1. The discipline of psychology:

A. was strongly influenced by philosophy.*

B. arose independently of other disciplines.

C. is unrelated to newer fields like computer science.

D. is constantly at odds with biology and medicine.

80% correct, item-to-total r_pb = .30. Psychology came out of philosophy, in particular the philosophy of mind that essentially began with Descartes (though even the ancient philosophers were interested in questions about knowledge as well as various metaphysical and ethical problems). In fact, I believe that the University of Arizona was the last school in the United States to break psychology away from philosophy, and that wasn't until the 1950s (though in most universities, the split occurred much earlier than this). The split with philosophy really began in the 19th century, as a "physiological psychology" began to develop out of increased knowledge of the anatomical and physiological basis of sensation and perception. So, psychology also had close ties to physiology and medicine, and in fact in the 19th century William James (who himself was a physician) classified psychology as a biological science (there really weren't social sciences then, as we know them now). Now, of course, psychology and philosophy have come back together in the interdisciplinary field known as cognitive science -- again, attacking problems of knowledge with the tools of their respective fields, but each learning from the other in ways that haven't happened until relatively recently.

2. Psychology is a cognitive science because:

A. emotion and motivation are irrelevant to behavior.

B. it assumes that knowledge guides behavior.*

C. the brain is the physical basis of the mind.

D. psychological principles cannot be reduced to physical laws.

64%, .23. All the cognitive sciences are concerned with how knowledge is acquired, stored, and psychology, at least, is also interested in how knowledge is used to guide behavior. That's what the doctrine of mentalism is all about: mental states are of interest to psychologists because we explain behavior in terms of them. It's true that the brain is the physical basis of mind, but for a long time neither psychology nor cognitive science was particularly interested in the brain, and there are some cognitive scientists who are more interested in computers than in brains. Some psychologists are reductionists, believing that the only genuine scientific explanations are at the level of physical structures, but most psychologists believe that the psychological level of explanation -- which explains behavior in terms of mental states, and explains cognition, emotion, and motivation in terms of psychological principles -- is valid in and of itself. Otherwise, they wouldn't be psychologists.

3. The word reflex has its origin in:

A. Descartes' idea that animals, but not humans, act automatically.

B. Descartes' desire to explain such acts as sneezing without reference to the soul.

C. Descartes' belief that the energy from the outside is reflected back by the nervous system to the animal's muscles.*

D. none of the above

69%. .27. Psychology has a history, and part of that history has to do with the discovery and naming of the reflex -- by Descartes, based on his belief that the energy of the stimulus was reflected back into the environment by behavior. Descartes is important for psychology, because he attempted to separate human behavior from the behavior of "lower" animals. Descartes understood the humans had automatic reflexes, such as sneezing, that were part of our "animal nature"; but he asserted that we also had minds, by which we could become consciously aware of things, and consciously control them as well. This notion of the reflex as automatic, and as a piece of behavior that we shared with "lower" animals, laid the foundation for the work of Pavlov, Thorndike, and others on "conditioned reflexes", which they also thought of as automatic and unconscious. And when behaviorists such as Watson rejected the mind and consciousness as somehow unscientific, all they were left with were reflexes. In fact, the very notion of the reflex as reflection of environmental events can be found at the root of the S-R theory of learning, which holds that learning can be understood in terms of events that are external to the organism.

4. A rat can walk, chew, swallow, and track moving objects with its eyes, but it cannot find food or water for itself. These observations most suggest that:

A. the limbic system and lower regions are intact, but the cerebral cortex is damaged.

B. the midbrain and lower regions are intact, but the forebrain is damaged.*

C. the medulla and cerebellum are intact, but the midbrain is damaged.

D. the spinal cord is intact, but the medulla and cerebellum are damaged.

52%, .30.Reflexive behaviors related to vegetative functions are generally mediated by "lower" brain centers associated with the hindbrain and the midbrain. "Voluntary", nonreflexive behaviors are generally mediated by "higher" brain centers associated with the forebrain -- but not necessarily the cerebral cortex. Damage to the hypothalamus, a subcortical structure, can impair drinking and feeding behaviors, for example -- even though the animal may reflexively swallow of food or water is placed in its mouth.

5. A general characteristic of the primary sensory areas is that:

A. the amount of tissue devoted to a specific area is related to that area's function.*

B. the somatosensory area contains the primary motor area that corresponds to the same part of the body.

C. they are localized in only two lobes of the cerebral hemispheres.

D. the location of a neuron in the primary sensory area depends on the importance of the body area to which that neuron corresponds.

82%, .34. The primary sensory areas are associated with different portions of the brain (the somatosensory area of the parietal lobe, the primary auditory and visual areas of the temporal and occipital lobes, respectively) than the primary motor area (in the frontal lobe). But all the cortical projection areas illustrate the organizational principles of regular association and proportional association. For example, in the somatosensory homunculus, the part of the parietal lobe that receives sensory information from the fingers is located near the parts that correspond to the hands and arms. And, again in the somatosensory homunculus, more tissue is devoted to the hands (which require lots of sensory acuity) than the arms (which do not, even though they're bigger body parts).

6. A woman with a severed corpus callosum looks at the words "Dixie Cup" flashed on a screen in a position where her eyes are fixated on the space between the two words. Which of the following is she most likely to touch with her left hand to indicate what she saw?

