Research progress and prospect on the mechanisms of non-invasive neuromodulation therapy and acupuncture in treating cognitive impairment after traumatic brain injury.

Cognitive impairment frequently occurs as a secondary effect of traumatic brain injury (TBI) and substantially diminishes patients' quality of life. Non-invasive neuromodulation therapy (NINT) and acupuncture have progressively exhibited therapeutic efficacy for post-traumatic cognitive impairment (PCI) in clinical investigations. However, their clinical efficacy and underlying mechanisms remain unclear. This systematic review aims to clarify the clinical efficacy of acupuncture and the commonly employed NINT and summarizes the underlying mechanisms of their therapeutic effects. Twenty-three clinical studies were analyzed. Transcranial direct current stimulation (tDCS) emerged as the predominant modality for clinical PCI treatment, as evidenced by 15 trials, of which 7 demonstrated favorable benefits, 7 exhibited enhancements in partial indicators, and 1 suggested no efficacy. Despite the discrepancies in research outcomes, tDCS has demonstrated significant therapeutic potential. Few clinical investigations have been conducted on repetitive transcranial magnetic stimulation (rTMS) and acupuncture, demonstrating specific therapeutic outcomes that require validation through high-quality large-sample research. Presently, most clinical investigations have focused on the dorsolateral prefrontal cortex to improve PCI; however, few studies have chosen alternative cognition-related brain regions as stimulation targets. According to fundamental research, previously described therapeutic techniques can enhance cognitive performance by mitigating neuroinflammation, augmenting cerebral blood flow, and decreasing atypical neuronal death. Nonetheless, limitations such as contradictory conclusions on efficacy and difficulties in describing appropriate parameters remain. Future research should use standardized study designs and comprehensive mechanistic investigations to provide substantial evidence for the clinical non-pharmacological treatment of PCI.