Brain’s neural activities encompass both periodic rhythmic oscillations and aperiodic neural fluctuations. Among them, rhythmic oscillations manifest as spectral peaks of neural signals, directly reflecting the synchronized activities of the brain neural population and being intimately tied to cognitive and behavioral states. Conversely, aperiodic fluctuations exhibit a power-law decaying spectral trend, unveiling the multiscale dynamics of brain neural activity. In recent years, researchers have made notable progress in the study of brain aperiodic dynamics. These studies demonstrate that aperiodic activity bears significant physiological relevance, correlating with various physiological states such as external stimuli, drug induction, sleep states, and aging. It serves as a reflection of the brain’s sensory capacity, consciousness level, and cognitive ability. In clinical research, the aperiodic exponent emerges as a significant potential biomarker, capable of reflecting the progression and trends of brain diseases while being intricately intertwined with the excitation-inhibition balance of neural system. The physiological mechanisms underlying aperiodic dynamics span multiple neural scales, with neural activities at the levels of individual neurons, neuronal ensembles, and neural networks each expletively influencing the frequency, oscillatory patterns, and spatiotemporal characteristics of aperiodic activities. Currently, aperiodic dynamics boasts broad application prospects, not only providing a fresh perspective for investigating brain neural dynamics but also holding immense potential as neural markers in neuromodulation technologies or brain-computer interface technologies. This paper summarizes methods for extracting characteristic parameters of aperiodic activity, comparatively analyzes its physiological relevance and potential as a biomarker in brain diseases, summarizes its physiological mechanisms, and finally, based on these findings, elaborates on the research prospects of aperiodic dynamics.