ACC Sulcal Patterns and Their Modulation on Cognitive Control Efficiency Across Lifespan: A Neuroanatomical Study on Bilinguals and Monolinguals

Abstract

The anterior cingulate cortex (ACC) is a key structure implicated in the regulation of cognitive control (CC). Previous studies suggest that variability in the ACC sulcal pattern-a neurodevelopmental marker unaffected by maturation or plasticity after birth-is associated with intersubject differences in CC performance. Here, we investigated whether bilingual experience modulates the effects of ACC sulcal variability on CC performance across the lifespan. Using structural MRI, we first established the distribution of the ACC sulcal patterns in a large sample of healthy individuals (N = 270) differing on gender and ethnicity. Second, a participants' subsample (N = 157) was selected to test whether CC performance was differentially affected by ACC sulcation in bilinguals and monolinguals across age. A prevalent leftward asymmetry unaffected by gender or ethnicity was reported. Sulcal variability in the ACC predicted CC performance differently in bilinguals and monolinguals, with a reversed pattern of structure-function relationship: asymmetrical versus symmetrical ACC sulcal patterns were associated with a performance advantage in monolinguals and a performance detriment to bilinguals and vice versa. Altogether, these findings provide novel insights on the dynamic interplay between early neurodevelopment, environmental background and cognitive efficiency across age.

Sulcal Pattern Variability and Dorsal Anterior Cingulate Cortex Functional Connectivity Across Adult Age

“…dorsal and parallel to the cingulate sulcus (CS) on the medial surface of the ACC (Ono et al, 1990;Paus et al, 1996;Yücel et al, 2001). Here, following Ono and colleagues' nomenclature (Ono et al, 1990), as in our previous studies (Cachia et al, 2017;Del Maschio et al, 2019), two types of dACC sulcation were identified depending on the PCS occurrence in each hemisphere: a ''single'' type (CS only) and a ''double parallel'' type (CS and additional PCS) ( Fig. 1a, b).…”

“…Following Garrison's PCS measurement protocol (Garrison, 2017), first reported in Garrison and colleagues (2015), all T1 images were imported into MANGO (Multiimage Analysis GUI, v 4.0, http://ric.uthscsa.edu/mango/ mango.html, The University of Texas Health Science Center; see also Del Maschio et al, 2019). The CS was identified at 4 mm laterally from the midline (x = 0) on either hemisphere, lying dorsal to the corpus callosum.…”

Cognitive Persistence and Executive Function in the Multilingual Brain During Aging

“…Late, older adult bilinguals were faster overall and had less skewed RT distributions on incongruent trials on the Flanker task compared to older adult monolinguals (Abutalebi et al, 2015). Age-related performance declines on ANT and Flanker tasks were larger in monolinguals than in bilinguals (Borsa et al, 2018;Del Maschio et al, 2019), indicating that only monolinguals became more susceptible to interference from distractors with age. Across the lifespan, bilinguals produce fewer total errors on the Stroop task (Massa et al, 2020) and have a smaller Stroop effect than monolinguals (Bialystok et al, 2008;Incera and McLennan, 2018), even after accounting for bilinguals' reduced automaticity of word processing (Bialystok et al, 2008).…”

“…Moreover, aging was associated with decreased gray matter volume of IFG bilaterally in monolinguals, but only in the left-hemisphere for bilinguals (Borsa et al, 2018). These structural changes in older multilingual adults are accompanied by diminished cognitive decline (e.g., less age-related slowing on the Flanker task; Abutalebi et al, 2015;Del Maschio et al, 2019) and altered structure-function relationships between cingulo-opercular regions and cognitive control (Borsa et al, 2018;Del Maschio et al, 2019). For instance, higher ACC volume was associated with smaller conflict effects on the ANT in middle-aged to older bilinguals but not in monolinguals (Borsa et al, 2018), indicating that ACC is related to cognitive control function during healthy aging for bilinguals only.…”

“…The evidence reviewed in section "Cognitive Persistence in Multilingualism" demonstrates that the experience of multilingualism affects the cingulo-opercular network, which I have argued is responsible for cognitive persistence, the willingness or ability to implement mental effort. Compared to monolinguals, multilinguals exhibit structural and functional differences in cingulo-opercular regions across the lifespan (Gold et al, 2013b;Abutalebi et al, 2015;Grady et al, 2015;Kousaie and Phillips, 2017;Borsa et al, 2018;Del Maschio et al, 2019). In older adults, these differences have been associated with superior performance on challenging tasks requiring cognitive control (Gold et al, 2013b;Abutalebi et al, 2015;Kousaie and Phillips, 2017) and may delay the onset of cognitive symptoms in some types of dementia (Bialystok et al, 2007;Craik et al, 2010;Perquin et al, 2013;Alladi et al, 2017).…”