PSYC 3334 Chapter 6 Notes

6.1

Memory: a family of processes involved in encoding, storing, and retrieving (EX: recalling or recognizing) information about our experiences in the world

• Short-term memory: info stored for a short duration, which fades after several secs (amount of info stored is very limited)

• Long-term memory: long-term storage of info, which can be stretch back decades

All memory can enable experience to shape thought or behavior

Difference between short and long-term memory

• revealed by trying to recall the items that you remember from memorize words task

• Plotting memory performance according to serial position (U-shaped curve emerge

  • usually better memory for beginning and end of list items (not so much for middle items) AKA Serial position curve

    • when we have better memory for beginning only, it’s called primacy effect

    • when we have better memory for end only, it’s called recency effect

  
  

serial position curve provides quick evidence for distinction between short and long-term memory

• beginning items may benefit from having been encoded into long-term mem

• end items may benefit from still being active in short-term mem

• But middle items benefit from neither and additionally suffer from interference by other items on the list

Short term mem is more easily disrupted by interference

• if recency effect depends on short-term mem → it should vanish when you add an interfering task immediately after the list

  • EX: when distraction task (counting backwards) was added at the end of the list (before participants were asked to recall), ppl did more poorly on later listed items

    • suggest recency effect reflects short-term mem

Long-term memory

• immense capacity, but not always accessing its content and displaying them on the screen

• EX: take photos with friends, saved on phone (encoding)

• EX: pictures need to be maintained (storage), so can access later

• EX: it might take a bit or a lot of searching to find the right pic (retrieval)

Memory failure

• can occur at any of the three stages of encoding, storage, or retrieval

  • Some experiences fail to be encoded properly

  • others may be overwritten during storage

  • sometimes info is in storage, but people fail to find and retrieve it

6.2

Encoding: idea that cues present when a memory was encoded serve as effective prompts to aid in their recall

• process of storing info in long-term memory

• observed from pt called H.M who couldn’t remember new things

H.M. (pt) suffered from severe epileptic seizures in early life

• performed surgery to remove medial temporal lobe structure, including hippocampus

• lost ability to remember new info (EX: can’t tell you what he had for breakfast, and couldn’t name ppl who worked with him over decades)

  • But could demonstrate knowledge acquired before surgery, and was able to pick up some new skills despite of amnesia

H.M revealed importance of brain structure of medial temporal lobe which includes the hippocampus (lobe that plays a central role in memory processing)

• surgery left H.M with anterograde amnesia (inability to form new memories despite retaining old memories

Experiment: showed H.M faces of public figures from before and after surgery

• did poorly on ppl who only became famous after his surgery, but easily recognized ppl who already been famous before his surgery

  • can also recall info from childhood, and recognized ppl he had known before surgery

• He was able to hold info (phone number) for short periods of time, and hold 3 digits in mind for 15 min as long as he kept mentally rehearsing

  • other amnesia pt for long-term mem showed preserved performance in a range of short-term mem tasks → support the distinction between short and long-term mem

Pt with retrograde amnesia (different from H.M) can learn new information but can’t recall info acquired prior to brain damage

• anterograde and retrograde amnesia are doubly dissociable (one deficit can occur without the other) → suggest that ability to learn new info is separate from the ability to recall previously learned info

Anterograde amnesia seems to come from deficit for encoding

• even without amnesia, we don’t remember everything we experience

• we typically only remember experiences that were important to us and therefore we pay more attention to those things

Subsequent memory paradigm: way to study what supports successful memory encoding by separately analyzing items that are subsequently forgotten, hence why people successfully encode some thing and not others

• use fMRI or electroencephalography to collect when participants view a series of items (like words or pictures)

  • given memory test during which they will remember some and forget others

    • researcher then can go back to neural measures collected during encoding and separate them according to whether the stimuli were subsequently remembered or forgotten during the test phase

      • comparing these data reveals how the brain activates differently for items that are later remembered vs those that are forgotten

Many brain regions are more active for items that ppl subsequently remembered → suggest that they are important for memory encoding

• EX: prefrontal cortex, parietal cortex, hippocampal system, and cortical regions specific to the content of the info being encoded (face area of the brain for encoding faces)

  • these same regions are sensitive to how much attention ppl paid during encoding (when ppl are asked to focus more closely on certain info, activity and memory for that material in these encoding-related brain region increases)

