Abnormal beta power is a hallmark of explicit movement control in functional movement disorders

Teodoro, Tiago; Meppelink, Anne Marthe; Little, Simon; Grant, Robert P.; Nielsen, Glenn; Macerollo, Antonella; Pareés, Isabel; Edwards, Mark J.

doi:10.1212/wnl.0000000000004830

Cited by 14 publications

(30 citation statements)

References 13 publications

(20 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Predictive primes allow a strategic, presumably conscious, preparation for the forthcoming movement. Two previous supraliminal priming studies showed faster reaction times with high cue predictability [95% valid as opposed to non-predictive (50%)] in healthy controls, but slower or unchanged reaction times with high cue predictability in FMD ( 13 , 14 ). That is, whereas predictive supraliminal primes allow healthy volunteers to prepare movements in advance, this process did not operate as normal in FMD patients.…”

Section: Discussionmentioning

confidence: 77%

“…It was similar to the sample size of 20 healthy controls in the agency study with supraliminal priming mentioned below ( 11 ). Furthermore, the sample size was relatively large, compared to previous reaction time studies in FMD with supraliminal premovement cues, which included 8 ( 12 ), 11 ( 13 ), and 21 ( 14 ) FMD patients. Thus, recruitment continued until there were 19 remaining participants in each group.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Modulation of Reaction Times and Sense of Agency via Subliminal Priming in Functional Movement Disorders

et al. 2020

Self Cite

View full text Add to dashboard Cite

Background: In functional movement disorders, explicit movements are impaired, while implicit movements are preserved. Furthermore, there is evidence that the sense of agency is abnormal. Aim: We aimed to investigate how motor responses and sense of agency were affected by subliminal or supraliminal cues in people with functional movement disorders. Methods: Twenty-three people with a functional movement disorder and 26 healthy controls took part in a subliminal and supraliminal priming experiment which investigated reaction times, choice and sense of agency. Participants pressed a left or right arrow key in response to an imperative left or right pointing arrow. Either key could be pressed in response to bidirectional arrows. The imperative arrow was preceded by a small left or right pointing prime arrow, that was non-predictive (50% correct) and was presented in either subliminal or supraliminal conditions. The participant's response caused the appearance of a colored circle and they rated the degree of control they felt over its appearance (sense of agency). The circle's color depended on whether their response was congruent or incongruent with the prime arrow direction. After exclusion, 19 participants remained in each group. Results: Prime-compatible responses led to faster reaction times in both the subliminal and supraliminal condition. Subliminal prime-compatible responses were chosen more frequently in the free choice condition. The sense of agency did not depend on prime-response congruency. There were no significant differences in any of these measures between the two groups. Conclusion: With non-predictive cues, reaction times, choices, and the sense of agency remain normal in people with functional movement disorders, for both subliminal and supraliminal primes. The findings suggest that it is not so much conscious awareness of the movement, but rather conscious motor preparation that is detrimental to motor function in functional movement disorders.

show abstract

Section: Discussionmentioning

confidence: 77%

Section: Methodsmentioning

confidence: 99%

Modulation of Reaction Times and Sense of Agency via Subliminal Priming in Functional Movement Disorders

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Individuals with FMDs are unable to improve motor performance in predictable conditions . This may be related to the finding that those with FMDs demonstrate abnormal maintenance of beta power and failure of beta lateralization on EEG prior to the performance of a motor task, suggesting an impairment in movement prediction . The power in the beta band on EEG normally suppresses and lateralizes before voluntary movement, and these changes are more pronounced when the movement is highly predicted …”

Section: Functional Movement Disordersmentioning

confidence: 99%

Functional Movement Disorders and Placebo: A Brief Review of the Placebo Effect in Movement Disorders and Ethical Considerations for Placebo Therapy

Kaas

Humbyrd

Pantelyat

2018

Movement Disord Clin Pract

View full text Add to dashboard Cite

Background Functional movement disorders are common and disabling neurologic conditions. Patients with functional neurologic disorders represent a large proportion of neurology clinic referrals, and limited availability of subspecialty care creates a considerable burden for the healthcare system. These conditions are currently treated with a combination of physical therapy and cognitive behavioral therapy, with variable success. Methods We searched the Medline database for studies on the epidemiology and physiology of functional movement disorders, as well as those on the placebo effect in movement disorders. We reviewed and summarized the literature on these topics and explored ethical issues concerning the administration of placebos to patients with functional movement disorders. Results Studies of placebos, particularly in patients with movement disorders, have shown that these “inert” agents can provide demonstrable neurophysiologic benefits, even in open‐label studies. Physician surveys have shown that many administer placebos for diagnostic and therapeutic purposes, although there are ethical concerns about this practice. We used a principle‐based approach and reviewed ethical arguments for (justice and beneficence) and against (non‐maleficence and autonomy) the use of placebos in functional movement disorders. In this context, we argue for the importance of the therapeutic alliance in preserving patient autonomy while exploring the potential benefits of placebo therapy. Conclusions An ethical argument is presented in support of nondeceptive clinical placebo use for the treatment of functional movement disorders. Patient and clinician attitudes regarding the use of placebos should be investigated before placebo‐therapy trials are conducted.

show abstract

“…Another element of disordered top‐down control is likely to be abnormal attention to the body part with the involuntary movement. This is apparent clinically, and physiological evidence for this comes from abnormal modulation of beta desynchronization in a choice reaction time task . Patients with functional myoclonus show a Bereitschaftspotential (BP) prior to their involuntary jerks .…”

mentioning

confidence: 99%

“…This is apparent clinically, and physiological evidence for this comes from abnormal modulation of beta desynchronization in a choice reaction time task. 6 Patients with functional myoclonus show a Bereitschaftspotential (BP) prior to their involuntary jerks. 7 The BP was originally described to precede voluntary movement and largely comes from activation of the premotor cortex and supplementary motor area.…”

mentioning

confidence: 99%

Functional movement disorders: Is the crisis resolved?

Hallett

2019

Movement Disorders

View full text Add to dashboard Cite

Abnormal beta power is a hallmark of explicit movement control in functional movement disorders

Cited by 14 publications

References 13 publications

Modulation of Reaction Times and Sense of Agency via Subliminal Priming in Functional Movement Disorders

Modulation of Reaction Times and Sense of Agency via Subliminal Priming in Functional Movement Disorders

Functional Movement Disorders and Placebo: A Brief Review of the Placebo Effect in Movement Disorders and Ethical Considerations for Placebo Therapy

Functional movement disorders: Is the crisis resolved?

Contact Info

Product

Resources

About