Spring 2005 Midterm Exam


University of California, Berkeley

Department of Psychology


Psychology 129 / Cognitive Science 102

Scientific Approaches to Consciousness

Spring 2005


Midterm Examination


Scoring Guide and Feedback



From my point of view, the exam went pretty well -- especially given that it was an experiment with a new format.  And from my point of view, the experiment was pretty successful, in terms of producing more-or-less objective questions that can be quickly and reliably graded, and I intend to use it again in the future.

On the initial scoring of the exam, the mean score was 35.9, or a little less than 72%.  That's OK, but it's a little low for an advanced, specialized course intended for majors.  However, after a couple of adjustments, the mean score rose to 44.2, or a little more than 88% (median score = 44.7).  That's right where it should be. 

Here's how the scoring was adjusted.

In Part A, the intention was that the mean score on each of the 12 items would be the same, somewhere between 3 and 4 points.  And, in fact, the mean score on those 12 items was 3.3.  However, Items #7 and 8 yielded means that were lower than the desired range (they were also the items least frequently attempted in the first place): 2.9 and 3.0, respectively.  Accordingly, we added 0.4 points to Item #7 and 0.3 points to Item #8, to bring their means up to 3.3.  

So, when you get your exam back, if you attempted either Item #7 or #8 or both, add 0.4 and 0.3 points to your total score, respectively.

In Part B, the first thing you had to do was name some names.  This was, frankly, an experiment.  I know I told you that you didn't have to memorize the names and other details of specific experiments, and you didn't.  But if I said "Dogs and meat powder" you ought to think of Pavlov, and if I said "transformational grammar" you ought to think of Chomsky.  Even more so with philosophical work, in which ideas are even more closely identified with their authors.  So, if you read "How do I get rid of qualia?  Just watch!", you ought to immediately think of Daniel Dennett.  Anyway, there was no way I could warn you about this type of item without evoking in at least some of you an incredibly unproductive  effort to memorize the entire contents of Searle's book (from which most of the quotations were drawn).  So, in a compromise, I decided to surprise you with the question, but also to not count your responses -- this time.  Be warned, however, that I now feel perfectly free to include such an item in future exams. In fact, to discourage memorization, I might even include quotations from other works by the authors in question, which students haven't read, to see whether they can identify the source based on what they did read.

In any event, everyone received a full 8 credits for the "name-naming" segment of Part B.  

In the more substantive segment of Part B, the intention was again that the mean score on each of the items would be the same, somewhere between 3 and 4 points (plus the free points to bring the exam total up to 50).  This worked out pretty well, with a mean score on these 8 items of 4.3 -- except for Item #13 (which, again, was attempted only very infrequently).  Accordingly, we added 0.3 points to that item, to bring its mean up to the group average of 4.3.  

So, if you attempted this item, add 0.3 points to your total score.


Part A is worth a total of 32 points. Part B is worth a total of 18 points, for an exam total of 50 points.

Do not provide long-winded answers. You have less than 5 minutes, on average, for each question, and we are grading accordingly. Use only the space provided for your answer. If you need more space, use the other side of the page.

Write legibly, or we won’t be able to appreciate how wonderful your answers are.

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


Part A. Answer 8 of the following 12 questions. Each question is worth 4 points, so don’t write much. Each of the questions can be addressed satisfactorily in a short paragraph of four or five sentences. There is no bonus for answering all 12 questions, so don’t do it.

Note to GSIs: Give 1 point if the student writes anything at all, 2 points for a minimally responsive answer. The typical paragraph will get 3 or 4 points.


1. How does the philosopher Owen Flanagan distinguish between "conscious inessentialism" and the "epiphenomenalist suspicion"?

Conscious inessentialism is the idea that consciousness is not required for many information-processing functions, such as learning. However, conscious inessentialism assumes – or at least is open to the idea – that consciousness is essential for some functions. Epiphenomenalism is the idea that consciousness plays no causal role at all in behavior. Not only is it not necessary for some forms of cognition and behavior, it plays no role in any of them.  Mean score = 3.3.  


2. How does the philosopher David Chalmers distinguish between the "easy" and the "hard" problems of consciousness?

Easy problems are those that are susceptible to the standard methods of science, such as the processes involved in attention. They are mostly "how" questions of mechanism. The hard problems are more like "why" questions –in particular, why does consciousness occur at all? Of course, translated into the question of the neural correlates of consciousness, this "why question becomes a "how" question – namely, "How do brain processes generate conscious experience?". But even so, this question seems different, at least to Chalmers, than questions like "How is visual input processed through the brain?".  Mean = 3.6.


