: ● Mechanoreceptors: Understand the 4 types of Mechanoreceptors ○ SAI: Detecting patterns, texture perception ■ Upper dermis ■ Small receptive field ■ Merkel cells ■ Ex: braille ○ SAII: Detecting stretching of the skin, are our fingers shaped properly to hold it?

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Larger receptive field Ruffini endings Low spatial resolution Dermis Stretch feedback ● When holding an object am I holding it the right way? ○ FAI: Respond to low frequency vibrations(detecting “slip”- adjust grip) ■ Small receptive field ■ Meissner corpuscles ■ High spatial resolution ■ Upper dermis ■ Medium sensitivity to temp variation ■ Perceiving change ● EX: Slipping ○ FAII: When objects make contact with our skin ■ Fly is on you, helps you feel the fly ■ Larger receptive field ■ Pacinian corpuscles ■ Low spatial resolution ■ Lower dermis ■ High sensitivity to temp variation What is proprioception: Perceiving limb position ○ Muscle spindles ■ Sense information about muscle length and muscle action ○ Joint receptors ■ Sense information regarding angle in our joints ○ Golgi tendon organs ■ Measure the force of a muscle’s contraction ○ alcohol consumption affects proprioception Pinocchio illusion ○ Applied a device to subjects that simulates vibrations and asked subjects to hold their nose while the device tells brain that arm is extending ■ Results in participant feel like their nose is growing outwards Patient: Ian Waterman ○ Lacked kinesthetic senses ○ In the dark he didn't know where his body is ○ Without peripheral feedback from kinesthetic receptors, his brain could not coordinate movements Definition of Pain ○ Unpleasant experience of actual or threatened tissue damage Nociceptive pain: pain resulting from tissue damage Other Types of Pain: ○ Neuropathic pain ○ Inflammatory pain ○ Empathy pain ○ Emotional pain

● Difference between A-delta fibers and C-fibers ○ A-delta fibers: Myelinated nociceptors responding to heat and pressure, faster ○ C-fibers: unmyelinated nociceptors responding to extreme heat, cold, pressure, and toxic chemicals, slower ● No Pain Sensation? Melzack and Wall (1988)’s study ○ People who do not experience pain tend to live very short lives ● What are the Two Pain Pathways to the Brain ○ Gate control works for the spinal pathway but not the other one ○ (1) Spinothalamatic pathway and (2) dorsal-column medial lemniscal pathway ● Somatosensory Cortex: area at the front of the parietal lobes that registers and processes body touch and movement sensations ● Somatotopic map ○ Organization of the primary somatosensory cortex maintaining a representation of the arrangement of the body. ● ***The Homunculus: A drawing of a human in which the proportions of the body parts has on the somatotopic map ○ Illustrates how many neurons represent the different body parts in the somatosensory cortex ○ Characteristics: ■ Somatotopy: even though there are some discontinuities(ie: hand next to face) ■ Distortions: Some body parts are overrepresented(ie: face, hands, genitals) ● Phantom limb syndrome ○ Some amputees feel their missing limb ○ The area responding to the limb has been taken over and processes other regions of our bodies ○ Helpful to adjust to life with a prosthetic ● ***Suborganization of the Somatosensory Cortex: ○ Area 1, 2, 3A, and 3B are all part of S1 ○ Area 1 receives input from mechanoreceptors and is therefore the primary area for tactile perception ○ Area 2 receives input from proprioceptors in the muscle and tendons(as doesArea 3A) ○ Area 3A receives input from nociceptors ○ Area 3B receives input from nociceptors, along with input from the mechanoreceptors ○ These areas then send information to S2(the secondary somatosensory cortex), which is the somatosensory system’s “what” channel for identifying the nature of the touched object ○ The “what” channel ■ S1 to S2, what we are interacting with ■ sometimes called the ventral system, is critical for using touch info to identify both the shape of an object and the identity of that

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object ■ This area allows us to discriminate softballs from grapefruits ○ The “Where” Channel: Correcting Grip ■ S1 to parietal cortex to frontal lobe ■ Also called dorsal system in the somatosensory system. The dorsal system allows us to control guided movements based on input from the somatosensory system. ● Ex: We use feedback from this system to adjust our grip on a large textbook when it starts slipping away from our hands. ● Ex: When we feel barbell is too heavy, feedback from the somatosensory system tightens our grip Pathways of pain: ○ Gate Control Theory: When downward signals are excitatory, the transmission of pain info is block or inhibited. ○ Implications of Gate Control Theory: If you are prisoner being tortured your fear opens the gate wide open, thus a small prick will cause a lot pain. On the other hand, if you are at dentist you are not expecting pain so even if there is pain our gate control mechanism mutes the pain. ○ Over-sensitization vs. desensitization Role of Anterior cingulate cortex (ACC) in pain perception: ACC receives input from the primary and secondary somatosensory cortices(S1 and S2), and responds to pain caused by pinches, pricks, and extreme heat and cold. ○ ACC is an area important to the emotional component of pain perception(activity in ACC when others are experiencing pain) ○ It can regulate pain and likely can initiate the gate control mechanism to inhibit pain ****Role of Prefrontal cortex in pain perception Empathy Pain The Neurochemistry of Pain: Endogenous Opioids: Neurotransmitters produced by the body that reduce pain via analgesia throughout the body/ ○ Analgesia: Processes that act to reduce pain perception ○ Runner’s high ○ Other chemicals - Addiction risk

