Physiology & Behavior最新文献

Aim: Due to the widespread use of artificial lighting in modern workplaces, exposure to blue light is becoming increasingly common. Blue light, known for its shorter wavelength and higher energy, has been linked to both positive and negative effects on cognitive functions and well-being.

Objective: This systematic review explores the impact of blue light exposure on cognitive performance and sleep in various workplace settings.

Material and methods: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Using predefined inclusion and exclusion criteria, the team searched three reputable databases (PubMed, Web of Science, and Scopus). Two authors independently screened the search results and the three other authors performed the data extraction and validation from the selected documents. The quality of the articles was assessed using the quality assessment checklist provided by The Joanna Briggs Institute (JBI).

Results: From an initial set of 63 articles, 29 documents met the inclusion criteria. The findings reveal that blue light, particularly at high color temperatures and intensities, enhances cognitive functions such as attention, alertness, and reaction time. However, its effects on memory and sleep were more variable. Exposure to blue-enriched light was consistently associated with improved workplace performance, although some studies reported a mixed or insignificant impact.

Conclusion: This review underscores the potential benefits of blue light in workplace settings, particularly for enhancing attention and reaction times. However, variations in study outcomes suggest the need for standardized lighting interventions and further research on its long-term cognitive impacts.

Abstract.

Objectives: This study investigated the effects of environmental enrichment (EE) on the behavior and histological alterations of rats with barrel cortex damage.

Methods: Forty-eight adult male rats were divided into Control (Ctrl), Lesion, Lesion+EE.S (Lesion+Standard Enriched Environment, and Lesion+EE.T (Lesion+Tactile Enriched Environment) groups. The animals were first anesthetized, and then, a cold lesion model was performed on the parietal cortex. After surgery, the rats were exposed to a standard enriched environment or enriched environment with tactile for 30 days. Their cognitive behaviors were assessed using an open field, novel texture discrimination, and Morris water maze (MWM) tests. In addition, a histological investigation was conducted to determine the degree of degeneration of hippocampal and somatosensory cortex neurons.

Results: The results demonstrated that rats with barrel cortex lesions revealed impairments in novel texture discrimination and MWM tests (P<0.001). Moreover, lesions increased neuronal degeneration in rats' barrel cortex and hippocampus (P< 0.001). Environmental enrichment improved behavioral deficits and decreased neuronal degeneration in the barrel cortex and hippocampus of rats with barrel cortex lesions (P<0.05).

Conclusion: The current study suggests that barrel cortex lesions create cognitive and behavioral deficits and neural degeneration in the barrel cortex and hippocampus; however, environmental enrichment could reverse these impairments.

Social isolation profoundly impacts motivated behavior and neural plasticity. While the effects of acute and chronic social isolation have been extensively studied, the consequences of intermittent isolation during adulthood, particularly relevant to modern lifestyles, remain poorly understood. This study investigated the impact of intermittent social isolation (ISI) on social behavior and brain activation in adult male mice. Compared to group-housed controls, ISI males exhibited heightened social investigation and increased social interaction, reminiscent of craving-like behaviors. Intriguingly, this enhanced social investigation was accompanied by impaired social recognition memory in a three-chamber sociability test. Furthermore, ISI induced distinct patterns of neural activation in brain regions governing social processing, including the paraventricular nucleus of the hypothalamus, the intermediate part of lateral septum, the paraventricular nucleus of the thalamus, and the thalamic periventricular gray. Notably, ISI did not affect anxiety-like behaviors or spatial memory, emphasizing its specific impact on social domains. These findings demonstrate that ISI during adulthood selectively enhances social investigation while disrupting social memory in male mice, possibly mediated by distinct neural circuits. Understanding the neurobiological mechanisms underlying these effects may inform interventions for individuals experiencing social isolation, an increasingly prevalent phenomenon in modern society.

Exposure to stressors has been shown to dysregulate motivated behaviors in a bidirectional manner over time. The relationship between stress and motivation is relevant to psychological disorders, including depression, binge eating, and substance abuse; however, this relationship is not well characterized, especially in females, despite their increased risk of these disorders. Social defeat stress is a common model to study stress-induced motivation changes, however, historically this model excluded females due to lack of female-to-female aggression and unreliable male-to-female aggression. Additionally, changes in motivation are often assessed well after stress exposure ends, potentially missing or occluding changes to motivation during stress. Recently, the chronic non-discriminatory social defeat stress (CNSDS) model has demonstrated social defeat of male and female C57BL/6J mice by exposing both mice to an aggressive male CD-1 mouse simultaneously. Here we use this model to directly compare changes in the motivated behavior of male and female mice during and following chronic stress. We hypothesized that motivated behavioral responses would be dysregulated during stress and that the effects would worsen as the stress exposure continued. To monitor motivated behavior, mice had access to a Feeding Experimental Device.3 (FED3), a home cage device for operant responding. Operant responding was monitored prior to, during, and after stress by measuring nose pokes for sucrose pellets on a modified progressive ratio schedule of reinforcement. Our results demonstrated divergent behavioral outcomes between males and female mice in response to stress; where male mice increased motivated behavior during stress only, whereas female mice exhibited a decrease in motivation during and after stress. This study highlights the need to investigate the effects of stress-induced motivation over time, as well as the increased need to understand differences in the stress response in females.

