RESTING STATE FUNCTIONAL CONNECTIVITY MARKERS FOR THE EFFICACY OF COGNITVE PAIN MODULATION IN AGING

Scientific Conference (2023, March 29)

A growing number of studies suggest that aging is associated with a decrease in efficacy of cognitive pain modulation. Resting state functional connectivity (rsFC) analysis of the brain offers one way of ... [more ▼]

A growing number of studies suggest that aging is associated with a decrease in efficacy of cognitive pain modulation. Resting state functional connectivity (rsFC) analysis of the brain offers one way of investigating the potential neural mechanisms that may underly this age-related decline. In this study, 32 young (26.7 ± 4.3 years) and 32 healthy older (68.3 ± 7.1 years) adults underwent a 6-minute resting state fMRI scan, as well as a pain distraction paradigm. In the latter, participants received painful heat stimuli while performing either an easy or a difficult working memory task. We performed region-of-interest (ROI) to ROI rsFC analysis of the imaging data, focusing on regions implicated in pain processing and descending pain control. We then examined the relationship between rsFC parameters and the magnitude of the distraction effect (the reduction in perceived pain intensity during the difficult vs the easy task). Older adults showed reduced connectivity compared to young adults between several descending pain modulatory regions, including the ACC and PAG, the right secondary somatosensory cortex (SII) and right dorsolateral prefrontal cortex and between the ACC and left amygdala. Importantly, rsFC in older adults correlated positively with the distraction effect, between several regions including the right SI and right amygdala, the left SI and right insula and between the ACC and left amygdala. Our findings thus demonstrate, for the first time, that reduced cognitive pain modulation in older age is directly associated with decreased rsFC within key nodes of the descending pain control network. [less ▲]

Cognitive distraction from pain: An fMRI study on the role of age and executive functions

Scientific Conference (2021, June)

Completing a cognitive task has been shown to be a powerful strategy to reduce concurrent pain. This reduction in pain is assumed to result from a competition between the painful stimulus and the ... [more ▼]

Completing a cognitive task has been shown to be a powerful strategy to reduce concurrent pain. This reduction in pain is assumed to result from a competition between the painful stimulus and the distractive task for attentional and executive resources mediated by the prefrontal cortex (PFC), a region that is particularly affected by age-related grey matter atrophy. In the present study, we investigated the role of age-related changes in gray matter volume and executive functions in modulating the efficacy of distraction from pain. In a first session, young and older adults completed a battery of neuropsychological tests. In a second session, we acquired functional brain images while participants completed a working memory task with two levels of cognitive load (low vs. high load) and concurrently received individually adjusted heat stimuli (innocuous vs. painful) to their lower arm. While we found no age-related differences in the distraction effect size on the behavioural level, young adults showed a larger neural distraction effect in several regions involved in pain processing, including the insula, caudate and midcingulate cortex. Interestingly, older adults with better executive functions, particularly, better inhibitory control abilities, showed a larger neural distraction effect in the insula, thalamus and primary somatosensory cortex, and more activation in frontal clusters during the high load task. Taken together, these findings suggest that age alters the neural mechanisms underlying cognitive distraction from pain, and that the magnitude of these changes may be dependent on the preservation of executive functions. [less ▲]

Distraction from Pain: An fMRI Study on the Role of Age-related Changes in Executive Functions

Scientific Conference (2021, June)

Even though aging is associated with increased and prolonged episodes of pain, little is known about potential age-related changes in the "top-down" modulation of pain, such as cognitive distraction from ... [more ▼]

Even though aging is associated with increased and prolonged episodes of pain, little is known about potential age-related changes in the "top-down" modulation of pain, such as cognitive distraction from pain. The hypoalgesic effect of distraction results from a competition for attentional and executive resources mediated by the prefrontal cortex (PFC). Given that age-related grey matter atrophy is particularly prominent in the PFC, older adults may benefit less from distraction to reduce pain than young adults. The aim of this study was to investigate the influence of aging on task-related hypoalgesia and its neural mechanisms, with a focus on the role of executive functions in distraction from pain. 64 participants (32 young adults: 26.69 ± 4.14 years; 32 older adults: 68.28 ± 7.00 years) first completed a battery of neuropsychological tests. In a second session, we administered a pain distraction paradigm while functional brain images were acquired. In this paradigm, participants completed a low (0-back) and a high (2-back) load condition of a working memory task while receiving either innocuous or painful heat stimuli to their lower arm. To control for age-related differences in sensitivity to pain and perceived task difficulty, stimulus intensity and task speed were individually calibrated. Both age groups showed significantly reduced activity in a network of regions involved in pain processing when performing the high compared to the low load distraction task; however, young adults showed a larger neural distraction effect in several of these regions, including the insula, caudate and midcingulate cortex. Moreover, in older adults, better executive functions – in particular inhibitory control abilities – were associated with a larger neural distraction effect in the insula, thalamus and primary somatosensory cortex, and with more activation in several prefrontal cortex regions during the high load task. These findings clearly demonstrate that the top-down control of pain is altered by age and could explain the higher vulnerability of older adults to developing chronic pain. Moreover, our findings suggest that the assessment of executive functions may be a useful tool for predicting the efficacy of cognitive pain modulation strategies in older adults. [less ▲]

