Psychology 263 Midterm Exam #2 Study Guide Fall 2024 PDF

**Psychology 263** **Midterm Exam \#2 Study Guide** **Fall 2024** **Working Memory/Attention and Memory** The three components of Baddelay's model of working memory (the central executive and the slave system)...you should know what they are and how they work, what each system is responsible for...

**Psychology 263** **Midterm Exam \#2 Study Guide** **Fall 2024** **Working Memory/Attention and Memory** The three components of Baddelay's model of working memory (the central executive and the slave system)...you should know what they are and how they work, what each system is responsible for (slides 5-26). Central Executive: oversees and allocates resources, directs attention. - Controls and regulates cognitive functions (decision making, problem solving, task switching). - It has no storage capacity of its own but manages the flow of information between the slave systems and long-term memory. Phonological Loop (Slave System): manages verbal/auditory information through a temporary storage system. - Phonological Store: the "inner ear" that holds auditory information for a short duration (1-2 seconds). - Articulatory Control Process: the "inner voice" that refreshes the information through subvocal rehearsal, preventing decay of auditory traces. - Essential for tasks like language learning, reading, or recalling verbal instructions. Visuospatial Sketchpad (Slave System): deals with visual and spatial data. - Helps in tasks that involve navigation, visual imagery, and spatial awareness (ex; finding your way around a building, picturing objects in space). - Like the phonological loop, it has limited capacity but specializes in non-verbal information. Episodic Buffer (added later): integrates information across different modalities (auditory, visual, and spatial) and links to long-term memory. - It acts as a temporary store that combines information from the phonological loop, visuospatial sketchpad, and long-term memory to form coherent episodes or experiences. - Ex; allows you to remember a specific event involving both sight and sound. Articulatory suppression: what is it, why we use it, how it influences processing (slides 11-14). When you repeat a word or series of words (like "the" or "la-la-la\") while doing another verbal task. - This keeps the articulatory loop busy and prevents the rehearsal of new auditory verbal information and translation of visual material into phonological code. - If you are asked to remember a list of words while saying "the" repeatedly, you won't be able to repeat the words in your head, so you will remember fewer of them. Why: - Stop people from repeating things in their heads (subvocal rehearsal). - Test how memory works without the help of verbal repetition. - See how much the brain can handle when doing multiple tasks at once. How: - Block rehearsal (you can't mentally repeat words or numbers, so they fade from memory faster). - Reduces memory capacity (it becomes harder to remember things like lists or instructions). - Hurts word recall (it makes tasks like reading or remembering words harder because the brain's verbal system is busy). - Interferes with similar sounds (normally, we confuse words like sound alike, but articulatory suppression makes that confusion less noticeable). The word length effect: what is it and what is it evidence for (slides 12-13). The idea that it's easier to remember short words than long words. - Ex; it's easier to recall a list of short words like "cat," "dog," and "sun" than longer words like "elephant," "alligator," or "refrigerator." The word length effect shows that the phonological loop in working memory has a limited capacity. - Since longer words take more time to rehearse in your head (subvocal rehearsal), they are more likely to be forgotten. The visual similarity effect: what is it and what is it evidence for (slide 25). The difficulity people have in distinguishing between items that look similar, even if they have different meanings. - Ex; if you are shown a list of letters like "O," "Q," "D," and "C," you might confuse them because they have similar shapes. The visual similarity effect is evidence for the involvement of the visuospatial sketchpad in working memory, which processes visual and spatial information. - It shows that when we rely on visual memory, our brains can struggle to distinguish items based purely on how they look if they are visually similar. Working memory span: what is it, how is it tested, and what is the influence of working memory span on other cognitive tasks (slides 28-35). How much information you can hold and work within your mind at the same time. - People with a bigger working memory span can remember and manage more things at once. How it's Tested: it's tested by giving people tasks that involve both remembering and doing something else at the same time. - Reading span: you read sentences and remember the last word of each. - Operation span: you solve