Evaluating the effect of transcranial magnetic stimulation in patients with
disorder of consciousness with functional near-infrared spectroscopy
Mengsha Lv
1
, Bin Lv
1
, Jianghong He
2
& Tongning Wu
1
1
China Academy of Information and Communication Technology, Beijing, China, 100191
2
PLA Army General Hospital, Beijing, China, 100000
BioEM2017, Hangzhou, China, Jun 05 - 09, 2017
Presented by: Bin Lv
Our ultimate objective is to apply fNIRS to explore the modulation effect of TMS on
patients with disorder of consciousness(DOC). In this abstract, we presented the
experimental design and preliminary results in healthy people. First, we designed
passive and active movement task. Second, we performed single-pulse TMS
stimulation and TMS-like sound stimulation. We collected and compared the fNIRS
data. Our current results indicated that passive movement task can modulate the
brain activation as well as active movement task. Therefore we could apply passive
movement task for DOC patients in subsequent experiment. Meanwhile, the
significant activation was detected during the real TMS stimulation, while not in the
TMS-like sound stimulation.
Introduction
Transcranial magnetic stimulation (TMS) is a painless, non-invasive brain stimulation
technique in neuroscience and clinical studies [1].The magnetic signal can be
attenuated through the skull to stimulate the intracranial nerve and make the cerebral
cortex excited. There are two types of transcranial magnetic stimulator: single-pulse
transcranial magnetic stimulator and repetitive pulse transcranial magnetic stimulator
(rTMS). Recently, TMS has started to be used for improving the treatment in brain
function recovery of patients with disorder of consciousness (DOC), including
vegetative state (VS) or minimally consciousness state (MCS) patients [2, 3]. One case
reported that 3 of 10 patients in MCS had significant clinical improvement by using a
protocol of TMS over dorsolateral prefrontal cortex,
Functional near-infrared spectroscopy (fNIRS) is a noninvasive optical imaging
technology to detect the brain activities which is based on the absorption and
scattering properties of near-infrared lighted in different brain tissues [4]. The
detected signals include the local concentration changes of oxygenated hemoglobin
([oxy-Hb]), deoxygenated hemoglobin ([deoxy-Hb]) and their total hemoglobin
([total-Hb]). Compared to other neuroimaging techniques (e.g. fMRI, EEG), fNIRS is
more portable with its small size, and has the characteristics of strong
anti-interference, convenient wearing of light cap and convenient data collection. Due
to its advantages, researchers have attempted to apply fNIRS for the conscious state
assessment in DOC patients [5, 6]. Kempny et al. found the fNIRS response
differences between healthy subjects and DOC patients during both motor
movement and motor movement imagery [5]. Molteni et al. designed three tasks,
including somatosensory stimulation, passive movement stimulation and active
movement stimulation. They obtained the significant results from 2 DOC patients
that the NIRS channels showing activation completely correspond to regions of
residual cortex underneath [6]. Those results indicated the huge potentialities of