PSY 200 Exam I Study Guide
PSY 200 Exam I Study Guide PSY 200
Popular in Cognitive Psychology
Popular in Psychlogy
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
This 12 page Study Guide was uploaded by Kathryn Chaffee on Thursday February 4, 2016. The Study Guide belongs to PSY 200 at Purdue University taught by Gregory Francis in Fall 2015. Since its upload, it has received 21 views. For similar materials see Cognitive Psychology in Psychlogy at Purdue University.
Reviews for PSY 200 Exam I Study Guide
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/04/16
Fall 2015 PSY 200 Fore-brain Hind-brain Cortex Brain stem Similar to two thick, Hypothalamus (appetite, crumpled newspapers thirst, temperature, Grooves (fissures or sulci) hormones) separate regions Thalamus (sensory gateway, except smell) Limbic lobe (sexual behavior, emotional behavior, memory) Cerebellum (muscle control, learning) STUDY GUIDE #1 Lecture 2 Contralateral processing refers to the processing in the brain being done on the opposite side of your organs. For example, control of your right arm is from the left side of your brain and information from your left field of view goes to the right side of your brain. Information from your left field of view travels to the right side of your brain. Your left field of view is all the information from the middle to the left, and your right field of view is all the information from the middle to the right. The left field of view is not completely from our left eye, and vice versa. Information from the left field of view (some from the left eye and some from the right eye) goes to the right hemisphere. There is a binocular visual field that is the overlap of the two visual fields. If you cut the corpus callosum, the transmission of information between the two hemispheres is altered. The left hemisphere is the dominant hemisphere for language and speech. When the word shows up to the right of the fixation point in the right field of view, the information travels to the left hemisphere, and the subject is able to repeat what they saw. However, if the object is shown to the left of the fixation point in the left field of view, the information travels to the right hemisphere, and the subject is unable to say what he or she saw. When the subject is asked to draw what they saw, they are able to draw a picture of what they saw with their left hand. The information is in the right hemisphere, and is able to control the left hand. In CogLab, we tried to see if we could measure the differences between our hemispheres. In the lab, we stared at a central fixation point, while a word was presented to either the left side or the right side of fixation. Our task was to judge whether the presented word was “old” (seen in an earlier trial) or “new” (not previously seen in this experiment). Federmeier & Benjamin found that there was better memory Fall 2015 PSY 200 performance for words presented in the right visual field, because words in the right visual field go to the left hemisphere, which is known to be specialized for language. There are other explanations: reading goes from left to right, from fixation to right visual field, there’s a perceptual advantage to the right visual field, and an attentional advantage to the right visual field. It is difficult to come up with an experiment that isolates hemispheric specialization. It was hypothesized that left-handed people would have different data than right-handed people. Researchers thought that left-handed people would have more success using their right hemisphere, and right- handed people would be better at using their left hemisphere. Limbic lobe Sexual behavior Emotional behavior Memory Occipital lobe Receives information from the eye Most investigated area of the brain Parietal lobe Sensations of pain, temperature, touch, and pressure Primary sensory area is located in this lobe Sensitivity involves disproportionate areas of the brain, relative to the size of the body part Temporal lobe Hearing Speech (left) Music (right) Memory and attention Visual recognition Frontal lobe Largest part of cortex Planning Fall 2015 PSY 200 Prediction Motor area Speech area In the primary sensory area, it is sensitive to touch on different parts of your body. Locations that are next to each other on the body are close to each other in the brain. For example, sensory area for the teeth, gums, and jaw are close to the sensory area for the tongue. The sensitivity of a body part indicates how much of the brain is dedicated to that region. For example, the lips have a larger region in the brain so they are more sensitive. Brodman’s areas: different regions of the brain that look different than another part of the brain. The differences in the areas do different functions. Giving the areas different names helps people understand what area people are talking about. Lecture 3 Good temporal resolution means that it responds in real time to information that changes in time and to the cognitive process that happens in real time. The measurement is the electrical signal on the scalp, and it changes as we are exposed to different stimuli in our environment. Good temporal resolution means that it is able to record the brain activity as it occurs and changes. Poor spatial resolution is due to the fact that we never really know which part of the brain is making the electrical current. The signal located at a particular location could come from many different places in the brain. Temporal resolution helps us determine when something happened. Spatial resolution tells us which place is active in the brain. Poor temporal resolution means that we are unable to pinpoint when an electrical signal occurs. Poor spatial resolution means that we are unable to pinpoint where the electrical signal is coming from. EEG: good temporal resolution, poor spatial resolution Fall 2015 PSY 200 There is good temporal resolution because it shows the electrical impulses as they are occurring in time There is poor spatial resolution because it is unknown where exactly that impulse is coming from fMRI: pretty good temporal resolution, very good spatial resolution It