Acoustic neuromodulation with or without micro-voltage tACS reduces post-concussive symptoms

Area of Science:

• Neurology
• Neuroscience
• Military Medicine

Background:

• Persistent post-concussive symptoms (PPCS) significantly impact military service members, with no approved targeted therapies.
• Existing treatments lack focus on underlying physiological mechanisms of PPCS.
• Acoustic neuromodulation and cranial electrical stimulation are emerging therapeutic modalities.

Purpose of the Study:

• To compare the efficacy of acoustic neuromodulation (CR-SOP) versus cranial electrical stimulation (CR-CES) in treating PPCS.
• To assess non-inferiority between different doses of CR-SOP and CR-CES.
• To evaluate secondary outcomes including heart rate variability, PTSD, sleep, headaches, and depression.

Main Methods:

• Eighty participants with PPCS (Neurobehavioral Symptom Inventory [NSI] score ≥23) were randomized.
• Interventions included 10 sessions of CR-SOP (acoustic tones linked to brainwaves) or 5 sessions of CR-CES (CR-SOP + tACS).
• Primary outcome: change in NSI scores; Secondary outcomes: HRV, PCL-5, ISI, HIT-6, PHQ-9.

Main Results:

• Mean NSI scores significantly decreased from 45.6 to 29.5 post-intervention (p < 0.0001), sustained at 3 months.
• No significant difference in NSI scores between CR-SOP and CR-CES groups; non-inferiority was demonstrated.
• Significant improvements observed in PTSD, sleep, headache, and depression measures across both groups.

Conclusions:

• Both CR-SOP and CR-CES significantly improve persistent post-concussive symptoms in military populations.
• The study demonstrates the efficacy of acoustic neuromodulation and adds evidence for CR-CES as a treatment option.
• Improvements were sustained up to three months post-intervention, indicating lasting therapeutic effects.