PSYC 303 Midterm Study Guide PDF

1 Lecture 1 - Forgetting is a fundamental feature of normal memory – it’s an adaptive mechanism to deal with daily life - Ebbinghaus: memorised lists of three letter consonant-vowel-consonants (CVCs), then retested himself over...

1 Lecture 1 - Forgetting is a fundamental feature of normal memory – it’s an adaptive mechanism to deal with daily life - Ebbinghaus: memorised lists of three letter consonant-vowel-consonants (CVCs), then retested himself over several time periods → forgetting curve: we forget about 50% of material within a day of learning (ie. most significant loss right after learning) - Overlearning slows down forgetting - Longer lists are harder to memorise - Savings score: the amount of info retained or forgotten from an initial learning experience - Borges: wrote about perfect memory in his short story “Funes, the Memorius” – too much memory impairs cognition and basic functioning - Functions of forgetting: 1. Increases well being – less access to painful / traumatic memories 2. Cognitive flexibility requires forgetting useless memories (ie. forget old strategy to work on new) 3. Generalisation depends on forgetting details – only the gist remains - The Von Restorff (isolation) effect: items that are distinct from their surroundings are better remembered - Ex: faces are better remembered when paired w/ distinctive names - Why? - During memory formation, distinct items may attract more attention → processed more during encoding - Unique retrieval cues associated w/ distinct item - Surprising items lead to increase in catecholamines (dopamine, norepinephrine) → boosts memory - Study: - Presented w/ fruit names - Key word was ‘kiwi’ → both fruit and bird - One group told before learning the list that one word is a type of fruit, the other group told it’s a type of bird – control told nothing - Results: memory for ‘kiwi’ enhanced in both groups Techniques to improve memory: - Visual memory: 1. Method of loci: mentally associating items with known spatial locations - Poet Simonides remembered the name of guests based on their location at the table – helped save them - Useful for oral presentations - Used for patients w/ depression to retain positive memories 2. Pegword method: linking (visual) words with numbers  2 - Good for lists of less than 10 - Ex: “one, bun” “ten, hen” - Effective, but difficult – need to memorise peg words too, and problem if the same word is used for different things 3. Visual imagery and names: associate name with person’s prominent feature - Effective in the lab, but difficult IRL because it takes time, and cognitive resources are limited when we meet new people - Verbal mnemonics: 1. Mnemonics: condense info w/ cues to reduce demand on long-term memory - Ex: “ROY G BIV” for the colours of the rainbow 2. Story mnemonic: create story that links info together in the correct order - Ex: there was a ‘sheep’ that lived in a ‘castle’ owned by ‘sailors’ - Very effective (93% recall vs 13% controls) but time consuming and not suitable for everyday life Preparing for Exams: Write summaries of texts Not great For, mental images of the page Re-read info Elaborative interrogations (ie. explain info so that its useful to you) Moderately useful Self-explanation (ie. explain how new info is related to what’s already known) Interleaved practice (ie. reduce interference by studying different kinds of material within one study session) Testing effect: - Learning improves when tested on the material (vs just studying), especially if there is feedback - Size of the testing effect correlates w/ effort given during retrieval (ex. stronger when using free recall, less strong for cued recall, and worse for recognition) - Study: - Memorise text - Repeated study: read text four times w/ no recall Work best - Single test: read three times then recall - Repeated test: read once then recall three times - Memory tested after 5 min and 1 week later - Results: recall higher for repeated test (vs repeated study) by 50% Distributed practice: spaced practice better for long term retention than massed practice - Also better in real-world scenarios - Longer spacing leads to greater retrieval effort  3 - Why does this all work? - Dual memory theory: testing creates an additional memory (vs restudy, which only re-strengthens initial memory) - Testing + retrieval effort + feedback = - Memory formed during study strengthens - Memory for the test is formed (in addition to initial memory), which creates a ‘cue’ memory - Cue memory associated w/ correct response creates a second route to the answer Lecture 2 - Clive Wearing: damage to the medial temporal lobes (incl. hippocampus) - Episodic memory deficit – stuck in a ‘permanent present’ - Henry Molaison (HM): bilateral hippocampectomy to treat epilepsy - Unaffected semantic memory (facts) and procedural memory (motor sequence) Deficits Preserved Episodic memory Knowledge of who he is + his basic life history Severe retrograde (before) + less severe anterograde (after) amnesia Can recognise wife Clive Wearing Stuck in a ‘permanent present’, can Can read music, and play the piano only remember the last 30 seconds Perform explicit memory tests (ex: Pre-amnesia semantic memory (facts) “have you seen this image before?”) Procedural memory (motor sequences) Cannot create new episodic or semantic memories Perform implicit memory tests (ex: Henry Molaison “look at these image fragments – what is (HM) Cannot recall pre-amnesia episodic the image supposed to be?” memory Priming (ex: implicit memory tests) Cannot recognise recent objects or places Conditioning - Note: priming affects perception, conditioning affects behaviour - Modal model of memory: structural model where memory consists of three stores (sensory, STM, and LTM)  4 Types of Memory 1. Sensory memory: - Quick (1 sec) representations of unlimited sensory input – limited by time - Iconic memory: visual memory last a few milliseconds after the physical image disappears – echoic memory (sounds) lasts longer - Study: whole report - Heard a tone, had to report as many letters as possible - Results: capacity of iconic memory is 4-5 items - Study: partial report - Different tones associated w/ different rows - Participants unaware of which tone would play - Results: capacity of iconic memory is 3-4 letters - Masking effect: presentation of a similar but irrelevant stimulus immediately following the presentation of an item impacts item recall - Bright light impairs letter recall performance, but only if it’s presented to the same eye that encoded the letters – suggests encoding in early levels of processing - Pattern masking can happen when stimulus is presented in either eye – must, unfolded later in visual processing 2. Short-term memory: - Temporary storage of small amounts of material over brief delays - Can interact w/ long-term memory - Paivio’s dual coding theory: memory uses two separate channels to store information (visual and verbal), can work together to establish connections between words and images 3. Working memory (Baddley and Hitch): - Related to STM, but WM lasts slightly longer and is involved in the manipulation of information - Includes: - Central executive: involved in attention and higher mental processes (frontal lobe) - Episodic buffer: temporary back-up store for the central executive - Phonological loop: auditory info - Visuo-spatial sketchpad: visual info 4. Long-term memory (Tulving):  5 - Two interacting subsystems: explicit and implicit memory 1. Explicit: consciously retrieved – includes episodic (events, ‘mental time travel’) and semantic (facts, ‘general knowledge’) memory 2. Implicit: accessed w/ out conscious awareness, shown in performance - The memory systems interact: damage to the hippocampus medial temporal lobe (MTL) area causes deficit in the in the formation and recall of episodic memories, and deficit in the formation of semantic memories - Five phases of memory research: - Before scientific method: philosophers (ex: Plato, Aristotle, Locke, etc.) 1. Beginnings: Ebbinghaus, Müller, Pilzecker, Mary Calkins 2. Gestalt psychology: Hedwig von Restorff 3. Behaviourism: Watson and Hull 4. Cognitive psych: Tolman, Bartlett, Baddeley, Tulving, Loftus 5. Cognitive neuroscience: Milner, Tulving, Shacter, Squire, Gazzaniga - Plato: wax tablet (strong impressions linked w/ better memory formation, but can be overwritten or forgotten over time) + bird cage (memorable items are easier to retrieve) - Calkins: beginnings – recency effect - Behaviourism: only what can be directly observed can be studied using the scientific method - Focused on learning (vs memory) - Classical conditioning (connection between stimulus and outcome, Pavlov) vs operant conditioning (connection between behaviour and good or bad outcome) - Bartlett: schema (cognitive framework that helps organise and interpret info) influences what we encode + how our memories change over time (forget unfamiliar, keep what fits schema, substitute unfamiliar w/ familiar) - Study: suppressing unwanted memories so they don’t enter conscious awareness - Learn list of word-picture associations - MRI scanner – told to recall list of words but suppress image - Results: - Frontal lobe activity stronger during image suppression - Hippocampal activity stronger when suppressing