Association between vitamin D status and eryptosis-results from the German National Cohort Study.

Vitamin D, besides its classical effect on mineral homeostasis and bone remodeling, can also modulate apoptosis. A special form of apoptosis termed eryptosis appears in erythrocytes. Eryptosis is characterized by cell shrinkage, membrane blebbing, and cell membrane phospholipid disorganization and associated with diseases such as sepsis, malaria or iron deficiency, and impaired microcirculation. To our knowledge, this is the first study that linked vitamin D with eryptosis in humans. This exploratory cross-sectional trial investigated the association between the vitamin D status assessed by the concentration of plasma 25-hydroxyvitamin D (25(OH)D) and eryptosis. Plasma 25(OH)D was analyzed by LC-MS/MS, and eryptosis was estimated from annexin V-FITC-binding erythrocytes by FACS analysis in 2074 blood samples from participants of the German National Cohort Study. We observed a weak but clear correlation between low vitamin D status and increased eryptosis (r = - 0.15; 95% CI [- 0.19, - 0.10]). There were no differences in plasma concentrations of 25(OH)D and eryptosis between male and female subjects. This finding raises questions of the importance of vitamin D status for eryptosis in terms of increased risk for anemia or cardiovascular events.

The effectiveness of cognitive behavioural therapy for social anxiety disorder in routine clinical practice.

Numerous randomized controlled trials have shown cognitive behaviour therapy (CBT) to be effective in treating social anxiety disorder (SAD). Yet, less is known about the effectiveness of CBT for SAD conducted by psychotherapists in training in routine clinical practice. In this study, 231 patients with SAD were treated with CBT under routine conditions and were examined at pre- and post-treatment as well as at 6 and 12 months follow-up. We applied self-reports to assess symptoms of SAD (defined as primary outcome), depression and psychological distress (defined as secondary outcome). We conducted both completer and intent-to-treat analyses and also assessed the reliability of change with the reliable change index. Results revealed significant reductions in symptoms of SAD between pre- and post-assessments, with effect sizes ranging from d = 0.9 to 1.2. Depending on the SAD specific questionnaire applied, 47.8% to 73.5% of the sample showed a reliable positive change, whereas 1.9% to 3.8% showed a reliable negative change. Depressive symptoms and psychological distress also decreased significantly from pre- to post-assessment, with large effect sizes. Significant treatment gains regarding both primary and secondary outcomes were further observed at 6 and 12 months follow-up. The current findings based on a large sample of patients suggest that psychotherapists in CBT training working under routine conditions can effectively treat symptoms of SAD, depression and psychological distress.

Atlas of type 2 dopamine receptors in the human brain: Age and sex dependent variability in a large PET cohort.

BACKGROUND: The dopamine system contributes to a multitude of functions ranging from reward and motivation to learning and movement control, making it a key component in goal-directed behavior. Altered dopaminergic function is observed in neurological and psychiatric conditions. Numerous factors have been proposed to influence dopamine function, but due to small sample sizes and heterogeneous data analysis methods in previous studies their specific and joint contributions remain unresolved. METHODS: In this cross-sectional register-based study we investigated how age, sex, body mass index (BMI), as well as cerebral hemisphere and regional volume influence striatal type 2 dopamine receptor (D2R) availability in the human brain. We analyzed a large historical dataset (n=156, 120 males and 36 females) of [11C]raclopride PET scans performed between 2004 and 2018. RESULTS: Striatal D2R availability decreased through age for both sexes (2-5 % in striatal ROIs per 10 years) and was higher in females versus males throughout age (7-8% in putamen). BMI and striatal D2R availability were weakly associated. There was no consistent lateralization of striatal D2R. The observed effects were independent of regional volumes. These results were validated using two different spatial normalization methods, and the age and sex effects also replicated in an independent sample (n=135). CONCLUSIONS: D2R availability is dependent on age and sex, which may contribute to the vulnerability of neurological and psychiatric conditions involving altering D2R expression.

Body dysmorphic disorder and self-esteem: a meta-analysis.

