In recent years, scientific interest in sensory processing sensitivity (SPS), a personality trait reflecting increased sensitivity, reactivity, and deeper processing of stimuli, has grown exponentially. Building on this momentum, we synthesise recent SPS literature to discuss several central themes, including SPS assessment, relations to other personality traits and diverse positive and negative outcomes. We propose a novel account of SPS grounded in predictive processing, that bridges cognitive, neural, and computational domains. Specifically, we posit that brains of high-SPS individuals consistently assign high precision to incoming sensory signals. This account offers a unified explanation for the phenotypic consequences of heightened sensory sensitivity. We review behavioural and neural evidence that indirectly supports this account, and delineate important avenues for future research.