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Chapter 1. Part One : What is Psychology? Russell A. Dewey. What is Psychology?. Answer: “Psychology is the science of behavior and mental processes.”
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Chapter 1 Part One: What is Psychology? Russell A. Dewey
What is Psychology? • Answer: “Psychology is the science of behavior and mental processes.” • Most people associate psych with therapies designed to help people w/emotional and mental problems and think psychologists are all therapists. • Reality: “In actuality, many psychologists are not therapists. Some are researchers in laboratories, some are full-time teachers and researchers. Some are consultants to business and industry. Many never do therapy in their lives.”
Specialties • Clinical Psychology (therapists working with mentally ill patients) • Counseling Psychology (work with students in schools, workers in the workplace) • Social Psychology (study the psychology of social relations) • Industrial/Organization (study psychological features of large organizations) • Cognitive Psychology (studies like the ones Nisbett pursues) • Development Psychology(studies childhood and adolescent development, both cognitive and emotional) • Physiological Psychology(psychological contributions of physiology) • Comparative and Animal Psychology(self-explanatory) • Health Psychology(self-explanatory) • Behavioral Medicine (Studies relationship between behavior and health)
Four Approaches to Psychological Research • Biological explanations are based on knowledge of living cells and organic systems, how brain structure affects behavior, mental life, etc. • Behavioral research emphasizes actions (behaviors). Behaviorists typically relate actions to the organism's environment and history of learning. Field research on animals is an example of behavioral research. So is intensive behavior therapy with autistic children, one of the most effective treatments for autism. • Cognitive approaches stress information processing. Cognitive psychologists study the interactions of thoughts, images, knowledge, and emotions.
Subjective approaches describe unique thoughts, feelings, and experiences of individuals. This includes introspectionist approaches like Wundt’s and those followed in what is called phenomenology. All four perspectives are relevant to almost all areas of psychology. Anxiety, for example, can be studied as a biological response, a set of behaviors, a thought process, or an experience. Psychology is by nature an integrative science, employing a variety of perspectives on the same events.
The 1800s • Phrenology: Francis Gall 1796. Studied bumps on the skull as indicators of brain growth. More bumps, more brain development. Skull was mapped out showing which brain functions/mental functions were covered by bumps (or lack thereof) in that area. These maps bear no relation to underlying brain areas and their cognitive/mental functions. • What Phrenology got right: 1) diff brain areas cover different mental functions; 2) sought a scientific/objective way to measure psychological qualities (as does modern psychology); 3) testing individuals can reveal valuable info about individuals in a short time (still a goal and practice of modern psych); 4) neurons do grow more in response to more brain activity, although this does not affect the size of the brain nor the shape of the skull.
Psycho-Physics: studies the interaction of the mind (psyche) and the physical world (physics). Psychophysicists were interested in exploring how energy from the physical world such as light and sound gave rise to mental experience such as perception of brightness and loudness. Wundt’s “New Psychology”: First to call himself a “psychologist”. Thought “only immediate experience” yields “certain reality”. To be a science, psychology would have to deal directly with the “data of experience”. This was to apply the typical approach to other sciences (botany, zoology) to psychology: science begins with observation. You then try to work out an agreement about what is observed by comparing data from different observers. For Wundt, the “data of experience” was what is evident through introspection.
The problem with introspection: different minds introspect different things, even when stimulated by the same external conditions. Wundt had trouble accepting this, but it was proved over and over to be the case. William James and Functionalism: James thought the mind is a process, a function of the organism. Given that by this point (late 19th century) James assumes that the organism is a product of evolution, if we developed higher cognitive functions than our ape ancestors, these higher functions must be useful to our survival. So to understand our minds and hence our psychological qualities, we needed only ask “What is this or that capacity of mind used for?”
Watson and Behaviorism: After attempting to study psychological phenomena by way of introspection and functionalist approaches that looked to reveal features of the states of consciousness (even when studying Animals!!!), Watson got frustrated and asked “Why not just describe the behavior and leave it at that?” He thought psychology could succeed without even mentioning consciousness or the content of consciousness revealed through introspection. One great advantage of behaviorist psychology: it could be applied to creatures (animals) that have no language with which to express their inner thoughts! Watson did not invent behaviorism, but with his position as editor of Psychological Review at Johns Hopkins, he gave it a name and publicized it.
