Attention focus modulates motor performance and frontoparietal connectivity: an fNIRS study.

Attentional focus strategies are critical for optimizing motor performance, with extensive evidence suggesting that an external focus promotes movement automaticity while an internal focus induces conscious constraint. However, the underlying neural mechanisms, specifically the cortical dynamics and network connectivity patterns that differentiate these strategies remain largely unexplored.This study examined the impact of different attentional foci on performance and cortical activity during isometric knee extension exercises. Twenty-eight healthy college students participated, performing isometric knee extensions under three attentional strategies: purposeless, external focus (EF), and internal focus (IF). During these exercises, activity in the prefrontal cortex, sensorimotor cortex, and posterior parietal cortex was monitored using functional near-infrared spectroscopic imaging (fNIRS). Granger causality(GC) analysis assessed effective connectivity among brain regions. Behavioral results indicated that peak torque, work per repetition, and average power per repetition were significantly higher with EF strategies compared to IF strategies across all trials. Additionally, under the EF condition, participants achieved greater peak torque and reached it more quickly than under the purposeless conditions and IF conditions. fNIRS findings revealed increased oxyhemoglobin levels in the bilateral primary sensorimotor cortex(PSMC) and bilateral somatosensory association cortex(SAC) with EF strategies. Furthermore, extensive effective connections were observed among the brain regions of interest under EF strategies. GC coefficients were notably higher from the left prefrontal cortex (PFC)to the right PFC and left SAC under EF strategies compared to IF and purposeless strategies. Additionally, the data reveal a positive correlation between the increased work done per repetition under EF strategies, and the rise in oxy-Hb in the left PFC. This study demonstrates that the external focus of attention EF strategy can more effectively enhance motor performance and increase the activity of the frontal lobe and parietal lobe areas. The focus of attention may affect the efficiency of motor execution by regulating the functional connections of the prefrontal and parietal networks.