University of California, Berkeley

Department of Psychology

 

Psychology 129 / Cognitive Science 102

Scientific Approaches to Consciousness

Spring 2013

 

Midterm Examination

Scoring Guide

 

On the initial scoring of the exam, performance was perhaps a little low, with an average score of 32.13, corresponding to 64%. Psychometric analysis yielded a pretty decent reliability (Cronbach's alpha) of .85.

Item #18 had a poor item-to-total correlation, so I eliminated that item by giving everyone a score of 3. That raised the average score to 34.21. Item #8 also had a low item-to-total r, but that was because it was so "easy", so I didn't do anything.

Some items were worth 2 points and others worth 3 points, so for purposes of statistical analysis I calculated a percentage score for each item. The average item score, computed as a percentage of the points available for that item, was 68% (SD= 16%).

In this respect, Item 15 was an outlier, in that its average score was more than 2 SDs below the average of all items. I eliminated this item, as well, by giving everyone a score of 3. In order to eliminate the impact of the item while giving due credit to those who answered it correctly, I added 3 points to everyone's score, raising the mean exam score further to 36.74.

Because answering these two "bad" items may have taken time away from answering other items, I added 5 points (Item #15 was worth 3 points, Item #18 worth 2 points) to everyone's score, truncating scores at 50. This resulted in a final mean exam score of 41.81 (SD = 7.61). (There won't be a similar fix on the final, because then you'll have three hours to complete a two-hour exam.) The median score was 44. The figure shows the distribution of scores.

 

Exams will be returned in discussion sections, the week of April 1. If you think a clerical error has been made in computing your grade, contact Prof. Kihlstrom. If you think a substantive error has been made in grading a test question, give your GSI a written paragraph detailing why your answer is better than the one given in the scoring guide.

 

 

Answer each the following 20 questions.  Each question is worth 2 or 3 points, so that the exam totals 50 points. 

Do not provide long-winded answers.  You have about 2 minutes, on average, for each question, and we are grading accordingly.  Use only the space provided for your answer.  Just one or two sentences will do – three at the most.  Get right to the point.

Read through the entire exam first.  Then go back and answer the questions you find easiest.  Then turn to the harder ones.

Write your name at the top of every page, so that the exams can be separated for grading. 

Write your answers in ink.  Answers written in pencil will not be eligible for regarding. 

And write legibly, or we won’t be able to appreciate how wonderful your answers are.  Complete sentences are always nice, but they’re not absolutely necessary. 

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

 

Section 1: Introduction. 

1. How did the cognitive revolution in psychology lay the foundation for a revived interest in consciousness?  (2 points)

Mean score = 1.41 out of 2, or 70%. Item-to-total r = .32. The cognitive revolution emphasized the role of mental states and processes in intervening between environmental stimulus and behavioral response.  In particular, the early cognitive psychology focused on problems of attention and short-term memory, which involve consciousness almost by definition.  [Lecture]

 

Part 2: Introspection

2. How did the 19th-century  psychophysicists and physiological psychologists seek to make psychology an objective science of subjective experience? (2 points)

M = 1.52;. r = .33. The psychophysicists (like Weber and Fechner) identified mathematical functions that related the objective, physical qualities of a stimulus to the subjective qualities of the sensations generated by that experience.  The physiological psychologists (like Muller and Helmholtz) attempted to relate the subjective qualities of sensory experience to the specific neural pathways that mediate sensory experience, as in the Doctrine of Specific Nerve Energies and the Doctrine of Specific Fiber Energies). [Lectures]

 

3. What was the principal contribution of the Structuralist school of psychology to the scientific analysis of consciousness?  Give an example. (2 points)

1.59; .42. By means of experimental introspection, the Structuralists attempted to identify the basic qualities of sensory experience – the elementary “building blocks” out of which complex sensory experiences are built.  So, for example:

[Students don’t have to name every quality; just examples within a single modality will suffice; most will stick with the primary colors].  [Lectures]

 

