Popular in Cognitive Neuroscience
Popular in Psychology (PSYC)
verified elite notetaker
This 13 page Study Guide was uploaded by Selin Odman on Monday September 19, 2016. The Study Guide belongs to 4140 at University of Georgia taught by Dr. Haas in Fall 2016. Since its upload, it has received 4 views. For similar materials see Cognitive Neuroscience in Psychology (PSYC) at University of Georgia.
Reviews for Test_1_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: 09/19/16
To study for exam: 30-40 Multiple Choice; 4-5 short answer (out of 50 points) Read book chapters and take notes along with PowerPoint slides Read articles handed out in class ***Know all of the key terms in the chapters. Make notecards with definition and application/why it’s important EXAM COVERS CHAPTER 1-4 and PART OF CHAPTER 5 (Up to pg 140 in Textbook) *Higher part of visual cortex will not be covered in exam ***Read articles handed out in class – know what was studied, why is was studied, how it was studied, and what they found *40 MC questions and 2-4 short-answer questions -“Describe ___” and write about 3-4 sentence 8/16/16 fMRI (functional magnetic resonance imaging) Good: good for descriptive, but not predictive measures – we cannot assume causation using fMRI Bad: People try to use it to assume that one region of the brain is connect to one function in your brain What we’re looking for in fMRI Levels of oxygen in the brain: neurons use a lot of oxygen, so determining where a lot of oxygen was just used, can let us predict which neurons were active -fMRI DOES NOT actually show us neuron activity because it does not measure action potentials -this can lead to a large delay; up to 6 seconds after the neurons have actually fired Example: We are interested in which part of the brain is in charge of understanding emotions Experiment idea: show emotional faces and ask people to determine which emotion they’re showing; then show a blank screen and collect data again with fMRI Conclusion: The part of the brain that lights up is in charge of processing emotions (This is a flawed experiment) -Forward inference: induce a state of emotion/situation and then use fMRI to measure brain activity Example: Making moral decisions involved the insula brain of the brain which causes people to feel emotional physiological distress (Sweaty palms, fast heartbeat) Reverse inference: Using prior research, we know that the insula is involved in emotions; so if the insula part of the brain is active, we can assume the task requires emotions -Insula is active when moral decisions are being made morality involves emotions How We Know What We Know Connectional Methods -Functional of a neuron depend on its input and output *There is really nothing a cell/neuron can do on its own – it must work with other parts of the body/brain -Tracing these connections can teach us what the cell does -It’s possible to label cells that provide input to the neuron as well as the cells that the neuron sends messages to. -Diffusion tensor imagine (DTI) provides a way to map connection in a non- destructive way of a living brain by measuring amount and direction of diffusion of water molecules *if water molecule is moving in linear path, it is probably part of the axon and makes up white matter *if water molecule moves in circulate path, it is probably part of the soma and make up grey matter Correlational Methods Invasive Methods -Microelectrodes can be implanted in the brain to record electrical activity of individual neurons of groups of neurons *This is a great way for researchers to measure action potential in the brain; it’s usually done if a patient is undergoing brain surgery and consents to research -Microdialysis samples the chemical makeup and concentration of brain fluid -Voltammetry measures the levels of neurotransmitters in a tissue by monitoring voltage changes in the probe Less Invasive Methods -Electroencephalography (EEG) does not give us a delay and we can better know when something is happening in the brain, but it’s harder to determine where in the brain something is happening *A cap is worn by the patient with electrodes all over it, measuring active potentials -Magnetoencephalography (MEG) monitors very small changes in the mag field around the head due to electrical changes in the brain *A magnet-type device is used to measure the field Indirect Methods -Positron emission tomography (PET) studies involve injecting small quantities of radioactive molecules into the body and monitoring how they are distributed in the brain -Magnetic resonance imaging (MRI) allows researchers to visualize structure of the brain in detail without radiation *fMRI -maps blood flow and oxygenation but has a delay due to both imaging methods and output from the neuron, but it’s accurate in telling us which part of the brain is activated *Diffusion tensor imaging (DTI) identifies connections between different regions *Voxel-based morphometry (VBM) maps the shape and thickness of brain regions Lesion Methods Lesions are areas of the brain that are damaged by disease or injury -Traumatic brain injuries, stroke or tumors are through to results in lesions which affect behavior -In the 1860s, neurologist Paul Broca studies patients who had difficulties producing speech. Stimulation Methods A Toolbox of Complementary Methods