-Classical Conditioning
-Ivan Pavlov
-John Watson
-Edwin Guthrie
-Albert Bandura
-Closing Comments on Classical Conditioning
-Operant Conditioning
-B.F. Skinner
-Edward Thorndike
-Clark Hull
-Ivar Lovass
THE HISTORY OF BEHAVIORISM
There have been two major schools of thought and study within
the Behaviorist orientation. The earlier "Classical Conditioning"
school studied stimuli (events) and responses (reactions) to them.
The later "Operant Conditioning" school noted that in addition to a stimulus
spurring a response, it was also important to attend to the consequence
that followed the response. The operant school, as with the earlier
classical view focuses solely on observable actions displayed by individuals.
Emotions and thoughts are not considered in the analysis of behavior (as
in the PsychoEducational approach) because they do not provide objective,
observable data for evaluation.
CLASSICAL CONDITIONING -
This earlier school of behaviorism studied the connection
between a stimulus and the response it incites. Prominent researchers
identified with this orientation noted that an event that formerly did
not elicit a behavior (known as a neutral stimulus) can be made to
do so by pairing (presenting) it with an unconditioned (already present)
stimulus. This newly effective stimulus (and the responses to it)
are said to be "conditioned" (trained).
Classical behaviorists also believed that the brain contains
two systems, "excitation" and "inhibition". The excitation system
increases neural activity in response to a stimulus or happening, and prompts
a human or animal to display a certain behavior (response). The inhibition
system blocks other behaviors from being shown when that stimulus appears.
For example, when the phone rings, the excitation system typically causes
the response sequence of going to the phone, picking it up, and offering
a greeting. The inhibition system prevents the display of other responses
(e.g., combing one's hair, ripping up boxes, opening windows).
Individuals who display socially inappropriate behaviors were believed to be having problems discriminating between stimuli. Both of their systems become excited. For example, consider the case of a child who is physically abused by a male adult at home and cowers in fear at the approach of a male teacher who has not been abusive to the child. The child generalizes instead of discriminates between the two stimuli (approach of the different men). The inhibition system that should prevent the display of the fear response around non-abusive men instead becomes excited, allowing the "inappropriate" (in that situation) response to appear.
The different reactions to events that we witness in different people is believed to be due to the differing strengths of the two processes in each of us. Advertisers attempt to excite your inhibition system by causing a buying response to a stimuli (product) that previously did not bring about such a response. Conversely, the process of "desensitization", in which people attempt to overcome their phobias (e.g., fear of flying, fear of driving over bridges) involves numbing an excited inhibition system. Clients are placed in non-threatening situations that progressively become more similar to the fear inducing situation. By handling low anxiety situations and discovering that there is no need for fear, the inhibition system is strengthened (for that particular event and response).
Ivan Pavlov's Contributions
Pavlov was aware that food (unconditioned stimulus -UCS) triggered
salivation (unconditioned response - UCR) in his laboratory dogs.
However, he noted that the dogs salivated before the standard feeding time.
He was perplexed as to why dogs would salivate when there was no food present
to be digested. He decided to investigate this "psychic secretion"
phenomenon by manipulating circumstances. He "paired" the ringing
of a bell (a neutral stimulus that did not trigger salivation) with the
presentation of the UCS (food). After about 10-20 pairings or "trials"
the formerly neutral stimulus of the bell, activated salivation...even
when no food was presented. The neutral stimulus became a CS that
activated salivation (now referred to as being a CR because it was trained
to occur at the sound of the bell).
Other research in Pavlov's laboratory made other principles of learning apparent. He noted that after several trials of ringing the bell with no presentation of the food, the CS (ringing bell) no longer produced the CR (salivation). The salivation behavior at the stimulus of the bell also extinguished if the time period between the bell and the presentation of the food was too great. The CS lost it's ability to stimulate a response because it was no longer associated with the UCS.
John Watson's Contributions
Watson is the acknowledged "father" of behaviorism. In
1913, his soon-to-be-famous article, "Psychology as the behaviorist views
it" was published. This publication established the behaviorist school
of behavioral investigation and intervention. Watson believed that
psychologists should study actions, not feelings and thoughts. He
desired a more objective science although he did believe in three innate
emotions: fear (due to psychological shock or being in the presence of
perceived danger), anger (from frustration of one's efforts to accomplish
something), and love (which can be traced back to a baby's need for touch
and physical stimulation) . According to Watson, new responses shown
by humans were either recently learned, simply old responses combined or
sequenced to produce a new complex response, or the display of old responses
to a new stimuli ("generalization" to a new setting).
Watson's most famous research study involved "Albert", a young
child of a laboratory worker. Albert was brought to the laboratory
where he entertained himself by playing with the lab rats. During
the experiment, Albert was presented with a rat (stimuli) that then brought
about the play response ("love"...contact with a warm, fuzzy, moving animal
that provides physical stimulation). Then the investigator walked
up behind Albert while he was enjoying his play with the rats, and stuck
a metal bar with a hammer. This act created a loud sound that frightened
Albert. After seven "pairings" of the original stimuli (presenting
Albert with a white rat) with the new stimuli (the loud sound), Albert
showed a fear reaction (crying) at the presentation of the original stimuli
(a white rat; UCR). This fear response "generalized" to new stimuli:
Albert also showed fear (CR) when things (CS) similar to the fuzzy lab
rat were presented (e.g., men with beards, dogs, fur coats, Santa Claus
masks). This fear response extinguished after about a month of no
loud sounds being made when lab rats were present. The lab rats were
no longer associated with the frightening noise.
