Cognitive Modeling

Psych 808(4)
Winter 1997
MW 1-2pm, 4039 East Hall
2-4 Credits


Instructor:

Thad Polk
tpolk@umich.edu
4428E East Hall
647-6982
Office hours by appointment

Requirements:

Permission of instructor.

Readings:

The syllabus was slightly revised based on student interests at the first class meeting. The revised syllabus with associated readings is below. A coursepack based on this syllabus is currently being prepared and will eventually be available at Michigan Document Service, 1117 1/2 South University. Until then, copies of papers for the next class meeting will be handed out in class.

Grading:

Grades will be computed as follows (the assignments are described below):

75% Papers (25% participation, 25% outlines/questions, 25% leading discussion)
25% Cognitive modeling project including presentation

Students may miss up to three classes without penalty (the three lowest participation/outline/questions grades will be dropped).

Credit hours and registration:

It is possible to register for 2, 3 or 4 credit hours:

2 credits: everything except the modeling project
3 credits (the default): everything including the modeling project
4 credits: everything including a much more elaborate modeling project (to be arranged with the instructor)

The best way to learn about modeling is by doing it, so I strongly encourage students to try the project.

Because this seminar requires permission of the instructor, you need an override form to register. My understanding is that psychology graduate students can fill these out themselves, but that others will need my signature. I'll bring a stack of overrides with me to class. The overrides need to be turned in at the undergraduate psychology office (East Hall 1044).

Assignments:

1. Outlines and discussion questions. At the end of each class meeting, students will be expected to turn in a brief (1-page maximum) outline of the paper(s) assigned for that class and a list of three discussion questions based on the readings.

2. Leading discussion. Discussion leadership will rotate among members of the class. Leaders should come prepared with points to be made and issues to be raised about the assigned readings as well as questions designed to draw those points/issues out of the class.

3. Cognitive modeling project. Students will work in groups of two or three students on a small computational modeling project. Every attempt will be made to put students with little computational experience in a group with more experienced students and to put together students with similar interests. A number of example projects are listed below. Feel free to choose one of the example projects or to come up with a different project that more closely matches the interests of the group. Unless you have previous experience with computational modeling, you should either choose one of the projects below or propose to re-implement a computational model that already exists and for which you have a detailed description (or perhaps a minor variant of such a model). Keep in mind that symbolic architectures such as Soar, ACT*, and EPIC are quite difficult to learn, so unless your group is very interested in that architecture and is willing to work hard to learn it, you should plan on using Nexus (a user-friendly PDP system) or a conventional programming language such as Lisp or C.

For those working on a project for which they have little experience, I recommend developing it incrementally throughout the semester in the following small parts (including a suggested timeline). Individual groups can decide how to divide the work among the group members (e.g., letting the most computationally experienced group member work on 3.5-3.7 while the less experienced members write up the proposal and prepare the presentation). Students are allowed and encouraged to consult with the instructor and local experts about their projects throughout the term.

3.1. Initial Proposal. Should describe the proposed model and the task it addresses, specify the architecture/language to be used for implementation, and specify how the project will be broken down into manageable parts (3.3- 3.7). (~Feb 3)
3.2. Proposal Revisions. A description of revisions that address issues raised with the initial proposal (if any). (~Feb 10)
3.3. Printout of output from existing model in chosen architecture/language (~Feb 19, recommended for those with little experience, optional for others)
3.4. Printout of output from "Hello, world" style system in architecture/language (~Feb 26, recommended for those with little experience, optional for others)
3.5. Printout of output from part 1 of model (~March 17)
3.6. Printout of output from parts 1 & 2 of model (~March 31)
3.7. Printout of output from complete model (~April 14)
3.8. Presentation. A 20-30 minute in-class oral presentation describing the model, its major strengths and weaknesses, and anything else you learned about the model/underlying theory and/or architecture. (April 16,21)

Example Projects

Implement any of the following neural net models using the Nexus simulation system: the McClelland & Rumelhart (1981) interactive activation model of word reading, the Cohen et al. (1994) model of spatial attention and neglect, the Farah & McClelland (1991) model of category-specific semantic memory impairments, the Polk & Farah (1995) model of brain localization for arbitrary stimulus categories.

Use ACT-R or Soar to construct a model that solves some well-defined toy problem like multi-column subtraction, the Tower of Hanoi, monkeys and bananas, blocks world...


Syllabus

1. Jan 8: Introduction to course

2. Jan 13: Computing in Cognitive Science
Pylyshyn, Z. (1989), "Computing in cognitive science", in Posner, M. (Ed.), Foundations of cognitive science, MIT Press: Cambridge, MA, pp. 51-91.


ARCHITECTURES/APPROACHES

3. Jan 15: PDP
Lippmann, R. (1987), "An introduction to computing with neural nets", IEEE ASSP Magazine, 4:4-22.

Rumelhart, D. (1989), "The architecture of mind: A connectionist approach", in Posner, M. (Ed.), Foundations of cognitive science, MIT Press: Cambridge, MA, pp. 133-159.

(Jan 20: Martin Luther King Day, no class)

4. Jan 22: Classifier systems and genetic algorithms
Holland, J. (1995), Hidden order: How adaptation builds complexity, Addison-Wesley: Reading, MA, chapter 1.

Holland, J., Holyoak, K., Nisbett, R., and Thagard, P. (1987), Induction: Processes of inference, learning, and discovery, MIT Press: Cambridge, pp. 102-126.

