Neural mechanisms underlying the income-achievement gap: the role of the ventral visual stream
Children from low-socioeconomic status (SES) households have lower academic achievement than their higher-SES peers. Growing evidence suggests that SES-related differences in brain regions supporting higher-order cognitive abilities may contribute to these differences in achievement. We investigate a novel hypothesis that differences in earlier-developing sensory networks—specifically the ventral visual stream (VVS), which is involved in processing visual stimuli—contribute to SES-related disparities in attention, executive functions, and academic outcomes. In a sample of children (6-8 years, n = 62), we use fMRI to investigate SES-related differences in neural function during two attentional tasks associated with academic achievement and involving interaction between visual processing and top-down control: (i) cued attention—the ability to use an external visual cue to direct spatial attention, and (ii) memory-guided attention—the ability to use past experience to direct spatial attention. SES-related differences emerged in recruitment of the anterior insula, inferior frontal gyrus, and VVS during cued attention. Critically, recruitment of the VVS during both tasks was associated with executive functions and academic achievement. VVS activation during cued attention mediated SES-related differences in academic achievement. Further, the link between VVS activation during both attention tasks and academic achievement was mediated by differences in executive functioning. These findings extend previous work by highlighting that (i) early-developing visual processing regions play an important role in supporting complex attentional processes, (ii) childhood SES is associated with VVS development, and (iii) individual differences in VVS function may be a neural mechanism in the emergence of the income-achievement gap.