Burst-like conditioning electrical stimulation is more efficacious than continuous stimulation for inducing secondary hyperalgesia in humans

Abstract

The aim of the present study was to compare the efficacy of burst-like conditioning electrical stimulation vs. continuous stimulation of cutaneous nociceptors for inducing increased pinprick sensitivity in the surrounding unstimulated skin (a phenomenon referred to as secondary hyperalgesia). In a first experiment ( n = 30), we compared the increase in mechanical pinprick sensitivity induced by 50-Hz burst-like stimulation ( n = 15) vs. 5-Hz continuous stimulation ( n = 15) while maintaining constant the total number of stimuli and the total duration of stimulation. We found a significantly greater increase in mechanical pinprick sensitivity in the surrounding unstimulated skin after 50-Hz burst-like stimulation compared with 5-Hz continuous stimulation ( P = 0.013, Cohen’s d = 0.970). Importantly, to control for the different frequency of stimulation, we compared in a second experiment ( n = 40) 5-Hz continuous stimulation ( n = 20) vs. 5-Hz burst-like stimulation ( n = 20), this time while keeping the total number of stimuli as well as the frequency of stimulation identical. Again, we found a significantly greater increase in pinprick sensitivity after 5-Hz burst-like stimulation compared with 5-Hz continuous stimulation ( P = 0.009, Cohen’s d = 0.868). To conclude, our data indicate that burst-like conditioning electrical stimulation is more efficacious than continuous stimulation for inducing secondary hyperalgesia. NEW & NOTEWORTHY Burst-like electrical conditioning stimulation of cutaneous nociceptors is more efficacious than continuous stimulation for inducing heterosynaptic facilitation of mechanical nociceptive input in humans.

No evidence for an effect of selective spatial attention on the development of secondary hyperalgesia: A replication study

“…One electrode was placed on each forearm at 8 cm distance from the middle of the cubital fossa (see Figure 1A for more details). Electrical stimulation was generated by two constant current electrical stimulators (DS7A; Digitimer Ltd., Welwyn Garden City, UK) and consisted of 500 square-wave pulses spread in 12 trains (single pulse-width 2 ms) of 100 Hz lasting about 0.42 s each, with an inter-train interval of 9 s (i.e., burst-like stimulation; see Gousset et al, 2020 ). Total HFS duration was about 2 min.…”

Priming of central and peripheral mechanisms with heat and cutaneous capsaicin facilitates secondary hyperalgesia to high-frequency electrical stimulation

“…Neither was rekindling of the heat/capsaicin method was performed (Dirks and Petersen 2003) and therefore unclear whether maintaining increased peripheral sensitization would have affected the results. To further limit discomfort, a relatively low intensity for HFS was also applied compared to studies from Van den Broeke and colleagues (van den Broeke et al 2016;Van den Broeke et al 2019;Gousset et al 2020), which could have affected the amount of secondary hyperalgesia.…”

Within‐ and between‐session reliability of secondary hyperalgesia induced by electrical high‐frequency stimulation

“…In addition, capsaicin or heat typically induces after-sensations, which is not the case for electrical stimulation. Furthermore, parameters such as the pattern and frequency of electrical stimulation can be easily controlled, which has recently led to the finding that burst-like 42 Hz stimulation seem the optimal parameters for inducing SH (Van Den Broeke et al, 2019;Gousset et al, 2019).…”