Spring 2003 Final Exam

University of California, Berkeley

Department of Psychology


Psychology 129 / Cognitive Science 102

Scientific Approaches to Consciousness

Spring 2003


Final Examination



Part 1

Answer one (1) question in each of five (5) of the following six (6) sections. Each question is worth 10 points, so that this part of the exam is worth a total of 50 points. The front of each page should provide more than ample room for your answer Ė after all, youíve only got about 10 minutes to think and write! -- but the reverse of each page has been left blank for your convenience, should you decide to lapse rhapsodic.

Remember, though, to leave one page, both sides, entirely blank Ė because in this part of the exam, you are only answering 5 out of 6 questions!

Do not provide long-winded answers. You have only 10 minutes, on average, for each question, and we are grading accordingly. You should only need one side of the paper, but we give you another page for each question in case you need or want it. Use this additional space sparingly.

Write legibly, or we wonít be able to appreciate how wonderful your answers are.

Circle the letter (A or B) corresponding the option within each set that you are answering

Be sure to provide your name and student ID# on each page, including this one.

Also, please indicate your Discussion Section # (or time, or GSI) here:_____________



Question 1. Choose one:

A.  What is the difference between explicit and implicit memory? (2 points) How do we know that they are really different? (3 points) How do implicit expressions of memory observed in amnesic patients differ from those observed in neurologically intact subjects? (2 points) How might the concept of implicit memory be extended to other domains, such as perception, learning, thinking, emotion, or motivation? (Pick one, 3 points)

Explicit memory refers to conscious recollection of some past event, as exemplified by standard tests of recall and recognition. Implicit memory refers to any change in the subjectís experience, thought, or action that is attributable to a past event, as exemplified by priming effects.

We know that explicit and implicit memory can be dissociated, in at least two senses. First, amnesic patients can show implicit memory in the absence of explicit memory. Second, experimental variables such as depth of processing at the time of encoding, which have major effects on explicit memory, have little or no impact on implicit memory.

Implicit expressions of memory in intact subjects differ from those observed in brain-damaged subjects in that the intact subjects do have explicit memory for at least some of the studied material. Because intact subjects show priming regardless of whether they recall or recognize the items, we can say that implicit memory is independent of explicit memory.

We can define implicit perception as any change in the subjectís experience, thought, or action that is attributable to an event in the current environment, in the absence of (or independent of) conscious perception of that event. "Subliminal" perception and "blindsight" are examples.

We can define implicit learning as any change in the subjectís experience, thought, or action that is attributable to a learning experience, in the absence of (or independent of) conscious awareness of either the learning experience or what has been learned. (We didnít discuss implicit learning, but if you know the definition of learning, you can apply the implicit-explicit distinction by analogy.)

We can define implicit thought as any change in the subjectís experience, thought, or action that is attributable to a mental state, such as an idea or an image, that is neither a percept (representation of a current event) nor a memory (representation of a past event). An example might be "intuition" effects in problem solving.

We can define implicit emotion as any change in the subjectís experience, thought, or action that is attributable to an emotional state (such as joy or anger), in the absence of (or independent of) conscious awareness of that feeling. In this case, implicit emotion would be indexed by behavioral or physiological changes that accompany conscious feelings. Implicit emotion should be distinguished from alterations in conscious emotion that reflect implicit perception or memory, as in the case of the "subliminal" mere exposure effect.

We can define implicit motivation as any change in the subjectís experience, thought, or action that is attributable to a motivational state (such as hunger or achievement motivation), in the absence of (or independent of) conscious awareness of that state. We didnít discuss implicit motivation in class, but if you understand the concept of motivation, you can apply the explicit-implicit distinction to it.



B. What are the functional specializations associated with the two cerebral hemispheres? (3 points) What is the evidence for dual consciousness in the hemispheres? (3 points) Is the right hemisphere unconscious? If so, in what way? If not, why not? (4 points)

Studies of patients with cerebral commissurotomy, in which the bundle of nerves joining the two cerebral hemispheres has been severed, show that each hemisphere is specialized for different kinds of cognitive tasks. In general, for example, the left hemisphere is specialized for language and verbal processing, while the right hemisphere is specialized for visuospatial processing. It has also been suggested that the left hemisphere is particularly good at "rational, analytic" processing, while the left hemisphere is particularly good at "intuitive, holistic" processing.

