imagery ch 9

Analog code

Mental images function like real visual images; depictive representation.

Propositional code

Abstract, language-like representation of images.

Imagery debate

Analog vs. propositional: whether images are picture-like or symbolic.

Finke's 5 principles of visual imagery

1️⃣ Implicit encoding - images contain information not explicitly noticed.

2️⃣ Perceptual equivalence - similar brain processes as perception.

3️⃣ Spatial equivalence - spatial relationships preserved in imagery.

4️⃣ Transformational equivalence - same mental operations as physical rotation.

5️⃣ Structural equivalence - images are organized similarly to objects.

Mental rotation (Shepard & Metzler, 1971)

Reaction time increases with rotation angle; supports analog view.

Kosslyn (1975) imagery size study

Judgments faster for larger mental images (rabbit next to fly vs. elephant).

Paivio (1978) clock angle study

Larger differences in mental clock angles → faster response times.

Reed (1974) embedded figures

People struggle to find shapes hidden in mental images → supports propositional view.

Chambers & Reisberg (1985) ambiguous figures

Can't reinterpret mental image without redrawing; supports propositional.

Oblique effect

Easier to detect vertical/horizontal than diagonal; applies to both vision & imagery.

Image scanning

Mentally scanning longer distances takes longer time—supports analog code.

Epiphenomenal

Mental images accompany cognition but don't cause it (Pylyshyn's propositional claim).

Neuropsych evidence for imagery

Visualizing activates occipital lobe; auditory imagery activates auditory cortex.

Mental model

Internal representation of how something works or is arranged (e.g., thermostat).

Cognitive map

Mental representation of spatial environment.

Analog vs Propositional maps

Analog = like real map; Propositional = verbal description.

Thorndyke (1981)

More cities → larger judged distance; supports propositional coding.

Hirtle & Mascolo (1986)

People recall campus landmarks as closer than actual; cognitive bias.

McNamara & Diwadkar (1997)

Distances from landmark → non-landmark judged longer; shows top-down influence.

Heuristic

Mental shortcut that simplifies decisions; can cause systematic distortions.

Symmetry heuristic

People "rectangularize" maps and intersections.

Alignment heuristic

Assume geographic features line up more than they do.

Rotation heuristic

Mentally rotate tilted regions to appear horizontal or vertical.

Route map

Directions from point A to B; sequential.

Survey map

Overhead spatial layout; flexible and holistic.

Egocentric representation

First-person, self-centered perspective.

Allocentric representation

Objective, environment-centered perspective.

Analog evidence summary

Rotation, size, distance, neuroimaging studies.

Propositional evidence summary

Embedded and ambiguous figure studies.

Real-world application

Navigation apps mimic our use of route/survey maps and top-down corrections.