Psychology: Memory Slides PDF

PSYC1010 M EM O RY ( S P L I T B E T W EE N 2 L EC T UR E S  Memory Put simply: retention of information over time. We don’t possess memories — we ARE memories.  Central to self-concept & ability to function in the world. Increasingly associa...

PSYC1010 M EM O RY ( S P L I T B E T W EE N 2 L EC T UR E S  Memory Put simply: retention of information over time. We don’t possess memories — we ARE memories.  Central to self-concept & ability to function in the world. Increasingly associated with performance markers in academia and the job market.  Paradox of Memory  Our memories are surprisingly good in most situations  e.g., remembering how to get to work.  Our memories are surprisingly bad in others  e.g., names of people we’ve met.  We remember HUGE amounts of information  e.g., lyrics to hundreds of songs  BUT there is huge variability between individuals.  Class Activity  On the next slide, I’m going to present a list of words.  Put down your pens or take your hands off your laptop.  Read the words on the screen, starting with the left column, moving to the middle column, and then finally to the right column.  Don’t read them out loud, and don’t talk to your classmates about them.  Are we ready?  Paradox of Memory  Remembering words that weren’t on the list is the result of a memory illusion  Our brains go beyond the available information to make sense of the world  Representative heuristic  Generally adaptive but makes us prone to errors.  Reconstructive Memory  When remembering, we actively reconstruct memories, rather than passively reproducing them.  Close your eyes and briefly try to remember one of your childhood birthday parties.  Describe your memory of this party.  Did you see yourself as if viewing a photo of it? (observer)  Did you see the world through your own eyes? (field)  Human Memory: Basic Questions  How does information get into memory?  How is information maintained in memory?  How is information pulled back out of memory?  Encoding, storage, and retrieval processes.  Human Memory Computer Analogy NOTE: This analogy is not only imperfect, but it makes memory experts cry or fills them with rage.  Encoding, Storage, Retrieval  Encoding: initial process of recording information in a form usable to memory.  Storage: maintenance of material saved in memory.  If material is not stored adequately, it cannot be recalled later.  Retrieval: Material in memory storage must be located and brought into awareness to be useful.  Encoding  Attention: to encode it, we must first attend to it.  Most events we experience are never encoded in the first place (cognitive misers)  We focus our awareness or select certain input to attend to.  E.g., selective attention and cocktail party effect.  But what about when our attention is divided?  Activity  On the next two slides, I’ll show you words in languages that most or all of you will be unfamiliar with.  I’ll show you the word for 30 seconds and your task is to devise a strategy for remembering it, without writing it down.  Ready? Levels of Processing (Craik and Lockhart) Incoming information processed at different levels:  Deeper processing = longer lasting memory codes Encoding levels:  Structural= shallow  Phonemic = intermediate  Semantic = deep  Enriching Encoding  Elaboration: linking a stimulus to other information at the time of encoding.  Visual imagery: creation of visual images to represent words to be remembered.  Self-referent encoding: Making information personally meaningful.  Memory Storage W H AT I S S T O R E D & F O R H O W L O N G Atkinson & Shiffrin Storage Model  Sensory Memory  First repository for information from world around us.  Each modality has its own form of sensory memory.  e.g., for vision it’s called iconic memory.  Precision high: stores near exact replicas of each stimulus (aka preserved in original sensory form)  Very short duration: approximately ½ second or iconic memory, 2-3 seconds for echoic memory.  If information does not pass from sensory memory into short-term memory, it is lost for good.  Iconic Memory (Sperling)  Participants see a list of 12 letters for 1/20th of a second, asked to recall what they saw  Most could remember 4-5 letters  Then used a tone to signal to them which row to report.  Most reported all letters in that row!  They had access to all 12 letters in their memories, but they fade so quickly that they can’t report them all.  Delay of tone reduced recall. George Sperling (1960) Sensory Memory Studies  Short-Term Memory (STM)  Unlike sensory memory, which is raw sensory stimuli in its original form STM is a memory store in which information first has meaning.  HOW this happens is unclear.  Sensory memory may be translated into graphical representations or images.  Sensory memory may be translated into words.  STM is a detailed, but short-live representation of the information moved from sensory memory.  STM = short in span and duration without rehearsal.  Miller (1956): Magic Number 7 Span of STM in adults is 7 + 2 pieces of information e.g., why phone numbers were originally 7 digits We can extend our STM span by using chunking  A Chunk is a meaningful grouping of stimuli that can be stored as a unit in short-term memory.  