Mid-20th Century BehaviorismClassical Conditioning + Operant Conditioning • Watson thought all behavior could be generated by classical conditioning such as the kind of behavior that could be elicited from a dog using Pavlov’s laws of learning, plus some additional principles like trial and error learning. Problem: Never produced effective behavioral results, despite early promise. • B.F. Skinner in 1950 offered a newer, more powerful set of learning tools called “operant conditioning” that he claimed could fulfill the promise that classical conditioning and trial and error laws of learning failed to. Operant conditioning applies the principles of reinforcement and punishment and Skinner hyped the new approach in his book Walden Two where he claimed that he could make anyone behave in specific ways using his techniques.
In fact: operant conditioning failed to produce the results it promised. It is still used to train animals and non-verbal humans (if you take your dog or cat to be trained, these techniques will be used with great success). However, it did not manage to explain the much more complex kinds of human behavior. JP: Chomsky vs. Skinner and the acquisition of language (famous 1957 paper by Noam Chomsky challenges Skinner’s account of language acquisition based on operant conditioning techniques). Led to the development of Generative Grammar (the basis for the Theory of Universal Grammar propounded by Chomsky most of his life as a linguist)
Modern Trends • Cognition and Neuroscience • Cognition: in mid-20th century psychologists began to notice what they thought was a connection between information-processing routines of newly-available, powerful modern computers (like the IBM 360) and what seemed like analogous processing in humans. • George Miller’s studies in memory revealed that human beings encode information received through the senses before they store it. This was unexpected, but it opened up the possibility that memory in a computer and in a human being are very similar, pushing the analogy between computer processing and human mental processing even further along.
By the 1970s, psychology was caught in a ‘cognitive revolution’. The emphasis on cognition was “disciplined, objective, and relied on experimentation.” As Dewey puts it, “While memory researchers focused on manipulating encodings and documenting changes in memory retrieval, others outside psychology in the fields of computer science and artificial intelligence studied problem solving, visual scene analysis, and other information processing skills.” Behaviorism did not disappear in the cloud of enthusiasm for the new emphasis on cognition, mental processing, and ways to test theories of how human minds encode memories, process information, solve problems through special cognitive processes, etc. While cognitive techniques took over experimental psych, behavioral techniques still dominate animal research.
Neuroscience As machines capable of scanning the brain of a living person became available (e.g., MRIs and fMRIs) in the 1970s and 1980s, psychologists began to conduct investigations into what behaviors and mental states corresponded to measurable activity in various parts of the brain. Almost everything we presently know about which parts of the brain are responsible for which particular mental functions has come from these studies, when combined with what brain physiologists have discovered in the last 50 years about how the brain works at the cellular, structural level.
Principles of Critical Thinking • Avoid jumping to conclusions [Suspend judgment; keep an open mind until you have adequate evidence; tolerate uncertainty; avoid oversimplification.] • Examine assumptions [Identify premises or starting assumptions; avoid accepting an idea simply because it appeals to pre-existing biases or assumptions.] • Generate new ideas [Experiment with ideas opposite to those normally considered; ask questions; consider other perspectives.] • Evaluate evidence [Ask whether an idea generates surprising predictions. Look for actual tests of an idea. See what experts in the field have to say about controversial ideas.]
The Role of Science • Putting ideas to a test. • Karl Popper: Science is “conjection [speculation] and refutation.” • George Polya: “What is the scientific method except Guess and Test?” • What is the key to making a hypothesis testable? • 1) For Popper, it must be possible for the results to falsify the hypothesis. This means choosing a hypothesis which predicts a certain outcome such that if it doesn’t occur, the hypothesis has failed. • Example of an unfalsifiable hypothesis: Freud’s explanations for adult behavior based on unconscious motives drawn from childhood traumas: any adult behavior could always be explained according to the theory, and it made no predictions that would prove the theory correct.
Model Building or “Mapping” Reality • Metaphors that describe activities of scientists: • The puzzle: scientists are largely motivated by puzzle solving. They want to explain things that are strange or unexplained. They gain satisfaction from achieving new insights into how things work. • The filter: scientists start with lots of different ideas, particularly in frontier areas with problems to be solved. Many ideas are eventually disproved. Scientists try to filter out misleading and false claims. • The map: scientific theories are like maps. They preserve information about selected portions of reality. Like maps, they are schematic (incomplete or skeletal) but extremely useful in particular situations.
