Download LEARNING AND INFORMATION PROCESSING

LEARNING AND INFORMATION
PROCESSING
PSY 111
LECTURER
MRS.T.N TUTURU
THIS COURSE IS COMPOSED OF
TWO PARTS
• The first part we will look at learning
• Then the second part looks at information
processing
• These two however are connected they
are not totally separate.
WHAT IS LEARNING?
• Santrock 2003 defines
learning as:
• “Learning is a process by
which experience produces a
relatively enduring change in
an organism’s behaviour or
capabilities
WHAT IS INFORMATION
PROCESSING?
•
Information processing refers to the mental
operations by which our sensory experiences
are converted into knowledge. It focuses upon
the ways in which we receive, integrate, retain
and use information.
• According to the information processing view
point three stages are involved in in acquiring
every relatively permanent memory:
i) Encoding
ii) Storage
iii) retrieval
NOW BACK TO LEARNING LETS LOOK
AT THE FOUR FACTORS THAT FORM
THE DEFINITION OF LEARNING
1) Learning is inferred from a
change in behaviour/performance
2) Learning results in an inferred
change in memory
3) Learning is the result of
experience
4) Learning is relatively permanent
MORE DEFINITIONS OF LEARNING
Wood & Wood (2000) define learning as “A relatively
permanent change in behaviour, knowledge, capability
or attitude that is acquired through experience and
cannot be attributed to illness, injury or maturation.
Gross (2005) definition of learning is “ Learning
therefore, normally implies a fairly permanent change
in a person’s behavioural performance.
Ormrod (1995) defines learning as a relatively
permanent change in mental associations due to
experience.
Theories of learning
• These can be classified into three broad groups:
1. Behaviourist/Connectionist: chiefly concerned
with Stimulus (S) and response (R) connections
2. Cognitivist: based on the belief that inner functions
of human are also worthy of study. The brain,
perception, memory, personality motivation are but a
few internal mental structures and processes which
affect human behaviour. Child (2004)
3. Social Learning Theory: Social learning theory
focuses on the learning that occurs within a social
context. It considers that people learn from one
another, including such concepts as observational
learning, imitation, and modeling
Behaviourist Theories
• The Behavioral Learning Theory focuses on the
learning of tangible, observable behaviors or
responses. Through a continual process of stimulating
a desired response and reinforcing that desired
response, the learner eventually changes their
behavior to match the desired response. Learning
occurs in the most basic way, and it is something that
we can see. As long as the desired behavior is
occurring, then learning has occurred. That is not to
say that there is not a mental process involved in
learning the behavior, but the behavioral theorists do
not address this mental process. They limit their
explanation to the very rudimentary behavioral
change. They don’t really even acknowledge that the
change in behavior might require in-depth mental
processes to bring about
Cognitive Theories
• The Cognitive Learning Theory focuses not on the behavioral
outcomes but on the thought processes involved in human
learning. These theorists make a distinction between learning
and memory. Learning is viewed as the acquisition of new
information. Memory, on the other hand, is related to the
ability to recall information that has been previously learned.
Cognition is about a process by which we receive
information, we process that information, and then we do
something with that information, either discarding it or
keeping it. Information is everything. The weather, the time,
the lighting, and what’s on the chalkboard, are all information
that could be processed concurrently. How we take in these
pieces of information and filter or encode them so that only
the information on the chalkboard is hopefully remembered, is
part of our cognitive learning process.
The Social Learning Theory
• Social Learning Theory [SLT] describes how the
environment affects a person’s behavior. It’s not
that SLT is a combination of behavioral and
cognitive, but that SLT rejects that either one of
these occurs alone or without the affect of
outside stimulus. The general principles of SLT
are that people learn by observing; that learning
can occur without a change in behavior; and
that consequences of behavior and cognition,
both play a role in learning.
THE BEHAVIOURISTS
CLASSICAL CONDITIONING: I.P PAVLOV
• Classical Conditioning One important type of learning,
Classical Conditioning, was actually discovered
accidentally by Ivan Pavlov(1849-1936). Pavlov was a
Russian physiologist who discovered this phenomenon
while doing research on digestion. His research was aimed
at better understanding the digestive patterns in dogs.
During his experiments, he would put meat powder in the
mouths of dogs who had tubes inserted into various
organs to measure bodily responses. What he discovered
was that the dogs began to salivate before the meat
powder was presented to them. Then, the dogs began to
salivate as soon as the person feeding them would enter
the room. He soon began to gain interest in this
phenomenon and abandoned his digestion research in
favour of his now famous Classical Conditioning study
CLASSICAL CONDITIONING
• Pavlov began pairing a bell sound with the meat
powder and found that even when the meat powder
was not presented, the dog would eventually begin to
salivate after hearing the bell.