Holds information for approximately 15 to 25 seconds organizing information into meaningful groupings NHLPEICBCNBAMLA  Peterson & Peterson STM Studies Gave participants a series of three letters (MKP or ASN) and a 3-digit number to remember.  Some participants waited 3 seconds before recall.  Some participants waited 18 seconds before recall.  Both groups had to count backward in threes while waiting.  After 10-15 seconds, most people did no better than chance. WHY? Peterson and Peterson (1959) STM Memory Studies  Rehearsal  The transfer of material from STM to LTM memory proceeds largely on the basis of rehearsal.  Rehearsal is the repetition of information that has entered short-term memory.  Rehearsal accomplishes 2 things:  As long as the information is repeated, it is maintained in STM.  Rehearsal allows us to transfer the information into LTM (depending on type of rehearsal used)  Rehearsal Maintenance rehearsal: simply repeating the stimuli in the same form (e.g., phone #’s) keeps it in STM, but doesn’t ensure it makes it to LTM. Elaborative rehearsal: when the information is considered and organized in some fashion. e.g., linking it to another memory, turning it into an image, using mnemonics. **Consistent with levels of processing model, elaborative rehearsal creates deeper memory codes is more likely to result in transfer from STM to LTM.  Mnemonics  Formal techniques for organizing information in a way that makes it more likely to be remembered.  Working Memory Debates  Rather than viewing STM as a passive station into which memories arrive and then either fade or are transferred to LTM, some view it as more active.  Modern memory theorists view STM as an information processing system that manages new material gathered from sensory memory and older material pulled from LTM.  In this view STM = working memory.  Working Memory: Central Executive Processor  Setof active, temporary memory stores that actively manipulate and rehearse information to allow us to use the information.  Thought to contain a central executive processor that is involved in reasoning and decision making.  The central executive coordinates 3 distinct storage-and- rehearsal systems: 1. The visual store 2. The verbal store 3. The episodic buffer  Working memory as an active “workspace” Working memory permits us to keep information in an active state briefly so that we can do something with the information.  Long-term Memory (LTM)  Mixture of facts, experiences, and skills that have been coded and filed away for retrieval.  Capacity and duration of LTM is HUGE, perhaps infinite.  Distinction between STM & LTM garnered from research on individuals who sustained damage to their brain and suffer memory loss.  Lab studies confirm this distinction (see next slide)  Long-Term Memory Modules  Memory modules where each of these modules represents a separate memory system in the brain.  Declarative memory = memory for facts: names, faces, dates, etc., which has two subdivisions:  Semantic: general knowledge and facts about the world, as well as memory for the rules of logic that are used to deduce other facts.  Episodic: events that occur in a particular time, place, or context.  Non-Declarative (Procedural) memory = skills and habits, such as riding a bike or hitting a baseball.  Types of Long-Term Memory Knowing what a bicycle Knowing where and Knowing how to ride a bike is is an example of your when you learned to ride is an example of your semantic memory. a bike is an example of procedural memory. your episodic memory.  Oral History and Storytelling: Collective Episodic Memory Indigenous Perspectives  Many Indigenous populations around the world use oral traditions and storytelling to convey history & vital, which can be essential to the survival of the listener and perhaps to the community.  Oral histories also deliver information in a more dynamic nature  When Indigenous storytellers tell a story, they include the use of gestures, sounds, and vocal modulations, as well as the reactions of their audience to convey their story and transport the listener. These memories are stored as episodic rather than semantic memories, which makes them easier to recall, more detailed, and more resistant to being forgotten than other modalities of memories. 35  Oral histories of Indigenous people have, historically, been  Semantic Networks  Mental representations of clusters of interconnected information.  Lines suggest the connections and indicate how the information is organized within memory.  The closer two concepts are together, the greater the strength of the association.  Activating one memory triggers the activation of related memories in a process known as spreading activation.  The Neuroscience of Memory Hippocampus: located in the Limbic system, plays a central role in the consolidation of memories.  