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Intensive repeated momentary diary techniques, such as the experience sampling method (ESM), place considerable burden on study participants by repeatedly prompting them to fill in a questionnaire several times throughout the day. The objective of this study was to investigate the level of disturbance reported by participants and predictors thereof using a pooled dataset of seven ESM studies including 1319 healthy participants and individuals with different mental health conditions. All studies used a design of 10 prompts per day over the course of 4 to 6 days. Participants reported no disturbance at 37% of the measurement occasions and the overall level of disturbance was relatively low. Also, clinical samples did not report significantly different levels of disturbance compared to the healthy participants. However, higher levels of disturbance were found for later study days, in the morning, and on weekends. Also, younger participants reported feeling more disturbed by the prompts. In terms of momentary states, higher levels of activity, activity stress, and tiredness were associated with higher disturbance. Also, participants experienced more disturbance when in company compared to when alone, and the level of disturbance increased when in company with less familiar people. Our findings suggest that studies using high-frequency ESM protocols can be used in mental health research, but researchers should be aware of the possible disturbance caused by their research design.

Companion animals have been identified as a unique source of social support and as contributors to mental wellbeing. This study uses the Experience Sampling Method to test whether this effect is due to stress-buffering. A total of 159 dog and cat owners responded to a series of randomly scheduled questionnaires on their smartphones. At each measurement moment, they reported in whether a pet is present at that moment and to what extent they have interacted with the pet. They also reported on stressful activities and events and on their current positive (PA) and negative (NA) affect. Multilevel regression analyses showed that when a companion animal was present (vs. absent) the negative association between stress and PA is less pronounced (event stress: B = 0.13, p = 0.002, 95% CI = 0.05, 0.21 activity stress: B = 0.08, p &lt, 0.001, 95% CI = 0.04, 0.12). No additional main effect was revealed when tested in a subsample of records that reported low or no stress. Main effects were found for the presence of a companion animal on negative affect (B = 0.08, p &lt, 0.001, 95% CI = 0.12, 0.05) and for interacting with a companion animal on positive affect (B = 0.06, p &lt, 95% CI = 0.04, 0.08). This shows that the presence of a companion animal buffers against the negative consequences of stress on positive affect, indicating stress-buffering as a mechanism behind the pet-effect. It is, however, not the only mechanism and more research is required to further elucidate how companion animals contribute to human wellbeing.

A water-soluble chicken extract is popularly consumed as a traditional health food. The studies made revealed that it could increase the survival time and inhibit the increase of locomotor activity in rats loaded with food-deprived activity stress. The mechanism for this might be related to an elevation of the brain histamine level, and the active ingredient, carnosine, might contribute to this effect.

Although past research has indicated that stress and the accompanying increase in glucocorticoids compromises hippocampal neurons, little is known about the effect of stress on hippocampal glial cells. In the current study, male rats were exposed to activity-stress (A-S) for six days; this comprised housing with an activity wheel and restricted access (1h/day) to food. Physiological data (e.g., relative adrenal and thymus weights, gastric ulceration) suggested that the A-S rats experienced more stress than pair-fed (no wheel) and control (fed ad libitum, no wheel) rats. Whereas stress did not influence the quantitative morphology of glial fibrillary acidic protein (GFAP)-immunoreactive cells, a semi-quantitative analysis revealed that the A-S rats had significantly more (30%) GFAP-immunoreactive cells in the hippocampal CA3 region than the control rats. Based on the present findings, it appears that the hippocampal astrocytic response to chronic stress may be similar to the response found in endangered, or challenged hippocampal environments, such as in ischemia.

The exercising woman with nutritional deficits and related menstrual irregularities is at risk of compromising long-term bone health, i.e., the female athlete triad. There is no animal model of the female athlete triad. The purpose of this study was to examine long-term energy restriction in voluntary wheel-running female rats on estrous cycling, bone mineral content, and leptin levels. Twelve female Sprague-Dawley rats (age 34 days) were fed ad libitum and given access to running wheels during an initial 14-wk period, providing baseline and age-related data. Daily collection included dietary intake, body weight, estrous cycling, and voluntary running distance. At 4 mo, rats were randomized into two groups, six restrict-fed rats (70% of ad libitum intake) and six rats continuing as ad libitum-fed controls. Energy intake, energy expenditure, and energy availability (energy intake − energy expenditure) were calculated for each animal. Serum estradiol and leptin concentrations were measured by RIA. Femoral and tibial bone mineral density and bone mineral content (BMC) were determined by dual-energy X-ray absorptiometry. Restrict-fed rats exhibited a decrease in energy availability during Weight Loss and Anestrous phases ( P = 0.002). Compared with controls after 12 wk, restrict-fed rats showed reduced concentrations of serum estradiol ( P = 0.002) and leptin ( P = 0.002), lower ovarian weight ( P = 0.002), and decreased femoral ( P = 0.041) and tibial ( P = 0.05) BMC. Decreased energy availability resulted in anestrus and significant decreases in BMC, estrogen and leptin levels, and body weight. Finally, there is a critical level of energy availability to maintain estrous cycling.

