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The Secrets of Learning and
Memory
http://learningandmemory.synthasite.com
Dr Andrew P Mallon
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BRAIN FACTS
• Weighs 3 to 3.5 lbs
• Uses 20% of the body’s energy
• Needs 8 gallons of blood per hour
• Consumes 1/5 of the body’s oxygen
• 10% of the cells are neurons (100 billion)
• 30,000 neurons fit on the head of a pin
• Neurons make 1,000 to 20,000 connections
• Synaptic permutations
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The Nervous System
• Nervous system—distributes and processes information. Central nervous system (CNS)—brain and
spinal cord
Peripheral nervous system (PNS)—nerve fibers that connect CNS to rest of body
• Neurons—nerve fibers, collect and process incoming information.
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The Visible Surface of the Human Brain
© Visuals Unlimited, Ltd.
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How Humans Acquire and Use Episodic and Semantic Memories
• Memory is better for information that relates to prior knowledge (memory in context). In study, participants remembered twice as many
story details if they saw a contextual sketch before hearing the story.
• *Application* Skim a textbook chapter for key points before you read its details.
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If the balloons popped, the sound wouldn’t be able to carry, since everything would be too far away from the correct floor. A closed window would also prevent the sound from carrying, since most buildings tend to be well-insulated. Since the whole operation depends on electricity, a break in the middle of the wire would cause problems. Of course, the fellow could shout, but the human voice is not loud enough to carry that far. An additionalproblem is that a string could break on the instrument. Then there could be no accompaniment to the message. It is clear that the best situation would involve less distance. Then there would be fewer potential problems. With face-to-face contact, the least number of things could go wrong.
Effects of Organization on Memory
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Effects of Organization on Memory
(a) Data from and (b) adapted from Bransford and Johnson, 1972.
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If the balloons popped, the sound wouldn’t be able to carry, since everything would be too far away from the correct floor. A closed window would also prevent the sound from carrying, since most buildings tend to be well-insulated. Since the whole operation depends on electricity, a break in the middle of the wire would cause problems. Of course, the fellow could shout, but the human voice is not loud enough to carry that far. An additionalproblem is that a string could break on the instrument. Then there could be no accompaniment to the message. It is clear that the best situation would involve less distance. Then there would be fewer potential problems. With face-to-face contact, the least number of things could go wrong.
Effects of Organization on Memory
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Effects of Organization on Memory
Aoccdrnig to rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit a porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.
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Deeper Processing at Encoding Improves Recognition Later
• Depth of processing The more meaningfully you analyze information at
encoding, the stronger the retrieval.
FORNIX
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Transfer-Appropriate Processing
• Transfer-appropriate processing—retrieval more likely if cues at encoding and recall are similar. Context may be a factor (e.g., words to words or
images to images).
Depth of processing at encoding helps when retrieval requires deep processing (e.g., requires knowledge of semantic meaning).
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Transfer-Appropriate Processing: Research
• In study, divers studied some words underwater and others on the beach. Words learned underwater were best recalled
underwater.
Words learned on the beach were best recalled on the beach
When learning and recall environments were radically different, recall dropped about 40%.
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Transfer-Appropriate Processing: Research
• But, in another study, college students took final exams in: The same room where the course was taught.
A novel classroom.
• Students’ exam performance was not affected by testing in a new classroom.
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Learning and Memory in Everyday Life— Total Recall! The Truth about
Extraordinary Memorizers
• There is no scientific evidence that photographic memories exist.
• Eidetic imagery is the ability to store visual information. Usually fades
after a few seconds.
Rare Books Division, The New York Public Library, Astor, Lenox, and Tilden Foundations
Copyright AMSP
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Working Memory
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Lower limit
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Average Adult by 12-13 years
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Upper limit
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.
CHUNKING27
HOW DID THEY DO IT?
• Input: ….4 2 0 7 9 9 8 1 0 6 9 3 8….
