MétaCan
Menu
Back to cohort
Record W3196024575 · doi:10.1016/j.brs.2021.08.013

Variability in motor threshold

2021· letter· en· W3196024575 on OpenAlexaboutno aff
Saxby Pridmore, Renée Morey, Marzena Rybak

Bibliographic record

VenueBrain stimulation · 2021
Typeletter
Languageen
FieldNeuroscience
TopicTranscranial Magnetic Stimulation Studies
Canadian institutionsnot available
Fundersnot available
KeywordsDepression (economics)AnxietyScopusMoodTranscranial magnetic stimulationPsychologyMedicinePsychiatryClinical psychologyInternal medicineMEDLINEStimulation

Abstract

fetched live from OpenAlex

Researchers recently reported a naturalistic retrospective study of motor threshold (MT) data from 374 patients treated with TMS for depression from 2000 to 2019 [[1]Cotovio G. Oliveira-Maia A. Paul C. Viana F. da Silva D. Seybert C. et al.Day-to-day variability in motor threshold during rTMS treatment for depression: clinical implications.Brain Stimul. 2020; 14 (PMID: 34329797): 1118-1125https://doi.org/10.1016/j.brs.2021.07.013Abstract Full Text Full Text PDF Scopus (2) Google Scholar]. MT was measured each day of treatment, “using the visual method”. It is reported that compared to the baseline MT, for each patient, each day, the MT varied (increasing or decreasing) on average more than 5%. It was also stated that “more extreme variations (≥25% above or below the first MT)” could occur. The researchers’ conclusion was that when MT is only determined once, at the commencement of treatment, there is danger of “underdosing” and “overdosing” with potential therapeutic and safety consequences. In consequence the authors suggest “daily or at least weekly MT determination”. The recommended stimulation intensity range is 110–120% MT [[2]Milev R. Giacobbe P. Kennedy S. Blumberger D. Daskalakis Z. Downar J. et al.Canadian network for mood and anxiety treatments (CANMAT) 2016 clinical guidelines for the management of adults with major depressive disorder: section 4. Neurostimulation treatments.Can J Psychiatr. 2016; 61 (PMID: 27486154): 561-575https://doi.org/10.1177/0706743716660033Crossref PubMed Scopus (225) Google Scholar]. However, in blinded studies, successful treatment has been achieved at 80% [[3]George M. Wassermann E. Kimbrell T. Little J. Williams W. Danielson A. et al.Mood improvement following daily left prefrontal repetitive transcranial magnetic stimulation in patients with depression.Am J Psychiatr. 1997; 154 (PMID: 9396958): 1752-1756https://doi.org/10.1176/ajp.154.12.1752Crossref PubMed Scopus (456) Google Scholar], 90% [[4]Pascual-Leone A. Rubio B. Pallardo F. Catala M. Transcranial magnetic stimulation of the left dorsolateral prefrontal cortex in drug-resistant depression.Lancet. 1996; 348 (PMID: 8684201): 233-237https://doi.org/10.1016/s0140-6736(96)01219-6Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar] and 100% [[5]Theleritis C. Sakkas P. Paparrigopoulos T. Vitoratou S. Tzavara C. Bonaccorso S. et al.Two versus one high-frequencyrepetitive transcranial magnetic stimulation session per day for treatment-resistant depression: a randomized sham controlled trial.J ECT. 2017; 33 (PMID: 28445181): 143https://doi.org/10.1097/YCT.0000000000000412Crossref PubMed Scopus (8) Google Scholar] MT. Thus, if treatment is provided in the recommended stimulation intensity range, it is extremely unlikely that the variation in MT could be so great that the stimulation provided (according to the initial MT determination) could be too low to render clinical benefit. At the request of neurosurgeons who were planning to remove epileptic foci, we have attempted to induce seizure (to display foci) in conscious patients using standard therapeutic TMS devices. We have been unsuccessful, having to desist due to patient discomfort before any evidence of seizure activity whatsoever. There is no evidence to indicate that the individual's TMS MT and seizure threshold (should there be one for a particular individual) have a fixed relationship. It is probable they are independent, and the lowering of the MT does not mean there would be a lowering of any TMS seizure threshold. Thus, there is no evidence that variability leading to the lowering of the TMS MT increases the risk of TMS induced seizure. Members of the Clinical TMS Society participated in a survey to clarify the risk of TMS induced seizure [[6]Taylor J. Newberger N. Stern A. Phillips A. Feifel D. Bentensky R. et al.Seizure risk with repetitive TMS: survey results from over half a treatment sessions.Brain Stimul. 2021; 14 (PMID: 34133991): 965-973https://doi.org/10.1016/j.brs.2021.05.012Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar]. The overall rate was 0.31 seizures per 10 000 treatments. For apparatus using generic figure- 8 coils the rates were lower (for example, the Neuronetics device the estimated rate was 0.03 seizures per 10 000 treatments). We accept that during a course of TMS for the treatment of depression, day to day variation in MT of at least 5% (and perhaps more) may occur. However, in our opinion, the risk of inadequate treatment or increased risk of seizure due of this variation is not substantiated. Daily re-determination of MT would be expensive and given the current evidence, unjustified. This work did not receive any specific grand from funding agencies in the public, commercial, or not-for-profit sectors.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.004
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesMeta-epidemiology (narrow)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Not applicable · Consensus signal: Not applicable
GenreCandidate signal: Commentary · Consensus signal: none
Teacher disagreement score0.493
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.004
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0010.000
Bibliometrics0.0000.001
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0010.001
Insufficient payload (model declined to judge)0.0010.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.062
GPT teacher head0.295
Teacher spread0.233 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one teacher head, not a consensus.

Study designNot applicable
Domainnot available
GenreCommentary

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations2
Published2021
Admission routes1
Has abstractyes

Explore more

Same venueBrain stimulationSame topicTranscranial Magnetic Stimulation StudiesFrench-language works237,207