A. a Confederate flag*

B. a coffee cup

C. a cold drink paper cup of the "Dixie Cup" brand

D. a tennis trophy

59%, .28. Remember that information in the left visual half-field of each eye projects to the right cerebral cortex, and vice-versa; and that the right cerebral cortex controls activities performed by the left side of the body, and vice-versa. So, the word Dixie, which refers to the American South, and the rally song for the (Southern) Confederacy in the Civil War, appearing in the left visual field will project to the right hemishpere, which will make the connection to American history, and tell the left hand to point to the "Stars and Bars" of the old Confederacy. Even if you didn't know anything about American history, you could eliminate options B and C, because the right hemisphere of a split-brain patient will never process the word "cup". That leaves you with the choice of A or C. It is possible that the right hemisphere would make the connection to the Dixie cup, especially provided that the words Dixie Cup are printed right on the side of the object. But the question didn't say that they were, and in any event a much more likely association is to the Confederate flag.

7. The sending end of a neuron is the:

A. synapse.

B. axon.*

C. dendrite.

D. myelin.

49%, .15. A BAD ITEM. The provisional scoring key was incorrect, due to a typographical error (sorry). The intended correct answer was B, not A. In neuronal structure, neurotransmitters picked up at the synapse by the dendrites of the post-synaptic neuron cause an electrical discharge in the cell body which travels down the axon (which may be covered by a myelin sheath) to the terminal fibers, which release neurotransmitter into the next synapse. In this sense, the dendrites are the "receiving end" and the axon is the "sending end" of the neuron. But a better answer would have been the terminal fibers. We could have simply rescored this item changing the correct answer from A to B, but the fact of the matter is that this change wouldn't have improved the psychometric characteristics of the item sufficiently.

8. Transmission of information across the synaptic gap occurs by means of:

A. electrical charges.

B. movement of synaptic vesicles.

C. fine neurotubules.

D. chemical diffusion.*

36%, .29. There's no spark across the synapse, when the electrical impulse reaches the terminal fibers of the presynaptic neuron. Instead, there's a release (diffusion) of chemical neurotransmitter into the synapse, which in sufficient quantities can trigger an electrical discharge in the postsynaptic neuron. So, yes, there's an electrical charge, but not a spark; the charge itself doesn't go from neuron to neuron, but each neuron has its own electrical charge. And it's the synaptic vesicles that release neurotransmitter into the synapse, but they don't move -- in particular, they don't move to touch the postsynaptic neuron. The synaptic cleft remains, but filled by neurotransmitter. Neurotubules are structures in the axon and terminal fibers that mediate the transmission of an electrical impulse through a neuron.

9. Which of the following statements best describes the current status of research concerning treatment of spinal cord injuries and degenerative brain disorders in humans?

A. Neuronal transplantation and the design of growth-promoting chemicals provide hope that effective treatments will be developed in the future.*

B. The outlook for obtaining regeneration of function in these cases is dismal, with little or no evidence that effective treatments will be developed in the future.

C. Transplantation of adult neuronal tissue into the sites of brain or spinal cord damage in young children has been moderately successful in the treatment of these afflictions.

D. The use of growth-promoting chemicals to treat brain and spinal cord damage has been shown to be effective in children, but not in adults.

77%, .35. The classical view is that organisms are born with all their central nervous system neurons, and that central nervous system neurons, once destroyed, don't regenerate. We now know that this isn't exactly true. Neurons don't regenerate, exactly, but it does appear that new neurons can grow after birth -- a process called neurogenesis. It is possible that, either through neural transplantation or the promotion of "indigenous" growth of new neurons, that people with spinal-cord injuries and other injuries to the nervous system will be able to recover the lost functions. However, there is little human work in this area as yet. Almost all of the research on neurogenesis and neural transplantation has been on animal models, like mice, rather than human children or adults.

10. In Selye's concept of the generalized adaptation syndrome, the gross emotional reaction is analogous to the activation of the:

A. skeletal nervous system.

B. sympathetic nervous system.*

C. parasympathetic nervous system.

D. efferent nervous system.

75%, .27. The generalized adaptation syndrome consists of three phases: a gross emotional reaction mediated by the sympathetic branch of the autonomic nervous system; a reduction in emotionality mediated by the parasympathetic branch of the autonomic nervous system, and then exhaustion and depth as the organism's bodily resources are depleted. None of these phases involves the skeletal nervous system (which is composed of both afferent and efferent nerves).

11. In cases of paraplegia, spinal reflexes are:

A. abolished.

B. exaggerated.*

C. confined to voluntary responses.

D. conscious.

65%, .48. Paraplegics still show spinal reflexes. They just don't show conscious sensation, or voluntary motor activity, in regions of the body enervated by spinal nerves which join the spinal cord below the site of the break. However, these preserved reflexes are typically stronger than those observed in neurologically intact subjects. Apparently, in addition to mediating conscious awareness and voluntary control, the cerebral cortex sends inhibitory signals down the spinal cord which modulate, and dampen, reflex activity mediated at the level of the spinal cord.

12. Studies of brain-damaged patients indicate that the hippocampus is important for _____ functioning.

A. auditory.

B. emotional

C. memory*

D. somatosensory

94%, .28. Remember Patient H.M., who suffered damage to his hippocampus and related structures in the medial temporal lobe of the brain, and who could no longer remember things that happened to him since his operation? And Patient S.M., who suffered damage to the amygdala, and could no longer generate normal emotional responses? The hippocampus is not involved in auditory or somatosensory processing, which are mediated by portions of the temporal and parietal lobes, respectively.