OBJECTIVE: Body dysmorphic disorder (BDD) is associated with low self-esteem. The aim of this meta-analysis was to examine the strength of the cross-sectional relationship between BDD symptom severity and global self-esteem in individuals with BDD, mentally healthy controls, community or student samples, and cosmetic surgery patients. Moreover, the role of depressive symptom severity in this relationship and other moderating factors were investigated. METHODS: A keyword-based literature search was performed to identify studies in which BDD symptoms and global self-esteem were assessed. Random effects meta-analysis of Fisher's z-transformed correlations and partial correlations controlling for the influence of depressive symptom severity was conducted. In addition to meta-analysis of the observed effects, we corrected the individual correlations for variance restrictions to address varying ranges of BDD symptom severity across samples. RESULTS: Twenty-five studies with a total of 6278 participants were included. A moderately negative relationship between BDD symptom severity and global self-esteem was found (r = -.42, CI = [-.48, -.35] for uncorrected correlations, r = -.45, CI = [-.51, -.39] for artifact-corrected correlations). A meta-analysis of partial correlations revealed that depressive symptom severity could partly account for the aforementioned relationship (pr = -.20, CI = [-.25, -.15] for uncorrected partial correlations, pr = -.23, CI = [-.28, -.17] for artifact-corrected partial correlations). The sample type (e.g., individuals with BDD, mentally healthy controls, or community samples) and diagnosis of BDD appeared to moderate the relationship only before artifact correction of effect sizes, whereas all moderators were non-significant in the meta-analysis of artifact-corrected correlations. CONCLUSIONS: The findings demonstrate that low self-esteem is an important hallmark of BDD beyond the influence of depressive symptoms. It appears that negative evaluation in BDD is not limited to appearance but also extends to other domains of the self. Altogether, our findings emphasize the importance of addressing self-esteem and corresponding core beliefs in prevention and treatment of BDD.

Low intensity technology-delivered cognitive behavioral therapy for obsessive-compulsive disorder: a meta-analysis.

BACKGROUND: Cognitive behavioral therapy (CBT) is a well-established treatment for people suffering from obsessive-compulsive disorder (OCD) and technology-based CBT applications are an emerging treatment option for people with OCD. These applications involve treatment protocols with automated content delivery and relatively low clinical contact. Whilst such CBT applications are promising, however, further investigation is needed to establish the efficacy of this treatment approach for individuals with OCD. The aim of the present study was to review the efficacy of technology-delivered CBT with minimal clinician support for OCD using a meta-analytic approach. METHODS: Randomized controlled trials (RCT) were identified through PsycINFO, Medline and Scopus resulting in 18 eligible studies (n = 1707). Control conditions comprised both passive (namely no treatment, other treatments and waitlist controls) and active. Measurement of OCD symptoms improvement was the outcome in each study. RESULTS: Participants in the technology-delivered CBT group scored lower on Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) (g = - 0.59, 95% CI = [- 0.99, - 0.18], p = 0.01), Y-BOCS and Dimensional Obsessive-Compulsive Scale (DOCS) combined (g = - 0.55, 95% CI = [- 0.87, - 0.24], p = 0.003) and Obsessive-Compulsive-Inventory-Revised (OCI-R) (g = - 0.36, 95% CI = [- 0.62, - 0.09], p = 0.02) at post-treatment than passive control groups. There were no significant findings when compared to controls with other treatments. CONCLUSIONS: This meta-analysis suggests that technology-delivered CBT with low personal contact intensity, relative to passive control groups, is an efficacious and promising treatment option for individuals with OCD. Further research is needed to allow for a comparison with control groups with other treatments.

Impaired context-sensitive adjustment of behaviour in Parkinson's disease patients tested on and off medication: An fMRI study.

