Chapter 2 - The Study of Learning and Behaviour Flashcards
(15 cards)
Explain the meaning of Thomas Henry Huxley’s opening quote. (p. 35)
Comment: Huxley’s quote strikes at the heart of what it means to be a scientist, especially a behavioural scientist. The ability to be guided by one’s observations above all else is essential to scientific progress.
“Sit down before fact as a little child, be prepared to give up every preconceived notion, follow humbly wherever and to whatever abysses nature leads, or you will learn nothing.”
—T. H. Huxley
Describe the law of parsimony. How does it relate to explanations of behaviour that rely on hypothetical events? (pp. 35–36)
The simplest explanation that fits the data is best. This is a fundamental tenet of all sciences known as the law of parsimony. It means that the fewer assumptions (unverified events) required by an explanation, the better.
Describe the following ways of measuring learning: reduction in errors, changes in topography, changes in intensity, changes in speed, changes in latency, and changes in rate or frequency. Provide original examples of each. (pp. 37–41)
Errors. A common way of measuring learning is to look for a reduction in errors. A rat can be said to have learned to run a maze to the extent that it goes from start to finish without taking a wrong turn. As training progresses, the rat will make fewer and fewer errors. Similarly, a student is said to have learned a spelling list when she can spell all the words without error.
Topography. Learning may be measured as a change in the topography of a behavior, which refers to the form a behavior takes. Topography may be used as a measure of learning in mirror tracing. The task is to trace a form while looking at its reflection in a mirror. It is harder than it seems, and at first the pencil line meanders wildly. With practice, however, a person can trace the shape rather neatly. The change in topography is a measure of learning.
Intensity. We can also measure learning by noting changes in the intensity of a behavior. When a laboratory rat learns to press a lever, the resistance of the lever may be increased so that greater force is required to depress it. The increase in pressure exerted by the rat is a measure of learning.
Speed. A change in the speed with which a behavior is performed is another measure of learning. The rat that learns to run a maze reaches the goal faster than an untrained rat. In the same way, a first grader takes a long time to recite the alphabet at the beginning of the year but later runs through it with the speed of an auctioneer.
Latency. A similar measure of learning is a change in latency, the time that passes before a behavior occurs. A student beginning to learn the multiplication table pauses before answering a question such as “How much is 5 times 7?” With practice, the pauses become shorter, and eventually the student responds without hesitation.
Rate. Learning is often measured as a change in the rate at which a behavior occurs. A person may practice receiving Morse code by telegraph. If the rate of decoding (the number of letters correctly recorded per minute) increases, we say that he has learned.
What is fluency? Provide an original example. (p. 41)
Fluency. Fluency is a measure of learning that combines errors and rate; it is the number of correct responses per minute. For example, a student who calls out the answers to single-digit addition problems (such as 9 + 4, 7 + 3, and 5 + 9) provided by a teacher, may call out 12 answers in one minute. If 10 of those answers are correct, then his fluency measure is 10 correct per minute. If, after instruction or practice, his fluency rate is 22 correct per minute, that provides a clear measure of learning.
What are the problems with using case studies as a source of evidence? What advantages do case studies have over anecdotal evidence? (pp. 42–43)
Comment: One problem with psychology textbook criticisms of anecdotal evidence is that they portray those using anecdotal evidence as foolish, assuming that better evidence is available. They fail, however, to acknowledge that there are no sources of pristine scientific data available for making many day-to-day decisions. For example, selecting a marriage partner is undoubtedly a significant decision, but it isn’t feasible or practical to do experimental research on prospective partners to select the most suitable one. The issues surrounding the use of anecdotal evidence in day-to-day life have not been properly understood within psychology.
Anecdotes are first or secondhand reports of personal experiences.
We get a slightly better grade of data with the case study. Whereas anecdotal evidence consists of casual observations, a case study examines a particular individual in considerable detail.
There are, however, serious problems with case study evidence. One problem is that doing a case study takes a good deal of time. Because of this, generalizations are often based on very few cases. If those few cases are not representative of the larger group, conclusions about that group may be in error.
Another problem is that the case study cannot answer certain questions about behavior. We cannot, for example, use the case study to determine whether falling off a ladder is likely to produce a fear of heights. We may interview a person who fell off a ladder and who subsequently developed a fear of heights, but this does not establish that the fall caused the fear. For years, many clinical psychologists and psychiatrists insisted that homosexuality was a neurotic disorder because their homosexual clients were all neurotic. Then, in the 1950s, Evelyn Hooker pointed out that the heterosexual clients of clinicians were also neurotic, but no one concluded that heterosexuality was a form of neurosis.
Case study evidence is also flawed in that much of the data obtained comes not by direct observation of the participant’s behavior, but from what the participant or other people report about the participant’s behavior. Such reports are notoriously unreliable.
When appropriate, the case study is a step above the anecdote because at least the data are obtained in a fairly systematic way.
What are the advantages and disadvantages of descriptive studies? (p. 44)
By gathering data from many cases and analyzing the data statistically, the descriptive study reduces the risk that a few unrepresentative participants will lead to false conclusions.
Descriptive studies represent a vast improvement over case studies, but they have their limitations. One is that although descriptive studies can suggest hypotheses to explain a phenomenon, they cannot test those hypotheses. We might find that phobia victims are twice as likely as others to describe their parents as overprotective, yet overprotective parenting may not be important in producing phobias. It could be, for example, that overprotective parenting is associated with some other variable, such as a genetically based high level of anxiety, and this other variable is what accounts for the higher incidence of phobias.
