A novel exaggerated "spino-bulbo-spinal like" reflex of lower brainstem origin

Parkinsonism Relat Disord. 2019 Apr;61:34-38. doi: 10.1016/j.parkreldis.2018.10.007. Epub 2018 Oct 6.


Background: Many different oligosynaptic reflexes are known to originate in the lower brainstem which share phenomenological and neurophysiological similarities.

Objective: To evaluate and discuss the differences and aberrancies among these reflexes, which are hard to discern clinically using neurophysiological investigations with the help of a case report.

Methods: We describe the clinical and neurophysiological assessment of a young man who had a childhood history of opsoclonus-myoclonus syndrome with residual mild ataxia and myoclonic jerks in the distal extremities presenting with subacute onset total body jerks sensitive to sound and touch (in a limited dermatomal distribution), refractory to medications.

Results: Based on clinical characteristics and insights gained from neurophysiological testing we could identify a novel reflex of caudal brainstem origin.

Conclusions: The reflex described is likely an exaggerated normal reflex, likely triggered by a dolichoectatic vertebral arterial compression and shares characteristics of different reflexes known to originate in caudal brainstem, which subserve distinctive roles in human postural control.

Keywords: Jerk-like movements; Myoclonus; Physiology; Reflex; Startle.

Publication types

  • Case Reports
  • Research Support, N.I.H., Intramural
  • Video-Audio Media

MeSH terms

  • Acoustic Stimulation
  • Adult
  • Ataxia / etiology
  • Brain Stem / diagnostic imaging
  • Brain Stem / physiopathology*
  • Cognitive Dysfunction / etiology
  • Electromyography
  • Humans
  • Male
  • Myoclonus / etiology
  • Opsoclonus-Myoclonus Syndrome / complications
  • Physical Stimulation
  • Reflex, Abnormal / physiology*
  • Reflex, Startle / physiology*
  • Touch
  • Vertebral Artery
  • Vertebrobasilar Insufficiency / complications
  • Vertebrobasilar Insufficiency / diagnostic imaging
  • Vertebrobasilar Insufficiency / physiopathology*