Who has good memory?

What are the differences in people's memory ability?

Why are some people so good at certain memory tasks?

Rockies vs. Diamondbacks Colorado 7th inning

Kile flied out to right. Lansing singled to center. E Burks doubled to left, Lansing scored. C Goodwin ran for E Burks. Clint Sodowsky relieved Andy Benes. L Walker singled to right, C Goodwin scored. Bichette singled to right, L Walker to third. V Castilla homered to center, L Walker and Bichette scored Helton walked. N Perez flied out to shallow left center. Manwaring lined out to second. 5 Runs, 5 Hits, 0 Errors (74 words)

After Hill scored, Rodman had his back to the basket when he flipped an over-the-shoulder pass to a cutting Pippen for a layup that restored a five-point lead and more or less ended Detroit's last hope. (98 words)

(101 words)

How much do people differ in memory abilities?

Underwood, Boruch, and , Malmi (1978)

Study of individual differences in memory

200 undergraduates in 10 sessions with 24 memory tests

What is the pattern of correlations between different memory tasks?

Key results:

Implications: we are typically not good at everything and if you are good at one memory task, you might not be good at another.

Studies of expertise and memory:

Ceci & Liker (1986) memory in horse race betters

Memory for musical pieces in musicians

Chi: Children's memory for chess positions

Other studies of Chess:

Studies of chess experts: Degroot (1966)

Bridge, Electronic Circuits

Memory skill makes for faster access, less strain on working memory

Skilled memory theory (Chase & Ericsson, 1982)

Exceptional feats of memory are not due to innate, neurological differences between people. Instead they are due to having sufficient practice and motivation.

1) Information must be encoded in a meaningful manner using previous knowledge to form associations

2) During encoding it is necessary to attach specific retrieval cues to the material so that it can be accessed from LTM by using the cues

3) Extensive practice increases the speed of encoding and retreival operations

Skilled memory results in encoding so that information in LTM is used in a way similar to that of STM.

Individuals with extraordinary memory abilities

Mnemonists: people who use mnenomic techniques

Studied by Luria (1968) Mind of a mnemonist

Explanations for S's performance:

1) Possible eidetic memory

2) Synesthesia: Sensory experiences in one modality evoke sensory experiences in other modalities

3) Used method of Loci

• Walking the streets of Moscow

• Recall errors due to not noticing items on his "walks"

Digit span of 17

Not affected by Brown-Peterson distractor task

Very high retention of stories

Explanations for V.P.'s performance

Creating a mnemonist: S. F. (Chase & Ericsson, 1981, 1982)

Practice on memory span tasks over 2 years

1 hour/day 3-5 days/week

Procedure:

Explanation for S.F.'s performance

Replications of study on S.F.

31,811 digits of pi for Guinness book of world records

Working on 40K digits of pi

Phone numbers

6X6 number matrices

No transfer to other abilities, memory

Explanations for Rajan's peformance

Persons of generally low intelligence with some remarkable skill

Autism:

Savants are not as common in retarded individuals as in autistic individuals

Explanations

1) Damage to left hemisphere leads to compensatory development of right hemisphere (music, art skills, mechanical ability) (Brink, 1980)

2) Abnormalities in hippocampus and amygdala affecting ability to do memory consolidation (Mauman & Kemper, 1985)

3) Skilled memory theory Ericsson and Faivre (1988)

Savants are experts in their area of interest

(just like us)

Some people can maintain an image in memory as if it is in front of them

2-15 percent of School-aged children

Verbalizing while viewing image interferes with memory

(this suggests why adults do not have the ability)

One case of extraordinary adult eidetic imagery

Elizabeth

Excellent recall of images

Could see two pictures of random dot stereogram separated by 10 secs and superimpose them to get image.

Internal strategies/methods to help encode, store, retrieve information

Techniques can be visual or verbal

Techniques that are naturally used without formal training

Techniques that must be learned

• Method of loci

• Peg-word system

One is a gun, two is a shoe, three is a tree

four is a door, five is a hive, six is sticks

seven is heaven eight is a gate nine is a line,

ten is a hen

• Number-letter mnemonic

1142=tight run

13564=team lasher

939-8323 =??

