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List of top nine psychological experiments on learning!
Experiment # 1. Conditioning-Finger Withdrawal:
Introduction:
One of the important concepts in modern psychology is the concept of conditioning originally introduced by the Russian physiologist, Pavlov. This concept refers to the nature and origin of connections between stimulus and response. It was generally believed before Pavlov that specific responses of organisms could be aroused by only specific stimuli.
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To put it in other words, it was believed that there were inherent bonds or connections between specific natural responses and specific environmental stimuli; for example, the response of salivation could be produced only by the sight of food Pavlov’s experiments showed that this was not the case and any specific response within limits could be connected to a wide variety of stimuli not having any natural stimulus value.
Through this classical experiment he showed that a dog would salivate even at the sound of a bell. The process of connecting an unnatural and new stimulus to a response with which it had originally had no connection is known as conditioning.
Since the time of Pavlov, several experiments have been carried out on different aspects of the phenomenon of conditioning, the laws governing the factors of influencing, etc. Several other phenomena, like the removal of an established conditioned response, its generalisation, etc., too have been demonstrated. Later workers like Hull, Skinner, Guthrie, Tolman and others have introduced new concepts in studying this process.
Problem:
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To demonstrate the phenomenon of conditioning by establishing a conditioned finger withdrawal response.
Materials Required:
A finger withdrawal apparatus; Kymograph; recording device.
Finger withdrawal apparatus consists of a wooden box with a metallic plate on which the subject has to place his palm keeping the middle finger raised and touching a metallic rod suspended ever the plate. This metallic rod is connected to a tambour which in turn is connected through a fine rubber tube to a rotating kymograph. The metallic plate is electrically connected to the main or the battery so that the subject is given mild electric shocks as unconditioned stimuli.
When the subject receives a shock, he withdraws his finger which produces a jerk on the metallic rod. The extent of this jerk is recorded through the recording tambour. In addition to this arrangement, there is a bell and light either of which can be used as a conditioned stimulus. There is a screen which divides the experimenter’s side from the subject’s side. On the experimenter’s side are switches to manipulate the bell, the light and the shock stimulus.
Procedure:
The subject is seated comfortably and instructed to place his palm on the metallic plate and raise his middle finger in such a way that it is in contact with the metallic rod. The experimenter uses either the light or the bell as the conditioned stimulus.
1. Switch on the light and at the same time administer the shock also. The subject will withdraw his finger. Continue to do this. On some of the occasions switch on only the light and do not administer the shock. This must be done in accordance with a prepared schedule.
The procedure is continued until the subject withdraws his finger on three consecutive experimental trials (trials where the light stimulus is not followed by the stimulus shock). The first of these three consecutive trials indicates the point where conditioning has been established.
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2. Proceed with the experiment using only the experimental trials. Note down the frequency of experimental trials responded to with withdrawal.
Results:
1. Calculate the number of trials required for establishing conditioned response.
2. Calculate the number of trials required to remove the conditioned response after it has been established as conditioned.
3. Study the kymograph record produced and note how the intensity of the conditioned response changes before and after it has been established.
4. Collect the data for the group and discuss the individual differences.
Note:
This experiment can be repeated with a bell as the conditioned stimulus. Similar experiments can also be conducted with hand- withdrawal, blink and knee-jerk responses, etc.
Experiment # 2. Trial and Error (Learning a Simple Motor Skill):
Introduction:
The first systematic formulation of a learning theory was put forward by Thorndike. According to this theory, all human learning proceeds by trial and error, i.e., in the beginning the learner makes a lot of effort and by accident discovers the correct response. Gradually, with repeated performance the wrong efforts are eliminated and the right moves are established.
To explain this process of elimination and fixation, Thorndike formulated three laws:
1. Law of Exercise:
According to this law, those acts or moves which are repeated more frequently in the process of learning tend to get established.
2. Law of Recency:
According to this law, those moves which have occurred more recently in time tend to recur more easily.
3. Law of Effect:
This is probably the most important law, according to which those moves which are followed by satisfaction are ‘stamped in’ while those moves which do not lead to satisfaction are ‘stamped out’. This phenomenon was later elaborated by Hull as the principle of reinforcement. Several psychologists, like Kohler, however, have shown that simple trial and error cannot explain all learning. At best, this can explain only the learning of simple motor skills.
