Scanning and rotation evidence is problematic
Kosslyn's experimental results may be invalid as: 1) subjects' tacit knowledge of real objects makes them think they are supposed to work with images in the same way they work with real objects, and 2) The experimenter is able to affect the results.
Kosslyn's experimental results may be invalid as:
- Subjects' tacit knowledge of real objects makes them think that they are supposed to work with images in the same way that they work with real objects. As a result, subjects are not literally scanning or rotating images, but are mentally simulating a real scanning or rotation of a real object. That is, the task demands of the experiment confound its results.
- The experimenter is able to affect the subject with "non-verbal cues, tacit messages... loaded answers to questions and so on" (p.544). This gives rise to a variety of undesirable experimenter affects.
Charles L. Richman, David B. Mitchell, and J. Steven Reznick (1979)—as articulated by Zenon Pylyshyn (1981).