math problems and remember words in between. - Digit span: you repeat back a sequence of numbers. Affect: - Attention (people with bigger working memory span can stay focusd better and ignore distractions). - Understanding (they're better at understanding complicated sentences or reading texts). - Problem-Solving (it helps in solving puzzles or doing tasks that need you to think through steps). - Multitasking (a larger span makes it easier to juggle multiple tasks at once). You should know the evidence that was inconsistent with the original notion of short term-memory and how working memory can account for this evidence (slides 36-41). Problem \#1: neuropsychological evidence. - Patient with small span and normal long-term memory. - Impairment should create a severe bottleneck in information transfer to long-term storage. Solution: span depends on phonological coding while long-term memory likely depends more on meaning (phonological store damage should not affect long-term learning). Problem \#2: transfer failure. - According to most models of STM, any piece of information that remains in STM long enough should transfer to LTM. Problem \#3: individuals can accurately perform two tasks at the same time (not common). - If the capacity of STM is 7+2 items, then performing two tasks simultaneously should overload the 7+2 rule, meaning performance should suffer. Solution: dual task performance should be good if; - The items held on-line are stored in different modalities (ex; something in the visual store, something in the phonological store). - The attentional demands don't exceed the ability of the central executive (can't predict when this happens, we only know that adequate performance means CE can handle demands of tasks while poor performance means CE can't). What is the influence of dividing attention on memory? At encoding? At retrieval? (slides 47-53). At Encoding: dividing attention has a big negative effect (you don\'t learn or store the information as well). At Retrieval: dividing attention has a smaller negative effect, but it still makes recalling the information harder. **Memory failure** Real world studies of forgetting: what are the findings and how do they compare to Ebbinghaus' forgetting curve (slides 5-18). Forgetting happens more slowly: people forget information more gradually compared to Ebbinghaus' rapid drop in memory. - Real-world memories tend to stick around longer, especially if the information is meaningful or used frequently. Retention is higher: people remember more information over time when it's personally relevant or connected to everyday experiences (ex; remembering the plot of a favorite movie or skills you use at work). Ebbinghaus' Forgetting Curve: He studied forgetting using nonsense syllables and found that forgetting occurs very rapidly at first, with a sharp drop in memory within the first hours or day after learning. - The forgetting curve shows that we lost most of the information soon after learning, but a small portion is retained for much longer. Real-world studies show that people remember meaningful information longer and more steadily than the steep decline suggested by Ebbinghaus' forgetting curve, which was based on learning random, meaningless data. What are the three main theories of forgetting? What is the evidence for each, what are the criticisms/problems with each (slides 19-49). Decay: memories fade over time if they are not accessed or rehearsed. - Research shows that forgetting does often increases with time. - Ebbinghaus\' forgetting curve supports this idea, demonstrating that memory strength decreases as time passes. Criticisms: - Lacks explanation for retrieval (just because time passes doesn't mean the memory is gone). - Doesn't account for other factors (doesn't explain why some memories are retained for long periods, especially if the information is meaningful or regularly used). Interference: other memories disrupt recall. - Proactive interference: old memories interfere with the recall of new memories. - Retroactive interference: new memories interfere with the recall of old memories. Criticism: - Not always consistent (sometimes people can remember old and new information without interference, suggesting that other factors play a role). - Complexity of memory (the interaction of different memories can be complicated, making it hard to determine the extent of interference). Retrieval Failure: memories are stored but hard to access without cues. - Emphasizes the importance of cues and contexts in retrieving memories. - Providing retrieval cues can improve recall. Criticisms: - Over-reliance on cues (not all memories can be retrieved even with cues, suggesting that retrieval failure is not the only cause of forgetting). - Doesn\'t address initial encoding (why some memories are encoded poorly in the first place, which can lead to later retrieval problems). Perseveration, what is it? (slides 20-21). The consolidation of information to memory. - If