Cognition Lecture Notes 2024 PDF

Welcome to Cognition: Fundamental Theories Summer session II 2024 Check- in: on a scale of 1 2 sheep, how are people feeling today? If you are feeling like a… 1. Raise one hand 3 4 2. Raise both hands 3. Hands down and smile 4. Stand up,...

Welcome to Cognition: Fundamental Theories Summer session II 2024 Check- in: on a scale of 1 2 sheep, how are people feeling today? If you are feeling like a… 1. Raise one hand 3 4 2. Raise both hands 3. Hands down and smile 4. Stand up, hands up Today’s agenda Review The Brain! Methodology! How to find empirical articles? Wrap up What is the black box problem? Our inability to observe the mind directly Name one pro and one con of behaviorism Pros ○ Very scientific way to study behavior ○ Findings can be generalized to most human behavior ○ Can be used in increase behavior in individuals (education, raising children, recycling) Cons ○ Only tells us about observable behavior ○ Can’t account for other mental processes (eg., mental representation, creativity, explicit memory,...) What is cognitivism? Making inferences about the mental processes that underlie behavior. Action potentials are … ALL OR NOTHING! What are released by a neuron as a results of an action potential? Neurotransmitters! What are the steps of neural communication? 1. Receives neurotransmitters from neuron before What are the steps of neural communication? 2. Neuron receives neurotransmitter via dendrites, and depolarization begins. What are the steps of neural communication? 3. If electrical signal reaches past resting potential, action potential is fired. What are the steps of neural communication? 4. Action potential travels down the axon What are the steps of neural communication? 5. Myelin sheath and Node of ranvier help the action potential to travel faster and stronger What are the steps of neural communication? 6. Action potential causes the neuron to release neurotransmitters via axon terminal The Brain Composed of ~86 billion neurons Outer surface is known as the cortex Cortex is divided into four main “lobes” ○ Frontal ○ Prietal ○ Occipital ○ Temporal The Brain Composed of ~86 billion neurons Outer surface is known as the cortex Cortex is divided into four main “lobes” ○ Frontal ○ Prietal ○ Occipital ○ Temporal Two Hemispheres Brain is composed of two symmetrical (structurally) hemispheres Each hemisphere receives input about as well as controls, the opposite side of the body Communication between the two hemispheres occurs at the corpus callosum Two hemispheres Left hemisphere ○ Language ○ Local detail Right hemisphere ○ Spatial processing ○ Global configuration Not “right brain/ left brain” folk psychology! Local vs global processing Local vs global Local = fruit Global = face Severed corpus callosum The cortex Surface of cortex is composed of cell bodies (gray matter) Connections between neurons are deeper (white matter) Why wrinkled? ○ Maximize surface area to volume ratio ○ Optimal blood flow ○ Gyri and sulci Gyrus – ridges Sulcus – valley  Frontal lobe ○ Motor, planning, working memory, speech production ○ Larger than any other mammal Parietal lobe ○ Sense of touch, body position,motor cortex, spatial processes Occipital lobe ○ Visual processing Temporal lobe ○ Vision, object recognition, auditory processing, smell, taste and memory Subcortical structures Gets name “subcortical” because they are “under the cortex” Thalamus ○ Sensory relay station ○ Integrates and sends information to the cortex Hippocampus ○ Memory formation, navigation and spatial processing Amygdala ○ Emotion processing Methodology Brain Lesions How can we study the mind? So far we’ve talked about two methods of studying the mind ○ Introspection ○ Single cell recordings of neurons Based on our knowledge of brain regions and their functionality, we can ask interesting questions about how it works! This can done through multiple ways ○ Lesion studies ○ Brain imagining ○ Event-Related Potentials (ERPs) ○ Experiments Lesion Studies Study patients with brain damage to specific regions. ○ In humans, results of traumatic brain injury/ medical (eg. stroke, infection) ○ In animal studies, can be induced. Behaviors are observed before/lesion/damage and after. ○ How did the behaviors change? ○ Make inferences about areas of brain based on changes to behavior. Double dissociation ○ Compare patients to find double dissociations. ○ Examples: Broca's and Wernicke's Aphasias Phineas Gage 1860 Double dissociation When 2 mental processing are independent of each other Damage to brain area X selectively impairs task A but not task B Damage to area Y selectively impairs Task B but not task A Area X → responsible for processing mental processing in task A Area Y → responsible for processing mental processing in task B Example of double dissociation Example - Damage to the hippocampus impairs the ability to recognize buildings, but not recognizing faces - Damage to fusiform area impairs the ability to recognize faces, but not recognizing buildings - Hippocampus → object recognition - Fusiform area → face recognition Broca’s Area Damage → Broca’s Aphasia Issues with language production, little to no issue with language comprehension Content words only, no function words ○ “I want the cup” vs “me cup” Also involved in fine motor skills, like using utensils and tools. Wernicke’s Aphasia Fluent speech but makes little sense. Can include made up words, word substitutes Struggles with comprehension Lesion Studies Observing changes in behaviors before and after brain injuries, we can make inferences about what these areas of the brain do. Methodology Brain Imaging Event Related Potentials (ERP) Remember: Neurons communicate via electrical changes We can measure these electrical changes in