3. What are qualia?

Qualia are the subjective qualities of conscious experience – in Nagel’s terms "What it is like" to see red, or taste sweet, or feel anger. By definition, qualia are ineffable (cannot be described), intrinsic to the experience (belonging to one experience but not another), private (subjective), and immediate (not derived from other qualities).  Mean = 3.4.  


4. How does the functionalist analysis of consciousness bear on the problem of (philosophical) zombies?

Functionalism analyzes consciousness in terms of the functions it performs, instead of the states (such as qualia) it produces. In a functionalist analysis, consciousness takes certain inputs (like damage to a body part) and generates certain outputs (like crying) from them. Any system that performs the same functions has the same states. If zombies are defined as creatures who can do everything that humans can do, but who lack consciousness, then zombies are impossible: any such creature would have consciousness, like humans do.  Mean = 3.2.


5.  What is the problem of the homunculus?

The homunculus is "the little man in the head", or perhaps the self, which observes, with its inner eyes and ears, etc., the sensations being played out in the Cartesian theatre (or, perhaps, the Cartesian movie screen), thus giving rise to conscious experiences. The first problem is where the homunculus and the theatre might be located. The second and more important problem is infinite regress: the homunculus itself must have its own set of inner sensory receptors, and a brain containing its own homunculus; and that homunculus also must have its own set of inner sensory receptors, and a brain containing its own homunculus. And so on….  Mean = 3.4.


6.  According to Muller's doctrine of specific nerve energies, what is the source of qualia?

According to the doctrine of specific nerve energies, each modality of sensation, and every quality within each sensory modality, is determined by the neural system that processes sensory information. Thus, the quality of "hearing" rather than "seeing", is not determined by mechanical vibrations and electromagnetic waves, but rather by the temporal and occipital lobes; and the quality of seeing "red" rather than "blue" is not determined by the wavelength of light, but rather by the activity of specific neural systems (in this case, organized by opponent processes) that give rise to these sensations.  Mean = 3.4.


7.  In the context of visual attention, what is the significance of "pop-out"?

"Pop-out" occurs when subjects search a visual array for a particular target. When the target shares many features with the other elements of the array, search consumes considerable cognitive resources. But when the target is highly distinctive, sharing few if any features with the other elements, it is identified easily, quickly, and effortlessly -- it just "pops out". The phenomenon indicates that attention can be "captured", automatically, in the absence of conscious effort; while some attentional processes are consciously controlled, others occur automatically.  Mean = 2.9.  This was something discussed in the text only, and not in class.  After adjustment, mean = 3.4.


8.  What are the features of an automatic process?

Automatic processes are inevitably evoked by appropriate stimulus conditions; once invoked, they are executed incorrigibly, and cannot be stopped; they consume no attentional resources; the do not interfere with other, attention-consuming, cognitive activities. Taken together, we may say that they are unconscious in the strict sense of the term, proceeding outside conscious awareness and independent of conscious control.  Mean = 3.0, which was a little lower than intended.  After adjustment, mean = 3.3.


9.  What is the evidence that implicit memory is unconscious memory?

Amnesic patients show priming and similar effects of prior experience, even though they cannot recall or recognize the priming experience itself. Such population dissociations indicate that implicit memory is preserved in the absence of explicit memory. In normal subjects, performance on priming tasks is unaffected by experimental manipulations, such as level (or depth) of processing, which are important determinants of recall and recognition. Such functional (or experimental) dissociations indicate that implicit memory is independent of explicit memory.  Mean = 3.2.



10.  What is visual neglect and how is it relevant to unconscious perception?

Visual neglect, also called hemifield neglect or unilateral neglect, is a neurological syndrome in which patients who have suffered strokes (usually damaging the right hemisphere) are inattentive to visual stimuli in one visual half-field (usually the left). When asked to bisect a horizontal line, they usually put their mark about one-quarter the way in from the right end. It's as if they don't realize that the left half of the line is there. However, information on the unattended left side of the object can often influence choice behavior, as in the experiment with the house on fire. This effect on choice indicates that the left side has been processed, even though the patient has not consciously attended to it.  Mean = 3.2.



11.  What is our best guess as to how anesthetics operate to eliminate consciousness?

Different anesthetic agents may have different mechanisms. According to one theory, anesthetics either alter membrane dynamics to inhibit action potentials (perhaps by expanding the cell membrane), or interfere with synaptic transmission (by binding to proteins that play a role in the "lock and key" mechanism). According to another theory, anesthetics inhibit excitatory neurotransmitters by acting on NMDA receptors, or activate inhibitory neurotransmitters by acting on GABA receptors. [A good answer need not spell out all the alternatives, but should have a "dual-process" flavor.]  Mean = 3.1.  


