Development and vibration transmissibility analysis of a biofidelic human brain model

Vibrations can have harmful effects on the human brain and are associated with neurological damage, cognitive impairments, and an increased risk of traumatic brain injuries (TBI). Exposure to low-frequency vibrations, such as those encountered in blast events, contact sports, and accidents, can induce resonance within the brain, potentially amplifying mechanical stress and strain on neural structures. To better understand these effects, this study examines the mechanical response of a cerebrum-shaped human brain simulant subjected to vertical vibrations within the 1-12 Hz frequency range. Using a full-scale biofidelic brain model fabricated from a multi-part polymeric material, experimental measurements and a simplified mathematical model were employed to analyse vibration transmissibility characteristics. The first resonance peak was observed between 4-4.2 Hz, aligning with previously reported frequency ranges. Regional variations in transmissibility were observed within the experimental model, with relatively higher transmissibility in the temporal region at approximately 8 Hz, while the left and right hemispheric regions exhibited resonance peaks at 2, 9, and 11 Hz, along with an intermediate anti-resonance feature. The absence of surrounding anatomical structures, such as the skull and cerebrospinal fluid, may contribute to the observed transmissibility levels. These findings provide baseline experimental data on the vibration response of a developed biofidelic brain model and contribute to the understanding of vibration transmissibility behavior in controlled laboratory settings. The developed model offers a repeatable experimental platform that may support future investigations into brain vibration dynamics and the progressive development of more anatomically and mechanically representative models for safety and injury biomechanics research.