Systemic Failures in Human Neuroscience Trials and How to Fix Them

Clinical trials in neuroscience have resulted in significant improvements, but they have also revealed persistent flaws in safety assessment, participant consent, ethics, and post-trial device/technology governance. This review combines high-impact incidents, regulatory analyses, and empirical studies to identify recurring failure modes: incomplete preclinical translation resulting in catastrophic adverse events, inadequately informed consent (particularly for cognitively vulnerable participants), ethically fraught placebo/sham surgical designs, insufficient long-term follow-up and device maintenance, data governance and cybersecurity gaps, and underreporting of harms. We examine representative case studies (such as the TGN1412 cytokine storm, the BIA 10-2474 FAAH inhibitor neurotoxicity, arguments about sham surgery in deep brain stimulation, and device post-trial care failures) to demonstrate systemic causes and consequences. For each shortcoming, we propose specific solutions, including updated preclinical-to-human dose strategies, improved consent processes (layered consent and ongoing consent assessment), independent safety oversight for high-risk first-in-human studies, device stewardship policies for implanted neurotechnologies, and increased transparency and adverse-event reporting. To our knowledge, no thorough analysis has rigorously examined the linked ethical, technological, regulatory, and methodological flaws found in all types of human neuroscience clinical trials globally. The existing literature is compartmentalized, focusing on individual case studies, ethical issues, or device-specific failures. This is the first integrated framework that combines translational failures, consent vulnerabilities, sham surgery controversies, neurodevice stewardship gaps, data governance deficiencies, and post-trial obligations into a unified failure-mode taxonomy, backed up by cross-regional analysis and high-impact case data. The analysis closes with a recommended checklist and research agenda for making neuroscience studies safer, more ethical, and socially responsible.