Science is self-correcting. It modifies its theories in the face of new evidence (Aristotle->Newton; Newton->Einstein; Ptolemy->Copernicus) • Science is not dedicated to any particular point of view, although particular scientists may be. Science as a institution aims at accuracy, not dogma. • Key Tools of Science • Operational Definitions: These are necessary because you must relate the words (and associated ideas to which they refer) in a theory/hypothesis to “concrete, measurable events in the world.” • Variables and Values • A variable is some observable characteristic in the world that can change. A value is the number or score used to express the particular state of a variable at a given time. For example, temperature is a variable in my present environment, and the current value of that variable is 90 degrees Fahrenheit.
Reliability and Validity • A test is reliable if it produces the same results over and over when measuring the same thing. • A test is valid if it measures what you think it measures, as determined by some independent way of measuring the same thing. • Self-Report Measures: Notoriously Unreliable • This is particularly important when a psychologist relies on polling to establish what is true about any psychological phenomenon. It is often a measure used when studying health-related behaviors (a study of obesity and food intake sometimes is based on what the participants in the study report about their food intake…..these reports are notoriously inaccurate).
Constructs and the Problem of Reification • Many of the psychological states and phenomena that psychologists seek to understand and explain are things that cannot be strictly observed. For example: intelligence, happiness, personality. These are called constructs. They are really ideas that represent things we cannot observe directly, but which we think play a causal role in the psychological phenomena we want to understand. In physics there are also constructs. In Newtonian Mechanics, the “f” in “f=ma” represents force. There is no way to actually observe a force. So we have to replace something observable for what counts in the theory as “f” when testing the theory. • When a construct is treated like a real thing in the world, but there is nothing in the world that corresponds to it, this is called reification of that construct/idea. • Whether a particular construct has been reified or not is hard to determine. In the end, what matters is whether you can find observable evidence for it.
Part Four: Observational and Experimental Research
Observational Research • A non-experimental research method. • Seven Types: Naturalistic, Controlled, Standardized Testing, Clinical, Surveys and Polling, Interviews, Microanalysis • Naturalistic:researcher attempts to observe without being directly involved in the phenomenon. It is ‘natural’ because the subjects of observation are allowed to ‘behave naturally’. (uses video cameras, one-way mirrors, etc.) • Controlled: researchers control the conditions of the phenomena being observed so the ‘subjects’ experience the same conditions. Used to detect individual differences in response of subjects. Allows for grouping subjects into different types according to their particular reaction styles (e.g.,: stranger approaches with newborns) • Standardized Testing: This is a form of controlled observation. SAT, GRE, “Bayley Box” (A standardized test for infants performed using a box of objects and toys. The examiner uses these objects to determine the child's skills.), etc.
Observational Research cont’d • Clinical: Here the researcher is a skilled clinician who interacts with the subject and records what transpires. Some think the contribution of this kind of research is unreliable because different clinicians come up with different results. Proponents think discoveries can be made when a clinician interacts and responds to what a subject says or does and bases further interaction on what has already transpired. (e.g., Piaget’s studies of children to see how they view the world). • Surveys and Polling: This is a controlled kind of research that captures data from a very large population of subjects, which is its main virtue. The main goal of this kind of research is to discover the characteristics of a large population on the basis of a small, but (ideally) representative sample.
Observational Research cont’d • Interviews: This combines the structured/controlled approach to data collection associated with surveys, polls, and standardized testing, but in one-on-one interviews where greater depth and detail of questions and answers can be achieved. All interviewees are asked the same questions. (example: 12-hour interviews of Spanish-speaking families trying to learn how they made the transition from rural to urban living in Colorado). • Microanalysis: detailed analysis of brief events (e.g., “mother/baby dance”).
Correlation and Prediction • The data of observational research is called correlation data because what the researcher is looking for are patterns in the phenomena observed, and these patterns must necessarily be co-relational (things occurring together), at least at first. • What is good about seeking out correlations: you can discover that the values of one variable can be used to predict the values of another (people whose parents committed suicide are N times more likely to commit suicide themselves, for example). • JP: Multiple regression analysis is a statistical method for trying to detect correlations between independent and dependent variables in an observational study.