The brain's sensitivity to and accentuation of unpredicted over predicted sensory signals plays a fundamental role in learning. According to recent theoretical models of the predictive coding framework, dopamine is responsible for balancing the interplay between bottom-up input and top-down predictions by controlling the precision of surprise signals that guide learning. Using functional MRI, we investigated whether patients with Parkinson's disease (PD) show impaired learning from prediction errors requiring either adaptation or stabilisation of current predictions. Moreover, we were interested in whether deficits in learning over a specific time scale would be accompanied by altered surprise responses in dopamine-related brain structures. To this end, twenty-one PD patients tested on and off dopaminergic medication and twenty-one healthy controls performed a digit prediction paradigm. During the task, violations of sequence-based predictions either signalled the need to update or to stabilise the current prediction and, thus, to react to them or ignore them, respectively. To investigate contextual adaptation to prediction errors, the probability (or its inverse, surprise) of the violations fluctuated across the experiment. When the probability of prediction errors over a specific time scale increased, healthy controls but not PD patients off medication became more flexible, i.e., error rates at violations requiring a motor response decreased in controls but increased in patients. On the neural level, this learning deficit in patients was accompanied by reduced signalling in the substantia nigra and the caudate nucleus. In contrast, differences between the groups regarding the probabilistic modulation of behaviour and neural responses were much less pronounced at prediction errors requiring only stabilisation but no adaptation. Interestingly, dopaminergic medication could neither improve learning from prediction errors nor restore the physiological, neurotypical pattern. Our findings point to a pivotal role of dysfunctions of the substantia nigra and caudate nucleus in deficits in learning from flexibility-demanding prediction errors in PD. Moreover, the data witness poor effects of dopaminergic medication on learning in PD.

Internet-based interpretation bias modification for body dissatisfaction: A three-armed randomized controlled trial.

OBJECTIVE: Appearance-related interpretation bias is postulated to play a role in the maintenance of body dissatisfaction (BD), a risk factor for body dysmorphic disorder (BDD), and eating disorders (ED). Cognitive bias modification for interpretation (CBM-I) has been shown to reduce maladaptive interpretation bias and symptoms in various emotional disorders. This study investigated the acceptability and efficacy of an easily disseminable, web-based CBM-I program for BD. METHODS: Individuals with high BD (N = 318) were randomized to a multi-session CBM-I (Sentence Word Association Paradigm [SWAP] with feedback) vs. control (SWAP without feedback) versus waitlist condition. Interpretation bias, BD and associated symptoms were assessed at baseline and post-intervention. Symptoms were monitored up to 1-week and 4-week follow-up. We further investigated transference effects to stress reactivity, as predicted by cognitive-behavioral models, at post-intervention. RESULTS: Appearance-related CBM-I led to a differential pre-post increase in adaptive interpretation patterns, particularly for appearance-related and social situations (d = 0.65-1.18). Both CBM-I and control training reduced BD, BDD symptom severity, and depression. However, CBM-I (vs. control and waitlist) improved appearance-related quality of life (d = 0.51), self-esteem (d = 0.52), and maladaptive appearance-related beliefs (d = 0.47). State stress reactivity was overall reduced in the CBM-I condition (vs. waitlist). Intervention effects largely held stable up to follow-ups. Treatment satisfaction was comparable to other CBM-I studies, with low rates of adverse reactions. DISCUSSION: These findings support assumptions of cognitive-behavioral models for BD, BDD, and ED, and suggest that web-based CBM-I is an efficacious and acceptable intervention option.

The Influence of Fitness-App Usage on Psychological Well-Being and Body Awareness-A Daily Diary Randomized Trial.

Self-tracking via fitness apps is popular and has been described as a means to enhance body awareness and well-being. However, the effects of fitness-app use and specific app functions on well-being and body awareness have yet to be targeted in controlled experimental studies. In two randomized groups, a fitness tracker was used for 6 weeks, and in one group a daily step target was implemented. In a third control group, participants documented their physical activity. A daily diary method was used to measure well-being and body trusting. In Bayesian multilevel analyses, no time, group, or interaction effects were found. These results were robust when controlling for diverse variables. It can be concluded that exercise-related self-tracking and specific step goals do not substantially influence psychological well-being and body trusting. Considering the large variability in effects, potential effects can be assumed under conditions that are to be identified in further studies.

The role of stigma during the course of inpatient psychotherapeutic treatment in a German sample.

The current study intends to investigate whether the therapeutic process is impeded by stigma and how stigma develops over the course of cognitive behavioural psychotherapy treatment. Sixty German psychotherapy inpatients were asked on a weekly basis about two facets of stigma: self-stigma and perceived public stigma. That information was linked to additional process as well as outcome variables (therapeutic engagement, working alliance, depressive, and general psychological symptoms). Both facets of stigma decreased over the course of psychotherapy, but only the decrease in self-stigma was significant. In a weekly interval, low (high) self-stigma predicted high (low) levels of working alliance and therapeutic engagement and vice versa. The current study shows that self-stigma is especially subject to change during the course of an inpatient psychotherapeutic treatment. In addition, our results point to the interrelation between self-stigma and other process variables contributing to the effectiveness and success of psychotherapy.

