Quantitative Sensory Testing in adults with Autism Spectrum Disorders

Abstract

Altered sensory perception has been found in patients with autism spectrum disorders (ASD) and might be related to aberrant sensory perception thresholds. We used the well-established, standardized Quantitative sensory testing (QST) protocol of the German Research Network on Neuropathic Pain to investigate 13 somatosensory parameters including thermal and tactile detection and pain thresholds in 13 ASD adults and 13 matched healthy controls with normal IQ values. There were no group differences between somatosensory detection and pain thresholds. Two ASD patients showed paradoxical heat sensations and another two ASD subjects presented dynamic mechanical allodynia; somatosensory features that were absent in controls. These findings suggest that central mechanisms during complex stimulus integration rather than peripheral dysfunctions probably determine somatosensory alterations in ASD.

A Quantitative Sensory Testing Approach to Pain in Autism Spectrum Disorders

“…It must also be noted that the use of a tuning fork for vibrotactile assessment is sensitive enough to identify neuropathy-as intended-however, may not be sensitive enough to measure more subtle changes in threshold. Findings for MDT are in line with Fründt et al (2017) who similarly report a significant loss of function for mechanical detection in ASD participants using the same standardised testing from the QST battery.…”

“…This pattern of findings suggests no systematic change in psychophysically determined pain thresholds for autistic individuals compared to controls. This is not to suggest that pain response in ASD is typical, both Fründt et al (2017) and Duerden et al (2015) report paradoxical heat sensations, a phenomenon where gentle cooling is perceived as hot or burning (Magerl and Klein 2006), in several of their autistic participants. This phenomenon usually does not occur in healthy individuals.…”

“…The focus on a single or a limited number of these submodalities limits previous studies. One study, however, has utilised this full battery, therefore, providing the most comprehensive assessment of somatosensory function in ASD to date (Fründt et al 2017). More extreme somatosensory responses (i.e.…”

“…This study will similarly employ the standardised battery, conducting an independent replication of Fründt et al (2017) and utilise the published normative reference values (Rolke et al 2006) as they provide a determinant of sensory loss and gain that supersedes the standard group differences analysis -meaning clinically significant sensitivities in ASD can be determined. Furthermore, this battery has been extended to include a measure of pain tolerance and central pain processes, utilising the cold pressor test (von Baeyer et al 2005) and Conditioned Pain Modulation (CPM; Yarnitsky et al 2015), respectively.…”

Shank2 expression identifies a subpopulation of glycinergic interneurons involved in nociception and altered in an autism mouse model

“…The common occurrence of self-injury and self-mutilation (including cases of self-extraction of teeth) and unreported wounds (Moore, 2015), together with clinical and experimental studies (Duerden et al, 2015;Klintwall et al, 2011;Tordjman et al, 2009) has been interpreted as evidence of reduced sensitivity to painful stimuli in ASD patients. Conversely, a subset of ASD patients display pain hypersensitivity, in the form of mechanical allodynia (Fründt et al, 2017) reduced threshold for thermal pain (Cascio et al, 2008) or pressure pain (Riquelme et al, 2016;Chen et al, 2017) and chronic pain unrelated to medical conditions (Clarke, 2015;Loades, 2015;Bursch et al, 2004). Pain hypersensitivity may constitute a major and underappreciated source of discomfort for ASD patients, in particular in those unable to properly report it because of reduced communication capabilities (Moore, 2015) and may lead to unnecessary medical procedures (Clarke, 2015).…”