Interindividual differences in auditory processing moderate the effect of auditory-motor coupling on paired-associate learning.

The present study explored the effects of auditory-motor coupling and individual differences in pitch perception on verbal learning. Participants (N = 47) learned a list of foreign-language vocabulary word pairs under isochronous or self-initiated auditory stimulation while cycling on a stationary bike. As expected, better movement consistency-i.e., lower cycling variability and more stable synchronization with the vocabulary presentation-was weakly associated with improved memory performance. Interestingly, we found inter-individual differences in the pattern of results: participants with fundamental pitch perception (FPP) benefited from isochronous stimulation immediately after learning (Day 1), but not after overnight consolidation (Day 2), whereas participants with spectral pitch perception (SPP) showed a long-term memory benefit from isochronous stimulation. This suggests that auditory processing characteristics modulate whether isochronous input supports early encoding or later consolidation. Furthermore, musically experienced participants showed more variable pedaling in the self-initiated condition, possibly reflecting deliberate modulation of input timing. In contrast, isochronous stimulation reduced variability across all participants, indicating implicit synchronization even without an explicit instruction to synchronize. Overall, these findings highlight the role of individual auditory and motor traits in shaping the cognitive benefits of sensorimotor coupling during learning.