C.L. Hull - learning theory

C.L. Hull - learning theory

INTRODUCTION

Learning is one of the most important topics in present-day psychology, yet it is an extremely difficult concept to define. Learning occupies a very important place in our life. Most of what we do or do not do is influenced by what we learnt it. Learning therefore provides a key to the structure of our personality and behavior. An individual starts to learning immediately after his birth or in a strict sense even in womb of the mother. Experience direct or indirect is found to play a dominant role in molding and shaping our behavior of the individual from the very beginning. The change in behavior brought about by experience is commonly known as learning. In this way, the term learning broadly speaking, stands for all those changes and modifications in the behavior of the individual which he undergoes during his life time.

DEFINITION

Gardner Murphy (1968)

The term learning covers every modification in behavior to meet environmental requirements.

Henry P. Smith (1962)

Learning is the acquisition of new behavior or the strengthening or weakening of old behavior as the result of experience.

Crow and Crow (1973)

Learning is the acquisition of habits, knowledge and attitudes. It involves new ways of doing things, and it operates in an individual’s attempts to overcome obstacles or to adjust to new situation. It represents progressive changes in behavior. It enables him to satisfy interests to attain goals.

Kimble (1961)

Learning is a relatively permanent change in behavioral potentiality that occurs as a result of reinforced practice.

The above definition reveals the following facts:

1.      Learning is a process and not a product.

2.      It involves all those experience and training of an individual (right from birth) which help him to produce changes in his behavior

3.      Learning leads to changes in behavior but this does not necessarily mean that these changes always bring about improvement or positive development. One has an equal chance to drift to the negative side of human personality.

4.      Learning prepares an individual for any adjustment and adaptation that may be necessary

ABOUT THE AUTHOR

C.L HULL

Time Line

1884 Hull was born
1918 Received Ph.D. from University of Wisconsin
1933 Hypnosis and Suggestibility, published
1940 Mathematico - Deductive Theory of Rote Learning: A study in Scientific Methodology was published.
1943 Principles of Behavior was published
1951 The Essentials of Behavior was published
1952 A Behavior System was published
1952 Hull died

Life history

Clark Leonard Hull was born in Akron, New York (May 24, 1884 – May 10, 1952). He was an influential American psychologist and learning theorist in behaviorism. He sought to explain learning and motivation by scientific laws of behavior. Clark Hull's most important contribution to psychology lies in his theory of learning, considered one of the most important learning theories of the twentieth century. He also conducted research demonstrating that his theories could predict and control behavior, and inspired many of his students to continue to develop his theories and maintain his high standards of scientific method in the field of psychology.

Clark Hull grew up handicapped and contracted polio at the age of 24, yet he became one of the great contributors to psychology. His family was not well off so his education had to be stopped at times. Clark earned extra money through teaching. Originally Clark aspired to be a great engineer, but that was before he fell in love with the field of Psychology. By the age of 29 he graduated from Michigan University. When Clark was 34 when he received his Ph.D. in Psychology at the University of Wisconsin in 1918. Soon after graduation he became a member of the faculty at the University of Wisconsin, where he served for 10 years. Although one of his first experiments was an analytical study of the effects of tobacco on behavioral efficiency, his lifelong emphasis was on the development of objective methods for psychological studies designed to determine the underlying principles of behavior.

Hull devoted the next 10 years to the study of hypnosis and suggestibility, and in 1933 he published Hypnosis and Suggestibility, while employed as a research professor at Yale University. This is where he developed his major contribution, an elaborate theory of behavior based on Pavlov's laws of conditioning. Pavlov provoked Hull to become greatly interested in the problem of conditioned reflexes and learning. In 1943 Hull published, Principles of Behavior, which presented a number of constructs in a detailed Theory of Behavior. Soon he became the most cited psychologist. For his effort, Hull received the Warren medal in 1945 from the society of Experimental Psychology. Hull was physically disabled most of his life. In 1948 he had coronary attack, and four years later he died. In his last book he wrote (A behavior system), he expressed regret that the third book that he had intended to write on learning would never be written.

HULL LEARNING THEORY

1.     DERIVE REDUCTION THEORY

Drive Reduction Theory -(Hull)- the notion that behavior occurs in response to "drives" such as hunger, thirst, sexual interest, feeling cold, etc. When the goal of the drive is attained (food, water, mating, warmth) the drive is reduced, and this constitutes reinforcement of the behaviors that lead to the drive reduction, and ultimately learning.

Hull viewed the drive as a stimulus, arising from a tissue need, which in turn stimulates behavior. The strength of the drive is determined upon the length of the deprivation, or the intensity / strength of the resulting behavior. He believed the drive to be non-specific, which means that the drive does not direct behavior rather it functions to energize it. In addition this drive reduction is the reinforcement.

Hull's learning theory focuses mainly on the principle of reinforcement; when an S-R relationship is followed by a reduction of the need, the probability increases that in future similar situations the same stimulus will create the same prior response. Reinforcement can be defined in terms of reduction of a primary need. Just as Hull believed that there were secondary drives, he also felt that there were secondary reinforcements - “If the intensity of the stimulus is reduced as the result of a secondary or learned drive, it will act as a secondary reinforcement" (Schultz & Schultz, 1987, p 241). The way to strengthen the S-R response is to increase the number of reinforcements, habit strength.

1.      Change in the traditional S-R notion

Hull introduced concept of intervening variables between S and R. Accordingly, when a stimulus(S) impinges on the organism, it results in a sensory neural impulse(s) a kind of stimulus trace. This stimulus trace ultimately causes a motor neural reaction(r) those results in an overt response (R). Thus we may have the formula S-s-r-R instead of the traditional   S-R. However, there are so many other things within the inner mechanism of the organism like his interest, needs and drives also the reinforcing mechanism that may influence his response or behavior.

