Related Experiment Video
Updated: Mar 28, 2026
Investigations on Alterations of Hippocampal Circuit Function Following Mild Traumatic Brain Injury
Published on: November 19, 2012
Mild traumatic brain injury alters function in the dorsolateral prefrontal cortex: a TMS-EEG study
Emily Moore1, Emily Webb1, Ryoki Sasaki1
1Discipline of Physiology, School of Biomedicine, The University of Adelaide, Adelaide, Australia.
Objective:
The neurophysiological effects of mild traumatic brain injury (mTBI) in cognitive brain areas remains limited. We addressed this limitation by using electroencephalography to index responses to transcranial magnetic stimulation (TMS-EEG) over the dorsolateral prefrontal cortex (DLPFC).
Methods:
TMS-EEG was used to index cortical inhibition (via paired-pulse TMS) and long-term depression (LTD)-like plasticity (via continuous theta burst stimulation [cTBS]) within DLPFC in 18 mTBI patients and 22 controls. Functional effects of injury were assessed via the N-back and Trail Making Test. Responses were quantified in both temporal (i.e., TMS-evoked potentials; TEPs) and spectral (i.e., TMS-related oscillations; TROs) domains.
Results:
For TEPs, measures of inhibition and plasticity both tended to be reduced by mTBI. In contrast, TRO data suggested an increased response of patients to both paired-pulse stimulation and cTBS that was specific to high-frequency bands. In addition, while TMT performance was reduced in the mTBI group, this was unrelated to neurophysiological effects of injury.
Conclusions:
While DLPFC function is altered following mTBI, the nature of this effect depends on how the data is examined (considering evoked vs. induced activity).
Significance:
These findings highlight novel effects of mTBI on DLPFC neurophysiology, possibly reflecting dysregulated cortical inhibitory function and neuroplasticity.
