Heterogeneity in neural network engagement supports individual differences in top-down attention

Top-down attention enables selective prioritisation of goal-relevant information, yet how attentional control varies across individuals remains unclear, particularly in relation to sensory processing. Here, we combined magnetoencephalography (MEG) and pupillometry--in older adults performing a spatial cueing task--to examine both shared and subject-specific aspects of top-down attention. Informative spatial cues elicited sustained activity in fronto-parietal and sensory regions, alpha lateralisation, and increased pupil dilation, replicating established neural and physiological markers. Crucially, these group-level patterns were accompanied by systematic intersubject variability: individuals with greater hearing loss showed increased preparatory engagement of precentral and postcentral gyri, and variation in pupil dilation predicted activity in frontal regions. These results reveal that top-down attention arises from heterogeneous network configurations shaped by sensory processing and strategic resource allocation. Overall, our findings underscore the need to move beyond group averages to capture the neural architecture underlying individual differences in top-down attention.