Distraction from pain: The role of selective attention and pain catastrophizing

in European Journal of Pain (2020), 24(10), 1880-1891

Age-Related Changes in Pain Perception Are Associated With Altered Functional Connectivity During Resting State

in Frontiers in Aging Neuroscience (2020), 12(116),

The role of executive functions in task-related analgesia

Poster (2019, March)

Introduction: Recent research suggests that weaker executive functions may be linked to a higher risk of pain chronicity. However, little is known about how executive functions affect the modulation of ... [more ▼]

Introduction: Recent research suggests that weaker executive functions may be linked to a higher risk of pain chronicity. However, little is known about how executive functions affect the modulation of acute pain. The present study aimed to investigate the impact of inhibitory control on the success of cognitive distraction from pain. Methods: Participants completed a battery of cognitive tasks (Go/NoGo, Color Stroop, Eriksen Flanker), assessing their cognitive inhibition and selective attention abilities. Additionally, self-report measures of pain catastrophizing and fear of pain were administered. In a pain distraction paradigm, participants completed either a cognitively demanding working memory task (2-back task) or a visually matched easy control task (target response task) while receiving warm or painful thermal stimuli to their left forearm. Nociceptive stimulus intensity was individually calibrated for each participant. Moreover, to maintain a similar level of task difficulty across participants, task speed was continuously adapted based on the participant's performance in the previous trials. Following each trial, participants rated the perceived intensity and unpleasantness of the thermal stimuli on visual analogue scales. Results: As expected, preliminary results indicate that the 2-back task, but not the target response task, successfully distracted participants from thermal pain, manifesting in significantly lower intensity and unpleasantness ratings. Importantly, the magnitude of the distraction effect was negatively associated with the Flanker effect. Discussion: In line with previous research, engaging in a cognitively demanding task led to significantly lower pain intensity and unpleasantness ratings when compared to an easy control task. Moreover, results indicate that better interference control abilities may predict greater task-related analgesia. Taken together, the results of the present study suggest that it is crucial to assess executive functions to develop a better understanding of the mechanisms behind cognitive distraction from pain. [less ▲]

Reduced modulatory effects of distraction on pain due to aging

Scientific Conference (2018, July)

Maternal separation stress leads to resilience against neuropathic pain in adulthood

in Neurobiology of Stress (2018), 8

The combination of postnatal maternal separation and social stress in young adulthood does not lead to enhanced inflammatory pain sensitivity and depressionrelated behavior in rats

in PLoS ONE (2018), 13(8), 0202599

Assessing suffering in experimental pain models: psychological and psychophysiological correlates

in Zeitschrift für Psychologie (2017), 225(1), 45-53

Although suffering is a central issue in pain, there is only little research on this topic. The aim of this study was to assess suffering in an experimental context using various stimulation methods and ... [more ▼]

Although suffering is a central issue in pain, there is only little research on this topic. The aim of this study was to assess suffering in an experimental context using various stimulation methods and durations, and to examine which psychological or psychophysiological measures covary with pain-related suffering. Twenty-one healthy volunteers participated in two experiments in which we used tonic thermal and phasic electric stimuli with short and long stimulus durations. The participants rated pain intensity, unpleasantness, and pain-related suffering on separate visual analog scales (VAS) and completed the Pictorial Representation of Illness and Self Measure (PRISM), originally developed to assess suffering in chronic illness. We measured heart rate, skin conductance responses (SCRs), and the electromyogram (EMG) of the musculus corrugator supercilii. For both heat and electric pain, we obtained high ratings on the suffering scale confirming that suffering can be evoked in experimental pain conditions. Whereas pain intensity and unpleasantness were highly correlated, both scales were less highly related to suffering, indicating that suffering is distinct from pain intensity and unpleasantness. Higher suffering ratings were associated with more pronounced fear of pain and increased private self-consciousness. Pain-related suffering was also related to high resting heart rate, increased SCR, and decreased EMG during painful stimulation. These results offer an approach to the assessment of suffering in an experimental setting using thermal and electric pain stimulation and shed light on its psychological and psychophysiological correlates. [less ▲]