Thursday, March 28, 2013

What is cognitive psychology?


Introduction

Cognitive psychology is that branch of psychology concerned with human mental activities. A staggering array of topics fits under such a general heading. In fact, it sometimes seems that there is no clear place to end the catalog of cognitive topics, as mental operations intrude into virtually all human endeavors. As a general guideline, one might consider the subject matter of cognitive psychology as those mental processes involved in the acquisition, storage, retrieval, and utilization of information.







Among the more specific concerns of cognitive psychologists are perception, attention, memory, and imagery. Studies of perception and attention might be concerned with how much of people’s vast sensory experience they can further process and make sense of, and how they recognize incoming information as forming familiar patterns. Questions regarding the quality of memory include how much information can be maintained, for how long, and under what conditions; how information is organized in memory and how is it retrieved or lost; and how accurate the memory is, as well as what can be done to facilitate a person’s recall skills. Cognitive researchers concerned with imagery are interested in people’s ability to “see” in their minds a picture or image of an object, person, or scene that is not physically present; cognitive researchers are interested in the properties of such images and how they can be manipulated.


In addition to these concerns, there is great interest in the higher-order processes of planning, reasoning, problem solving, intelligence, language, and creativity. Cognitive psychologists want to know, for example, what steps are involved in planning a route to a destination or a solution to a problem, and what factors influence people’s more abstract ability to reason. They seek to understand the importance of prior knowledge or experience, to discover which strategies are effective, and to see what obstacles typically impede a person’s thinking. They are interested in the relationships between language and thought and between creativity and intelligence.


The following exchange is useful in illustrating some of the topics important to cognitive psychologists. Imagine that “Jacob” and “Janet” are two children on a busy playground:

Jacob: Do you want to play some football?

Janet: Sure! Tell me where the ball is and I’ll go get it.

Jacob: The football’s in my locker in the equipment room. Go back in the building. Go past our classroom, turn right at the water fountain, and it’s the second door on your left. My locker is number 12, and the combination is 6-21-13.

Janet: Okay, it’ll just take me a couple of minutes. [As she runs to get the ball, Janet repeats over and over to herself, “12; 6, 21, 13. . . . ”]

Jacob: [shouting] The football field’s being watered; meet me in the gym.


Even such a simple encounter involves and depends on a rich assortment of cognitive skills. At a basic level, Jacob and Janet have to be aware of each other. Their sensory systems allow the detection of each other, and their brains work on the raw data (information) from the senses to perceive or interpret the incoming information. In this case, the data are recognized as the familiar patterns labeled “Jacob” and “Janet.” During the course of the brief conversation, the children must also attend to (concentrate on) each other, and in doing so they may be less attentive to other detectable sights and sounds of their environment.


This scenario illustrates the use of more than one type of memory. Janet stores the locker number and combination in short-term memory (STM), and she maintains the information by rehearsing it. After Janet retrieves the ball and redirects her attention to choosing teams for the football game, she may forget this information. Jacob does not need to rehearse his combination continually to maintain it; rather, his frequent use of his combination and the meaningfulness of this information have helped him to store it in long-term memory
(LTM). If someone later asks Janet where she got the football, she will retrieve that information from her episodic LTM. Episodic memory
holds information about how things appeared and when they occurred; it stores things that depend on context. The language comprehension of the children also illustrates another type of LTM. Semantic LTM, or absolute threshold, holds all the information they need to use language; it includes not only words and the symbols for them, their meaning and what they represent, but also the rules for manipulating them. When Janet hears the words “football,” “water fountain,” and “locker,” she effortlessly retrieves their meanings from LTM. Furthermore, metamemory, an understanding of the attributes of one’s own memories, is demonstrated. Janet knows to rehearse the combination to prevent forgetting it.


Jacob probably employed mental imagery and relied on a cognitive map
to direct Janet to the equipment room. From his substantial mental representation of the school environment, Jacob retrieved a specific route, guided by a particular sequence of meaningful landmarks. In addition to their language capabilities and their abilities to form and follow routes, a number of other higher-level mental processes suggest something of the intelligence of these children. They appear to be following a plan that will result in a football game. Simple problem solving is demonstrated by Janet’s calculation of how long it will take to retrieve the football and in Jacob’s decision to use the gym floor as a substitute for the football field.




