Theta burst stimulation improves overt visual search in spatial neglect independently of attentional load

Objective: To evaluate the effectiveness of theta-burst stimulation for the treatment of stroke-induced unilateral spatial neglect. Data sources: A systematic literature search was conducted from the inception of each database to 30 June 2018 using CINAHL, EMBASE, PubMed, PsycINFO, and Scopus. Review methods: Articles were included if theta-burst stimulation was used to treat neglect following a stroke. The additional a priori inclusion criteria were as follows: (1) ⩾3 adult (⩾18 years) participants, (2) ⩾50% stroke population, and (3) peer-reviewed journal articles published in English. Extracted data included study and treatment characteristics, results, and adverse events. Results: Nine studies met the inclusion criteria, generating a total of 148 participants. Eight studies evaluated a continuous stimulation protocol and one study investigated an intermittent stimulation protocol. Overall, both protocols significantly improved neglect severity when compared against placebo or active controls ( P < 0.05). Adding smooth pursuit training to theta-burst stimulation did not improve neglect relative to when the stimulation was delivered alone ( P > 0.05). There was inconsistent reporting of neglect terminology, outcome measures, and adverse events. The treatment characteristics were heterogeneous among the trials. Conclusion: This systematic review found that theta-burst stimulation seems to improve post-stroke unilateral spatial neglect, but because the evidence is limited to a few small studies with varied and inconsistent protocols and use of terminology, no firm conclusion on effectiveness can be drawn.

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Frontoparietal regions may become hypoactive after intermittent theta burst stimulation over the contralateral homologous cortex in humans

Journal of Neurophysiology ◽

10.1152/jn.00369.2013 ◽

2013 ◽

Vol 110 (12) ◽

pp. 2849-2856 ◽

Cited By ~ 10

Author(s):

Xiaofei He ◽

Yue Lan ◽

Guangqing Xu ◽

Yurong Mao ◽

Zhenghong Chen ◽

...

Keyword(s):

Posterior Parietal Cortex ◽

Spatial Neglect ◽

Attention Network Test ◽

Theta Burst Stimulation ◽

Burst Stimulation ◽

Attention Network ◽

Real Right ◽

The Real ◽

Interhemispheric Competition ◽

Theta Burst

Brain injury to the dorsal frontoparietal networks, including the posterior parietal cortex (PPC) and dorsolateral prefrontal cortex (DLPFC), commonly cause spatial neglect. However, the interaction of these different regions in spatial attention is unclear. The aim of the present study was to investigate whether hyperexcitable neural networks can cause an abnormal interhemispheric inhibition. The Attention Network Test was used to test subjects following intermittent theta burst stimulation (iTBS) to the left or right frontoparietal networks. During the Attention Network Test task, all subjects tolerated each conditioning iTBS without any obvious iTBS-related side effects. Subjects receiving real-right-PPC iTBS showed significant enhancement in both alerting and orienting efficiency compared with those receiving either sham-right-PPC iTBS or real-left-PPC iTBS. Moreover, subjects exposed to the real-right-DLPFC iTBS exhibited significant improvement in both alerting and executive control efficiency, compared with those exposed to either the sham-right-DLPFC or real-left-DLPFC conditioning. Interestingly, compared with subjects exposed to the sham-left-PPC stimuli, subjects exposed to the real-left-PPC iTBS had a significant deficit in the orienting index. The present study indicates that iTBS over the contralateral homologous cortex may induce the hypoactivity of the right PPC through interhemispheric competition in spatial orienting attention.

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