Persistent Postural Perceptual Dizziness (also called Chronic Subjective Dizziness)
PPPD (Persistent Postural Perceptual Dizziness) refers to constant sense of imbalance or dizziness that is worse with motion and visual stimuli. It commonly occurs after an inciting event, such as vestibular neuritis or BPPV, leading some to conjecture that PPPD reflects a central maladaptation to the inciting event in susceptible individuals (anxiety, depression, and obsessive-compulsive personality are all common with PPPD). Diagnosis is made after a thorough evaluation and workup to make sure that other causes of dizziness are not present. Treatment involves medications (typically SSRIs or SNRIs), vestibular physical therapy, and treatment of co-existing conditions that may be contributing to symptoms. Since patients with PPPD seem to be overly 
“sensitized” to motion, part of the therapy is aimed at “habituation”, or getting the patient used to regular motion by repeated exposure in a safe environment.