A neuropsychological perspective on sensory hypersensitivity after acquired brain injury

Individuals with acquired brain injury frequently report a heightened sensitivity to sensory stimuli, commonly referred to as sensory hypersensitivity, which can significantly disrupt daily life and diminish quality of life. Despite a prevalence of up to 83%, the topic of sensory hypersensitivity after acquired brain injury is largely overlooked in existing research. Consequently, the underlying causes and perpetuating factors of sensory hypersensitivity remain poorly understood, hindering the development of effective, evidence-based treatments. In this review, we explore sensory hypersensitivity following acquired brain injury from a neuropsychological standpoint, offering hypotheses regarding the potential neurocognitive and psychological mechanisms involved. Specifically, we propose several hypotheses considering various aspects of sensory processing including, but not limited to, sensory gating, habituation, working memory, processing speed, anxiety, personality, coping and fatigue. These hypotheses are based on acquired brain injury research where possible but also incorporate findings from related fields. Finally, we introduce a conceptual model that explains sensory hypersensitivity as a mismatch between an individual's resources (including the proposed neurocognitive and psychological functions) and the demands imposed by their external sensory environment. We identify several possible mechanisms contributing to sensory hypersensitivity after acquired brain injury and consider a range of factors that may vary per individual. With this review, we aim to establish a foundation for hypothesis-driven research into the causes of sensory hypersensitivity post-injury, by setting a research agenda and supporting the development of psychoeducational and rehabilitative strategies to reduce sensory hypersensitivity and enhance quality of life.