Effect of aging on the cerebral processing of thermal pain in the human brain

Abstract

The perception of pain changes as people age. However, how aging affects the quality of pain and whether specific pain-processing brain regions mediate this effect is unclear. We hypothesized that specific structures in the cerebral nociceptive system mediate the effect of aging on the variation in different pain psychophysical measures. We examined the relationships between painful heat stimulation to the foot and both functional magnetic resonance imaging signals and gray matter volume in 23 healthy subjects (aged 25∼71 years). Increased age was related to decreased subjective ratings of overall pain intensity and the "sharp" quality of pain. Group activation maps of multiple linear regression analyses revealed that age predicted responses in the middle insular cortex (IC) and primary somatosensory cortex (S1) to pain stimuli after controlling for their gray matter volumes. Blood oxygenation level-dependent signals in the contralateral middle IC and S1 were related to ratings of "sharpness," but not any affective descriptors of pain. Importantly, activity in the contralateral middle IC specifically mediated the effect of age on overall pain perception, whereas activity in the contralateral S1 mediated the relationship between age and sharp sensation to pain. The analyses of gray matter volume revealed that key nociceptive cerebral regions did not undergo significant age-related gray matter loss. However, the volume of the cingulate cortex covaried with pain perception after adjusting for corresponding neural activity to pain. These results suggest that age-related functional alterations in pain-processing regions are responsible for changes in pain perception during normal aging.

Low back pain in older adults: risk factors, management options and future directions

“…Both experimental pain and functional neuroimaging studies have found that older people display age-related increase in the heat pain threshold [116] and reduced responses in middle insular and primary somatosensory cortices toward a 44 °C heat stimulus [117]. These age-related neuropsychological changes in pain processing may reduce older peoples’ awareness and reporting of pain that may lead to undiagnosed health problems/injuries.…”

Discrepancy between perceived pain and cortical processing: A voxel-based morphometry and contact heat evoked potential study

“…By accounting for differences in sensitivity to noxious thermal stimuli (Emerson et al, 2014;Erpelding et al, 2012;Grant et al, 2010;Tseng et al, 2013), ability to modulate pain (Piche et al, 2013;Stankewitz et al, 2013;Teutsch et al, 2008), as well as the amplitude of evoked cortical responses to non-noxious afferent stimuli (Fjell et al, 2007;Liem et al, 2012;Muthukumaraswamy et al, 2010), structural magnetic resonance imaging (MRI) has highlighted an important relationship between normal brain anatomy and sensory function. Based on this knowledge, we intended to address the question whether between-subject variability in cortical structure could account for differences in responses to contact heat stimulation in healthy subjects.…”

Neural mechanisms of decision‐making in aging

“…While limited, available evidence suggests that effects of stressful experiences on dopamine-dependent learning are similar in younger and older adults (Lighthall et al, 2013). Neuroimaging studies examining primary reinforcers have shown mixed results, however, with some reporting an age-related increase in neural responses to aversive experiences (taste; Jacobson et al, 2010) and others, an age-related reduction (pain; Tseng et al, 2013). Observed differences in response to primary reinforcers are not well understood, but may be related to variability in age effects on sensory systems (Shaffer & Harrison, 2007).…”