Alcohol use disorder (AUD) is a condition with multifactorial causes, including biopsychosocial factors. Childhood exposure to stress may increase susceptibility to AUD in adulthood. Despite its significance, the interaction between stress and AUD remains unclear. This study investigated whether maternal separation stress (MS) would change epigenetic marker levels in mice's amygdala and whether these changes correlate with increased ethanol consumption and preference in adulthood. C57BL/6J pups in the maternal separation group were removed from their nests for 3 hours daily from postnatal day (PND) 1 to PND 14. Control animals remained under maternal care. All litters were weaned on PND 21, and on PND 60, mice were subjected to a two-bottle choice protocol using one bottle containing water and another containing ethanol in crescent concentrations (5%, 10%, 15%, and 20% w/v; every three days) for 8 hours daily. Following a 3-day withdrawal, a reinstatement test using the two-bottle choice paradigm was conducted. Afterward, the amygdala was dissected for analysis of acetylated histones, H3 dimethylated in lysine 9, Sirtuin-1, and DNA methyltransferases-1 by Western Blotting. Results demonstrated that exposure to maternal separation during childhood increased mice ethanol preference but not consumption during adulthood. We also observed no alterations in the levels of the epigenetic markers analyzed. These results support the hypothesis that maternal separation exposure can influence ethanol-related behaviors in the later phases of development.

Chemosensory learning is a lifelong process of acquiring perceptual expertise and semantic knowledge about chemical stimuli within the everyday environment. In the research context, it is usually simulated using olfactory training, which typically involves repeated exposure to a set of odors over a period of time. Following olfactory training, enhanced olfactory performance has been observed in adults, and similar evidence is beginning to emerge in children. However, the literature is scant concerning the effects of interventions that more closely resemble how chemosensory experience is acquired in daily life. Since children's chemosensory ecology appears to play a crucial role in olfactory development, we investigated whether engaging in activities that stimulate the chemical senses enhances olfactory performance and metacognition. To this end, we invited 20 children aged 9-11 years to participate in teacher-assisted after-school activities for 30-60 minutes a day for six weeks. During the odd weeks, the children appraised herbal and spice blends and used them to prepare dishes and make beauty products. During the even ones, they explored the city by smellwalking and created smellscape maps. The educational outcomes were evaluated using the Sniffin' Sticks test for odor identification and discrimination and the Children's Personal Significance of Olfaction. Bayesian analyses did not reveal any compelling evidence in support of the alternative hypothesis that children in the chemosensory education group outperform those in the comparison group at the post-test. Rates of reliable increase but also decrease in performance on the Sniffin' Sticks identification and discrimination tests were similar in both groups. We corroborated the previous findings regarding girls' and older children's greater proficiency at identifying odors and the female keener interest in the sense of smell. We offer several practical suggestions researchers may want to consider to tailor their research protocols to reflect more closely the broader context in which chemosensory learning takes place and better capture the nuanced outcomes of such interventions.

This study aimed to evaluate the influence of rat strain in expression of autonomic and cardiovascular changes during acute exposure to restraint stress, as well as in habituation of these physiological responses upon repeated exposure to restraint. For this, blood pressure, heart rate (HR) and sympathetically-mediated cutaneous vasoconstriction were assessed in Wistar (control strain), Long-Evans, Holtzman and spontaneously hypertensive (SHR) rats during acute or 10^th 60-min session of restraint stress. We observed that HR returned faster to baseline values during recovery of the acute session of restraint in Long-Evans and SHR rats in relation to Wistar, thus indicating shorter tachycardia in these strains. Long-Evans also presented enhanced sympathetically-mediated cutaneous vasoconstriction to acute restraint stress. Habituation of the tachycardiac response evidenced as a faster HR return to baseline values during recovery of the 10^th restraint session in relation to acute stress was similarly identified in both Wistar and Holtzman rats. However, cardiovascular changes were similarly evoked during acute and 10^th restraint stress session in SHR and Long-Evans rats. Taken together, these findings indicate that both cardiovascular responses during acute stress and habituation of these physiological adjustments upon repeated exposure to the same stressor are strain-dependent. Differences were mainly observed in Long-Evans and SHR strains, whereas Holtzman rats seem to present similar autonomic and cardiovascular changes in relation to Wistar rats.

A system is described for the semi-automated collection of fluid bottle, food jar, and rodent body weights. Items are labeled with barcodes, which are scanned by a Macintosh application connected via USB to a scale. Body weights are collected in the animal room by an iPad application connected to a Bluetooth scale. Simple summary statistics are automatically calculated, and data are stored with experiment metadata in a cloud database. Up-to-date graphs of the data are rendered by a web application from any browser, from which data can be downloaded for further analysis. Such a system makes ingestive behavior experiments more accurate, rapid, and higher throughput.

Depression triggered by harmful stress in adolescents is a common phenomenon that can lead to serious social problems. Its treatment is still frustrating in the clinic. We reported the phenomenon that a 12-day chronic unpredictable stress (CUS), starting on postnatal day 28, led to a significant decrease in the number of microglia in the dentate gyrus of the hippocampus in adult mice. Reversal of this decline by a single injection of low-dose lipopolysaccharide (LPS), a classical immunostimulant, could rapidly reverse the depression-like behaviors induced by 12 days of CUS stimulation during adolescence. In the dose-dependent experiment, a single injection of LPS at doses of 75 and 100 μg/kg, but not at doses of 25 and 50 μg/kg, produced an antidepressant effect in mice exposed to 12-day CUS during adolescence. The time-dependent experiment showed that the antidepressant effect of the single LPS injection (100 μg/kg) occurred at time points 5 and 8 hours, but not 3 hours after LPS injection. The antidepressant effect of the single LPS injection (100 μg/kg) lasted for at least 7 days, and 14 days after the single LPS injection, a repeated injection could still induce the depressed mice to develop an antidepressant phenotype. Furthermore, inhibition of microglia by minocycline or depletion of microglia by PLX3397 was found to prevent the antidepressant effect of the single LPS injection. These results suggest that reversing the decline of microglia in the dentate gyrus may be a potential strategy for the treatment of depression induced by harmful stress in adolescents.