13. Brain damage confined to the area of the frontal lobe, bordering on the temporal lobe near the primary motor cortex, most likely impair:

A. the ability to write.

B. the ability to read.

C. the ability to speak fluently.*

D. the ability to comprehend speech.

67%, .36. This is pretty much the location of Broca's area, which is known to be associated with Wernicke's aphasia, or expressive aphasia, in which the person has difficulty speaking fluently but who retains the capacity to understand the speech of others. Because Broca's area is close to the frontal centers involved with the muscles of the mouth, lips, and throat, speech functions are particularly impaired in Broca's aphasia. But according to the motor homunculus, the frontal areas involved in the movement of the hands are located a little further away, and so writing may not be impaired (at least not as much) -- depending, of course, on the extent of the brain damage. Broca's area does not seem to be involved in reading, as opposed to speaking. The pathways for reading involve the occipital lobe and Wernicke's area, as the pathways for speech comprehension involve the temporal lobe and Wernicke's area.

14. In negative feedback systems:

A. the feedback stops, or even reverses, the response that produces it.*

B. the feedback strengthens the response that produces it.

C. the feedback may either stop or strengthen the response that produces it, depending upon the level of the setpoint.

D. The feedback causes the response that produces it to continue at the same level.

88%, .23. A positive feedback system increases the behavior that activates it. A good example is the feedback loop that is produced when a microphone is held too close to a loudspeaker. A negative feedback system decreases the behavior that activates it. A good example is homeostatic regulation, which terminates eating (for example) when blood sugar levels are restored to appropriate levels.

15. According to the setpoint hypothesis, when the amount of body fat is significantly above the setpoint:

A. appetite increases.

B. appetite diminishes.*

C. the number of body fat cells decreases.

D. the number of body fat cells increases.

58%, .40. The setpoint hypothesis is a variant on the dual-center theory of feeding which states that each organism seeks to maintain body fat (a correlate of body weight) at a particular level, which differs from one individual to another. So, if body fat is above the setpoint, appetite diminishes, and so does eating, until body fat drops below the setpoint, at which point appetite increases, and eating begins. According to the hypothesis, everyone has a different setpoint Obesity, and the effects of various diet and exercise regimens on body weight, may depend the number and size of the individual's fat cells.

16. The parasympathetic nervous system handles

A. fight or fight behaviors.

B. tend and befriend behaviors.

C. vegetative functions.*

D. a and b

79%, .37. Remember that the very first scoring key I posted, immediately after the exam, was incorrect due to a typo (sorry again). The sympathetic nervous system handles emergency reactions to stress, including fight or flight (typically in males) or tend and befriend (typically in females). The parasympathetic nervous system handles vegetative functions. True, sympathetic activation affects vegetative functions as well, but only in times of stress. The parasympathetic nervous system handles vegetative functions, including homeostatic regulation, even in the absence of stress.

17. The deeper stages of sleep are characterized by brain waves:

A. of high voltage and low frequency.*

B. of high voltage and high frequency.

C. of low voltage and low frequency.

D. of low voltage and high frequency.

23%, .09. A BAD ITEM. The waking EEG is characterized by by low-voltage, high-frequency "alpha" and "beta" activity. Beta activity, low voltage and fast frequency, is also characteristic of Stage REM, or "dreaming sleep", which lacks alpha activity. But the deeper stages of sleep, such as Stage NREM, from which it is hard to awaken the person, are characterized by delta waves: high-voltage, low frequency.

18. The good feeling or "high" that comes from heroin, amphetamines, and possibly alcohol, probably arise because these drugs all seem to:

A. depress the brainstem regions related to REM sleep.

B. increase activity in various hypothalamic satiety regions.

C. increase dopamine release in the nucleus accumbens.*

D. block the transmission of pain signals as they enter the brain.

56%, .17. You didn't have to know anything about the nucleus accumbens. All you had to now that these addictive drugs all seem to be involved with the release of dopamine in the central nervous system.

19. The loud noises from your neighbor's party distract you from your studying. After some time, you are able to concentrate on your work even though the noise has not stopped or lessened. What process has likely occurred?

A. sensitization

B. habituation *

C. classical conditioning

D. instrumental conditioning

92%, .26. In classical conditioning, a conditioned stimulus is defined as one that does not by itself elicit a reflex, such as salivation (as to to meat powder US) or withdrawal (as to shock US). But any stimulus, when presented for the first time, will elicit reflexive startle and orientation responses. With repeated unreinforced presentation (that is, CSs that are not followed by USs), startle and orientation will gradually disappear. This is called habituation, and it is similar in some respects to extinction. The difference is that habituation occurs just to the CS, regardless of whether it is ever paired with a US. Sensitization is the opposite of habituation, where the organism's startle and orientation increase with repeated stimulation. In some views, habituation is the simplest form of classical conditioning, but it's not really, because there is no pairing of the CS with a US.

20. In classical conditioning, an unreinforced trial is one in which:

A. the CR does not occur.

B. the CS is not presented.

C. the US is not presented. *

D. the orienting action does not appear.

67%, .33. In classical conditioning, acquisition occurs when the CS is reinforced by the subsequent presentation of the US, and extinction occurs when the CS is no longer reinforced, because the US is no longer presented. The CR may well appear on an unreinforced trial -- before extinction has begun, before extinction is complete, on a test of spontaneous recovery, or in cases of partial reinformcement.

