University of California, Berkeley
Department of Psychology

Psychology 1
Fall 2004

Midterm Examination 1

In the exam that follows, correct answers are marked with an asterisk (*).

The exam was initially scored to identify bad items. There were four such items where less than 50% of students got the correct answer, and performance on the item did not correlate with performance on the rest of the exam:

Items # 14, 33, 37, and 46.

These items were then rescored as correct for all responses.

On the initial scoring of the exam, the mean score was 33.95, or 68% correct. This is well within the range of my exams in Psychology 1, which is an average score of 65-70% correct. Rescoring the four bad items raised the mean score to 38.2, or 76% correct, which is very good indeed.

No other items will be rescored.

The scoring key below provides the correct answers to each item, along with a statistical analysis and an explanation of the correct response.

Choose the best answer to each of the following 50 questions. Questions are drawn from the text and lectures in roughly equal proportions, with the understanding that there is considerable overlap between the two sources. Usually, only one question is drawn from each major section of each chapter of the required readings; again, sometimes this question also draws on material discussed in class. Read the entire exam through before answering any questions: sometimes one question will help you answer another one.

Most questions can be correctly answered in one of two ways: (1) by fact-retrieval, meaning that you remember the answer from your reading of the text or listening to the lecture; or (2) inference, meaning that you can infer the answer from some general principle discussed in the text or lecture. If you cannot determine the correct answer by either of these methods, try to eliminate at least one option as clearly wrong: this maximizes the likelihood that you will get the correct answer by chance. Also, go with your intuitions: if you have actually done the assigned readings and attended the lectures, your "informed guesses" will likely be right more often than they are wrong.

Be sure you are using a red Scantron sheet.

Fill in the appropriate circles with a #2 pencil only.

Be sure you put your name on the front of the red Scantron sheet.

Be sure you put your Student ID# on both sides of the red Scantron sheet.

Indicate Exam 001 on the reverse side of the red Scantron sheet.

Retain this exam, along with a record of your answers.

1. Psychology is a biological science because

A. behavior is controlled by genetic influences.

B. the brain is the physical basis of the mind.*

C. the endocrine system permits one part of the body to influence another.

D. the nervous system is a physico-chemical system.

87% of the class got this item correct, and the question's item-to-total correlation was rpb = .12. Some aspects of behavior seem to be under some degree of genetic control, but the real reason that psychology is a biological science is that "the mind is what the brain does". Remember, though, that the beauty is psychology is that it's not just a biological science; it's also a social science. And a cognitive (and an affective, conative, and behavioral) science, and even a physical science.

2. A hypothesis is testable if

A. it can be confirmed.

B. it can be disconfirmed.*

C. it is sufficiently vague.

D. virtually any set of circumstances could support it.

25%, .21. This was a difficult item, but the item-to-total correlation confirmed that it was appropriate for the test. Hypotheses are derived from broader theories, and they're testable if they make some observable prediction. A hypothesis that could be supported by virtually any data is scientifically worthless, because there's no way it could be disconfirmed.A plurality of students (42%) went for A. But while it's true that a hypothesis must be stated in empirically observable terms, so that it might be confirmed, it is more important that there be standards for disconfirming the hypothesis. The point here is very important, which is that there's lots of evidence that might confirm a hypothesis, in the sense of being consistent with it. Therefore, experimental research should be constructed in such a way as to actively search out evidence that might disconfirm the hypothesis.

3. What is the primary purpose of random assignment?

A. To ensure that experimental and control groups start out with the same number of subjects

B. To ensure that experimental and control groups start out with different numbers of subjects

C. To ensure that experimental and control groups start out identical to each other*

D. To ensure that experimental and control groups will end up different from each other

71%, .38. A lot of you went for D, but random assignment is intended to insure equivalence of the experimental and control groups before the independent variable (IV) is manipulated. If the IV has an effect, the two groups will end up different from each other. But we can only conclude that the IV has an effect if they started out equivalent. That's what random assignment is supposed to accomplish: to ensure that groups that might end up different from each other didn't start out that way.

4. If a study's subjects are representative of the population as a whole and its stimuli are representative of stimuli encountered in the real world, then the study is said to have

A. internal consistency.

B. internal validity.

C. external validity.*

D. external consistency.

86%, .27.Internal consistency has to do with the degree to which test items hang together to bear on a single construct. It's why, for example, we want each individual test item to correlate with total test score: items that don't correlate don't belong on the test. I don't think there is such a thing as external consistency. Internal validity simply means that there are no factorsin the experiment, such as confounds, that would produce invalid results. External validity has to do with the extent to which we can generalize the results of an experiment to the real world outside the laboratory. For that, we need to have subjects and stimuli that are representative of the real world.