• Since the meat powder naturally results in salivation,
these two variables are called the unconditioned
stimulus (UCS) and the unconditioned responses
(UCR), respectively.
• Bell and salivation are not naturally occurring; the dog
was conditioned to respond to the bell. Therefore, the
bell is considered the conditioned stimulus (CS),
and the salivation to the bell, the conditioned
response (CR).
CLASSICAL CONDITIONING
Stage 1
(Before learning)
Stage 2
(During learning)
Stage 3
(After learning)
Food
Unconditioned Stimulus
Bell
Conditioned
Stimulus
Bell
Conditioned Stimulus
Food
Unconditioned
Stimulus
Salivation
Unconditioned Response
Salivation
Unconditioned
Response
Salivation
Conditioned Response
Terminology in Classical
Conditioning
a) Unconditioned Stimulus (US) - a stimulus that
evokes an unconditioned response without any prior
conditioning (no learning needed for the response to
occur).
b) Unconditioned Response (UR) - an unlearned
reaction/response to an unconditioned stimulus that
occurs without prior conditioning.
c) Conditioned Stimulus (CS) - a previously neutral
stimulus that has, through conditioning, acquired the
capacity to evoke a conditioned response.
d) Conditioned Response (CR) - a learned reaction
to a conditioned stimulus that occurs because of
prior conditioning.
Basic Principles: In Classical
Conditioning
• Acquisition - formation of a new CR tendency. This means
that when an organism learns something new, it has been
"acquired".
• Pavlov believed in contiguity - temporal association between
two events that occur closely together in time. The more closely
in time two events occurred, the more likely they were to
become associated; as time passes, association becomes less
likely.
• For example, when people are toilet training a child -- you
notice that the child messed himself on his way to the
bathroom. If the child had the accident hours ago, it will not do
any good to scold the chid because too much time has passed
for the child to associate your scolding with the accident. But, if
you catch the child right after the accident occurred, it is more
likely to become associated with the accident.
Four different ways conditioning can
occur -- order that the stimulus-response
can occur:
• 1. delayed conditioning (forward) - the CS is presented before the US
and it (CS) stays on until the US is presented. This is generally the best,
especially when the delay is short.
example - a bell begins to ring and continues to ring until food is
presented.
• 2. trace conditioning - discrete event is presented, then the US occurs.
Shorter the interval the better, but as you can tell, this approach is not
very effective.
example - a bell begins ringing and ends just before the food is
presented.
• 3. simultaneous conditioning - CS and US presented together. Not
very good.
example - the bell begins to ring at the same time the food is presented.
Both begin, continue, and end at the same time.
• 4. backward conditioning - US occurs before CS.
example - the food is presented, then the bell rings. This is not really
effective.
Basic Principles: In Classical
Conditioning
• Extinction - this is a gradual weakening and eventual disappearance of
the CR tendency. Extinction occurs from multiple presentations of CS
without the US.
• Essentially, the organism continues to be presented with the conditioned
stimulus but without the unconditioned stimulus the CS loses its power to
evoke the CR. For example, Pavlov's dogs stopped salivating when the
dispenser sound kept occurring without the meat powder following.
• Spontaneous Recovery - sometimes there will be a reappearance of a
response that had been extinguished. The recovery can occur after a period
of non-exposure to the CS. It is called spontaneous because the response
seems to reappear out of nowhere.
• Stimulus Generalization - a response to a specific stimulus becomes
associated to other stimuli (similar stimuli) and now occurs to those other
similar stimuli.
• For Example - a child who gets bitten a dog, later becomes afraid of all dogs.
The original fear evoked by one dog has now generalized to ALL dogs.
Little Albert and generalization
• John Watson conditioned a baby (Albert) to be afraid
of a white rabbit by showing Albert the rabbit and then
slamming two metal pipes together behind Albert's
head. The pipes produced a very loud, sudden noise
that frightened Albert and made him cry. Watson did
this several times (multiple trials) until Albert was
afraid of the rabbit. Previously he would pet the rabbit
and play with it. After conditioning, the sight of the
rabbit made Albert scream -- then what Watson found
was that Albert began to show similar terrified
behaviours to Watson's face (just looking at Watson's
face made Albert cry. What a shock!). What Watson
realized was that Albert was responding to the white
beard Watson had at the time. So, the fear evoked by
the white, furry, rabbit, had generalized to other white,
furry things, like Watson's beard.