Problem:
To demonstrate the phenomenon of trial and error in acquiring a new motor skill.
Materials:
A mirror drawing board, a stopwatch, batteries, impulse counters, stylus.
The mirror drawing board, originally designed by Starch consists of a wooden board with a metallic plate which has star patterned groove in the middle. Over the metallic plate should be a mirror.
The screen is kept in a particular position, the subject will be unable to directly see the star pattern but will be able to see its image in the mirror. The board is connected to a battery, an impulse counter and stylus. Whenever the free needle of the stylus touches the metallic edges of the star pattern, the circuit is closed and the counter records one impulse.
Procedure:
1. Instruct the subjects as follows- ‘Look at this mirror, you will see a star image. The star image is a reflection of a pattern on the wooden board and concealed by the screen. Take the stylus in your hand (the experimenter gives the stylus to the subject and helps him to position it at the end of the groove. Now you will have to look into the mirror image and trace the star pattern with the stylus. Take care that the stylus should not touch the edges of the groove. If you touch, it will be counted as an error. You will have, to start all over again and can stop only after you have succeeded in tracing the star without touching the edges. Try to do it as speedily as possible.’ The experimenter gives one or two demonstrations.
2. The experimenter says ‘ready’ and at the same time starts the stopwatch. When the subject completes the first tracing, stop the watch and note the time taken. Also note the number of errors, recorded on the counter.
3. Ask the subject to repeat the experiment. Again note the time taken and the errors committed.
4. Make the subject repeat the process ten times.
Tabulate the results as follows:
1. Observe the results and find out how the time and number of errors decrease as the trials increase. See whether the decrease is gradual or sudden. Plot the time and errors on a graph.
2. Collect the data for the entire group and tabulate the results as follows:
3. Study the individual variations.
4. For the different trials, draw time and error graphs for the group averages.
5. Compare this with the graph for your individual subject.
Experiment # 3. Insight into Motor Learning:
Introduction:
The previous experiment served to illustrate how a simple motor skill is learnt by the process of trial and error. However, it must be pointed out that all major learning does not entirely occur on the basis of trial and error. Sometimes, when an individual is able to formulate certain regular principle, motor learning shows very sudden improvements not explicable by the usual trial and error theory.
This can be illustrated by the following experiment:
Problem:
To illustrate the role of insight in motor learning.
Materials:
A step maze with two pathways, battery, bulbs, stopwatch and stylus.
Description of the Step Maze:
A step maze is made of different patterns; usually it consists of a wooden box having rows of metallic screw-heads on top. The box can be opened with a hinge arrangement. On the inside, the concealed ends of some screws are connected with each other in two pathways, extending from the first two to the last row along the length of the box.
In one pathway the screws are connected in a haphazard way, may be the first two in a straight line, the next four to the left, the next two to the right, etc. The second pathways’ connection follows a regular principle, which makes it easier to grasp and therefore, the understanding is much easier.
The essence of the experiment is that the subject has to learn these two pathways when the maze is closed. The step maze is connected to a red bulb in the circuit through battery and to the stylus.
Whenever the subject touches one of the connected screws with the stylus the light will glow. This is an indication that he is touching the correct screw. If, however, he touches one of the screws not connected in the pathway no light will glow. It is sometimes advantageous to connect the wrong screws in another circuit with a buzzer so that whenever these screws are touched the buzzer rings.
Procedure:
Make the connections, close the maze and seat the subject close to the starting point of the first (path ‘A’). Give him the stylus and place his hand on the first screw of the path A’.
Instructions:
1. Your stylus is at the starting point. The finishing point is at the other end. (Point out the finishing point). You will have to trace the path with the stylus by touching a certain set of screws and bring your stylus to this finishing point. Take care that the stylus should touch only the correct screws. Whenever you touch a correct screw this light will glow. If the light does not glow it means you have gone out of the right path. The experimenter gives some demonstrations of how correct steps are to be identified by touching only one or two screws.