5. Afferent is to efferent as _________ is to _________.

A. up; down

B. sensory; motor*

C. reflex; decision

D. integration; reaction

61%, .20. Afferent neurons, and afferent nerves, carry sensory messages from the sense organs to the central nervous system. Efferent neurons, and efferent nerves, carry motor messages from the central nervous system to the effector organs. There may be a sense in which central is "up" and peripheral is "down". But the optical nerve (afferent) and the facial nerve (efferent) go sideways, if you think about it, as do the spinal nerves (which are both afferent and efferent). The afferent tract of the spinal cord goes "up" to the brain, and the efferent tract goes "down" from the brain, but only in those vertebrates who walk upright (which isn't too many). The important distinction here is not spatial, it's functional: the difference between between sensory and motor functions.

6. A general characteristic of the primary motor area is that

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

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

C. primary motor areas are localized in only two lobes of the cerebral hemispheres.

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

86%, .38. Remember the principle of proportional representation -- for both afference and efference, more cortical mass is devoted to those areas of the body that require acute sensitivity or fine motor control. The motor and somatosensory areas are in different lobes -- frontal and parietal, respectively.

7. From what you know about the position of the various brain areas, which of the following seems most probable?

A. Damage to Wernicke's area is more likely to be accompanied by paralysis than is damage to Broca's area.

B. Damage to Wernicke's area is more likely to be accompanied by deafness in the left ear than in the right ear.

C. Damage to Broca's area is more likely to be accompanied by paralysis of the left arm than by paralysis of the right arm.

D. Damage to Broca's area is more likely to be accompanied by paralysis than is damage to Wernicke's area.*

54%, .36. Remember that Broca's area is located adjacent to the primary motor cortex. Wernicke's area is located much further away, in the temporal-parietal area, so it would be less likely to involve paralysis. Now, conceivably, damage to Wernicke's area could spread to include the primary auditory cortex in the temporal lobe, but since Wernicke's area is in the left hemisphere, this would result in deafness to the right ear.

8. Which of the following would be the best evidence that the right hemisphere understands some language?

A. People with a severed corpus callosum can respond to simple written commands presented in their left visual fields.*

B. Most normal right-handed people can write awkwardly with their left hands.

C. People with a severed corpus callosum can answer questions heard by either ear.

D. Strokes in the left hemisphere of right-handed people severely disrupt language understanding.

77%, .21. Remember that the left visual field is processed by the right cerebral hemisphere. Therefore, if the patient could respond to written language presented in the left visual field, that would mean that the right hemisphere had some capacity to process language. Which it does, at least in some people.

9. What major part of the brain development takes place after a human infant is born?

A. The brain is split into separate lobes

B. 20�80% of neurons in the brain die off (depending on the brain region)

C. Connections between various neurons are wired*

D. Neutrophic factors cause brain cell differentiation

54%, .14. The brain is already structured at birth, at least so far as the hemisphere and lobes are concerned. Neurotrophism (sic) has to do with how individual neurons develop; this is accomplished during gestation, as is the "death" of newly formed brain cells, so that the newborn enters the world with a complete set of brain cells. What happens after birth is that these neurons continue to connect themselves up to each other.

10. Spinal reflexes are:

A. innate, automatic, responses to stimulation.*

B. unaffected by neurotransmitter reuptake.

C. voluntary behaviors.

D. weaker in patients suffering from paraplegia.

93%, .26. Spinal reflexes are unlearned, automatic involuntary responses to stimulation; and they are stronger in paraplegics, because they cannot be dampened by modulatory signals ordinarily sent from the brain to spinal centers.

11. In young children, recovery of speech and other brain functions following injury is more likely than it is for adults. Thus, we say that a child's brain has _________ than an adult's.

A. less specificity

B. more specificity

C. less plasticity

D. more plasticity*

87%, .27. For all intents and purposes, brain cells don't regenerate, so that other brain areas have to take over the functions usually performed by those which have been damaged. There's apparently considerable redundancy in the brain, so far as localization of function is concerned, so if the brain damage occurs before its structure is "fixed", recovery of function can occur when some other brain structure takes over the lost structure. But after the brain matures it loses much of its flexibility in this respect, and the prospects of recovery are much dimmer..

