title: Neural correlates of superior intelligence: stronger recruitment of posterior parietal cortex.
abstract: General intelligence (g) is a common factor in diverse cognitive abilities and a major influence on life outcomes. Neuroimaging studies in adults suggest that the lateral prefrontal and parietal cortices play a crucial role in related cognitive activities including fluid reasoning, the control of attention, and working memory. Here, we investigated the neural bases for intellectual giftedness (superior-g) in adolescents, using fMRI. The participants consisted of a superior-g group (n = 18, mean RAPM = 33.9 +/- 0.8, >99%) from the national academy for gifted adolescents and the control group (n = 18, mean RAPM = 22.8 +/- 1.6, 60%) from local high schools in Korea (mean age = 16.5 +/- 0.8). fMRI data were acquired while they performed two reasoning tasks with high and low g-loadings. In both groups, the high g-loaded tasks specifically increased regional activity in the bilateral fronto-parietal network including the lateral prefrontal, anterior cingulate, and posterior parietal cortices. However, the regional activations of the superior-g group were significantly stronger than those of the control group, especially in the posterior parietal cortex. Moreover, regression analysis revealed that activity of the superior and intraparietal cortices (BA 7/40) strongly covaried with individual differences in g (r = 0.71 to 0.81). A correlated vectors analysis implicated bilateral posterior parietal areas in g. These results suggest that superior-g may not be due to the recruitment of additional brain regions but to the functional facilitation of the fronto-parietal network particularly driven by the posterior parietal activation.
authors.affiliation: School of Biological Sciences, Seoul National University, Seoul 151-742, South Korea. leekho@snu.ac.kr
authors.forename: Kun Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Yu Yong
authors.initials: YY
authors.lastname: Choi
authors.forename: Jeremy R
authors.initials: JR
authors.lastname: Gray
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Cho
authors.forename: Jeong-Ho
authors.initials: JH
authors.lastname: Chae
authors.forename: Seungheun
authors.initials: S
authors.lastname: Lee
authors.forename: Kyungjin
authors.initials: K
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D005625:Frontal Lobe / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007206:Individuality; D007360:Intelligence / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D010296:Parietal Lobe / Q000502:physiology*; D011594:Psychometrics; D011597:Psychomotor Performance / Q000502:physiology; D011999:Recruitment, Neurophysiological / Q000502:physiology*; D014888:Wechsler Scales