Can experimentally induced positive affect attenuate generalization of fear of movement-related pain?

Recent experimental data show that associative learning processes are involved not only in the acquisition but also the spreading of pain-related fear. Clinical studies suggest involvement of positive affect in resilience against chronic pain. Surprisingly, the role of positive affect in associative learning in general and in fear generalization in particular has received scant attention. In a voluntary movement paradigm, in which one arm movement (CS+) was followed by a painful stimulus and another was not (CS-), we tested generalization of fear to five novel but related generalization movements (GSs; within-subjects) after either a positive affect induction or a control exercise (Group = between-subjects) in healthy participants (N = 50). The GSs' similarity with the original CS+ movement and CS- movement varied. Fear learning was assessed via verbal ratings. Results indicated that there was an interaction between the increase in positive affect and the linear generalization gradient. Stronger increases in positive affect were associated with steeper generalization curves due to relatively lower pain-US expectancy and less fear to stimuli more similar to the CS-. There was no Group by Stimulus interaction. Results thus suggest that positive affect may enhance safety learning through promoting generalization from known safe movements to novel yet related movements. Improved safety learning may be a central mechanism underlying the association between positive affect and increased resilience against chronic pain. PERSPECTIVE: We investigated to which extent positive affect influences the generalization (i.e., spreading) of pain-related fear to situations similar to the original, pain-eliciting situation. Results suggest that increasing positive affect in the acute pain stage may limit the spreading of pain-related fear, thereby potentially inhibiting transgression to chronic pain conditions

An experimental investigation into the mediating role of pain-related fear in boosting nocebo hyperalgesia

Health and self-regulatio

The interplay of maternal and offspring obesogenic diets: the impact on offspring metabolism and muscle mitochondria in an outbred mouse model

Consumption of obesogenic (OB) diets increases the prevalence of maternal obesity worldwide, causing major psychological and social burdens in women. Obesity not only impacts the mother’s health and fertility but also elevates the risk of obesity and metabolic disorders in the offspring. Family lifestyle is mostly persistent through generations, possibly contributing to the growing prevalence of obesity. We hypothesized that offspring metabolic health is dependent on both maternal and offspring diet and their interaction. We also hypothesized that the sensitivity of the offspring to the diet may be influenced by the match or mismatch between offspring and maternal diets. To test these hypotheses, outbred Swiss mice were fed a control (C, 10% fat, 7% sugar, and n = 14) or OB diet (60% fat, 20% sugar, and n = 15) for 7 weeks and then mated with the same control males. Mice were maintained on the same corresponding diet during pregnancy and lactation, and the offspring were kept with their mothers until weaning. The study focused only on female offspring, which were equally distributed at weaning and fed C or OB diets for 7 weeks, resulting in four treatment groups: C-born offspring fed C or OB diets (C » C and C » OB) and OB-born offspring fed C or OB diets (OB » C and OB » OB). Adult offspring’s systemic blood profile (lipid and glucose metabolism) and muscle mitochondrial features were assessed. We confirmed that the offspring’s OB diet majorly impacted the offspring’s health by impairing the offspring’s serum glucose and lipid profiles, which are associated with abnormal muscle mitochondrial ultrastructure. Contrarily, maternal OB diet was associated with increased expression of mitochondrial complex markers and mitochondrial morphology in offspring muscle, but no additive effects of (increased sensitivity to) an offspring OB diet were observed in pups born to obese mothers. In contrast, their metabolic profile appeared to be healthier compared to those born to lean mothers and fed an OB diet. These results are in line with the thrifty phenotype hypothesis, suggesting that OB-born offspring are better adapted to an environment with high energy availability later in life. Thus, using a murine outbred model, we could not confirm that maternal obesogenic diets contribute to female familial obesity in the following generations

Chronic primary pain in the COVID-19 pandemic: how uncertainty and stress impact on functioning and suffering.

Health and self-regulatio

Measurement of Th-232(n,5n gamma) cross sections from 29 to 42 MeV

The excitation function of the reaction Th-232(n,5n gamma)Th-228 from 29 to 42 MeV has been measured for the first time at the quasi-monoenergetic neutron beam of the UCL cyclotron CYCLONE employing the Li-7(p,n) source reaction. Taking advantage of the good energy resolution of the planar High Purity Germanium (HPGe) detectors, prompt gamma-ray spectroscopy was used to detect the gamma rays resulting from the decay of excited states of nuclei created by the (n,xn) reactions. The neutron beam was characterized by a combination of time of flight measurements carried out using a liquid scintillation detector and a U-238 fission ionization chamber and fluence measurements carried Out using a proton recoil telescope. The preliminary results are compared with calculations performed using the TALYS-0.72 code.International Conference on Nuclear Data for Science and Technology, Proceedings, Apr 22-27, 2007, Nice, Franc