Know the parts of a neuron*** Soma, Dendrites, Axon, Myelin, Axon Terminal, Terminal Ruttun, and direction of neuron, white matter (has fatty tissue like axon)/grey matter (no fatty tissue like soma) Lesion Methods -Patients were brain injuries/diseases can be observed with different behavior like talking too much or too little. *These experiments are done on animals like mice: will lesions to certain parts of the brain affect the way the mice navigate a maze? -Trans-cranial magnetic stimulation (TMS) can create short-term lesions in the human brain *A magnetic pulse is passed through the brain and alters brain composition by altering neurons in the brain – when the magnetic pulse stops, the brain goes back to normal -Temporal parietal junction: part of the brain which lets us try to understand someone else’s perspective -Electric Convulsion Therapy (ECT): still used today in large hospitals for treating severe depression. *Why it works is not exactly clear…but there are side effects like memory loss *TMS is sort of like targeted ECT on a smaller scale – can possible help with depression Optogenetics -Ion channels found in phytoplankton respond to light -Scientists have taken these ion channels and implanted them into mice brains, forming a mouse brain with parts that are reactant to light. *This allows researchers to shine light onto parts of the brain to turn neurons on or off The Big Questions in Cognitive Neuroscience Why have a brain at all? How is information coded in neural activity? -Neurons are firing off and receiving signals, but we don’t know much about the language of neurons. How does the brain balance stability against change? -Our brain, like our bodies, maintain homeostasis -Memory is associated with changes in our brain structure and function, so how does this relate to homeostasis? How does vision have so little to do with the eyes? -There is a basic understanding of how eyes work -> light goes through cones in our eyes to project an image in the back of our brain which we perceive -However, perception is created in our brain but it’s not understood through our eyes. How does the brain stitch together a picture of the world from different sense? -Eating/sensing/feeling food -Playing a sport feels like one single experience, but it’s actually very technical and consists of many singular parts How does the brain control our actions? -Even just raising our arm is a multi-step action -There are different neurons responsible for each step but they work together What is consciousness? -Why is this important for evolution? -Does the brain process this automatically or was it an evolutionary accident? How are memories stores and retrieved? -Memories are finite -> if some memories come in, some have to go out -How does the brain prioritize this system? What do brains sleep and dream? -Sleeping and dreaming is usually known as a restorative state -Can also enhance memory -Dreams can be a testing ground for our ideas before we actually do them How does the human brain acquire its unique ability for language? -What makes this ability possible for humans? How do we make decisions? What are emotions? How do I know what you’re thinking? What causes disorder of the mind and the brain? The Payoffs of Cognitive Neuroscience Healing the disordered brain -Parkinson’s, severe depression -Changing the way we view mental illness Enhancing human abilities -Making memory stronger/better Blueprints for artificial cognition -Hoping to understand the brain better Brain-compatible social policies -Helping us to understand how the brain helps us make social decisions Near infrared spectroscopy (NIS) – Patient wear a cap with a light-emitting probe which shines a light into someone’s skull. The light will hit the cerebral cortex and reflect in a certain way based on how much oxygen is present. -These techniques require someone to be very compliant – so they are not practical for other uses like court cases or marketing Chapter 2 – Neuroanatomy Gyri – bumps in brain Sulci- folds and crevices in brain Although brains look very different across species, there are some consistencies. The Common Features of Every Central Nervous System Prosencephalon (forebrain) Mesencephalon (midbrain) Rhombencephalon (hindbrain) Spinal cord Forebrain - Telencephalon: cerebral hemispheres (cerebral cortex, subcortical white matter, basal ganglia, basal forebrain nuclei) Diencephalon: Thalamus, hypothalamus Midbrain - Mesencephalon Getting Oriented in the Brain There are specialized terms for directions within the nervous system: Rostral – Caudal: nose – tail axis (best used for animals on 4 feet) Doral – Ventral: back – belly axis (associated with fish) Anterior – Posterior: front – back axis Superior – Inferior: top – bottom axis Example: Superior frontal gyrus – a bump in the front, top part of the brain Medial – towards the middle Lateral – towards the side Ipsilateral – on the same side Contralateral – on the opposite side Distal – far end of the limk Proximal – nearest part of the limb When describing the brain with MRI images, we usually describe the brain with 3 different “slices” -Sagittal: cut between left and right hemisphere -Axial: cut through half of brain (top and bottom) -Coronal: cut through half of brain (front and back) Separate Systems for the Inner and Outer Environments