title: Space, time, and numbers in the right posterior parietal cortex: Differences between response code associations and congruency effects.
abstract: The mental representations of space, time, and number magnitude are inherently linked. The right posterior parietal cortex (PPC) has been suggested to contain a general magnitude system that underlies the overlap between various perceptual dimensions. However, comparative studies including spatial, temporal, and numerical dimensions are missing. In a unified paradigm, we compared the impact of right PPC inhibition on associations with spatial response codes (i.e., Simon, SNARC, and STARC effects) and on congruency effects between space, time, and numbers. Prolonged cortical inhibition was induced by continuous theta-burst stimulation (cTBS), a protocol for transcranial magnetic stimulation (TMS), at the right intraparietal sulcus (IPS). Our results show that congruency effects, but not response code associations, are affected by right PPC inhibition, indicating different neuronal mechanisms underlying these effects. Furthermore, the results demonstrate that interactions between space and time perception are reflected in congruency effects, but not in an association between time and spatial response codes. Taken together, these results implicate that the congruency between purely perceptual dimensions is processed in PPC areas along the IPS, while the congruency between percepts and behavioral responses is independent of this region.
authors.affiliation: Aging & Cognition Research Group, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany. Electronic address: martin.riemer@dzne.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Riemer
authors.affiliation: Aging & Cognition Research Group, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany. Electronic address: nadine.diersch@dzne.de.
authors.forename: Nadine
authors.initials: N
authors.lastname: Diersch
authors.affiliation: Department of Psychology, School of Social Sciences, University of Mannheim, Mannheim, Germany. Electronic address: f.bublatzky@uni-mannheim.de.
authors.forename: Florian
authors.initials: F
authors.lastname: Bublatzky
authors.affiliation: Aging & Cognition Research Group, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany. Electronic address: thomas.wolbers@dzne.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wolbers
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D055641:Mathematical Concepts; D010296:Parietal Lobe / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013028:Space Perception / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: Mental number line; Mental time line; Posterior parietal cortex; SNARC; Simon effect; Transcranial magnetic stimulation