Define independent and dependent variables. Provide original examples of each. (pp. 44–45)
The variables the researcher manipulates are called independent variables; those that are allowed to vary freely are called dependent variables.
Describe a between-subjects experiment using an example. Why is it appropriate to use a random assignment in such experiments? (pp. 44–46)
In between-subjects experiments, the researcher typically identifies two or more groups of participants. The independent variable is then made to differ across these groups.
The validity of experimental results rests on the extent to which the participants being compared are alike. Through random assignment, any differences among the participants should be distributed more or less equally among the groups.
What is a within-subject experimental design? Define a baseline period and an ABA reversal design. Provide an original example of a within-subject experimental design in the form of an ABA reversal design. (pp. 46–48)
The alternative to the between-subjects design is the within-subject experiment. In these experiments, a participant’s behavior is observed before the experimental treatment and then during or after it.
The initial period during which a participant’s behavior is observed is known as the baseline period because it provides a basis for comparison.
In figures depicting within-subject data, this period is usually labeled “A.” The treatment period follows the baseline and is labeled “B.” If the A and B periods yield different results (e.g., different latencies or different rates of behavior), this should be apparent in the data graph.
Because the independent variable varies within the same person or animal, concern that the results might be due to differences among participants is greatly reduced. However, it is possible that some extraneous variable is responsible for the results. An animal could become ill during an experiment, for example, and this could give the illusion that the experimental treatment had changed the participant’s behavior when, in fact, it had not. To rule out such possibilities, the experimenter may return to the baseline (A) condition in what is known as an ABA reversal design.
Compare and contrast within subjects and between-subjects experimental designs. (p. 48)
Although within-subject experiments and between-subjects experiments differ in the number of participants and in the use of statistics, these are not the most important differences between them. A far more important difference has to do with the way in which extraneous differences among participants are controlled. In between-subjects experiments, these differences are controlled chiefly through random assignment and matching. The assumption is that important differences among participants will “even out” across the groups. In within-subject experiments, extraneous differences among participants are controlled by comparing participants against themselves. The assumption is that if the same participant is observed under experimental and control conditions, extraneous differences among participants are largely irrelevant.
What is the chief limitation of experimental research? Define laboratory and field experiments and compare and contrast them. How does the use of field experiments help to overcome the main limitation of experimental research? (pp. 48–49)
The great power of the experiment comes from the control it provides over variables. However, this very control has led to the criticism that experiments create an artificial world from which the researcher derives an artificial view of behavior. Some people have a hard time believing that the artificial world of the experiment can tell us anything important about behavior in natural environments.
Laboratory experiments offer the control that allows the researcher to derive clear-cut principles.
Field experiments - those done in natural settings - allow the researcher to test laboratory-derived principles in more realistic ways.
Identify and explain the three major reasons for using animals in research on learning. (pp. 49–50)
First, animals make it possible to get control over the influence of heredity. We cannot, of course, have breeding programs to produce people with uniform genetic backgrounds.
Second, with animals it is possible to control a participant’s learning history. Animals can be housed from birth in environments that are far less variable than their natural environments, thus greatly reducing the influence of unintended learning experiences.
Third, it is possible to do research with animals that, for ethical reasons, cannot be done with people. It might be interesting and useful to know whether a certain kind of experience would make people depressed or induce them to attack their neighbors, but doing such research with people raises serious ethical problems.
What is the most common objection to using animals in research on learning? Are there valid grounds for this objection? Explain. Identify two additional objections to using animals in research and the counter-arguments to these objections. (pp. 50–52)
Perhaps the objection heard most often is that the results obtained tell us nothing about people. Critics complain, “People are not rats!” or “Just because pigeons behave that way, doesn’t mean that I behave that way.”
A second objection to animal research is that it has no practical value. Unlike the biomedical research that uses animals to determine the health risks of smoking, this argument goes, animal research on behavior merely provides facts that only a theoretician could find useful. It is true that animal research is sometimes aimed at answering esoteric theoretical questions, but the findings of this research often have great practical value. Principles derived from animal research have been put to good use in numerous areas, including child rearing and education.
A third objection to animal research is that it is intrinsically unethical. This “animal rights” view maintains that people have no more right to experiment on rats than rats have to experiment on people. But critics of animal research ignore the fact that ethical issues arise when we use animals for other purposes besides research. If it is unethical to use animals for research, is it ethical to eat them? Do people have the right to conscript animals for farm work, such as hauling heavy loads and plowing fields?
Discuss the guidelines set out by the American Psychological Association for research on animals. (p. 52)
In an effort to prevent unnecessary suffering, the American Psychological Association (2010) and other organizations have established guidelines for the conduct of animal research. These require that certain standards be met in the care and handling of animals. Animals may, for instance, be made to “work” for their food; but the amount of work is typically far less than that required of animals in domestic service or living wild. The guidelines also set standards for the use of aversives (stimuli the animal would avoid, given the option). If a question can be answered without the use of aversives, they are not to be used. When aversives are deemed necessary, they must be no more severe than is required by the nature of the research. The use of aversives must also be justified by the probable benefits to be gained from the research.
What is the major criticism regarding the use of computer simulations to replace animals in research? (p. 52)
We cannot program a computer to simulate the effects of a variable on behavior until we know what those effects are. That is precisely what research is designed to discover.