12. What is the difference between coma and the persistent vegetative state?

Coma is a chronic loss of consciousness, in which the eyes are closed and the normal sleep-wake cycle is abolished, though vegetative functions are preserved. The patient does not communicate, and is not responsive to environmental stimulation. The persistent vegetative state has been characterized as "wakefulness without consciousness", because the person’s eyes will open sleep-wake cycle is restored. However, response to the environment is minimal: consisting mostly of auditory and visual startle reflexes, and reflexive crying and smiling.  Mean = 3.8.  



Part B. Identify the authors of each of the following 8 quotations (1 points each). Then, for 10 points, write short paragraphs explicating 2 of these quotes (5 points each). As in Part A, just a couple of sentences will do nicely. There is no bonus for explicating more than two quotes, so don’t do it. If you cannot identify the author of a quote, you may still explicate it.

Note to GSIs: 1 point for each correct identification. For each of the two paragraphs, give 1 point for free (to bring the exam up to 5 points), and then grade on the usual 0-4 point scale. The typical paragraph will get 4 or 5 points (including the free point).


13. "The ghost in the machine"

Gilbert Ryle: This is the classic statement of philosophical behaviorism, forerunner to contemporary functionalism, and it identifies consciousness with behavior.  Mean = 4.0.  This was from Blackmore, but I also think I mentioned it in lecture.  In any event, the average was a little low.  After adjustment, mean = 4.3.


14. "Consciousness is what makes the mind-body problem really intractable. Without consciousness, the mind-body problem would be much less interesting. With consciousness, it seems hopeless."

Thomas Nagel: This can be interpreted as mysterianism, but the real point is that it’s easy to build an information-processing machine, but a lot harder to build one that has consciousness.  Mean = 4.1.


15. "’You,’, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules."

Francis Crick: This is the statement of his "astonishing hypothesis", which is nothing more than down-home materialism; perhaps what makes it astonishing is that most people, deep in their heart of hearts, are dualists.  Mean = 4.2.  


16. "On the view that I am tentatively putting forward, consciousness would be some manifestation of this quantum-entangled internal cytoskeletal state and of its involvement in the interplay... between quantum and classical levels of activity."

Roger Penrose: He is invoking one mystery, quantum theory, to explain another – consciousness.  Mean = 4.6.


17. "Even if mental events are not among the data of science, this does not mean we cannot study them scientifically.... The challenge is to construct a theory of mental events, using the data that scientific method permits. Such a theory will have to be constructed from the third-person point of view, since all science is constructed from that perspective."

Daniel Dennett: This is a contemporary version of Ryle’s philosophical behaviorism. Experience is private, and so it cannot be scientifically studied. The science of consciousness is going to have to be a science of public behavior.  Mean = 4.8.  


18. "Whether the organization is realized in silicon chips, in the population of China, or in beer cans and ping-pong balls does not matter. As long as the functional organization is right, conscious experience will be determined."

David Chalmers: In his dual-aspect theory of consciousness, Chalmers seeks to adopt a materialist stance while continuing to take consciousness seriously.


19. "’The problem of consciousness’ is the problem of explaining exactly how neurobiological processes in the brain cause our subjective states of awareness or sentience; how exactly these states are realized in the brain structures; and how exactly consciousness functions in the overall economy of the brain and therefore how it functions in our lives generally."

John Searle: Here Searle insists that consciousness cannot be studied by leaving out its subjective, first-person aspect; and also that consciousness has causal powers, and is not merely epiphenomenal.  Mean = 4.1.  


20. "Just as the stomach is an organ designed to produce digestion, so the brain is an organ designed to produce thought"

Trick question. The actual quote comes from Pierre Jean Geroge Cabanis, an 18th-century French philosopher, and is a classic statement of materialist monism. But John Searle has written much the same thing, and he denies that he’s a materialist. For him, the statement is an expression of biological naturalism. Either answer gets full credit.  Mean = 4.6.  The Cabanis quote might have gone by a little fast in lecture; but again, you didn't have to know the source to be able to explicate it.



The scoring guide used to grade the exam

will be posted to the course website as soon as possible after the exam.


Exam grades will be posted on the course website

as soon as possible after March 21.


Exams will be returned in sections March 28-29.