EX: picture of landscape overlap with a face

• activity in the brain’s “place area” is higher than when it is attending to faces → causing memory for the landscape to be substantially higher

• there is barely any memory of the actively ignore stimuli

• key to better memory is better attention and focus during encoding

Google effect: phenomenon that occurs when ppl expect to be able to access info on the internet, lowering their own memory for that info

• Experiment: ppl were asked to type trivia statement to computer (half told the search history will be erased and half won’t)

• Result: for ppl who thought the computer was saving the info they typed in, their memory was worse than when they thought the computer was erasing info

  • effect persists even when ppl are explicitly told to remember the info in their heads

  • ppl showed enhanced memory for where to access the relevant info tho

Consolidation: the solidification of connections that enable memory storage

• makes memories more durable and resistant to corruption

• when neuron signals are strong between synapses, signal can travel from one neuron to another more effectively

  • memory is based on the strengthening of connections between neurons (learning and experience strengthens the connections)

Hebb’s rule: a mechanism for strengthening neural connections, often paraphrased as “cells that fire together wire together”

• long-term potentiation (LTP): a principle by which communication across a synapse strengthens future communication between the presynaptic and postsynaptic neurons

  • chemical process that strengthens the synaptic connection between two neurons when both are active (clearing a path for info to travel more freely)

    • more common in hippocampus than in other brain areas, but also enables plasticity throughout other parts of the brain

Feature of consolidation

• slow process bc memory formation don’t happen all at once, but progresses over time even in background when stimulus is not actively perceived or encoded

  • takes time for synapses to be strengthened between individual neurons and for memories to be incorporated info extensive bran network

    • analogy: memory consolidation is like making fresh popsicles in the freezer (memory which are fragile at first, require time to solidify)

consolidation takes time underlies aspects of everyday memory

• can explain interference and distraction effects

  • if mem consolidation were instantaneous, then impact of distraction after encoding should be minimal

    • but studies show that even after an encoding event, distraction can impair memory bc consolidation is ongoing (wet paint that can be smudged)

Progressive nature of consolidation

• explains why trauma to brain (like concussion or drugs) can disrupt memory during consolidation period

  • bc recent memories undergoing consolidation are still fragile, they are susceptible to disruption (retrograde amnesia)

Sleep provides essential time for consolidation to occur, aiding memory recall

• study: the less sleep that first-year students got at beginning of semester (measured with wearable activity trackers), the lower college GPA later in the year

• video games are often used for lab studies of learning: ppl get better with practice as result of memory consolidation

To understand what brain does during sleep

• compare brain activity measured during day (rats while they run around maze in the lab)

• hippocampal cells represent one’s location in environment, operating like neural global positioning system

  • hippocampal activity can be decoded to indicate the position of rat in the maze with high accuracy

    • hippocampal activity of rats during maze-running behavior closely matches their hippocampal activity during sleep

      • suggest that neural connection formed during maze learning were reactivated and strengthened overnight

Daytime naps can also improve learning and overall cog functioning

• Experiment: compared learning of detailed factual knowledge before napping for 1 hour, cramming info further, or taking a break

• result: both cramming and napping led to significantly better memory than taking a break when tested 30 min later

  • after a week, however, nappers showed better long-term mem than crammers

Hippocampal system: the hippocampus and neighboring structures in the medial temporal lobe

• leave pt unable to encode new info into long-term memory while leaving their older memories intact → suggest old memories are not stored in the hippocampal system

Long-term mem are stored in neocortex (outer layers of neurons forming bulk of human brain, supports the initial perception and processing of experience)

• memory in the brain is property of the entire system (not like a computer)

Experiences tend to be multisensory, therefor initially processed in multiple cortical regions (leaves a distributed code)

• distributed code (record): a cortical record of info processing across multiple brain regions, which can be reactivated when remembering the initial experience

  • EX: visual memories are processed in visual areas, and auditory memories are processed and stored in auditory areas. The act of remembering involves reactivating these distributed records within the modality-specific or category-specific brain regions that were engaged during initial encoding

To form new memories and accessible for later retrieval…

• hippocampus and medial temporal lobe (hippocampal sys) initially work together with these specialized regions of the cortex

  • hippocampal sys is active during initial encoding, so damages to its structure result in anterograde amnesia

