Neuroreport
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Excitatory amino acids (EAAs) play a critical role in the development of peripheral tactile and thermal hypersensitivity after the induction of paw inflammation in rats. We used a spinal microdialysis model to examine the effect of complete Freund's adjuvant (CFA)-induced inflammation on the spinal release of EAAs and assessed the antinociceptive effect of pulsed radiofrequency (PRF). CFA was injected into the plantar surface of the left hind paw to induce inflammation. ⋯ The behavior tests showed that PRF administered to the anterior ramus, just distal to the intervertebral foramen, significantly reduced mechanical allodynia, and microanalysis showed a significant suppression of EAAs and citrulline release. The antiallodynic effect of PRF was observed the day following CFA injection and maintained for 7 days. We showed that PRF administered adjacent to the dorsal root ganglion suppresses the release of EAAs, which may account for the PRF antiallodynic properties observed in adjuvant-induced inflammation.
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The present study focuses on the neurostructural foundations of the human personality. In a large sample of 227 healthy human individuals (168 women and 59 men), we used MRI to examine the relationship between personality traits and both regional gray and white matter volume, while controlling for age and sex. Personality was assessed using the German version of the NEO Five-Factor Inventory that measures individual differences in the 'Big Five of Personality': extraversion, neuroticism, agreeableness, conscientiousness, and openness to experience. ⋯ However, among others, higher conscientiousness scores correlated significantly with reductions in regional white matter volume in different brain areas, including the right insula, putamen, caudate, and left fusiformis. These correlations were driven by the female subsample. The present study suggests that many results from the literature on the neurostructural basis of personality should be reviewed carefully, considering the results when the sample size is larger, imaging methods are rigorously applied, and sex-related and age-related effects are controlled.