preservation is interrupted in any way the trace will not be consolidated, and recall will not be possible. - The longer the preservatory period, the stronger or more consolidated the memory trace (more preservation = better recall). - Preservation is STM, consolidated trace is LTM. You should know how sleep influences memory (slides 23-26 + in class video). If preservation is critical to LTM, then going to sleep immediately after learning should help memory. - Learn a short list of Ebbinghaus-type nonsense syllables (ex; TUV, BIJ), then sleep or stay away for 1-8 hours prior to test. - Those who sleep recall better than those who stay awake. - Memory is even better if we prevent subjects from dreaming while they sleep. How circadian rhythms/time of day influence cognition and memory (slide 31). Circadian rhythms influence when we feel most alert and capable of learning and remembering. - Morning vs evening. - Memory isn't as good if sleep occurs in the afternoon. Proactive and retroactive interference: what they are and how they influence memory (slides 32-37). Proactive: information you've learned prior to a learning episode disrupts your ability to remember that information. Retroactive: information you learn after the original learning episode interferes with the previously learned material. The suggested causes of interference and forgetting according to McGeoch (slide 38). McGeoch thinks that inability to recall something is due to subjects recalling unwanted memories (interference). - Information is never actually lost. Three mechanisms that can cause forgetting: - Response competition: two or more potential responses to a memory query. - Altered context: context dependent memory (memory worse when tested in a different context/no retrieval cues). - Set: a special version of context effects (where do I know that person from?) State-dependent memory and encoding specificity, what they are (slide 47-48). State-Dependent Memory: memory is improved when retrieval occurs in the same state as encoding (ex; internal context). Encoding Specificity: like state dependency, match between contexts at test and retrieval are key (ex; external context). **Knowledge, Semantic Memory, False memory** Know the distinction between episodic and semantic memory (slide 3). Episodic Memory: type of LTM that involves the recollection of specific events, experiences, or episodes from one's life. - Personal experiences (graduation, what you wore, who was there, how you felt). Semantic memory: type of LTM that involves knowledge of facts, concepts, and general information that is not tied to personal experiences. - Ex; knowing that the Earth orbits the Sun, or the capital of France is Paris. The dictionary definition, family resemblance, and prototype theories of semantic knowledge: the predictions each theory makes, evidence for/against the theories, and criticisms of the theories (slides 4-13). Dictionary-Like Definition: easy for comparison between categories, but you can't know a concept without knowing a definition/some items have multiple definitions. - Ex; dictionary definition for dog: a dog is an animal with 4 legs, a tail fur, and it barks. - Against: vagueness ("game" can refer to various types of play). Criticisms: the theory fails to account for the flexibility and variability of natural language. - Oversimplifies. Family Resemblance: probabilistic definitions. - Ex; probabilistic definition for dog: fit eh thing in front of me has 4 legs, a tail, fur, and it barks, then it\'s probably a dog, if not, it probably isn't a dog. - Advantage: necessary vs sufficient conditions. - Disadvantage: it can\'t account for unique cases (what if something doesn't look like it belongs to a category even though it does? /vice versa). Criticisms: the theory is somewhat vague and does not provide clear guidelines for categorization. - Struggles with categories that have a clear defining criterion. Prototype Theories of Sematic Knowledge: suggests that individuals categorize concepts based on an idealized or average representation (the prototype), of that category, rather than a strict definition or a family resemblance structure. - Advantage: people make faster categorization decisions for typical members of a category than for atypical members. - Disadvantage: some categories do not seem to have clear prototypes (ex; legal or mathematical categories). Criticisms: the theory does not explain how individuals handle exceptions or edge cases in categories. - Oversimplifies the processes involved in categorization, overlooking the role of context. Prototypes, what are they, how we test whether something is prototypical. An average of all your experiences with something (a summary file that we can use as a shortcut). - Represent "averages" or "ideals" for a category. Example for the category "fruit": - Prototypical examples: apple, banana, orange. - Atypical examples: olive, tomato. What is a node, what does it represent (slides 8-13). A