Cortical thickness of superior frontal cortex predicts impulsiveness and perceptual reasoning in adolescence

Abstract

Impulsiveness is a pivotal personality trait representing a core domain in all major personality inventories. Recently, impulsiveness has been identified as an important modulator of cognitive processing, particularly in tasks that require the processing of large amounts of information. Although brain imaging studies have implicated the prefrontal cortex to be a common underlying representation of impulsiveness and related cognitive functioning, to date a fine-grain and detailed morphometric analysis has not been carried out. On the basis of ahigh-resolution magnetic resonance scans acquired in 1620 healthy adolescents (IMAGEN), the individual cortical thickness (CT) was estimated. Correlations between Cloninger's impulsiveness and CT were studied in an entire cortex analysis. The cluster identified was tested for associations with performance in perceptual reasoning tasks of the Wechsler Intelligence Scale for Children (WISC IV). We observed a significant inverse correlation between trait impulsiveness and CT of the left superior frontal cortex (SFC; Monte Carlo Simulation P<0.01). CT within this cluster correlated with perceptual reasoning scores (Bonferroni corrected) of the WISC IV. On the basis of a large sample of adolescents, we identified an extended area in the SFC as a correlate of impulsiveness, which appears to be in line with the trait character of this prominent personality facet. The association of SFC thickness with perceptual reasoning argues for a common neurobiological basis of personality and specific cognitive domains comprising attention, spatial reasoning and response selection. The results may facilitate the understanding of the role of impulsiveness in several psychiatric disorders associated with prefrontal dysfunctions and cognitive deficits.

Substance abuse risk in emerging adults associated with smaller frontal gray matter volumes and higher externalizing behaviors

“…Our finding that the young adult ER subjects had previously reported more externalizing behaviors is consistent with prior working showing associations between externalizing measures and substance abuse risk (Benegal et al, 2007; Bava and Tapert, 2010). In addition, the negative associations between these early adolescent behavior scores and the subjects’ current frontal cortical volumes are in agreement with a recent report that left superior frontal cortical thickness in adolescents was negatively related to impulsiveness, another behavioral measure associated with risk (Schilling et al, 2013). The substance risk variable used in this study was created from measures of early engagement with substances, so, in agreement with the early externalizing measures, further links early behaviors with frontal cortical volumes.…”

Common Neural Correlates of Intertemporal Choices and Intelligence in Adolescents

“…This theory was further supported by studies showing that higher scores in measures of intelligence were related to higher gray matter volume in these areas (Colom et al, 2009;Karama et al, 2009;Johnson, Jung, Colom, & Haier, 2008). Recently, higher cortical thickness of the superior frontal cortex has been proposed as common neural basis of intelligence and impulsivity (Schilling et al, 2013) indicating a potential overlap in brain networks underlying both behaviors.…”

Development and aging of cortical thickness correspond to genetic organization patterns

“…Several recent studies have found thinner cortex to be predictive of favorable cognitive development in school age years in a variety of cognitive domains (31-37), as well as in neurodevelopmental conditions such as schizophrenia (28,38). However, it is important to note that also positive associations between cognitive function and cortical thickness have been found in childhood and adolescence (39,40) and that symptoms of neurodevelopmental conditions and risk factors have been associated with thinner cortex as well (41)(42)(43)(44), even in age-varying ways (45,46) [see Vuoksimaa et al for a more in-depth discussion on the relationship between cortical thickness and general cognitive abilities (47)]. These different effects may be due to offset differences between groups and/ or differences in change rates and indicate a complex relationship between symptoms and cortical developmental markers (48,49) that likely depends on the condition in question, cortical region, and age.…”