Denny-Brown's views on the pathophysiology of dystonia

We review Denny-Brown's hypotheses on the mechanisms underlying motor behav ior and his views on how dysfunction in these mechanisms can result in dyst onia. His formulations were based upon clinical observations of patients wi th diseases of the central nervous system and on monkeys with surgically-in duced lesions of structures affected by diseases in his patients. Denny-Bro wn viewed dystonia as resulting from an imbalance of reflex responses to na tural stimulation, both tonically and phasically. The evidence for this vie w came from demonstration of alterations of dystonic postures by natural ve stibular, cutaneous, proprioceptive and visual stimuli. His formulations re main highly useful to clinicians faced with a bewildering variety of postur al and movement disorders. (C) 1999 Elsevier Science B.V. All rights reserv ed.