Differentiating trait pain from state pain: a window into brain mechanisms underlying how we experience and cope with pain

Figures

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  Figure 1.. Set point concept. A schematic representation of a “set point concept” to describe biological and psychological attributes of an individual. In a healthy condition, an individual trait (ie, a basal state) is represented by a set point. This set point is not necessarily a “point” but a small range of values. Deviations from this set point range can occur into higher or lower “states” as conditions change transiently. However, after an injury or in disease/pathological conditions, the set point may change and represent a “new normal” trait, from which further deviations to different states are possible.

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  Figure 2.. Fluctuations in chronic pain. (A) Daily fluctuations in ratings of chronic pain in 3 patients with chronic pain are shown in this example and illustrate cases in which patients exhibit different degrees of day-to-day variability in their pain experience, yet exhibit a similar overall mean level of pain as assessed over 1 month. Daily pain measures represent state pain, and the mean level of pain assessed over a month represents trait pain (modified with permission36). (B) Circadian patterns of pain in patients with diabetic neuropathy (left) and postherpetic neuralgia (right) illustrate how pain varies over time (with permission32). NRS, numerical rating scale; dplns, dorsal posterior insula.

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  Figure 3.. Multivariate brain functional connectivity models for state and trait pain. Displayed for each model are the top-10 most important brain features (largest multivariate weights) in the model for state and trait pain derived from resting state functional connectivity data and pain intensity ratings in 71 patients with chronic neuropathic pain. dFC, dynamic functional connectivity; sFC, static functional connectivity (modified with permission6); dplns, dorsal posterior insula; PO, parietal operculum.