• 420. “I said a flat mile, a good high school mile”
• 799 “I said 79 was an age, almost 80”
• 810 “And 8:10 was a 2-mile, and I said it was a really fast two mile”
• 6938 “Then this was a 10-mile, it was up there, a really slow 10-mile”.
Emotional Learning and
Memory
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Autonomic Arousal and the Fight-or-Flight Response
• Arousal—bodily responses that prepare to face threat (fight-or-flight response).
• Responses include: Increased blood flow to muscles
Increased respiration
Depressed digestion
Depressed immune function
Fight or Flight Video
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Autonomic Arousal and the Fight-or-Flight Response
• Bodily changes mediated by autonomic nervous system (ANS). Sympathetic division of ANS is switched ON for
activation (especially cardiovascular system).
• ANS sends signal to adrenal glands, which secrete stress hormones, including: Epinephrine (or adrenaline)
Quickly increases heart rate, blood pressure, respiration.
Glucocorticoids (including cortisol)
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The Fight-or-Flight Response
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Which Comes First: The Biological Response, or the Conscious Feeling?
(B) Modern emotional theory = see the bear, jump, interpret the bear as dangerous, then feel fear.
33
Pictures Illustrating Emotional and Neutral Stories
Photos courtesy of Larry Cahill, based on an original design from Heuer and Reisberg, 1990.
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• Result: emotions strengthen explicit memories.
Emotion and Encoding of Memories
Graph of effect of emotion on story recall.
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Emotion and Retrieval of Memories
• Mood-congruency of memory—it is easier to retrieve memories that match our current mood. e.g., patients diagnosed with clinical depression more
likely to recall sad events.
• In study, participants were asked to recall episodic memories elicited by neutral nouns (ship, street, etc.). Participants’ stories reflected their current mood
(happy or sad).
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Mood Congruency of Memory
Data from Eich et al., 1994.
37
Anagram Experiment
38
Learned Helplessness
• Learned helplessness—exposure to uncontrollable punisher teaches expectation that response is ineffectual. Reduces avoidance motivation.
May be component of depression.
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Learned Helplessness
• In Seligman et. al. study: Dog received shock in an avoidance chamber.
If dog heard warning tone before shock, learned to jump barrier to safe chamber, avoiding shock.
Next, dogs learn CS (tone)–US (shock) association before placement in avoidance chamber. Prior US exposure gave some dogs learned helplessness.
Dogs never learned to jump the barrier to escape shock.
Instead, they ran around, then lay down and whimpered, enduring the shock.
40
Learned Helplessness
• A person or animal perceives that they are unable to change a situation, even if the situation is changeable. This feeling of futility is thought to be caused by an individual's perception of events and their perception of a lack of ability to control these events. The state of helplessness is learned after an individual's attempts to correct situations failed, or were perceived to have failed. The feeling of helplessness is often expanded to future encounters with similar situations, or even vastly dissimilar situations.
• Torture, Depression, etc?...
41
Learning by Copying
• Observational learning—learning new behavior from watching another demonstrate the action (also, social learning). Copying = doing what one observes another doing.Video Copying
• In observational learning researchers cannot reliably predict learning outcome. Difficult to predict what is perceived.
Nothing compels observer to copy.
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Learning by Copying
• True imitation—copying that reproduces motor actions.
• Emulation—copying that replicates an outcome (goal) without reproducing the specific motor actions used to achieve the outcome.
43
Bandura and Observational Learning
• Bandura and colleagues (1961): Will preschool children become more aggressive after observing aggressive adults? Adult acted aggressively toward Bobo doll.
Children imitated (modeled) what they saw.
Children were not rewarded for their actions or for their interactions with the Bobo doll.
Thus, similarities in actions did NOT result from instrumental conditioning.
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Scenes from Bandura’s Bobo Doll Experiment
Bandura, A., Ross, D., & Ross, S. A. (1961) Transmission of aggression through imitation of aggressive models, Journal of Abnormal and Social Psychology, 63, 575–582.