unit in a network model of knowledge representation. - Objects or concepts and the links represent relations between nodes. - Crucial in how we organize, store, and access knowledge in our cognitive systems. Example: In a semantic network, a node for "dog" might be linked to: - An attribute node: "has fur" - A categorical node: "mammal" - Example nodes: "beagle," "poodle" - Related concept nodes: "pet," "friend" The spreading activation and hierarchical network models of semantic memory: what they are, what they predict, and what the evidence is that is consistent with each model (slides 14-25). Spreading Activation Model: concepts in our memory are organized in a network of nodes (representing concepts) connected by links. - When one node is activated, activation spreads to related nodes through the connections, facilitating the retrieval of related information. Predictions: - Activation will spread to connected nodes, allowing for quicker retrieval of related concepts. Evidence: - Semantic priming: people are faster to recognize a word (ex; "nurse) after being exposed to a related word (ex; "doctor"). - Reaction times: experiments indicate that response times for recognizing words are faster for closely related concepts compared to more distantly related concepts. Hierarchical Network Model: organizes concepts in a structured, tree-like format where higher-level nodes represent broader categories, and lower-level nodes represent more specific categories. - Strict categorization. Predictions: - Retrieval times will be longer for nodes that are farther apart in the hierarchy. - Ex; it would take longer to confirm that "canary" is a "bird" than to confirm that a "canary" is a "animal." Evidence: - Sentence Verification Tasks: people take longer to verify relationships between concepts that are farther apart in the hierarchy (ex; verifying "a canary is an animal" takes longer than "a canary is a bird"). - Feature Verification: when asked about features of a concept, people typically retrieve information from the highest relevant node first, which aligns with the hierarchical structure. Cognitive economy, what is it (slide 16). A principle in semantic memory that refers to the organization of knowledge in our minds. - We store information in a way that minimizes redundancy and maximizes efficiency. Schemas, what are they and how do they influence perception/attention/comprehension/memory (slides 29-41). A mental template stored in long term memory, used when we interpret experiences (comprehension). - Perception, comprehension, interpretation, and memory are all mediated by schemata. - Help categorize information, allowing us to quickly make sense of new experiences. Perception: schemas influence how we perceive stimuli. - Help filter sensory information by focusing our attention on what is consistent with our expectations and ignoring what is not. - Ex; a restaurant, we expect to see tables, chairs, and waitstaff (leads us to notice these features more readily and overlook unexpected elements). Attention: schemas guide our attention to relevant information. - Prior activation of a schema can make it easier to attend to information that is consistent with that schema. - Ex; a classroom, a student may focus on the teacher and whiteboard while ignoring unrelated noises or distractions. Comprehension: schemas provide a context for interpreting information. - When encouraging incomplete information, schemas help us fill in gaps. - Ex; understanding a story or a conversation often relies on existing schemas about social interactions or narrative structures. - If we hear a story about a family, we might assume certain details based on our family schema, even if they aren't explicitly mentioned. Memory: schemas influence how we encode information and what we retrieve later. - Information that fits well with an existing schema is often encoded more efficiently and remembered more easily. - Schemas can lead to memory errors; we might remember details that align with our schemas but that were never present. - Ex; recalling seeing something in a scene that fits our expectations but wasn't actually there. Bransford and Johnson's studies regarding how context/knowledge influence comprehension/memory (slide 40). In their experiments, participants were presented with passages of text that describe a scenario. - Some participants received the passages with relevant context provided beforehand, while others did not. Findings: - With context: found it easier to understand and remember information. - Without context: struggled to comprehend it and remembered fewer details. - Memory improvement: those who had context understood and recalled more information later on. - Schema activation: allows individuals to make connections, fill in gaps, and organize new information more efficiently (when people have a framework to place new details, their memory is more robust and coherent). False memory and the DRM paradigm (slides 52-64). False