By virtue of contralateral projection, the right hemisphere receives input from the left side of the body (or, in the case of vision, the left half-field of each eye), and vice-versa for the left hemisphere; and the right hemisphere controls the actions of the right arm and leg, and vice-versa for the left hemisphere. Thus, when the two hemispheres are disconnected, the right hemisphere will not know what the left hemisphere is doing, and vice-versa. On the assumption that both hemispheres have the capacity for conscious awareness, this sets up a situation of dual consciousness, although only the left hemisphere can express the contents of consciousness verbally. The situation is illustrated by experiments that control which hemisphere receives sensory input, and which hemisphere makes the response. This is essentially the position of Roger Sperry.

However, Michael Gazzaniga has suggested that the right hemisphere isnít conscious at all. He appears to identify consciousness with language capacity (thus effectively denying consciousness to individuals, and species, which lack language). Also, he appears to identify consciousness with the capacity to perform complex cognitive activities. In Gazzanigaís view, the right hemisphere may be capable of processing inputs and outputs, but only the left hemisphere is capable of interpreting what is going on, and integrating this activity with an ongoing narrative. These interpretive and integrative functions are critical to consciousness, in his view. On the other hand, if consciousness is first and foremost about awareness, then it seems more conservative to say that the right hemisphere might well have ongoing awareness of what it is doing, and thus conscious in that sense, even if it lacks the capacity to reflect on that awareness in various ways. The question boils down to whether you identify consciousness with awareness, or with complexity and language.



Question 2. Choose one:

A.  What is the relation between dreaming and REM versus NREM sleep? (2 points) Describe Hobsonís activation-synthesis theory of dreams, as it relates dreaming to brain physiology? (3 points) What are the implications of this theory for the meaning of dreams? (2 points) What does Foulkesís cognitive theory of dreams add to the activation-synthesis theory? (3 points)

The original finding of Aserinsky and Kleitman, subsequently confirmed by Dement and Kleitman, was that dreaming is associated with REM sleep. However, a lot depends on what you mean by "dream". If by "dream" you mean any sort of internally generated mental activity, then dreaming occurs in Stage NREM as well, as indicated by hypnagogic and hypnopompic imagery, as well as and that thoughts, images, and reveries that are often reported upon awakening from Stages 2, 3, and 4. But if by "dreams" you mean a combination of vivid, complex imagery, narrative continuity, bizarreness, and emotionality, then dreams occur far more frequently in REM than in NREM.

Hobsonís activation-synthesis theory basically states that dreams are an incidental byproduct of the activation by pontine structures located in the brainstem of certain neural networks in the cerebral cortex during REM sleep. These neural structures correspond to certain thoughts and images, which, when synthesized into a coherent package, constitute the content of the dream. Activation of the autonomic nervous system leads to emotional arousal, which is also incorporated into the dream experience. Simultaneous blocking of motor pathways prevents the person from acting on the dream content. Hobsonís theory was subsequently elaborated as the AIM model, which attributes dreaming to shifts in Activation (high vs. low), Input Source (internal vs. external), and Modulation (cholingergic vs. adrenergic).

Hobsonís theory implies that dreams are accidental byproducts of certain physiological activities. If one set of neural networks gets activated, you get one set of thoughts and images; if another gets activated, you get another set. As such, dreams have no special meaning, and donít require any symbolic interpretation.

Foulkes doesnít believe that there is any particular association between dreaming and REM, and he is inclined to give dreams more meaning than Hobson, but the two theories are somewhat compatible in other respects. Like Hobson, Foulkes believes that dreams begin with the activation of images and memories; he just doesnít think the activation is random. Moreover, Foulkes is more interested in the cognitive processes, including linguistic processes, that are used to inject coherence into the dream content. For example, he believes that the acquisition of language, as well as "Piagetian" developmental stage, play an important role in organizing dreams.



