The Spatial Intelligence & Learning Center is composed of the following universities and is funded by an NSF
Science of Learning Centers grant.
Sensing the Slopes: Sensory Modality Effects on a Goal Location TaskSteven Weisberg1, Daniele Nardi2, Nora Newcombe1, & Thomas Shipley1
1Temple University, 2Sapienza University of Rome
Sex Differences
Egocentric/Allocentric?Introduction
Apparatus and Procedure
Terrain slope is a salient spatial cue, useful in spatial orientation for humans. However, males use slope cues more reliably than females (e.g., Nardi, Newcombe, & Shipley, 2011; 2012). We designed a goal location study to investigate 3 questions.
1. Can slope be represented only visually or only kinesthetically?
2. Are gender differences in using slope modulated by sensory modality?
3. Is there a preference for egocentric or allocentric representation of slope (e.g., Shelton & McNamara, 2001)? And, does this vary by sensory modality?
Participants learned the location of the goal either while seated in the chair (visual-only), while standing up but blindfolded (kinesthetic-only condition), or while standing up and could see (combined). They were then disoriented, and asked to point to the goal after being told they were facing either uphill or downhill.
1. Slope can be accurately coded visually OR kinesthetically.2. Sex differences:
• Males performed more accurately in the kinesthetic condition, but females were more accurate in the visual condition.
• Performance correlated with MRT for males, but WLT for women.
3. Error patterns and reaction time provided evidence for an egocentric encoding of slope.
Slope is specified in the environment by visual and kinesthetic information. In the real world, these senses normally reinforce each other.
Visual Kinesthetic Combined0
5
10
15
20
25
30
35Encoding time by condition
Condition
Enco
ding
Tim
e (s
)
*
Visual Kinesthetic Combined0
20
40
60
80
100
120
Sensory Modality By Sex Interaction
Female
Male
Condition
Perc
ent C
orre
ct*
Chance = 25%
Effect of Sensory Modality
Participants were faster only for concordant compared to discordant trials (discarding 2 participants who were wrong on all trials), not for facing direction or goal location. This is strong evidence for an egocentric reference frame.
Variable MRT WLT SOT SBSOD Correct Trials
MRT – .36 -.40 .08 .67**WLT -0.02 – -.60** .06 .18SOT -0.50* -0.35 – -.24 -.38
SBSOD 0.06 0.16 0.04 – -.04Correct Trials 0.13 0.47* -0.42* -0.37 –
Male (above the diagonal) performance on the goal location task was significantly correlated with the Mental Rotation Test (MRT). Female performance (below the diagonal) was significantly correlated with the Water Level Test (WLT). SOT = Spatial Orientation Test, SBSOD = Santa Barbara Sense of Direction.
Correlations Varied by Sex
Orthogonal Vertical Diagonal0
10
20
30
Error Type by Alignment Ef-fect
DiscordantConcordant
Error Type
Tota
l # E
rror
s
Trials were either concordant (facing direction = goal) or discordant (facing direction ≠ goal) during retrieval. Participants committed orthogonal errors more on discordant trials, suggesting that slope was a highly salient axis , and that participants used an egocentric reference frame.
Conclusions
Con-cordant
Discordant Facing Up Facing Down
Goal Up Goal Down
0
2
4
6
8
10
12
Difference in RT by Trial Type
Trial Type
Rea
ctio
nTim
e
*
