The body’s automatic responses to adjust balance and maintain equilibrium. This reflex depends upon inputs from the vestibular system (inner ears), cerebellum, sensory system (proprioception), and even vision. It is fundamental to the ability to sit, stand, and walk or engage in any movement of mobility. In Parkinson’s disease, failure of the postural righting reflex results from the loss of dopaminergic neurons and nigrostriatal fibers that reduces the availability of dopamine. Motor areas of the brain can no longer function, creating breaches in the reflex pathways. It is possible to train other parts of the brain to take over the functions of the postural righting reflex, and during the early and mid stages of Parkinson’s the person often can overcome postural righting reflex inadequacies through conscious reaction and response. However, the progressive deterioration of Parkinson’s makes this a difficult and ultimately unsuccessful challenge by the disease’s later stages. See also body scheme; gait; gait disturbance; postural instability; proprioception; walking.