B.  What is the evidence that sleep plays a role in memory consolidation? (2 points) Why donít we remember dreams better than we do? (3 points) Is it possible to acquire new information during sleep? (2 points) What are the implications of for sleep learning of the distinction between explicit and implicit memory? (2 points)

It has been known for a long time that there is less forgetting following a period of sleep than following a comparable interval of waking. One interpretation of this effect is that sleep reduces the opportunity for retroactive interference; another is that sleep plays a special role in memory consolidation.

Given the 90-minute REM cycle, and the length of an average nightís sleep, we can infer that the average person has at least 4-5 dreams at night; but the average person can only remember about 1 dream in the morning. It has been suggested that this forgetting of dreams might be due to "Freudian" repression, or to "normal" memory processes such as salience and interference. It has also been suggested that dreams are an example of state-dependent learning. Most of the experimental evidence favors an interpretation in terms of salience and interference. For example, people remember their dreams better immediately after awakening, which suggests that dreams occur in "sort-term" memory, and must be consolidated in "long-term" memory before they are lost through decay or displacement.

Simon and Emmonsí 50-year-old summary of the research literature still holds: sleep learning is possible to the extent that the subject stays awake. Apparently, the sorts of input-gating mechanisms postulated by Hobsonís theory of sleep prevent new information from being encoded into memory.

However, almost all research on sleep-learning employs measures of explicit memory, leaving open the possibility implicit memory for events occurring during sleep. Unfortunately, the little evidence available suggests that Simon and Emmonsí conclusion applies to implicit memory as well.



Question 3. Choose one:

A.  How are the psychoactive drugs classified? (3 points) What are the differences between the minor psychedelic drugs and the major hallucinogens? (1 point) Summarize Siegel and Jarvikís theory of psychedelic hallucinations. (3 points). How does this theory relate to Hobsonís activation-synthesis theory of dreams? (3 points)

Farthing classifies the psychoactive drugs into six categories: central nervous system stimulants, CNS depressants, narcotics, major tranquilizers, antidepressants, and psychedelics.

The minor psychedelic drugs differ from the major hallucinogens in terms of pharmacology. Marijuana contains THC and a bunch of cannabinoids, which have their primary effects on subcortical brain structures like the limbic system, while LSD is a synthetic drug that appears to act on the central nervous system. Phenomenologically, marijuana does not produce hallucinations at "normal" (i.e., nontoxic) doses, but LSD and the other major hallucinogens do Ė hence, perhaps, their category label. Moreover, Tart has suggested that the major and minor psychedelics differ in terms of the degree to which their effects on consciousness are felt to be under the control of the person using them.

Siegel and Jarvik distinguished between first-stage hallucinations, involving simple forms and colors, and later-stage hallucinations, involving complex, meaningful images. S&J argued that first-stage forms are produced by direct activation of the visual cortex, while later-stage hallucinations are produced by activation of cortical memory centers as well.

It may very well be that the hallucinations produced by the ingestion of psychedelic drugs reflect the same kinds of neurochemical processes that occur naturally, and spontaneously, during sleep. For example, first-stage psychedelic hallucinations may resemble the hypnagogic imagery experienced while falling asleep, and to some extent during Stage NREM sleep, while later-stage hallucinations may resemble the complex imagery experienced during Stage REM sleep. Hobson has recently argued for strong parallels between dream hallucinations and psychedelic hallucinations at the level of neurochemistry.



B.  What are the elements of "balanced" anesthesia? (2 points) How does balanced anesthesia differ from conscious sedation? (1 point) What is the evidence for conscious and unconscious processing during general anesthesia? (2 points each) How might the distinction between general anesthesia and conscious sedation bear on the distinction between implicit memory and implicit perception? (3 points)

Balanced anesthesia consists of several elements: sedative drugs to reduce anxiety and facilitate the induction of anesthesia; an anesthetic agent to induce loss of consciousness (sometimes a different agent is used to maintain anesthesia); a muscle relaxant to calm the operative area; and an analgesic to reduce post-operative pain.