2. The experimenter says ‘ready’ and starts the stopwatch. He makes a careful note of the number of wrong screws which the subject touches. As soon as s/he reaches the finishing point the time taken is noted and the number of wrong screws touched is also noted down. This procedure is repeated until the subject masters the path.
3. The experiment is now repeated with the regular pathway. (Path ‘B’)
Results:
As in the previous experiment the time taken and the errors are tabulated:
1. Compare the decrease in time and errors for the two paths. In the case of ‘B’ you will find that after some trials, there is a sudden decrease in both time and errors. This is because the subject has grasped the basic principle of direction and number of steps underlying this path. This is called learning by insight.
2. Collect the group data for the two pathways as in the previous experiment. Analyse the results.
3. Represent individual and group data graphically, compare the graphs.
Experiment # 4. Effect of Punishment on Learning:
Introduction:
The idea that learning is facilitated by punishment has been held throughout history and several systems of punishment have been developed out of this. Thorndike in his theory of ‘trial and error’ had stated that moves leading to an annoying state of affairs tend to be eliminated.
Since punishment introduces an annoying state of affairs, it can be expected to produce an elimination of the wrong moves. Psychologists working from the point of view of the theory of conditional reflexes studied this phenomenon under the name of avoidance conditioning.
Problem:
To study whether punishment facilitates the acquisition of motor skill.
Materials Required:
A mirror groove apparatus connected to the battery, an impulse counter and a stylus as in the experiment of trial and error. In addition, a shock coil and an inductorium are introduced in the circuit and a stopwatch too is required.
Experimental Psychology:
Procedure:
The present experiment is done as a group experiment. Two groups of subjects are chosen matched in age, intelligence, educational level and sex. One of the groups is the controlled group which learns without punishment and the second one the experimental group which learns with punishment.
1. Procedure for the Controlled Group:
The procedure for the experiment is trial and error. For this group, the shock coil and inductorium are not included in the circuit.
Conduct the experiment on the controlled group and tabulate the results as follows:
2. Procedure for the Experimental Group:
For this group, the inductorium and the shock coil are introduced in the circuit. The instructions also vary slightly. The additional instruction is as follows- ‘When you trace the mirror pattern with one hand, keep the other hand on this coil.’ (Point to the shock coil).
Here the subject whenever he makes a mistake, gets a mild shock and this is the punishment. Excepting for this, the procedure is the same as for the controlled group. Tabulate the results as in the case of the controlled group above.
Results:
Tabulate the results of the two groups as shown:
Calculate the means, standard deviations and standard errors for both the groups for all the five variables listed above. Test the significance of difference between the groups on all the five variables. Which group is better?
Experiment # 5. Role of Emotional Factors in Learning:
Introduction:
For a long time it was not recognised that a person’s feelings and emotions would influence the process of learning. With the advent of psychoanalysis and the concept of the unconscious mind, it has been found that material which is likely to arouse certain emotions and needs of the individual is likely to require greater effort of learning.
Problem:
To compare the speeds of learning for emotional and neutral words.
Materials Required:
Memory drum- a list of ten emotional words and a list of ten neutral words.
The emotional words must be chosen carefully such that they are likely to arouse the emotions of the subjects e.g., girl, sex, murder, etc. Examples of neutral words are road, buildings, etc.
Procedure:
The procedure and instructions are exactly the same as for the experiment on meaningful and meaningless materials. The two lists of words are presented through a memory drum as many times as necessary for the subject to be able to reproduce the two lists.
Results:
Tabulate the results for the group as follows:
Compare the number of trials required for the two lists and test the significance of difference.
Experiment # 6. Effect of Knowledge of Results on Learning:
Introduction:
It has been found by a number experimenters that an individual’s rate of acquisition of a particular skill is affected by his/her knowledge of results. This was clearly demonstrated through some experiments conducted by the US army and airforce. Knowledge of the results can affect the learning process in two ways.
On the positive side, the knowledge of earlier successes may motivate the individual to better learning. If, however, there are too many failures, these may lead to discouragement and fall in the rate of learning. Further, the knowledge of results also facilitates readjustment.