Basic Principles: In Classical
Conditioning
• Stimulus Discrimination - learning to respond to one
stimulus and not another. Thus, an organisms
becomes conditioned to respond to a specific stimulus
and not to other stimuli.
• For Example - a puppy may initially respond to lots of
different people, but over time it learns to respond to
only one or a few people's commands.
• Higher Order Conditioning - a CS can be used to
produce a response from another neutral stimulus
(can evoke CS). There are a couple of different orders
or levels. Let's take a "Pavlovian Dog-like" example to
look at the different orders:
Higher Order Conditioning
•
In this example, light is paired with food. The food is a US since it produces a response without any prior
learning. Then, when food is paired with a neutral stimulus (light) it becomes a Conditioned Stimulus (CS) –
•
First Order
1) Light US (food)
\-->UR salivation
•
Second Order
3) tone -- light
\--> CR (salivation)
•
2) Light—(Food)
\-->CR (Salivation)
4) tone -- light
\--> CR (salivation )
Higher Order Conditioning
• Higher Order Conditioning:
Conditioning that occurs when a
neutral stimulus is paired with an
existing conditioned stimulus,
becomes associated with it, and gains
the power to elicit the same
conditioned response. Wood & Wood
(2000).
Classical Conditioning in Everyday Life
•
One of the great things about conditioning is that we can see it all
around us. Here are some examples of classical conditioning that you
may see:
1. Conditioned Fear & Anxiety - many phobias that people experience
are the results of conditioning.
•
For Example - "fear of bridges" - fear of bridges can develop from many
different sources. For example, while a child rides in a car over a
dilapidated bridge, his father makes jokes about the bridge collapsing
and all of them falling into the river below. The father finds this funny
and so decides to do it whenever they cross the bridge. Years later, the
child has grown up and now is afraid to drive over any bridge. In this
case, the fear of one bridge generalized to all bridges which now evoke
fear.
•
Classical conditioning can be used to help people reduce fears.
Counter conditioning involves pairing the CS that elicits the fear with a
US that elicits positive emotions (UR). For example a person afraid of
snakes but loves chocolate ice cream is shown a snake then given the
ice cream , Classical conditioning helps associate the snake with good
feelings.
Classical Conditioning in Everyday Life
2.
Classical conditioning (CC) has a grate deal of survival
value for the individual (Vernoy 1995) Because of CC we jerk
our hands away before they are burnt by fire
3. Advertising - modern advertising strategies evolved from
John Watson's use of conditioning. The approach is to link an
attractive US with a CS (the product being sold) so the
consumer will feel positively toward the product just like they
do with the US.
US --> CS --> CR/UR
attractive person --> car --> pleasant emotional response
4. CC is not restricted to unpleasant emotions, such as fear.
Among other things in our lives that produce pleasure
because they have been conditioned might be the sight of a
rainbow, hearing a favourite song. If you have positive
romantic experience , the location in which the experience
took place can become a CS thru the pairing of the place with
the event (UCS).
Classical Conditioning in Everyday Life
5. CC conditioning can be involved in certain
aspects of drug use. When drugs are
administered in particular circumstances, at a
particular time of day, in a particular location the
body reacts in anticipation of receiving the drug
FACTORS INFLUENCING CC: Wood & Wood (2000)
1.
2.
3.
4.
How reliably the CS predicts the UCS: The neutral stimulus
must reliably predict the occurrence of the UCS. A smoke
alarm that never goes off except in response to a fire will
elicits more fear when it sounds than one that occasionally
gives false alarms
The number of pairings of the CS and the UCS: The
greater the number of pairings, the stronger the conditioned
response. But one pairing is all that is needed to classically
condition a taste aversion or a strong emotional response.
The intensity of the UCS: If a CS is paired with a very strong
UCS, the CR will be stronger and will be acquired more
rapidly than if paired with a weaker UCS.
The temporal relationship between the CS and the UCS:
Conditioning takes place faster if the CS occurs shortly before
the UCS. It takes place more slowly or not at all when the two
stimuli occur at the same time. Conditioning rarely takes
place when the CS follows the UCS.
OPERANT CONDITIONING
• In the late nineteenth century, psychologist Edward Thorndike
proposed the law of effect. The law of effect states that any
behaviour that has good consequences will tend to be
repeated, and any behaviour that has bad consequences will
tend to be avoided. In the 1930s, another psychologist, B. F.
Skinner, extended this idea and began to study operant
conditioning. Operant conditioning is a type of learning in which
responses come to be controlled by their consequences.