Balanced anesthesia eliminates the anesthetic agent, and the muscle relaxant, so that the patient is awake during the procedure and can respond to instructions from the physician.

Both general anesthesia and conscious sedation usually leave the patient amnesic for the procedure. However, this amnesia affects explicit memory, and may spare implicit memory. Priming effects are routinely spared in conscious sedation, while the fate of implicit memory in general anesthesia is a somewhat more complicated matter. General anesthesia may spare repetition priming under some circumstances, but there is little evidence for spared semantic priming.

Spared priming after conscious sedation constitutes evidence of implicit memory, because the patient is not unconscious Ė hence, the primes were consciously perceived to begin with. In the case of general anesthesia, studies with the isolated forearm technique confirm that the patient is truly unconscious, not just unable to respond; therefore, spared priming constitutes evidence of implicit perception.



Question 4. Choose one:

A.  In what sense(s) does hypnosis involve an alteration in consciousness? (3 points) In what way does posthypnotic amnesia entail a loss of conscious memory? (3 points) In what way does posthypnotic amnesia entail a dissociation between explicit and implicit memory? (4 points)

In hypnosis, subjects see things that arenít there, fail to see things that are there, canít remember what happened to them, and respond to posthypnotic suggestions without knowing what theyíre doing or why. Thus, hypnosis seems to involve alterations in both conscious awareness and conscious control. Itís important to remember, however, that hypnotic experiences require more than suggestion by the hypnotist; the subject must also be at least moderately hypnotizable. Not everyone can experience the alterations in consciousness characteristic of hypnosis.

Posthypnotic amnesia entails a loss of conscious recollection in at least two ways. First, subjects cannot remember things that they would remember perfectly well if they had not been given suggestions for amnesia. Second, memory for the critical material returns when the amnesia has been canceled by a pre-arranged reversibility cue. The fact that amnesia does not occur unless it has been suggested differentiates posthypnotic amnesia from state-dependent memory, and the fact that the amnesia can be reversed, and the memories recovered, marks posthypnotic amnesia as a temporary disruption of conscious retrieval.

There is considerable evidence that during amnesia, the lost memories do not lie dormant, as it were, but rather interact with the subjectís ongoing experience, thought, and action in the manner of implicit memory. Most important, priming is spared during posthypnotic amnesia. Moreover, the priming that is spared is semantic priming, not just repetition priming. Another, more subtle dissociation between explicit and implicit memory is observed in posthypnotic suggestion: typically, hypnotic subjects have no conscious recollection of having been given the suggestion (which is why their response often surprises them; but the fact that they nonetheless respond to the suggested cue shows that they have encoded and retained a memory for the suggestion, which influences their behavior outside of awareness. (There is other evidence of spared implicit memory during posthypnotic amnesia, such as savings in relearning and retroactive interference effects, but we didnít discuss them in class and neither does Farthing).



B.  In what sense(s) does hypnosis involve an alteration in consciousness? (3 points) In what way does hypnotic analgesia entail a loss of conscious memory perception? (3 points) In what way does hypnotic analgesia entail a dissociation between explicit and implicit perception? (4 points)

[Typographical error corrected during the exam.]

In hypnosis, subjects see things that arenít there, fail to see things that are there, canít remember what happened to them, and respond to posthypnotic suggestions without knowing what theyíre doing or why. Thus, hypnosis seems to involve alterations in both conscious awareness and conscious control. Itís important to remember, however, that hypnotic experiences require more than suggestion by the hypnotist; the subject must also be at least moderately hypnotizable. Not everyone can experience the alterations in consciousness characteristic of hypnosis.

Hypnotic analgesia doesnít entail a loss of conscious memory; thatís a typo that was corrected during the exam. But it does seem to entail a loss of conscious perception. Pain is a sensory-perceptual phenomenon, and when hypnotic suggestions for analgesia are successful the subject doesnít perceive the pain stimulus as painful (in extreme cases, and in the case of hypnotic anesthesia, the subject doesnít feel the stimulus at all). In a substantial proportion of the population, the degree of pain relief is such as to permit minor, and even major, surgical procedures to be performed with hypnosis as the sole analgesic agent.

