Maurice L. Sipos

Dose-response curves and time-course effects of selected anticholinergics on locomotor activity in rats

Abstract  Rationale: In order to facilitate direct comparisons of anticholinergic drug effects on activity, nine drugs were tested in one laboratory using a standardized procedure. Objective: The present study compared the effects of aprophen hydrochloride, atropine sulfate, azaprophen hydrochloride, benactyzine hydrochloride, biperiden hydrochloride, diazepam, procyclidine hydrochloride, scopolamine hydrobromide, and trihexyphenidyl hydrochloride on activity levels in rats. Methods: Both fine motor activity (reflecting smaller movements) and ambulatory activity (reflecting larger movements) were recorded for 23 h following drug administration in food-restricted rats. All drugs were administered during the light period of the photocycle. Results: Atropine, azaprophen, biperiden, scopolamine, and trihexyphenidyl increased both ambulations and fine motor activity significantly during the first hour post-injection, but the increased activity levels returned to vehicle control levels within 2–6 h post-injection. Benactyzine and procyclidine only increased fine motor activity significantly above vehicle control levels and activity levels returned to vehicle control levels within 2–3 h. Finally, aprophen and diazepam generally did not increase measures of activity significantly above vehicle controls at the dose ranges examined. Conclusions: Based on potencies relative to scopolamine, the potency of the drugs could be ranked as follows: scopolamine > trihexyphenidyl > biperiden > azaprophen > procyclidine > benactyzine > atropine > aprophen. The comparison of drug effects on activity may be useful in selecting anticholinergic drug therapies with a minimal range of side effects. In addition, these data may reduce the number of anticholinergic drugs that need to be tested in comparison studies involving more complex behavioral tests.

Threat-Related Attention Bias Variability and Posttraumatic Stress

OBJECTIVE Threat monitoring facilitates survival by allowing one to efficiently and accurately detect potential threats. Traumatic events can disrupt healthy threat monitoring, inducing biased and unstable threat-related attention deployment. Recent research suggests that greater attention bias variability, that is, attention fluctuations alternating toward and away from threat, occurs in participants with PTSD relative to healthy comparison subjects who were either exposed or not exposed to traumatic events. The current study extends findings on attention bias variability in PTSD. METHOD Previous measurement of attention bias variability was refined by employing a moving average technique. Analyses were conducted across seven independent data sets; in each, data on attention bias variability were collected by using variants of the dot-probe task. Trauma-related and anxiety symptoms were evaluated across samples by using structured psychiatric interviews and widely used self-report questionnaires, as specified for each sample. RESULTS Analyses revealed consistent evidence of greater attention bias variability in patients with PTSD following various types of traumatic events than in healthy participants, participants with social anxiety disorder, and participants with acute stress disorder. Moreover, threat-related, and not positive, attention bias variability was correlated with PTSD severity. CONCLUSIONS These findings carry possibilities for using attention bias variability as a specific cognitive marker of PTSD and for tailoring protocols for attention bias modification for this disorder.

Behavioral Effects Of 8-OH-DPAT in Chronically Stressed Male and Female Rats

The present study tested the hypothesis that chronic stress desensitizes serotonergic 5-HT(1A) receptors and alters behavioral changes following 5-HT(1A) agonist administration. Eating, acoustic startle response (ASR), and locomotor activity were measured in stressed and nonstressed male and female rats after 8-OH-DPAT administration. Stressed rats were paired and stressed by around-the-clock intermittent foot shock. Controllable stress (CS) rats could avoid/terminate shock for themselves and their yoked partners by pulling a ceiling chain, whereas their partners, the uncontrollable stress (UCS) rats, could not. Rats earned their entire daily ration of food by pressing a lever. In previous experiments, this paradigm was stressful, but not debilitating and rats continued to eat, groom, sleep, and avoid/escape greater than 99% of shock trials. Locomotor activity and ASR were measured in the present study after saline and 8-OH-DPAT administration (0.25 mg/kg, IP) before, 24 h, and 72 h after shock onset. 8-OH-DPAT only decreased food intake significantly in male and female rats after the first administration. Stress decreased food intake in both the CS and UCS rats, with UCS rats eating the least. However, the effects of stress and 8-OH-DPAT were not additive. 8-OH-DPAT significantly increased peak startle amplitude at 100 and 120 dB, and decreased latency to peak startle amplitude at 100 dB in male and female rats. In contrast, 8-OH-DPAT did not alter percent prepulse inhibition (%PPI) at 100 dB, but significantly decreased %PPI in males but not females at 120 dB. Stress did not have a consistent effect on ASR, but reduced %PPI in males, but not females. Neither stress nor 8-OH-DPAT significantly altered locomotor activity. Although the results do not show an increased sensitivity to 8-OH-DPAT in stressed rats, the unexpectedly weak effects of 8-OH-DPAT alone on the behavioral measures chosen limits the conclusions that can be drawn.

