PSY 368 Human Memory Semantic Memory cont. Reconstructive Memory.
Memory
description
Transcript of Memory
Memory
Cellular and Molecular Basis of Memory Engram
Temporal Types of Memory
Memory
ability
to accept information (encoding)
to store (storage)
to retrieve (retrieval)
information from NS
Memory involves at least four distinct processes:
Encoding - incoming information must be perceived
Consolidation – newly stored information is labile, to make it more stable (expression of genes, structural changes
Storage- to retain over time, almost unlimited capacity
Retrieval – to bring different kinds of information together, it is constructive process, subject to distortion
Consolidation
Retrograde amnesia
A person who has been knocked unconscious selectively loses memory for events that occured before the blow
Retrieval
recall (reproduction) - serial
- free recall
- cued record (with help, hint) (reproduction of paired associations)
Recognition (to recognize again)
•Memory vs learning
Engram (print, foot-mark)
•Memory is not homogeneous •Duration, persistence•Brain structures•Molecular mechanisms
Donald Olding Hebb
*1904 †1985
Canadian psychologist
Hebbian theory:
When an axon of cell A is near enough to excite cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as one of the cells firing B, is increased
Hebb's Law.
"Neurons that fire together wire together."
Eric Richard Kandel
•1929 Vienna
2000 Nobel Prize in Physiology or Medicine
The California sea slug (Aplysia californica) is also commonly called the California sea hare, and this is because the shape of all Aplysia species is reminiscent of the shape of a rabbit or hare. Sea hares are a kind of shell-less sea snail, a marine mollusk
Experimental support for Hebbian learning
Molecular mechanisms
• Posttetanic potentiation (short term potentiation)
Long term potentiation LTP
Posttetanic potentiation
Posttetanic potentiation
Large Ca2+ influx. Saturation of the various Ca2+ buffering systems (ER, mitochondia)
Temporary excess of Ca2+ is called residual Ca2+.
Concentration of free Ca2+
increases the amount of transmitter released
Posttetanic potentiation
A hight rate of stimulation of the presynaptic neuron
A gradual increase in the amplitude of the postsynaptic potential
Postsynaptic potential increases in size = potentiation
Posttetanic potentiation
The enhancement in the strength of the synapse represents storage of information about previous activity
It can lasts minutes but can persist for an hour.
An elementary form of memory
Long term potentiation LTP
NMDA – glutamate receptor
Glutamate
receptors
Long term potentiation LTP
Glutamate synapse
Both NMDA and AMPA receptors
Increase the sensitivity Increase the number of postsynaptic AMPA receptors
Long term potentiation LTP
retrograde messenger (NO)
Long term potentiation LTP
retrograde messenger (nitric oxide)
Postsynaptic part
Presynaptic part
NO initiate an enhancement of transmitter release that contributes to LTP
NMDA redeptor
New synapses
Ca2+ + calmodulin
Transcription - mRNA
Translation - proteins
Long term potentiation LTP
New synapses
Long term potentiation LTP
retrograde messenger NO (enhancement of transmitter release )
Increase in the sensitivity and number of postsynaptic AMPA receptors
Temporal phases of memory
(based on different biological mechanisms)
Iconic (visual) – reflect the activity of sensory buffers, continuation of sensory neural activity
Short-term memories – last for seconds up to a minutes
Long-term memory – weeks, months, years, for the rest of the life of an organism (permanent memory)
Working memory (short-term plus activated long term memory)
A scheme of memory processes that includes encoding, consolidation and retrieval
Iconic (visual) echoic (auditory) – reflects the activity of sensory buffers, continuation of sensory neural activity
Iconic memory (visual persistence, example burning ring)
George Sperling 1960
In Sternberg R.J.: Kognitivní psychologie, Portál, Praha 2002: s. 187.