His experiences led Watson in 1925 to trumpet the now famous statement: "Give me a dozen healthy infants, well formed, and my own special world to bring them up in, and I'll guarantee to take any one at random and train him to become any type of specialist I might select - doctor, lawyer, artist, merchant-chief, and yes, even beggarman and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestry." He never made good on his boast as he gave up scientific investigation and went into the advertising business (a business that to this day makes use of classical conditioning by trying to encourage an old response, buying something, to a new stimuli/product).
Edwin Guthrie's Contributions
Guthrie developed the principle of "all or none" learning (one
either displays a response or doesn't in the presence of a stimulus).
He believed that individuals forget or lose a previous response to a stimulus
because a new behavior is found to be more beneficial, and the inhibition
system allows only one response to occur to a stimulus. He believed
that disordered behavior was due to responses competing to occur to a particular
stimulus, thus causing stress and confusion.
Guthrie also described "one trial learning", pointing out that some new skills (responses) can be adopted (learned) after doing it only once. The benefits of the behavior are quickly recognized, and the behavior is shown again in the presence of the stimuli. Certainly, this type of learning does not apply to penmanship or video games in which multiple practice must be conducted to develop skill. However, if you step off of a curb and get hit by a bus, chances are that you'll learn to stop at the curb and look for vehicles next time. There is no need for repeated practice sessions.
Albert Bandura's Contributions
Bandura pointed out that for some learning (display) of new behaviors,
not even one trial is needed. Sometimes people observe another engaging
in an action they don't yet display, and then perform that behavior well
on the first attempt. In a famous experiment, children watched an
adult enter a preschool classroom, walk over to a table, pick up a hammer,
and hit a large inflatable doll that had a weighted bottom (so that the
doll would return to an upright position after being struck). The
adult then left and the child who had been watching was allowed into the
room. Where did the child go? Directly to the doll to hit it
with the hammer. A new behavior was being displayed even though there
had been no coaching or practice. Later studies found that the characteristics
of the model (the person demonstrating the behavior) had an effect on the
chances of the behavior being emulated. High status (admired) models
and those who were reinforced for their behavior were most likely to have
their response modeled. Aggressive behavior was more likely to be
modeled than non-aggressive behavior. Additionally, even if the behavior
was not initially demonstrated by the child in the presence of the stimulus,
an offer of a reward would bring about that observed response.
Closing Comments On Classical
Conditioning
Classical conditioning can not explain all of human behavior:
some behaviors are developmental in nature (e.g., babbling in infants),
and higher level cognitive thought can often overrule the machine-like
reflex responses that have been previously built. However, these
early investigations helped to identify principles of human (and other
animal) learning. The operant school of behaviorism would extend
our understanding of behavior.
OPERANT CONDITIONING - This later school of behaviorism (also known as reinforcement theory) emerged from the research of B.F. Skinner. This school of thought and practice focuses on the effect of environmental consequences. The term "operant" derives from Skinner's experiments in which rats and pigeons "operated" on the environment instead of being passive (as with Pavlov's dogs, Watson's Albert, and other subjects in classical conditioning experiments).
B.F. Skinner's Contributions
Skinner, the greatest behavioral psychologist of all time, is
known as the "father" of operant conditioning. He rejected the idea of
inner causes for behavior, and placed emphasis on observable behavior as
opposed to the theorizing, based on unverifiable evidence, often done by
others. He discovered that whether a response to a stimulus continues
to occur depends on the consequence that follows that behavior. The
promptness of administration of that consequence is also important (more
timely consequences have a greater effect). He also experimented
with different "schedules of reinforcement" (see below), and devised a
procedure known as "shaping" (see below).
Edward Thorndike's Contributions
Thorndike is considered to be the originator of reinforcement theory
and the "father" of educational psychology. He described several
principles or laws regarding the effect of consequences upon behavior.
His "law of effect" stated that the strength of the connection between
a stimuli and a response is an effect or result of the consequence that
follows the behavior. His "law of readiness" stated that an individual's
physiology effects the influence of consequences. Individuals will
be less affected by consequences when they are sleepy, inebriated, or otherwise
pre-occupied by other things (birth defects and genetic limitations to
learning also apply here). The "law of exercise" stated that a connection
between a stimulus and a response becomes stronger with practice (and weaker
in the absence of repeated trials).
Clark Hull's Contributions
Hull devised perhaps the most complex, formal and systematic theory
of behavior ever presented. This formulation may have been the result
of his background as a physicist and engineer. It is much too complicated
to explain here, however, certain principles were identified. He
noted that the strength of a stimulus is important in whether a response
is displayed. For example, someone quickly whispering "boo" won't
cause another person to flinch, but yelling it is more likely to do so.
The importance of the strength of the reinforcer on the display
of the response was also described. For example, an adolescent who
runs an errand for an adult and receives a penny in payment, may not agree
to run another errand. However, payment of a dollar is more likely
to result in a future errand running response to the request. Hull
also described "secondary reinforcement" in which a previously neutral
stimulus takes on reinforcing qualities. For example, giving a dollar
to a six month old child is less likely to produce a reaction to a request
than giving it to a six year old. An unknown actor's autograph
may not bring any money until success makes that previously neutral stimuli
(no response happens to it's presentation) become a desirable commodity.
Ivar Lovass' Contributions
Lovass is known as the "father" of applied behavior analysis (ABA),
the behaviorist procedures that involve the systematic environmental modifications
used to understand and change the behaviors of humans. He worked
with children with autism (a condition characterized by problems in communication
and behavior). These ABA procedures (also known as "behavior modification",
"behavioral treatment", or "behavioral intervention") are the only ones
proven to work with these impaired students. His program of intensive
one-to-one teaching with repeated trials (practice sessions) was based
on the work of Skinner and others. Side note: Dr. Lovass became
a controversial figure early in his career when he advocated for the use
of physical punishment ("aversive therapy") to teach children with autism.
As his career developed, he dropped this orientation and developed positive
and novel ways to teach these children.
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