5. Jan 27: Soar and Unified Theories of Cognition
Newell, A. (1992), "Unified theories of cognition and the role of Soar", in Michon, J. and Akyurek, A. (Eds.), Soar: A cognitive architecture in perspective, Kluwer Academic Publishers: Netherlands, pp. 25-79.

6. Jan 29: Soar and Unified Theories of Cognition
Cooper, R. and Shallice, T. (1995), "Soar and the case for unified theories of cognition", Cognition, 55(2):115-149.

7. Feb 3: EPIC
Meyer, D. & Kieras, D. (in press), "A computational theory of executive cognitive processes and multiple-task performance: Part 1. Basic mechanisms," Psychological Review, pp. 1-2, 19-41, 63-77, 86-88.

8. Feb 5: ACT-R and rational analysis
Anderson, J. (1996), "ACT: A simple theory of complex cognition", American Psychologist, 51(4):355-365.

Anderson, J. (1991), "The place of cognitive architecture in a rational analysis", in VanLehn, K. (Ed.), Architectures for intelligence, LEA: Hillsdale, NJ, pp. 1-24.

9. Feb 10: Symbolic vs. subsymbolic approaches
Fodor, J. and Pylyshyn, Z. (1988), "Connectionism and cognitive architecture: A critical analysis", Cognition, 28(1-2): 3-71.

10. Feb 12: Alternative views
Simon, H. (1991), "Cognitive architecture and rational analysis: Comment", in VanLehn, K. (Ed.), Architectures for intelligence, LEA: Hillsdale, pp. 25-41.

Chalmers, D. (1993), "Connectionism and compositionality: Why Fodor and Pylyshyn were wrong", Philosophical Psychology, 6(3):305-319.


DOMAINS

11.Feb 17: HCI
Olson, J. and Olson, G. (1990), "The growth of cognitive modeling in human-computer interaction since GOMS," Human-Computer Interaction, 5(1-3):221-265.

12.Feb 19: Case-based reasoning
Seifert, C. (1994), "Case-based learning: Predictive features in indexing," Machine Learning, 16:37-56.

13.Feb 24: Deductive reasoning
Polk, T. and Newell, A. (1995), "Deduction as verbal reasoning", Psychological Review, 102(3):533-566.

14.Feb 26: Skill acquisition
Anderson, J. (1987), "Skill acquisition: Compilation of weak-method problem situations," Psychological Review, 94(2):192-210

(Mar 3: Spring break, no class)

(Mar 5: Spring break, no class)

15.Mar 10: Language acquisition
Rumelhart, D. and McClelland, J. (1986), "On learning the past tenses of English verbs," in McClelland, J. and Rumelhart, D. (Eds.), Parallel Distributed Processing: Explorations in the Microstructure of Cognition. Volume 2: Psychological and Biological Models, pp. 216-271.

Prince, A. and Pinker, S. (1988), "Rules and connections in human language," Trends in Neuroscience, 11(5):195-202.

16.Mar 12: Semantic memory
Farah, M. and McClelland, J. (1991), "A computational model of semantic memory impairment: Modality specificity and emergent category specificity," Journal of Experimental Psychology: General, 120(4):339-357.

17.Mar 17: Categorization
Krushke, J. (1992), "An exemplar-based connectionist model of category learning," Psychological Review, 99(1):22-44.

18.Mar 19: Attention
Cohen, J., Dunbar, K., and McClelland, J. (1990), "On the control of automatic processes: A parallel distributed processing account of the Stroop effect," Psychological Review, 97(3):332-361.

Cohen, J., Romero, R., Servan-Schreiber, D., and Farah, M. (1994), "Mechanisms of spatial attention: The relation of macrostructure to microstructure in parietal neglect," Journal of Cognitive Neuroscience, 6(4):377-387.

(Mar 24: Away at Cognitive Neuroscience conference, no class)

19.Mar 26: Working Memory
Zipser, D. (1991), "Recurrent network model of the neural mechanism of short-term active memory," Neural Computation, 3:179-193.

Burgess, N. and Hitch, G. (1992), "Toward a network model of the articulatory loop," Journal of Memory and Language, 31(4):429-460.

20.Mar 31: Explicit learning&memory
McClelland, J., McNaughton, B. and O'Reilly, R. (1995), "Why there are complementary learning systems in the hippocampus and neocortex: Insights from the successes and failures of connectionist models of learning and memory," Psychological Review, 102(3):419-437.

21.Apr 2: Vision
Hildreth, E. and Ullman, S. (1989), "The computational study of vision," in Posner, M. (Ed.), Foundations of Cognitive Science, MIT Press: Cambridge, MA, pp. 581-630.

22.Apr 7: Visual word recognition
Plaut, D., McClelland, J., Seidenberg, M. and Patterson, K. (1996), "Understanding normal and impaired word reading: Computational principles in quasi-regular domains," Psychological Review, 103(1):56-115.

23.Apr 9: Neural organization
Zhang, J. (1991), "Dynamics and formation of self-organizing maps," Neural Computation, 3(1):54-66.

Polk, T. and Farah, M. (1995), "Brain localization for arbitrary stimulus categories: A simple account based on Hebbian learning," Proceedings of the National Academy of Sciences, USA, 92:12370-12373.

Miller, K., Keller, J., and Stryker, M. (1989), "Ocular column dominance development: Analysis and simulation," Science, 245:605-615.


FINAL DISCUSSION AND PRESENTATIONS

24.Apr 14: Discussion: Is modeling worthwhile? Why? When? How/what approach?

25.Apr 16: Presentations

26.Apr 21: Presentations