GRIEF AND THE BRAIN: NEUROBIOLOGICAL EVIDENCE AND PSYCHIATRIC REPERCUSSIONS IN ADULTS

Abstract

INTRODUCTION: Grief is a natural response to the loss of a significant person and involves emotional, cognitive, behavioral, and physiological changes. Although it is generally adaptive, in some individuals distress may persist and impair functioning, resulting in manifestations consistent with Prolonged Grief Disorder. Evidence points to the involvement of neurobiological mechanisms related to emotional processing, memory, stress response, motivation, and reward. OBJECTIVE: To analyze the available evidence on neurobiological changes associated with grief in adults and their psychiatric, cognitive, and functional repercussions. MATERIALS AND METHODS: An integrative literature review was conducted using the PubMed/MEDLINE, Scopus, Web of Science, SciELO, and LILACS databases. Controlled descriptors and free-text terms related to grief and neurobiology were combined using the Boolean operators AND and OR. Studies published between 2003 and 2025 in Portuguese, English, or Spanish were included if they involved bereaved adults and addressed neurobiological, psychiatric, cognitive, or functional aspects. Study selection was performed through title and abstract screening, followed by full-text assessment and qualitative synthesis of the eligible studies. RESULTS: A total of 311 records were identified, of which 97 were duplicates. After screening 214 records, 168 were excluded. Of the 46 articles sought for full-text retrieval, four could not be retrieved, and 42 were assessed for eligibility. After 30 studies were excluded, 12 comprised the final sample. The findings showed changes involving the amygdala, cingulate cortices, prefrontal regions, nucleus accumbens, and reward-related circuits, as well as alterations in the hypothalamic-pituitary-adrenal axis, cortisol levels, immunoinflammatory markers, and the oxytocinergic system. Associations with persistent yearning, intrusive thoughts, difficulties in emotional regulation, and cognitive and functional changes were also reported. CONCLUSION: Grief involves complex and interrelated neurobiological mechanisms, particularly those related to emotional processing, cognitive regulation, stress response, and reward. In prolonged manifestations, these changes may be associated with psychiatric, cognitive, and functional repercussions. However, the heterogeneity of the available studies still prevents the definition of specific biomarkers for the diagnosis of Prolonged Grief Disorder, reinforcing the need for an integrated interpretation of biological, psychological, and clinical findings.