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Background Pain is a subjective experience characterized by sensory (intensity) and emotional (unpleasantness) aspects. Although literature reports behavioural effects on pain due to smell and taste influence, to our knowledge the relationship between tonic pain induced by a capsaicin cream and these chemosensory systems has never been explored before. The aim of this study was to investigate the modulation of olfactory and gustatory substances having different valence on tonic pain perception mediated by a capsaicin cream application. Methods Sixty healthy volunteers were included in two separated experiments (N = 30 smell; N = 30 taste) and underwent different valence smell and taste stimulations, while receiving painful stimuli. Perception of pain intensity (the sensory component) and unpleasantness (the affective component) was measured with a numerical rating scale, both during the two aforementioned experiments. Results Pain unpleasantness rating showed differences only in the smell experiment between the two odourous conditions. In particular, pleasant odour induced lower ratings of pain unpleasantness, while no significant results were found for intensity. Regarding taste, we could not observe significant effects nor for pain unpleasantness or intensity. Conclusions These findings highlight the potential role of pleasant odours in influencing the affective aspects of pain perception induced by this kind of tonic pain. Such evidence might provide new insight for using chemosensory substances as analgesics for modulating the cognitive aspects of neuropathic pain. Significance This work shows the effect of smell on the emotional component of tonic pain, experimentally induced by capsaicin cream application. Previous literature investigated tonic pain in interaction with smell and/or taste stimuli, but mainly with physical methods such as temperature. Our findings add new information in this field, contributing to a deeper insight on the role of olfaction on this particular kind of tonic pain perception. This approach could open to new investigations aimed to consider odours for pain management.

Dementia is a global public health problem and its impact is bound to increase in the next decades, with a rapidly aging world population. Dementia is by no means an obligatory outcome of aging, although its incidence increases exponentially in old age, and its onset may be insidious as a certain amount of non-pathological cognitive decline can be expected with aging. In the absence of unequivocal biomarkers, the accuracy of cognitive profiling plays a fundamental role in the diagnosis of this condition. Here we highlight the utility of brief global cognitive tests in this diagnostic process, from the initial detection stage for which they are designed, to the differential diagnosis of dementia. We also argue that neuropsychological training and expertise are critical in order for the information gathered from these omnibus cognitive tests to be used in an efficient and effective way, and thus, ultimately, for them to have such a utility .

Introduction We tested the hypothesis that functional limb weakness is associated with possible dysfunction of the central processing of proprioceptive information, by evaluating the amount of tonic vibration reflex (TVR) and the perception of the TVR movement. Methods The study sample was 20 patients with functional weakness of the lower and/or the upper limbs and 25 healthy controls; delivery of 92-Hz transcutaneous vibration of the biceps brachii tendon of the unrestrained arm stimulated predominantly the muscle spindle afferent and elicited elbow flexion (tonic vibration reflex, TVR). Blindfolded participants had to match the final position of the vibrated arm with their contralateral tracking arm. The TVR and perception of the TVR movement were measured as angle movements of the vibrated arm and the tracking arm, respectively. Results The magnitude of the TVR of the vibrated arm and movement perception of the TVR of the tracking arm were significantly reduced in the patients compared to the controls. No correlation was found between magnitude of the TVR and perception of the TVR movement, suggesting that the abnormalities were independent of each other. Moreover, the abnormalities did not differ between the patients with/without bilateral upper limb involvement or between the affected and the unaffected side in patients with unilateral impairment, suggesting that the observed deficits are independent of motor impairment. Conclusions Proprioceptive dysfunction may underlie alterations in body movement and in sense of agency in such patients and may play a role in the pathophysiology of functional limb weakness.

Background Pain perception is a multimodal experience composed of sensory, emotional and cognitive dimensions. Accumulating evidence suggests that the chemical senses can influence pain perception, but their relation with phasic pain is still unknown. The aim of this study was to investigate the influence of smell and taste having different valence on phasic pain. Methods Twenty-eight healthy volunteers received sweet, bitter and neutral odours or gustatory substances while receiving painful stimuli consisting of electrical shocks. Tactile threshold, pain threshold and pain tolerance were collected using the psychophysical method of limits at baseline and in association with smell and taste. Perception of pain intensity and unpleasantness was measured with a numerical rating scale. Results Sweet smell induced lower ratings of pain intensity than bitter smell when stimuli were delivered at pain threshold. Sweet smell also induced lower ratings of pain unpleasantness than neutral smell when stimuli were delivered at pain tolerance. Sweet taste induced lower ratings of pain unpleasantness than bitter taste when stimuli were delivered at pain threshold. Conversely, pain threshold and pain tolerance per se were not affected by smell and taste. Conclusions These findings highlight an effect of sweet substances in reducing the subjective perception of pain intensity and unpleasantness associated to phasic pain. Significance By demonstrating the link between smell, taste and phasic pain this study may have a translational impact in clinical conditions characterized by so-called shock-like pain, such as neuropathic pain.

