Exploring foot-based SNARC effect by hand posture: insights from embodied cognition

Spatial-numerical associations (SNAs), such as the SNARC effect, reflect the tendency to associate smaller numbers with the left side of space and larger numbers with the right. While robust in hand-based tasks, SNAs are flexible and influenced by sensorimotor context. This study examined how static hand posture shapes the SNARC effect in a foot-response paradigm by providing task-irrelevant postural cues, thereby isolating the influence of postural configuration from motor execution. Grounded in embodied cognition, we hypothesized that passive visual and proprioceptive cues would bias spatial-numerical mappings. These cues were provided by task-irrelevant hand postures. Participants (N = 103) completed a magnitude classification task using left and right foot pedals to indicate whether digits (1-4, 6-9) were smaller or larger than 5. Hand posture was manipulated between subjects: fingers interlaced (control), palms down, or palms up. The results revealed significant SNARC effects in the palms-down and palms-up conditions, but not in the control condition, while numerical distance effects were observed across all conditions. These findings indicate that static bodily configurations, even when unrelated to the response effector, can influence SNAs. The results support embodied accounts of numerical cognition, demonstrate that current sensorimotor states influence number-space mappings, and show the methodological utility of foot-based paradigms in disentangling posture effects from response modality.