• in healthy participants, the hippocampus and medial temporal lobe are more active when encountering novel items compared to old items seen before

  • in subsequent memory tasks, they are also more active for items that are successfully encoded compared with items that are later forgotten

Hippocampal sys associates items and their contexts (time, space, characters, etc) across different brain areas: visual info from visual cortex, auditory info from auditory cortex etc

• to link all these disparate parts, the hippocampus binds all the feature together so that activating any one feature can lead to other features to be activated as well

EX: when meeting new college roomate in person

• event is something that you can recall later, with friendly feelings

• area of brain responsive to faces would be active to encode a memory of their face

• area of brain responsive to scenes would be active to perceive room’s layout and etc

• brain needed to associate these two types of info (face and room), forming a richer, integrated memory of this initial greeting

Hippocampal sys indexes (keeps record of) a memory’s different details across different cortical areas that code them

6.3

Memory retrieval

• reactivates the brain regions involved during initial encoding

• details are not stored in dedicated, separate memory vault

  • encoded in multiple distributed areas that were active during initial encoding

Reactivation: for retrieving memories, the phenomenon of exhibiting patterns of brain activity similar to those that occurred during initial encoding

• EX: when thinking of college roommate, face area of the brain will be reactivated in a way similar to when you first met them (also with layout of room for place area region of brain)

• when these two pieces of info are successfully associated, both face and place areas are reactivated together

Experiment: participants were instructed to try to vividly remember the items while brain were being scanned (after learning a set of pictures and sound items)

• Result: when ppl were retrieving memories of picture, their visual cortex was active

• Result: when ppl were retrieving memories of sound items, their auditory cortex was active

  • shows that retrieval of a memory containing sensory info involves reactivation of the same sensory regions that were active during initial perception and encoding of the items

Hippocampus and medial temporal lobe sys are active during retrieval of memories too!

• EX: Hippocampus is the info desk or clerk that can tell you were various items on your shopping list are located throughout the store

Hippocampal system is mainly active when retrieving new memories

• connections in cortical regions are gradually strengthened to a point where cortical memory can be accessed w/o hippocampal involvement

  • EX: after you know a store and where they put things, there is less need to ask the clerk for help → reason why H.M was able to retrieve older memories that were formed prior to removal of hippocampus

    • after some time, memories become encoded so strongly in the cortical regions that the hippocampus is no longer necessary to retrieve the info → memory retrieval involves direct reactivation of the modality-specific or category-specific cortical areas

Supporting evidence

• some pt with damage in nonhippocampal cortical regions (frontal or temporal lobes) shows difficulty recalling episodes from earlier in their life prior to brain damage

  • consistent with idea that memories are stored outside of hippocampus and medial temporal lobe regions

Summary

• when memory is first formed, its encoding and retrieval depend on the hippocampus and medial temporal lobe

  • but once memory is fully consolidated, it can be retrieved directly by reactivating cortical regions

Complementary memory system: a system where hippocampus and medial temporal lobe support rapid learning and the neocortex supports gradual learning

• Hippocampal system (hippocampus + medial temporal lobe) and neocortex

  • two memory system working together to balance both quick learning and stable memory storage

• nature’s solution to learning quickly w/o overwriting old memories

Hippocampal system

• allows for quick learning (even from single experience/exposure)

  • might be desirable for all learning to occur… but actually bad bc it can be chaotic for existing memories if info can be rewritten so quickly → need stability

Neocortex

• learns and changes slowly

• have stability, maintaining the integrity of the circuitry and knowledge

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Neuroimaging’s ability to decode memory reactivation (more precise now)

• using fMRI to distinguish whether ppl are recalling a scene, face, or object

  • able to decode which film clip (richer stimuli) participants are reactivating during recall (from brain activity alone)

Experiment: asked ppl to recognize faces (some where shown before, but some haven’t)

• fMRI could decode whether ppl thought they recognized a face from memory and even how familiar or strong their sense of recognition was

  • But can’t distinguish if the memory was accurate and real → creating false memories

    • ppl claim they recognize a face they never seen before or responded that face is unfamiliar even been shown before

• fMRI can decode what people think but can’t distinguish if item was new or old

  • more work needs to be developed for distinguishing true vs false memories

Frontal cortex: important for memory retrieval?

