Rhythm Cycle Alignment Task (RCAT). Cross-Cultural Differences in Aligning to Long Rhythmic Cycles from North Indian Classical Music.

Long rhythmic cycles (‘tal’) are a defining feature of North Indian Classical Music (NICM),yet their perceptual processing remains largely unexplored in empirical research. These cyclescommonly extend up to 16 beats and last more than 3 seconds, placing substantial demands onmemory capacity. Identifying the first beat is critical for understanding any NICM rhythmcycle, as it serves as the structural anchor for rhythmic organisation. How listeners perceiveand locate this first beat remains an open question in rhythm cognition, particularly in cross-cultural contexts where rhythmic structures and enculturated listening strategies differ. Thisstudy introduces a novel rhythm cycle alignment task to examine how cultural familiarity andmusical training shape the ability to identify the first beat of long NICM rhythmic cycles.Participants were required to align a tone track (beeps) with a continuously looping rhythmiccycle in real time, adjusting its position to indicate where they perceived the cycle to begin.Four NICM rhythm cycles were tested (7-beat Rupaktal, 8-beat Kehervatal, 10-beat Jhaptal,and 16-beat Teental). The study included four participant groups (N = 121): Culturally FamiliarNICM Musicians, Culturally Familiar (Indian) Non-musicians, Culturally Unfamiliar WesternMusicians, and Culturally Unfamiliar Western Non-musicians. Results showed that NICMmusicians accurately aligned the first beat across all rhythm cycles, demonstrating robust top-down processing. Western musicians performed above chance only for isochronous cycles,suggesting reliance on temporal regularities common in Western music. Neither Indian norWestern non-musicians aligned the first beat above chance. To examine bottom-up strategies,alignment responses were compared with acoustic templates derived from the rhythmic stimuli.For all groups except NICM musicians, responses were best predicted by weak-to-strongtimbral transitions, indicating a reliance on local acoustic salience rather than cycle-levelstructure.Overall, the study presents a replicable method for measuring rhythm-cycle perception anddemonstrates that the accurate identification of the first beat in long NICM cycles is culture-specific and dependent on musical training.