images of places (spatial info) - Suppression of memory requires frontal lobe – suppressing unwanted memories is a control (not problem) of retrieval Lecture 3 - Rationalism: knowledge comes from reason and logic - Empiricism: knowledge comes from experience and experimentation → use today  6 - Empirical approach involves observations, data (not facts), and theories - Two ways to test theories: 1. Inductivism: confirmatory approach, making conclusions from generalisations 2. Falsification: for a theory to be considered scientific, it must be able to be tested and proven false - Experimental method: cause and effect relationships – manipulate one variable (the independent variable) to see how it affects the other (the dependent variable) Each participant experiences the same condition Multiple groups, multiple conditions – compare Pros: groups to see differences - Few participants needed - Individual differences eliminated → Pros: dependent variable less influenced by: less measurement errors - Practice / experience effects - Fatigue Cons: - Sequence effects - Fatigue - Practice effects Cons: - Need lots of participants - Variance in population - Internal validity: research questions without bias - Controls, minimise confounds, random assignment, and double blind - External validity: findings can be generalized - How to measure memory? - Recall tests: ask participant to generate a target memory - Free recall, cued recall – free recall is always harder - Recognition tests: does the new item match the old? - Forced choice recognition: which of the following was shown before? - Recognition is always easier than recall - Reaction time - Source memory: recalling the source of learned information - EEG (electroencephalography): electrodes on scalp, good temporal, bad spatial - MEG (magnetoencephalography): magnetic, higher temporal and spatial than EEG - fMRI: magnetic, BOLD – best  7 Lecture 4 - Plasticity shows that the brain is not hardwired – adaptive - Synaptic plasticity (increase in synapses, learning and memory) vs cortical / structural plasticity (rewiring of unused brain area, involves synaptic) - Ramón y Cajal: produced anatomical drawings based on nissl stains – concluded that memories (in the hippocampus) are the result of synaptic changes - Dendritic spine plasticity is essential in memory formation – learning leads to increase in dendritic spines (ie. more connections between neurons) - When we learn, the number of connections between neurons increases - When we learn we experience synaptic sprouting, when these memories stabilise we lose many of these connections (pruning) to fine tune the memories - Long term potentiation (LTP): connections between neurons become stronger w/ frequent activation – how the brain changes in response to experience, learning, and memory - Easiest to induce in the hippocampus - LTP causes glutamate to release, which activates more receptors, leads to stronger depolarisation → and increases likelihood that neuron will fire - Dopamine signals LTP to form – blocking dopamine receptors prevents LTP - Dopamine increases the duration of LTP, which increases change of info being remembered - The ventral tegmental area (VTA) is the major source of dopamine in the hippocampus - Korsakoff syndrome: - Impaired: anterograde amnesia for episodic (event) memory and implicit memory - Unimpaired: semantic memory, normal intelligence, verbal fluidity - Ex: cannot remember being pricked w/ a pin seconds after the event – speculated that the reason for removing hand in pain was because sometimes people have pins in their hands - Dissociations: when brain injury or condition affects one specific brain function, but leaves other functions intact – shows that function is linked w/ specific brain region - Ex: hippocampal damage linked w/ inability to form new declarative memories, but leaves non-declarative memory intact - Double dissociations: better than single – shows that two functions are handled by different brain systems – can be two different patients - Because of dissociation studies, we know know that there is a difference between explicit and implicit memory – and that these types of memory depends on different brain areas  8 - The Papez circuit: a circuit believed to control memory and emotions – composed of the cingulate cortex, entorhinal cortex, parahippocampal gyrus, hippocampus, hypothalamus, and thalamus - Functions as a closed loop; begins and ends with the hippocampus - Hippocampus is required for sensory-processing brain areas to communicate - No hippocampus = no ‘complete’ episodic memory formation - While isolated, these brain areas can form new memories, but