None listed
Conditions
Brief summary
Transcranial magnetic stimulation (TMS) is a non-invasive brain stimulation technique that uses a momentary electromagnetic pulse to activate localised areas of brain tissue. A patterned form of TMS called Theta Burst Stimulation (TBS) appears to induce temporary plastic-like change in the brain. The technique has proven useful in treating disorders (e.g depression). However, individual response to TBS varies in neuroscience research and clinical treatment. Indeed approximately 40% of depression sufferers are not helped by TBS. Recent evidence suggests this variation may be due to TBS activating different groups of brain cells in different people, the latter of which can be measured using common TMS outcome metrics. Given mixed evidence, the proposed research will comprehensively examine the degree to which common TMS outcome metrics can predict TBS response. Investigating and controlling sources of variability in TBS could lead to greatly improved neuroscientific knowledge and clinical outcomes.
Interventions
Eligible participants will be invited to attend two two-hour assessment sessions separated by at least one week. Participants will give written informed consent at the commencement of the first session. Prior to the commencement of TMS in both sessions, participants will be given a safety questionnaire to assess their eligibility for TMS.
Those who meet project eligibility will then proceed by being administered a common battery of single and paired-pulse TMS procedures, administered via a Mag
Eligible participants will be invited to attend two two-hour assessment sessions separated by at least one week. Participants will give written informed consent at the commencement of the first session. Prior to the commencement of TMS in both sessions, participants will be given a safety questionnaire to assess their eligibility for TMS. Those who meet project eligibility will then proceed by being administered a common battery of single and paired-pulse TMS procedures, administered via a MagStim BiStim2. Then the participants will receive either continuous or intermittent Theta Burst Stimulation (cTBS / iTBS) to the hand node of the primary motor cortex administered via a MagStim Rapid- these sessions will be counter balanced. cTBS will be administered at 50 Hz repeating at 5 Hz giving a total of 600 pulses over 40 seconds. iTBS will be consist of bursts of three pulses delivered at 50 Hz delivered in a two second train repeated every 10 seconds for 20 repetitions giving a total of 600 pulses. TMS will be administered by a trained TMS researcher with 3 years experience. Five minutes after TBS the participants will receive a group of single TMS pulses applied with two different coil orientations, to assess their response to TBS. These groups will be repeated at five-minute intervals until 30 minutes after TBS. This marks the end of the stimulation and at this point participants will be given a post stimulation safety screening questionnaire to monitor the unlikely occurrence of any negative effects experienced. The second session will be the same as the first session save for the different TBS protocol used (i.e. if session 1 involves cTBS then session 2 will involve iTBS and vice versa).
Sponsors
Deakin University
Study design
Allocation
Non-randomised trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
To be included in the study participants must be healthy adults aged 18 to 45, be proficient in English in order to be able to provide informed consent, and meet the screening criteria outlined below.
Exclusion criteria
Anyone who demonstrates a contra-indication for TMS. This includes (but is not limited to): • History of seizure • Previous clinical EEG where presence of seizure activity has not been excluded • Professional driver or machine operator • Previous brain surgery or brain injury • Ferromagnetic metal in the head outside of the mouth • Implanted medical device • Serious or unstable illness or medical condition • Current or suspected pregnancy or current lactation • Any illicit drug use within past 7 days • Any alcohol use in past 12 hours, or more than 3 standard drinks in past 24 hours Recent insomnia or another form of sleep deprivation Further, children will not be asked to participate in this project since their inclusion is not required (or necessary) for the study aims to be achieved. People with intellectual or mental impairment and those highly dependent on medical care will be excluded since some health conditions are contraindicators of the TMS procedure that we propose to adopt in this project. These are appropriately (as per Deakin University procedures) screened for as part of the proposed screening protocol described later. People whose primary language is not English will be disadvantaged on some of the assessment tasks which were developed, and where appropriately normed, for English speaking individuals. Accordingly, these assessments are unlikely to provide a true representation of a non-English speaking individuals' abilities and hence they will be excluded from participation. In the case of the exclusion of pregnant women, pregnancy is a contraindication of the TMS procedures that we propose to adopt in this project.
Outcome results
None listed