12. What can be said of a negative feedback system?

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.

91%, .29. This was purely definitional: negative feedback slows or stops the process that produced it, while positive feedback starts it or increases it. Homeostatic regulation is an example of negative feedback: departures from homeostasis lead to a return to homeostasis.

13. Lesions in the hippocampus, as in the case of Patient H.M., are associated with:

A. problems in memory.*

B. problems in emotion.

C. problems in understanding language.

D. problems in maintaining wakeful, alert consciousness.

97%, .28. H.M. has memory problems because of damage to his hippocampus and related structures in the medial (interior) portion of the temporal lobe. S.M. has emotional problems because of damage to her amygdala. Language problems would be produced by damage to Broca's or Wernicke's areas. Coma is produced by damage to the thalamus or to the midbrain reticular formation.

14. A patient who has lost tactile sensitivity in her right hand as a result of stroke is also likely to have lost:

A. tactile sensitivity in her left hand.

B. voluntary movement of her right foot.

C. tactile sensitivity in her left arm.*

D. voluntary movement of her left foot.

2%, -.03!, a really bad item. That's because of a typo, which I didn't catch on proofreading. Sorry. B is the only answer that is even remotely correct, and that's what 89% of you said, which was good. But it wasn't the concept I was going for, so instead of redoing the key, we rescored this item correct for all responses. Anyway, I was looking for an application of the principle of regular representation -- that the somatosensory area for the right arm would be near those for the right hand, and thus also likely to be damaged.

15. With which bodily function is the sympathetic nervous system most concerned?

A. Vegetative functions

B. Slowing of the heart

C. Activation*

D. Digestion

86%, .35. The sympathetic branch of the autonomic nervous system increases arousal -- activation -- and "flight or fight" responses to threat or stress. Heart rate increases, digestion shuts off. The parasympathetic branch runs the vegetative functions, like digestion, and also acts in opposition to the sympathetic branch during stress -- by, for example, slowing heartrate.

16. How do humans and animals differ in their sexual response?

A. Human females are under strict hormonal control, but female animals are not.

B. Female animals are under strict hormonal control, but human females are not.*

C. Human males are reliant on testosterone for sexual arousal, while male animals are reliant on progesterone for sexual arousal.

D. Human males are reliant on progesterone for sexual arousal, while male animals are reliant on testosterone for sexual arousal.

62%, .47. As a rule, sex among nonhuman animals is obligatory, instinctual, and solely in the service of procreation. So most animals copulate only for purposes of breeding -- females become receptive in response to changes in their internal hormonal environment; and males become sexually active in response to signs of receptivity in females. But human sex is optional, and humans have sex even when they're not trying to procreate, and largely independent of the female's hormonal state. But you probably noticed this! Testosterone is a male sex hormone, regardless of whether the organism is a human or a nonhuman animal.

17. Which mechanism(s) control(s) sleep and waking cycles?

A. The parasympathetic system

B. The sympathetic system

C. Structures in the mid- and hindbrain.*

D. The hypothalamus

54%, .20. The sleep-wake cycle is largely controlled by the reticular formation, pons, and related structures in the midbrain and hindbrain. The sympathetic and parasympathetic nervous systems control autonomic functions, while the hypothalamus controls homeostatic regulation.

18. Which of the following presents evidence against drive-reduction theory?

A. Monkeys will solve puzzles without being rewarded for doing so.

B. Rats enjoy drinking artificially sweetened water even though it lacks nutritive value.

C. Many humans enjoy roller coasters.

D. All of the above.*

62%, .16. Drive reduction theory holds that behavior is motivated by a "desire" to return the organism to homeostasis -- no hunger, no thirst, no pain, etc. No arousal. No stimulation. So monkeys shouldn't do anything without reward, and rats shouldn't be interested in any substance that doesn't supply nutrients, and humans shouldn't want to get themselves aroused.

19. Natural selection refers to the process or principle

A. whereby organisms identify mates of their own species.

B. whereby animals avoid potentially harmful foods.

C. that explains how environmental factors limit natural resources.

D. that explains why organisms with certain hereditary attributes will eventually outnumber organisms who lack these attributes.*

94%, .34. This was definitional: natural selection is the process by which evolution favors organisms whose traits increase their reproductive fitness. Darwin's model for this was the artificial selection practiced in animal husbandry, whereby farmers selectively breed livestock with certain desirable traits, and prevent others from breeding at all.