Experiment: whole-report procedurePresentation 50 msRecall of 3-5 symbols
Iconic (visual)
George Sperling 1960
Experiment: partial-report procedure
Presentation 50 msCued recall – The frequency of
the tone (high, medium, or low) indicated which set of
characters within the display were to be reported Recall of 9 symbols Sperling's original partial report paradigm
Iconic memory is described as a very brief (<1000 ms), pre-categorical, high capacity memory store
Short-term memories
last for seconds up to a minutes
capacity 7 ± 2 items
Verbal memory
AVLT Auditory Verbal Learning Test
Remember folowing words
Verbal memory
AVLT
Who recall word
table
light
bench
pillow
Dick
1. table2. cloud3. bookcase4. tree5. shirt6. cat7. light8. dick9. bench10. chalk11. flower12. bat13. blanket14. soap15. pillow
Verbal memory
Ebinghaus curve
order in series
What is first
What is fresh (last word)
Verbal memory
Better memory for
What concern you personally
Personally interesting
Unusual
Connected with emotions
erotic subtext
Comparison of verbal and visual memory
Explore each picture
Write down names of things
Envelope
Music
Bird
Brush
Palette
Tin
Screwdriver
Telephone
Fireman
Stairs
Dustbin
Bike
Money
Hen
Lettuce
Interactive image
Pacient H.M.
Long term memory
H.M. was taught to trace between two outlines of a star while viewing his hand in a mirror
Regions of the human brain that have been implicated in the formulation of long-term declarative memories.
A lateral view of the brain shows the levels of the transverse sections
Cross sections in two levels
DeclarativeExplicit
Nondeclarative Implicit
EpisodicStore events autobiographical
Semantic
Nonassociative
Associative learning
Long term memory classification
DeclarativeExplicit
Nondeclarative Implicit
EpisodicStore events autobiographical
Semantic
Nonassociative
Associative learning
Long term memory classification
Epizodic-like memory test
DeclarativeExplicit
Nondeclarative Implicit
EpizodicStore events autobiografic
SemanticStore facts
Nonassociative
Associative learning
Long term memory classification
Morris water maze
Temporal lobe lesion
Blue velvet arena
Test: Hidden goal in Blue velvet arena
Alzheimer disease
Control group
Vascular dementia
Mild cognitive impairment
Epizodic-like memory test
DeclarativeExplicit
Nondeclarative Implicit
EpizodicStore events autobiografic
SemanticStore facts
Non-associativeNo relation between two or more stimuli, behavior and its consequence are not related to.
Associative learning
Long term memory classification
Habituation
Sensitization
Imprinting
Long term memorynonassociateve
HabituationAn animal responds less and less strongly to uniform gentle taps on its surface.
Decreas in response to repeated stimulus
Long term memorynonassociateve
SensitizationBy a strong stimulation.A single electrical shock to the skin. Stronger reaction to the weak tap.
Increas in response to repeated stimulus
Long term memory
nonassociateve
Imprinting
Konrad Lorenz
Greylag geese
incubator-hatched geese would imprint on the first suitable moving stimulus
the goslings would imprint on Lorenz himself
Konrad Lorenz
imprinted goslings
Critical period
DeclarativeExplicit
Nondeclarative Implicit
EpizodicStore events autobiografic
SemanticStore facts
Nonassociative
associative learning – relation between stimulus-response two or more stimuli, events,behavior – its consequence
Long term memory
classical conditioning instrumental, operant conditioning (standard or motor learning) conditioned taste aversion priming
Ivan Petrovič Pavlov
Classical conditioning
Sir Charles Scott Sherrington
Classical conditioning
Standard operant conditioning
Edward Lee Thorndike
(1874 - 1949)
Standard operant conditioning
Skinner`s box
Priming
Priming
ABSENT
INCOME
FILLY
DISCUSS
CHEESE
ELEMENT
Priming
Priming
ABS
INC
FIL
DIS
CHE
ELE
Summary
Molecular level, synapses
Posttetanic potentiation Long term potentiation
DeclarativeExplicit
Nondeclarative Implicit
EpisodicStore events autobiographical
Semantic
Nonassociative
Associative learning
Iconic memoryShort term memory
Long term memory classification