An integrative Bayesian approach to matrix-based analysis in neuroimaging.

Understanding the correlation structure associated with brain regions is a central goal in neuroscience, as it informs about interregional relationships and network organization. Correlation structure can be conveniently captured in a matrix that indicates the relationships among brain regions, which could involve electroencephalogram sensors, electrophysiology recordings, calcium imaging data, or functional magnetic resonance imaging (FMRI) data-We call this type of analysis matrix-based analysis, or MBA. Although different methods have been developed to summarize such matrices across subjects, including univariate general linear models (GLMs), the available modeling strategies tend to disregard the interrelationships among the regions, leading to "inefficient" statistical inference. Here, we develop a Bayesian multilevel (BML) modeling framework that simultaneously integrates the analyses of all regions, region pairs (RPs), and subjects. In this approach, the intricate relationships across regions as well as across RPs are quantitatively characterized. The adoption of the Bayesian framework allows us to achieve three goals: (a) dissolve the multiple testing issue typically associated with seeking evidence for the effect of each RP under the conventional univariate GLM; (b) make inferences on effects that would be treated as "random" under the conventional linear mixed-effects framework; and (c) estimate the effect of each brain region in a manner that indexes their relative "importance". We demonstrate the BML methodology with an FMRI dataset involving a cognitive-emotional task and compare it to the conventional GLM approach in terms of model efficiency, performance, and inferences. The associated program MBA is available as part of the AFNI suite for general use.

Between-litter variation in developmental studies of hormones and behavior: Inflated false positives and diminished power.

Developmental studies of hormones and behavior often include littermates-rodent siblings that share early-life experiences and genes. Due to between-litter variation (i.e., litter effects), the statistical assumption of independent observations is untenable. In two literatures-natural variation in maternal care and prenatal stress-entire litters are categorized based on maternal behavior or experimental condition. Here, we (1) review both literatures; (2) simulate false positive rates for commonly used statistical methods in each literature; and (3) characterize small sample performance of multilevel models (MLM) and generalized estimating equations (GEE). We found that the assumption of independence was routinely violated (>85%), false positives (α=0.05) exceeded nominal levels (up to 0.70), and power (1-ß) rarely surpassed 0.80 (even for optimistic sample and effect sizes). Additionally, we show that MLMs and GEEs have adequate performance for common research designs. We discuss implications for the extant literature, the field of behavioral neuroendocrinology, and provide recommendations.

Older fathers' children have lower evolutionary fitness across four centuries and in four populations.

Higher paternal age at offspring conception increases de novo genetic mutations. Based on evolutionary genetic theory we predicted older fathers' children, all else equal, would be less likely to survive and reproduce, i.e. have lower fitness. In sibling control studies, we find support for negative paternal age effects on offspring survival and reproductive success across four large populations with an aggregate N > 1.4 million. Three populations were pre-industrial (1670-1850) Western populations and showed negative paternal age effects on infant survival and offspring reproductive success. In twentieth-century Sweden, we found minuscule paternal age effects on survival, but found negative effects on reproductive success. Effects survived tests for key competing explanations, including maternal age and parental loss, but effects varied widely over different plausible model specifications and some competing explanations such as diminishing paternal investment and epigenetic mutations could not be tested. We can use our findings to aid in predicting the effect increasingly older parents in today's society will have on their children's survival and reproductive success. To the extent that we succeeded in isolating a mutation-driven effect of paternal age, our results can be understood to show that de novo mutations reduce offspring fitness across populations and time periods.

Data extraction and statistical errors: A quantitative critique of Gumley, Braehler, and Macbeth (2014).

OBJECTIVE: While oxytocin has been identified as having therapeutic properties for schizophrenia, the emerging evidence has been mixed which has resulted in meta-analytic reviews. We identified several errors in one such meta-analysis. Here, we highlight these errors, demonstrate the conclusions were incorrect, and state the importance of this report. METHODS: We reproduced the methods of Gumley, Braehler, and Macbeth (), including: outcomes (positive, negative, and total symptoms, as well as general psychopathology) and meta-analytic estimates for fixed and random effect models. RESULTS: Whereas Gumley, Braehler, and Macbeth () reported oxytocin had significant effects on three of four outcomes, we show that all effects were non-significant. CONCLUSIONS: Based on these null results, we hope this report encourages a re-evaluation of intranasal oxytocin as a treatment for schizophrenia.