Theoretical and Methodological Approaches

To understand cognitive psychology, one must be familiar not only with the relevant questions—the topic matter of the discipline—but also with the approach taken to answer these questions. Cognitive psychologists typically employ an information-processing model to help them better understand mental events. An assumption of this model is that mental activities (the processing of information) can be broken down into a series of interrelated stages and scientifically studied. A general comparison can be made between the information processing of a human and a computer. For example, both have data input into the system, humans through their sense organs and computers through the keyboard. Both systems then translate and encode (store) the data. The computer translates the keyboard input into electromagnetic signals for storage on a disk. People often translate the raw data from their senses to a linguistic code that is retained in some unique human storage device (for example, a piercing, rising-and-falling pitch may be stored in memory as “baby’s cry”). Both humans and computers can manipulate the stored information in virtually limitless ways, and both can later retrieve information from storage for output. Although there are many dissimilarities between how computers and humans function, this comparison accurately imparts the flavor of the information-processing model.


In addition to constructing computational models that specify the stages and processes involved in human thought, cognitive psychologists use a variety of observational and experimental methods to determine how the mind works. Much can be learned, for example, from the study of patients with neuropsychological disorders such as the progressive dementias, including Alzheimer’s disease. The “lesion,” or brain injury, study is the oldest and most widely used technique to study brain function. Examining what happens when one aspect of cognition is disrupted can reveal much about the operation of the remaining mechanisms.


Behavioral studies—in contrast to “lesion” studies—examine cognitive function in healthy subjects, using a variety of experimental methods developed throughout the twentieth century. One of the continuing challenges of cognitive psychology is the construction of experiments in which observable behaviors accurately reveal mental processes. Researchers bring volunteers into the laboratory and measure, for example, the time it takes for subjects to judge whether a word they are shown had appeared in a list of words they had earlier studied.


Other researchers study human cognition in more naturalistic settings called field studies. In one such study, the average score of grocery shoppers on a paper-and-pencil arithmetic test was 59 percent, but their proficiency in the supermarket on analogous tasks reached ceiling level (98 percent). Much of what is done in the laboratory could be thought of as basic research, whereas field approaches to the study of cognition could be characterized as applied research.




Applied Research in Cognitive Psychology

For many psychologists, the desire to “know about knowing” is sufficient reason to study human cognition; however, there are more tangible benefits. Examples of these widespread practical applications may be found in the fields of artificial intelligence and law and in the everyday world of decision making.


Artificial intelligence (AI) is a branch of computer science that strives to create a computer capable of reasoning, processing language, and, in short, mimicking human intelligence. While this goal has yet to be obtained in full, research in this area has made important contributions. The search for AI has improved the understanding of human cognition; it has also produced applied benefits such as expert systems. Expert systems are computer programs that simulate human expertise in specific domains. Such programs have been painstakingly developed by computer scientists who have essentially extracted knowledge in a subject area from a human expert and built it into a computer system designed to apply that knowledge. Expert systems do not qualify as true artificial intelligence, because, while they can think, they can only do so very narrowly and on one particular topic.


A familiar expert system is the “chess computer.” A computerized chess game is driven by a program that has a vast storehouse of chess knowledge and the capability of interacting with a human player and “thinking” about each game in which it is involved. Expert systems are also employed to solve problems in law, computer programming, and various facets of industry. A medical expert system has even been developed to consult interactively with patients and to diagnose and recommend a course of treatment for infectious diseases.


There are legal implications for the cognitive research of Elizabeth F. Loftus and her colleagues at the University of Washington. Some of their experiments demonstrate the shortcomings of human long-term memory, research relevant to the interpretation of eyewitness testimony in the courtroom. In one study, Loftus and John Palmer showed their subjects films of automobile accidents and asked them to estimate the speeds of the cars involved. The critical variable was the verb used in the question to the subjects. That is, they were asked how fast the cars were going when they “smashed,” “collided,” “bumped,” “hit,” or “contacted” each other. Interestingly, the stronger the verb, the greater was the speed estimated. One interpretation of these findings is that the nature of the “leading question” biased the answers of subjects who were not really positive of the cars’ speeds. Hence, if the question employed the verb “smashed,” the subject was led to estimate that the cars were going fast. Any astute attorney would have no trouble capitalizing on this phenomenon when questioning witnesses to a crime or accident.