Problem:
To find out whether the knowledge of the results of one’s progress in learning a skill effects the rate of learning.
Materials:
A target in the form of a bull’s eye, a pencil, a scale, a blindfold.
Procedure:
The experiment is done as a group experiment. The common game of hitting the bull’s eye can be employed. The group is divided into an experimental group which works with the knowledge of the results and a controlled group which works without the knowledge. For the controlled group, the procedure is as follows.
Each subject of this group is blindfolded and is required to touch the eye of the bull with the pencil. Every time he/she attempts to touch it, the error is measured with the help of the scale and noted down. He/she is allowed to have a maximum of 15 trials. If however, the subject succeeds in getting two successive right touches, the experiment is stopped even earlier.
For the experimental group, the procedure is similar, excepting that after every attempt the subject is informed as to the extent and direction of the errors. Again a maximum of 15 trials is given. If the subject learns earlier, the experiment is stopped as soon as the subject succeeds even before the 15 trials are completed.
Results:
Calculate the average error for each trial for experimental and controlled groups separately as follows:
Plot the results for the two groups in the form of two graphs and compare the progress of learning. Does the experimental group show any superiority?
Experiment # 7. Transfer of Learning:
Introduction:
One of the burning topics of research in the field of psychology of learning has been the problem of transfer of learning from one situation to another. For a long time, it was thought that some materials may be easier to learn after grasping of certain other materials. This belief was reflected in the idea of formal discipline in the educational programme where study of classical languages like Latin was supposed to improve the ability for learning certain other subjects. Transfer can be of two types- positive or negative.
Sometimes, learning a skill may make it easier to learn the subsequent skill. In other instances, learning one skill actually may make it difficult to learn a subsequent skill. Both types of transfers have been experimentally demonstrated.
One important type of experimentation is ‘fore and after’ test method. In this, the subjects perform one task ‘A’ for some time and before and after this, their performance in task ‘B’ is noted to find out whether there is any difference in the two performances resulting form learning ‘A’.
However, a better procedure is to employ two groups- one controlled and another experimental group. This procedure was employed by Woodworth and Thorndike, Wich, Dearborn and others. Another method is the successive-practice method. Here the procedure is for the same subject to learn two equivalent tasks ‘A’ and ‘B’ successively. If learning, ‘B’ is found to be easier than learning ‘A’, then transfer is supposed to have taken place.
Problem:
To demonstrate the phenomenon of bilateral transfer by the ‘fore after’ technique.
Materials Required:
A mirror tracing board with batteries, impulse counter and a stylus.
Procedure:
The subjects are to be divided into two matched groups on the basis of their performance on the fore test (tracing of the star pattern with the left hand for the first time). Again, by one of the methods of randomisation, divide these groups into experimental group and the control group.
(i) Control Group:
Give the following instructions to the subjects included under the Control Group:
“Look at this mirror, you will see a star image. The image is a reflection of a pattern on the wooden board and is concealed by the screen. Take the stylus in your left hand (The experimenter gives the stylus to the subject and helps him to position it at the end of the nearest position). Now you will have to look into the mirror image and trace the star pattern with the stylus. Take care that the stylus does not touch the edges of the groove. If it does, it will be counted as an error. Try to trace the image as speedily as possible”.
After the subject traces the path once with the left hand, he is asked to trace the path again for the second time. Time taken and the number of errors committed are noted down when the subject traced the path with left hand for the first time (Fore test) and also for the second time (After test).
(ii) Experimental Group:
The same instructions are to be given to the subjects included under the experimental group also. The only difference between the control group and the experimental group is that the subjects in the latter group practice the tracing of path with the right hand for about 10 trials while the subjects in the control group do not do so.
In the case of the experimental group the fore test corresponds to the tracing of path with the left hand for the first time before practicing with the right hand, and after test corresponds to the tracing of the path again with the left hand after the practice period.
The time taken and the number of errors committed are noted down during the fore test and the after test and the performance of the control and experimental groups in the fore test and the after test are tabulated as below:
Results:
(1) Calculate the percentage gain in time from the fore test to after test in control group as well as in the experimental group. Calculate CR for determining the significance of difference between these percentages.