Nevertheless, there are at least two reasons for thinking that the pain stimulus, and pain, continues to register at some level outside conscious awareness. For example, physiological responses to the pain stimulus are not necessarily affected by hypnotic analgesia. These physiological responses, evoked outside awareness, constitute implicit expressions of stimulus perception. Another sort of evidence comes from Hilgardís studies with the "hidden observer" procedure, which apparently permits access to the dissociated perception of pain. The reports of the hidden observer are self-reports of phenomenal awareness, and thus are not exactly evidence for implicit perception. But they do reveal an intact representation of pain normally inaccessible to conscious awareness, and thus make it reasonable to expect that priming and other techniques would reveal implicit percepts of pain in hypnotic analgesia, just as priming constitutes evidence of implicit perception in hypnotic blindness.



Question 5. Choose one:

A. In what way does daydreaming represent alteration in consciousness? (3 points) Compare and contrast the daydreaming and meditation literature with respect to the occurrence of irrelevant thoughts. (4 points) How does daydreaming differ from "sensory deprivation"? (3 points)

Daydreaming qualifies as an alteration in consciousness because daydreamers turn their attention away from events in the external world and focus awareness on internally generated thoughts, images, and the like. Daydreaming represents a shift in awareness from one stream of thought, oriented toward the external world, to another stream of thought, oriented toward internal fantasies. In Klingerís analysis, daydreaming is stimulus-independent rather than stimulus-bound; but while the prototypical daydream is involuntary (respondent) in nature, fanciful, and vivid, daydreams may also be voluntary (operant in nature), realistic, and nonvivid.

In daydreaming, we are absorbed in our thoughts, images, and fantasies. By contrast, in meditation the goal is to empty the mind of all content Ė a process that may be facilitated, somewhat paradoxically, by focusing attention and awareness on a single object, such as oneís breathing or a mantra. Both daydreaming and meditation, however, entail a lack of responsiveness to distracting stimuli Ė thatís whatís meant by stimulus-independent thought. Research by Antrobus, for example, shows that subjects are much less likely to daydream when their attention is engaged by distracting tasks. According to a theoretical model developed by Antrobus, daydreaming consumes cognitive capacity that interferes with task performance, and vice-versa. The implication of the model is that mutual interference would be reduced if the manifest task had been automatized first Ė a situation that would leave lots of cognitive capacity left over for daydreaming!

Daydreaming is stimulus-independent thought, but in sensory deprivation (also known as restricted environmental stimulation) there are few stimuli to be independent of! People may daydream during the initial phases of sensory deprivation, but a study by Suedfeld shows that there is no more daydreaming during SD/REST than during control conditions. During SD/REST, subjects may actually be more alert and attentive to those few stimuli that slip into the situation Ė a situation characterized as stimulus hunger. Stimulus hunger, of course, is the very opposite of daydreaming.



B. How do the "mystical" experiences associated with meditation differ from those involved in absorption or daydreaming? (3 points) What does it mean to characterize meditation as producing a "de-automatization" of thought? (2 points) What evidence is there that bears on the de-automatization hypothesis of meditation? (3 points) How do the physiological correlates of meditation, as in the literature on Transcendental Meditation and the Relaxation Response, bear on the issue of de-automatization? (2 points)

Deikman has classified mystical experiences as sensate, involving intense, perceptual, cognitive, or emotional experiences that occur spontaneously; and transcendent, involving a suspension of sensation and thought ("emptying the mind") which occurs as a result of rigorous training in some meditative discipline.

Deikman described de-automatization as involving a disruption and/or reorganization of the personís habitual way of interpreting events Ė a kind of prerequisite for experiencing events in new ways. Later, cognitive psychology embraced a concept of "automatic" processes that are inevitably evoked by particular events, run incorrigibly to completion, and whose execution consumes little or no cognitive capacity.

