Temporo-parietal connectivity uniquely predicts reading change from childhood to adolescence

Abstract

Previous research has shown that left posterior middle temporal gyrus (pMTG) is a core node in the semantic network, and cross-sectional studies have shown that activation in this region changes developmentally and is related to skill measured concurrently. However, it is not known how functional connectivity with this region changes developmentally, and whether functional connectivity is related to future gains in reading. We conducted a longitudinal functional magnetic resonance imaging (fMRI) study in 30 typically developing children (aged 8–15) to examine whether initial brain measures, including activation and connectivity, can predict future behavioral improvement in a semantic judgment task. Participants were scanned on entering the study (time 1) and a follow-up period of 2 years (time 2). Character pairs were arranged in a continuous variable according to association strength (i.e. strong versus weak), and participants were asked to determine if these visually presented pairs were related in meaning. Our results demonstrated greater developmental changes from time 1 to time 2 for weaker association pairs in the left pMTG for the children (aged 8–11) as compared to the adolescents (aged 12–15). Moreover, the results showed greater developmental changes from time 1 to time 2 for weaker association pairs in connectivity between the pMTG and inferior parietal lobule (IPL) for the children as compared to the adolescents. Furthermore, a hierarchical stepwise regression model revealed that connectivity between the pMTG and IPL in weak association pairs was uniquely predictive of behavioral improvement from time 1 to time 2 for the children, but not the adolescents. Taken together, the activation results suggest relatively rapid development before adolescence of semantic representations in the pMTG. Moreover, the connectivity results of pMTG with IPL tentatively suggest that early development of semantic representations may be facilitated by enhanced engagement of phonological short-term memory.

Early Phonological Neural Specialization Predicts Later Growth in Word Reading Skills

“…Much of this research has focused on behavioral predictors, such as performance on various standardized measures. However, researchers within the last few decades have begun to extend this work by exploring the use of language-related brain-based predictors (e.g., Lee et al, 2016;Linkersdorfer et al, 2014;McNorgan et al, 2011;Preston et al, 2016;Smith et al, 2018). A subset of this research, which has examined the use of both behavioral and neural predictors, has shown that both functional-and structural-based neural measures explain unique variance in reading growth over that of purely behavioral measures (e.g., Bach et al, 2013;Hoeft et al, 2007;Hoeft et al, 2011;Maurer et al, 2009).…”

Mechanisms of interactive specialization and emergence of functional brain circuits supporting cognitive development in children

“…In order to make direct links to cognition and test-specific hypotheses arising from the IS model of brain development, longitudinal task-based fMRI studies are critically needed. There have only been six longitudinal developmental fMRI studies of task-related activation, [16][17][18][19][20] with only one study examining changes in brain connectivity. 21 Furthermore, extant studies of growth trajectories using longitudinal designs have focused on regional changes in brain response.…”

Differences between child and adult large‐scale functional brain networks for reading tasks

“…Traditional functional connectivity analysis focusing only on seed regions (e.g., VWFA and IFG in the aforementioned studies) fails to give a complete picture of brain connectivity profiles. The seed regions selected in most previous studies on reading development are mainly located in the left hemisphere (Bitan, ; Bitan et al, ; Lee et al, ) or in classic cortical regions for reading (Koyama et al, ). However, numerous studies (Banai et al, ; Liu et al, ; Price, ) have found that reading also involves regions beyond the left‐lateralized classic reading network, such as limbic and subcortical regions (Banai et al, ; Hornickel, Skoe, Nicol, Zecker, & Kraus, ), low‐level visual perception regions (Liu et al, ; Price, ; Sun, Yang, Desroches, Liu, & Peng, ), and high‐level executive function regions (Lee et al, ; Price, ; Whitney, Jefferies, & Kircher, ).…”

“…A recent longitudinal study investigated how the functional connectivity of the left posterior middle temporal gyrus (pMTG) in a visual semantic judgment task changed over development. It revealed longitudinal increases in functional connectivity between the pMTG and the inferior parietal lobule (IPL) for weak semantic association word pairs and suggested that early development of semantic representations may be facilitated by enhanced engagement of phonological short‐term memory (Lee, Booth, & Chou, ).…”