The Role of Pain Expectations in the Development of Secondary Pinprick Hypersensitivity: Behavioral-Neurophysiological Evidence and the Role of Pain-Related Fear.

Secondary mechanical hypersensitivity, a common symptom of neuropathic pain, reflects increased responsiveness of nociceptive pathways and can be induced temporarily in healthy volunteers using high-frequency electrical stimulation of the skin. Expectations modulate acute pain perception and fear of pain has been shown to attenuate and amplify the placebo and nocebo effects, respectively. However, the role of expectations and fear in the development of mechanical secondary hypersensitivity remains unclear.

No Evidence That Working Memory Modulates the Plasticity of the Nociceptive System, as Measured by Secondary Mechanical Hypersensitivity.

The effect of cognition on the plasticity of the nociceptive system remains controversial. In this study, we examined whether working memory can buffer against the development of secondary hypersensitivity. Thirty-five healthy women participated in 3 experimental conditions.

The effect of high versus low cognitive load on the development of nociceptive hypersensitivity: The roles of sympathetic arousal, sex and pain-related fear.

Background: According to limited-capacity theories of attention, less attentional resources remain available when engaging in a high- versus a low-demanding cognitive task. This may reduce the perceived intensity and the evoked cortical responses of concomitant nociceptive stimuli. Whether and how the competition for limited attentional resources between a cognitive task and pain impacts the development of long-lasting hypersensitivity is unclear.

The Effect of Observing High or Low Pain on the Development of Central Sensitization.

It is unknown whether watching other people in high pain increases mechanical hypersensitivity induced by pain. We applied high-frequency electrical stimulation (HFS) on the skin of healthy volunteers to induce pinprick mechanical hypersensitivity. Before HFS participants were randomly allocated to 2 groups: in the low pain group, which was the control condition, they watched a model expressing and reporting lower pain scores, in the high pain group the model expressed and reported higher scores.