Although the cognitive psychologists who study automaticity have had little to say about de-automatization, the technical concept of automaticity provides a means for determining whether de-automatization has occurred. For example, meditation seems to reduce interference on the Stroop task, a classic example of automaticity. Meditation also appears to reduce the occurrence of overlearned responses, and to increase subjectsí ability to generate novel (or at least) atypical responses, on various verbal performance tasks.

Most empirical research on meditation, both in "religious" forms like Transcendental Meditation and in "secular" forms such as the Relaxation Response, focuses on physiological parameters. Although there were early indications that meditation enhanced alpha activity in the EEG, this now appears to be largely an artifact of relaxation and eye closure, and most of the physiological parameters that change in meditation reflect aspects of physical relaxation. Although some early EEG research seemed to indicate that yogis do not orient to novel stimuli, and Zen meditators donít habituate to repetitions of such stimuli, these findings have not been confirmed by subsequent research.



Question 6. Choose one:

A.  How does Darwinís theory of evolution imply psychological continuities among various species? (2 points) Briefly characterize the positions of Romanes, Lloyd Morgan, Thorndike, and Washburn with respect to the continuity of consciousness between humans and nonhuman animals (2 points each)

In Darwinís theory of evolution by natural selection, new species arise when new physical traits arise spontaneously and randomly, confer a reproductive advantage, and then are passed down to offspring. But because different species descended from common ancestors, they will share some features in common. Darwinís earliest work on evolution focused on morphological traits, but the theory implied that behavioral and mental traits might evolve as well Ė and, thus, that there would be psychological as well as physical continuities among species.

Romanes assumed psychological continuity between humans and other animals, and extended human characteristics, including consciousness, down the evolutionary line, and collected a great deal of anecdotal evidence suggesting consciousness in animals.

Lloyd Morganís canon, which states that the behavior of nonhuman animals should not be explained in terms of consciousness and reasoning if simpler explanations will suffice, implies that there might be a discontinuity between humans and other animals.

E.L. Thorndike argued instead that animal behavior could be accounted for by reflexive behaviors (including conditioned reflexes); but because he accepted the principle of psychological continuity, argued that we didnít need consciousness and reasoning to account for human behavior either!

Margaret Floy Washburn viewed the problem of the animal mind as simply a variant on the problem of other minds in general, and assumed from anatomical similarities in nervous system structure that animalsí mental states could be inferred from their behavior.



B.  Describe the four elements of the "theory of mind", according to Baron-Cohen. (1 point each) What is the evidence that nonhuman animals have any of these characteristics? (3 points) What is the evidence for the theory of mind in children with "disabilities" such as blindness, mental retardation, or autism? (3 points)

The four elements in Baron-Cohenís concept of "theory of mind" are:

an intentionality detector, by which we attribute goals and desires to actors;
an eye-direction detector, by which we detect the presence of another organismís eyes and compute the direction in which they are looking;
a shared-attention mechanism, which takes the eye-direction detector one step further, and assumes that seeing is related to knowing, and that if the subject looks where the target is looking, the subject will see what the target sees.
A theory-of-mind mechanism, by which we can infer mental states of thinking, knowing, and the like from the behavior of other people (and other organisms).

Povinelliís research suggests that chimpanzees, at least, have the eye-direction detector, because they seem to be able to follow a humanís gaze to some part of the environment. However, it suggests that they do not have a shared-attention mechanism, because they donít seem to understand that looking at something refers to the thing being looked at.

Premack and Woodruffís research on problem-solving suggested that the chimpanzee Sarah had a rudimentary theory of mind, in that she was able to understand that humans had certain goals or desires. However, Call and Tomasello, working with a nonverbal version of the "false belief" task, suggests that chimpanzees do not have a theory of mind after all.

Research on the false-belief task in normal children indicates that they acquire a theory of mind sometime between in their fourth or fifth year of age. Blind and mentally retarded children pass the false-belief task too, and at about the same age as "normal" children. However, autistic children tend not to pass the false beliefs task even when they are 9 or 10 years of age; and a subgroup of autistic children donít seem to understand the referential function of gaze either.