Operant responses are often new responses
• Operant conditioning can be defined as a type of learning in which
voluntary (controllable; non-reflexive) behaviour is strengthened if it is
reinforced and weakened if it is punished (or not reinforced).
• The term "Operant" refers to how an organism operates on the
environment, and hence, operant conditioning comes from how
we respond to what is presented to us in our environment. It
can be thought of as learning due to the natural consequences
of our actions.
Skinner's views of Operant Conditioning
• a) Operant Conditioning is different from Classical Conditioning in that the
behaviours studied in Classical Conditioning are reflexive (for example,
salivating). However, the behaviours studied and governed by the principles
of Operant Conditioning are non-reflexive (for example, gambling). So,
compared to Classical Conditioning, Operant Conditioning attempts to
predict non-reflexive, more complex behaviours, and the conditions in which
they will occur. In addition, Operant Conditioning deals with behaviours that
are performed so that the organism can obtain reinforcement.
• b) there are many factors involved in determining if an organism will engage
in a behaviour - just because there is food doesn't mean an organism will eat
(time of day, last meal, etc.). SO, unlike classical conditioning...(go to "c",
below)
• c) in Operant Cond., the organism has a lot of control. Just because a
stimulus is presented, does not necessarily mean that an organism is going
to react in any specific way. Instead, reinforcement is dependent on the
organism's behaviour. In other words, in order for an organism to receive
some type of reinforcement, the organism must behave in a specific manner.
For example, you can't win at a slot machine unless several things happen,
most importantly, you pull the lever. Pulling the lever is a voluntary, nonreflexive behaviour that must be exhibited before reinforcement (hopefully a
jackpot) can be delivered.
Skinner's views of Operant Conditioning
•
d) in classical conditioning, the controlling stimulus comes before the behaviour. But
in Operant Conditioning, the controlling stimulus comes after the behaviour. If we
look at Pavlov's meat powder example, you remember that the sound occurred
(controlling stimulus), the dog salivated, and then the meat powder was delivered.
With Operant conditioning, the sound would occur, then the dog would have to
perform some behaviour in order to get the meat powder as a reinforcement. (like
making a dog sit to receive a bone).
•
e) Skinner Box - This is a chamber in which Skinner placed animals such as rats and
pigeons to study. The chamber contains either a lever or key that can be pressed in
order to receive reinforcements such as food and water.
•
* the Skinner Box created Free Operant Procedure - responses can be made and
recorded continuously without the need to stop the experiment for the experimenter
to record the responses made by the animal.
•
f) Shaping - operant conditioning method for creating an entirely new behaviour by
using rewards to guide an organism toward a desired behaviour (called Successive
Approximations). In doing so, the organism is rewarded with each small
advancement in the right direction. Once one appropriate behaviour is made and
rewarded, the organism is not reinforced again until they make a further
advancement, then another and another until the organism is only rewarded once the
entire behaviour is performed.
Principles of Reinforcement
• Reinforcement
• Reinforcement is delivery of a consequence that increases the likelihood
that a response will occur. Positive reinforcement is the presentation of a
stimulus after a response so that the response will occur more often.
Negative reinforcement is the removal of a stimulus after a response so
that the response will occur more often. In this terminology, positive and
negative don’t mean good and bad. Instead, positive means adding a
stimulus, and negative means removing a stimulus.
• Skinner identified two types of reinforcing events - those in which a
reward is given; and those in which something bad is removed. In either
case, the point of reinforcement is to increase the frequency or
probability of a response occurring again.
1) positive reinforcement - give an organism a pleasant stimulus when the
operant response is made. For example, a rat presses the lever (operant
response) and it receives a treat (positive reinforcement)
2) negative reinforcement - take away an unpleasant stimulus when the
operant response is made. For example, stop shocking a rat when it
presses the lever.
Two Types of Reinforcers
1) primary reinforcer - stimulus that naturally strengthens any
response that precedes it (e.g., food, water, sex) without the
need for any learning on the part of the organism. These
reinforcers are naturally reinforcing.
• Primary reinforcers, such as food, water, and caresses, are
naturally satisfying.
• 2) secondary/conditioned reinforcer - a previously neutral
stimulus that acquires the ability to strengthen responses
because the stimulus has been paired with a primary reinforcer.
For example, an organism may become conditioned to the
sound of food dispenser, which occurs after the operant
response is made. Thus, the sound of the food dispenser
becomes reinforcing. Notice the similarity to Classical
Conditioning, with the exception that the behaviour is voluntary
and occurs before the presentation of a reinforcer.