Peripheral nervous system has two parts -Somatic nervous system: deals with external world; sensory and motor neurons carry information about voluntary movement and conscious awareness -Autonomic nervous system: deals with internal world; sensory and motor neurons guide automatic processes Central Nervous System (CNS) – consists of brain and spinal cord Peripheral Nervous System (PNS) – anything outside of brain/spinal cord *Sensory system: afferent SAME: Sensory Afferent – Motor Efferent *Motor system: efferent *Somatic: have conscious control over muscles like moving our arm *Autonomic: no control over muscles like our heart beating *Sympathetic: Fight or flight *Parasympathetic: rest and regenerate A Nervous System with Segmental Organization The spine is divided into 4 segments -Cervical -Thoracic -Lumbar -Sacral Each of these segments affect different parts of the body The Spinal Cord Circuits within a segment: spinal reflexes Complex circuits across segments: Central Pattern Generators Spinal cord injuries can be treated with stem cells since its function is determined by its location – not by its DNA. You can put it in the cerebellum or the frontal cortex, and it will perform those respective functions. The Brainstem Medulla Oblongata and Pons -Medulla is important for breathing, heart rate, blood pressure -Pons is important for some overlapping functions and things like eye movement, bladder control, swallowing, arousal, facial expression, posture The Midbrain Has groups of nuclei – groups of multiple neurons -Superior/Inferior Colliculus deals with visual and auditory stimulation by controlling how our bodies outwardly react to them (movement of body) -Substantia nigra houses dopamine neurons which create dopamine, a chemical which helps us with fine motor skills -Raphe nuclei is important for serotonin system; this is where SSRIs target, inhibiting the reuptake of serotonin so that more serotonin will remain within the neurons, affects the brain more -Locus coeruleus produces norepinephrine important for arousal and awareness The Cranial Nerves Most of the cranial nerves emerge from the brainstem -Vestibular system helps us to orient ourselves with the outside world *i.e. if we were flipped upside down with our eyes closed, we would be able to sense that Circuitry of the “Little Brain” Located in the cerebellum -Sensory motors helps us achieve complicated, coordinated tasks -Motor memory helps us remember how to ride a bike -Forward planning of motor movement “Forward model” that the cerebellum predicts sensory outcomes from motor movement to plan the new or next motor sequence *Cerebellum is thinking 4 or 5 steps ahead of our sensory motor system The Hypothalamus/Thalamus -Hypothalamus is important for homeostasis *Circadian rhythm, heat dissipation, appetite and thirst, heat conservation, satiety, hormonal regulation -Thalamus relays sensory signal to the brain and motor signals to the body Neurons: A Close-Up View -Temporal Summation: adding up of electrical signals over time -Spatial Summation: adding up of electrical signals over space -Axon hillock decides that electrical signal is enough to start an action potential which will go from axon to axon terminals, translating to the next neuron -Neurons have four important regions *Dendrites: branching projections that collect information *Soma (cell body): includes dendrites *Axons: long strip of myelin sheathed cells which carry action potential *Axon terminals: small swellings that release signals to affect other neurons -Chemical signals, known as neurotransmitters, cross small gaps, known as synapses -Estimated about 500 trillion synapses in human brain *Synapse: a connecting space between two axons – neurotransmitter signal goes from axon terminal, into the synaptic space, which then interacts with receptors in neighboring axon. ***The neurotransmitters doesn’t enter the receptor ion channels, it works as a key to turn them on/off, allowing charged ion like potassium or sodium to move in/out of axons -examples of neurotransmitters: serotonin, dopamine, adrenaline Many different types of neurons Neurons can be classified by their function: -Sensory neurons carry information to the brain -Motor neurons carry information from the brain to the muscles -Interneurons convey the signals around the nervous system Neurons can be classified by their shape: -Multipolar neurons have multiple dendrites -Bipolar neurons have one dendrite and one axon -Monopolar neurons have only one projection from the soma, which branches to form the axon and the dendrite Glial Cells Glia have multiple roles within the nervous system: -Speeding up neuron signaling -Regulating extracellular chemicals -Allowing neuron to modify their connections Oligodendrocytes: in the CNS, work with multiple cells Schwann cells: in the PNS, works with one cells -These cells wrap myelin around axons which helps speed up the signals COPS: Central – Oligodendrocytes – Peripheral – Schwann Nodes of Ranvier are small gaps in myelin sheath which work to maintain action potential…the action potential is somewhat unstable, and the gaps between myelin help promote the action potential Astrocytes regulate extracellular chemical and regulate local blood flow -Crucial for blood-brain barrier: which controls which neurotransmitters can be