A study from Fernando Pessoa University in Porto has identified the “neuroemotional face of saudade” (longing), revealing its scientific coding and facial expression patterns by discovering a biomarker for this emotion. The research, conducted by the Laboratory of Facial Expression of Emotion at the university's Faculty of Medicine and led by Freitas-Magalhães, confirms that saudade is a neurobiologically based emotion with specific brain circuits and a codifiable facial expression. The findings, which represent nearly two decades of work, allow this complex emotion to be measured and studied with precision, with potential applications in medicine, clinical psychology, affective neuroscience, and artificial intelligence.