Tactile Thresholds are Preserved yet Cortical Sensory Function is Impaired in Chronic Non-Specific Low Back Pain Patients

Introduction: A substantial amount of evidence points to an alteration in brain structure and function patients with chronic non-specific low back pain (CNSLBP) [1-6]. One interpretation of these findings is that the observed brain changes may represent a disruption of the brain’s representations of the body part and the resultant body perception disturbance may underpin this clinical problem. The current study aimed to investigate sensory dysfunction in CNSLBP. Specifically we aimed to distinguish cortically mediated sensory dysfunction from peripheral dysfunction by comparing simple tactile thresholds with more complex cortically mediated sensory tests Methods: We investigated tactile thresholds (TTH), two point discrimination (TPD) and graphaesthesia over the lumbar spine of 19 CLBP patients and 19 age and sex matched healthy controls as a way of investigating whether CLBP patients present with a perceptual disturbance of their lumbar spine. Differences in performance of the sensory tests was explored using the Mann Whitney U Test and one-way between groups multivariate analysis of variance. Results: We found no difference in tactile threshold between the two groups (P=.0.751). There was a statistically significant difference between controls and LBP for TPD: F(1,36)=10.15, p=.003 and letter error rate: F(1, 36)=6.54 p=0.015. The data indicate that LBP patients had a larger lumbar TPD distance and a greater letter recognition error rate. Discussion: Both TPD and graphaesthesia are dependant on the integrity of the primary sensory cortex [7]. These data support existing findings of perceptual abnormality in chronic back pain [8] and the preservation of tactile thresholds is suggestive of cortical rather than peripheral sensory dysfunction. Amelioration of these abnormalities may present a target for therapeutic intervention

Effects of the glial modulator palmitoylethanolamide on chronic pain intensity and brain function.

Background: Chronic neuropathic pain (NP) is a complex disease that results from damage or presumed damage to the somatosensory nervous system. Current treatment regimens are often ineffective. The major impediment in developing effective treatments is our limited understanding of the underlying mechanisms. Preclinical evidence suggests that glial changes are crucial for the development of NP and a recent study reported oscillatory activity differences within the ascending pain pathway at frequencies similar to that of cyclic gliotransmission in NP. Furthermore, there is evidence that glial modifying medications may be effective in treating NP. The aim of this Phase I open-label clinical trial is to determine whether glial modifying medication palmitoylethanolamide (PEA) will reduce NP and whether this is associated with reductions in oscillatory activity within the pain pathway. Methods: We investigated whether 6 weeks of PEA treatment would reduce pain and infra-slow oscillatory activity within the ascending trigeminal pathway in 22 individuals (17 females) with chronic orofacial NP. Results: PEA reduced pain in 16 (73%) of the 22 subjects, 11 subjects showed pain reduction of over 20%. Whilst both the responders and non-responders showed reductions in infra-slow oscillatory activity where orofacial nociceptor afferents terminate in the brainstem, only responders displayed reductions in the thalamus. Furthermore, functional connections between the brainstem and thalamus were altered only in responders. Conclusion: PEA is effective at relieving NP. This reduction is coupled to a reduction in resting oscillations along the ascending pain pathway that are likely driven by rhythmic astrocytic gliotransmission

Tactile thresholds are preserved yet complex sensory function is impaired over the lumbar spine of chronic non-specific low back pain patients: A preliminary investigation

Evidence indicates that chronic non-specific low back pain (CNSLBP) is associated with alteration in the brain’s cortical representation of the back, resulting in body perception disturbance and contributing to the condition [1,2]. This study investigated perception via ‘cortical’ sensory tests, in this case two-point discrimination and graphaesthesia—whose results partly depend on the integrity of cortical representation [2]. The hypothesis was dysfunction in these higher-order tasks, with simple tactile thresholds remaining unchanged. Furthermore a relationship between cortical sensation and severity of the condition was predicted

Functional changes in the primary somatosensory cortex in complex regional pain syndrome (CRPS): A systematic review

The brain plays a key role in CRPS. A widely-studied brain region in pain research is the primary somatosensory cortex (S1), a somatotopic map of our body’s surface which functionally reorganises in pain [1]. Changes in the S1 representation of the CRPS-affected body part have contributed to new CRPS treatments, e.g. graded motor imagery. This systematic review and meta-analysis aimed to determine whether CRPS is associated with: a) a change in the size of the S1 representation of the affected body part; b) altered S1 activity, in terms of activation levels and latency of responses

Tactile thresholds are preserved yet complex sensory function is impaired over the lumbar spine of chronic non-specific low back pain patients. A preliminary investigation

