Negative emotions as modulators of inflammation and chronic pain: from PNEI and PNSI to fibromyalgia

The relationships between emotional processes, the nervous system and the immuneresponse are an area of growing interest for psychoneuroendocrinoimmunological (PNEI)research. Numerous studies suggest that persistent stress, difficulties in emotion regulation andsome psychopathological conditions are associated with alterations in specific inflammatorymarkers. Such associations, however, are not uniform and do not necessarily imply a directcausal relationship.This article proposes a narrative review of the main interactions between emotional stress,neuroendocrine regulation, immunity and chronic pain, framed within psychoneurosomaticintegrative (PNSI) approach, a clinical-operational orientation that integrates PNEI withattention to the subjective, relational and contextual dimension of the illness experience. Therole of the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, cytokinesand the gut-brain axis is examined, distinguishing documented biological mechanisms fromhypotheses still under investigation. Particular attention is devoted to fibromyalgia, a complexcondition characterized by widespread pain, fatigue, sleep disturbances and frequent cognitiveand emotional difficulties, in which alterations in pain processing and possible neuroimmunemodifications have been described.The role of emotion regulation, alexithymia and pain catastrophizing is also discussed,together with the clinical implications of psychological interventions, meditative practices andclinical hypnosis. The aim is to propose an integrated mind-body model that acknowledgesthe relevance of psychological processes without reducing chronic pain to an exclusivelypsychological condition or attributing to emotions biological effects that have not beenadequately demonstrated.