Sleep leadership in high-risk occupations: An investigation of soldiers on peacekeeping and combat missions.

Individuals in high-risk occupations (e.g., military service) often report physical, psychological, and organizational problems. Although leaders can partially buffer their subordinates against these problems, the impact of established leadership skills appears limited, especially in high-risk occupations. Thus, building on recent theories of domain-specific leadership, we examined whether leadership focused on the specific domain of sleep might be negatively associated with some specific problems facing individuals in high-risk occupations, beyond their relationship with general leadership. Studying military personnel on peacekeeping and combat deployments, we predicted that “sleep leadership” would be negatively associated with sleep problems (physical), depressive symptoms (psychological), and negative climate (organizational), and that sleep would mediate the relationship between sleep leadership and the psychological and organizational problems. Results were generally supportive, contributing to theories of domain-specific leadership by showing that sleep-focused leader behaviors may go beyond general leadership behaviors, relating directly to the problems facing individuals in high-risk occupations.

Behavioral Health Leadership: New Directions in Occupational Mental Health

The impact of stress on mental health in high-risk occupations may be mitigated by organizational factors such as leadership. Studies have documented the impact of general leadership skills on employee performance and mental health. Other researchers have begun examining specific leadership domains that address relevant organizational outcomes, such as safety climate leadership. One emerging approach focuses on domain-specific leadership behaviors that may moderate the impact of combat deployment on mental health. In a recent study, US soldiers deployed to Afghanistan rated leaders on behaviors promoting management of combat operational stress. When soldiers rated their leaders high on these behaviors, soldiers also reported better mental health and feeling more comfortable with the idea of seeking mental health treatment. These associations held even after controlling for overall leadership ratings. Operational stress leader behaviors also moderated the relationship between combat exposure and soldier health. Domain-specific leadership offers an important step in identifying measures to moderate the impact of high-risk occupations on employee health.

The Impact of Insufficient Sleep on Combat Mission Performance

ABSTRACT A significant concern for the U.S. military is the inability of service members to obtain sufficient sleep during combat deployments as it directly affects the health and readiness of the force. The performance deficits that result from sleep loss are well known, and the implications of such deficits include increased risk for accidents and mistakes. This study assessed the relationship between average daily sleep duration and combat mission performance. Anonymous survey data were collected from U.S. Army combat platoons deployed to Afghanistan in 2013. Participants reported getting between five and six hours of sleep per day, and 14.6% of soldiers reported accidents that affected the mission, with half of these (51%) attributed to sleepiness. A logistic regression showed a significant association between the number of hours of sleep and the incidence of accidents or mistakes that affected the mission. In addition, 34.1% of soldiers reported falling asleep on guard duty, which was also significantly associated with the number of hours of sleep per day. This is the first report to our knowledge on the relationship between sleep and performance in a deployed environment and confirms that soldiers obtain significantly less sleep than the recommended seven to eight hours per day.