21. Thorndike likened his law of effect to evolution's law of the survival of the fittest. What actually survives according to the law of effect?

A. The "fittest" species.

B. The "fittest" individuals.

C. The "fittest" stimuli.

D. The "fittest" responses. *

82%, .28. Thorndike was very fond of this analogy, and so was Skinner. In their view, reinforcement "carved away" all irrelevant responses to a CS, so that all that remains is the CR that has been reinforced. Similarly, in natural selection the environment "carves away" at species, so all that remain are the ones that have characteristics that enable them to survive.

22. In an experiment, a dog undergoes 20 trials on which he hears a tone and gets meat powder in various combinations. On nine of the trials, he gets tone and meat powder; on 1 trial, he gets tone and no meat powder; on 1 trial, he gets meat powder and no tone; on 9 trials, he gets no tone and no meat powder. In this situation, there is:

A. a contingency between the sound of tone and meat powder. *

B. a contingency between the sound of the tone and absence of meat powder.

C. a negative contingency.

D. a zero contingency.

50%, .40. In the context of classical conditioning, c"ontingency" refers to the predictive relationship between the CS and the US. Consider the following table:

CS/US Status	US Occurs	US Does Not Occur
CS Occurs	9	1
CS Does Not Occur	1	9

In the example, the probability that the US will occur, given that the CS has occurred, is 0.9 (9/10). And the probability that the US will not occur, given that the CS has occurred, is 0.1 (1/10). When p(US | CS) is greater than P(US | no CS), then there is a positive predictive relationship between CS and US, and conditioning will occur.

23. The arbitrariness (or equipotentiality) principle in learning theory involves the assumption(s) that:

A. all mammals are capable of the same levels of cognition and performance.

B. mammals are capable of associating any response with any stimulus.*

C. certain CSs just seem to "go naturally" with particular USs.

D. all of the above

73%, .45. In neuroscience, equipotentiality refers to the idea that any part of the brain can perform any function -- an idea that is generally contradicted by evidence for specialization (localization) of function. In learning theory, the idea is very similar -- that any conditioned response can be attached to any conditioned stimulus. But another way, conditioning can occur between any arbitrarily selected stimulus and any arbitrarily selected response. This idea is contradicted by studies such as Garcia's investigations of taste-aversion learning, and Bolles' studies of species-specific defense rections, which show clearly that some stimulus-response connections are highly prepared and easy to learn; other S-R associations are unprepared, but learnable; and some S-R associations are contraprepared, and thus unlearnable even under optimal circumstances.

24. Which of the following is the most convincing evidence that an animal has learned by through "insight" rather than by trial and error?

A. a smooth, continuous performance

B. an absence of errors

C. a sudden drop in the learning curve

D. a transfer of training*

55%, .43. Good learning is indicated by an absence of errors regardless of whether the learning has occurred incrementally, through trial and error, or through insight. Insight learning is often characterized by a sudden change (not necessarily a drop) in the learning curve, compared to the smooth, continuous changes characteristic of "incremental learning. But a sudden change doesn't necessarily mean that insight has occurred. In fact, most individual learning curves are characterized by sudden changes in slope, marking the point where the individual organism makes the right response, gets reinforced, makes that response again, gets reinforced again, and then never makes the wrong response again. The smooth, continuous learning curves displayed in textbooks represent aggregates over a large number of subjects. The best evidence that the organism has "insight" into what has been learned, instead of simply associating some response with some stimulus, comes when the organism makes the learned response to a new stimulus, that it has never encountered before. Such "transfer of training" shows that the organism has moved beyond specific stimuli, and now "gets it".

25. A major problem with instincts and other species-specific behavior patterns is that:

A. they impair the species' ability to adapt to its usual environment.

B. they involve only small portions of the skeletal musculature.

C. they do not permit individual organisms to adapt to rapidly changing environmental conditions.*

D. they are only observed in primates and other "higher" vertebrates.

94%, .30. Instincts and other species-specific behaviors often involve the coordination of many parts of an animal's skeletal musculature. They are certainly more complex than either simple reflexes or simple taxes. Instincts evolved precisely to help the organism adapt to its environmental niche. The problem with instincts is that sometimes the environment changes rapidly, and there is not enough time for the species to evolve new species-specific behaviors. That's where learning comes in: learning permits individual species members (not species as a whole) to adapt their behavior to rapidly changing environmental circumstances. Classical conditioning (at least habituation) has been observed in every species with a nervous system that has been tested, even the most simple. Instrumental conditioning has been observed in every vertebrate species, not just primates like chimpanzees and us.

26. In classical conditioning, extinction occurs when

A. the organism responds to test stimuli other than those involved in the original acquisition trials.

B. response to a CS- shows the typical generalization gradient.

C. the CS is no longer paired with the US.*

D. the organism spontaneously recovers a variable-ratio schedule of reinforcement.

92%, .31. This is straight vocabulary -- but the vocabulary is critical, as extinction is a central concept in learning theory. Acquisition occurs when the CS is paired with the US, extinction occurs when the CS is no longer paired with the US. Response to new test stimuli would be generalization. Response to a CS- in discrimination learning, looks more like extinction than acquisition. But extinction doesn't have to involve a CS-. Extinction can occur with only a CS, when that CS is no longer reinforced. Spontaneous recover occurs after extinction.