20. In most animal species, the final choice of a mate is made by

A. the male, who usually initiates courtship.

B. the female, who bears the major costs of reproduction.*

C. both male and female equally, during courtship.

D. the arbitrary mechanisms of chance.

90%, .36. This was one of the great discoveries of the 1970s. Previously it was believed that females were more-or-less passive recipients (or, if you will, victims) of males' sexual attention. But it turns out that, for nonhuman animals at least, it's the female who determines which male will successfully mate with her. The general explanation of this fact is that females bear the major costs of reproduction -- bearing offspring and taking care of them into adulthood -- and so they're "choosy".

21. Evolutionary theorists argue that

A. men should be more jealous over sexual than emotional infidelity.*

B. men and women should both be more jealous over sexual than emotional infidelity.

C. men and women should both be more jealous over emotional than sexual infidelity.

D. men should be more jealous over emotional than sexual infidelity.

71%, .38. This is one of the most highly touted predictions of evolutionary psychology. The theory is that females always know whose children are theirs, because they deliver them. But males don't, because the female could have been impregnated by another male. When it comes to human sexual behavior, then, men are more concerned with sexual than with emotional fidelity -- they don't care whom their wives love, so long as they are certain that the children they raise are their own. The evolutionary psychologists go further to propose that women are more concerned with emotional than with sexual fidelity -- they don't care whom their husbands sleep with, so long as they support and protect them and their children. There's some data to support this prediction, but it's still very controversial, and how the data comes (sic) out depends crucially on details of methodology. For example, if you force people to choose, the results come out as predicted. But if you allow people to rate the outcomes independently, they rank them about equally.

22. Birds feed their young because

A. they are genetically programmed to do so.*

B. they know that this is the only way their genes will survive.

C. they are imitating the behavior in which they saw their own parents engage.

D. the baby birds will return the favor when the parents are too old to gather their own food.

60%, .19. Parenting behavior in birds is neither cognitive or conscious. The adult birds don't know anything about what their young need, and they don't even "want" to feed them. They just feed their young in response to releasing stimuli provided by the young themselves, as in the bill-pecking behavior of herring-gull chicks. And the adult birds don't learn to do this, either through trial and error or through observational learning -- feeding behavior occurs the first time the releasing stimulus is presented, with no acquisition process. Obviously, in evolutionary terms adults feed their young so that their genes will be passed on, but they don't "know" this -- it's just an instinctive, automatic, fixed action pattern.

23. Neurological evidence concerning the relationship between predation and aggression indicates that, in cats,

A. both behaviors are elicited by stimulation of the same hypothalamic area.

B. each behavior is elicited by stimulation of a different area of the hypothalamus.*

C. both behaviors are elicited by stimulating an area of the hypothalamus that controls eating.

D. aggression, but not predation, is elicited by stimulating an area of the hypothalamus that controls eating.

69%, .38. Predation is against members of other species, and it results in death; it's about eating your prey. Aggression is against members of the same species, and it rarely results in death -- the loser just leaves the winner's territory; it is essentially sexual in nature. Interestingly, the two behaviors -- which are both forms of fighting, after all -- are controlled by different areas of the hypothalamus. Further, the area that controls predation is near the area that controls eating, but the area that controls aggression is further away.

24. Repeating a spoken word will activate all the following areas of the brain except:

A. the occipital lobe.*

B. the frontal lobe

C. the parietal lobe.

D. the temporal lobe.

80%, .29. Remember the occipital lobe contains the primary visual cortex. It will be activated when repeating a written word (and the primary auditory cortex of the temporal lobe will be relatively silent). The frontal and parietal lobes aren't really involved in either hearing or reading, but Wernicke's area will be activated by with spoken or written language. The motor cortex of the frontal lobe will be activated by speaking either a spoken or a written word.

25. Karl has a tumor that has destroyed much of his amygdala. In a classical conditioning study, he is given an electric shock whenever a blue light flashes and no shock when a yellow light flashes. Most likely, he will be

A. unable to distinguish between the two lights and will not fear either.

B. unable to distinguish between the two lights and will fear both.

C. able to state that the blue light is accompanied by shock, but he will not fear the blue light.*

D. afraid of the blue light but not the yellow light.

88%, .36. Remember that damage to the amygdala impairs emotional responses, but not learning per se. Therefore, Karl will be able to learn the purely "cognitive" fact that the light predicts shock, but he will not show much emotional response to either the light or the shock.

