Supplementation with Combined Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 Across Development Reveals Sex Differences in Physiological and Behavioural Effects of Western Diet in Long-Evans Rats.

The gut microbiome affects various physiological and psychological processes in animals and humans, and environmental influences profoundly impact its composition. Disorders such as anxiety, obesity, and inflammation have been associated with certain microbiome compositions, which may be modulated in early life. In 62 Long-Evans rats, we characterised the effects of lifelong Bifidobacterium longum R0175 and Lactobacillus helveticus R0052 administration-along with Western diet exposure-on later anxiety, metabolic consequences, and inflammation. We found that the probiotic formulation altered specific anxiety-like behaviours in adulthood. We further show distinct sex differences in metabolic measures. In females, probiotic treatment increased calorie intake and leptin levels without affecting body weight. In males, the probiotic seemed to mitigate the effects of Western diet on adult weight gain and calorie intake, without altering leptin levels. The greatest inflammatory response was seen in male, Western-diet-exposed, and probiotic-treated rats, which may be related to levels of specific steroid hormones in these groups. These results suggest that early-life probiotic supplementation and diet exposure can have particular implications on adult health in a sex-dependent manner, and highlight the need for further studies to examine the health outcomes of probiotic treatment in both sexes.

Performing various perceptual actions elicits differentiable P300 responses.

Several studies have explored the differentiation of visual action verbs (e.g., see, perceive, and notice). The vast number and variety to choose from, along with a common understanding between the meanings of the words, suggests that they may represent measurable differences in perceptual processing. The present study investigated how manipulating the visual action verb embedded into a common instruction could produce either differentiable electrophysiological or behavioral effects, or possibly both. It was hypothesized that the P300 component elicited during an oddball task would differ depending on the visual action that participants had been instructed to perform. Results support this hypothesis, but suggest that response bias also could contribute to action performance. When participants were asked to 'sense' deviants in an oddball task, the P300 differed in amplitude compared to when they were asked to 'distinguish' the deviants. In addition, participants displayed varying response times for the instructions 'notice' versus 'view', 'distinguish' versus 'sense', and 'notice' versus 'sense'. When considering the behavioral and ERP results together, we can conclude that response biases and perceptual cognitive processing both contribute to how identical stimuli can be processed depending on the visual action performed.