In a second experiment, Loftus and Palmer considered a different explanation for their findings. Again, subjects saw filmed car accidents and were questioned as to the speeds of the cars, with the key verb being varied as previously described. As before, those exposed to the verb “smashed” estimated the fastest speeds. In the second part of the experiment, conducted a week later, the subjects were asked additional questions about the accident, including, “Did you see any broken glass?” Twenty percent of the subjects reported seeing broken glass, though none was in the film. Of particular interest was that the majority of those who made this error were in the group that had been exposed to the strongest verb, “smashed.”


Loftus and Palmer reasoned that the subjects were melding actual information that they had witnessed with information from another source encountered after the fact (the verb “smashed” presented by the questioner). The result was a mental representation of an event that was partly truth and partly fiction. This interpretation also has implications for the evaluation of eyewitness testimony. Before testifying in court, a witness will likely have been questioned numerous times (and received many suggestions as to what may have taken place) and may even have “compared notes” with other witnesses. This process is likely to distort the originally experienced information.


Consider next the topic of decision making, an area of research in cognitive psychology loaded with practical implications. Everyone makes scores of decisions on a daily basis, from choosing clothing to match the weather, to selecting a college or a career objective. Psychologists Amos Tversky and Daniel Kahneman are well known for their research on decision making and, in particular, on the use of heuristics. Heuristics are shortcuts or rules of thumb that are likely, but not guaranteed, to produce a correct decision. It would seem beneficial for everyone to appreciate the limitations of such strategies. For example, the availability heuristic often leads people astray when their decisions involve the estimating of probabilities, as when faced with questions such as, Which produces more fatalities, breast cancer or diabetes? Which are more numerous in the English language, words that begin with k or words that have k as the third letter? Experimental subjects typically, and incorrectly, choose the first alternative. Kahneman and Tversky’s research indicates that people rely heavily on examples that come most easily to mind—that is, the information most available in memory. Hence, people overestimate the incidence of breast-cancer fatalities because such tragedies get more media attention relative to diabetes, a more prolific but less exotic killer. In a similar vein, words that begin with k come to mind more easily (probably because people are more likely to organize their vocabularies by the initial sounds of the words) than words with k as the third letter, although the latter in fact outnumbers the former. One’s decision making will doubtless be improved if one is aware of the potential drawbacks associated with the available heuristic and if one is able to resist the tendency to estimate probabilities based on the most easily imagined examples.




Cognitive Contexts

The workings of the human mind have been pondered throughout recorded history. The science of psychology, however, only dates back to 1879, when Wilhelm Wundt
established the first laboratory for the study of psychology in Leipzig, Germany. Although the term was not yet popular, Wundt’s primary interest was clearly in cognition. His students laboriously practiced the technique of introspection
(the careful attention to and the objective reporting of one’s own sensations, experiences, and thoughts), as Wundt hoped to identify through this method the basic elements of human thought. Wundt’s interests remained fairly popular until around 1920 when John B. Watson, a noted American psychologist and behaviorist, spearheaded a campaign to redefine the agenda of psychology. Watson was convinced that the workings of the mind could not be objectively studied through introspection and hence mandated that the proper subject matter for psychologists should be overt, observable behaviors exclusively. In this way, dissatisfaction with a method of research (introspection) led to the abandonment of an important psychological topic (mental activity).


In the 1950s, a number of forces came into play that led to the reemergence of cognitive psychology in the United States. First, during World War II, considerable research had been devoted to human-factor issues such as human skills and performance within, for example, the confines of a tank or cockpit. After the war, researchers showed continued interest in human attention, perception, decision making, and so on, and they were influenced by a branch of communication science known as information theory, which dealt abstractly with questions of information processing. The integration of these two topics resulted eventually in the modern information-processing model.


Second, explosive gains were made in the field of computer science. Of particular interest to psychology were advances in the area of artificial intelligence. It was a natural progression for psychologists to begin comparing computer and brain processes, and this analogy served to facilitate cognitive research.