Behavioral Health Adjustment in Reserve Component Soldiers During a Noncombat Deployment to Africa

This study benchmarked rates of mental health problems, adjustment difficulties, and perceptions of unit climate among 505 U.S. soldiers (primarily National Guard) deployed to the Horn of Africa in 2012. In addition, the study examined whether differences across these outcomes exist between combat veterans (n = 239) and noncombat veterans (n = 242). Rates of mental health problems among soldiers on this noncombat deployment were lower than rates typically found among soldiers on combat deployments. Furthermore, soldiers without previous combat experience had lower rates of mental health problems and aggression than combat veterans. Similar differences were evident when adjustment difficulties and unit climate variables were compared. Although combat veterans could be valuable in training new soldiers, the results of this study indicate that combat veterans may need more targeted resources to facilitate their adjustment if they are to be optimally utilized.

Postdeployment behavioral health screening: face-to-face versus virtual behavioral health interviews.

Virtual behavioral health (VBH) services are used frequently to address the high demand for behavioral health (BH) services in the military. Few studies have investigated the relationship between the use of VBH services and BH outcomes or preferences for the use of VBH technologies. In this article, we evaluated BH interviews conducted via video teleconferencing (VTC) or face-to-face in terms of BH symptoms, satisfaction rates, stigma, barriers to care, and preferences for future use of BH care. Soldiers (n = 307) from the headquarters element of an operational unit were surveyed 4 months following a 12-month deployment to Iraq. There were no significant differences in satisfaction rates based on interview modality, but significantly more soldiers preferred face-to-face interviews over VTC interviews in the future. Soldiers who preferred face-to-face interviews also reported higher levels of anxiety and depression symptoms than those who preferred VTC interviews. No significant age differences were found in terms of interview modality satisfaction or preference. Soldiers with greater deployment experience were more likely to report that they would not like using VTC if seeking BH care in the future than soldiers with less deployment experience. These findings highlight the importance of promoting choice in type of BH interview modality.

Assessment of an Alternative Postdeployment Reintegration Strategy With Soldiers Returning From Iraq

The present study examined behavioral health outcomes, risk behaviors, aggression, alcohol misuse, marital satisfaction, and attitudes toward reintegration associated with an alternative, front-loaded reintegration strategy compared with a more standardized reintegration process in soldiers returning from combat deployments. The type of reintegration strategy used did not predict differences in posttraumatic stress disorder (PTSD) symptoms, alcohol misuse, aggression, and marital satisfaction, although slightly higher reports of risk behaviors were found in the unit using the standard reintegration approach even after controlling for demographic covariates and combat exposure. These findings may help guide leadership when making decisions regarding reintegration approaches in the future.

Professional stress and burnout in U.S. Military medical personnel deployed to Afghanistan

BACKGROUND Studies of medical staff members have consistently documented high levels of burnout compared to those in other professions. Although there are studies of burnout in military medical staff, there are gaps in understanding the experience of medical staff while they are deployed and few occupationally-related factors associated with decreased burnout have been identified in this population. PURPOSE To assess work-related variables accounting for burnout over and above rank, post-traumatic stress disorder (PTSD) symptoms, and professional stressors in the deployed environment. METHODS U.S. military medical staff members were surveyed in Afghanistan. The survey assessed burnout (emotional exhaustion and depersonalization), PTSD symptoms, perception of professional stressors, self-care behaviors, taking care of team members (team care), general leadership, and health-promoting leadership. Participants provided informed consent under a protocol approved by the institutional review board at Walter Reed Army Institute of Research, and coordinated through the Washington Headquarters Service and the Joint Casualty Care Research Team located in Afghanistan. A total of 344 individuals provided their consent (83.3%) and completed the survey. RESULTS Correlations found significant positive relationships between perception of professional stressors and levels of burnout. Significant negative correlations were found between burnout and self-care, team care, general leadership, and health-promoting leadership. Regression analyses found self-care and team care accounted for less burnout even after controlling for rank, PTSD symptoms, and professional stressors. Health-promoting leadership accounted for less burnout even after controlling for these same covariates and general leadership as well. CONCLUSION Although a cross-sectional survey, results provide three specific directions for reducing burnout in deployed medical staff. By emphasizing self-care, team care, and health-promoting leadership, policy makers, researchers, and leaders can address factors that influence burnout in this, and other occupational contexts. In addition, the constructs of team care and leadership offer novel contributions to the study of burnout in medical personnel.