has pretty good temporal resolution because it gives the electrical impulses as they are occurring in seconds It has very good spatial resolution because it measures the BOLD (blood oxygen level dependent) percent changes in order to determine where the more active neurons are. EEG brain scans measure the electrical activity in the brain by connecting electrodes to the scalp. Magnetic Resonance Imaging (MRI) involves a magnetic field that forces the protons in your body to line up. Pulses of radio entering the field cause protons to bounce around, and they emit a signal upon returning to their normal position. The signal they produce can be decoded in a map. The MRI provides a map of a slice of the brain at a time, thus it takes multiple slices of the brain to build a full image. The MRI machine is similar to an X-ray except that it can look at soft tissue, such as the brain. It is often used to gather information about any anatomical differences between brains. MRIs allows for the early detection of brain disease, tumors, ect. MRI scans has great spatial resolution but it only shows structure, and there is no way to know what a brain area does. Functional MRIs (fMRI) differentiates between active and inactive neurons, which is shown by the concentration of oxygen. The measurement is called the “blood oxygen level dependent” (BOLD), and it roughly tracks the flow of blood in the brain. This is because more active neurons recruit more blood. fMRI has very good spatial resolution and pretty good temporal resolution. In order to analyze the fMRI scan, we look for differences in activity. To do this, we use the subtraction method, which means we subtract the fMRI signals produced by one condition from the fMRI scans produced from another condition. The difference map indicates those brain regions that are involved in different cognitive tasks. The difference map is usually what is reported. Colors mark places in the brain that are statistically different between conditions. A common misconception in the popular press is that brain scans demonstrate a physiological basis to things that were thought to be emotionally or cognitively based. For example, the press released the Fall 2015 PSY 200 information that the MRI scans of stutterers showed that there was a difference in the brain scans of those who stutter and those who don’t, and that stuttering was based on a physiological difference in the brain. However, this report is nothing new because all behavioral traits are physiologically based. Everything that makes us “us” is based on our brain. Difference maps are used to study cognition. To make a difference map, fMRI signals are recorded during two different cognitive tasks. Subtract the fMRI signals produced by one condition from the fMRI signals produced by another condition. The difference map indicates those brain regions that are involved in the different cognitive tasks. But, it does require a sophisticated statistical analysis in order to avoid false positives. To be able to determine which area of the brain is used for certain cognitive activities, a difference map is used. A difference map allows us to determine which brain regions are involved in each task. Colors mark places in the brain that are statistically different between cognitive activities. Once you subtract the scans for one cognitive task (seeing a blank screen) from the scans of another cognitive task (seeing a face on the screen), we can tell the difference in cognitive activity between the two tasks. It is important that you must contrast the right types of scans to ensure that there is enough difference in the scans to determine which area is focused on which cognitive task. Functional MRIs use the measurement called BOLD, which means “blood oxygen level dependent”. The concentration of oxygen is measured by BOLD. The BOLD signal tracks the flow of blood in the brain. The more active neurons recruit more blood. More active neurons recruit more blood. When an area of the brain becomes activated, it recruits more blood to that area. The blood flow through the brain is shown in fMRIs. The results are shown in a color map. The blue/green color in the map is shown to represent normal blood flow through the brain. The red/black areas in the map represent abnormal blood flow. Therefore, the red/black color represents the inactive neurons in the brain. Limitations of brain scanning: Does not really tell us how the brain works Instead, it tells us approximately where something occurs Sometimes, it can tell when something occurs Even finding where something occurs can be problematic Fall 2015 PSY 200 Lots of cognitive abilities involve many different areas of the brain Most of the time theories of cognition are derived from experimental psychology Brain studies are used to explore how to implement the theories Lecture 4 In order to determine the relationship between cognitive activity and brain activity, the difference between the cognitive events scans and the brain activity scans (control) is taken. This process helps determine which events are cognitive and which are basic brain events. The tongue display unit attempts to present spatial information for blind people. People can use a TDU to discriminate shapes. The TDU is a strip of plastic that is embedded with vibrators that are arranged in a graphical array and gives a command as to which positions should vibrate. As they vibrate in a certain pattern, the person can make out the shape given from the TDU. An fMRI conducted when someone is using the TDU shows that using the TDU involves areas of the motor cortex instead of the areas that are typically involved in visual perception. Hence, brain scans can tell us a lot of information about what areas of the brain are being used in certain cognitive tasks. There have been several attempts to read someone’s mind through brain scans. In the tests, subjects have been asked to add or subtract numbers and to select their choice at the end. Based on the choice at the end, we can deduce whether the subject chose addition or subtraction for the trial. By making an fMRI scan during the selection process, we can