7/28/2019 Physiologi Learn
1/46
Psikologi
Pembelajaran
7/28/2019 Physiologi Learn
2/46
How is your brain like(?)
A cabbage
A raisin
A pillowcase A grapefruit
String cheese
A walnut
7/28/2019 Physiologi Learn
3/46
Otak Kita
Are like a jungle- nothing runs
the jungle
All parts of the brain participate
with each other, while each hasits own function
There is natural pruning or neural
pruning that occurs when parts are not used (this
may be why sounds not heard or used atrophyover time)
LEARNING IS A DELICATE, BUT IS APOWERFUL DIALOGUE BETWEEN GENETICSAND THE ENVIRONMENT Robert Sylwester, ACelebration of Neuro ns
7/28/2019 Physiologi Learn
4/46
Brains Complexity
Cellular level - three pints of liquid, three
pounds of mass, tens of billions of nerve
cells (or neurons), ten times more
numerous glial cells that support, insulateand nourish the neurons
Brain cells - 30 thousand neurons (300,000
glial cells) fit into the space of a pinhead.
7/28/2019 Physiologi Learn
5/46
Bagian bagian dari Otak
Brainstem (survival )
Cerebellum ( autonomic nervous system)
Limbic system (emotion) Cortex ( reason/logic)
Brainstem
Cerebellum
Cortex
7/28/2019 Physiologi Learn
6/46
Frontal lobe - Cortex
Creativity - Judgment - Optimism - Context
Planning - Problem solving - Pattern
making Upper temporal lobe - Wernickes Area
Comprehension - Relevancy - Link to past(experience) - Hearing - Memory - Meaning
Lower frontal lobe - Cortex Speaking/language - Brocas area
Occipital lobe - Spatial order
Visual processing - Patterns - Discovery
Parietal lobe Motor - Primary Sensory Area - Insights -
Language functions
Cerebellum
Motor/motion - Novelty learning - cognition -balance - posture
7/28/2019 Physiologi Learn
7/46
Brocas
area
Pars
opercularis
Motor cortex Somatosensory cortex
Sensory associative
cortex
Primary
Auditory cortex
Wernickesarea
Visual associative
cortex
Visual
cortex
Language and Thought
Grammar
and word
production
Movement and joint positions
Cerebellum
7/28/2019 Physiologi Learn
8/46
Neurons
Connect to other neurons,
to muscles, or glands
Send and receive chemical information
(messages) for behaviors
Can be a millimeter in length or as long as
a meter Cells nucleus contains DNA (As long a
meter)
7/28/2019 Physiologi Learn
9/46
7/28/2019 Physiologi Learn
10/46
Neurons contain tubular extensions that aredesigned to communicate quickly withspecific cells in the body network - this is a
transportation system, much like a phonesystem.
The brain has both nerve cells and glialcells. The neurons are cellular agents ofcognition; the glial cells act as a scaffoldingor insulation for impulses. (The insulationincreases the speed of the neural (electrical)
messages.)
7/28/2019 Physiologi Learn
11/46
Memory
Place to store information, as in: How muchmemory does your hard drive have?
Information that gets stored, as in: I have fondmemories of my summer vacation.
retention of learned information
Learning: acquisition of knowledge/information
7/28/2019 Physiologi Learn
12/46
Memory
Thompson
many structures involved in memory formation;
memory depends on many mechanisms;
classical conditioning of eyelid responses in rabbit
response occurs in cerebellum - lateral
interpositus nucleus (LIP)
7/28/2019 Physiologi Learn
13/46
The Modal Model of Human
Memory
7/28/2019 Physiologi Learn
14/46
Memory stores
Sensory MemoryShort-Term
Memory
Long-Term
Memory
Capacity Very large 72 items Infinite
DurationVery short (Fraction
of second)
Short (Fraction
of minute)Indefinite
Format(Coding)
Direct
representation ofsensual experience
as action potentials
Spokenlanguage format
Semantic(meaningful)
format
7/28/2019 Physiologi Learn
15/46
Processes
Attention
Selects portion of Sensory Memory for further
processing by STM
Ex: Attend to lecture, not sound of ventilation system.