646-1980 =??

Although these technical approaches can help improve your memory:

Link english word with foreigh word in an interacting image

Knuckles for months with 31 days

Memorize 12 numbers for first sunday of each month

1998 = 4 1 1 5 3 7 5 2 6 4 1 6

What day of the week is January 8th?

What day of the week is August 24th?

What day of the week is Christmas?

External memory plays a major role in our daily lives

• What are some things that we use for external memory?
• What are some pieces of information that we store externally?

Why do we need external memory?

When do we need to use it?

What are the problems with external memory?

• Ribbon around the finger
• Writing on your hand
• Friends (remind me to call Jeff when I get home)
• Notebooks, calendars, shopping lists…

A product designed to help a person with memory tasks

Types of memory aids:

Memory Prosthetic: Facilitates memory performance

• Automatic pillboxes

Memory corrector: Corrects potential memory errors

• Creditcard holder that beeps if you don’t return card

Memory Robot: Device that performs memory task for user

• Phone autodialer

Alarm clocks, timers: Big success

Devices to help you find your remote control or keys

Major problem with commercial memory aids is that using them can often be hard than the actual memory task. (Programming a VCR)

External Knowledge Sources

Dictionaries, Encyclopedia, phonebooks, files, computers

What are the problems with external knowledge sources?

• You have to bring them with you.
• You have to know how to use them

• You have to locate the information in them

Lesions

What are the biological processes involved in forming/retrieving memories

Primary questions: How and Where are memories stored?

Searching for the Engram: A memory trace present in the brain after something has been learned

How localized are memories?

• Are they stored in an individual neuron?
• Are they stored in a local portion of the brain?
• Are they stored distributed across the brain?

Karl Lashley (1929): Locating memories.

Train rats to navigate maze. After 10 perfect trials, destroy parts of brain, test whether it can run maze.

Why didn’t he find the location of memories?

Rat had learned many memories (kinesthetic cues (position of body), proprioceptive (where we are in relationship to our body), olfactory cues.

Neurons are nerve cells.

Dendrites: receive information

Axons pass information on to other neurons or to muscles or glands

Myelin sheath: insulates axons, speeds impulses

Information flows from Cell body down to axon

Neuron receives signals on dendrites and cell body

signals can be inhibitory or excitatory

If excitatory - inhibitory signals are greater than a threshold, then the neuron fires.

80% of the weight

Highly interconnected set of neurons (1 neuron connected to 1000s of others)

Made up of folds, actually large sheets of neurons, folded up. More surface area that way

Studies in 60s and 70s. Feed planaria other planaria who have been trained to respond to light.

Showed learning, but failed to replicate.

Raise rats in impoverished vs. rich environments

Rats in enriched environments have:

• Thicker cerebral cortex
• Larger blood supply to brain
• Increased number of synaptic connections (branching dendrites)
• Increased number of glial cells (for metabolic activities of neurons)

Habituation and Sensitization in the Aplysia

Aplysia: ~20,000 large neurons

Gill reflex to touch of siphon.

Habituation: Decrease in gill reflex with repeated presentations

Sensitization: Increase in gill reflex with electric shock

Findings:

• Habituation; Decrease in neurotransmitters released
• Sensitization: Increase in neurotransmitters released

Electrical stimulation of nerve pathways can lead to increases in excitatory presynaptic and postsynaptic potentials.

Long Term Potentiation: Neurons that receive stimulation tend to give bigger responses the next time they are stimulated.

Changes in strength of pre and post-synaptic connections

Evidence for learning: If a pathway is used, it tends to be strengthened

Stage 1: Stimuli causes cell assemblies (groups of interconnected neurons) to set into motion a reverberating electrical signal. (like STM)

Stage 2: If reverberations continue for long enough, anatomical changes in neurons and synaptic connections result in stronger connections (like through LTP)

Disruptions of memory is primarily vulnerable during the first stage

How is memory transferred from STM to LTM?

