Individual Differences in Spatial Perception and Cognition:

Mary Hegarty

University of California, Santa Barbara

Structural geology, as I understand it..

• Identifying patterns in noisy data• Constructing 3-d “mental models” from 2-d

displays• Imagining internal structure e.g., a slice

through a 3-d structure• Imagining geological processes in three

dimensions• Inferring process from structure

The Problem..

• Students differ in their ability to “think spatially” that is..– Imagine three dimensional structures– Mentally manipulate spatial representations– Infer dynamic processes from static structures

• This limits their ability to learn structural geology

Outline of My Presentation

• Individual differences in spatial abilities

• Possible causal factors

• Training of spatial abilities

• Focus on cross sections problem

• Conclusions

Individual Differences in Spatial Abilities

History of Measurement of Spatial Abilities

• Practical goal: Personnel selection

• Concrete manipulation to abstract spatial abilities

• Debates about the structure of intelligence: one intelligence or many?

• Factor analysis

One Spatial Ability or Many?

• A recent meta analysis (Carroll, 1993)

- Perceptual Speed

- Spatial Relations

- Spatial Visualization

- Closure Speed

- Flexibility of Closure

Perceptual Speed

Closure Speed Flexibility of Closure

Spatial Relations (Speeded Rotation)

Spatial Visualization

Competencies Underlying Spatial Abilities

• Speed of Processing

• Working Memory

• Strategies

Speeded Rotation

Angle of Rotation

ResponseTime

High Ability

Low Ability

Demographics and Causal Factors

Causal Factors

Classic Debate:

• Nature: Evolution, heredity, hormones

• Nurture: Experience, training, education

Where this has played out:

• Sex differences in spatial abilities

• Linn & Peterson (N =172 studies)

Males’ score – Females’ score-------------------------------------

Pooled Standard Deviation

– Spatial perception .44*– Speeded rotation .73*– Spatial visualization .13 n.s.

Sex Differences in Some but not All Spatial Abilities

More Recent Meta Analysis (N = 286)(Voyer, Voyer & Bryden, 1995)

Card Rotations (.31)

3-D Mental Rotations (.67)

Embedded Figures (.18)

Paper Folding (.12)

Sex Difference No Sex Difference

Possible Causal Factors

Nature• Evolutionary pressures

on males and females• Heredity (twin studies)• Hormones

– In development

– Across menstrual, daily and yearly cycles

Nurture• Different rearing

practices (toys etc)• Navigation and home

range• Cultural differences• Cohort effects

Beyond Sex Differences

“ As a society, our focus should e on the optimization of spatial ability in all individuals, rather than a focus on rank ordering of the sexes”

“ this long-standing debate concerning the causes of sex differences in certain spatial abilities, although scientifically interesting, has diverted attention from a much more important point; that there is currently plenty of evidence to conclude that spatial skill is trainable, for both sexes”

Newcombe, Mathason, and Terlecki (2003)

Training of Spatial Abilities

Training of Spatial Abilities

• Several isolated studies, short term, no large systematic research program

• Types of Studies:– Effects of learning subject matter content– Effects of Practice– Teaching Strategies– “Visualizing” what people have to imagine

Can Spatial Abilities be Trained?

• Several studies have shown that spatial abilities can be improved by a small amount of training

• Issues of how far this training tranfers

• More extensive, longer range studies needed

Does Initial Spatial Ability determine Final Success?

• Studies of spatial abilities in skill acquisition– Spatial ability may be more important at early

stages of training– Students of all abilities able to learn, but at

different rates

• Is this true for all spatial tasks?

Focus on Cross Sections

Importance of Cross-Sections

engineering

microbiology

cognitiveneuroscience astronomy

anatomy meteorology physics geology

Problem

• Object to be understood has an internal 3-D structure

• Representation medium (printed page or computer screen) is 2-D

Three Dimensional Perception

Depth Cues

Pictorial: e.g. linear perspective, occlusion

Binocular: e.g., binocular disparity

Motion based: e.g., motion parallax

3-D Perception

• Only pictorial cues available in a static diagram

• Animation can also provide motion-based cues– Motion parallax– Accretion and Deletion

Current Research Program

• Task: Draw the cross-section that would result when a 3-dimensional structure is sliced

• Measured spatial ability

• Animations available– Interactive– Non-interactive

What Students RepresentImagine the object is sliced at the line and draw the cross section

Preliminary Results

• Drawing performance highly correlated with spatial ability

• Performance improves, especially for low-spatial individuals– When they are shown an “instructional” video, of how

to draw a cross-section

– When they are exposed to an interactive animation

• Similar results found in research on instructional animations in anatomy

Conclusions

Conclusions

• There are large individual differences in spatial perception and visualization ability

• These abilities are influenced but unlikely to be completely determined by nature

• Means of nurturing spatial abilities need more systematic study

• I’m interested in learning what has worked for you…