Chunking
Group items into meaningful units
Strategy to increase capacity of STMEx: 270-348-8-0-8-0
Rehearsal
Repeat information until no longer needed.
Strategy to increase duration of STM
Ex: 8080 8080 8080Oops, what was that
number?
EncodingInformation moved from STM to LTM.
Ex: Studying to learn the answers to the test questions.
Retrieval
Information moved from LTM to STM
Ex: Remembering the answer to the question so that
you can write it down.
7/28/2019 Physiologi Learn
16/46
Four Theories of Forgetting
from Long-Term Memory
Explanation Description Example
Encoding
Failure
Information never
encoded fromSTM to LTM.
Student studies for exam
while
watching TV, cant rememberanswers to test questions.
Decay
Information encoded in
LTM, but decays over time
with lack of use.
However, some memories
never decay, even though
they are not frequently
used.
Decay can be explained
by interference.
Ebbinghaus memorized
nonsense
words, tested his memory of
these days later, found
forgetting curve.
7/28/2019 Physiologi Learn
17/46
Four Theories of Forgetting (contd)
Explanatio
nDescription Example
Interference
Information encoded in
LTM, but cannot be
retrieved because newer
information interferes.
Can be thought of as
retrieval error.Accounts for
Ebbinghauss findings,
without memories
decaying.
Cant remember old phone
number; recall new number
instead.
RepressionAccording to Freud,
painful memories can be
pushed below level of
consciousness.
Very controversial topic;
many psychologists now
argue that repression doesnot occur.
Memories of child abuse
suddenly recalled during
psychotherapy (But are they
accurate?)
Recovered Memory
Syndrome false memories
planted during hypnosis or drugtherapy.
7/28/2019 Physiologi Learn
18/46
Types of LTM
7/28/2019 Physiologi Learn
19/46
Memory and learning
Types of memory:
declarative
facts and events
conscious recollection easy come easy go
procedural
learning to play an instrument, to ride a bike; no conscious recollection (usually);
need repetition or training;
longer retention
7/28/2019 Physiologi Learn
20/46
Memory and learning
Subtypes of declarative memory:
short-termmemory
temporary,
limited capacity,
needs rehearsal (e.g. telephone number)
long-term memory
'permanent' greater capacity
no continual rehearsal needed
7/28/2019 Physiologi Learn
21/46
7/28/2019 Physiologi Learn
22/46
Theories of memory storage
Engram
Engram was a hypothetical structure or
feature inside of the neuron that stored
information
Grandmother cell the neuron that fired
when you see your grandmother
In computers, information (memories) storedin cells or slots of hard drive
But this is not how the nervous system
stores information!
