Neural dynamics underlying the development of selective attention mechanisms

Selective attention plays a crucial role in prioritizing relevant sensory information and filtering out distractions. Several theories of attention have posited that this process involves the fronto-parietal network sending top-down signals to enhance the selectivity of spatial tuning of neural populations in upstream visual areas. However, the developmental trajectory and temporal dynamics of these neural computations as well as their contribution to adult-level selective attention functions remain poorly understood. Here, we investigated these mechanisms by recording EEG from typically developing Thai children (6-12 years), adolescents (13-18 years), and adults (20-33 years) during an attention-cueing Eriksen flanker task. We used the inverted encoding model (IEM) to examine the temporal dynamics of selective visuospatial attention based on alpha band oscillations (8-12Hz) in the EEG data. Our alpha-based IEM analysis yielded two key findings. First we observed an increase in tuning selectivity of the alpha-based spatial reconstructions with higher attention demand (i.e., incongruent vs. congruent stimuli) from ~50-250 ms after the target onset in adults, while no such increase was evident in children or adolescents. Second, the temporal dynamics of alpha-based spatial representations differed across age groups. In children and adolescents, cue-induced increases in tuning selectivity emerged very early (around 50ms after the cue onset) and persisted throughout the cue and stimulus periods. In contrast, adults initially exhibited no tuning selectivity in the alpha-based reconstructions near the cue onset. However, as time progressed, the tuning selectivity of the alpha-based spatial representations increased rapidly until reaching the target onset, followed by a sharp decline after the target onset unlike the alpha-based spatial reconstructions that sustained throughout the entire stimulus period in the younger groups. These findings shed light on the developmental trajectory of selective attention mechanisms and highlight distinct patterns of neural dynamics in the alpha band frequencies that support the neurodevelopment of selective attention.