Memory in transition from STM to LTM is susceptible to disruption

Consolidation theory of memory: information is gradually, and under only under certain circumstances, placed into LTM.

Evidence: Retrograde amnesia:

Loss of memory for events occurring prior to the onset of a disturbance causing amnesia

Information that occurred immediately preceding blows to the head tend not to be consolidated.

Trauma interferes with neural activity that permits consolidation of information in STM or in LTM that is still being consolidated

Often doesn’t affect memories occurring much earlier before trauma.

Inducing amnesia to test Consolidation theory

Electroconvulsive shock (ECS)

Chorover & Schiller (1965)

Rats attached to wires that could induce ECS

Conditioned rats to do a passive avoidance task

Varied time between footshock and ECS

• Amnesia if ECS given .5 secs after footshock
• Some amnesia if ECS given after 10 secs
• No amnesia if ECS given after 30 secs.

Implications: Consolidation process can be interrupted disrupting formation of memories.

It is still not clear exactly how long consolidation takes to happen.

Arousal and Memory Consolidation

The arousal hypothesis: The amount of memory consolidation is related to the degree of neural activity in the brain following learning

ECS has less effect on amnesia on rats given electrical stimulation to the hippocampus, reticular formation, and amygdala.

But,:

• Stimulation must be given immediately during consolidation process.
• Too much stimulation doesn’t help

How do drugs affect memory?

Many factors in a drug that can have a facilitory or inhibiting effect.

Remember drug-dependent memory?

Some drugs:

Psychoactive Drugs: Benzodiazepines (BZs)

Valium, Librium: For panic disorder, anxiety, tension etc.

BZs impair memory ability affecting encoding of information into STM/LTM

Why?

• Sedative effect on central nervous system reduces arousal
• Also disrupts encoding ability

Acetylcholine used for forming memories: Increases in ACH can enhance or reduce memory ability

Scopolamine: disrupts active processing of information

Norepinephrine: Can enhance memory in proper doses when administered directly after learning

Conclusions: Acetylcholine and norepinephrine increase neural activity: Evidence for arousal affecting memory.

Stimulants: Amphetamines can enhance memory when:

• Given right after learning
• Given at the proper level
• Too much reduces learning

Glucose:

Elderly given either sugar or saccharin sweetened lemonade.

Tested for memory:

Sugar group had better memory

Other evidence:

Poor memory in elderly related to poor regulation of blood glucose.

Rats learn better with sugar

Glucose enhances level of activity in the brain.

Does consolidation occur when we sleep?

Recall of material is worse when REM sleep is disrupted

REM sleep occurs most with infants, least with elderly.

Where does consolidation occur in the brain?

Medial temporal regions: Hippocampus, amygdala

Diencephalon region: Mammilary bodies, dorsomedial thalamic nuclei

Declarative knowledge (facts, information): seems to be affected by consolidation

Are these areas where LTM and STM for declarative information is stored? No

These areas are used for processing information into LTM.

LTM information is stored in cerebral cortex

How do we know that declarative and non-declarative memories are stored differently?

• Amnesia typically affects declarative information but not non-declarative information.
• Non-declarative information is likely stored in cerebellum.

Why does consolidation take time to occur?

What would life be like if it occurred instantaneously?

Memory Disorders

Some common memory anomalies

Feeling of having already experienced a situation

Most common among people who have propensity to daydream or are in heightened anxiety, sensitivity or fatigued state.

Why does it occur?

Good and bad Theories

• Saw it in a previous life (Reincarnation)
• Psychic phenomena
• Partial recognition: Current information partially resembles information seen previously.

Lack of recognition of something highly familiar.

Explanation: Seeing something when the re are no or different contextual cues

Lack of recall of items from a particular gap of time, typically after doing a monotonous task

Organic: based on physiological impairment

Psychological: Based on dissociation of memory

Non-organic Disorders: Dissociative Memory Disorders

Can be due to personality change

Stressful or anxiety provoking event causes loss of recall of important personal information.

