Alcohol Perceptions and Behavior in a Residential Peer Social Network

Personalized normative feedback is a recommended component of alcohol interventions targeting college students. However, normative data are commonly collected through campus-based surveys, not through actual participant-referent relationships. In the present investigation, we examined how misperceptions of residence hall peers, both overall using a global question and those designated as important peers using person-specific questions, were related to students’ personal drinking behaviors. Participants were 108 students (88% freshman, 54% White, 51% female) residing in a single campus residence hall. Participants completed an online baseline survey in which they reported their own alcohol use and perceptions of peer alcohol use using both an individual peer network measure and a global peer perception measure of their residential peers. We employed network autocorrelation models, which account for the inherent correlation between observations, to test hypotheses. Overall, participants accurately perceived the drinking of nominated friends but overestimated the drinking of residential peers. Consistent with hypotheses, overestimating nominated friend and global residential peer drinking predicted higher personal drinking, although perception of nominated peers was a stronger predictor. Interaction analyses showed that the relationship between global misperception and participant self-reported drinking was significant for heavy drinkers, but not non-heavy drinkers. The current findings explicate how student perceptions of peer drinking within an established social network influence drinking behaviors, which may be used to enhance the effectiveness of normative feedback interventions

Enrollment and Assessment of a First-Year College Class Social Network for a Controlled Trial of the Indirect Effect of a Brief Motivational Intervention

Heavy drinking and its consequences among college students represent a serious public health problem, and peer social networks are a robust predictor of drinking-related risk behaviors. In a recent trial, we administered a Brief Motivational Intervention (BMI) to a small number of first-year college students to assess the indirect effects of the intervention on peers not receiving the intervention. Objectives: To present the research design, describe the methods used to successfully enroll a high proportion of a first-year college class network, and document participant characteristics. Methods: Prior to study enrollment, we consulted with a student advisory group and campus stakeholders to aid in the development of study-related procedures. Enrollment and baseline procedures were completed in the first six weeks of the academic semester. Surveys assessed demographics, alcohol use, and social network ties. Individuals were assigned to a BMI or control group according to their dormitory location. Results: The majority of incoming first-year students (1342/1660; 81%) were enrolled (55% female, 52% nonwhite, mean age 18.6 [SD = 0.51]). Differences between the intervention and control group were noted in alcohol use, but were in large part a function of there being more substance-free dormitory floors in the control group. Conclusions: The current study was successful in enrolling a large proportion of a first-year college class and can serve as a template for social network investigations

Do Misperceptions of Peer Drinking Influence Personal Drinking Behavior? Results From a Complete Social Network of First-Year College Students

This study considered the influence of misperceptions of typical versus self-identified important peers\u27 heavy drinking on personal heavy drinking intentions and frequency utilizing data from a complete social network of college students. The study sample included data from 1,313 students (44% male, 57% White, 15% Hispanic/Latinx) collected during the fall and spring semesters of their freshman year. Students provided perceived heavy drinking frequency for a typical student peer and up to 10 identified important peers. Personal past-month heavy drinking frequency was assessed for all participants at both time points. By comparing actual with perceived heavy drinking frequencies, measures of misperceptions of heavy drinking (accurately estimate, overestimate, underestimate) were constructed for both general and important peers. These misperceptions were then used as predictors of concurrent and prospective personal heavy drinking frequency and intentions using network autocorrelation analyses. The majority of students (84.8%) overestimated, 11.3% accurately estimated, and 3.9% underestimated heavy drinking among their general peers, whereas 42.0% accurately estimated, 36.9% overestimated, and 21.1% underestimated important peers\u27 heavy drinking. For both referents, overestimation of peer heavy drinking was associated with more frequent heavy drinking and higher drinking intentions at both time points. Importantly, the effects of underestimating and overestimating close peers\u27 drinking on personal alcohol use were significant after controlling for the influence of misperceptions of general peers\u27 heavy drinking. Close peers are a critical referent group in assessments related to social norms for young adult alcohol use. Implications for prevention and intervention are discussed

Posttraumatic Stress Disorder Symptoms Contribute to Staff Perceived Irritability, Anger, and Aggression After TBI in a Longitudinal Veteran Cohort: A VA TBI Model Systems Study

