Multiple brain networks mediating stimulus-pain relationships in humans

Abstract

1The brain transforms nociceptive input into a complex pain experience comprised of 2 sensory, affective, motivational, and cognitive components. However, it is still unclear how pain 3 arises from nociceptive input, and which brain networks coordinate to generate pain 4 experiences. We introduce a new high-dimensional mediation analysis technique to estimate 5 distributed, network-level patterns mediating the relationship between stimulus intensity and 6 pain. In a large-scale analysis of functional magnetic resonance imaging data (N=284), we 7 identify both traditional mediators in somatosensory brain regions and additional mediators 8 located in prefrontal, midbrain, striatal, and default-mode regions unrelated to nociception in 9 standard analyses. The whole brain mediators are specific for pain vs. aversive sounds and are 10 organized in five functional networks. Brain mediators explain 32% more within-subject variance 11 of single-trial pain ratings than previous brain-based models. Our results provide a new, broader 12 view of the networks underlying pain experience, as well as distinct targets for interventions. 13

Low somatosensory cortex excitability in the acute stage of low back pain causes chronic pain

“…During chronic pain, the decreased activation incidence of thalamus, S1, S2, IC and ACC is contrasted by increased activation incidence of the pre-frontal cortex (PFC) compared with pain processing in healthy, pain-free individuals (90-92). It is widely agreed that chronic pain states have stronger affective, motivational, and cognitive components and this underpins the preferential activation of the PFC (90, 93). Whilst activity within the PFC was not directly measured in our study, psychological functions associated with these regions were.…”

Functional MRI Can Be Highly Reliable, but It Depends on What You Measure: A Commentary on Elliott et al. (2020)

“…In contrast, test-retest reliabilities of individual regions (e.g., amygdala) were much lower ( r s = .11–.27). In a second example, we assessed the same-day test-retest reliability of the neurologic pain signature—a neuromarker for evoked pain—in eight fMRI studies ( N = 228; data from Geuter et al, 2020; Jepma et al, 2018). Reliability was good to excellent in all studies (Fig.…”

The Brain Activation-based Sexual Image Classifier (BASIC): A sensitive and specific fMRI activity pattern for sexual image perception

“…Genital arousal levels could in addition be assessed during the fMRI scan (Arnow et al, 2009) and brain response patterns predicting genital arousal levels and self-reported sexual arousal could be compared. This type of study design would allow for a mediation analysis, which could give more insight in the brain organization by examining the distributed, network-level patterns that mediate the stimulus intensity effects on sexual arousal (Geuter et al, 2020).…”