26. What problem is associated with instinctive behavior?

A. It does not enable species to adapt to their environmental niches.

B. It does not permit individual organisms to adapt to changing environments.*

C. Instinctive behaviors are ultimately maladaptive.

D. Evolutionary mechanisms only permit learning by trial and error.

83%, .38. Instinctive behavior is wired into whole species over the course of evolutionary time, as they adapt to the environments in which they find themselves. This process takes generations, many generations. So instinctive behaviors are adaptive by definition -- so long as the environmental niche in which they evolved doesn't change. There's no way that evolution will help individuals adapt to environmental change. Organisms that happen to have traits that enable them to adapt to the environmental change will survive and reproduce, thus passing on those traits to the next generation, and those that don't will just die without reproducing -- or will reproduce without passing adaptive traits to their offspring. The species evolves, not the individuals. The only way that individual organisms can adapt to changing environmental circumstances is by learning to do so -- a process that often, but not always, involves trial and error. Interestingly, what an individual learns must be passed on to the next generation through learning -- there's no inheritance of acquired characteristics.

27. A(n) _________ is elicited by a stimulus regardless of an animal's history of experiences.

A. unconditioned reflex*

B. unconditioned stimulus

C. conditioned reflex

D. conditioned response

92%, .26. This was purely definitional: unconditioned responses are reflexes -- innate responses to certain stimuli -- the unconditioned stimulus. The conditioned response is not really a reflex; it's an acquired (learned) response to a previously neutral stimulus that, in some ways, may resemble an unconditioned reflex.

28. Which of the following phenomena demonstrates conclusively that an extinguished CR is not forgotten?

A. Higher-order conditioning

B. Savings in relearning

C. Spontaneous recovery

D. Both b and c*

84%, .30. In higher-order conditioning, a conditioned response transfers to a new conditioned stimulus, CS2, that is paired with the original conditioned stimulus, CS1. It doesn't have anything much to do with extinction. Spontaneous recovery of an extinguished response after an interval of rest, and savings in relearning a CR following the reinstatement of reinforcement, both indicate that the extinguished response remains in the organism's behavioral repertoire; it's not lost, or forgotten, but is simply being suppressed or inhibiited.

29. Which of the following statements is false?

A. Initially, discrimination training results in generalization.

B. In discrimination learning, the CS+ takes on significance opposite of the CS�.

C. The CS� takes on the role of the inhibitor.

D. While the CS+ predicts the occurrence of the US, the CS� conveys little or no information.*

45%, .30. When an organism receives training with a CS+ (which is paired with the US) and a CS- (which is not), it will initially respond to both stimuli, as a result of generalization. However, with further experience that organism will learn to distinguish between the two stimuli -- that the CS+ predicts the US and the CS- predicts its absence. Therefore, while the CS+ will elicit the CR, the CS- will inhibit it. Note, however, that it is not the case that the CS- conveys little or no information. The CS- conveys the information that the US will not occur -- which is information of a negative sort.

30. Instrumental conditioning differs from classical conditioning in which of the following ways?

A. Reinforcement is contingent upon a response in instrumental conditioning but not in classical conditioning.*

B. Instrumental conditioning requires "insight" but classical conditioning does not.

C. Classical, but not instrumental, conditioning is impossible with autonomic responses.

D. Instrumental conditioning involves stimulus-stimulus associations, while conditioning involves stimulus-response associations.

79%, .32. In traditional S-R learning theory, neither classical nor instrumental conditioning involve insight -- they're automatic; in cognitive learning theory, both involve insights of a sort -- insights about prediction (classical) and control (instrumental). Autonomic responses, such as heart rate acceleration, a common psychophysiological index of fear, are certainly subject to classical conditioning; there has been considerable debate over whether they're subject to instrumental conditioning (they probably are). It's classical conditioning that involves stimulus-stimulus associations, between the CS and the US; and it's instrumental conditioning that involves stimulus-response associations, between the CS and the CR (there's no role for the US in instrumental conditioning). What happens in instrumental conditioning is that the animal is reinforced -- rewarded or punished -- depending on what it does; while in classical conditioning, reinforcement occurs regardless of what the animal does. That's why classical fear conditioning can induce learned helplessness.

31. Thorndike proposed that learning occurs because certain responses become reinforced and therefore become more likely to occur. This idea is known as the law of _________.

A. exercise

B. effect*

C. purpose

D. contingency

75%, .37. The law of effect states that responses that are rewarded tend to be strengthened, while responses that are not rewarded tend to be weakened. The law of exercise states that stimulus-response associations are strengthened by repetition. There's no law of purpose, and no law of contingency in Thorndike's version of S-R learning theory.