transmitted from our blood to our brain -Example: Allows for pre-cursors of dopamine (L-dopa) to transfer through the blood-brain barrier which can be turned into dopamine in the brain -Example: Allows for pre-cursors of serotonin (tryptophan) to affect the levels of serotonin in our brain Microglia provide immune system functions for the CNS OLIVER SACKS DISCUSSION Neurological Battery Conducting many different tests including imaging, behavioral studies, and other quantitative/qualitative studies to assist in coming up with a diagnosis -i.e. Alzheimer’s is mostly diagnosed by behavioral observations – can only be quantitatively diagnosed post-mortem posterior cortical atrophy (PCA) Usually these patients deteriorate exponentially There is no cure…some medicines can slow the atrophy There are ethical questions about these conditions: what is the value of diagnosing, or knowing if you’re more prone for Alzheimer’s? -i.e. genes associated with early on-set Alzheimer’s Relationship between our brain and our physical self Our thoughts, emotions, and beliefs affect the way we can deal with situations “Music processing” is more associated with 3-D functions than the 2-D function that normal reading requires ***Articles related to topics on ELC Blindsight – seeing is not connected fully to the eyesight. The brain helps us predict where we may see things. Stroke patients usually exhibit blindsight – their body may be inhibited but their brain is aware of their entire body Concentration Gradient – motivation to travel to a location from high to low concentration Electrical Gradient – describing motivation of charged particle to travel to a location to create a charge closer to 0, or electrical equilibrium *Positive charged will travel towards neg charged area to create area closer to neutral charge Ions in neuron: K+, Na+, Cl-, Ca++ K+ motivated to leave (weak) Na+ motivated to enter (strong) Cl- motivated to enter (weak) Ca++ motivated to enter (weak) A strong desire to move in/out is going to cause the change to happen quickly ***Na+ will quickly enter the neuron, causing a change in overall charge, which causes the action potential! Action Potential If the electrical potential of the neuron reaches -55mV by allowing Na+ to enter, the axon hillock will decide to fire off an action potential. *-55mV is known as the gate threshold, which opens voltage gated Na+ channels (at the axon hillock), allowing for a rush of Na+ to enter the neuron, causing depolarization (charge becomes closer to neutral) If Cl- enters the neuron, lowering the electrical potential even more, it will be less likely for an action potential to fire off When the neuron is depolarized and reaches a positive charge, the sodium gates will close and the potassium gates will open, lowering the charge again, causing repolarization. A refractory period causes a larger influx of K+ ion, causing the potential to go below-70mv. This lowers the chance of an action potential, allowing the neuron to take a break. The Na+/K+ pump will eventually bring balance. The potential will then return to the rest potential, -70mV, with both Na+ and K+ gates closed. Types of Neurotransmitters Monoamines – dopamine, epinephrine, norepinephrine, serotonin, melatonin Types of Receptors Ionotropic receptor – a neurotransmitter enters synaptic cleft and interacts with receptor, either opening or closing ion channel Metabotropic receptor – a neurotransmitter interacts with receptor (G-coupled protein receptor) and will change some type of metabolic activity Signaling for Neurotransmitters to be released Action potential reaches synapses, affecting the voltage change in the neuron. Ca+ is motivated to enter the cell, signaling synaptic vessels to travel to the membrane of the terminal button (end of synapse) -Vessels fuse with membrane, releasing neurotransmitter into synaptic cleft, binding with receptor, affecting other parts of the brain and other neurons. Neurotransmitters (NT) only bind to receptors for a short time and need a way to be removed Degradation: the NT is broken apart Diffusion: NT moves down the concentration gradient and out of the synapse Reuptake: NT is transported back into the original cell *The cell can pretty much recycle the NT it just released *SSRIs, serotonin-selective reuptake inhibitors, inhibit the reuptake of serotonin into the cell that released it, making the effect of serotonin more intense, causing the serotonin to remain in the synaptic cleft for longer. Neurotransmitters Agonist – mimics neurotransmitters; increases effects Antagonist – opposite effects of agonist; inhibits effects Encoding stimuli in spikes Input: Natural stimulus Output: sensory nerve impulses that comes in very unique bursts. CHAPTER 4 Changes in the Body Plan The homunculus is the map of the body within the sensory and motor cortices -Certain body parts seem exaggerated because they are more sensitive (hands are bigger than hips) People with one hemisphere of their brain removed at a young age can function normally because of brain plasticity. Phantom limb syndrome – feeling that a limb is still present even after amputation -The brain keeps signaling that the limb is there or pain is still present because the brain has gotten used to having signals from that limb. th SEPT 6 Changes to Sensory Input Example: aucepetol