Optimal design of the Wilcoxon-Mann-Whitney-test.

In scientific research, many hypotheses relate to the comparison of two independent groups. Usually, it is of interest to use a design (i.e., the allocation of sample sizes m and n for fixed N=m+n) that maximizes the power of the applied statistical test. It is known that the two-sample t-tests for homogeneous and heterogeneous variances may lose substantial power when variances are unequal but equally large samples are used. We demonstrate that this is not the case for the nonparametric Wilcoxon-Mann-Whitney-test, whose application in biometrical research fields is motivated by two examples from cancer research. We prove the optimality of the design m=n in case of symmetric and identically shaped distributions using normal approximations and show that this design generally offers power only negligibly lower than the optimal design for a wide range of distributions.

Testing for publication bias in diagnostic meta-analysis: a simulation study.

The present study investigates the performance of several statistical tests to detect publication bias in diagnostic meta-analysis by means of simulation. While bivariate models should be used to pool data from primary studies in diagnostic meta-analysis, univariate measures of diagnostic accuracy are preferable for the purpose of detecting publication bias. In contrast to earlier research, which focused solely on the diagnostic odds ratio or its logarithm ( ln ω), the tests are combined with four different univariate measures of diagnostic accuracy. For each combination of test and univariate measure, both type I error rate and statistical power are examined under diverse conditions. The results indicate that tests based on linear regression or rank correlation cannot be recommended in diagnostic meta-analysis, because type I error rates are either inflated or power is too low, irrespective of the applied univariate measure. In contrast, the combination of trim and fill and ln ω has non-inflated or only slightly inflated type I error rates and medium to high power, even under extreme circumstances (at least when the number of studies per meta-analysis is large enough). Therefore, we recommend the application of trim and fill combined with ln ω to detect funnel plot asymmetry in diagnostic meta-analysis.

A deep learning method for comparing Bayesian hierarchical models.

Bayesian model comparison (BMC) offers a principled approach to assessing the relative merits of competing computational models and propagating uncertainty into model selection decisions. However, BMC is often intractable for the popular class of hierarchical models due to their high-dimensional nested parameter structure. To address this intractability, we propose a deep learning method for performing BMC on any set of hierarchical models which can be instantiated as probabilistic programs. Since our method enables amortized inference, it allows efficient re-estimation of posterior model probabilities and fast performance validation prior to any real-data application. In a series of extensive validation studies, we benchmark the performance of our method against the state-of-the-art bridge sampling method and demonstrate excellent amortized inference across all BMC settings. We then showcase our method by comparing four hierarchical evidence accumulation models that have previously been deemed intractable for BMC due to partly implicit likelihoods. Additionally, we demonstrate how transfer learning can be leveraged to enhance training efficiency. We provide reproducible code for all analyses and an open-source implementation of our method. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Computerized cognitive control training to reduce rumination in major depression: A randomized controlled trial.

OBJECTIVE: Rumination is a major risk factor for the onset and recurrence of depressive episodes and has been associated with deficits in updating working memory content. This randomized controlled trial examines whether training updating-specific cognitive control processes reduces daily ruminative thoughts in clinically depressed individuals. METHODS: Sixty-five individuals with a current major depressive episode were randomized to 10 sessions of either cognitive control training (N = 31) or placebo training (N = 34). The frequency and negativity of individuals' daily ruminative thoughts were assessed for seven days before training, after training, and at a 3-month follow-up using experience sampling methodology. Secondary outcomes were depressive symptoms, depressed mood, and level of disability. RESULTS: Cognitive control training led to stronger improvements in the trained task than placebo training. However, cognitive control training did not lead to greater reductions in the frequency or negativity of daily ruminative thoughts than placebo training. There were no training-specific effects on participants' depressive symptoms or level of disability. CONCLUSIONS: The robustness of the present null-findings, combined with the methodological strengths of the study, suggest that training currently depressed individuals to update emotional content in working memory does not affect the frequency or negativity of their daily ruminative thoughts.