32. An animal hears 100 tones and experiences 100 shocks. Shock follows the tone closely in time on 2 trials only. According to a contiguity view, what does the animal most likely learn?

A. That tone is a safety signal predicting that shock is unlikely to occur.

B. A weak tone-shock relationship

C. A contrast effect, because shock was expected but not delivered on many trials

D. Nothing, since tone is not paired with shock *

45%, .20. This was a hard question, but it passed the statistical test, so we kept it in. The way to solve these kinds of problems is to construct a 2x2 table, with the CS (present or absent) labeling rows and the US (present or absent) labeling columns. In this problem, the CS-US cell has only 2 entries in it, so tone and shock are paired only 2% of the time -- in other words, hardly at all. According to the assumption of association by contiguity, the organism should learn nothing at all, because tone is rarely contiguous with shock. There's not even a weak tone-shock relationship (Option B), because tone and shock are unpaired more often than not. Whether tone serves as a safety signal depends on how many trials tone is not quickly followed by shock -- and the problem doesn't provide that information.

33. The role of contingency in classical conditioning is best illustrated by:

A. the results of the standard conditioning paradigm.

B. the results of delayed conditioning experiments.

C. the results of simultaneous conditioning experiments.*

D. the results of trace conditioning experiments.

34%, .06. A bad item. The best answer is C, because in simultaneous conditioning the CS and the US are precisely contiguous, yet contingency is lacking -- the CS provides no information about the US. In the standard conditioning paradigm, the CS and US are both contiguous and contingent (that is, the US is contingent on the CS). In the delayed and trace conditioning paradigms, contiguity is degraded somewhat, but the US is still contingent on the CS. Conditioning occurs in both paradigms, suggesting that contingency is more important than contiguity. But in the simultaneous conditioning paradigm, the CS is precisely contiguous with the US; yet no conditioning occurs, because the CS does not predict the US. Therefore, the best illustration of the role of contingency is provided by the results of simultaneous conditioning experiments -- the result being that conditioning does not occur despite good contiguity, because there's no contingency.

34. Garcia's experiment on taste-aversion learning showed that:

A. rats could learn about shock but not about nausea.

B. rats could associate some stimuli with shock but not to nausea.*

C. the assumption of the "passive organism" is valid.

D. contraprepared associations can be learned more easily if they are reinforced by shock.

58%, .39. In these experiments, rats could associate shock with sight and sound but not taste, and they could associate nausea with taste but not sight and sound. So they could learn about both shock and nausea. The taste-aversion experiments undercut three assumptions of traditional S-R learning theory -- association by contiguity (the CSs in question are equally contiguous with the USs, but only some CS-US associations get learned; arbitrariness (you can't pair sight and sound with nausea and expect rats to learn the association); and the empty organism (you have to understand how rats evolved as nocturnal eaters, to identify food by smell and taste rather than by sight and sound, to understand what they can and cannot learn). But it doesn't have anything to say about the assumption of the passive organism -- that assumption is undercut by Kamin's blocking experiments, which reveal organisms actively trying to predict events, and Seligman's learned helplessness experiments, which reveal organisms actively trying to control them.

35. What must one show in order to demonstrate that an organism is responding on the basis of a learned concept rather than on the basis of a specific stimulus?

A. That learning transfers to a situation with perceptually different stimuli*

B. That learning persists over many trials on many consecutive days

C. That the animal can use symbols to correctly select its response

D. All of the above

68%, .43. If an organism that has been trained to respond to one kind of stimulus, and responds similarly to another kind of stimulus, one on which it has never been trained, that would indicate that the organism has gone beyond the generalization gradient. It has learned more than to respond to some specific physical stimulus and other stimuli that are physically similar to it; it has learned to respond to some abstract concept instead -- not just some physical stimulus.

36. A research subject can just discern the difference between 50 and 51 candles burning in an otherwise darkened room. According to Weber's law, how many lit candles would have to be added to 300 already-lit candles before a subject could just notice the difference in illumination?

A. One additional candle, for a total of 301 candles

B. Three additional candles, for a total of 303 candles

C. Six additional candles, for a total of 306 candles*

D. Ten additional candles, for a total of 310 candles

84%, .34. This was about Weber's Law in psychophysics, where dI / I is a constant. Thus, if 1 unit of brightness makes a difference in a 50-candle room, then 6 units (1/50 of 300) will be required to make a difference in a 300-candle room.