• studies shown successful retrieval is accompanied by higher left frontal activity

  • in pt studies, frontal lobe lesions cause learning impairments

    • frontal pt show problems in recalling past info and especially in recalling the source of info

      • prefrontal cortex works with hippocampus during both encoding and retrieval

Lateral parietal cortex: involved in memory retrieval

• activity in parietal cortex is higher when an item is successfully retrieved from memory compared to when it is not

  • strength of activation reflects the strength of memory evidence

    • parietal cortex actively represents what is being remembered → differentiating remembered items from forgotten items

Recollection and Familiarity

• recognition involves 2 kinds of subjective experience

  • Familiarity: sense of having seen something or someone before (either can be strong or weak)

  • Recollection: conscious experience of remembering details

Distinction between recollection and familiarity

• using remember/know procedure: an experimental task used to test the distinction between recognition and familiarity

  • Experiment: participants remember list of words/pics and then for each item, they need to judge if they consciously remember having viewed it on the list

    • Maybe items where ppl can’t explicitly recollect studying, but they know were on the list bc of sense of familiarity

Debate of recollection (remember) and familiarity (know) rely on same or different neural mechanisms

• one proposal of hippocampus is important for recollection but not familiarity

  • familiarity is supported by neighboring structures in medial temporal lobe

    • Evidence: event-related potential (ERP) in brain shows different signatures for recollection and familiarity during retrieval

Memory interference

• when retrieval fail when memories compete with each other

  • EX: in serial position curve, ppl have poorer memory for items from middle of list bc they are experiencing interference from items that appeared both before and after them

Experiment: comparing time it takes to recognize various statements that have overlapping elements (… in the park)

• the more examples associated with the statement, the slower ppl are to recognize the statements from memory (aka Fan effect)

  • Fan effect: increased interference when retrieving a memory as the number of other memories with overlapping associations increase

    • shows memory retrieval is dependent on the number of elements associated with the same fact → the more association there are (fan size), the greater the interference

A-B, A-C learning paradigm

• task used to study memory interference

  • EX: memory for a pairing (A & B) is worse when participants also learn an overlapping pairing (A & C) compared to a nonoverlapping pairing (D & E)

Experiment: item A was a cue word (ROSE) and item B and C were images of faces, scenes, or objects

• Learn phase: first learn A-B pairing (ROSE - Taj Mahal)

  • second learn A-C pairing (ROSE - Beyonce)

• Test phase: shown cued word (ROSE - ?)

  • hard bc of proactive interference: phenomenon whereby previously learned material can interfere with subsequent learning

    • memory interference occurs bc word ROSE was associated with 2 images

fMRI can quantify the extend of reactivation

• On interference trials, where ROSE was associated with both scene and face, face-related activity co-occurred with scene activity

  • Result: ppl were worse at recalling Beyonce when there was more scene-related activity → suggest that earlier association with Taj Majal was causing proactive memory interference

    • directly reveals neural evidence for interference effects in memory retrieval

BUT if task was changed to ask ppl to recall first pair rather than second one…

• memory will remain impaired bc of retroactive interference: phenomenon where learning new material can impair memory for older material

  • EX: Memory of ROSE - Taj Mahal will be impaired by something that happened later (ROSE - Beyonce)

    • competition or interference between relevant and irrelevant associations directly influences retrieval difficulty → increasing or decreasing the chance of forgetting

Attentional control: important role in successful retrieval

• relies on intact functioning of prefrontal cortex

  • damage to prefrontal cortex impairs memory retrieval, especially for associative memory tasks that involve interference

    • EX: pt does fine with A-B (initial association) but cause bigger problems for competing association A-C

• Neuroimaging also reveals strong prefrontal activation during memory tasks that involve competition and interference

Retrieval-induced forgetting (retrieval-induced inhibition)

• phenomenon whereby retrieval of target memories causes unselected memories to be lost

Experiment:

• Study phase: participants learn several items from different categories

• Retrieval phase: participants practice retrieving only half of items from a category, cued with word-completion tasks

  • EX: or__, nec__, pine__

• Test phase: all examples from categories are tested

  • probably better at recognizing words like orange, nectarine, and pineapple bc practiced in retrieval phase

But remembering these items makes it harder to remember other items from category (banana. cantaloupe, lemon)

• memories for these inhibited words is even worse than for any words in category of drinks (not practiced during retrieval phase)

  • shows act of retrieving target memories in the fruits category impaired or caused forgetting of other memories in fruits category

6.4

Memory and Emotion

• Flashbulb memories: Vivid memories associated with particularly emotional events

  • Described as unique type of memory, arises for events that involve a high level of surprise and high level of emotional arousal

    • EX: 9/11, when first heard about COVID shutting down

Are these flashbulb memories real?