Memory: people remember events or details that did not actually occur or misremember the details of events. - Our memories can be influenced or distorted by various factors. DRM Paradigm: Deese-Roediger-McDermott, widely used technique to study false memory. - Involves presenting participants with a list of related works and then testing their memory of those words afterward. Findings: - High false recall rates (many participants report remembering the related but non-presented word, indicating how easily false memories can occur). - Influence of semantic associations (the paradigm demonstrates that our memories can be influenced by the meaning and associations of words, leading to errors in what we recall. **Levels of Processing/Organization** What is the influence of distributed practice on memory? What about massed practice? (slides 7-13). Distributed Practice: spreading out study sessions, instead of cramming (better for long term memory and understanding). - Better retention (compared to cramming). - Less fatigue (studying in shorter, spaced-out sessions reduced mental fatigue). - Improved understanding (allows for time between sessions to process information). Massed Practice: studying all at once in a short period (like cramming for an exam). - Short-term gains (quick recall in the short term, especially right after studying). - Poor long-term retention (brain doesn't have enough time to consolidate the information effectively). What is maintenance rehearsal and how does it influence memory (slides 16-17). A memory technique that involves repeatedly saying or thinking about information to keep it in short-term memory. - Repetition. Influence: - Keeps information accessible (by repeating the information, you keep it active in your memory for a longer time). - Limited long-term effect (doesn't lead to deeper understanding or strong long-term retention). What are the levels of processing theory, how does level of processing influence memory? (slides 18-25). 1. Deep processing: focusing on the meaning of the information and making connections to other knowledge. - Thinking about how a word relates to your personal experiences or its implications. 2. Shallow processing: physical or sensory aspects of the information (like sound or appearance). - Recognizing. Word by how it looks or sounds without thinking about its meaning. Influence: - A deeper level is more likely to be remembered (better recall). - Deeper processing encourages understanding and integration of new information with existing knowledge, making it easier to retrieve later. What is a deep level of processing and what is a shallow level of processing? (slides 21-25). Deep Level of Processing: engaging with information in a meaningful way. - Requires analyzing and relating the information to existing knowledge, enhancing understanding and memory retention. - Ex; creating a story or visual imagery related to the information. Shallow Level of Processing: a superficial level of engagement with information, focusing on its surface rather than its meaning. - Ex; repeating a word just to memorize it without understanding its meaning. You should know the effects of distinctiveness and organization on memory (slides 33-38). Distinctiveness: distinctive items remembered better (ex; Ford, Chevy, Mazda, **pineapple**, Chrysler, Toyota, Cadillac). - Distinctive items are processed more deeply because they are easier to distinguish from everything else. Organization: organized information is easier to recall, making it easier to learn and remember. - Mental frameworks. Transfer-appropriate processing: what is it and how does it influence memory (slides 40-43). The idea that what is important is not the depth with which you process something, rather the compatibility between encoding and retrieval processes. - Deep semantic processing is not inherently better. Influence: - Effectiveness of encoding depends on the manner in which memory is tested. - Deeper encoding (higher potential memory performance). - Realization of potential depends on compatibility between encoding and retrieval. Encoding specificity: what is it and how does it influence memory (slides 44-50). Principle that memories are more easily retrieved if the context at the time of retrieval matches the context during the encoding (learning) phase. - The way you learn something influences how well you can remember it later. Influence: - Context matters (if you study in the same environment where you take a test, you are more likely to recall the information during the test). - Mood and State (your emotional state when you learn something can also affect recall, if you study when you are happy, you may remember the material better when happy again). - Specific Cues (using specific cues that were present during the learning phase can help trigger memories). **Autobiographical Memory and Emotion** Types of autobiographical memory (slides 4-6). Memories for events and issues related to yourself - Similar