27. The phenomena of spontaneous recovery and savings in relearning indicate that:

A. extinction generalizes, just as acquisition does.

B. extinction is similar to discrimination learning.*

C. classical conditioning underlies our emotional responses.

D. learned helplessness is easy to extinguish.

42%, .20. In discrimination learning, there is a CR to the CS+ but not the CS-, because the CS- does not predict the US. In extinction, the facts that the CR spontaneously recovers, and shows savings in relearning, show that the CS-CR association is not lost; rather, it is being suppressed, or inhibited, because the CS no longer predicts the US. In spontaneous recovery after extinction, the animal initially responds with a CR. If extinction trials continue, the CR quickly disappears. If the CS is reinforced once again, the CR is rapidly re-acquired. So, in a sense, in extinction the animal is learning to make a discrimination between previous trials, when the CS was reinforced by the US, and the current trials, when it is not.

28. Garcia's experiment on "taste-aversion" learning clearly violates all of the following assumptions of the traditional Stimulus-Response theory of learning except:

A. association by contiguity

B. arbitrariness.

C. empty organism

D. passive organism.*

26%, .19. A BAD ITEM, even though I discussed this point explicitly in class. In Garcia's experiment, bright, noisy water CS is paired with either shock or X-ray CSs. The sweet taste is just as contiguous with the shock as is the sight and sound, but no conditioning accrues to the taste. Similarly, the sight and sound is just as contiguous with the X-ray as the taste, but conditioning accrues only to the taste. Therefore, conditioning can't occur by virtue of association by contiguity. Not to mention that there is a long delay between taste and nausea, which also violates association by contiguity. The same facts violate arbitrariness: apparently taste can't be associated with shock, and sight and sound can't be associated with nausea. The implication of the taste-aversion studies is that we can't treat the organism as if it were an empty "black box". We have to understand something about is biological structure, a product of its evolutionary history, to understand what it can learn and what it can't. The only assumption left is the passive organism. The Garcia experiments don't really say anything about the animal's active involvement in the learning process: that point is made much more clearly by experiments like Kamin's on the blocking effect.

29. Which of the following procedures violates the principle of association by contiguity?

A. The standard paradigm for classical conditioning.

B. Simultaneous conditioning.*.

C. Delay conditioning

D. Trace conditioning.

36%, .03. A BAD ITEM, even though I also discussed this point explicitly in class. In the standard paradigm, the CS precedes the US by a short interval; thus, the two stimuli occur relatively close together in time. The standard paradigm gives good conditioning, which is consistent with the principle of association by contiguity. In delay conditioning, the onset of the US occurs some time after the onset of the US. Conditioning also occurs in the delay case, but because there is still some temporal overlap between CS and US, this is consistent with association by contiguity. In trace conditioning, the offset of the CS precedes the onset of the US, but because the two stimuli still occur relatively close together, the fact that conditioning occurs is not really trouble for association by contiguity. The real problem for association by contiguity comes from simultaneous conditioning, which doesn't occur despite the fact that the CS and US are precisely contiguous. The failure of simultaneous conditioning to occur is the first hint that associations aren't formed by a principle of contiguity. The results of all four procedures -- conditioning in the standard, delay, and trace cases, no conditioning in the simultaneous case -- is, however, consistent with the principle of association by contingency. In the first three cases, the CS predicts the US. In the simultaneous case, the CS is redundant with the US.

30. In a signal-detection experiment, the payoff matrix is established as follows: + 5 for a hit; +5 for a correct negative; -5 for a false alarm; and -15 for a miss. In order to maximize his "winnings," the research participant should establish a criterion:

A. biased toward answering yes. *

B. biased toward answering no.

C. equally biased toward yes and no.

D. biased toward saying maybe.

47%, .38. Signal-detection theory is a paradigm that attempts to incorporate "higher" mental processes such as expectations and motives into the analysis of even very simple sensory functions, such as detecting small changes in environmental stimuli. In general, we vary the subjects' expectations by varying the proportion of "signal" on trials. If the signal is actually presented 9 out of 10 times, under conditions of uncertainty your best guess is that a signal was actually presented. If the signal is only presented 5 times out of 10 trials, you don't really have a basis for forming an expectation. And in general, we vary motivation by varying the payoff matrix -- the consequences for hits, misses, and false alarms. Similarly, if you are rewarded for a hit but not penalized for making a false alarm, you will be motivated to say "yes" -- if the signal is actually on you win, but if the signal is actually off, you don't lose anything. But if you are penalized for making false alarms, you'll be more conservative, less likely to say "yes" unless you are pretty sure. So now consider the following table:

Stimulus Status/Subject Response	"Yes, It's On"	"No, It's Off"
Signal On	Hit, +5	Miss, -15
Signal Off	False Alarm, -5	Correct Rejection, +5

What really counts are the consequences for hits vs. false alarms. If you say "yes", and you're wrong (a false alarm), you get penalized a little. But if you say "no", and you're wrong (a miss), you're penalized a lot. Therefore, you're going to be biased toward saying "yes", and away from saying "no", when you're uncertain.

31. A pheromone is:

A. any olfactory stimulus that has a specific meaning for a given organism, such as carrion for a hyena.

B. a special chemical substance secreted by a given organism that produces a particular reaction in another member of the same species. *

C. any chemical substance, such as sweat, that provides a distinct olfactory stimulus for another member of the same species.