Third, there was growing dissatisfaction with behavioral psychology as defined by Watson and with its seeming inability to explain complex psychological phenomena. In particular, Noam Chomsky, a well-known linguist, proposed that the structure of language was too complicated to be acquired via the principles of behaviorism. It became apparent to many psychologists that to understand truly the diversity of human behavior, internal mental processes would have to be accepted and scientifically studied.


Working memory, or short-term memory, emerged as an important theoretical construct in the 1980s and 1990s. Everyday cognitive tasks—such as reading a newspaper article or calculating the appropriate amount to tip in a restaurant—often involve multiple steps with intermediate results that need to be kept in mind temporarily to successfully accomplish the task at hand. Working memory refers to the system or mechanism underlying the maintenance of task-relevant information during the performance of a cognitive task. As the “hub of cognition,” working memory has been called “perhaps the most significant achievement of human mental evolution.” According to Alan Baddeley, working memory comprises a visuospatial sketchpad; a phonological loop, concerned with acoustic and verbal information; a central executive that is involved in the control and regulation of the system; and an episodic buffer that combines information from long-term memory with that from the visuospatial sketchpad and the phonological loop. Prospective memory has also emerged as an important domain of research in cognitive psychology. This type of memory involves the intention to carry out an action in the future: for instance, to pick up dry cleaning after work.


Cognitive psychology is now a vibrant subdiscipline that has attracted some of the finest scientific minds. It is a standard component in most undergraduate and graduate psychology programs. More than half a dozen academic journals are devoted to its research, and it continues to pursue answers to questions that are important to psychology and other disciplines as well. The cognitive perspective has heavily influenced other subfields of psychology. For example, many social psychologists are interested in social cognition, the reasoning underlying such phenomena as prejudice, altruism, and persuasion. Some clinical psychologists are interested in understanding the abnormal thought processes underlying problems such as depression and anorexia nervosa; a subspecialty—cognitive behavioral therapy—treats mental illness using methods that attempt to directly treat these abnormal thoughts.


The burgeoning field of cognitive science represents a contemporary union of cognitive psychology, neuroscience, computer science, linguistics, and philosophy. Cognitive scientists are concerned with mental processes but are particularly interested in establishing general, fundamental principles of information processing as they may be applied by humans or machines. Their research is often heavily dependent on complex computer models rather than experimentation with humans. With fast-paced advances in computer technology, and the exciting potential of expertise shared in an interdisciplinary fashion, the field of cognitive science holds considerable promise for answering questions about human cognition.




Bibliography


Ashcraft, Mark H. Human Memory and Cognition. 4th ed. Upper Saddle River, N.J.: Pearson Prentice Hall, 2006. Print.



Baddeley, Alan D. “The Cognitive Psychology of Everyday Life.” British Journal of Psychology 72, no. 2 (1981): 257-269. Print.



Berger, Dale E., Kathy Pezdek, and William P. Banks, eds. Applications of Cognitive Psychology. Hillsdale, N.J.: Lawrence Erlbaum, 1987. Print.



Cialdini, Robert B. Influence: Science and Practice. 5th ed. Boston: Pearson Education, 2009. Print.



Hughes, Brian M. Conceptual and Historical Issues in Psychology. New York: Pearson, 2012. Print.



Kahneman, Daniel, Paul Slovic, and Amos Tversky, eds. Judgment Under Uncertainty: Heuristics and Biases. New York: Cambridge University Press, 2007. Print.



Kendler, Howard H. Historical Foundations of Modern Psychology. Chicago: Dorsey Press, 1987. Print.



Manktelow, K. I. Thinking and Reasoning: An Introduction to the Psychology of Reason, Judgement, and Decision Making. New York: Psychology P, 2012. Print.



Miyake, Akira, and Priti Shah, eds. Models of Working Memory: Mechanisms of Active Maintenance and Executive Control. New York: Cambridge University Press, 1999. Print.



Pinker, Steven. How the Mind Works. London: Penguin, 2005. Print.



Siegal, Michael, and Luca Surian. Access to Language and Cognitive Development. New York: Oxford UP, 2012. Print.



Sternberg, Robert J., and Talia Ben-Zeev. Complex Cognition: The Psychology of Human Thought. New York: Oxford University Press, 2001. Print.



Wells, Gary L., and Elizabeth F. Loftus, eds. Eyewitness Testimony: Psychological Perspectives. New York: Cambridge University Press, 1987. Print.

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