title: Relational complexity modulates activity in the prefrontal cortex during numerical inductive reasoning: an fMRI study.
abstract: Most previous studies investigating relational reasoning have used visuo-spatial materials. This fMRI study aimed to determine how relational complexity affects brain activity during inductive reasoning, using numerical materials. Three numerical relational levels of the number series completion task were adopted for use: 0-relational (e.g., "23 23 23"), 1-relational ("32 30 28") and 2-relational ("12 13 15") problems. The fMRI results revealed that the bilateral dorsolateral prefrontal cortex (DLPFC) showed enhanced activity associated with relational complexity. Bilateral inferior parietal lobule (IPL) activity was greater during the 1- and 2-relational level problems than during the 0-relational level problems. In addition, the left fronto-polar cortex (FPC) showed selective activity during the 2-relational level problems. The bilateral DLPFC may be involved in the process of hypothesis generation, whereas the bilateral IPL may be sensitive to calculation demands. Moreover, the sensitivity of the left FPC to the multiple relational problems may be related to the integration of numerical relations. The present study extends our knowledge of the prefrontal activity pattern underlying numerical relational processing.
authors.affiliation: Department of Teacher Education, Shanxi Normal University, Linfen 041004, China; Key laboratory for Cognition and Personality of Ministry of Education, Southwest University, Chongqing 400715, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Feng
authors.affiliation: Research Centre for Brain Function and Psychological Science, Shenzhen University, Shenzhen 518060, China.
authors.forename: Li
authors.initials: L
authors.lastname: Peng
authors.affiliation: Key laboratory for Cognition and Personality of Ministry of Education, Southwest University, Chongqing 400715, China.
authors.forename: Long
authors.initials: L
authors.lastname: Chang-Quan
authors.affiliation: Research Centre for Brain Function and Psychological Science, Shenzhen University, Shenzhen 518060, China. Electronic address: leiyi821@vip.sina.com.
authors.forename: Lei
authors.initials: L
authors.lastname: Yi
authors.affiliation: Research Centre for Brain Function and Psychological Science, Shenzhen University, Shenzhen 518060, China; Key laboratory for Cognition and Personality of Ministry of Education, Southwest University, Chongqing 400715, China. Electronic address: lihongwrm@vip.sina.com.
authors.forename: Li
authors.initials: L
authors.lastname: Hong
mesh_terms: D000328:Adult; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010296:Parietal Lobe / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology*; D013850:Thinking / Q000502:physiology*; D055815:Young Adult
keywords: Dorsolateral prefrontal cortex; Fronto-polar cortex; Numerical inductive reasoning; Relational complexity