scholarly journals Onset hyperalgesia and offset analgesia: Transient increases or decreases of noxious thermal stimulus intensity robustly modulate subsequent perceived pain intensity

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0231124
Author(s):  
Benedict J. Alter ◽  
Mya Sandi Aung ◽  
Irina A. Strigo ◽  
Howard L. Fields
Keyword(s):  
Pain Intensity ◽  
Stimulus Intensity ◽  
Noxious Stimulus ◽  
Thermal Stimulus ◽  
Experienced Pain ◽  
Perceived Pain ◽  
Subjective Pain ◽  
Higher Temperature ◽  
Absolute Magnitudes ◽  
Lower Temperature

Reported pain intensity depends not only on stimulus intensity but also on previously experienced pain. A painfully hot temperature applied to the skin evokes a lower subjective pain intensity if immediately preceded by a higher temperature, a phenomenon called offset analgesia. Previous work indicated that prior pain experience can also increase subsequent perceived pain intensity. Therefore, we examined whether a given noxious stimulus is experienced as more intense when it is preceded by an increase from a lower temperature. Using healthy volunteer subjects, we observed a disproportionate increase in pain intensity at a given stimulus intensity when this intensity is preceded by a rise from a lower intensity. This disproportionate increase is similar in magnitude to that of offset analgesia. We call this effect onset hyperalgesia. Control stimuli, in which a noxious temperature is held constant, demonstrate that onset hyperalgesia is distinct from receptor or central sensitization. The absolute magnitudes of offset analgesia and onset hyperalgesia correlate with each other but not with the noxious stimulus temperature. Finally, the magnitude of both offset analgesia and onset hyperalgesia depends on preceding temperature changes. Overall, this study demonstrates that the perceptual effect of a noxious thermal stimulus is influenced in a bidirectional manner depending upon both the intensity and direction of change of the immediately preceding thermal stimulus.

scholarly journals The onset and offset of noxious stimuli robustly modulate perceived pain intensity

2020 ◽  
Author(s):  
Benedict J. Alter ◽  
Mya Sandi Aung ◽  
Irina A. Strigo ◽  
Howard L. Fields
Keyword(s):  
Pain Intensity ◽  
Stimulus Intensity ◽  
Stimulus Change ◽  
Noxious Stimulus ◽  
Noxious Heat ◽  
Temperature Changes ◽  
Hot Temperature ◽  
Experienced Pain ◽  
Subjective Pain ◽  
Higher Temperature

AbstractReported pain intensity depends not only on stimulus intensity but also on previously experienced pain. A painfully hot temperature applied to the skin evokes a lower subjective pain intensity if immediately preceded by a higher temperature, a phenomenon called offset analgesia. This is typically evoked using a three-step noxious heat stimulus. In other clinical and laboratory settings, prior pain experience may increase pain intensity as well. Therefore, we hypothesized that even small increases in stimulus intensity within the noxious range would be accompanied by enhanced reported pain intensity. To test this possibility, we inverted the intensity order of the three-step stimulus, so that the same hot temperature is immediately preceded by an increase from a transiently lowered temperature. Using healthy volunteer subjects, we observed a disproportionate increase in pain intensity during the novel, inverted, three-step stimulus. This disproportionate increase is similar in magnitude to that of offset analgesia. Control stimuli demonstrate that these changes in pain intensity are distinct from habituation. The magnitudes of offset analgesia and the disproportionate increase in pain intensity correlate with each other but not with the absolute noxious stimulus temperature. These observations suggest that the disproportionate increase in pain intensity represents an “onset hyperalgesia.” Finally, the magnitude of both offset analgesia and onset hyperalgesia depends on preceding temperature changes. Overall, this study finds that perceptual enhancement of noxious stimulus change occurs bidirectionally and that this depends on the intensity and direction of change of the immediately preceding stimulus.

Transient Analgesia Evoked by Noxious Stimulus Offset

2002 ◽  
Vol 87 (4) ◽  
pp. 2205-2208 ◽  
Author(s):  
Joshua D. Grill ◽  
Robert C. Coghill
Keyword(s):  
Chronic Pain ◽  
Pain Intensity ◽  
Relative Proportion ◽  
Noxious Stimulus ◽  
Temporal Contrast ◽  
Nociceptive Processing ◽  
Perceived Pain ◽  
Pain Ratings ◽  
Stimulus Offset ◽  
Escape Behaviors

