Yawn induced limb movements in stroke patients with arm weakness

None listed

For many years the phenomenon of involuntary movements provoked by yawning, has been observed in stroke patients with paralysed limbs, particularly the arm. More than a hundred years ago, an analysis suggested that removal of inhibitory pathways, unmasked the associated movements of yawning and limb movements, which had an evolutionary link related back to the swim bladder and pectoral fins of fish. In healthy individuals, yawning is often accompanied by generalised stretching, which may include elevation of the arms, known as pandiculation. The paralysed arm of stroke patients can be seen to move during a yawn, often bringing the hand towards the mouth, before suddenly dropping again at the end of the yawn. Walusinski coined this, “parakinesia brachialis oscitans”. The observation appears to have been regarded as a curiosity, with some texts almost derisively regarding it as something that could potentially give false hope to stroke patients. There has been some investigation into the neural basis of yawning in healthy subjects, with interest in the possible involvement of the mirror neurone pathways, and other regions distant to the motor cortex, including the ventromedial posterior prefrontal cortex. Movement of the paralysed limb during yawning in patients with pyramidal tract lesions, has been suggested to provide evidence for an independent “emotional motor” system, separate to the corticospinal motor tracts. Recruitment of these areas and pathways might provide a potential mechanism for recovery of motor function after stroke, particularly in the arm. There may thus be some potential for somehow utilising arm movements associated with yawning to stimulate upper limb recovery. Another fascinating aspect of yawning, is the common observation that witnessing yawning in others may result in another individual yawning; so called “contagious” yawning. This does not appear to be related to hypoxia or hypercarbia8. Some 42-55% of humans witnessing images of subjects yawning, will yawn themselves and the act of thinking of yawning may provoke yawning. 33% of adult chimpanzees yawned in response to seeing videos of other chimps yawning, possibly inferring advanced self awareness and empathy in this species. It is possible, therefore that yawning could be “evoked”, and thus used as a potential means for stimulating upper limb movements in paralysed patients. The exciting potential could be that yawning could thus be utilised as a neurorehabilitation therapy The primary purpose of the study is determine the incidence of Yawning Induced Movements in stroke survivors. We hope to use this data to guide the development of future studies with the aim of determining if these movements can have an application in the rehabilitation of stroke survivors

No related papers found yet.