Correlation and Prediction cont’d • Correlations come in degrees: cf. drinking and school performance. When a correlation is strong, you can predict the dependent variable (performance in school) by knowing the value of the independent variable (drinks per week). • Negative correlation: The value of one variable goes up as the other goes down, or vice versa (again, drinking goes up, school performance goes down).
Why it is Hard to Show Correlation is Causation • Consider the correlation between heavy drinking and poor school performance mentioned earlier. This could be explained in any of the following ways, each of which suggests a cause that is not yet in evidence in the correlation study: • Perhaps (1) alcohol makes people stupid, or (2) higher-achieving students are more likely to lie and say they do not drink even if they do, or (3) the students who tend to drink tend to be poorer students to begin with, or (4) people who are hung-over from a drinking binge tend to skip class, or (5) students in academic trouble drink in order to drown their sorrows after receiving bad grades.
Predictions Based on the Actuarial Method • Actuarial Method = correlations drawn from very large bodies of data [aka “data mining”] (Paul Meehl first championed this method). • Meehl showed that correlations derived from “data mining” could out-predict trained experts (e.g., therapists trying to estimate the likelihood of patient relapse). • Cautionary Note: Not all phenomena lend themselves to prediction. Systems that have a high degree of built-in chaos (e.g., weather) are not good candidates for this approach to prediction. • Cohen’s Folly: tried to use her expertise to figure out which of 60 variables would predict likely dropouts in a small drug treatment program. Finally gave up and just fed the considerable 60-variable dataset containing values into a multiple regression analysis routine and out popped numerous factors that proved predictive of failure in any given individual.
Questionnaires, Surveys and Polls • All are types of Survey Research. • First, some definitions: • Target population: the population you mean to learn about. • Sample: the specific group of individuals you actually survey/poll/question. • Random Sample: A method for selecting members of a large population that will prove representative of the target population, while only being a sample of that population. Randomizing, properly done, is known on the basis of the laws of probability to minimize the chance the sample population is unrepresentative of the target population.
Questionnaires, Surveys and Polls cont’d • Large N’s = More-Successful Surveys/Polls/Questionnaires • Why? Because of the “Law of Large Numbers”. The larger the number of people in the sample group, the more likely the average of that group on all measures will closely resemble the average on all measures of the target population.
Questionnaires, Surveys and Polls cont’d • Biased Samples in Questionnaire Research • “Bias” is NOT the same as “Based on an Intention to CHEAT” • A good, unbiased sample: Use a random number generator to select 50 names of people who will receive questionnaires from a complete list of people including the names of all the members of the target population. • A bad, biased sample: Go where you hear many of the members of the target population pass by and pick out 50 at random. (JP: Why? Answer: It will be a “convenience sample” and these are known to be unrepresentative. Classic example: Internet polls that rely on self-selection for the sample population)
Questionnaires, Surveys and Polls cont’d • Sampling Error: This is a known value based on the size of the sample population as a percentage of the target population. Laws of probability allow us to say with some degree of certainty how likely it is that, on a given sample population size, that population is representative. Also called margin of error. Often expressed this way: “The poll states that 43% of voters polled will vote for Jimmy John, with a margin of error of 3%”. This means that given the sample size, the actual number of voters likely to vote for Jimmy John could be as low as 40% and as high as 46%.
Experimental Research and its Pitfalls • Definitions: • Experimental Research = Research in which there is a Manipulation. • Manipulation = The Experimenter introduces a change into the system. • Experiment = Change something in a controlled system and see what happens. • Value: useful because properly designed experiments allow for the discovery of cause-effect relationships in a phenomenon. • Independent Variable = the suspected cause of the phenomenon. This is the variable the experimenter manipulates. • Dependent Variable = all other variables detectable in the phenomenon (at least some or one of which is the hoped-for effect of the dependent variables causal power).
Experimental Research and its Pitfalls cont’d • Subject Variables = variables that are neither manipulated by the experimenter nor measured to detect any changes resulting from changes in the independent variable. (e.g., the religious affiliation, sex, weight, height of subjects, depending on the point of the study). • Two-Group Studies = where two groups are compared, with the control group getting no experimental intervention/treatment, and the experimental group getting the intervention/treatment. Also called between-subjects design, the purpose is to discern whether the experimental intervention applied to the experimental group produces any detectible change in the members of that group, as compared with those not received the intervention. • Within-Subjects Design = a study that watches changes in the subjects of the study over time under changing conditions (with/without exercise, for example).
