Psy 416: Reasoning and Problem Solving Fall 1998

Chapter 7: Mental Chronometry

 This chapter presents a series of studies on different types of problems where the primary focus is on how long different processes take. Implicit in the studies is the belief that the mind is basically a computational device, and computations take time. If we can figure out how much time different tasks take, perhaps we can get some insights into the algorithms used by the problem solver to solve the problems. In addition creative experimentation gives (tentative) answers to how some of these algorithms may be implemented. We might answer the question "What are the mechanisms that compute the algorithms?"

The two primary methods of measuring how long processes take are Reaction Time experiments and Tachistoscopic exposure time experiments. By measuring how long it takes to do different tasks, or by measuring how good performance is for different tasks after a limited amount of time to work on it, a researcher can generate theories about what underlying processes are involved. A large amount of cognitive research uses variants of these methods.

Donders and the subtractive method

  1. Simple RT                  RT=to
  2. Go--no go RT            RT= to+a           a=stimulus identification time
  3. choice RT                  RT= to+a+b       b=response selection time
Other reaction time studies
  1. Posner and physical and name matching
  2. Sternberg and memory sampling,
  3. Shepard and mental rotation

    4. (Mayer's view of rotation as steps vs. a rotation)
    Pylyshyn's criticism of rotation, argument for underlying propositional format
  4. Gough and sentence verification, parsing a sentence to obtain its meaning
  5. Clark and Chase and sentence verification, propositions and comparative equivalence operations
  6. Greenspan and Segal and sentence evaluation
  7. Lawson and sentence evaluation: using analogical representations
  8. Tanenhaus and sentence evaluation: measuring eye movements and interaction between linguistic and perceptual phenomena
  9. Olson & Filby, actives, passives and focus
The view of mental chronometry is that by studying differences in performance under different conditions you can find out quite a bit about what the mental processes are in different complex cognitive acts.

The models are conceptually compatible with the general information processing models and thus with computational models. One can simulate these processes. Such modeling is one of the major pastimes of many AI researchers.

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