Variability of Head Motion Reveals Development of Spatial Attention

Selective attention, the ability to focus on relevant information while ignoring task-irrelevant information, is crucial for learning. Selective attention has largely been studied in motionless individuals. However, body movements are intrinsic to cognition and particularly frequent in children. To test whether movements explain successful attention control throughout childhood, we tracked head rotations while younger children (6-8 years, n = 25), older children (9-10 years, n = 20) and adults (18-30 years; n = 21) identified a spatial target sound under distraction. Distractor reports decreased with age, confirming a developmental increase in attention control. Importantly, a dissociation of two distinct types of movement emerged: Task-dependent head rotation to lateral targets was similar across age groups. Contrary, task-independent movements before and early during a trial decreased with age and predicted attention accuracy. Thus, movements unrelated to the attention goal do not reflect noise but signify attentional control across development.