title: The role of inferior frontal cortex in belief-bias reasoning: an rTMS study.
abstract: The belief-bias effect in syllogistic reasoning refers to the tendency for subjects to be erroneously biased when logical conclusions are incongruent with belief about the world. This study examined the role of inferior frontal cortex (IFC) in belief-bias reasoning using repetitive transcranial magnetic stimulation (rTMS). We used an off-line rTMS method to disrupt IFC activity transiently. Right IFC stimulation significantly impaired incongruent reasoning performance, enhancing the belief-bias effect. Subjects whose right IFC was impaired by rTMS may not be able to inhibit irrelevant semantic processing in incongruent trials. Although left IFC stimulation impaired congruent reasoning, it paradoxically facilitated incongruent reasoning performance, eliminating the belief-bias effect. Subjects whose left IFC was impaired by rTMS may not suffer from interference by irrelevant semantic processing. This study demonstrates for the first time the roles of left and right IFC in belief-bias reasoning using an rTMS approach.
authors.affiliation: Center for Advanced Research on Logic and Sensibility (CARLS), Keio University, Mita 3-1-7, Minato-ku, Tokyo 108-0073, Japan. tuji@flet.keio.ac.jp
authors.forename: Takeo
authors.initials: T
authors.lastname: Tsujii
authors.forename: Sayako
authors.initials: S
authors.lastname: Masuda
authors.forename: Takekazu
authors.initials: T
authors.lastname: Akiyama
authors.forename: Shigeru
authors.initials: S
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D015982:Bias; D001931:Brain Mapping; D003469:Culture; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011340:Problem Solving / Q000502:physiology*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D055815:Young Adult