Working Memory Performance in Typically Developing Children and Adolescents: Behavioral Evidence of Protracted Frontal Lobe Development

Abstract

Post-mortem histological and in vivo neuroimaging findings both reveal frontal lobe development that extends beyond the adolescent years. Few studies have examined whether this protracted neurodevelopment coincides with improvements in adolescent performance on putative frontal lobe tasks. An instrumental function supported by the frontal lobes is working memory, the ability to maintain and manipulate information online. This study investigated the performance of typically developing children and adolescents on a battery of working memory tasks. Findings revealed an improvement in performance on most working memory tasks across the adolescent years. In contrast, no improvement was observed on tasks largely supported by more posterior neural substrates. Current findings indicate a similar unfolding of the executive aspects of verbal working memory as previously demonstrated with spatial working memory. Factor analysis revealed a grouping of working memory tasks based largely on task demands, irrespective of working memory domain, adding support for process-specific models of prefrontal organization. Important implications for typical and atypical frontal lobe development are discussed.

Differences in brain morphology and working memory capacity across childhood

“…Distinct factors were identified for verbal and visuo‐spatial storage with an additional factor contributing to tasks with a higher executive demand load regardless of domain (see also Alloway et al., 2004; Bayliss et al., 2003; Kane et al., 2007). Factor scores were linearly related to age for all factors, replicating previous studies that indicate linear increases in short‐term and working memory capacity throughout childhood and adolescence (Conklin, Luciana, Hooper, & Yarger, 2007; Gathercole et al., 2004; Swanson, 1999). …”

A social neuroscience perspective on adolescent risk-taking

“…Generally speaking, performance on tasks that activate the frontal lobes continues to improve through middle adolescence (until about age 16 on tasks of moderate difficulty), in contrast to performance on tasks that activate more posterior brain regions, which reaches adult levels by the end of preadolescence (Conklin, Luciana, Hooper, & Yarger, 2007). Improved executive function in adolescence is reflected in better performance with age on tasks known to activate the dorsolateral prefrontal cortex, such as relatively difficult tests of spatial working memory (Conklin et al, 2007) or especially challenging tests of response inhibition (Luna et al, 2001); and the ventromedial prefrontal cortex, such as the Iowa Gambling Task (Crone & van der Molen, 2004;Hooper, Luciana, Conklin, & Yarger, 2004).…”

“…Improved executive function in adolescence is reflected in better performance with age on tasks known to activate the dorsolateral prefrontal cortex, such as relatively difficult tests of spatial working memory (Conklin et al, 2007) or especially challenging tests of response inhibition (Luna et al, 2001); and the ventromedial prefrontal cortex, such as the Iowa Gambling Task (Crone & van der Molen, 2004;Hooper, Luciana, Conklin, & Yarger, 2004). Although some tests of executive function simultaneously activate both the dorsolateral and ventromedial regions, there is some evidence that the maturation of these regions may take place along somewhat different timetables, with performance on exclusively ventromedial tasks reaching adult levels somewhat earlier than performance on exclusively dorsolateral tasks (Conklin et al, 2007;Hooper et al, 2004).…”

“…Improved executive function in adolescence is reflected in better performance with age on tasks known to activate the dorsolateral prefrontal cortex, such as relatively difficult tests of spatial working memory (Conklin et al, 2007) or especially challenging tests of response inhibition (Luna et al, 2001); and the ventromedial prefrontal cortex, such as the Iowa Gambling Task (Crone & van der Molen, 2004;Hooper, Luciana, Conklin, & Yarger, 2004). Although some tests of executive function simultaneously activate both the dorsolateral and ventromedial regions, there is some evidence that the maturation of these regions may take place along somewhat different timetables, with performance on exclusively ventromedial tasks reaching adult levels somewhat earlier than performance on exclusively dorsolateral tasks (Conklin et al, 2007;Hooper et al, 2004). In one recent study of age differences in cognitive performance using tasks known to differentially activate these two prefrontal regions, there was age-related improvement into middle adolescence on both types of tasks, but there were no significant correlations between performance on the ventromedial and dorsolateral tasks, suggesting that maturation of the ventromedial prefrontal cortex may be a developmentally distinct process from the maturation of the dorsolateral prefrontal cortex (Hooper et al, 2004).…”

Performance on tasks of visuospatial memory and ability: A cross-sectional study in 330 adolescents aged 11 to 20

“…Firstly, visuospatial memory has often been studied in younger children (Alloway et al, 2006;Cestari et al, 2007;Heyes et al, 2012) and in small groups, with performance collapsed and averaged over various age ranges (Conklin, Luciana, Hooper, & Yarger, 2007;Gathercole et al, 2004) and. More specifically, results of participants with an age in the latter part of adolescence, if at all represented, are mostly grouped together with young adults (Luciana & Nelson, 2002;Rowe, Hasher, & Turcotte, 2009;van Leijenhorst, Crone, & Van der Molen, 2007).…”