Chipmunks were allowed access to a running wheel and fed 1½ h each day. After 13 days of restricted feeding, all activity animals had died and postmortem pathology revealed extensive lesions of the glandular stomach. Food-yoked control animals, not allowed to exercise, very rarely died and showed minimal signs of stomach pathology when autopsied. Circadian running patterns of activity animals indicated a marked increase in diurnal running during restricted feeding. Results indicate that the activity-stress procedure is capable of producing stomach ulcers in a wild animal species.

Rats were given d-amphetamine alone, placebo or d-amphetamine and food. They were then placed in the activity-stress ulcer paradigm, involving continuous access to a running wheel while being fed for only 1 hr. per day. Animals given d-amphetamine only ran more and died significantly sooner than animals in any other group. These rats also displayed significantly more gastric glandular ulcers than rats in any other group. Rats given d-amphetamine and food exhibited increased running but did not die sooner and displayed ulceration comparable to placebo rats. It appears that neither restricted feeding nor increased running wheel activity is a sufficient cause of activity-stress ulcers; rather, the combined interaction. of both of these variables appears to produce the observed gastric damage.

Rats were either group-housed, four rats per cage, or housed singly for 6 weeks. Subgroups were subsequently exposed to a daily 3-min 1.25-mA grid shock for 5 days. The rats were then housed in running-wheel activity cages and, following a 4-day free-feeding period, were fed only 1 h daily for 20 days. Group-housed rats had more ulcers, but the previously reported protective effect of preshock was not observed in this study.

In order to examine the susceptibility of Brattleboro rats to self-starvation and activity stress, as evidenced by ulcer formation, four conditions were studied: (1) ad-lib access to food and water in an individual home cage, (2) ad-lib access to food and water in an activity-wheel cage, (3) ad-lib access to water and 1-h access to food in an individual home cage, and (4) ad-lib access to water and 1-h access to food each day in an activity-wheel cage. In the first two conditions, neither Brattleboro nor control animals developed ulcers. In the third condition, some rats in each group developed pits in the glandular portion of the stomach. Significant differences appeared in the fourth condition. Brattleboro rats developed more stomach pathology in both the nonglandular and glandular portions of the stomach than controls. The results were not due to variations in running behavior. The data indicate that the lack of vasopressin or physiological results of this deficit render Brattleboro rats more sensitive to self-starvation and activity stress than control animals.

Rats housed in running-wheel activity cages and fed 1 h daily exhibited excessive running and subsequently died revealing large stomach ulcers. However, prior experience with a 1-h feeding schedule for 15 days before exposure to the activity-stress procedure did significantly extend survival time. A second study illustrated that feeding schedules of.5, 1.0, 1.5, or 2.0 h daily did not yield differences in terms of stomach ulcers or survival time, but a 3-h daily feeding did significantly reduce ulcer incidence and increase survival time.

Rats were housed in activity cages and fed 1 h daily. When these rats died, wet and dry weights were obtained for adrenals, spleen, liver, kidney, heart, stomach rumen, and stomach body. Most activity rats, as compared to food-yoke control and home-cage control rats, had lesions in the glandular stomach. Adrenal and heart weights suggested that activity rats had been subjected to some degree of stress. Characteristic starvation effects, such as rumenal lesions and edema of stomach tissue, were not observed in activity rats.

Rats were housed in standard activity cages and fed 1 h each day. One group of activity rats were fed in their activity cages, and another group of activity rats were fed in the colony home cages in which they resided before being moved to the activity wheel. The latter operation was designed to eliminate novelty stress inherent in the activity wheel environment which would suppress feeding. However, home cage feeding rats ate less than control rats, and had as many ulcers as activity rats fed in the activity wheel. Novelty stress, as defined by this study, did not contribute significantly to the development of the activity-stress ulcer.

Hamsters were fed for 11/2 h each day during the dark phase of an inverted day/night cycle and allowed access to an exercise wheel. At autopsy, all animals revealed lesions of the glandular stomach, while food-yoked control hamsters treated similarly, but not having an activity wheel, remained free of stomach pathology. Results indicate that this procedure is capable of reliably producing stomach lesions in this species if certain species-specific behaviors are first acknowledged.

Eighteen rats, 60 days old, and 18 rats, 110 days old, were housed in standard activity cages and fed 1 h each day for 21 days. Ten rats, 60 days old, and five rats, 110 days old, died before the end of the experiment. All rats that died revealed extensive lesions in glandular portions of the stomach. Control rats, housed in standard cages and also fed 1 h each day, did not die. Experimental rats that died were more active than experimental rats that survived, and ate less than survivors and normal control rats. This technique is proposed as a new animal model for studying gastrointestinal pathology.