Objective To examine the relationship between staff perceived irritability, anger, and aggression and posttraumatic stress disorder (PTSD) in veterans with traumatic brain injury (TBI) of all severity levels. Design Longitudinal cohort design. Setting Veterans Affairs Polytrauma Transitional Rehabilitation Programs. Participants Veterans and service members with TBI of all severity levels enrolled in the Veterans Affairs Polytrauma Rehabilitation Centers’ Traumatic Brain Injury Model System national database (N=240). Interventions Not applicable. Main Outcome Measure Univariable and multivariable logistic regression modeling was used to examine the association between irritability, anger, and aggression and potential risk factors, including PTSD symptoms. Irritability, anger, and aggression was measured as a single construct using an item from the Mayo-Portland Adaptability Inventory-4 that was rated by program staff at admission and discharge from the inpatient rehabilitation program. PTSD symptoms were assessed using the PTSD Checklist–Civilian Version. Results PTSD symptoms uniquely predicted program staff-rated irritability, anger, and aggression at discharge even after controlling for severity of TBI, age, male sex, education, and annual earnings. The model explained 19% of the variance in irritability, anger, and aggression. Conclusions When TBI severity and PTSD symptoms were considered simultaneously in a sample of veterans, only PTSD symptoms predicted staff-rated irritability, anger, and aggression. Given the negative outcomes linked with irritability, anger, and aggression, veterans may benefit from assessment and treatment of PTSD symptoms within rehabilitation settings

Quantifying impacts of short-term plasticity on neuronal information transfer

Short-term changes in efficacy have been postulated to enhance the ability of synapses to transmit information between neurons, and within neuronal networks. Even at the level of connections between single neurons, direct confirmation of this simple conjecture has proven elusive. By combining paired-cell recordings, realistic synaptic modelling and information theory, we provide evidence that short-term plasticity can not only improve, but also reduce information transfer between neurons. We focus on a concrete example in rat neocortex, but our results may generalise to other systems. When information is contained in the timings of individual spikes, we find that facilitation, depression and recovery affect information transmission in proportion to their impacts upon the probability of neurotransmitter release. When information is instead conveyed by mean spike rate only, the influences of short-term plasticity critically depend on the range of spike frequencies that the target network can distinguish (its effective dynamic range). Our results suggest that to efficiently transmit information, the brain must match synaptic type, coding strategy and network connectivity during development and behaviour.Comment: Accepted for publication in Phys Rev E. 42 pages in referee format, 9 figure

Evolution of Irritability, Anger, and Aggression after Traumatic Brain Injury: Identifying and Predicting Subgroups

The current prospective, multi-center, longitudinal cohort study examined how veterans/service members (V/SM) changed in their irritability, anger, and aggression (IAA) scores from admission to discharge in post-acute rehabilitation settings. The goals were to identify trajectory subgroups, and explore if there were different predictors of the subgroups. V/SM (n = 346) from five Veterans Affairs TBI Model Systems Polytrauma Rehabilitation Centers participated. The sample was mostly men (92%) and identified as white (69%), black (13%), and other races (18%). Median age was 28 years, and 78% had sustained a severe TBI. Staff rated IAA at admission and discharge using the Mayo-Portland Adaptability Inventory-4 item#15. Four IAA trajectory subgroups were identified: (1) no IAA at admission or discharge (n = 89, 25.72%), (2) resolved IAA (n = 61, 17.63%), (3) delayed onset IAA (n = 31, 8.96%), and (4) persistent IAA (n = 165, 47.69%). Greater post-traumatic stress disorder (PTSD) symptoms were the only consistent predictor of belonging to all the subgroups who had IAA compared with the no IAA subgroup. We conclude that IAA had different trajectories after a TBI. The majority of V/SM had persistent impairment from IAA, a quarter of the sample had no impairment from IAA, and fewer participants had resolving or worsening IAA. Findings emphasize the importance of educating providers and family of the different ways and times that IAA can manifest after TBI. Timely diagnosis and treatment of PTSD symptoms during and after rehabilitation are critical treatment targets

The MeerTime Pulsar Timing Array -- A Census of Emission Properties and Timing Potential