they are not ‘complete’ - After the original stimulus is gone, these areas continue to maintain an activity pattern - This theory was later modified and renamed the ‘limbic system’ Lecture 5 - Nativism: innate (ie. genetic) - Empiricism: environment – mind is a blank slate - Interactionism: part innate, part environment – idea supported today - Genotype: the complete set of an organism’s genes. - Phenotype: the overt characteristics of an organism – product of genes and environment - Ex: flamingos are white (genotype) but the pigments in the animals they eat causes their feathers to turn pink (phenotype) - Monozygotic (one, identical) vs dizygotic (two, fraternal) twins - What determines learning success? 1. Total time hypothesis: amount learnt depends on total time spent learning (ex: 10k hour rule, not good) 2. Deliberate practice: identifying weaknesses, and focusing on weaknesses w/ feedback 3. Distributed practice: always better than massed practice - Repetition effect: repeated words better recalled than non-repeated - Lag effect: longer the time between spaced out study sessions, the better performance will be - Reasons why: - Deficient processing: things that seem familiar will be processed less strongly - Encoding variability: learning in different contexts creates different retrieval cues - Study-phase retrieval: lag between retrievals results in more difficult retrieval → strengthens memory - Study phase retrieval is the right theory 4. Retrieval based learning: testing effect → learning is improved when tested on the material, rather than simply studying it - Testing encourages active retrieval of information, which strengthens memory and increases the ability to recall the material in the future  9 - Re-studying things you think you know already is best (don’t just drop them) – even better w/ free recall - Retrieval effort hypothesis: more difficult retrievals are better for memory than less difficult retrievals - Test enhanced learning: process of retrieving items from memory increases their long-term retention - Intrinsic motivation linked w/ better memory - Ventral tegmental area (VTA, dopamine) and nucleus accumbens (NAc) are involved in reward processing and motivation – both increase synaptic plasticity in the hippocampus → lead to better memory - High external rewards linked w/ better memory - Intrinsic and high extrinsic motivation activate the VTA and NAc → leading to better memory - Dividing attention impairs long-term memory formation and impairs task performance - The left VLPFC is responsible for working memory and cognitive control, distraction impairs encoding of new memories in the hippocampus - Study: preservation-consolidation theory - Müller and Pilzecke - Asked to memorise nonsense syllables - Free recall test - Results: participants reiterated the syllables – disruption impaired memory - Preservation consolidation theory: repeating (preserving) items consolidates (solidifies) them into LTM - Sleep increases memory - Sleep dependent triage: sleep enhances emotionally significant memories – others are forgotten - Trace reactivation theory: sleep-dependent replay strengthens memory during slow-wave sleep - Testing is better than just studying - The more difficult the test, the better (ex: free recall) - Feedback increases memory retention dramatically - Delayed feedback is better than immediate - High motivation improves learning - Distractions impair memory - Sleep enhances memory retention  10 - Types of learning: 1. Classical conditioning: - Twitmyer + knee reflect when bell rang - Pavlov w/ salivary reflex in dogs - Requires amygdala, but not hippocampus 2. Priming: - Exposure to a stimulus influences how a person responds to a subsequent, related stimulus - Implicit memory - Perceptual (sensory) priming lasts longer than conceptual (semantic, meaning) for implicit memory – opposite is true for explicit - Priming may reduce simultaneous activation in areas associated w/ the primed items 3. Procedural learning: - Implicit memory - Motor skills and habits acquired through repetition and practice - Basal ganglia and cerebellum - Ribot gradient: brain damage impairs recently formed memories to a greater extent than older memories, implies that it takes time for memories to stabilise - Law of regression: memory decay starts with unstable (ie. newer) memories - Consolidation hypothesis: two types of consolidation (synaptic / cellular + systems consolidation) - Type 1: synaptic consolidation - Occurs within the first few hours after learning – changes at the synapse level (ie. strengthening of connections between neurons) - Hebb’s dual process memory model: neurons