D. a built-in, species-specific signal that advertises sexual receptivity.

42%, .24. Phermones are chemical substances that elicit particular instinct-like reactions in members of the same species. The best-known pheromones might elicit sexual responses, but the response to a pheromone is not necessarily sexual. In any case, the pheromone-response connection is a product of evolution, and is universal within a species. There are lots of meaningful olfactory stimuli that aren't pheromones, not least because the meaning isn't the same for everyone: the smell of cinnamon might bring Christmas to mind for some of us, but the same smell might have a very different meaning for Jews, Muslims, or Buddhists. A stimulus like sweat can elicit many different kinds of responses, ranging from disgust to sexual arousal, depending on the circumstances, and one's personal history with (and beliefs about) sweat, but the thing about pheromones is that they elicit one particular responsefrom everyone.

32. In the theory developed by Hurvich and Jameson there are __________ primary color qualities, which are organized in opponent-process pairs.

A. 4

B. 10

C. 8

D. 6*

48%, .16. A BAD ITEM. In the opponent-process theory of color vision, there are six primary color qualities -- red, green, yellow, blue, black, and white, and these are organized into three opponent-process pairs: red/green, yellow/blue, and black/white -- giving rise to phenomena such as negative afterimages. Remember, black and white are colors too, interacting with the other colors to produce saturation.

33. Binocular disparity means that:

A. there is feedback from the strain on the eye muscles.

B. gradients of texture cannot be depth perception cues.

C. the images falling on the retinas of each eye differ slightly.*

D. some depth perception cues conflict.

90%, .36. Binocular disparity is the stereoscopic cue to depth or distance that relies on the fact that an object casts a somewhat different image on the retina of each eye. The fusion of these disparate two-dimensional images creates a representation of three-dimensional space. Feedback from the eye muscles underlies the ocular depth cues of convergence and accommodation. Some depth perception cues may conflict, giving rise to ambiguities or illusions, but this doesn't have anything to do with binocular disparity.

34. A neon sign for a bowling alley has flashing lights that make it seem like a ball has gone down the alley and knocked over some pins. This illusion of motion is called:

A. induced movement.

B. motion parallax.

C. apparent movement.*

D. optic flow.

49%, .32. This was pretty much definitional. Neon signs, movies, and video all depend on apparent movement to give the illusion of motion. Induced movement is what appears when you press gently on your eyelid, displacing the image of an object on your retina. Motion parallax refers to the fact that, when we move our heads, the retinal images of nearby objects move more than those of more distant ones.

35. The Gestalt group of psychologists are most well known for their work on:

A. adjustment to stressful perceptual situations.

B. the development of thought processes as they influence perception.

C. issues of free will and personal responsibility.

D. organizational processes in perception.*

64%, .42. This was pretty much definitional, but the Gestalt movement is very important to understanding perception, because they were among the first to argue that perception wasn't governed entirely by stimulus information. For the Gestaltists, "the whole is greater than the sum of its parts" means that the entire percept can be reduced to its elementary features. Rather, it is the organization of these elementary features (via Gestalt principles such as proximity and similarity) that gives rise to perception. The Gestaltists weren't so much interested in the role of thought in perception, though. In their view, the Gestalt principles followed from the way the perceptual system of the brain is organized. Still, because brain structure is important, perception goes "beyond the information given" by the stimulus.

36. Which of the the following illustrates or assumes that perception involves both top-down and bottom-up processing?

A. bidirectional models

B. impossible figures

C. the perceptual hypothesis

D. all of the above*

54%, .16. Bidirectional models describe both the "bottom-up" and the "top-down" processes in perception (or attention, for that matter). The impossible figures illustrate the bidirectional nature of perceptual processing because these figures look OK so long as we don't try to connect up each itty-bitty part of the object (perceived through bottom-up processes) with the global perception of the object (perceived through top-down processes). Perceptual hypothesis-testing illustrates bidirectionality because the hypothesis influences the search for evidence (top-down), while the evidence obtained tends to confirm, disconfirm, or revise the hypothesis (bottom-up).

37. The unconscious inference proposed by Helmholtz:

A. takes distance into account when judging size.

B. can explain size constancy.

C. is similar to aspects of modern perception theories.

D. all of the above*

71%, .34. Size constancy (B) takes distance into account when judging size (A). Helmholtz' theory is similar to those modern perception theories that argue that hypothesis-testing, inference, and problem-solving activity is important for perception. The only difference is that Helmholtz thought that these processes were automatic and unconscious, whereas many later cognitive theories of perception allowed the inferences to be conscious as well. Both Helmholtz and later theoriests believed that "higher" mental processes of judgment and inference were involved in perception -- as opposed to Gibson, who thought that perception was derived entirely from stimulation, without any need for cognitive activity.