Part 2

This is the question previewed in your syllabus, and for which you have been preparing all semester (or at least for the last couple of weeks, while you have been reading and discussing David Lodgeís novel, ThinksÖ). It is worth 50 points, but it does not have to be 5 times as long as one of your 10-point answers in Part 1. In fact, it should be no longer than about 1000 words, which is the equivalent of four (4) double-spaced pages of 12-point type Ė and it can and should be much shorter than this. Accordingly, we have provided four blank pages (both sides of this page, and both sides of the next one) for you to write your answer Ė but we donít expect you to use all this space. In any event, you should complete your answer in approximately 60 minutes. Again, write legibly, or we wonít be able to appreciate how wonderful your answers are. SoÖ

Who is right Ė Ralph or Helen Ė and Why?

In your essay, you should summarize their respective positions on consciousness (5 points each), relating them to theoretical concepts and empirical findings that you have encountered in course readings and lectures (10 points each). Then you should pick one of these positions and defend it Ė again with reference to material encountered in course readings and lectures (20 points).


To some extent, ThinksÖ is a continuation of a discussion of the relation between the sciences and the humanities that began with C.P. Snowís The Two Cultures Ė a debate that takes on increasing interest now that the sciences, whether cognitive science or neuroscience, are increasingly inclined to take seriously the topic of consciousness, which has traditionally been ruled beyond the pale and left in the domain of the humanities. It would be nice if the students viewed ThinksÖ in that context, but many of them probably havenít read Snow (hint, hintÖ).

We can pretty clearly identify Ralph Messenger as a computational functionalist of the Dan Dennett type, who thinks that the mind is like a machine, embraces a strong view of artificial intelligence, wonders whether qualia really exist, and views consciousness as a problem to be solved, if not "the ghost in the machine". Heís definitely a materialist, who thinks that there is no mind independent of the body. Ralph thinks that reality can be known, and that empirical science is the only way to know it. His great rival, Douglas Douglass, has a quantum-physical view of consciousness a little like that of Roger Penrose.

Helen Reed might be viewed as a pretty typical "soft-headed", computer-illiterate humanities type, a novelist who takes consciousness as a given, even as a gift. But she has her scientific parallels, too. For example, we might identify her with someone like Searle, who takes consciousness seriously but has doubts (!) about reductionism; or, they may identity Helen with a "Mysterian" like McGinn, who also takes consciousness as a given but doubts that science can explain it at all.

But Iím not sure that this is true. One of the things that struck me in the novel is the pathetic way in which Ralph tries to give a third person definition of consciousness Ė consider, for example, the hash he makes of "grief". By contrast, for Helen, as a novelist, third-person descriptions of consciousness are what she does for a living Ė consider, for example, her quotation from Henry James. Helen offers a way to do what Searle wants Ė to be objective about consciousness without losing its subjectivity.

In the course of their answer, students should probably discuss Ralphís and/or Helenís point(s) of view on some of the major issues discussed in the course, which are also treated in the book, like the nature (and existence of qualia), behavioristic critiques of mind and consciousness ("the ghost in the machine"), Nagelís essay on "What Is It Like to be a Bat", and Putnamís problem of "Mary the Color Scientist" raised in a monochrome environment. If someone takes on the Prisonerís Dilemma thatís fine, though we didnít discuss it at all in class.

Or, they might consider Helenís speech, in which she links consciousness to the self, and discuss things like self-consciousness in nonhuman animals and the question of whether you can have a state of consciousness without having at the same time a sense of self (or, put another way, the question of whether all consciousness is self-consciousness).

Another approach might be to abandon the mind-body problem entirely, and approach the book through another problem of consciousness, the knowledge of other minds. There are, after all, a lot of secrets held and revealed in this book. To what extent can we know what another person is thinking, and to what extent can we infer beliefs, desires and the like from peopleís behavior.

Yet another is to consider whether it is possible to give a third-person description of consciousness. Thatís what materialists like Dennett and the Churchlands seem to want to do, and what antagonists like Searle think canít be done without losing something essential.

This page last revised 12/06/08 10:52:01 AM.