The predictive basis of intensity and loudness processing

Our brains' predictions dramatically affect what we perceive, including how strongly we feel physical sensations (i.e. their intensity), with a common example being placebo analgesia. Furthermore, many clinical disorders of sensation (including tinnitus, hyperacusis, chronic pain and fibromyalgia) may have anomalies of predictive intensity processing at their heart. However, little is known about predictive processing of intensity, compared to other aspects of perception. Here, I propose to systematically study, in human volunteers, the brain mechanisms underlying predictive processing of intensity, mainly in the auditory system but also in tactile sensation, across a range of scales from local neural circuits to brain-wide connections, and in both normal functioning and a limited range of clinical disorders of sensation. Outcomes will be a coherent understanding of the normal functioning of these systems in the brain, with methods and knowledge immediately transferrable to the study, understanding, diagnosis and treatment of common disorders of sensation.