Objectives: To investigate impairments in sensory function in chronic non-specific low back pain patients and the relationship between any impairment and the clinical features of the condition. Design: A cross-sectional case-control study. Setting: Laboratory based study. Participants: Nineteen chronic non-specific low back pain patients and nineteen healthy controls. Main Outcome measures: Tactile threshold, two point discrimination distance and accuracy at a task involving recognizing letters drawn over the skin of the lower back (graphaesthesia) were assessed over the lumbar spine in both groups. Pain duration, pain intensity, physical function, anxiety and depression were assessed by questionnaire in the back pain group Results: We found no difference in tactile threshold between the two groups (median difference 0.00 95% CI -0.04 – 0.04). There was a significant difference between controls and back pain patients for two point discrimination (mean difference 17.85 95% CI 5.93 – 29.77) and graphaesthesia accuracy (mean difference 6.13 95% CI 1.27-10.99). Low back pain patients had a larger lumbar two point discrimination distance threshold and a greater letter recognition error rate. In the patient group, we found no relationship between clinical profile and sensory function and no relationship between the sensory tests. Conclusions: These data support existing findings of perceptual abnormalities in chronic non-specific low back pain patients and are suggestive of cortical rather than peripheral sensory dysfunction. Amelioration of these abnormalities may present a target for therapeutic intervention

Use of Machine Learning to Investigate the Quantitative Checklist for Autism in Toddlers (Q-CHAT) towards Early Autism Screening.

In the past two decades, several screening instruments were developed to detect toddlers who may be autistic both in clinical and unselected samples. Among others, the Quantitative CHecklist for Autism in Toddlers (Q-CHAT) is a quantitative and normally distributed measure of autistic traits that demonstrates good psychometric properties in different settings and cultures. Recently, machine learning (ML) has been applied to behavioral science to improve the classification performance of autism screening and diagnostic tools, but mainly in children, adolescents, and adults. In this study, we used ML to investigate the accuracy and reliability of the Q-CHAT in discriminating young autistic children from those without. Five different ML algorithms (random forest (RF), naïve Bayes (NB), support vector machine (SVM), logistic regression (LR), and K-nearest neighbors (KNN)) were applied to investigate the complete set of Q-CHAT items. Our results showed that ML achieved an overall accuracy of 90%, and the SVM was the most effective, being able to classify autism with 95% accuracy. Furthermore, using the SVM-recursive feature elimination (RFE) approach, we selected a subset of 14 items ensuring 91% accuracy, while 83% accuracy was obtained from the 3 best discriminating items in common to ours and the previously reported Q-CHAT-10. This evidence confirms the high performance and cross-cultural validity of the Q-CHAT, and supports the application of ML to create shorter and faster versions of the instrument, maintaining high classification accuracy, to be used as a quick, easy, and high-performance tool in primary-care settings

Prevalence and correlates of food insecurity among children in high-income European countries. A systematic review.

Background. In Europe, there is not routinely collected data on children’s food insecurity. Indirect data show that food insecurity is on the rise in Europe, which may have a great impact on children’s health. Methods. Considering that, we systematically reviewed any evidence coming from European countries in the last 10 years that reported the prevalence and correlates of food insecurity among children, intending to serve as a starting point for policymakers and guidelines. Results. We report worrying prevalence rates of food insecurity among children from 9 studies. There is a lack of evidence regarding this issue in many EU countries, especially Eastern Europe. Hence, the need for increased attention towards food insecurity among children in European countries. Conclusions. Achieving food security means designing targeted policies and interventions, both at a national and EU level. Policymakers and governments should make the appropriate efforts to deliver food security as a public good

Valorization of traditional Italian walnut (Juglans regia L.) production: genetic, nutritional and sensory characterization of locally grown varieties in the Trentino region

15openYesJuglans regia (L.) is cultivated worldwide for its nutrient-rich nuts. In Italy, despite the growing demand, walnut cultivation has gone through a strong decline in recent decades, which led to Italy being among the top five net importing countries. To promote the development of local high-quality Italian walnut production, we devised a multidisciplinary project to highlight the distinctive traits of three varieties grown in the mountainous region Trentino (northeast of Italy): the heirloom ‘Bleggiana’, a second local accession called local Franquette and the French cultivar ‘Lara’, recently introduced in the local production to increase yield. The genetic characterization confirmed the uniqueness of ‘Bleggiana’ and revealed local Franquette as a newly described autochthonous variety, thus named ‘Blegette’. The metabolic profiles highlighted a valuable nutritional composition of the local varieties, richer in polyphenols and with a lower ω-6/ω-3 ratio than the commercial ‘Lara’. ‘Blegette’ obtained the highest preference scores from consumers for both the visual aspect and tasting; however, the volatile organic compound profiles did not discriminate among the characterized cultivars. The described local varieties represent an interesting reservoir of walnut genetic diversity and quality properties, which deserve future investigation on agronomically useful traits (e.g., local adaptation and water usage) for a high-quality and sustainable production.Di Pierro, Erica A.; Franceschi, Pietro; Endrizzi, Isabella; Farneti, Brian; Poles, Lara; Masuero, Domenico; Khomenko, Iuliia; Trenti, Francesco; Marrano, Annarita; Vrhovsek, Urska; Gasperi, Flavia; Biasioli, Franco; Guella, Graziano; Bianco, Luca; Troggio, MichelaDi Pierro, E.A.; Franceschi, P.; Endrizzi, I.; Farneti, B.; Poles, L.; Masuero, D.; Khomenko, I.; Trenti, F.; Marrano, A.; Vrhovsek, U.; Gasperi, F.; Biasioli, F.; Guella, G.; Bianco, L.; Troggio, M