Interaction between stimulus intensity and perceptual load in the attentional control of pain

Abstract

The interaction between intensity of nociceptive stimuli and cognitive load in a concomitant task is still a challenging and complex topic. Here, we investigated the interaction between top-down factors (i.e., perceptual load), induced by a visual task, and bottom-up factors (i.e., intensity of nociceptive stimuli that implicitly modifies saliency of input). Using a new experimental paradigm, in which perceptual load is varied while laser heat stimuli of different intensities are processed; we show a significant interaction between intensity of nociceptive stimuli and perceptual load on both pain ratings and task performance. High perceptual load specifically reduced intensity ratings of high intensity stimuli. However, under this condition, task performance was impaired, regardless of interindividual differences in motivation and pain catastrophizing. Thus, we showed that pain ratings can be reduced by increasing the load of attentional resources at the perceptual level of a non-pain-related task. Nevertheless, the disruptive effect of highly intensive nociceptive stimuli on the performance of the perceptual task was evident only under high load.

Somatosensory spatial attention modulates amplitudes, latencies, and latency jitter of laser-evoked brain potentials

“…This is in contrast to previous studies indicating that distraction or directing attention away from a noxious stimulus reduces the intensity of pain (McCaul and Malott 1984;Miltner et al 1989;Romero et al 2013;Van Damme et al 2008;Van Ryckeghem et al 2011). However, in most studies, the distraction from a noxious stimulus either coincided with a cognitive task requiring a large amount of attentional resources (Miltner et al 1989) or switching to another sensory modality (Bauer et al 2006;Garcia-Larrea et al 1997;Romero et al 2013;Van Damme et al 2008). In the present study, subjects retrospectively rated the average pain intensity of laser and electrical stimuli, respectively, after each recording block.…”

Somatosensory Abnormalities for Painful and Innocuous Stimuli at the Back and at a Site Distinct from the Region of Pain in Chronic Back Pain Patients

“…In line with Agostinho et al [33] we propose that persistent pain might lead to a centrally mediated impairment of non-painful thermal percept as shown previously in clinical and experimentally-induced pain [30], [34], [35]. Additionally, ongoing pain might reallocate attentional and/or working memory resources [36], [37] or processing of pain-related material [38], [39] possibly resulting in increases of sensory thresholds [40], [41].…”

Dorsal Root Ganglion Stimulation Modulates Cortical Gamma Activity in the Cognitive Dimension of Chronic Pain

“…High-frequency gamma activity has long been associated with cognition and attention [8,9] but has also been shown to encode ongoing pain [10,11]. Moreover, surgically implanted devices such as spinal cord stimulation have shown the potential to modulate cortical gamma (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45) activity [12], supporting the hypothesis of supraspinal mechanisms of action for spinal, and potentially peripheral, neuromodulation.…”

“…Of the patients included in the MEG analysis experiencing pain during the study (n = 11), five reported 50% or greater reduction in reported pain scores with DRGS, while one reported worsening of pain. DRGS-mediated pain relief was associated with a significant reduction in gamma activity (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45) Hz) across all MEG sensors during task performance (t = 2.27, p = 0.036) (See Figure 5A). The observed reduction in gamma band activity during pain relief was predominantly localized to the prefrontal cortex based on source-space analyses, but also revealed reductions in gamma activity in both somatosensory and anterior cingulate cortices after 3D source reconstruction (See Figure 5B).…”