Pain has long been thought to wax and wane in relative proportion to fluctuations in the intensity of noxious stimuli. Dynamic aspects of nociceptive processing, however, remain poorly characterized. Here we show that small decreases (±1–3°C) in noxious stimulus temperatures (47–50°C) evoked changes in perceived pain intensity that were as much as 271% greater than those of equal magnitude increases. These decreases in perceived pain intensity were sufficiently large to be indistinguishable from those evoked by 15°C decreases to clearly innocuous levels. Furthermore, decreases in pain ratings following noxious stimulus offset were significantly greater than those occurring during adaptation to constant temperature stimuli. Together, these findings indicate that an analgesic mechanism is activated during noxious stimulus offset. This analgesic phenomenon may serve as a temporal contrast enhancement mechanism to amplify awareness of stimulus offset and to reinforce escape behaviors. Disruption of this mechanism may contribute importantly to chronic pain.

scholarly journals Pain-Related and Negative Semantic Priming Enhances Perceived Pain Intensity

2014 ◽  
Vol 19 (2) ◽  
pp. 69-74 ◽  
Author(s):  
Maria Richter ◽  
Christoph Schroeter ◽  
Theresa Puensch ◽  
Thomas Straube ◽  
Holger Hecht ◽  
...  
Keyword(s):  
Pain Intensity ◽  
Semantic Priming ◽  
Moderate Intensity ◽  
Dependent Manner ◽  
Negative Valence ◽  
Experimental Parameters ◽  
Perceived Pain ◽  
Pain Ratings ◽  
Subjective Pain ◽  
Noxious Stimuli

BACKGROUND: Negative affective and pain-related cues, such as pictures or words, have been shown to act as primes and enhance the perceived intensity of subsequent painful events. For pain-related semantic primes, it remains unclear whether this effect depends on negative valence itself or, specifically, on the pain-relatedness of the words.OBJECTIVES: To investigate the effect of pain-related, negative affective (pain-unrelated) and neutral semantic primes on the perception of subsequent noxious target stimuli.METHODS: Pain ratings in response to noxious electrical stimulation of light and moderate intensity were examined in 39 healthy subjects after subjects were exposed to semantic primes of different meaning and valence (pain-related, negative, positive and neutral adjectives) presented with different interstimulus intervals (0 ms, 500 ms and 1500 ms).RESULTS: Increased pain ratings of noxious stimuli were observed following pain-related and negative compared with neutral primes.DISCUSSION: The results support the motivational priming theory for semantic stimuli, indicating that affectively negative semantic primes increase subjective pain intensity. However, a specific pain-related priming effect was not reliably demonstrated. Additionally, it is shown that experimental parameters (ie, stimulus intensity and interstimulus interval) modify the extent of negative and pain-related semantic priming.CONCLUSIONS: Verbal priming plays a role for the perception of noxious stimuli in a time-dependent manner.

scholarly journals Does EEG activity during painful stimulation mirror more closely the noxious stimulus intensity or the subjective pain sensation?

2018 ◽  
Vol 35 (3-4) ◽  
pp. 192-198
Author(s):  
Stefanie F. Bunk ◽  
Stefan Lautenbacher ◽  
Jascha Rüsseler ◽  
Karin Müller ◽  
Jana Schultz ◽  
...  
Keyword(s):  
Stimulus Intensity ◽  
Noxious Stimulus ◽  
Pain Sensation ◽  
Eeg Activity ◽  
Painful Stimulation ◽  
Subjective Pain

scholarly journals Brain oscillations differentially encode noxious stimulus intensity and pain intensity

NeuroImage ◽  
2017 ◽  
Vol 148 ◽  
pp. 141-147 ◽  
Author(s):  
Moritz M. Nickel ◽  
Elisabeth S. May ◽  
Laura Tiemann ◽  
Paul Schmidt ◽  
Martina Postorino ◽  
...  
Keyword(s):  
Pain Intensity ◽  
Stimulus Intensity ◽  
Noxious Stimulus ◽  
Brain Oscillations

scholarly journals Neural markers of nociceptive input and pain intensity coding: a signal detection approach

2019 ◽  
Author(s):  
Brianna Beck ◽  
Stephanie Cook ◽  
Giandomenico Iannetti ◽  
Patrick Haggard
Keyword(s):  
Electrical Stimulation ◽  
Signal Detection ◽  
Pain Intensity ◽  
Stimulus Intensity ◽  
Pain Perception ◽  
Electrical Stimulus ◽  
Afferent Input ◽  
Individual Variability ◽  
Healthy Human ◽  
Subjective Pain