45
Bandura and Observational Learning
• In Bandura study, children were provoked; denied toy immediately before test. Children who were NOT provoked (but observed adult
aggression) were less likely to copy.Meaning, in some cases viewing can inhibit, rather
than increase, aggressive behavior.
• Findings: Viewing adult aggression strongly influences child
behavior, even without reward or punishment.
Leaning occurs during observation NOT imitation.
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Social Learning Theory
• Social learning theory—an individual’s past reinforcements will determine how that individual will act in any given situation. Explains learning through observation.
Imitation reveals such learning.
Basic premise = behavior learned without direct reinforcement or punishment.
Acquisition is not the same as performance.
47
Social Learning Theory
• Bandura has identified four basic processes for observational learning: Attention to model.
Retention (memory of observation).
Ability to reproduce.
Motivation (imitation from vicarious reinforcement).Status of model
Similarity to model
Desirability of outcome or goal
Advertising
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Social Transmission of Information
• Social transmission of information— process by which an observer learns from others’ experiences. Books, videos, television, phones, computers,
etc., facilitate transmission of knowledge and culture in complex ways.
Simple forms of information transfer in animals (e.g., rats) provide a model for the basic processes involved.
49
Learning through Social Conformity
• Social Conformity = tendency to adopt the behavior of the group. For example, rats learn food preferences from
smelling a demonstrator rat’s breath.
Fire alarm -20mins
Injured people in crowds
• How might your family or friends influence your preferences?
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Social Transmission of Rats’ Food Preferences
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Learning and Synaptic Plasticity
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The Neuron
Biophoto Associates/Photo Researchers
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The Neuron
• Dendrites—inputs; receive signals.
• Cell body (soma)—integrates dendrite signals.
• Axons—transmit information.
• Glia cells—give functional and structural support to neurons.
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The Synapse: Where Neurons Connect
• Synapse—gap between neurons; pass chemical signals across (neurotransmitters)
• Presynaptic neuron—sending neuron
• Postsynaptic neuron—receiving neuron
• Receptors—molecules specialized to received specific neurotransmitters
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The Synapse
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Synaptic Plasticity
• Synaptic plasticity—ability of synapses to change with experience
• According to Donald Hebb, the connection between two contiguously firing neurons will strengthen.
57
Long-Term Potentiation
• Long-Term Potentiation (LTP)—synaptic transmission is sensitized by recent experience. Occurs in many brain regions of many organisms.
• What is the relationship of LTP to learning? Drugs that block LTP can impair learning.
Rats bred to produce more LTP are better learners.
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Long-Term Potentiation
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How is LTP Implemented in a Neuron?
• Postsynaptic receptors may become more responsive and fire more easily for hours.
• Presynaptic neurons may release more neurotransmitter for hours.
• Postsynaptic neurons may permanently change.
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Long-Term Depression
• Long-Term Depression (LTD)—Neurons that do not fire together become disengaged.
• Possible reasons: Decrease in postsynaptic receptor responsiveness
Decrease in presynaptic neurotransmitter release
Long-term structural changes in neurons and synapses
Memory
CONSTRUCTING IMAGES
DEEP PROCESSINGDeeper processing,
better memory
REHEARSAL Consistent repetition ofinformation over time
ELABORATIONAdds to distinctiveness
ORGANIZATION
ENCODING
ATTENTIONConcentrate and Focus
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Strategies for Improving Memory
• Pay attention
• Make sure you understand
• (Extensive) encoding
• Make associations (old & new)
• Impose organizations
• Involve all senses
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Strategies for Improving Memory
• Practice and distribute learning (spread out practicing over days)
• Over-learn (episodic-semantic)• Get some sleep (no alcohol or caffeine after 7pm)
• Use verbal Mnemonics
• Use visual imagery
• Diet
Strategies for Improving Memory
• Avoid stress• Exercise (increases the formation of new neurons in the hippocampus and better
memory)
• Fasting (ghrelin)
• Routine
• Mental focus (remove distractions)
• Drugs
Experiment fasting
Experiment sleep
n.s.