• Secondary reinforcers, such as money, fast cars, and good
grades, are satisfying because they’ve become associated with
primary reinforcers.
Schedules of Reinforcement
•
•
•
•
•
•
There are four main types of intermittent schedules, which fall into two categories:
ratio or interval. In a ratio schedule, reinforcement happens after a certain number of
responses. In an interval schedule, reinforcement happens after a particular time
interval.
In a fixed-ratio schedule, reinforcement happens after a set number of responses,
such as when a car salesman earns a bonus after every three cars he sells.
In a variable-ratio schedule, reinforcement happens after a particular average
number of responses. For example, a person trying to win a game by getting heads
on a coin toss gets heads every two times, on average, that she tosses a penny.
Sometimes she may toss a penny just once and get heads, but other times she may
have to toss the penny two, three, four, or more times before getting heads.
In a fixed-interval schedule, reinforcement happens after a set amount of time,
such as when an attorney at a law firm gets a bonus once a year
Another example - when you wait for a bus example. The bus may run on a specific
schedule, like it stops at the nearest location to you every 20 minutes. After one bus
has stopped and left your bus stop, the timer resets so that the next one will arrive in
20 minutes. You must wait that amount of time for the bus to arrive and stop for you
to get on it.
In a variable-interval schedule, reinforcement happens after a particular average
amount of time. For example, a boss who wants to keep her employees working
productively might walk by their workstations and check on them periodically, usually
about once a day, but sometimes twice a day, or some-times every other day. If an
employee is slacking off, she reprimands him. Since the employees know there is a
variable interval between their boss’s appearances, they must stay on task to avoid a
reprimand.
Reinforcement Schedules Compared: Wood & Wood
Schedules of
reinforcement
Response Rate
Pattern of
responses
Resistance to
extinction
Fixed-Ratio
Schedule
Very High
Steady Response
with low ratio.
Brief pause after
each reinforcement
with very high ratio.
The high the ratio
the more resistance
to extinction
Variable-Ratio
Schedule
Highest Response
Rate
Constant response
pattern no pauses.
Most resistance to
extinction
Fixed-Interval
Schedule
Lowest Response
Rate
Long pause after
reinforcement,
followed by gradual
acceleration
The longer the
interval the more
resistance to
extinction
Variable-Interval
Schedule
Moderate
Stable uniform
response.
More resistance to
extinction than fixed
interval schedule with
same average
interval
Punishment
• Punishment is the delivery of a consequence that
decreases the likelihood that a response will occur.
• Whereas reinforcement increases the probability of a
response occurring again, the premise of punishment
is to decrease the frequency or probability of a
response occurring again.
• b) there are two types of punishment:
• 1) Positive - presentation of an aversive stimulus to
decrease the probability of an operant response
occurring again. For example, a child reaches for a
cookie before dinner, and you slap his hand.
• 2) Negative - the removal of a pleasant stimulus to
decrease the probability of an operant response
occurring again. For example, each time a child says a
curse word, you remove one dollar from their piggy
bank.
Applications of Operant Conditioning
•
•
•
a) In the Classroom
Skinner thought that our education system was ineffective. He suggested that one
teacher in a classroom could not teach many students adequately when each child
learns at a different rate. He proposed using teaching machines (what we now call
computers) that would allow each student to move at their own pace. The teaching
machine would provide self-paced learning that gave immediate feedback,
immediate reinforcement, identification of problem areas, etc., that a teacher could
not possibly provide.
b) In the Workplace
many factory workers are paid according to the number of some product they
produce. A worker may get paid $50 000 for every 100 candles he makes.
Another example - study by Pedalino & Gamboa (1974) - To help reduce the
frequency of employee tardiness, the researchers implemented a game-like system
for all employees that arrived on time. When an employee arrived on time, they were
allowed to draw a card. Over the course of a 5-day workweek, the employee would
have a full hand for poker. At the end of the week, the best hand won $20. This
simple method reduced employee tardiness significantly and demonstrated the
effectiveness of operant conditioning on humans.
Applications of Operant Conditioning
• c) Behaviour modification: is the application of operant
conditioning techniques to modify behaviour. It is used to help
people with a wide variety everyday behaviour problems,
including, obesity, smoking, alcoholism, delinquency and
aggression.
• d) The Premack Principle: States that of any two responses
the one that is more likely to occur can be used to reinforce the
response that is less likely to occur. People prefer doing certain
things more than others. E.g. a child may prefer to play outside
rather than do his homework. A parent could then use the
playing response to reinforce the and increase the occurrence
of doing homework by promising more play time only after
homework was finished.