38. The Renaissance masters tried to paint pictures that would:

A. correspond to the image the model cast on the eye. *

B. represent enduring and characteristic attributes of the model.

C. convey the momentary impression the scene produced in the artist's mind.

D. indicate what the model looks like, not just from one orientation but from several different ones.

56%, .34. Just as psychology has a history, psychology also has connections to other fields, and not just biology. There is a very large body of literature, for example, on the connections between visual art (chiefly painting) and the psychology of perception. I think especially of the work of Gombrich. Anyway, the whole point of Renaissance theories of art is that a painting should be like the scene it represents, as if it were viewed through a window (represented by the frame). True, the Renaissance artists focused on mythological, Biblical, or idealistic scenes, but they were still painted in such a way as to reproduce the image cast by the scene on the eye. In fact, Renaissance treatises on visual perspective helped later psychologists formulate theories of depth perception (see, for example, a book on this subject by Kubovy). Later painters turned to more realistic, everyday themes, but until well into the 19th century this concern with reproducing the image that would appear on the retina remained paramount. Other artistic traditions, for example in China and Japan, took a very different approach to perspective, which is why many Chinese and Japanese scroll paintings appear a little strange to a Western-trained eye. Many ancient artistic traditions, such as that of ancient Egypt, focused on characteristic attributes, which is one reason that the figures in Egyptian art are so often found in such strange poses. The Impressionists, strongly influenced by the emerging psychology of perception (Seurat, discussing one of his famous pointillistic paintings, were interested in representing momentary sensory-perceptual experiences -- it's where the term "Impressionism" comes from. And Picasso and other cubists were interested in incorporating more than one perspective or vantage point into their paintings -- which is what the term "Cubism" is all about: there is an attempt to view the object or scene from many vantage points around the three dimensions of physical space, rather than to portray 3D space from a single vantage point.

39. The perception of movement: occurs when an object's image traverses the retina when the eyes and head remain stationary. This illustrates the operation of the _____ system for motion perception:

A. image-retina

B. eye-head system

C. both A and B.*

D. neither A nor B.

14%, -.06. A BAD ITEM. Maybe a little tricky, but the point is an important one. Information about the movement of the image across the retina is provided by both the image-retina system and the eye-head system. It's the discrepancy between the two sources of information that is the real stimulus for the perception of motion. When the image moves across the retina (information supplied by the image-retina system), but the eyes and head remain steady (information provided by the eye-head system), we see movement. But we also see movement when the image is stationary on the retina (information provided by the image-retina system) but the eyes and/or head move (information provided by the eye-head system). Remember, in Gibson's ecological view of direct perception, it is the total pattern of stimulation in the environment that gives rise to a percept.

40. The effects of superposition (or interposition) illustrate the role of _____ cues in the perception of depth or distance:

A. binocular, ocular

B. binocular, optical

C. monocular, ocular

D. monocular, optical*

41%, .43. Superposition is an optical or pictorial cue for the perception of distance, because it's a cue that can be used to give the appearance of depth to a 2-dimensional space. Artists use it any time they obscure one object with another to give the impression that the first is behind the second. It's a monocular cue because it works even if you view an object through only one eye. Accommodation is a monocular cue (you don't need two eyes), while convergence is a binocular cue (no convergence without two eyes to do the converging). There really aren't any binocular optical cues except maybe retinal disparity, which is better classified as a stereoscopic cue than as an optical or pictorial cue.

41. Reversible figures such as the "goblet/profile" show that:

A. all the information necessary for perception is supplied by the stimulus in its ecological context.

B. the same stimulus information can give rise to two or more different percepts.*

C. perception remains stable despite variance in the stimulus array.

D. people from different cultures employ different physiological systems in perception.

91%, .38. Reversible figures are those in which the same stimulus information can support two quite different percepts. Therefore, they are classic demonstrations that perception isn't just a matter of extracting information from a stimulus -- there have to be other factors involved, such as what the perceiver expects, what s/he's paying attention to, and the like. In a sense, the reversible figures are the opposite of the constancies, in which perception remains constant (hence their name) despite varying stimulation. In either case, perception is not inextricably tied to stimulation.

42. Perceptual illusions (such as the Muller-Lyer "feathers/arrows" figure show that:

A. perception is shaped by higher mental processes such as unconscious inferences.*

B. perception reflects conscious, deliberate problem-solving activity.

C. perception involves extracting information from the distal stimulus.

D. the "magno" and "parvo" systems interact to produce conscious perception.

64%, .39. Apparently, the Muller-Lyer illusion is created because the perceiver automatically and unconsciously perceives the "feather" figure as further away than the "arrow" figure, because the feathers look like the convergence lines that create the illusion of depth. Because the two lines cast images of the same length on the retina, the perceiver automatically and unconsciously invokes the size-distance rule to infer that the "feather" figure must be longer than the "arrow" figure -- or else its retinal image wouldn't be so large. The whole illusion is produced by inferences, but if you were conscious of these inferences, you wouldn't experience the illusion. And if all you were doing was extracting information from the stimulus, particularly the retinal images of the lines, without making any inferences about depth and size, then you wouldn't experience the illusion at all. The magno and parvo cells in the retina are involved in color and brightness sensation, respectively.

43. Informal and unsystematic data collection is problematic because it can be biased by:

A. the file-drawer problem.

B. memory errors.

C. a confirmation bias.

D. all of the above*

85%, .20. There are lots of problems with unsystematic data collection. If contrary data has been filed away, you'll never find out about it. If you rely on memory, you may remember instances that confirm your hypothesis better than instances that disconfirm it (or, for that matter, vice-versa -- both are examples of bias). And you may be disposed to seek evidence that will confirm a hypothesis, while ignoring evidence that disconfirms it. All of these problems can be reduced, if not entirely eliminated, by a formal, systematic method of data collection.

