Development of Thalamocortical Connectivity during Infancy and Its Cognitive Correlations

Abstract

Although commonly viewed as a sensory information relay center, the thalamus has been increasingly recognized as an essential node in various higher-order cognitive circuits, and the underlying thalamocortical interaction mechanism has attracted increasing scientific interest. However, the development of thalamocortical connections and how such development relates to cognitive processes during the earliest stages of life remain largely unknown. Leveraging a large human pediatric sample (N ϭ 143) with longitudinal resting-state fMRI scans and cognitive data collected during the first 2 years of life, we aimed to characterize the age-dependent development of thalamocortical connectivity patterns by examining the functional relationship between the thalamus and nine cortical functional networks and determine the correlation between thalamocortical connectivity and cognitive performance at ages 1 and 2 years. Our results revealed that the thalamus-sensorimotor and thalamus-salience connectivity networks were already present in neonates, whereas the thalamusmedial visual and thalamus-default mode network connectivity emerged later, at 1 year of age. More importantly, brain-behavior analyses based on the Mullen Early Learning Composite Score and visual-spatial working memory performance measured at 1 and 2 years of age highlighted significant correlations with the thalamus-salience network connectivity. These results provide new insights into the understudied early functional brain development process and shed light on the behavioral importance of the emerging thalamocortical connectivity during infancy.

Specialization and integration of functional thalamocortical connectivity in the human infant

“…Studies of longitudinal development of thalamocortical connectivity have used adult-defined cortical regions of interest and analyzed thalamic correlations to these areas in neonates and children rather than using areas of cortical activity that are coherent at the time of normal birth as in this study. This methodological difference, perhaps, accounts for the difference in results found (33).…”

Early Development of Executive Attention

“…Cortical grey volume also increases substantially in the first two years of life, with a faster growth of frontal structures during the second year of age [39,40]. There is also an increment in the thalamo-cortical connections during the first two years of life that has been related to toddlers' working memory skills and general cognitive development [41]. These structural changes correspond to the restructuring of the network configuration, leading to more efficient and stronger connections that has been also related to a general increase in the modularity of the different brain networks in toddlerhood [37].…”

The emergence of functional architecture during early brain development

“…Although the developmental trajectories of resting state networks and neurodevelopmental milestones display remarkable similarities, cross-correlation studies linking findings on functional networks to behavioral measures during early development are sparse (Alcauter et al, 2015b(Alcauter et al, , 2014. A longitudinal study assessing functional brain network development and their cognitive correlates in 74 infants found functional connectivity between the thalamus and the immature salience network at age one year to be associated with working memory performance at age two (Alcauter et al, 2014).…”

“…A longitudinal study assessing functional brain network development and their cognitive correlates in 74 infants found functional connectivity between the thalamus and the immature salience network at age one year to be associated with working memory performance at age two (Alcauter et al, 2014).…”

“…Similar to the adult connectome, the neonatal brain has repeatedly been found to display short characteristic path length, which is computed as the average number of edges that need to be Schematic overview based on findings by (Alcauter et al, 2014;Bystron et al, 2008;Gao et al, 2011;Innocenti and Price, 2005;Kostovic et al, 2014;Kostovic and Rakic, 1980;Kostovic and Vasung, 2009;Shankle et al, 1999;Stiles and Jernigan, 2010;Thomason et al, 2013Thomason et al, , 2015Vanhatalo and Kaila, 2006;Vasung et al, 2010) (Huang et al, 2009;Kostovic and Jovanov-Milosevic, 2006;Takahashi et al, 2012;Vasung et al, 2010). (Doria et al, 2010a;Gao et al, 2014a;Smyser et al, 2010;Thomason et al, 2015).…”