Loss of information going back years to whole life.

Examples: rape, killing, accidents

Some abilities from past remain.

Amnesic episode can last for days to years

Recover can occur with recall of missing information

Key characteristic: Amnesic is aware that information is missing from life.

Psychogenic Fugue

Like psychogenic amnesia, however person moves from home and assumes new identity

(can remarry, get new friends, take on different personality)

Person does not seem to be concerned about past

Can recover prior life, although often not completely.

Multiple Personality Disorder

Dissociative disorder where multiple personalities are present

Evidence for multiple identities, each with different memories

However, very rare. Mostly found in U.S.

May be a cultural phenomenon.

Organic Disorders

How do we know if a disorder is organic or not?

• Evidence of physical trauma
• Dissociative disorders typically result only in loss of personal past experiences.
• People with Dissociative disorders often have some/all recover of memories.

Assessment tools, some disorders may be both.

What causes Organic Memory Disorders?

• Damage due to:
• Head injuries
• Drugs,
• Disruption of blood supply to brain (injuries or disease)
• Viral/Bacterial Infections
• Illnesses which produce dementia (Alzheimer’s disease)

Recovery from comas there is typically some Retrograde Amnesia (RA)

RA decreases with recovery, although there may always be some loss of memory

Anterograde Amnesia (AA) after injury:

Problem with transferring information into LTM.

Classic Amnesia Syndrome

RA and AA episodes following a loss of consciousness

Due to bilateral damage to brain (typically medial temporal lobes, hippocampus, amygdala)

The case of H.M.: Removal of medial temporal lobes to treat epilepsy

Slight RA, but severe AA

Looses track of conversation

Couldn’t remember new house

Still believes his parents are alive

Has some limited recall of important events (Kennedy assassination)

Mirror tracing

Word stem completion STA --à STAPLE

What information is preserved in classic Amnesia?

• Some RA that diminishes with time
• Profound AA
• Learning of perceptual-motor skills
• Loss of ability to consolidate declarative knowledge (facts, episodes that are consciously available. (Explicit memory)
• Still have ability to consolidate non-declarative information (priming, learning procedural tasks through repetition) (Implicit memory)

RA and AA that lasts a few minutes, hours or days

Can be due to many factors, trauma, stress, sexual intercourse, drugs

Could be due to temporary lack of blood-flow to regions of the brain.

Due to injury to specific brain areas

Aphasia: Difficulty expressing/understanding language

• Broca’s aphasia: Inability to articulate words and speak grammatically
• Wernicke’s aphasia: Good articulation, grammar, but inability to convey meaning.

Apraxia: Inability to perform purposeful movements

• Dressing apraxia: damage to right hemisphere results in loss of movements for dressing

Prospagnosia: Damage to both hemispheres resulting in loss of ability to recognize familiar faces.

Discovered by Sergei Korsakoff (1887)

Symptoms:

• Severe Anterograde amnesia, some Retrograde amnesia
• Flat affect
• Lack of insight into own memory processes
• Confabulation

Cause: Damage to many portions of brain (dorsalthalamic nuclei, mammillary bodies, frontal lobes)

Cause due to: Thiamine deficiency, alcohol

(alcoholics tend to have poor vitamin intake and interferes with intestinal absorption of thiamine)

Dementia

Symptoms:

• Deterioration of intellectual abilities (memory, concentration, judgement)
• Change in personality
• Mood disturbances

Primary undifferentiated dementia: Progressive impairment of the brain (changes to brain tissue) with eventual death

Most common type: Alzheimer’s disease:

Onset of cognitive and behavioral symptoms

Symptoms start off small , so easy to rationalize

Distinguishing features:

• Senile plaques and neurofibrillary tangles in cortex and hippocampus
• Decrease in production of acetylcholine
• Forgetfulness
• Difficulty finding the correct words
• Progressive worsening
• Death within 6-12 years of onset

Cause of AD: ??

Viral, amount of aluminum exposure, hereditary?

Treatment: ??