44. Which of the following can resolve causal ambiguity in a correlational study?

A. calculating the variance around the mean

B. a specific time-order relationship between variables*

C. an increase in external validity

D. reduction in the number of participants

44%, .34. Correlation shows the strength and direction of association between two variables, but by itself it cannot yield conclusions about causes. A might be correlated with B because A causes B, because B causes A, or because both A and B are caused by a third factor, C. However, because causes precede effects pretty much by definition, if A precedes B then we can infer with some confidence at least that B hasn't caused A. Increasing external validity won't help, because external validity simply has to do with the correspondence between the laboratory testing situation and the real-world situation ostensibly represented by the laboratory model.

45. What can you say about a research study in which the participants are representative of a larger population of people and the research stimuli are representative of those encountered in the real world?

A. The research study is internally valid.

B. The research study is externally valid. *

C. both a and b

D. none of the above

40%, .21. Here's where external validity comes in. If the subjects who participate in a research study aren't representative of people in the real world, then the study might tell us something about the subjects, but can't tell us much of anything about the real world outside the laboratory. Critics sometimes reject animal experiments as externally invalid on the grounds that rats and pigeons aren't people (ignoring the fact that our brains, for example, work pretty much the same way). And critics sometimes reject experiments on "college sophomores" on the ground that they're not representative of "real people" (ignoring the fact that college sophomores are people too). But an experiment that used only males as subjects might not be externally valid, if used to generalize about the population as a whole, including women. For example, we now know that the "flight or fight" reaction to stress is a little exaggerated, because "flight or fight" is more characteristic of males, while "tend and befriend" is more characteristic of females. If we used only males (rats or people) in our studies of stress reactions, we'd never know that "flight or fight" isn't universal.

46. Based on what you know about the benefits of double-blind studies, which of the following ethical principles for the conduct of psychological research is most likely to conflict with a researcher's desire to conduct an internally valid research study?

A. informed consent*

B. confidentiality

C. avoidance of coercion

D. the right to cease participation

52%, .41. A double-blind study is one in which neither the experimenter nor the subject knows what treatment the subject (say, a cancer patient enrolled in a clinical trial) knows what treatment the subject is getting (say, an active drug or a placebo). Double-blind clinical trials are very important tools for medical research, but they necessarily entail a problem with informed consent, because the patient doesn't know exactly what treatment s/he's getting. Patient's give informed consent to participate in the clinical trial to begin with, knowing that they might get placebo rather than an active drug, but that's not entirely the same thing. The double-blind method is an excellent way of conducting a clinical trial, because it insures internal validity -- we know for sure, on the basis of the results, whether the drug works. But the people who volunteer for a clinical trial, knowing that they won't know for sure what treatment they're going to get, may be unrepresentative of patients with the disease in general. Therefore, the internally valid clinical trial may lack some degree of external validity.

47. A researcher chooses 20 works of art and randomly numbers them from 1 to 20. She then asks people to write down the numbers assigned to the three works they like the most out of the 20. The numbers they write down form a(n):

A. categorical scale.*

B. ordinal scale.

C. ratio scale.

D. interval scale.

47%, .22. Because of random assignment, the numbers assigned to the objects have no intrinsic meaning. They just label the objects. Therefore, this "scale" is categorical in nature. If the numbers had meaning, representing different magnitudes on some dimension (even good vs. bad art), then we would have an ordinal scale, and maybe even an interval or ratio scale. If the subjects used numbers to express their aesthetic preferences, we would be talking about interval scales (at least). But because they only use numbers to identify which paintings they like, we are talking about a categorical scale.

48. In the distribution, 1 2 5 7 7 9 10 10 10 12, the mean is approximately:

A. 11.

B. 7.*

C. 10.

D. 8.

89%, .21. IN fact, the mean is exactly 7.3 (73/10). The median is 8 (50% of the observations above, and 50% below, this value). And the mode most frequent observation) is 10. The range of scores is 11 (12-1).

49. If two variables are positively correlated, then:

A. increasing values of one variable are associated with increasing values of the other variable.*

B. increasing values of one variable are associated with decreasing values of the other variable.

C. each value of one variable is identical to each value of the second variable.

D. their line of best fit slips downward.

97%, .28. The correlation coefficient (there are several varieties) expresses the strength and direction of the relationship between two variables. In positive correlations, the two variables move together: as one goes up, the other goes up; as one goes down, so does the other. A scatterplot of the two variables will produce a trend line that runs from the lower left-hand corner to the upper right-hand corner. In negative correlations, the two variables move in opposite directions: as one goes up the other one goes down, and vice-versa, producing a trend line that goes from the upper left-hand corner to the lower right-hand corner. In either case, the strength of the relationship -- or, put another way, the extent to which one variable can be predicted from the other -- can be represented by an envelope drawn around the scatterplot. The narrower the envelope, the higher the correlation (positive or negative).

50. A distribution has a mean of 105 and a standard deviation of 20. Which of the following scores probably comes from a different distribution?

A. 60*

B. 90

C. 100

D. 135

83%, .34. The 95% confidence limits for a distribution comprise two (2) standard deviations on either side of the mean. 10-40 = 65, and 105+40 = 145. Therefore, any score lower than 65, or higher than 145, likely comes from a different distribution. To answer this question correctly, all you needed to remember was the "rule of 2 standard deviations" underlying conventional standards for statistical significance.