• some suggested that they are an illusion of confidence rather than a uniquely faithful record of our experience

Evidence: 1986 Challenger Space shuttle disaster (televised live that shocked children across country

• Neisser and Harsch compared answers from children within 24 hours of events and 2.5 years later about how confident they were of their memory

  • revealed ppl remained highly confident in their memory (even tho their recollections 2.5 years later were not accurate)

    • seems like emotional memories may elicit higher confidence in one’s own memory, even tho as vulnerable to decay and error as any other types of memory

New Neisser and Harsch experiment (2001 on 9/11 attack)

• university students reported on how they learned of attack and memory

  • asked students to keep reporting memory again either 1, 6, or 32 weeks later (different than previous experiment)

    • Result: memories of terrorist attack and of a mundane event decayed similarly over time, even though participants reported a high level of confidence and sense of vividness associated with the emotional memory

Evidence from other studies also suggest that despite such vividness and confidence, emotional memories are susceptible to distortion, just as nonemotional memories are

Retrograde memory enhancement: phenomenon where emotional arousal or stress can enhance memory consolidation of material learned just prior

• behavioral and neurobiological research suggest that emotional arousal can strengthen memory

  • learning materials just before emotions are triggered can make it easier to remember

Study: students who watched an emotion-inducing film clip after a classroom lecture performed better on a test 2 weeks later than did students who watched an emotionally neutral clip

Stress hormones can also help solidify memory

• Experiment: rats were administered stress hormones after a training phase → exhibited enhanced memory for their training

  • when stress hormones are blocked (via injections of beta-blockers), their behavior indicated impaired memory compared with rats who got stress hormones w/o beta-blockers

    • shows possibilities for preventing intrusive memories following trauma (like PTSD)

• Experiment: human participants were administered stress hormone epinephrine (like adrenaline) after viewing series of pictures

  • result: ppl freely recalled more items a week later than control group

    • Note: bc stress hormones were injected after learning, their impact can’t be attributed to changes in motivation, emotion, or attention during encoding

      • appeared to affect memory consolidation

Stress can impair memory

• when stressed, it’s harder to encode new info

  • EX: Yerkes-Dodson curve of cognitive performance is impaired under high lvl of stress

• increased glucocorticoids (from stress) can suppress growth of new neurons and cause hippocampus and prefrontal cortex to shrink in size

Study: participants were exposed to stress in the lab

• induce stress by asking ppl to deliver a mock job interview speech and perform mental math in front of panel of judges for 10 min

  • Results: ppl who produced high lvl of cortisol (felt a lot of stress) showed greater memory impairments

Hippocampal atrophy (deterioration)

• feature of many neuropsychiatric disorders like depression and PTSD

  • EX: the longer a pt suffers from depression or combat stress, the smaller the size of their hippocampus

• Stress plays a causal role in damaging and shrinking the hippocampus and leading to cognitive deficits like memory impairment

Emotion-driven memory enhancement play a role in PTSD?

• is it possible to prevent PTSD by administering a beta-blocker soon after a traumatic event?

Study: trauma-exposed pt were given either a dose of beta-blocker or placebo

• assessed 11 and 3 months later in procedure where they listened to audio recordings of scripts describing the traumatic event, and then spent 30 secs imagining that event

  • collected physiological measures of emotional arousal like heart rate, and etc

• shown to differentiate between ppl with and w/o PTSD

  • Result: half pt with placebo showed heightened physiological activity at follow-up, none of pt with beta-blocker had reaction

    • suggests treatment might be effective in preventing PTSD

6.5

How to use memory strategies to study?