Aids in the initial encoding of information, after which the information is sent to the cerebral cortex, where it is stored (as LTM). Amygdala: located in the Limbic The hippocampus and amygdala, parts of the system, involved with memories brain’s limbic system, play a central role in the consolidation of memories. involving emotion (e.g., trauma, phobias). The Biochemistry of Memory  How is the transformation of information into a memory reflected at the level of neurons?  Long-Term Potentiation: certain neural pathways become easily excited while a new response is being learned, while at the same time, changes occur in the number of synapses between neurons as the dendrites branch out to receive messages.  Consolidation: fixation and stabilization of memories in LTM, due to the actions of long-term potentiation. Long-term memories take time to stabilize (this explains why events and other stimuli are not suddenly fixed in memory). Consolidation may continue for days and even years.  The Biochemistry of Memory  Because a stimulus may contain different sensory aspects, visual, auditory, and other areas of the brain may be simultaneously processing information about that stimulus.  Information storage appears to be located in the same areas that initially processed the different sensory inputs.  Thus, memory traces are distributed throughout the brain.  The Role of Sleep  Time spent asleep helps cement newly learned info while time spent awake is hazardous to new info, resulting in accelerated forgetting.  Memory retention benefit from sleep of 20-40%!!  Largely from deep NREM sleep (early in sleep time)  Before sleep, memories being retrieved from STM (hippocampus).  After night of sleep, memories being retrieved from cortex (LTM).  Slow, deep NREM brainwaves act as courier service, transporting memory packets from the hippocampus to the cortex, which future-proofs the memories!  RETRIEVAL GIVE IT BACK!! G E TT I N G I N F O R M AT I O N B A C K O U T O F M E M O RY  Retrieval Cues  Difference between the availability & accessibility of memories.  Retrieval cues = any stimulus (a sound, word, image, etc.) that allows us to recall more easily information that is in already in long-term memory.  Particularly important for recall (e.g., fill-in-the- blank or short answers) vs. recognition (e.g., multiple- choice).  Recall: Levels of Processing  The greater the intensity of its initial processing, the more likely we are to remember it.  Shallow levels: info processed in terms of its physical and sensory aspects.  Memorization of key terms for a test is unlikely to produce long-term recollection of info, because processing is at a shallow level.  Deepest levels: info analyzed in terms of its meaning.  Thinking about the meaning of the terms and reflecting on how they relate to other info that one currently knows is a far more effective route to long-term retention.  Primary, Recency, & von Restorff Effects  Serial position effect: The ability to recall information in a list depends on where in the list an item appears.  Primacy effect: in which items presented early in a list are remembered better.  Recency effect: in which item presented late in a list are remembered best.  Von Restorff effect: more likely to remember items that are odd or distinctive.  Interpreting the Results  Primacy effect: Most people remember the first three words: ball, shoe, and tree, but are less likely to recall the words in the middle.  Recency effect: might have recalled the last three words: cloud, hat, vase, more so than the middle words (but more likely when the list is very short).  Von Restorff effect: did you remember the world xylophone? It’s more likely because it’s distinctive. Visualizing the Serial Position Curve Copyright © 2014 Pearson Canada In  Explicit and Implicit Memory  Explicit memory: intentional or conscious recollection of information.  e.g., trying to remember a definition from your psychology chapter.  Implicit memory: memories of which people are not consciously aware, but that can affect subsequent performance and behaviour.  e.g., Riding a bike, the feeling of vague dislike for an acquaintance, without knowing why we have that feeling.  Priming  Phenomenon in which exposure to a word or concept (called a prime) makes it easier to recall related information later, even when there is no conscious memory of What we encounter can affect our behaviour. the word or concept. If we are asked to fill in the missing letter for the word S_P, seeing a picture of maple trees primes us to see the word as SAP. Yet, seeing a refreshing drink primes us to see the word as SIP.  Flashbulb Memories  Memories of specific, important, or surprising events that are so vivid it is as if they represented a snapshot of the event.  They do not contain every detail of an original scene.  Details recalled in flashbulb memories are often inaccurate.  Forgetting W H E N M E M O RY L A P S E S O R FA I L S U S  Forgetting: A Useful Adaptation?  Is forgetting universally bad? Why or why not?  Imagine that you could go back and erase certain memories that you have, would you? Why or why not?  Forgetting frees up space and reduces competition among memories that is linked to confusion.  