37. What is a proximal stimulus?

A. A tree on the edge of a field.

B. Sunlight reflecting from the tree.

C. Soundwaves generated by the wind rustling the leaves of the tree.

D. The pressure of the tree on the skin when someone touches it.*

23%, .13. A bad item. This one was a little tricky, perhaps, but the point is important. The proximal stimulus isn't the whole mass of energies that radiate from the distal stimulus in all directions: it's the subset of energies that radiate from the distal stimulus and fall on the organism's sensory surfaces.

38. _________ is the collective term for information about movement that comes from receptors in the skeletal muscles, tendons, and joints.

A. Somesthesis

B. Kinesthesis*

C. The vestibular sense

D. The gravitational sense

78%, .19. This was purely definitional: somesthesis is the sense of touch; the vestibular sense is the sense of balance (it is sometimes known as equilibrium, and is mediated by gravitational forces acting on crystals suspended in a viscous liquid). Kinesthesis is the sense of movement, from receptors that pick up the activity of muscles, tendons, and joints.

39. Compare two tones of 1,000 hertz and 500 hertz. What can we say about the movement of the basilar membrane in response to these tones?

A. The peak of the vibratory wave will be closer to the oval window for the 1,000-hertz tone than for the 500-hertz tone.*

B. The peak of the vibratory wave will be closer to the oval window for the 500-hertz tone than for the 1,000-hertz tone.

C. There will be a peak in the vibratory wave for the 500-hertz tone, but there will be no such peak for the 1,000-hertz tone, which affects the entire membrane equally.

D. There will be a peak in the vibratory wave for the 1,000-hertz tone, but there will be no such peak for the 500-hertz tone, which affects the entire membrane equally.

53%, .15. This is about the frequency and place theories of auditory pitch. Up to about 1,000 hz, auditory pitch is given by the frequency with which the basilar membrane vibrates. Above about 1,000 hertz, the basilar membrane is physically incapable of vibrating that fast, and so auditory pitch is given by the point on the basilar membrane that shows the greatest vibration - -the peak of the vibratory wave. I wasn't really expecting people to know where the vibratory peak is placed, with respect to the oval window. Rather, that the location of the peak -- there's always a point of peak vibration, in any wave -- makes a difference to the 1,000 hz tone but not to the 500 hz tone.

40. The ecological view of perception holds that:

A. All the information needed for perception is provided by the stimulus environment.*

B. Mental representations of objects are constructed through a process of transduction.

C. Unconscious inferences play an important role in visual perception.

D. Perception is influenced by expectancies and beliefs.

87%, .33. Ecology means environment, and the ecological view of perception means that all the information needed for perception is provided by the stimulus environment. In the ecological view, there is no reason for the perceiver to draw on knowledge or expectations stored in memory, or to make any inferences (conscious or unconscious) or judgments. Perception just mechanically and automatically extracts information from stimulation. Transduction doesn't have anything to do with constructing mental representations -- all it does it convert proximal stimulation into a pattern of neural impulses. The perceptual centers in the cortex take these neural impulses and create mental representations out of them.

41. According to the opponent process theory, there are three cone types whose output is recoded into a total of _________ chromatic/achromatic color qualities, which are organized into _________ opponent process pairs.

A. three; three

B. four; two

C. six; two

D. six; three*

69%, .29. In the opponent process theory there are six different receptors organized into 3 opposing pairs: black/white (sensitive to the presence or absence of light), red/green, and yellow/blue. Excitation of one element in each pair inhibits or suppresses the other element.

42. As an art class exercise, Scott has painted identical twins on opposite sides of a canvas. One twin is larger than the other, and the rest of the canvas is white. Which of the following statements is true?

A. The viewer will perceive the larger twin as closer because of relative size.*

B. The viewer will perceive the smaller twin as closer because of accommodation differences.

C. The viewer will perceive the larger twin as closer because of interposition.

D. The viewer will perceive the smaller twin as closer because of texture gradients.

89%, .34. This is about the size-distance rule and the distance cue of relative size. Especially if two objects are similar in appearance, the one that casts the larger retinal image will be perceived as closer than the other one. If there was a background to provide additional cues to size and distance, one twin might be perceived as suffering from stunted growth or something, but in the absence of such cues -- and remember, the rest of the canvas is unpainted -- size is taken as a cue for distance. Because the twins are actually at the same distance from the observer, accommodation won't help much; but even if accommodation came into play, it would create the perception that the smaller twin as actually smaller, not as closer. There is no interposition (superposition), because the two images of the twins don't overlap. And there are no texture gradients -- but again, even if there were, the relative lack of detail would create the perception that the smaller twin is further away.