4.  How could psychology and cognitive science be a science of the mind, and still ignore consciousness? (2 points)

1.24; .38. Cognitive psychology, and cognitive science generally, differs from behaviorism in that it postulates internal mental states and processes intervening between stimulus and response.  But given the computer model of the mind, and the analogy of brain/hardware and mind/software, it is possible to describe mental life in purely functional terms, proceeding from stimulus input to response output, without every confronting consciousness or having to explain it.  [Revonsuo, Chapter 2]

 

5. Why is the relation between attention and consciousness complicated? (3 points)

2.09 out of 3, or 70%; .38. It seems natural to identify consciousness with attention, because when we pay attention to something we become conscious of it.  But this is not always the case.  When we pay attention to something, we also have some awareness of what is in the background, despite the fact that we’re not paying attention to it.  And in the phenomena of inattentional blindness, change blindness, and visual agnosia, we can be unaware of something even though we are paying close attention to the region of space in which that object is presented.  [Revonsuo, Chapters 3 and 4]

 

Part 3: Mind and Body

6. How does the “Cartesian impasse” relate to the “explanatory gap”? (2 points)

1.77, .39. The Cartesian impasse refers to the struggle to explain how mind and body, which seem (to Descartes, and most of the rest of us) so different, can interact with each other.  The explanatory gap is another metaphor for the same problem: We can have an explanation for how the brain works (which is what neuroscience does), and we can have an explanation for how the mind works (which is what psychology and cognitive science do), without being able to put those two explanations together to explain how we get conscious mental states.  [Lectures and Revonsuo Chapter 1]

 

7.  What are the implications of identity theory for the neural correlates of consciousness?  (3 points)

2.13, .56. Identity theory postulates that mental states are identical to neural states.  The “token” version of identity theory allows techniques such as brain imaging to neural correlates of conscious mental states that generalize across subjects.  But token identity theory, holds that the same mental state may be realized in different brain states, so that any findings of brain-imaging would not necessarily generalize across subjects.  [Lectures]

 

8.  Apparently, hypnotic and nonhypnotic suggestions can influence allergic reactions.  What does this tell us about mind-body relations? (3 points)

2.9, .19. This fact tells us that the relationship between mind and body goes two ways: mental states (such as the belief that one has come into contact with a poisonous plant) can influence bodily states outside the nervous system (such as the symptoms of contact dermatitis).  It’s no surprise that mental states are correlated with brain states.  The surprise is that mental states can have effects outside the nervous system.  [Lectures]

 

9.  Why is functional magnetic resonance imaging the current “technique of choice” for identifying the neural correlates of consciousness? (2 points)

1/78, .29. fMRI allows us to directly observe the brain in operation while subjects are in various mental states, performing various tasks.  Compared to PET imaging, fMRI has more fine-grained temporal resolution.  Compared to EEG and MEG, fMRI offers more precise localization of brain activity.  [Revonsuo, Chapter 7).

 

10.  What is Dennett’s objection to the “Cartesian Theatre” model of consciousness? (3 points)

1.67, .49. The “Cartesian Theatre” refers to the place in the brain where consciousness occurs, where “it all comes together”, and we can watch consciousness as if it were playing out on a theatrical stage.  Dennett denies that there is such a place in the brain, because he denies that “it all comes together”.  His “multiple drafts” model postulates that information-processing consists of a series of informational states, any one of which could become conscious at any particular moment.  [Mystery of Consciousness, Chapter 5; Revonsuo, Chapter 10].

 

11.  How does Chalmers’s theory of consciousness verge on panpsychism? (3 points)

1.72, .56. Panpsychism is the view that consciousness permeates the universe, as a property of any causal system that represents informational states.  Because physical systems such as thermostats are causal systems that represent informational states, Chalmers’s position forces us to say that they have conscious experiences: there’s “something it’s like” to be a thermostat.  Not very interesting experiences, perhaps, because thermostats don’t represent very much information, but experiences nonetheless.  [Mystery of Consciousness, Chapter 6; Revonsuo Chapter 10].

