The paper entitled The neurobiology of altered states of consciousness induced by drumming and other rhythmic sound patterns, by Aparicio-Terrés, R., López-Mochales, S., Díaz-Andreu, M., & Escera, C. (2025), has been published in the journal Annals of the New York Academy of Sciences.

Rhythm is a universal force that shapes our minds and bodies, guiding us from moments of quiet rest to collective exhilaration. Whether it is a mother gently rocking her baby to sleep, or a crowd moving as one to the pulse of a dance beat, rhythm exerts a powerful influence on us.

While rhythmic energy can enter the brain through many channels (auditory, vestibular, tactile, or visual) it is auditory rhythm that has become especially central in cultural practices designed to alter consciousness. Unlike other sensory inputs, sound requires no direct contact and can reach individuals across space, making it a particularly accessible and scalable medium for shared experience. This raises an important question: what is it about sound, particularly in its rhythmic structure, that makes it so effective in shaping our state of consciousness?

In this review paper we synthesize the behavioral, cognitive, and neural evidence behind altered states of consciousness elicited by rhythmic auditory stimulation, including drumming, binaural beats, chanting and mantras. The reviewed literature reveals a consistent link between exposure to these rhythmic sounds and absorption and relaxation, even in participants with no prior understanding of altered mental states.

Figure 1. Flowchart illustrating the proposed framework linking rhythmic auditory stimulation to altered states of consciousness. We suggest that practices involving rhythmic sound, such as drumming, binaural beats, and chanting, may induce ASCs through entrainment of thalamo-cortical low-frequency oscillations.

At the neural level, findings are diverse but align on a promising mechanistic proposal: entrainment of thalamo-cortical networks to low-frequency rhythmic input. This pattern of neural synchronization overlaps with physiological states observed in both psychosis and psychedelic experiences, suggesting a shared brain-state architecture that might underlie these otherwise distinct forms of non-ordinary consciousness.

Figure 2. Representation of the proposed neural pathways linking rhythmic auditory stimulation to altered states of consciousness. Both lemniscal and non-lemniscal projections from the medial geniculate body transmit information through the thalamo-cortical network to higher-order cortical regions. These pathways may become entrained to external auditory rhythms, potentially linking repetitive sounds to changes in arousal, emotion, and behavioral states.

Following this theoretical proposal, we launched an experimental study to evaluate its validity, which led to another recently published paper (Aparicio-Tarrés et al., 2025, Front Human Neurosci. We used non-invasive electroencephalography to assess how rhythm-induced altered states relate to brainwave entrainment to the rhythmic sounds. We demonstrated that electronic music with a four-on-the-floor beat can modulate brainwave entrainment and subjective experiences of unity. We also found that the strength of entrainment was related to proxies of altered states of consciousness, although the underlying mechanisms are complex and require further investigation.

This research was conducted as part of the ERC Artsoundscapes project, an interdisciplinary initiative that investigated how sound shaped sacred experiences in ancient societies. Although the project is now concluded, we anticipate sharing additional findings in upcoming publications, contributing to the broader understanding achieved through this unique collaborative effort.

The full abstract reads as follows:

Humans have long sought to alter their mental states through various cultural practices, with rhythmic sounds emerging as a prominent and enduring method.

However, altered states of consciousness induced by rhythmic auditory stimulation have not been comprehensively addressed in academic research, and the associated cognitive and neural underpinnings remain enigmatic. This narrative review synthesizes the behavioral, cognitive, and neural correlates underlying non-ordinary experiences elicited by rhythmic sounds. The evidence gathered aligns with the notion that being exposed to these sounds facilitates a state of absorption and relaxation. The findings on the neural activity were diverse, reflecting the use of various methodologies in the reviewed studies. We discussed that altered states induced by rhythmic sounds may be explained by a mechanism involving the entrainment of thalamo-cortical pathways to low-frequency activity—a physiological state that also characterizes psychotic and psychedelic experiences. This proposal integrates insights from diverse findings, which reflect the variability in methodologies used to address these phenomena.

Reference:

Aparicio-Terrés, R., López-Mochales, S., Díaz-Andreu, M., & Escera, C. (2025). The neurobiology of altered states of consciousness induced by drumming and other rhythmic sound patterns. Annals of the New York Academy of Sciences, in press.Permanent doi: pending