lobe, usually used for vision, is allocated or rewired for hearing or tactile processes in blind people. Article: Navigation-related structural change in the hippocampi of taxi drivers -Our brains can change shape as we do a task over and over again Spatial part of brain – Peridol lobe The Role of Relevance: Gating Plasticity with Neuromodulation The behavior must be relevant to the organism to result in plasticity When cholinergic brain cells are knocked out, your brain will not adapt when your body repeats certain tasks -i.e training to use one part of your body for a task…brain will not adapt if cholinergic is knocked out Maps Adjust themselves to the available brain tissue If parts of the brain are removed, it will continue to distribute the skills over the entire brain. Similarly, if a part of the signaling receptor is removed, then the brain will adapt to use the space for a different signaling receptor. It’s efficient for the brain to have a hard code for how the basic things should work – but not every single bit of our being -i.e. circadian rhythm changes according to our environment and situation; it’s not rigid and planned for 24-hours Sensitive Period in Language The best time to learn a language is from 0-7 The window almost closes after 17 years old Adults have a harder time differentiating between the sounds of letters in different languages, making it harder to learn languages -i.e. Japanese adults cannot differentiate between “r” and “l” – babies can do this, so they can differentiate between sounds -It’s not a skill that can be learned either…it’s one of those “use it or lose it” skills Aspects of the Brain are Programmed We are born with certain reflexes, such as grasping and sucking Sperry conducted studies of the newt visual system, and developed the chemoaffinity hypothesis: -Connections within the visual system are preprogrammed o follow chemical cues to reach their target -Chemical cues can be attractive or repulsive Neurons Compete for Limited Space -Initially, axons with visual info from the thalamus initially branch widely in the cortex. -Then, they segregate into eye-specific patches based on the patterns of activity -If you block activity from retina (incoming activity is blocked), then the cortical axons will not differentiate and stay overlapped -Shutting one eye leads to the visual cortex allocating more space for the eye that is open *We are very circumstantial beings!!! CHAPTER 5 What is it like to see? Visual illusions, such as the Mach band illusion, teach us about the visual system What we perceive is a poor representation of the stimuli in the world – all perception is a construct of the brain We are susceptible to illusions, so our brain does not show us how the world is exactly -When something is a little bit different, we perceive it as being very different Our brain is crucial for allowing us to understand the world around us, not just see it. -Someone who was blind for most of their lives, but then regained vision was not able to use the signals coming from the eyes to the brain to make sense of the world. -SEEING something is not the same as understanding it. Even though our eyes see, our brain is what understands 30% of our brain is involved in visual processing…other senses use less than 10% of our brain Signal Transduction Transduction is the process of converting info from the outside world into the electrical and chemical signals of our nervous system -Wavelengths/photons interact with molecules in our photoreceptors which affects the ions going in/out, affecting the likelihood of an action potential The sensory receptors that we possess determines what we perceive. Visible light is only 1/10billiononth of all wavelengths The Eye and Its Retina Cones process color and fine detail and rods take care of things like subtle light, depth, and movement -There are A LOT more rods than cones in your eye -There are different types of cones that are sensitive to certain light colors Cellular layers of the retina Photoreceptors: transduce light signals Horizontal cells: communication between adjacent parts of retina Bipolar cell: carry info from photoreceptors to retinal ganglion cells Amacrine cells: allow communication between different parts of the retina Retinal ganglion cells: pass info from eye to brain Each neuron has a receptive field in which it is sensitive to light at a particular point in your field of vision The neurons have a center-surround organization, with the center sensitive to light, the surrounding of that part not sensitive to light and so on… On Center Cell: the middle of the cell (receptor cell) is sensitive to light and fires more action potentials Off Center Cell: the receptor cell is not sensitive to light in the middle, and prefers light surrounding a dark middle Light from our eyes is sorted in the Lateral geniculate nucleus which dissociates vision -Temporal vision is sorted into left hemisphere -Nasal vision is sorted into right hemisphere *Left visual world processed by right hemisphere : Right visual world is process by left hemisphere Lateral geniculate nucleus: two pathways are parvocellular and magnocellular Parvocellular – processes colors, gets info from cones Magnocellular – processes detail and light, get info from rods
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'