7/28/2019 Physiologi Learn
23/46
Theories of memory storage
Long-Term Potentiation (LTP) Recent research indicates that memories are
stored in the synapses between neurons
Learning involves formation and modification of
synapses Neurons that fire together wire together
LTP takes days to complete learning spaced
over several days more effective at inducing LTP
than learning crammed into short period of time Most research on LTP done on sea slugAplysia
7/28/2019 Physiologi Learn
24/46
Memory and learning
Plasticity paradigms:
Associative mechanisms:
classical conditioning
pairing of 2 stimuli changes the response to one of them
(Pavlov) conditioned stimulus (CS) - originally neutral (no
response)
unconditioned stimulus (UCS) - automatically evokesresponse unconditioned response (UCR)
after repetitive pairing of CS and UCS presentation ofCS evokes learned response - conditioned response
(CR)
operant conditioning - reinforcement and punishment
7/28/2019 Physiologi Learn
25/46
Memory and learning
Nonassociative mechanisms:
habituation
decrease in response to a repeated stimulus not
accompanied by changes in other stimuli
sensitisation
an increase in response to a moderate stimuli as a
result of a previous exposure to a strong stimulus
7/28/2019 Physiologi Learn
26/46
Memory and learning
memory consolidation - storing knowledge
in the long-term memory
Hebb - reverberating circuit - prolonged
excitation leads to chemical or structural changes
Memory of meaningful or emotional facts
enhanced
involvement of amygdala (stimulation ofhippocampus and cortex)
damage to amygdala impairs emotional
enhancement of memories
7/28/2019 Physiologi Learn
27/46
Memory and learning
working memory - modification of the
concept of short term memory
memory consolidation may take place with or
without use of the short-term memory
a phonological loop a visuo-spatial sketchpad
the central executive - directs attention towards
stimuli; determines what will be stored in the
working memory
working memory test - delayed response task -
higher activity in the prefrontal cortex during the
delay
7/28/2019 Physiologi Learn
28/46
Physiology of Memory
Types of amnesia
1. Retrograde amnesia
Loss of memories already formed due to
brain damage
But can still form new LTMs
Example: Patient has stroke and no longer
recognizes family members. Common symptom of Alzheimers disease
7/28/2019 Physiologi Learn
29/46
Physiology of Memory
Types of amnesia
2. Anterograde amnesia
Loss of ability to form new long-term
memories
Previously stored memories may still be
intact
Korsakoffs syndrome You meet patient,tell him your name, he can repeat it You
leave room, come back 2 minutes later, he
doesnt know who you are.
7/28/2019 Physiologi Learn
30/46
Hippocampus
Thought to play a role in encodinginformation from STM to LTM
Case of H.M.
Both hippocampi removed to control severeepilepsy
No problems with short-term memory
Lost ability to form new long-term memories
(anterograde amnesia) LTM intact for events until shortly beforesurgery
Symptoms similar to Korsakoffs syndrome,
but different area of brain affected
7/28/2019 Physiologi Learn
31/46
Memory and learning
Hippocampus
H. M. - removal of hippocampus:
Retrograde amnesia (loss of memory for events
occurring shortly before brain damage)
intact short-term/working memory
acute anterograde amnesia (declarative memory)
(loss of memory for events happening after thebrain damage)
intact procedural memory
better implicit than explicit memory
7/28/2019 Physiologi Learn
32/46
Memory and learning
Theories of the hippocampal function:
declarative, explicit memory
supported by the H.M. case
hippocampal damage may impair implicit memory
it does not damage all the memory in nonhumans
in tasks similar those requiring declarative memory
from humans
dependence on the experimental protocol in
delayed matching-to-sample and delayed
nonmatching-to-sample task experiments
7/28/2019 Physiologi Learn
33/46
Memory and learning spatial memory
rat maze experiments hippocampus is involved also in nonspatial aspects of the
tasks
configural learning
the meaning of the stimulus depends on what other stimuliare paired with it, e.g. A + food; B + food; AB + no food
hippocampus is involved in nonconfigural learning if its
sufficiently difficult
binding memories
input from many parts of cortex (secondary and tertiary
areas)
7/28/2019 Physiologi Learn
34/46
Memory and learning
Brain damage and memory Korsakoff's syndrome brain damage due to
prolonged deficiency in thiamine (B1).
Thiamine deficiency loss of neurons in dorsomedial thalamus
damage to prefrontal cortex
apathy, confusion, retrograde and anterograde
amnesia;
better implicit memory (good at priming tasks);
impaired reasoning about own memories;
confabulation;
7/28/2019 Physiologi Learn
35/46
Memory and learning
Alzheimer's disease
forgetfulness, proceeding into serious memory loss
confusion, depression, restlessness
hallucinations
sleeplessness, loss of appetite
impaired procedural memory, explicit memory,
attention.