build a recognition system that distinguishes the brain patterns for addition and subtraction. A limitation of using an fMRI is that if a subject decides to multiply the numbers, a system trained to distinguish between subtraction and addition is clueless. In general, brain scans provide a very limited form of mind reading. Another research group analyzed fMRI responses to reproduce a shown image through thought reconstruction. They accomplished this by showing an image to the subject and scanning the back of the head. They take the scan and try to reproduce the image that must have been shown on the screen. Thought reproduction depends on where the signals come from. For example, there will be fewer errors for the “lower” brain areas where the image is being processed. These studies are mostly a demonstration of technology because we already know Fall 2015 PSY 200 the brain represents visual information. These kinds of studies tell us that the neurophysiological differences between cognitive events can be measured by these brain-scanning technologies; therefore, failure would only indicate limits of the technology. The limit of thought reconstruction is that as the number of possible images to be shown increases, it becomes harder to reconstruct the shown image. Difficulties with statistics in brain scans: So much data that it is difficult to know what to do with everything (statistical analysis is complicated!) Easy to do the statistics incorrectly Even with purely random noise, there will be statistically significant findings These problems can never be entirely eliminated Neuron anatomy: 1. Dendrite – branch out from the soma and control signal input 2. Soma – integrates the signal 3. Axon – carries the output signal down the neuron 4. Myelin sheath – insulates the axon Lecture 5 Action Potential: The electrical signal of a cell is established by the relative amount of charged ions inside versus the outside of the cell. At the resting level, the cell has a charge of -70mV. Inputs change the resting potential of the cell. An action potential occurs when a neuron sends information down the axon. Action potentials are caused when + the sodium channel opens and positively charged Na ions flow into the negatively charged inside of the cell. After the inside of the cell becomes positive, the potassium channels open and release potassium to the outside of the cell, essentially reversing the process. It is as this time that the sodium channels also close. The cell returns to the resting potential of -70mV after the potassium channels close. Excitatory: when our neuron sends an output, the receiving neuron is more likely to produce an action potential Inhibitory: when our neuron sends an output, the receiving neuron is less likely to produce an action potential Inhibitory cells are necessary in the brain to ensure that there are not too many action potentials firing at once. In epileptics, seizures are caused by too many action potentials occurring at one time and Fall 2015 PSY 200 because the excitatory cells activate everything until they exhaust themselves. Synapse: The information travels down the axon of one neuron and communicates with the dendrites of another neuron. There is a synaptic cleft between the axon of the sending neuron and the dendrites of the receiving neuron. The signal travels down the axon to the terminal where neurotransmitters become encased in a vesicle, travel to the edge of the axon, and are then released into the synaptic cleft. The neurotransmitter signals (ligand) binds with the receptors and opens the channels. The opening of the channel allows the ions to flow into the receiving cell and create an action potential. Molecules have a particular 3D shape. Different molecules have different shapes. Neurotransmitters are molecules, and each one has a different shape. There is a receptor for each neurotransmitter. Receptors act as a filter for the cell because they can only accept neurotransmitters that fit their specific shape; therefore, the binding of a neurotransmitter to its receptor is very specific. Tourette’s syndrome is caused when there is too much dopamine in the brain. Too much dopamine in the brain causes “tics”. Haldol is used to treat Tourette’s by blocking dopamine receptors in the brain. Parkinson’s disease is caused when there is a lack of dopamine in the brain. In extreme cases, the patients can become “frozen”. L-DOPA is used to treat Parkinson’s because it is a precursor of dopamine, which means it helps the body to start making dopamine on its own. It sometimes solves the problem but it also has a lot of side effects. Prozac is a selective serotonin reuptake inhibitor (SSRI). It keeps serotonin (neurotransmitter) bound to a receptor for longer than usual, thereby increasing its effect. Prozac is a reuptake drug, meaning that it knocks out enzymes that remove the neurotransmitter (serotonin) from the receptor, which gives the serotonin a bigger effect. LSD: resembles serotonin Curare: blocks acetylcholine – tells our muscles to contract, stops the muscles Enters the receptor but does not trigger reaction, partly closes the receptor protein so neurotransmitter cannot enter Cocaine: prolongs effects of dopamine (it’s a reuptake drug) Knocks out enzymes that remove the neurotransmitter from receptor, neurotransmitter has a bigger effect Fall 2015 PSY 200 Morphine: resembles a small set of neurotransmitters called endorphin peptides (modulate pain perception) Accepted by receptor and with a similar effect Lecture 6 The firing rate of the cell is the number of action potentials in a certain length of time. A single action potential has little effect, but a rapid series of action potentials can influence other cells. A receptive field is the set of stimuli that reliably changes a cell’s firing rate. A stimulus could excite the cell, resulting in an above normal firing rate, or it could inhibit the cell, resulting in a below normal firing rate. In the CogLab experiment, we identified and mapped our blind spot. When both eyes are open, the light that falls upon the blind spot in one of the eyes falls upon the non-blind spot in your