Professor Shigeto Yamawaki, ACNP Fellow Emeritus, former President of the International College of Neuropsychopharmacology (CINP), Founding President of the Asian College of Neuropsychopharmacology (AsCNP), and former President of the Japanese Society of Neuropsychopharmacology (JSNP), passed away on June 8, 2026.

Professor Yamawaki was one of the most influential leaders in international neuropsychopharmacology and biological psychiatry. Throughout a distinguished academic career spanning more than four decades, he combined scientific excellence, visionary leadership, and an unwavering commitment to improving the lives of patients suffering from mental illness.

A lifelong member of Hiroshima University, he established one of Japan’s leading centers for biological psychiatry and translational neuroscience. His scientific work evolved continuously throughout his career. Early studies demonstrated that chronic lithium treatment increases brain-derived neurotrophic factor (BDNF) expression in the brain, helping to establish neurotrophic mechanisms underlying mood stabilization [1]. He later showed that environmental stress can induce epigenetic alterations in BDNF regulation, linking stress, neuroplasticity, and vulnerability to depression [2].

Professor Yamawaki was also among the pioneers who introduced modern neuroimaging approaches into Japanese psychiatry. In collaboration with Kenji Doya and colleagues, he contributed to a landmark study demonstrating that immediate and future rewards are processed by distinct cortico-basal ganglia circuits [3]. His scientific interests subsequently expanded to synaptic plasticity, biomarker-guided psychiatry, and computational neuroscience. A particularly influential contribution was the demonstration that the BDNF pro-peptide plays an active role in hippocampal synaptic plasticity and is altered by the common Val66Met polymorphism [4]. Even in the final years of his career, he remained intellectually adventurous, co-authoring innovative theoretical work with Karl Friston on active interoceptive inference and the neural basis of subjective experience [5].

Professor Yamawaki became an ACNP member in 2004 and was later recognized as a Fellow Emeritus. He was a familiar and highly respected participant at ACNP Annual Meetings and attended several International Leadership Meetings. Colleagues valued his thoughtful contributions, broad international perspective, and commitment to strengthening scientific collaboration across continents.

His influence extended far beyond his own research. As Founding President of AsCNP and later President of CINP (2014–2016), he worked tirelessly to strengthen neuropsychopharmacology throughout Asia and to foster productive collaborations among scientists in Asia, Europe, and North America. He was also a strong advocate for translational neuroscience, psychiatric drug development, and public–private partnerships aimed at accelerating innovation in mental health research.

Those who knew Professor Yamawaki remember not only his scientific accomplishments but also his warmth, humility, generosity, and remarkable energy. Despite significant health challenges later in life, he remained deeply engaged in research, education, mentorship, and scientific leadership. Colleagues often described him as a “small giant,” reflecting the extraordinary influence he had on the field and on those around him.

In 2024, CINP recognized his lifetime achievements with the CINP Pioneer Award. Yet perhaps his greatest legacy lies in the countless investigators, clinicians, trainees, and patients whose lives were touched by his work and example. Through his scholarship, leadership, and humanity, he helped shape modern neuropsychopharmacology in Japan, Asia, and throughout the world.

Professor Yamawaki will be remembered with deep respect, gratitude, and affection throughout the global neuropsychopharmacology community. We extend our heartfelt condolences to his family, friends, colleagues, and former trainees.