Adaptive function depends on what and when we forget!  Ebbinghaus Nonsense Syllables  Used hundreds of nonsense syllables (ZAK, BOL) to test his recollection across varying time intervals.  Found that the most rapid forgetting occurs in the first nine hours after exposure to new material.  The rate of forgetting then slows down and declines very little even after many days have passed. Ebbinghaus Forgetting curve for nonsense syllables  Why Do We Forget?  Failure of encoding: forgetting due to lack of attention.  If information was not placed in memory to start with, there is no way the information can be recalled.  Decay: loss of information in memory through its non-use.  Hypothesis: memory traces, the physical changes that take place in the brain when new material is learned, simply fade away over time.  However, often there is no relationship between how long ago a person was exposed to information and how well that information is recalled.  Interference: information of some memory disrupts the recall of other information.  2 Types of Interference  Proactive interference: interference in which information learned earlier disrupts the recall of newer material.  Retroactive interference: interference in which there is difficulty in the recall of information learned earlier because of later exposure to different material. Both are more likely to occur when the old and new stimuli are very similar. Memory Dysfunctions: Alzheimer’s Disease  Progressive brain disorder that leads to a gradual, irreversible decline in cognitive abilities.  At first, Alzheimer’s symptoms appear as simple forgetfulness of things such as appointments and birthdays.  As disease progresses, memory loss becomes more profound, simple tasks such as using a phone or getting dressed—are forgotten.  Ultimately, people may lose their ability to speak or comprehend language, and physical deterioration sets in, leading to death.  An inherited defect in the production of the protein beta amyloid may be one of several culprits.  Memory Dysfunctions: Afflictions of Forgetting The prevalence and incidence of diagnosed dementia (including Alzheimer’s) among Canadians aged 65 and older (Public Health Agency of Canada, 2017). Prevalence Incidence (%) (Per 1000 Seniors) Age (Years) Male Female Total Male Female Total 65–69 0.8 0.7 0.8 3.0 2.8 2.9 70–74 2.4 2.4 2.4 5.7 5.7 5.7 75–79 5.6 6.1 5.9 13.1 13.3 13.2 80–84 11.4 13.1 12.4 25.6 27.3 26.5 85+ 20.4 26.9 24.6 45.9 53.1 50.4 Total 5.6 8.3 7.1 12.4 15.8 14.4  Memory Dysfunctions: Amnesia  Amnesia is memory loss that occurs without other mental difficulties.  Retrograde amnesia: amnesia in which memory is lost for occurrences prior to a certain event (e.g., injury, illness).  Anterograde amnesia: amnesia in which memory is lost for events that follow an injury/illness.  Information cannot be transferred from STM to LTM, resulting in the inability to remember anything other than what was in LTM prior to the event.  Constructive Processes in Memory  Bartlett argued people remember information in terms of schemas or organized bodies of information stored in memory that bias the way new information is interpreted, stored, recalled.  Our reliance on schemas means that memories often consist of a general reconstructions of previous experiences.  Our reconstructed memories include context, expectations, awareness of motivations of behaviour of others, etc.  This influences the reliability of our memories which in some cases can have profound implications.  Dr. Loftus TED Talk Dr. Loftus TED Talk: https://www.ted.com/talks/elizabeth_loftus_ho w_reliable_is_your_memory?utm_campaign=t edspread&utm_medium=referral&utm_source =tedcomshare  Dr. Elizabeth Loftus: Misinformation Effect  Eyewitnesses are prone to memory-related errors because the wording of questions posed to them by police officers or lawyers can affect the way they recall information. Visualizing the Misinformation Effect (from a different textbook)  Repressed And False Memories  Supporters of the notion of repressed memory suggest that memories may remain hidden, possibly throughout a person’s lifetime, unless they are triggered by current circumstances (ex. during psychological therapy).  Dr. Loftus’s research maintains that some repressed memories may be inaccurate, resulting from a source monitoring error.  Dr. Loftus noted that suggestive forms of psychotherapy and hypnosis, that are more likely to ‘uncover’ these types of memories.  What implications might this have for testimony in court?  Memory in the Courtroom: Eyewitness on Trial  Constructed memoires have led to many cases of mistaken identity and unjustified legal actions due to faulty eyewitness testimony.  300+ prisoners have been acquitted of a crime and released because DNA didn’t match that left behind by perpetrators.  ¾ had been mistakenly identified by eyewitnesses  Eyewitnesses make significant errors when recalling details of criminal activity (even if they are highly confident).  e.g., When a perpetrator displays a weapon it attracts the eyes of the witnesses, causing them to pay less attention to other details.