electrical activity during cognitive tasks. EEG – Electroencephalograph ERP – Event related potentials High temporal resolution, low spatial resolution ERP experiment example N170 Larger amplitude for faces than cars Earlier peak for faces than car fMRI fMRI – functional magnetic resonance imaging Neurons need oxygen to function. This means that blood flows to areas of the brain that are active fMRI capitizales on this and measured the changes in blood flow in the brain. ○ Blood Oxygen Level Dependent (BOLD) Neuroimaging takes places when a participant's is performing a cognitive task. High spatial resolution, poor ○ Imaging takes place both before and during the task temporal resolution ○ Use subtracting methodology to understand changes in blood flow. Positron Emission Tomography (PET) Participants are injected with radioactive tracers ○ Yes you heard that correctly Placed in machine, told to some cognitive task ○ Measured before and during task ○ Machine measures the breakdown of radioactive tracers. Where the machine register more activity, there is more blood. Poor temporal and spatial resolution Subtraction Method - = during task Before task Areas involved in (control) the task Transcranial Magnetic Stimulation (TMS) Uses magnetic field to temporarily disrupt electrical activity in a certain region of the brain “Reversible brain damage” Effects on cognition are then assessed Urban legend alert! “We only use 10% of our brain” Any problems with this? Problems The brain uses a lot of energy In brain imaging, the entire brain shows activity In single cell recording, every neuron shown activity at some time Maybe we don’t use 100% at a time ○ Patter is what matters ○ All firing at once is really bad seizure  Methodology Laboratory Experiments Experimental Psychology Compare two or more experimental conditions to find systematic differences Uses scientific method and statistical analysis ○ independent variable, dependent variables. Most common dependent variables are: ○ Accuracy – number (or %) of correct response ○ Latency – time to make a response Uses statistics to explore differences between conditions Accuray Example: word length effect Compare # of correct on monosyllabic list to # correct on multisyllabic list ○ IV: number of syllables ○ DV: number of words recalled Typically, lists of multisyllabic words are recalled significantly worse than monosyllabic ○ Why? Mental Chronometry Neural communications takes time Every stage in a mental process takes some amount of time (latency) If two similar processes take reliably different amount of time, there is some difference between them Theoretical source of the difference up for debate  Read the color of the word not what the Latency text says Example: Stroop task Compare time to say color of congruent words with time to read incongruent words ○ IV – congruency of words and font color ○ DV – verbal response time Other dependent variables Scores on a post-manipulation survey or task ○ Pre-test and post-tests Qualitative analysis of speech and writing Presence or absence of action Motion tracking Motion Tracking Eye tracking Record eye movements while looking at stimuli or reading Can be used to create heat maps showing where people look Motion Tracking Other forms of motion tracking are less common (but cool!) Lip tracking Mouse tracking Motion tracking is interesting as it provides continuous data Ecological Validity One last important thing … Behavior and cognition might be different “in the wild” The degree to which an experiment’s findings would hold up in everyday life is called ecological validity. Homework assignment Find an empirical article (presenting new data– not a chapter or review article) Choose a topic that interests you 1. Summary and analysis of the article a. What questions did the researchers address?(talk about any relevant theories and hypotheses) b. How did they test hypotheses? c. What did they find d. How does this fit in what we have learned in this class 2. Discussion of how this article relates to your own experience in the world. 3. Proposal of a follow up study. a. Fixing issue with the original study b. Or expand upon the original study How do I find and read empirical papers? Empirical articles An article that reports research based on actual observation or experiments. (reports new data) Typical structure of the an empirical article: ○ Abstract ○ Introduction ○ Method ○ Results ○ Discussion Where do I find Papers? Use online database The UCSC library gives you access ○ PSYCInfo ○ Web of science Google Scholar Refining your Search Terms Search Google Scholar for “memory” = 7,260,000 results ○ You can’t read 7,260,00 papers ○ Some of them are on computer and medicine (not really relevant) ○ Search for “retrieval-induced forgetting = 87,000 results ○ No thanks! Search “retrieval-induced forgetting” educational materials” = 46 results ○ Much less painful How do I read an empirical article? For each section, the authors are trying to provide specific information Abstract ○ Gives you a brief overview of the entire paper. When choosing an article, I recommend reading the abstract first to see if it interest you. How do I read an empirical article? Introduction ○ Background information on the topic ○ What is the research question? ○ What is the context in which this research is being done (AKA why does this matter?) ○ What is the hypothesis being put forward by the authors(s) ○ What informs the hypothesis How do I read an empirical article? Methods ○ How did the researchers test their hypothesis? ○ What did the participants do? Results ○ What was the main results? Discussion ○ What conclusions can be drawn from the results? ○ Was the hypothesis supported? ○ How did the findings connect to the rest of the literature