43. Why, as we look from left to right, do objects in front of us not seem to move from right to left?

A. There is no relative displacement on the retina.

B. The nervous system compensates for voluntary eye movements.*

C. There is relative displacement on the retina.

D. There is no absolute displacement on the retina.

37%, .40. Relative displacement on the retina is compensated for by information about the movement of the head and eyes in the opposite direction. Here is a good example of Gibson's ecological optics: it's the entire pattern of proximal stimulation, including visual stimulation from the retinal image but also kinesthetic stimulation from the muscles in the eyes and head, that provides the information for perception.

44. In the perceptual constancies:

A. Perception of the background occurs because of constant stimulation of sensory receptors.

B. Perception varies despite constant stimulation.

C. Perceptual illusions are due to constant application of the size-distance rule.

D. Perception is constant despite varying stimulation.*

57%, .40. In the perceptual constancies, perception remains constant despite varying stimulation; in the reversible figures, perception changes despite constant stimulation. Many perceptual illusions are due to misapplication of the size-distance rule, but that would help you with Question #46, below, and doesn't have anything to do with perceptual constancy.

45. According to Gestalt psychologists, which grouping factor of perceptual organization accounts for camouflage?

A. Good continuation*

B. Proximity

C. Closure

D. Similarity

38%, .35. Camouflage is a classic example of good continuation, such that the figure blends into the background, making it hard to distinguish them. In proximity, objects are grouped based on spatiotemporal contiguity. But in camouflage, the figure can be quite distant from the ground, so long as the two blend together. In similarity, objects are grouped based on similarity of appearance. In closure, openings tend to be closed, so that the figure C may be perceived as O.

46. The Muller-Lyer (arrows-feathers) illusion probably shares the same mechanism with all of the following except:

A. The Ponzo (railroad tracks) illusion.

B. The Ames room.

C. The moon illusion.

D. The Titchener (circles) illusion.*

19%, .18. A bad item. Maybe people were confused by the names of the illusions, though I thought that phrases like "arrows-feathers" would give you a good visual image. Anyway, the Muller-Lyer illusion, Ponzo illusion, Ames room, and moon illusion all involve the misuse of depth cues to infer the size of the distal stimulus. The Titchener illusion is a classic example of contextual surround.

47. With an ordinal scale,

A. numbers are assigned arbitrarily rather than meaningfully.

B. numbers reflect differences in magnitude.*

C. the difference between a score of 2 and a score of 4 is equal to the difference between a score of 8 and a score of 10.

D. b and c.

41%, .30. In nominal (or categorical) scales, numbers are simply symbols, and don't carry any quantitative meaning, such as arbitrarily labeling two groups "1" and "2", or female subjects "0" and male subjects "1" (or, for that matter, the reverse). In ordinal scales, the numbers assigned actually reflect quantitative differences -- a score of 5 is really bigger than a score of 2, and smaller than a score of 8. Rank orders are like this. In interval scales, equal differences are equal, while in ratio scales, equal ratios are equal.

48. In the distribution 1, 2, 5, 7, 7, 9, 10, 10, 10, 12, the median is

A. 7.3.

B. 7.

C. 10.

D. 8.*

86%, .21. The mean is the arithmetic average of a distribution (7.3); the mode is the most frequent score (10); and the median is the score that divides the distribution in half (8).

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 slopes downward.

96%, .33. The correlation indicates the size and direction of the relation between two variables. In a positive correlation, increasing values of Variable A are associated with increasing values of Variable B. In a negative correlation, with A goes up B goes down. The correlation coefficient can be perfectly positive, +1.00, even if the scores for the two variables are completely different. If Variable A has scores of 1, 3, and 5, and Variable B has corresponding scores of 1, 3, and 5, it's a perfect correlation; but it's also a perfect correlation if the corresponding values of Variable B are 10, 17, and 24. Correlation is about the relationship between two variables.

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

89%, .36. The usual standard for a "significant difference" is two (2) standard deviations. So, with a mean of 105 and a standard deviation of 20, two (2) standard deviations above and below the mean encompass a range of scores from 65 to 140. Therefore, a score of 135, less than 2 standard deviations above the mean is likely to come from the parent distribution, while a score of 60, more than 2 standard deviations below the mean, is not.

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