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Bringing order to higher order motor disorders

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Abstract

Majority of movements in everyday situations are complex and involve volition, planning of the movement and selection of the motor programme, all occurring before movement execution. Higher order motor disorders may be defined as abnormal motor behaviours resulting from disruption of any of the cortical processes that precede execution of the motor act. They are common in patients with neurodegenerative disorders, psychiatric diseases and structural brain lesions. These abnormal behaviours may be overlooked in the clinic, unless specifically evoked by the examiner. We discuss clinical and pathophysiological aspects of higher order motor disorders including: (1) disorders of disinhibition, such as grasp reflex and grasping behaviour, utilisation and imitation behaviour, motor preservations and paratonia; (2) disorders of motor intention such as motor neglect and motor impersistence; (3) alien limb syndrome; and (4) motor overflow phenomena, such as mirror movements and synkinesias. A video illustration of each phenomenon is provided. We place the findings from recent neurophysiological studies within the framework of theories of motor control to provide better insight into pathophysiology of different disorders.

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Authors and Affiliations

  1. Department of Neurology, University Medical Centre Ljubljana, Zaloška 2, 1000, Ljubljana, Slovenia

    Maja Kojović

  2. Institute of Neurology, University College London, 7 Queen Square, London, WC1N 3BG, UK

    Kailash P. Bhatia

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  1. Maja Kojović
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  2. Kailash P. Bhatia
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Correspondence to Maja Kojović.

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The manuscript does not contain clinical studies. All patients gave their informed consent for video recording and publication in clinical/scientific journal.

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The authors declare that they have no conflict of interest.

Ethical standards

The study has been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki.

Electronic supplementary material

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Video 1. Grasping reflex. Grasping is present on both side and consists of forced hand closure over the hammer’s handle. After instructed not to grasp, patient resisted it, showing grasping is not absolutely forced phenomenon. (WMV 6291 KB)

Video 2: Prehension (grasping) behaviour. Patient with corticobasal syndrome follows with hands an object presented as tactile and visual stimulus, in an attempt to seize it. This behaviour is spontaneous and occurs while examiner is talking to patient’s spouse. The patient did not get any instructions. (MP4 76813 KB)

Video 3. Utilisation behaviour. Various objects were put in front of the patient with frontal lobe tumour, without giving him any instructions. The patient first uses neurological hammer, he then put on the gloves on and finally starts eating cookies. When doctors asked him why he put the gloves on, he had no answer. (WMV 35525 KB)

Video 4. Motor preservations (continuous). Patient with progressive supranuclear palsy and positive applause sign. He was asked to clap three times after demonstration by the examiner; however, he clasped many times. (MP4 2047 KB)

Video 5. Paratonia. Despite repeated suggestion by examiner, the patient is not able to relax during examination of the muscle tone. Limb stay lifted up in the air after quick release by examiner. (MP4 17879 KB)

Video 6. Facilitatory paratonia. Patient with early Alzheimer dementia actively assists the passive movements. When the arm is released, it becomes obvious that patient is making the same active movements as were the passive movements made by examiner. (WMV 18760 KB)

Video 7. Motor neglect. The patient has right frontoparietal metastasis. It can be noticed that he shaved only the right half of the face. On instruction to lift the arms up, he lifts only the right arm. On explicit instruction to lift both arms up, he is able to do it. On instruction to put arms down, he release only the right arm, while he still keep holding the handle with his left arm. Finally, he puts the left arm down after directly prompted by examiner. (WMV 10650 KB)

Video 8. Motor extinction. During bimanual movements, the performance of the left, affected limb, is deteriorating until it finally stops moving. (WMV 2666 KB)

Video 9. Motor neglect in right SMA lesion. The patient underwent surgery for right SMA cortical dysplasia (as treatment for pharmaco-resistant epilepsy) and suffered postoperative oedema. Few days following surgery, she could not move the left leg on command (both supine and when sitting), although she could walk almost normally. Patient was completely aware of the problem, which remitted after 2 weeks. (WMV 32432 KB)

Video 10. Gaze impersistence. Patient is unable to keep eyes fixated to the target, particularly on leftward gaze, with eyes constantly drifting toward midline. When looking up, eyes drift down, in ping-pong fashion. (WMV 30283 KB)

Video 11. Frontal alien hand syndrome. Patient with corticobasal syndrome magnetically follows an object with dominant hand only and finally forcefully grasp it. (WMV 14033 KB)

Video 12. Patient with parietal lobe stroke complained his right arm was spontaneously lifting and he felt it as not being his arm. Right arm spontaneously slowly levitates (both with eyes open and closed). (MP4 15520 KB)

Video 13. Alien hand in corticobasal syndrome. Left arm manifest non-purposeful movements, while right arm is held in abnormal posture and patient does not utilise it (useless hand). (MP4 13647 KB)

Video 14. Alien leg. Patient with corticobasal syndrome manifest spontaneous levitation of the left leg that may last for hours. She has patellar dislocation due to these prolonged abnormal postures. (MP4 57807 KB)

Video 15. Useless hand. Left arm is held in an abnormal flexed posture and the patient does not use it, apart for stereotyped nose pocking. The patient also uses his left arm as a support when standing up, suggesting that automatic movements are preserved. (WMV 70494 KB)

Video 16. The patient with cerebral palsy and right hemiparesis shows mirror movements when moving both, affected and non-affected arm (see also Figure 2). (MP4 21964 KB)

Video 17. Patient with Parkinson’s disease shows mirror movements when finger tapping with the more affected (right side), while no mirror movements are seen when moving less affected side. (MP4 37534 KB)

Video 18. Mirror movements in patient with corticobasal syndrome. On attempt to imitate meaningless gestures with right (more affected side), MM are seen on the opposite side. (WMV 12916 KB)

Video 19. Mirror movements in proximal joints. Mirroring appears in the right elbow joint, when the patient performs finger to nose test with left arm. (WMV 3408 KB)

Video 20. When the patient intentionally open and close the left fist, synkinesias (synchronous involuntary movements of the same direction and speed) appear in both legs. (MP4 19058 KB)

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Kojović, M., Bhatia, K.P. Bringing order to higher order motor disorders. J Neurol 266, 797–805 (2019). https://doi.org/10.1007/s00415-018-8974-9

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