● The Perception of Itch: Pruriceptors: Receptors in our skin that respond to mild irritants by producing itch sensations ○ Proprioceptors respond mostly to chemical irritants on skin rather than tissue damage ● Gentle Touch ○ Mechanisms of pleasant touch ○ brain regions related to the pleasant touch ● Haptic Perception: The active use of touch to identify objects ● Active vs. Passive Exploration ○ Active exploration: We experience object constancy

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○ Passive exploration: We feel the point of contact of the object, not one object ○ Experiment by Klatzky, Lederman, & Metzger (1985) Tactile agnosia: Inability to identify objects by touch ○ Ability to identify textures, shapes, and other characteristics might be preserved Touch Psychophysics Sensitivity to pressure ○ Weinstein (1968)’s experiment: He used nylon monofilaments ■ Detection threshold varies greatly as a function of the location tested on the body ***A Model of the Body’s Two-point Threshold Response ○ Two point threshold ***How we accurately perceive point localization How we can detect Irregularities on surfaces ○ Very high sensitivity as we can detect irregularities of just .85 microns Similarity between touch and vision ○ Visual acuity: Determined by the spacing of the cones on the retina ○ Tactile acuity: Determined by the spacing between the different tactile units in the skin Masking: What happens when different stimuli are presented at the same location over time? ○ Results of masking: DONT NEED TO KNOW THAT WELL(just to get a little knowledge going into vision, know basics of masking tho) ■ Recognition is impaired(interference) ■ Backward masking (ex: target pattern followed by mask) is more interfering than forward masking(ex: the mask preceded the target) ■ Meta-contrast masking: Target and 50ms later a mask that doesn’t overlap in space nor time Disorders and phenomena related to touch ○ Diabetic foot ■ People with diabetes have nerve damage which causes low sensitivity in their lower limbs like legs and feet ■ The blood does not reach those areas of the body very well which also causes low sensitivity in the feet ■ Consequences: if you have a blister or small cut and do not notice it can cause an ulcer or a very bad infection ○ Numb sense ■ Subcortical stroke along the somatosensory pathway ■ Complete loss of all somatosensory processing on the left ○ Anarchic hand: Complex goal-directed movements of a hand that are performed against the patient’s will ■ Cannot be inhibited ■ Caused by lesions in the anterior part of the corpus callosum ■ Patient GP: “her left hand would take some fish bones from leftovers and put them into her mouth..”

○ Alien hand ■ Hemiasomatognosia: Loss of the sense of one’s own body ● Description of Brion and Jedynak, 1972: “the patient who holds his hands one within the other behind his back does not recognize the left hand as his own…” ○ Out of body experience ■ 1.The feeling of being outside of one's body ■ 2. An elevated visual spatial perspective ● Feeling 2-3 meters away from the body ○ Rubber hand illusion ■ Unit 4 – Chemical Senses ● The Anatomy and Physiology of the Olfactory System ● ****The Nose: DONT HAVE TO KNOW DIFFERENCES ○ ***Nasal septum ■ ○ Turbinates ■ Ridges inside of nose that bring molecules upwards.. ○ Olfactory cleft ■ Retina of the nose ○ Olfactory epithelium ■ Contains olfactory receptors ● Anosmia ○ Lose your sense of smell ■ (there are many ways you can lose your sense of smell) ● ***The Anatomy of the Olfactory Epithelium ○ The glomeruli pull together the information from identical olfactory receptor neurons (green, blue, red) ○ Generates pattern of activity of different odorants, glumori creates odorant map: Odorants with similar structure are going to be coded by the map nearby ○ Glomeruli are in olfactory bulb ○ Sensation of smell comes from the response all across glomeruli (how much green…) ● ***Olfactory Pathway ○ Piriform cortex: in temporal lobe ○ Memory and emotion areas ○ Orbitofrontal ■ Negative or positive smell? ● Macrosomatic vs Microsomatic species: Olfaction-Vision Tradeoff ○ Macrosomatic species: Species that depend heavily on smell ■ Pigs, salmon, bear ○ Microsomatic species: Species that depend more on vision and audition ■ Human

● ***The Anatomy of the Trigeminal Nerve ○ Trigeminal Nerve: A nerve that is associated with the feel of odorants; also known as the fifth cranial ne...