other eye. Therefore, when both eyes are open you won’t have a blind spot. Also, our eyes automatically follow the dot instead of staring at the fixation point, which disrupts the results of the experiment. Why don’t we see the blind spot? The blind spot is often the peripheral, and the bigger receptive field makes it more difficult to make out the details. The blind spot is in the region where things are big and fuzzy. Also, we cannot be aware of information that we cannot detect. To test the presence of an inhibitory surround for the on-center, off- surround cells, we should add light to the surround and analyze the firing rate of the cell. If light is added to the surround, the response will decrease. If light is added to the cell and the response increases, then the light was added to the on-center region of the cell. The receptive field of the cell includes any place on the retina where light excites the cell and any place where light inhibits the cell. When light is added to the center region (on-center) of the cell only, the cell emits a strong response. When light is added to the surrounding region of the cell, it reduces the response. Light added to the surrounding region causes the neurons to release inhibitory signals, thereby reducing the response. Light added to the center region gives a good response. On-center, off-surround cells send action potentials to simple cells in parts of visual cortex, which have oriented receptive fields. Simple cells come in a variety of types, but all are sensitive to bars or edges of a Fall 2015 PSY 200 preferred orientation at a particular location. Simple cells have strong responses at edges. Receptive field hierarchy: the on-center, off-surround neurons respond to spots of light, combinations of these neurons feed into simple cells, which respond to bars or edges of light of different orientations at different positions, and they feed into more complicated cells, which may respond to curves or whole patterns. Receptive fields seem to get ever more complex. Receptive fields inherit some properties from “lower-level” cells, but they also gain new selectivity by interacting with each other (and across levels). Many simple cells feed into a complex cell, which is insensitive to direction of contrast and responds to an oriented bar in many different places. Often these cells are also sensitive to directions of motion. In the inferior temporal cortex of monkeys, some cells appear to have receptive fields that respond to monkey faces, in profile. Other cells appear to have receptive fields that respond to hands. It is unlikely that there is a single cell that exclusively responds to the presence of your grandmother’s face for two specific reasons. Firstly, there are not enough cells to be able to remember grandma in all the different contexts (Ie; grandma smiling, grandma frowning, grandma with her hand on her head, ect). Secondly, cell death occurs throughout our brain, but that doesn’t result in forgetting information. If this is the case, the cell death of the cell that responds to grandma’s face would result in us forgetting our grandma. Lecture 7 Resonance hypothesis: When we have a cognitive state, it corresponds to the resonance state of a stable pattern of activity across these networks. Some neurons are active and they stay active and some are inactive and stay inactive. Cognitive awareness is being in a resonance state. Being in this stable state is when cognition occurs. Activation: a cell’s activation is on (one) or off (zero) Connection weight: the strength of the impact of the signal from the sending and receiving cell Update rule: when the number of excitatory signals is greater than the number of inhibitory signals, the cell is active; when the number of inhibitory signals is greater than the number of excitatory signals, the Fall 2015 PSY 200 cell is inactive. The update rule describes the process of deciding whether the cell should be active or inactive. “Settle down”: the network eventually goes into a stable pattern “Error correction capabilities”: the network has the ability to correct errors by inactivating and activating the appropriate cells “Tolerate the loss of some cells”: the loss of a cell doesn’t mean that the brain stops working; it can continue to work even in the absence of some cells Feedback in networks can act to “clean up” noisy sensory information to make it consistent with what our systems expect. The pattern of excitation and inhibition creates a network’s expectations to stimuli. The feedback network in our minds is constructing contours when they do not exist. Neurons in area V2 of your brain “create” the illusory contours. Lecture 8 After being exposed to different stimuli in the environment, the neural network changes the connection weights in order to adapt. For example, if two neurons are active at the same time, the synapse will get larger to strengthen the connection between them. The network has changed the connection weights between the neurons. Hebb’s Rule Cells that are simultaneously active develop positive weights (excitation) An active cell develops negative weights with inactive cells (inhibition) The network gets exposed to a certain environment that excites certain cells. After becoming active, the synapses begin to change. The inactive cells are inhibited by the excited cells. Hebb’s rule ensures that the neural network is self-organized. A network of this type does not need an intelligence to set the connection weights. The network self-organizes in response to stimulation. The network remembers what it has previously experienced. If it cannot remember what it has experienced, it would not be able to Fall 2015 PSY 200 converge back into some pattern that represents that information based on the experience it previously had. We do not know the exact nature of the network involved in hand-eye coordination, but we know that it continually modifies part of itself to match up with the current situation. This is actually a good design feature, because the brain cannot know in advance every detail of the eye-hand system.
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'