1. Visual Representation of Knowledge Mental Imagery

2. Historical Antecedents Sir Francis Galton

3. Questionnaire to 100 people including children, artists, scientists Asked them to describe their breakfast table in terms of images: naturalness, vividness

4. Betts (1909) QMI (Question upon Mental Imagery) Visual Auditory Cutaneous Kinaesthetic Gustatory Olfactory organic

5. "High-Imagers" vs. "Low-Imagers"

6. Mental Operations Used in Imagery

7. Mental Rotation Shepard & Metzler (1971) Rotation in 2 dimensions RT increased linearly as the degree of rotation increased

8. Rotation in 3 Dimensions

10. Same results; scanning time about 55-60 degrees/sec. Age: elderly slower than younger adults on rotation Supports a spatial analog-coding approach

11. Mental Scanning Do we scan over mental images like we would scan over visual pictures? Kosslyn et al. (1978) - "Treasure Island" study

12. Results: RT increased linearly with distance on map

13. Mental Folding Shepard & Feng (1972)

14. Results: as the number of folds required to make the judgment increased, RT increased

15. Other Characteristics of Imagery

16. Imagery and Size Kosslyn (1975) P's image rabbit next to a fly P's image rabbit next to an elephant Asked to make an RT judgment about whether a rabbit has legs

17. Imagery, Size & Eating Disorders Smeets & Kosslyn study Video was morphed in direction of fatter or thinner

18. Imagery and Shape Shepard & Chipman (1970) P's asked to make a rating judgment on how similar the visual shapes of various pairs of states are Then, P's asked to do the same with mental images of states

19. Results: judgments are very similar

20. Visual Imagery Capacity Limitations

21. Kosslyn (1975) S's imagine a square, then an object (rabbit), then asked Q, e.g. legs Square: large or small; simple or complex

22. Selective Interference Brooks (1978) P's given a block letter ("L") and image it P mentally scans it 2 types of responses: verbal or pointing (on a response sheet)

23. Theories of Mental Imagery Conceptual- Propositional Hypothesis Functional- Equivalency Hypothesis Dual-Coding Hypothesis

24. Cognitive Neuroscience Findings Farah (1995) Brain lesions, Imaging