Dissociations Between Imagery and Perception

Question 1

Guariglia et al

Answer 1

Patient with unilateral neglect, but only with images
Perception ok

Question 2

Farah et al’s patient R.M.

Answer 2

Damage to occipital and parietal lobes
Could recognize and draw objects presented to him, but couldn’t draw from memory (which requires imagery)

Question 3

Behrmann et al’s patient C.K.

Answer 3

Visual agnosia
Couldn’t visually recognize real objects but could image/draw

Question 4

Behrmann’s suggested solution

Answer 4

Visual perception is mainly a bottom-up process, starts in the visual cortex
Located at lower and higher centers
Imagery is a top-down process, located at higher centers only

Question 5

Chalmers and Resiberg

Answer 5

Participants created mental images of ambiguous figures
Harder to “flip” imaged vs. perceived ambiguous figures

Question 6

Conclusion

Answer 6

Visual perception is not effortful whereas imagery requires effort