Experimental Research and its Pitfalls cont’d • The Problem of Confounding Variables = in a between-subjects design, the hope is that the only difference between the control and the experimental groups is the intervention applied to the latter. But this is seldom achieved, and the variables that differ between the two groups that are not associated directly with the intervening variable are called confounding variables (because they confound/interfere with the attempt to isolate the effective causes of the results in the experimental group).
Experimental Controls • Experimental control = in one sense, it is to remove a confounding variable by controlling it. But experimental control is just a kind of methodological control in which a variable is controlled in an experiment so it cannot interfere with the results. • Placebo Effect = any situation in which a person’s belief in a treatment contributes to the effect of the treatment. Placebo effects are not imaginary, it is just that the cause of the effect seems to lie in something produced by the fact that the person believes the effect will result. • Use of Placebo in Psychological Experiments = In Two-Group studies, giving the Control Group a placebo guarantees that the study can separate whatever was the effect of the intervention applied to the Experimental Group from the expected Placebo Effect, which should apply to both groups.
Experimental Controls cont’d • How do you control the Placebo Effect? Answer: you give the Control Group a placebo (or alternatively, you create a placebo effect in the control group, which comes to the same thing). • Single-Blind Experiments = Two-Group studies where neither group knows which has received the ‘active intervention’ and which the placebo, but the experimenter does know. • Double-Blind Experiments = Two-Group studies where neither the control group, experimental group, nor the experimenter know which group got the intervention, which the placebo. (e.g., the subliminal tapes study) • Why do a Double-Blind Experiment? (Answer: experimenters can affect the outcome of the study by unconscious behaviors that affect the two groups differently)
Two Powers of Science • Prediction and Control • Some dislike the idea of “controlling” the phenomena studied by a science (this is viewed as treating nature as hostile and unruly, and makes science seem a bit macho). This led to Dewey to revise his twin powers of science as follows to focus on Understanding rather than Control:Prediction and Understanding: Prediction Science can give us advance warning of phenomena. Through observational research, we can detect correlations and make predictions. • Understanding Science can help us gain knowledge about systems so we understand how they operate. Having analyzed components of a system and how they work together, we can interact more skillfully with the system. We can nurture it or repair it, such as ecologists who repair a damaged ecosystem, or mechanics who fix a car.
Chapter 2:The Human Nervous System Part One: The Brain Russell A. Dewey
The Brain • Most complex piece of matter in the universe. Surface is convoluted which increases the surface area of the cortex. • Consists of: neurons, surrounded by glial cells. • Human Nervous System = Two parts, Central Nervous System (CNS) and Peripheral Nervous System (PNS) • CNS has three parts: forebrain, midbrain, and hindbrain. • Convolutions lead to: fissures (deep folds) caused by the more rapid growth of the different layers of brain cells, and lobes (regions of the cortex created by the deeper fissures as development proceeds). Opposite of a fissure = gyrus (top of a folded area of the cortex, like a hilltop). • Top of brain = Cerebrum (includes outermost layer, i.e., Cerebral Cortex [3.2 mm thick])
Stages of Brain Development Displaying all three structures at each stage.
The Brain cont’d • Cortex = any outer layer of any brain structure. There is a cortex for the thalamus and cerebellum, not just the cerebrum. • Gray Matter = the cortical layer of any part of the brain, gray because it contains densely packed cell bodies. • White Matter = the cells in the noncortical areas of the brain. These contain axons which are communication links between cortical layers and other parts of the brain, white because covered with myelin sheath, which is a fatty substance. • Brain plasticity (adaptability): one sign of this is that people can develop normal mental functions even with severely reduced brains (hydrocephalics, babies with ½ of the cerebral cortex missing, etc.)
The Brain cont’d • Lobes of the Brain: Occipital (back) deals with vision, location of primary visual cortex; Parietal (middle) in right hemisphere deals with spatial processing; Temporal (side below the Sylvia fissure), handles secondary visual processing + some hearing + some complex information processing [stimulation of upper region can produce déjà vu, and other areas can produce religious ecstatic states]; Frontal (front) is largest of any animal; Prefrontal handle executive functions; Frontal lobe seems to be involved in planning, creative activities. • Fissure of Rolando: separates the sensory cortex which lies behind the fissure and the motor cortex which lies in front of it (disputed by modern neuroscientists who say sensory and motor functions lie front and back equally).