Genetic involvement;
excessive accumulation of beta-amyloid plaques
atrophy of cerebral cortex (esp. entorhinal),
hippocampus
formation of neurofibrillary tangles
7/28/2019 Physiologi Learn
36/46
Memory and learning
Physiology of learning and memory
Hebbian learning
a cell A that successfully stimulated cell B in thepast becomes more successful in the stimulation of
B in the future
Hebbian learning and classical conditioning
Single cell mechanisms of invertebrate
plasticity
Aplysia
7/28/2019 Physiologi Learn
37/46
Memory and learning
habituation depends on a change in
synapse between the sensory and motor
neuron
7/28/2019 Physiologi Learn
38/46
Memory and learning
Sensitisation
strong skin stimulation
excitation of facilitating interneuron
serotonine release on presynaptic terminals of
sensory neurons
metabotropic effects
prolonged action potential longer opening of voltage-gated calcium channels
greater transmitter release per action potential
7/28/2019 Physiologi Learn
39/46
Memory and learning
associative learning
similar to the sensitisation
pairing the CS (conditioned stimulus) and UCS(unconditioned stimulus) increases presence of
calcium in the presynaptic terminal (due to CS)
Intensified metabotropic effects
More transmitter released than in sensitisation
7/28/2019 Physiologi Learn
40/46
Memory and learning Physiology of vertebrate plasticity
long term potentiation (LTP)a response enhancement at certain synapses due to rapid
intensive stimulus delivered simultaneously to a neuron by
several axons
underlying mechanisms vary between the brain areas
prominent in hippocampus
attractive as a cellular basis of learning and memory:
Specificity only the active synapses become
strengthened
Cooperativity simultaneous (almost) stimulationproduces LTP
Associativity LTP is hebbian (no need for actionpotential depolarisation sufficient)
7/28/2019 Physiologi Learn
41/46
Memory and learning Biochemistry of LTP main actors:
Glutamate receptors
AMPA opens sodium channels
NMDA allows sodium and calcium ions to enter
the neuron
responds to glutamate ONLY when the membrane is
partly depolarised
removal of magnesium ions blocking NMDA
receptors
glutamate excitation of NMDA receptors opens
NMDA-dependent calcium channels
7/28/2019 Physiologi Learn
42/46
Memory and learning
large influx of calcium activates protein kinases:
protein kinase C (PKC)
CaMKII (calcium calmodulin-dependent protein
kinase)
alteration the structure (phosphorylation) of
AMPA receptors
conversion of some NMDA receptors into AMPA
receptors creation of more AMPA receptors
increased dendritic branch growth
increased dendritic responsiveness to subsequent
incomin of lutamate
7/28/2019 Physiologi Learn
43/46
Memory and learning
Long term depression (LTD)
a prolonged decrease in response to synaptic
input repeatedly paired to another input at alow frequency
LTP (LTD) may be involved in memory
formation - recently questioned
7/28/2019 Physiologi Learn
44/46
Memory and learning
Potential problems with LTP/LTD as
correlates of memory formation:
Importance of protein phosphorylation
Protein phosphorylation is not permanent
protein molecules are not permanent (app. 2
weeks lifetime)
7/28/2019 Physiologi Learn
45/46
Memory and learningAlternative mechanisms:
continual phosphorylation of proteins
main suspect: persistently active protein kinases (PKC)
large elevation of calcium activates calpain (enzyme)
breaking the peptide bond between regulatory and
catalytic parts of PKC
freeing the catalytic region (remains active) leading to
continual proteins phosphorylation problem with PKC solution limited time (minutes to
hoursbut Bruces work)
7/28/2019 Physiologi Learn
46/46
Memory and learning
protein synthesis
evidence from experiments with protein synthesis
inhibitors
animals injected with these inhibitors learn normally
but fail to recall during later testing
structural changes
change in the number of synapses
morphological reorganisation
Top Related