A systematic review of the neurobiological effects of theta-burst stimulation (TBS) as measured using functional magnetic resonance imaging (fMRI)

Abstract

Theta burst stimulation (TBS) is associated with a range of clinical, cognitive, and behavioural outcomes, but specific neurobiological effects remain somewhat unclear. This systematic literature review investigated resting-state and task-based functional magnetic resonance imaging (fMRI) outcomes post TBS in healthy human adults. Forty-two studies that applied either continuous- or intermittent- (c/i) TBS, and adopted a pretest-posttest and/or sham-controlled design, were included. For resting-state outcomes following stimulation applied to motor, temporal, parietal, occipital, or cerebellar regions, functional connectivity generally decreased in response to cTBS and increased in response to iTBS, though there were some exceptions to this pattern of response. This is mostly consistent with the assumed long-term depression (LTD)/long-term potentiation (LTP)-like plasticity effects of cTBS and iTBS, respectively. Task-related outcomes following TBS were more variable. TBS applied to the frontal cortex, irrespective of task or state, also produced more variable responses, with no consistent patterns emerging. Individual participant and methodological factors are likely to contribute to the variability in responses to TBS. Future studies assessing the effects of TBS via fMRI must account for factors known to affect the response to TBS, both at the level of individual participants and of research methodology.

Psychomotor Slowing in Psychosis and Inhibitory Repetitive Transcranial Magnetic Stimulation

“…While the neural changes associated with rTMS are out of the scope of this report, we need to explore the probability that repeated iTBS with a pause of 10 minutes may exert inhibitory effects in some participants. [51][52][53][54][55] Changes in the severity of catatonia or negative symptoms were noted between treatment arms. BFCRS total scores and BFCRS subscores indicating decreased motor activity were ameliorated with 1-Hz rTMS, whereas BNSS anhedonia scores improved with iTBS stimulation (eFigure 1 in Supplement 2).…”

Transcranial Magnetic Stimulation for the Treatment of Chemo Brain

“…Our exciting findings have demonstrated that TMS restored the disrupted connectivity of DLPFC. A systematic review [62] has revealed that TBS possesses the capability to reverse functional connectivity, thereby exerting an impact on the functioning of diverse brain regions. These findings align with the hypothesized long-term depression (LTD) and long-term potentiation (LTP)-like plasticity effects.…”

Diffusion MRI–guided theta burst stimulation enhances memory and functional connectivity along the inferior longitudinal fasciculus in mild cognitive impairment

“…Previous TBS studies stimulating the primary motor cortex have found that iTBS usually enhances cortical excitability, while cTBS suppresses cortical excitability, presumably reflecting long-term potentiation and long-term depression effects, respectively ( 61 , 62 ). TBS studies targeting the left parietal lobe observed increased functional connectivity in cognitive networks following iTBS and decreased functional connectivity in response to cTBS ( 63 ). Our study is in agreement with these previous findings and suggests that iTBS might cause memory enhancement compared to cTBS.…”