SA67 - A NEURAL SIGNATURE OF MALLEABILITY: GENERAL INTELLIGENCE CORRELATES WITH VENTRAL STRIATAL ACTIVATION AND EPIGENETIC MARKERS OF DOPAMINE NEUROTRANSMISSION

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Background General intelligence has a substantial genetic background in children, adolescents, and adults, but environmental factors also strongly correlate with cognitive performance as evidenced by a strong (up to one SD) increase in average intelligence test results in the second half of the previous century. This change occurred in a period apparently too short to accommodate radical genetic changes. It is highly suggestive that environmental factors interact with genotype by possible modification of epigenetic factors that regulate gene expression and thus contribute to individual malleability. This modification might as well be reflected in recent observations of an association between dopamine-dependent encoding of reward prediction errors and cognitive capacity, which was modulated by adverse life events. Methods In a cohort of 1475 young healthy human subjects of both sexes from the IMAGEN sample, general IQ was estimated based on a principal component analysis of WISC-IV scores. As predictors we used functional brain activation elicited by temporarily surprising reward-predicting cues (BOLD-signal) during performance of the MID-task, a polygenic score for intelligence based on previously reported results (Benyamin et al. 2014) and methylation count in cg rich islands relevant for dopaminergic neurotransmission. Results Here we show that general IQ in adolescents is positively associated with 1) functional activation elicited by temporarily surprising reward-predicting cues, 2) a polygenic score for intelligence in children, and negative with 3) epigenetic markers for dopamine neurotransmission. With respect to components of general IQ, fluid IQ was associated with striatal functional activation, and crystallized IQ more strongly correlated with the genetic score and epigenetic markers. Discussion Our results demonstrate a neurobiological correlate of the malleability of general IQ and point to the importance of epigenetic mechanisms influencing dopamine neurotransmission. Peripheral epigenetic markers are in need of confirmation in the central nervous system and should be tested in longitudinal settings specifically assessing individual and social stress factors that can modify epigenetic structure.