Painoprosessin

Painoprosessin, or pain processing, refers to the physiological and psychological processes involved in the detection, transmission, modulation, and perception of pain. It spans from initial transduction of noxious stimuli by peripheral nociceptors to the subjective experience of pain and its behavioral responses. Pain processing comprises sensory-discriminative, affective-motivational, and cognitive-evaluative dimensions.

Nociception begins with transduction at nociceptors, then transmission via A-delta and C fibers to the dorsal horn of the spinal cord, ascension through pathways such as the spinothalamic tract to the thalamus, and onward to cortical and subcortical regions including the somatosensory cortex, insula, anterior cingulate cortex, and prefrontal cortex. The sensory-discriminative aspect localizes intensity and location; the affective and cognitive aspects modulate the emotional burden and interpretation.

Pain processing is modulated by endogenous systems that can dampen or amplify signals. Descending pathways from the brainstem, including the periaqueductal gray and nucleus raphe magnus, modulate spinal nociceptive transmission. Central sensitization, glial activation, and synaptic plasticity can sustain or amplify pain, contributing to chronic pain. External factors such as mood, attention, context, and prior experiences influence perception.

Clinical relevance: understanding pain processing informs assessment and treatment, including pharmacological approaches (analgesics, NSAIDs, opioids when appropriate), and non-pharmacological strategies (physical therapy, cognitive-behavioral therapy, mindfulness, neuromodulation).