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Mnemonic Devices
• Mnemonic (from the Greek for “memory”)—memory-improvement technique based on encoding items in a special wayMethod of loci—imagining the different pieces of
information as rooms within a house
Peg-word—rhyming words with position on a list (one in a bun, etc.)
Substitute word—i.e., occipital—ox sip it all
Word associations—i.e., Roy G. Biv, etc.
Principles for Remembering
• It is very important that you have an interest in what you learn.
• Pay attention or you won’t learn anything!
• Organize the information.
• Practice.
Memory Aids/Methods
There are many types of memory aids/
methods that help you remember things, e.g.:
1. Diary
2. Memos
3. Turning numbers into letters
4. Making notes
5. Rote rehearsal.
However, some are effective and some not.
Effective Less Effective
• Extensive recoding
• Link-word method
• Inductive, concept attainment method
• Method of Loci
• Simple rehearsal
• Rote method
• Tutoring & lecturing
Mnemonics
The following slides introduces some
mnemonics for enhancing remembering.
Mnemonics are:
• Techniques for helping us to remember.
• It is the connecting of two ideas, with the second one triggering yet another one, and so on.
• It is based on the idea of making information meaningful by relating it to what you know.
Method of Loci (Places)
Good for remembering events in a particular
order.
1. Construct a sentimental map of your home/
surrounding area.
3. Place the things in these loci.
4. Walk down the street to pick up the things.
5. No more than one item in one place.
6. Places should not be too much alike.
Acronym
• Remember words by forming one word to represent all of the words.
• Word formed on the basis of the first letters.
POLKA
P – pegword
O – organizational scheme
L – loci
K – keyword
A – acronym
Acrostics
• Construct a sentence to remember a sequence of objects.
• First letter of each word represents the first letter of the object.
My Very Educated Mother Just Served Us Nine Pizzas
=
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
Rhymes
Make a rhyme to remember information. E.g.
• Black & Yellow, Kill a Fellow
• Black & Red, Venom Lack
Ridiculous Association/Image Bizarreness
• This method is to remember things by associating objects with bizarre or ridiculous images.
• Association is enhanced if the image is vivid, ridiculous, impossible, or illogical.
• Make the associations interactive, such as
rule of substitution
out-of-proportion rule
rule of exaggeration
• e.g. The dog rode the bicycle down the street.
Imagery Representation
• Good readers respond to text by constructing images of the meanings conveyed by the text.
• This method requires making mental pictures of material.
• No intentional transformation of content is applied here.
e.g. “The king led the elves through the driving rain storm.” – form in your mind the actions and the scene of the sentence.
Memory Strategies
Other than mnemonics, there are memory strategies that are useful for remembering.
The slides below differentiate the strategies into 2 categories:
Elaboration
&
Organization
Memory Strategies
Elaboration
• Note taking
~ construct meaningful paraphrases of important ideas
~ integrate new & old information in personally meaningful way
• Story Grammar
Who is the main character?
Where and when did the story take place?
What did the main characters do?
How did the story end?
How did the main character feel?
• PQ4R
1. Preview. Survey headings.
2. Question. Ask yourself as you read.
3. Read. Read the material.
4. Reflect. Make connections to prior knowledge.
5. Recite. Test your memory of the text.
6. Review. Reread portions you don’t
understand or remember.
• Self-questioning
“How does this information relate to what the author discusses in the preceding section?”
~(synthesis)
“How can this be applied in a scholarly setting?”