 

Part 4: Attention and Automaticity

12.  What are the implications of masked priming effects for the debate over early vs. late selection in attention? (2 points)

1.35, .52. Masked priming, an index of “subliminal” perception, includes semantic priming, not just repetition priming.  Therefore, some meaning analysis must be possible before attention is directed to the object.  Therefore, early-selection theories of attention, which hold that attention is required for semantic analysis, must be false.  [Lectures].

 

13.  “Mental life is 99.44% determined by automatic processes”: Respond briefly.  (3 points)

1.84, .59. This claim has not been demonstrated empirically.  Our best guess is that task performance is determined by a mix of automatic and controlled processes.  Evidence from the process dissociation procedure and similar paradigms indicates that automatic processes only dominate in limited circumstances which preclude conscious processing.  [Lectures]

 

14.  Why does the Libet experiment appear to compromise our sense of free will? (2 points)

1.49, .58. Free will begins with our experience of consciously choosing what to do and when to act.  But the Libet experiment on the “readiness potential” seems to show that we are preparing to act before we’re aware of our intention to act.  Free will is about conscious choices, and the Libet experiment seems to suggest that our choices are made unconsciously.  [Lectures]

 

15.  What are the implications of Damasio’s “anti-Cartesian” theory for identifying the neural correlates of consciousness? (3 points)

0.72, .44, a bad item. Damasio argues that consciousness can only occur in a being that has an internal representation of itself.  Therefore, we would need to identify three neural correlates: the neural patterns that create images of the objects of consciousness; the neural patterns that create images of the organism itself; and the neural patterns that relate the two other patterns.  [Revonsuo Chapter 11]

 

Part 5: The Explicit and the Implicit

16.   When does priming provide evidence of unconscious memory? (2 points)

1.45, .48. Nobody should be surprised to find that priming effects accompany conscious recollection.  Priming indicates unconscious memory when (1) the prime has been presented in the past (i.e., after at least 30 seconds of distraction); (2) the priming effect occurs in the absence of, or at least independently of, conscious recollection; (3) the test of explicit (conscious) memory has to be matched with the test of implicit (unconscious) memory in terms of the cues provided to the subject.  [Lecture]

 

17.  Why should demonstrations of subliminal perception pose no threat to those who are worried about unconscious advertising and other nefarious effects?  (3 points)

1.88, .57. Masked priming and other forms of subliminal perception are limited in at least two ways (any two will do).  (1) Masked priming effects don’t last too long (on the order of seconds).  (2) Semantic priming appears to occur for single-word primes, but not for multiple-word primes.  (3) There’s actually no empirical evidence that things like “subliminal suggestion tapes” actually work.  (4) In some instances, there are no suggestions on so-called subliminal suggestion tapes. 

 

18.  How does implicit learning differ from implicit memory? (2 points)

1.20, .24, a bad item. Implicit memory refers to episodic memory, or memory for specific events.  Implicit learning refers to semantic and procedural knowledge acquired through experience. 

 

19.  Studies with the Implicit Association Test appear to show that even “unprejudiced” white subjects unconsciously harbor activate negative stereotypes and attitudes toward African-Americans.  What are two problems with this conclusion?  (3 points)

1.76, .40. Where to begin?  Any two of the following will do. 

 

20. How do blindsight and visual object agnosia expand our understanding of visual consciousness?  (3 points)

1.63, .37. In blindsight, patients can describe objects that they cannot see, suggesting the existence of unconscious visual percepts.  In visual object agnosia, they can interact appropriately with objects that they cannot describe or identify, suggesting the existence of unconsciously guided action.  Accordingly, there must be separate neural systems supporting visual awareness and visually guided behavior, such that the latter can proceed outside of conscious awareness of the object of perception.  [Revonsuo Chapter 5]

 

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 20.

Exams will be returned in sections after Spring Break.

 

This page last revised 03/24/2013 6:01 AM.