form stronger connections through repeated use (ie. “Neurons that fire together, wire together”) - Synaptic plasticity: LTP and learning increase synaptic (dendritic) connections - Type 2: systems consolidation - Takes weeks / years to complete. - Initially, memories are stored in the hippocampus – over time transferred to the neocortex for long-term storage - Hippocampal damage will remove context from fear conditioning, but the fear will remain (amygdala)  11 - Models of systems consolidation: novel info retained in both the hippocampus and cortical regions – overtime hippocampus disengages Lecture 6 - STM holds about 7 ± 2 items - Chunking (Miller): grouping items into one meaningful segment - More likely to confuse similar sounding letters (vs similar looking) – even if presented visually - Phonological (auditory) loop decays quickly, holds 6-7 items - Articulatory rehearsal holds items in memory - Phonological similarity effect: similar sounding words (vs non-similar) impairs recall - Articulatory suppression: interferes w/ the rehearsal process – prevents items from being committed to memory - Word length effect: the longer the word, the more difficult to recall – we remember about as much as we can say in two seconds - Irrelevant sound effect: irrelevant sounds (ex: speech or tones) reduce the accuracy of serial recall (recall items in order) – does not happen w/ background noise (ex: brown noise) - There is a phonological storage unit, w/ a dedicated mechanism to maintain serial order or items – item similarity impacts retrieval from the storage unit - Rehearsal involves item retrieval, and their reinsertion into the phonological store – distraction impairs serial order - Verbal short term memory theories: 1. The feature model: - Assumes that there is only one memory system (ie. STM and LTM are one system) - They are coded as a presence (+1), absence (-1), or lack (0) of features - By itself, a particular feature gives little information about the item, but in conjunction with other features, it represents a whole item - These features represent perceptual and semantic information. Forgetting items in short term memory is the result of interference (feature overwriting), not decay 2. The SIMPLE model: - Memories are stored along a temporal dimension  12 - The retrieval of memories depends on the relative temporal distance between the memory of interest and other memories - Items closer to each other in temporal space can interfere with each other, which can decrease the ability to recall memories 3. Serial Order in a Box (SOB) model: - Memory is represented by neural activity patterns spread throughout the brain. - As more items are added to short term memory, the less distinctive these neural representations become –leading to memory overlap and forgetting - Serial position curve: tendency to remember the first (primacy) and last (recency) items in a list better than those in the middle - First items go to LTM because they are actively rehearsed (primacy effect), while the last items are still held in STM (recency effect) - Recency is remembered more - Longer lists reduce likelihood that item is remembered - As the list increases, so does the number of remembered items - Recency effect disappears when recall is delayed - Recency effect supported by the SIMPLE model - Visuo-spatial STM: saccadic eye movements take snapshots of the visual world – comprised of two forms of memory: 1. Object STM: - Shorter than spatial, less impaired by interference - Limited by number of whole objects, not complexity of objects - Can hold about 4 objects - Does not rely on verbalisation (tested w/ articulatory suppression) 2. Spatial STM: - Lasts 30 seconds, impaired by interference - Complex the filler task linked w/ faster forgetting - Visual STM has a capacity limit of 3-4 items – declines w/ pattern complexity - Uses active rehearsal - Visual objects are those w/ features that are processed through different channels and neuronal areas – to perceive an object as whole, item has to undergo binding process - Binding is automatic and unconscious – not impaired by attention-demanding tasks - Spatial STM can be measured w/ corsi-block test – limited capacity of 4-5 locations - Evidence for separate visual and spatial systems: spatial memory unaffected by visual tasks, and visual memory unaffected by spatial tasks  13 - Double dissociations and separate STM and LTM systems: HM and patient KF (damage to left parieto-occipital region) – complete opposite to HM - Impaired in digit span (STM) and recency in free recall (STM), but spared in primacy effect in free recall and declarative memory END OF MIDTERM 1