~(application)
Organizing
• Classifying /Grouping
girl heart robin purple finger flute blue organ man hawk green lung eagle child piano
green man piano heart eagle
blue girl flute lung hawk
purple child organ finger robin
• Concept Mapping
~ Diagram concepts
relationships
~ Identify important concepts & specify their interrelationship
85
Ghrelin
Hormone released by fasted stomach and travels in the blood stream to the brain
Acts distantly in hippocampus on specific receptorspromotes long-term potentiation higher synaptic density in the CA1 region
ghrelin improved memory performance in a dose-dependent manner. Performance was improved 20–30% at the highest dose, effectively turning C-grade mice into straight-A students
Aged SAMP8 mice—a model for Alzheimer's disease—also showed improved memory performance with ghrelin dosing, and the authors propose ghrelin analogues as potential treatments for memory loss. Of course, over-eating and weight gain would be potential side effects.
memory enhancing drugs
• Companies compete to find ways to improve memoryincrease NMDA/AMPA for LTP
Ghrelin
Amphetamines, (ADHD)
Acetylcholinesterase Inhibitors
Chocolate (dopamine)
• If they discover them, should they be made available to the general public?
• Question: Is taking drugs to improve academic performance (through enhanced memory) any different than taking drugs to improve athletic performance?
Musician
• Speech, language. Memory, attention, IQ and empathy
• After 15months of piano lessons- young children had more highly developed auditory and motor areas.
• Professional musicians have increased grey matter volume. Routing info around the brain (motor, audition & visuo-spatial)
• Start <7yrs… thicker corpus callosum, the bundle of nerve fibres that shunts info between the brain halves.
• Musicians… better auditory memory and attention, children have larger vocab and higher reading ability.
• Increased IQ (early training)
• Better spatial acuity
• Increased plasticity
• Better at language learning
• More empathic… fine tune ability to recognize emotional nuance in speech
Bright Lights
• Light improves cognition and attention
• Bright light during the dayVisual searches
Math
Logical reasoning
Reaction time
• MelanopsinAlertness hormone
Calm Energy Focus Normal
• BLUE light most potentMimics daylight best
• “School Vision” reading speed +35%
Error frequency -45%
• CalmFidgeting -78% in School vision, -10% control
• Blue light also amplifies emotions
• 'normal' setting is for day-to-day classroom activities,
• 'energy' gives an intense blue tint to the light to invigorate pupils when they need to be more active.
• 'Focus', which is an intense whiter light, is designed to help children concentrate during challenging tasks while
• ‘Calm', a warmer red tinted color, makes the room more relaxed and is designed to settle a class towards the end of the day, when disruptive behavior is most frequent
Brain Food
• Omega-3 fatty acidsOily fish, walnuts, green veg.
Little or no effect on memory
• FlavonoidsBlueberries, blackcurrants, cocoa, green tea, red wine.
Improved attention
Protect against neurodegeneration
Raise levels of BDNF, stimulates axon development
Lower BP
Increases blood vessel elasticity
Increase brain blood flowGood for mental performance
Possibly via hippocampal neurogenesis
• Magnesium-L-threonateIncreased Mg in brain
Increased spatial and associative memory in young and old rats
Increases plasticity and neurogenesis
Exercise
• Regular exercise increases brain blood flow… in rats at least
• Monkey…improved memory (hidden food)
Runners had greater blood vessel volume
• Humans… ?Moderate exercise slows age-related decline
Daily walking improved executive functions (planning/abstract thought) in younger adults.
• Exercise=neurogenesis, ↑BDNF and VEGF
• Excessive Exercise= decreased BDNF!
Brain Training Software
• Does NOT work!!
• You only get better at playing games
• 11,000 volunteers in the largest study showed no differences between brain trained vs control subjects.
CN2097
NH
HN
NH
HN
O
O
OH3C OHNH2
NH
HN CO2H
O
OH3C CH3
NH
OHNO
HN
NH
O
O
NH2
O
NH2O
4
4CN2097
OH
H2N
SS
H2N
OH2NOC-Arg-Arg-Arg-Arg-Arg-Arg-Arg
Figure 1. Structure of CN2097.
Ardane Therapeutics
Sub-threshold LTP induction at the Schaffer Collateral-CA1 Synapse rescued by CN 2097.
Using a low intensity 1 second 100Hz (HFS) stimulation train that normally fails to induce LTP (white circles), we added 2uM CN 2097 and were then able to induce a significant LTP (black circles) that lasted for over 60 minutes (data not shown), p<0.05, n=7.
WT
Angelman Syndrome