The current COVID-19 pandemic has been officially linked to the deaths of hundreds of thousands of people across the globe in just a few months. It is particularly lethal for the elderly in general, as well as for populations residing in long-term stay facilities. By this time, those working and caring for high-risk populations have been exposed to very intense and sudden levels of physical and psychological strain. The situation has taken a particularly tragic turn in residential nursing and care homes (NCH), which were hit hard by the pandemic. In residential NCH, neither residents nor workers tend to have immediate access to the same expertise, medication and equipment as in hospitals, which exacerbates an already tense situation. Among the mental health conditions related to exposure to potentially traumatic events, post-traumatic stress disorder and anxiety are the most prevalent and scientifically recognized. In this survey-based epidemiological study, we test the prevalence of anxiety and post-traumatic symptomatology in residential nursing and care home workers—a group of individuals that has been largely neglected but who nonetheless plays a very important and sensitive role in our society. We do this by focusing on the North of Italy, the most affected region during the first COVID-19 outbreak in Italy. Using a single-stage cluster design, our study returns an estimate for the prevalence of moderate-to-severe anxiety and/or post-traumatic symptomatology of 43% (s.e. = 3.09; 95% CI [37–49]), with an 18% (s.e. = 1.83; 95% CI [14–22]) prevalence of comorbidity among workers of Northern Italian NCH between 15 June and 25 July 2020 (i.e. 12–52 days after the end of national lockdown). Women and workers who had recently been in contact with COVID-19-positive patients/colleagues are more likely to report moderate-to-severe symptoms, with odds ratios of 2.2 and 1.7, respectively.

Objective Emotional difficulties are common in functional movement disorders (FMD), yet their contribution to the disease remains unclear. We explored the potential role of emotional difficulties as risk and maintaining factors of FMD by looking at the effect of emotions on attention. Method The dot-probe task was used to investigate attentional biases induced by emotional faces in 25 patients with FMD and 25 healthy controls (HC). A pair of faces, one emotional (happy, angry, sad) and the other neutral, was displayed on a monitor to either the left or the right side of a central fixation cross. The face disappeared and a dot was flashed in place of one of the faces. Participants had to indicate the location of the dot. All participants completed the Toronto Alexithymia Scale. Psychological assessment of 23 patients also involved the Short Form Health Survey, the Hamilton Anxiety and the Hamilton Depression Rating Scales. Results A general attentional bias away from emotional faces was noted for the FMD group compared to the HC. A more fine-tuned analysis revealed an attentional bias specifically away from sad faces for the FMD. Conclusion Our findings suggest a specific effect of emotions on attention in FMD that likely involves avoidance of sadness. Since this was not related to alexithymia or mood, we excluded these factors in explaining the results. Attentional bias away from sad faces correlated with general health, suggesting that avoidance of sadness might contribute to the perception of a better general health status in FMD.

Despite the common assumption that atrophy in a certain brain area would compromise the function that it subserves, this is not always the case, especially in complex clinical syndromes such as primary progressive aphasia (PPA). Clinical and demographic information may contribute to PPA phenotypes and explain the manifested impairments better than atrophy. In the present study, we asked how much variance of the object and action naming impairments observed in PPA may be attributed to atrophy in the language network alone vs. additional clinical and demographic factors including language severity and education. Thirty-nine participants with PPA underwent magnetic resonance imaging (MRI) for volumetric analysis and a complete neuropsychological examination, including standardized tests of object and action naming. We used stepwise regression models to compare atrophy (volumetric model) to clinical/demographic variables (clinical-demographic model) for naming objects and actions. The clinical-demographic model was the best-fit model that explained the largest amount of variance in both object and action naming. Brain volume measurements alone explained little variance in both object and action naming. Clinical factors, particularly language severity, and demographic factors, particularly education, need to be considered in conjunction with brain volumes in PPA. The present study emphasizes the complexity of PPA as a syndrome and provides an example of how volumetric, clinical and demographic factors may interact in determining naming performance/deterioration.