The N2 and P2 vertex waves are the largest electroencephalographic (EEG) responses evoked by transient nociceptive stimuli. N2 and P2 amplitudes often correlate with both stimulus energy and pain intensity. However, studies using paradigms that dissociated afferent input from stimulus salience suggested the N2 and P2 waves primarily reflect supramodal salience, rather than being selective for nociception or pain. Here we investigated how well EEG responses to nociceptive laser stimuli discriminate stimulus intensities and subjective pain in healthy human volunteers. Specifically, we applied signal detection theory (SDT) to calculate how well single-trial amplitudes of stimulus-related EEG responses (contralateral N1 wave, vertex N2 and P2 waves, and gamma-band oscillations) discriminate between two laser energies (neuro-d’obj), and between participants’ reports of “high” or “low” pain intensity (neuro-d’subj). As a control, we applied the same procedure to similar brain potentials evoked by non-painful electrical stimulation. Participants’ perceptual sensitivity to stimulus intensity (d’) was similar between modalities, indicating that laser and electrical stimulus discriminations were similarly difficult. Laser-evoked N1, N2 and P2 waves were sensitive to stimulus intensity, whereas the same waves evoked by electrical stimulation showed minimal sensitivity. Inter-individual differences in laser-evoked N1, N2 and P2 neuro-d’obj also predicted inter-individual variability in nociceptive sensitivity (d’). Together, these findings show that the laser-evoked potential—elicited by stimuli at long, variable intervals—reflects nociceptive intensity discrimination. Further, the laser-evoked N2 wave captured trial-by-trial variability in pain perception that was unrelated to stimulus intensity. This indicates that the N2 carries particular information about subjective pain intensity.

Circle therapy for headache management: case studies

2020 ◽  
Vol 24 (1) ◽  
pp. 101-104
Author(s):  
Muhammad Rafiq
Keyword(s):  
Pain Intensity ◽  
Case Studies ◽  
Rating Scale ◽  
Psychological Pain ◽  
Current Case ◽  
Paired Samples ◽  
Subjective Pain ◽  
Headache Management ◽  
Test Use ◽  
Pain Rating Scale

Recent findings have indicated that hypnotic interventions produce significant decrease in pain intensity. This current case studies are focused to highlight significant impact on pain management including headache. All the patients underwent a complete observation and clinical interview and only patients with psychological pain were included in the study group. For the management of headache, a novel hypnotic intervention - Circle Therapy (CT), was applied on a group of ten patients indicating their pain intensity in the range of 8-10 on subjective pain rating scale. According to rating scale, headache above 8 was considered as severe, 5-8 moderate and < 5 as mild.  CT is a brief hypnotic technique limited to about 10 min. Post hypnosis ratings were also measured. The pre and post hypnosis data were recorded and analyzed by paired samples t test. Use of CT showed significant results between pre and post rating e.g. 9 ± 0.25 vs. 1 ± 0.21 (p < 0.001). This brief CT intervention provided an immediate relief from headache, however, this is limited to few case studies focusing on just headache. So, we recommend large sample studies to document the effects of CT in different types of pain. Citation: Rafiq M. Circle therapy for headache management: case studies. Anaesth pain intensive care 2020;24(1):__ DOI: https://doi.org/10.35975/apic.v24i1. Received – 28 December 2019; Reviewed – 10 January 2020; Accepted - 10 January 2020;

scholarly journals Sprouting of Sorghum (Sorghum bicolor [L.] Moench): Effect of Drying Treatment on Protein and Starch Features

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 407 ◽  
Author(s):  
Mia Marchini ◽  
Alessandra Marti ◽  
Claudia Folli ◽  
Barbara Prandi ◽  
Tommaso Ganino ◽  
...  
Keyword(s):  
Food Production ◽  
Cost Effective ◽  
High Exposure ◽  
Effective Technology ◽  
Drying Treatment ◽  
Higher Temperature ◽  
Lower Temperature ◽  
The One ◽  
Drying Conditions ◽  
Sorghum Bicolor L

The nutritional and physicochemical properties of sorghum proteins and starch make the use of this cereal for food production challenging. Sprouting is a cost-effective technology to improve the nutritional and functional profile of grains. Two drying treatments were used after sorghum sprouting to investigate whether the drying phase could improve the protein and starch functionalities. Results showed that the drying treatment at lower temperature/longer time (40 °C for 12 h) extended the enzymatic activity that started during sprouting compared to the one performed at higher temperature/shorter time (50 °C for 6 h). An increased protein hydrolysis and water- and oil-holding capacity were found in the flour obtained by the former treatment. Higher protein matrix hydrolysis caused high exposure of starch to enzymes, thus increasing its digestibility, while worsening the technological functionality. Overall, modulating drying conditions could represent a further way, in addition to sprouting, to improve sorghum flour’s nutritional profile.

Sign in / Sign up

Export Citation Format

Share Document