RiteeshGrandhi/sciclaimeval-shared-task huggingface dataset:
Conclusions
MS is an immune-mediated neurodegenerative disease characterized by attacks of inflammatory demyelination and axonal damage, with variable but continuous accumulation of disability. Various TMS techniques can characterize conduction loss and axonal damage in the corticospinal tract. Most notably, CMCT could be a putative biomarker to: (1) enhance the specificity of the 2017 McDonald criteria by “ruling-in” true-positive MS diagnoses, (2) revise a diagnosis from RMS to PPMS, or (3) help arrive at an earlier diagnosis of SPMS. Herein, the authors summarized the current state of the literature and determined both a high risk of bias and poor justification for the validity of TMS techniques as diagnostic biomarkers in MS. In the future, more rigorous, prospective, longitudinal studies will be required, using comparisons to the 2017 McDonald criteria.
Figure 1: Simplified schematic of transcranial magnetic stimulation (TMS)-induced generation of motor evoked potential (MEP).
(A) Pulse generator produces an electric current that is stored in, and rapidly discharged from, a large capacitor into the stimulating coil. (B) The insulated coil contains windings of copper, which generate a focal magnetic field from the electric current. (C) The magnetic field undergoes little attenuation from extracerebral tissues and painlessly induces an electric current in underlying layer II/III/V pyramidal neuron axons at the gyral crown of the primary motor cortex. (D) Activation of corticospinal pyramidal neurons elicits descending corticospinal volleys from the brain to the spinal cord by directly activating pyramidal tract neurons, or indirectly via interneurons that synapse onto the pyramidal tract/lateral corticospinal tract. (E) The descending corticospinal volley activates the target muscle, via stimulation of anterior horn cells, peripheral nerve, and motor unit. (F) The TMS-induces motor evoked potential (MEP) can be recorded via electromyography (EMG), with recording electrodes placed over the belly of the target muscle. (G) Analyzing the amplitude, latency, duration, and waveform characteristics provides information on the excitability and conduction characteristics of corticospinal pyramidal cells; the post-MEP corticospinal silent period (CSP) characterizes the excitability of corticospinal inhibitory interneurons. See refs: (Chaves et al., 2021; Rossini et al., 2015; Siebner et al., 2022; Snow et al., 2019; Spampinato et al., 2023) .

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DOI: 10.7717/peerj.17155/fig-1
Figure 2: Flow chart of study selection.
EP, evoked potential; MS, multiple sclerosis; TES, transcranial electrical stimulation; TMS, transcranial magnetic stimulation (Page et al., 2021).

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DOI: 10.7717/peerj.17155/fig-2
Figure 3: Forest plot of diagnostic odds ratio (DOR) for transcranial magnetic stimulation (TMS)-based outcomes.
Demonstrates DOR point estimates and 95% confidence intervals studies, coded by risk of bias (* or green = Low, † or yellow = Unclear, ‡ or red = High). CMCT, central motor conduction time; CSP, corticospinal silent period; iSP, ipsilateral silent period; MEP, motor evoked potential; MS −, negative diagnosis of multiple sclerosis; MS +, positive diagnosis of multiple sclerosis; RMT, resting motor threshold; TCT, transcallosal conduction time; TST, triple stimulation technique. Note, for studies reporting multiple DORs, only the highest value is reported (Cruz-Martínez et al., 2000; Hess et al., 1987; Mayr et al., 1991; Ravnborg et al., 1992; Schmierer et al., 2000; Tataroglu et al., 2003; Beer, Rösler & Hess, 1995; Magistris et al., 1999).

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DOI: 10.7717/peerj.17155/fig-3
Description of transcranial magnetic stimulation (TMS) outcomes.
Sample 2 × 2 contingency table.
Multiple sclerosis (MS) participant characteristics.
Transcranial magnetic stimulation (TMS) results.
Risk of bias assessment.
Biomarker assessment.