The involvement of the inferior parietal cortex in the numerical Stroop effect and the distance effect in a two-digit number comparison task.
The neural mechanism of number representation and processing is currently under extensive investigation. In this functional magnetic resonance imaging study, we designed a number comparison task to examine how people represent and compare two-digit numbers in the brain, and whether they process the decade and unit digits in parallel. We manipulated the decade-unit-digit congruency and numerical distance between the pairs of numbers. We observed both Stroop-like interference and the distance effect in the participants' performance. People responded more slowly to incongruent pairs of numbers and pairs of a smaller distance. The inferior parietal cortex showed common and distinct patterns of activation for both attentional selection and number comparison processes, and its activity was modulated by the Stroop-like interference effect and the distance effect. Taken together, these results support both parallel and holistic comparison of two-digit numbers in the brain.
Liu
Xun
X
University of Kentucky, Lexington, USA. xun.liu@uky.edu
Wang
Hongbin
H
Corbly
Christine R
CR
Zhang
Jiajie
J
Joseph
Jane E
JE
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D032882:Comprehension; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008433:Mathematics; D008606:Mental Processes / Q000502:physiology; D008875:Middle Aged; D010296:Parietal Lobe / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D011340:Problem Solving / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*