Distance-adjusted motor threshold for transcranial magnetic stimulation

Stokes, Mark G.; Chambers, Chris; Gould, Ian C.; English, Therese; McNaught, Elizabeth; McDonald, Odette; Mattingley, Jason B.

doi:10.1016/j.clinph.2007.04.004

Cited by 191 publications

(131 citation statements)

References 37 publications

Supporting

Mentioning

122

Contrasting

Unclassified

Order By: Relevance

“…For rIFG and rIFJ, the coil was positioned with the handle in an upward vertical orientation, whereas for preSMA, it was oriented with the handle in a posterior direction. The output intensity was calibrated according to the maximum level of comfortable stimulation, expressed as a proportion of resting motor threshold (average = 51.5% of maximum stimulator output), and corrected for differences in scalp-cortex distance between brain regions (55,56). This protocol yielded an average stimulation output of 70% distance-adjusted motor threshold (range 51-80%) and an average stimulator output of 30% (range 20-39%).…”

Section: Methodsmentioning

confidence: 99%

Theta burst stimulation dissociates attention and action updating in human inferior frontal cortex

Verbruggen

Aron

Stevens

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

284

278

View full text Add to dashboard Cite

Everyday circumstances require ef␣cient updating of behavior. Brain systems in the right inferior frontal cortex have been identi␣ed as critical for some aspects of behavioral updating, such as stopping actions. However, the precise role of these neural systems is con- troversial. Here we examined how the inferior frontal cortex updates behavior by combining reversible cortical interference (transcranial magnetic stimulation) with an experimental task that measures different types of updating. We found that the right inferior frontal cortex can be functionally segregated into two subregions: a dorsal region, which is critical for visual detection of changes in the environment, and a ventral region, which updates the corresponding action plan. This dissociation reconciles competing accounts of pre- frontal organization and casts light on the neural architecture of human cognitive control

show abstract

Section: Methodsmentioning

confidence: 99%

Theta burst stimulation dissociates attention and action updating in human inferior frontal cortex

Verbruggen

Aron

Stevens

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

284

278

View full text Add to dashboard Cite

show abstract

“…33 Thus, to adjust for coil-to-cortex distance, stimu lation was delivered at 120% of the distance-adjusted RMT (AdjRMT) according to the equation AdjRMT = RMT + 2.8 × (D DLPFC -D M1 ), where AdjRMT is the adjusted RMT in % stimulator output, RMT is the unadjusted RMT in % stimulator output, D M1 is the distance between the scalp and the motor cortex (M1), and D DLPFC is the distance between the scalp and DLPFC. 32 In order to localize the DLPFC stimulation site, a structural MRI (parameters: high-resolution, T 1 -weighted, 128 slices, repetition time [TR] 9.08 ms, echo time [TE] 2.70 ms, matrix size 256 × 256, slice thickness 1.40 mm, 1.5 T Signa General Electric scanner) was coregistered to participants' heads using a magnetic tracking device (miniBIRD, Ascension Technology Group) for coil-to-cortex coregistration. The targeted stimulation site for the DLPFC was an area between the centre of Brodmann area (BA) 9 and the border of BA 9 and 46, based on the conservative definition of these areas in previous research.…”

Section: Rtms Treatment and Neuronavigationmentioning

confidence: 99%

“…30,31 Unadjusted stimulation J Psychiatry Neurosci 2016;41(4) may lead to both understimulation and overstimulation depending on the coil-to-cortex distance. 32 Greater coil-to-cortex distance has been associated with reduced efficacy of therapeutic TMS. 33 Thus, to adjust for coil-to-cortex distance, stimu lation was delivered at 120% of the distance-adjusted RMT (AdjRMT) according to the equation AdjRMT = RMT + 2.8 × (D DLPFC -D M1 ), where AdjRMT is the adjusted RMT in % stimulator output, RMT is the unadjusted RMT in % stimulator output, D M1 is the distance between the scalp and the motor cortex (M1), and D DLPFC is the distance between the scalp and DLPFC.…”

Section: Rtms Treatment and Neuronavigationmentioning

confidence: 99%

Unilateral and bilateral MRI-targeted repetitive transcranial magnetic stimulation for treatment-resistant depression: a randomized controlled study

Blumberger

Maller

Thomson

et al. 2016

jpn

View full text Add to dashboard Cite

“…In order to distinguish between these two possibilities, individual structural magnetic resonance imaging scans co-localised to neuronavigated TMS would be required to establish scalp-cortex distance (see Stokes et al, 2007).…”

Section: Sici Is Increased In Elderly Participants With Ap Coil Orienmentioning

confidence: 99%

Increased intracortical inhibition in elderly adults with anterior–posterior current flow: A TMS study

Sale

Lavender

Opie

et al. 2016

Clinical Neurophysiology

View full text Add to dashboard Cite

Please cite this article as: Sale, M.V., Lavender, A.P., Opie, G.M., Nordstrom, M.A., Semmler, J.G., Increased intracortical inhibition in elderly adults with anterior-posterior current flow: a TMS study, Clinical Neurophysiology (2015), doi: http://dx.doi.org/10. 1016/j.clinph.2015.04.062 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Increased intracortical inhibition in elderly adults Highlights• We show no age-related difference in intracortical inhibition using a conventional (posterior-anterior) transcranial magnetic stimulation (TMS) coil orientation.• Using the more sensitive (anterior-posterior) TMS coil orientation, we show increased intracortical inhibition in older adults.• Reversing TMS current direction could be helpful to assess subtle differences in intracortical inhibition in clinical populations. AbstractObjective: All previous studies using TMS to assess short-interval intracortical inhibition (SICI) in older adults have used a conventional coil orientation, which produces posterior-toanterior (PA) current flow in the motor cortex. However, no studies have examined SICI in older adults by reversing the coil to induce anterior-to-posterior (AP) current flow, which is considered more sensitive at detecting SICI. Therefore, we investigated age-related changes in SICI using both PA and AP TMS across different conditioning stimulus intensities and muscle activation states. Methods:In 22 young and 20 older adults, SICI was assessed using PA and AP coil orientations, across a range of conditioning stimulus intensities (70-90% active motor threshold), and whilst participants kept their first dorsal interosseous (FDI) muscle either relaxed or active (2 N force).Results: There were no age-related differences in SICI using conventional PA TMS in resting or active FDI muscle. However, SICI was increased in elderly participants when assessed with reverse coil AP TMS in resting FDI.Conclusions: Coil orientation is a key factor to consider when assessing age-related differences in SICI.Significance: Reverse coil AP TMS can reveal age-related changes in SICI, which were previously not evident with conventional PA TMS. This may have implications for the assessment of SICI in some clinical populations that may show subtle differences in SICI circuitry.

show abstract

Distance-adjusted motor threshold for transcranial magnetic stimulation

Cited by 191 publications

References 37 publications

Theta burst stimulation dissociates attention and action updating in human inferior frontal cortex

Theta burst stimulation dissociates attention and action updating in human inferior frontal cortex

Unilateral and bilateral MRI-targeted repetitive transcranial magnetic stimulation for treatment-resistant depression: a randomized controlled study

Increased intracortical inhibition in elderly adults with anterior–posterior current flow: A TMS study

Contact Info

Product

Resources

About