Lateral and vertical attentional biases in normal individuals.
BACKGROUND
When normal people attempt to bisect lines they often make their mark to the left of midline (pseudoneglect) and when attempting to bisect radial lines normal people tend to bisect distal to the actual midline. These biases might be related to asymmetrical activation induced by making spatial computations or attention-intentional preferences. The purpose of this study was to learn if in the absence of spatial computations normal subjects would demonstrate a left and upward bias.


METHODS
Normal subjects (139) were given 8 pegs and asked to place these pegs anywhere on a 2-foot-square board.


RESULTS
Overall, the subjects displaced the pegs to the left and upward.


CONCLUSIONS
The overall left-distal bias observed in this experiment was not induced by spatial computation or misperceptions, but is consistent with the postulate that the right hemisphere is dominant for attention-intention and has a relatively distal bias.
Drago
Valeria
V
Department of Neurology, Malcom Randall VAMC Research Service, University of Florida, Gainesville, Florida, USA. valeria.drago@neurology.ufl.edu
Foster
Paul S
PS
Webster
Daniel G
DG
Crucian
Gregory P
GP
Heilman
Kenneth M
KM
D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D016010:Binomial Distribution; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000503:physiopathology*; D012016:Reference Values; D013028:Space Perception / Q000502:physiology*