to episodic memory. Memories for specific experiences and personal facts of one's life. - Specific experience (buying your first car, single unrepeated event). - Personal fact (do you own a car? / Not image or memory based). - Genetic personal memory (like specific experiences, except that the event is repeated, or a series of similar events occurs/ex; getting married for the 5^th^ time). The reminiscence bump: what is it (slide 8). A phenomenon where people tend to remember more life events from their late teens to early adulthood (16-25) than from other periods of their life. Bartlett's "War of the Ghosts" study how did people's memory change for the source material (slides 9-11). In his study, Bartlett had participants read a Native American folk take called "War of the Ghosts." - After some time, they were asked to recall the story from memory. Findings: - Leveling (making the story simpler). - Sharpening (highlighting and overemphasizing certain details). - Assimilating (changing details to fit one's personal background/knowledge base. Ways of testing autobiographical memory and what each technique entails (slides 13-14). Galton's cuing technique. - Recall a personally related event to a cue word. - Problems: too open-ended. Autobiographical memory schedule (Kopelman, Wilson, & Baddeley). - Ask people about personal info and events from different periods of one's life (usually used to compare memories across time periods). - This is what led to the discovery of the reminiscence bump. The diary entry method (Wagenaar). - Cued to write down what you're doing at various points during the day. - Problems: extremely time-consuming, personally invasive. - Researchers usually use it on themselves. Flashbulb memory: what is it, how accurate is it (slides 15-21). A vivid and detailed recognition of a significant event, often accompanied by strong emotions. - Feel very clear and like a snapshot of the moment when the event occurred (very surprising and emotionally arousing event). - Typically, memories of events of national or international significance (assassination of JFK, MLK, princess Diana's death). Determinants: - High level of surprise. - High level of emotional arousal. - Consequentiality. - More likely to be rehearsed. Criticisms: - Veridicality: cannot take accounts at fake value at being accurate, no matter how confident people sound. Accuracy: most people are highly confident in their memories/very accurate, though studies show that flashbulb memories can still contain inaccuracies or distortions over time. The misinformation effect, what is it (slides 22-26). Post-event misinformation seems to reliably lead to incorrect memories regarding the original source. - Lead to false memories or inaccuracies in recalling what actually happened. - Ex; witness a car accident and later hear something described incorrectly, your memory of the accident might change to include that false detail. - Misinformation acceptance, source confusion. What are the five theories of how emotion and cognition interact (slides 34-43). 1. Network Theory (Bower, 1991). - Extension of semantic networks with a series of "mood/emotion" nodes which interact with other nodes. - Emotions can be linked to concepts in the network. - Mood dependent memory: information better recalled when encoding mood and retrieval mood match (ex; depressed individuals find it difficult to break out of depression because of continuous depressing thoughts). 2. Mood Consistent Schemas. - Like the network idea except that certain moods cue the use of mood consistent schemas which may be invoked later if mood is reinstated. - Schema would summarize feelings/thoughts usually experienced when in a certain mood. - Problem: assumes that multiple schemas can be simultaneously activated (one for internal state, one for external context). 3. Cognitive Resource Theory (Ellis & Ashbrook). - Less capacity remains for cognitive tasks such as memorizing information. - Mood may either alter capacity or lead to task-irrelevant thoughts. - Sad people perform less well than neutral controls. 4. Cognitive Initiative Theory. - Performance deficits when depressed occur because a person is less likely to initiate action when depressed vs not depressed. - If depressed people are forced to process the information (ex; rehearse out loud), then their performance is like non-depressed people. 