• Mnemonists: a person who has trained to perform astonishing feats of memory

  • EX: recite The Odyssey by heart

Dellis - Memory Palance (method of loci)

• imagine walking thur a highly familiar space or spaces of rooms and placing different pieces of info in each room

  • each room later becomes a cue that helps you bring to mind the info placed there

Visualization: assigning novel images to represent aspects of the encoded info

Experiment: compared between memory champs and uni students (control) of memory for both words and nonwords

• presented 100 items with rate of 1 item per 2 secs and make them take a test on the next day

  • Result: champions remembered far more words than control ppl, but they only remembered slightly more nonwords (both groups had better memory for words than nonwords)

    • suggest memory champs may not have elevated memory abilities in general, but instead have improved their memory on specific tasks they have practiced for

      • best mnemonists only report having average memory in their everyday lives (different memory processes)

Memory Strategies

• Metamemory: the understanding of how our own memory works

• Metacognition: ability to monitor and understand one’s own thought process

  • both something that improves over course of childhood development and is one factor that contributes to better memory performance as children mature

Different brain regions activated during memorization

• memory athletes had greater activity in brain regions involved in memory encoding, spatial navigation, and spatial attention (hippocampus, parietal cortex, and retrosplenial cortex

  • consistent with memory athletes setting themselves apart by the strategies they use

Pitfall of familiarity

• students only study until material feels familiar

  • relies too much on familiarity (feeling you have encountered something before, it is not recalling where you search your memory and access info at will)

Effective strategies

• desirable difficulties: strategies that make studying more effortful and slow but improves memory

  • Spacing effect: ppl remember new materials better when they space study sessions apart (Ebbinghaus)

    • retained better memory for material when his study session were distributed over time (distributed practice) compared to massed practice (cram into single session)

      • effective bc memory consolidation plays a role, or that study sessions are spaced apart tend to vary more in their contexts, leading to a richer sampling of the material

• Retrieval practice / testing effect: practicing the retrieval of info, which can aid future recall

  • evidence suggest practicing retrieving info leads to better retention of material than repeated studying

  • testing is useful bc it enables you to gauge your knowledge and it solidifies what you know in the process

  • found effective when accompanied by feedback about what the right answer would have been (like short answered questions)

    • EX: flashcards, brain dumps

Tip-of-the-tongue phenomenon: feeling that the right word is just out of reach

• not being able to bring to mind a word despite of being to recall aspects like number of syllables

  • Blocking: difficulty retrieving memories that are intact and encoded bc of other memories getting in the way

Memory strategies cont.

• Generation effect: enhancement of memory for a list of items a person has generated by one that person was asked to memorize

  • experiment: ppl exhibited better memory for words when they had been asked to complete the fragments than when they had simply read them a second time

    • generating your own review questions is a good study strategy

• Elaboration: memory-encoding strategy of creating connections between pieces of info, including with existing knowledge held in long-term memory

  • memory can be influenced by depth of encoding: the degree where a person encoded superficial vs meaningful info

    • found that deep encoding is linked to better memory

von Restorff effect: effect of better memory for items that are unique within a given list

Self-reference effect: memory-encoding strategy where a person thinks of ways which material might be relevant to them or their interests

• found to improve memory performance even among ppl who have impaired memory as a result of neurological damage

Self-imagining: memory-encoding strategy where a person imagines something from a personal perspective

• Experiment: ppl saw pairs of words (one object and one location)

  • in self-imagining condition, ppl were asked to imagine themselves interacting with object with the paired location

  • then ppl were presented with an object word and had to recall the paired location

    • result: memory was better when ppl had engaged with self-imagining than they were engaging in other elaboration strategies

Strategy cont.

• Chunking: organizing smaller bits of info into larger, meaningful combinations

Hierarchical Organization: arrangement into a meaningful network of association where items are linked to increasingly global categories; can be used strategically to aid memory

• EX: trying to remember names → can list them based on categories like actors, painters, singers, superheroes, book characters

  • creates cues that help to reconstruct the info (like breadcrumbs)

Retrieval cues: clues in the environment or in our stored representations of experiences

• Encoding specificity principle: idea that cues present when a memory was encoded serve as effective prompts to aid in their recall

  • EX: Context-dependent memory - enhancement of memory when the retrieval context is the same as learning context

    • Experiment: asked divers to learn lists of words either underwater or on land

      • result: divers exhibited better memory when their test environment was the same as study environment

State-dependent memory: enhancement of memory when a person’s internal state at retrieval matches their internal state at encoding

• includes mood-dependent memory: phenomenon of exhibiting better memory retrieval for materials learned in the same mood

  • study shown that ppl exhibited better memory for materials they had learned when they were in the same emotional state (happy or sad mood)