| |
Abstract:
Abstract: Previous research investigating hemispheric
asymmetries for categorical and coordinate decisions with
visuospatial stimuli has revealed a task by visual field
interaction in the direction of a left visual field advantage for
coordinate (near/far) processing and a right visual field advantage
for categorical (above/below) processing. The present experiments
were designed to examine whether these asymmetries for categorical
and coordinate decisions would extend to conceptual and temporal
domains. Three visual half-field experiments using number, letter
and temporal stimuli (two dots with varying onsets) were performed.
Categorical decisions were either greater/less than decisions (with
numbers), before/after decisions (with letters), or to decide which
dot appeared first on the computer screen. Coordinate decisions
were either within/beyond decisions (are two numbers or two letters
within 5 units of each other) or to decide if the interval between
the onset of the two dots was longer or shorter than 30
milliseconds. There were significant left visual field advantages
for making coordinate decisions, less consistent right visual field
advantages for making categorical decisions and a significant
interactions of task and visual field in each experiment. This
pattern is consistent with the direction of asymmetries reported
with visuospatial stimuli. When performing categorical and
coordinate tasks, the link between perceptual, conceptual, and
temporal processing may be the extent to which each hemisphere
engages in coarse coding as a processing strategy.
|