5. Emotions as signals for processing that is required (Frijda, 1988). - Emotions inform us about the state of the world and whether action is necessary. - Positive = everything is okay = no action; negative = something is wrong = action required. Weapon focus, what is it and how is attention/memory influenced by it (slide 46). When a witness will "zoom-in" on some critical detail, such as a weapon, to the exclusion of other things in the scene. - Emotionally bland vs emotionally arousing narrative. - Emotionally aroused subject show better later recall for details "central" to the story relative to emotionally bland. - Emotionally bland shows better later recall for peripheral/background details relative to emotionally aroused. Emotionally bland subjects had better "overall" recall, suggesting that emotion affected memory by "zooming in on a specific detail of the episode." The nude effect: what causes it, and the typical pattern of memory results associated with it (slides 47-53). Presenting "unexpected" nude pictures during a memory experiment. - Presented a series of black and white line drawings for a later memory test, halfway through, a black and white nude photo is presented for half of all subjects. It suggests that high memory for "nude" and poor memory for subsequent pictures is due to emotion (narrowing of attention to emotional event). - The nude image captures attention due to its emotional and shocking nature, leading to increased focus on other images presented before and after. - The emotional arousal caused by the image can help strengthen the memory for the neutral images. Results: - Enhanced recall (remember more details). - Increased recognition (better at recognizing and recalling the neutral images due to heightened attention and emotional response triggered by the nude photo). The three main elements of repression according to Holmes (slide 59). - Selective forgetting of materials that cause pain. - Not under voluntary control. - Material is not lost but stored in unconscious and can be returned to conscious if anxiety associated with the memory is removed. **Implicit Learning** Implicit memory: what is it, what are its defining characteristics (slides 8-20). A type of long-term memory that helps you remember things without trying to recall them (influences your thoughts and behaviors without being aware of it). - Unconscious recall (ex; riding a bike or tying your shoes). - Memory (skills and tasks you've learned (ex; driving a car, you know how to do this but might not be able to explain how). - Priming (exposure to one stimulus can influence your response to another stimulus later (ex; seeing the word "yellow" might make you quicker to recognize the word "banana"). Implicit learning: what is it, problems with measuring it -- sensitivity and information criterion; slides 21-36). The process of gaining knowledge unconsciously, without being aware of what you are learning. - Happens through exposure and practice rather than through explicit instruction. - Ex; learning the rules of a game by playing it instead of being told the rules. Problems: measuring is tricky due to the difficulty in detecting subtle learning and distinguishing between types of knowledge acquired. - Sensitivity (people may not show clear signs of what they've learned, if a test is not sensitive enough to detect subtle improvements in performance, then it may incorrectly suggest that implicit learning hasn't occurred). - Information Criterion (the challenges of distinguishing between implicit and explicit learning based on the type of information recalled, participants may mix conscious and unconscious knowledge making it hard to know what they learned implicitly). **Guest Lecture 2** Dementia, what is the most common form and what are the causes and risk factors for it (slides 5-11). Alzheimer's disease. Causes: - Genetics (inherited). - Environmental and lifestyle factors (pollutants, heart disease, stroke, diabetes, traumatic brain injury). - Abnormal levels of the protein's amyloid in and around brain cells (form plaques that make it harder for the brain to function). - Decrease in neurotransmitters like acetylcholine. Risk Factors: - Down\'s syndrome (trisomy 21). - Family history. - Chronic high blood pressure. - Head injuries. - Gender. - Smoking and drinking. Multiple sclerosis, what is it and what is it characterized by (slides 24-26). A chronic disease that affects the myelin sheath of neurons in the CNS (affects 2.3M people worldwide, caused by genetic and environmental factors). - Often diagnosed between the ages of 20 and 50 years, with females experiencing it more often than males. - Northern European descent and Whites have a higher risk of developing the disease. What are the different types of amnesia and definitions for each (slides 40-42). Anterograde Amnesia: the inability to form new memories. Retrograde Amnesia: the inability to recall memories. Post-Traumatic Amnesia (PTA): develops after a brain injury (involves both anterograde and retrograde amnesia). Transient Global Amnesia: a short-lived condition that involves both anterograde and retrograde amnesia (lasts less than 24 hours). Dissociative Amnesia: caused by mental health-related issues, such as abuse or traumatic events. Selective Amnesia: where people forget certain parts of their memory or events (sometimes used in psychiatry to help people forget distressing events). Korsakoff's Syndrome: a disease that occurs in people with thiamine deficiency (vitamin B1) or long-term alcoholics (causes both anterograde and retrograde amnesia).