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Trial registered on ANZCTR

Registration number
Ethics application status
Not yet submitted
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Yawn induced limb movements in stroke patients with arm weakness
Scientific title
Establishing the neuro-anatomical basis for extrapyramidal yawning movements observed in stroke patients with arm weakness
Secondary ID [1] 283480 0
Universal Trial Number (UTN)
Trial acronym
Yawning Induced Movements in Stroke Study ( YIMSS)
Linked study record

Health condition
Health condition(s) or problem(s) studied:
290398 0
Yawning Induced Movements in an otherwise paralysed limb 290604 0
Condition category
Condition code
Neurological 290789 290789 0 0
Other neurological disorders
Stroke 290994 290994 0 0

Study type
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Observation Study:
1. Observe incidence of YIMS (yawning induced movements in stroke survivors) - subjects will be asked to complete regular surveys noting how frequently they observed autonomous movements associated with yawning.
2. Clinical survey upon admission to tertiary hospital for stroke for up to 6 months following a first stroke
3. Subjects will complete a survey upon admission and at 2 weeks, 1 and 3 and 6 months to determine their individual functional level and incidence of yawning induced movements
4. Subjects will be given a survey kit with the two week and 1,3 and 6 month survey forms, information pack and return prepaid envelopes
5. Investigators provide a reminder phone call prior to each survey to improve adherence
6.As secondary aim, wish to compare neuroanatomical stroke lesions between patients with YIMs against those without YIMs. Identifying these lesions will involve going through Head imaging taken during the diagnosis of stoke and potential fMRI in future studies
Intervention code [1] 288191 0
Not applicable
Comparator / control treatment
N/A - This is an observational study
Control group

Primary outcome [1] 290784 0
1. Determine Incidence of Yawning Induced Arm Movements in stroke survivors
Incidence will be determined by participant observation and recollection.
Timepoint [1] 290784 0
At admission and at 2 weeks, 1 month, 3 months and 6 months
Secondary outcome [1] 305284 0
1. Establish (if possible) neuroanatomical correlations between subjects with YIMs compared to subjects without YIMs
This will be assessed through comparison of head imaging done at time of diagnosis and possibly fMRI as a separate study in the future
Timepoint [1] 305284 0
1. Secondary time point for each patient is 6 months

Key inclusion criteria
Age >18
Cerebrovascular Accident (aka Stroke) presenting in 3-13 days
Stroke associated with motor deficit (paralysis) of the upper limbs
Able to give consent/assent
Family member able to give assent on behalf of patient
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Severe stroke or co-morbidities that make early death more likely
Previous Stroke
Significant movement disorders ( Parkinson’s Disease, Multiple Sclerosis, Motor Neuron Disease)

Study design
Natural history
Defined population
Statistical methods / analysis
Predicted sample size of 200-300 subjects

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 1634 0
Sir Charles Gairdner Hospital - Nedlands
Recruitment postcode(s) [1] 7521 0
6009 - Nedlands

Funding & Sponsors
Funding source category [1] 288186 0
Self funded/Unfunded
Name [1] 288186 0
Address [1] 288186 0
Country [1] 288186 0
Primary sponsor type
Dr Benjamin Mulo
Sir Charles Gairdner Hospital
Department of Neurology
Hospital Avenue
Nedlands 6009
Western Australia, Australia
Secondary sponsor category [1] 286911 0
Name [1] 286911 0
Address [1] 286911 0
Country [1] 286911 0
Other collaborator category [1] 277673 0
Name [1] 277673 0
Address [1] 277673 0
Country [1] 277673 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 290096 0
SCGH Human Ethics Research Committee
Ethics committee address [1] 290096 0
Sir Charles Gairdner Hospital
Hospital Avenue
Nedlands 6009
Western Australia
Ethics committee country [1] 290096 0
Date submitted for ethics approval [1] 290096 0
Approval date [1] 290096 0
Ethics approval number [1] 290096 0

Brief summary
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
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 43950 0
A/Prof David Blacker
Address 43950 0
Department of Neurology
Sir Charles Gairdner Hospital
Hospital Avenue
Nedlands 6009
Western Australia
Country 43950 0
Phone 43950 0
+61 8 9346 3333
Fax 43950 0
Email 43950 0
Contact person for public queries
Name 43951 0
Dr Benjamin Mulo
Address 43951 0
Department of Neurology
Sir Charles Gairdner Hospital
Hospital Avenue
Nedlands 6009
Western Australia
Country 43951 0
Phone 43951 0
+61 8 9346 3333
Fax 43951 0
Email 43951 0
Contact person for scientific queries
Name 43952 0
Dr Benjamin Mulo
Address 43952 0
Department of Neurology
Sir Charles Gairdner Hospital
Hospital Avenue
Nedlands 6009
Western Australia
Country 43952 0
Phone 43952 0
+61 8 9346 3333
Fax 43952 0
Email 43952 0

No information has been provided regarding IPD availability
Summary results
No Results