Somatosensory Information Processing in the Aging Population

Abstract

While it is well known that skin physiology – and consequently sensitivity to peripheral stimuli – degrades with age, what is less appreciated is that centrally mediated mechanisms allow for maintenance of the same degree of functionality in processing these peripheral inputs and interacting with the external environment. In order to demonstrate this concept, we obtained observations of processing speed, sensitivity (thresholds), discriminative capacity, and adaptation metrics on subjects ranging in age from 18 to 70. The results indicate that although reaction speed and sensory thresholds change with age, discriminative capacity, and adaptation metrics do not. The significance of these findings is that similar metrics of adaptation have been demonstrated to change significantly when the central nervous system (CNS) is compromised. Such compromise has been demonstrated in subject populations with autism, chronic pain, acute NMDA receptor block, concussion, and with tactile–thermal interactions. If the metric of adaptation parallels cortical plasticity, the results of the current study suggest that the CNS in the aging population is still capable of plastic changes, and this cortical plasticity could be the mechanism that compensates for the degradations that are known to naturally occur with age. Thus, these quantitative measures – since they can be obtained efficiently and objectively, and appear to deviate from normative values significantly with systemic cortical alterations – could be useful indicators of cerebral cortical health.

Measuring psychometric characteristics of the elderly sensory responsivity questionnaire– A tool for screening sensory processing difficulties in elderly adults

“…This supports the claim of Zheng et al [34] mentioned above, regarding plasticity of the central nervous system in the elderly. In addition, the fact that only independent participants with general good health participated in the present study may also contribute to this result.…”

“…This plasticity may compensate for the sensory processing changes and should be taken into consideration in intervention programs for the elderly, which also focus on function maintenance [34] .…”

Centrally-mediated sensory information processing is impacted with increased alcohol consumption in college-aged individuals

“…The measure that we currently use to describe the impact that conditioning stimuli have on some aspect of sensory discriminative capacity -but most often amplitude discriminative capacity -is the adaptation metric, a value which has been demonstrated to be relatively constant across a large age spectrum of healthy controls (Zhang et al, 2011b). However, the adaptation metric for a number of neurological conditions has been demonstrated to be reduced or below normative values.…”

“…Previously, we reported that the ability of an individual to perceive the difference between two simultaneouslydelivered vibratory stimuli to the skin can be impacted significantly by relatively brief (0.2 to 2 s) periods of preexposure to conditioning stimuli (Folger et al, 2008;Francisco et al, 2011;Tannan et al, 2006Tannan et al, , 2007Tannan et al, , 2008Tommerdahl et al, 2007aTommerdahl et al, , 2007bTommerdahl et al, , 2010aZhang et al, 2008Zhang et al, , 2009Zhang et al, , 2011aZhang et al, , 2011b. The measure that we currently use to describe the impact that conditioning stimuli have on some aspect of sensory discriminative capacity -but most often amplitude discriminative capacity -is the adaptation metric, a value which has been demonstrated to be relatively constant across a large age spectrum of healthy controls (Zhang et al, 2011b).…”

Widespread Pressure Pain Hypersensitivity in Elderly Subjects with Unilateral Thumb Carpometacarpal Osteoarthritis

“…Nevertheless, the individuals included in our study were recruited from an old population and a similar study should also be conducted in younger subjects to evaluate if these findings are similar for all subjects with thumb CMC OA. In fact, discrepancies on pressure pain sensitivity can be related to age-related changes in anatomical, physiological, and biomechanical structures of peripheral pathways involved in pain processing [20,49].…”