A randomised controlled trial comparing the effects of transcranial pulse stimulation and EEG neurofeedback on sustained attention and depressive symptoms in young adults.

Background: Non-pharmacological interventions for sustained-attention difficulties in young adults remain limited. Transcranial pulse stimulation (TPS), a focused ultrasound-based neuromodulation technique, has shown preliminary promise in improving neuropsychiatric symptoms, but its effects on sustained attention in young adults are unclear. We therefore compared TPS with electroencephalography (EEG)-based theta-beta ratio (TBR) neurofeedback (NF) and a wait-list control (WLC) in young adults with subclinical sustained-attention difficulties. Methods: This single-centre, three-arm, parallel-group randomised controlled trial enrolled right-handed adults aged 20-34 years with subclinical sustained-attention difficulties. Participants were assigned to TPS, NF, or WLC. Both active interventions comprised 12 sessions over 4 weeks. Primary outcomes were performance indices from the Conners Continuous Performance Test, Third Edition (CPT-3), including detectability (d'), omission errors, commission errors, perseverations, hit reaction time (HRT), HRT standard deviation, reaction-time variability, HRT block change, and HRT interstimulus-interval change. Secondary outcomes included self-report measures of attentional control, psychological distress, anxiety, depression, self-esteem, social connectedness, and additional cognitive tasks. Outcomes were analysed using linear mixed-effects models with false discovery rate correction. Results: Fifty-seven participants were analysed (TPS = 22, NF = 12, WLC = 23; mean age = 24.2 years; 60% female). At post-treatment, TPS showed greater improvement than NF on 8 of 9 CPT-3 outcomes (false discovery rate-adjusted q = 0.001-0.033; Cohen's d = -0.93 to -1.61) and greater improvement than WLC on 5 of 9 CPT-3 outcomes (q = 0.001-0.031; d = -0.75 to -1.39). NF did not outperform WLC on any CPT-3 outcome. Among subjective-report outcomes, TPS showed a greater reduction in depressive symptoms than NF (Hospital Anxiety and Depression Scale-Depression, q = 0.028; d = -0.91), whereas no other between-group differences survived correction. No between-group differences in CPT-3 outcomes survived correction at 1- to 3-month follow-up. No serious adverse events occurred. Exploratory EEG analyses suggested successful modulation of the trained TBR target in the NF group, but this did not translate into measurable cognitive benefit. Conclusions: TPS was associated with greater short-term improvement in sustained attention than NF or WLC in young adults with subclinical attention difficulties. However, durability remains uncertain because between-group effects were not maintained at follow-up. Larger, blinded, sham-controlled trials are needed to determine the specificity, clinical significance, and longer-term durability of TPS effects.