The link between the S-R relationships could be anything that might affect how an organism responds; learning, fatigue, disease, injury, motivation, etc. He labeled this relationship as "E", a reaction potential, or as sEr. Clark goal was to make a science out of all of these intervening factors. He classified his formula

sEr = (sHr x D ) - (sIr + Ir) - sOr

 Habit strength, sHr, is determined by the number of reinforces.

 Drive strength, D, is measured by the hours of deprivation of a need.                                   

Inhibitory strength, sIr, is the number of non-reinforces.

Reactive inhibition, Ir, is when the organism has to work hard for a reward and becomes fatigued.

The last variable in his formula is sOr, which accounts for random error.

Hull believed that this formula could account for all behavior,

2.    The concept of Drive Stimuli Reduction

Originally, Hull had a drive reduction theory of learning, but later he revised it to a Drive Stimuli Reduction theory of learning. One reason for the change was the realization that if a thirsty animal is given water as a reinforce for performing some act, it takes a considerable amount of time for the thirst drive to be satisfied by the water. The water goes into the mouth, the throat, the stomach, and eventually the blood. The effects of ingestion of water must ultimately reach the brain, and finally the thirst drive will be reduced. Hull concluded that the drive reduction was too far removed from the presentation of the reinforce to explain how learning could take place. What was needed to explain learning was something that occurred soon after the presentation of a reinforce, and that something was the reduction of drive stimuli (SD).

REASONS

1.      Drive stimuli for thirst include dryness in the mouth and parched lips. Water almost immediately reduces such stimulation thus hull had the mechanism he needed for explaining learning.

2.      It was provided by Sheffield and  Roby (1950), who found that hungry rats were reinforced by non- nutritive saccharine, which could not possibly have reduced the hunger drive.

Incentive motivation (K)

Results found by Crepsi and Zeaman led hull to reach the conclusion that organism learn as rapidly for a small incentive as they do for large one, but they perform differently as size of the incentive (K) varies. The rapid change in performance following a change in reinforcement size is referred to as the Crepsi effect, after the man who first observed it.

Stimulus-Intensity Dynamism

According to hull, Stimulus-Intensity Dynamism (V) is an intervening variable that varies along with the intensity of the external stimulus(S). Stated simply, Stimulus-Intensity Dynamism indicates that the greater the intensity of a stimulus, the greater the probability that a learned response will be elicited. Thus we must revise hull’s earlier formula as follows

sEr = (sHr x D x K x V) - (sIr + Ir) – sOr

It is interesting to note that because sHr , D,  K and V are multiplied together, if any one had a value of zero, reaction potential would be zero. For example there could have been many pairings between S and R (sHr), but if drive is zero, reinforcement is zero or the organism cannot detect the stimulus, a learned response will not occur.

Hull’s final system summarized

There are three kinds of variable in hull’s theory:

1.      Independent variable –which are stimulus events systematically manipulated by the experimenter.

2.      Intervening variables – which are process thought to be taking place within the organism but directly observable.

3.      Dependent variables – which are some aspect of behavior that is measured by  the experimenter in order to determine whether the independent variables had any effect.

EDUCATIONAL IMPLICATION

The development of curriculum

In this reference hull emphasized the importance of needs in learning process and accordingly the needs of all categories of children should be incorporated in the curriculum learning becomes meaningful only when it satisfies the needs of children.

The know actual needs of the students by teacher and parents

Hull is fells that teachers and parents of the student should also share their responsibility in teaching the actual needs of the student through various means proper guidance is must for their attitude and aptitudes.

Emphasized anxiety as a drive in human learning

From this line of reasoning, it follows that encouraging some anxiety in students that could subsequently be reduced by success is a necessary condition for classroom learning. Too little anxiety results in no learning (because there is no drive to be reduced), and too much anxiety is disruptive. Therefore, students who are mildly anxious are in the best position to learn and are therefore easiest to teach.

Hull’s system of learning advocated the following chain sequence for improved results in the teaching-learning process:

a.       Drive – This is something which is needed by the learner in order to behave or respond.

b.      Cue – There must be something to which the learner must respond.

c.       Response – The learner must be made to respond in order to learn some act.

d.      Reward – The learner’s response must be reinforced or rewarded, thus enabling him to learn what he wants to learn.

CONCLUSION

Hull’s system of learning is acclaimed and remembered for putting forward a most systematic, scientific and mathematical theory of learning. Hull was able to popularize a very innovative and objective behavioristic approach to learning which was more effective in comparison to the approach of his predecessors. The greatest contribution of hull’s theory lies in its emphasis on linking the learning to the needs of the children. He says that it is the need, drive or drive stimuli that energies an individual to act or learn or behave. Therefore, he advocated the need-based goals of education, including need-based curricula and methods of teaching. Whereas needs start the process of learning, reinforcement and incentives act as catalytic agents for increasing one’s efforts towards achieving the goals of learning. Therefore in any education process we must involve sufficient possibilities of proper motivation and reinforcement incentives.

SELF CHECK

1.      S.R refers to

a)  speaking-reading     b) stimulus-response   c) A and B       c) none of the above   

2.      Habit is strengthened by

a)      Number of trials    b) reinforcement         c) need                         d) A and C

3.      Hull was born in

a)      Asia                       b) Europe                     c) England       d) America     

4.      Intervening variables are directly

a)      Not observable     b) observable               c) occurred      d) not occurred

SHORT ANSWER

5.      State the theory of drive stimuli reduction.

6.      What are the educational implications of hull’s learning theory?

ESSAY TYPE

7.      Explain about the hull learning theory and its educational implication.