(2) Calculate the percentage of the reduction in the number of errors from fore test to after test in Control Group and Experimental Group. Calculate CR for determining the significance of difference between these percentages.
Discussion:
If the CR value is significant in favour of the experimental group, then the phenomenon of positive bilateral transfer is confirmed. If the CR value is significant in favour of the Control Group, then the phenomenon of negative bilateral transfer is confirmed. If the CR value is insignificant, then the phenomenon of bilateral transfer is not confirmed.
Experiment # 8. Transfer in Verbal Learning:
Problem:
To study the effect of similarity of material on transfer in verbal learning.
Materials Required:
Two poems X and Y, a passage from prose, a list of numbers consisting of 4 digits each.
Procedure:
This experiment is carried out as a group experiment. A group of subjects, say, twenty four subjects are categorised into four groups A, B, C & D following the method of randomisation.
Group A learns poem X, group B learns the prose passage, group C learns the list of numbers and group D does not learn initially anything during the experiment. This group serves as the control group while the three other groups A, B & C serve as experimental groups. Later, all the four groups are instructed to learn poem Y. The number of trials required by each subject to learn perfectly the poem Y is to be noted down and the results are to be tabulated.
Mean number of trials taken by each of the experimental groups and the control group to learn perfectly the poem Y, are tabulated as follows:
Results:
Determine the significance of difference between the means of every pair of the above groups by computing ’t’ ratios and discuss the following points:
1. Whether the mean number of trials taken by each of the experimental groups is less than that of the control group.
2. Whether the mean number of trials taken by the experimental group ‘A’ is less than that of the experimental groups B and C and the control group.
Experiment # 9. Whole Vs. Part Learning:
Introduction:
While learning any material, for example a prose passage, some people adopt the method of learning one part thoroughly and then going to the next part, thus learning the whole passage part by part. This is called the part method. Some others, on the other hand, prefer to go through the entire passage repeatedly and try to learn the passage as a whole. In a very early experiment Stiffens found that in learning syllables and stanzas the whole method was found to take much less time. Pyle and Snider in their experiments also found a distinct advantage in using the whole method.
Similar results were also obtained by Mailer. However, Winch in an experiment on learning poetry found part learning to be more advantageous. McGoech in a study on children found little difference between the two methods. Cook, using mazes, and human subjects again found little difference between the two methods. One thus finds that the conclusions here are contradictory. The fact is that ease of learning appears to depend not only on the method but also on the ability of the subject, the difficulty of the materials, the length of the material etc.
Problem:
To compare the relative advantages of the whole and part methods in learning a passage of poetry.
Materials:
A poem consisting of three or four stanzas.
A. Procedure for the Whole Method:
The experiment is done as a group experiment. Two groups of subjects of equal intelligence are chosen, one being subjected to the whole method of learning and another to the part method. The experiment is done in separate rooms on the two groups.
1. Instruction to ‘ the whole ‘ learning group- ‘I will read out a poem to you. You will have to listen carefully and write down. This procedure will be repeated ten times, which means that you will write down the poem ten times.’
2. The experimenter reads the passage in a clear and audible way and asks the subject to write it down.
3. This procedure is repeated ten times. At the end of this, the last reproductions are corrected and the number of errors counted.
B. Procedure for the Part Method:
1. Here the instructions are as follows- ‘I have a poem consisting of three stanzas. I will read out one stanza and you will have to write down what I have read. The same stanza will be read out ten times and you will have to write down. You will follow the same method in regard to all the three stanzas’.
2. The experimenter reads out the first stanza ten times each time asking the subject to write it down. The same procedure is repeated with the other stanzas also.
Finally the subjects are required to reproduce the entire poem. These reproduction are corrected and the mistakes counted.
Results:
Tabulate the results as follows:
Test the significance of difference in mean errors by employing the t-ratio.
Note:
Repeat the experiment with greater digits of numbers, longer poetic passages , lists of nonsense syllables, etc., and find out how the length, type of materials, etc., affect the results.
Practical Application:
Such experiments help the student to plan his methods of study. It also helps the teacher to decide whether he should teach a particular material in part or as a whole.