MeerTime is a five-year Large Survey Project to time pulsars with MeerKAT, the 64-dish South African precursor to the Square Kilometre Array. The science goals for the programme include timing millisecond pulsars (MSPs) to high precision (< 1 $\mu$s) to study the Galactic MSP population and to contribute to global efforts to detect nanohertz gravitational waves with the International Pulsar Timing Array (IPTA). In order to plan for the remainder of the programme and to use the allocated time most efficiently, we have conducted an initial census with the MeerKAT "L-band" receiver of 189 MSPs visible to MeerKAT and here present their dispersion measures, polarization profiles, polarization fractions, rotation measures, flux density measurements, spectral indices, and timing potential. As all of these observations are taken with the same instrument (which uses coherent dedispersion, interferometric polarization calibration techniques, and a uniform flux scale), they present an excellent resource for population studies. We used wideband pulse portraits as timing standards for each MSP and demonstrated that the MeerTime Pulsar Timing Array (MPTA) can already contribute significantly to the IPTA as it currently achieves better than 1 $\mu$s timing accuracy on 89 MSPs (observed with fortnightly cadence). By the conclusion of the initial five-year MeerTime programme in July 2024, the MPTA will be extremely significant in global efforts to detect the gravitational wave background with a contribution to the detection statistic comparable to other long-standing timing programmes.Comment: Accepted to PASA. 27 figures. Data to be made available under the DOI 10.5281/zenodo.5347875 at the time of publicatio

Demographic and Mental Health Predictors of Arrests Up to 10 Years Post-Traumatic Brain Injury: A Veterans Affairs TBI Model Systems Study

OBJECTIVE: Examine rates and predictors of arrests in Veterans and Service Members (V/SM) who received inpatient rehabilitation for traumatic brain injury (TBI). SETTING: Veterans Administration (VA) Polytrauma Rehabilitation Centers. PARTICIPANTS: A total of 948 V/SM drawn from the VA TBI Model Systems cohort with arrest data up to 10 years post-TBI. DESIGN: Longitudinal cohort study; secondary analysis of pre-TBI characteristics predicting post-TBI arrests. MAIN MEASURES: Disclosure of arrests pre-TBI and up to10 years post-TBI. RESULTS: Thirty-six percent of the sample had been arrested prior to their TBI; 7% were arrested post-TBI. When considering all variables simultaneously in a multivariate model, pre-TBI mental health treatment (adjusted odds ratio [aOR] = 4.30; 95% confidence interval [CI]: 2.03-9.14), pre-TBI heavy alcohol use (aOR = 3.04; CI: 1.08-8.55), and number of follow-up interviews (aOR = 2.05; CI: 1.39-4.50) were significant predictors of post-TBI arrest. CONCLUSION: Arrest rates of V/SM prior to TBI were consistent with rates of arrest for people of similar ages in the United States. Post-TBI rates were lower for V/SM than published rates of post-TBI arrests in civilians with TBI. As part of rehabilitation planning for V/SM with TBI, providers should assess for preinjury mental health services and alcohol misuse to (1) identify those who may be at risk for postinjury arrests and (2) provide relevant resources and/or supports

Understanding implementation processes of clinical pathways and clinical practice guidelines in pediatric contexts: a study protocol

<p>Abstract</p> <p>Background</p> <p>Canada is among the most prosperous nations in the world, yet the health and wellness outcomes of Canadian children are surprisingly poor. There is some evidence to suggest that these poor health outcomes are partly due to clinical practice variation, which can stem from failure to apply the best available research evidence in clinical practice, otherwise known as knowledge translation (KT). Surprisingly, clinical practice variation, even for common acute paediatric conditions, is pervasive. Clinical practice variation results in unnecessary medical treatments, increased suffering, and increased healthcare costs. This study focuses on improving health outcomes for common paediatric acute health concerns by evaluating strategies that improve KT and reduce clinical practice variation.</p> <p>Design/Methods</p> <p>Using a multiple case study design, qualitative and quantitative data will be collected from four emergency departments in western Canada. Data sources will include: pre- and post-implementation focus group data from multidisciplinary healthcare professionals; individual interviews with the local champions, KT intervention providers, and unit/site leaders/managers; Alberta Context Tool (ACT) survey data; and aggregated patient outcome data. Qualitative and quantitative data will be systematically triangulated, and matrices will be built to do cross-case comparison. Explanations will be built about the success or lack of success of the clinical practice guidelines (CPG) and clinical pathways (CPs) uptake based upon the cross-case comparisons.</p> <p>Significance</p> <p>This study will generate new knowledge about the potential causal mechanisms and factors which shape implementation. Future studies will track the impact of the CPG/CPs implementation on children's health outcome, and healthcare costs.</p