Methylphenidate and Short-Term Cardiovascular Risk.

Importance: There are concerns about the safety of medications for treatment of attention-deficit/hyperactivity disorder (ADHD), with mixed evidence on possible cardiovascular risk. Objective: To assess whether short-term methylphenidate use is associated with risk of cardiovascular events. Design, Setting, and Participants: This retrospective, population-based cohort study was based on national Swedish registry data. Participants were individuals with ADHD aged 12 to 60 years with dispensed prescriptions of methylphenidate between January 1, 2007, and June 30, 2012. Each person receiving methylphenidate (n = 26 710) was matched on birth date, sex, and county to up to 10 nonusers without ADHD (n = 225 672). Statistical analyses were performed from September 13, 2022, to May 16, 2023. Main Outcomes and Measures: Rates of cardiovascular events, including ischemic heart disease, venous thromboembolism, heart failure, or tachyarrhythmias, 1 year before methylphenidate treatment and 6 months after treatment initiation were compared between individuals receiving methylphenidate and matched controls using a bayesian within-individual design. Analyses were stratified by history of cardiovascular events. Results: The cohort included 252 382 individuals (15 442 [57.8% men]; median age, 20 (IQR, 15-31) years). The overall incidence of cardiovascular events was 1.51 per 10 000 person-weeks (95% highest density interval [HDI], 1.35-1.69) for individuals receiving methylphenidate and 0.77 (95% HDI, 0.73-0.82) for the matched controls. Individuals treated with methylphenidate had an 87% posterior probability of having a higher rate of cardiovascular events after treatment initiation (incidence rate ratio [IRR], 1.41; 95% HDI, 1.09-1.88) compared with matched controls (IRR, 1.18; 95% HDI, 1.02-1.37). The posterior probabilities were 70% for at least a 10% increased risk of cardiovascular events in individuals receiving methylphenidate vs 49% in matched controls. No difference was found in this risk between individuals with and without a history of cardiovascular disease (IRR, 1.11; 95% HDI, 0.58-2.13). Conclusions and Relevance: In this cohort study, individuals receiving methylphenidate had a small increased cardiovascular risk vs matched controls in the 6 months after treatment initiation. However, there was little evidence for an increased risk of 20% or higher and for differences in risk increase between people with and without a history of cardiovascular disease. Therefore, before treatment initiation, careful consideration of the risk-benefit trade-off of methylphenidate would be useful, regardless of cardiovascular history.

Smoking is associated with increased eryptosis, suicidal erythrocyte death, in a large population-based cohort.

Smoking has multiple detrimental effects on health, and is a major preventable cause of premature death and chronic disease. Despite the well-described effect of inhaled substances from tobacco smoke on cell toxicity, the association between smoking and suicidal erythrocyte death, termed eryptosis, is virtually unknown. Therefore, the blood samples of 2023 participants of the German National Cohort Study (NAKO) were analyzed using flow cytometry analysis to determine eryptosis from fluorescent annexin V-FITC-binding to phosphatidylserine-exposing erythrocytes. Blood analyses were complemented by the measurement of hematologic parameters including red blood cell count, hematocrit, hemoglobin, mean corpuscular cell volume (MCV) and mean corpuscular hemoglobin (MCH). Eryptosis was higher in smokers than in non- and ex-smokers, and positively associated with the number of cigarettes smoked daily (r = 0.08, 95% CI [0.03, 0.12]). Interestingly, despite increased eryptosis, smokers had higher red blood cell indices than non-smokers. To conclude, smokers were characterized by higher eryptosis than non-smokers, without showing any obvious detrimental effect on classic hematological parameters.

Social and environmental transmission spread different sets of gut microbes in wild mice.

Gut microbes shape many aspects of organismal biology, yet how these key bacteria transmit among hosts in natural populations remains poorly understood. Recent work in mammals has emphasized either transmission through social contacts or indirect transmission through environmental contact, but the relative importance of different routes has not been directly assessed. Here we used a novel radio-frequency identification-based tracking system to collect long-term high-resolution data on social relationships, space use and microhabitat in a wild population of mice (Apodemus sylvaticus), while regularly characterizing their gut microbiota with 16S ribosomal RNA profiling. Through probabilistic modelling of the resulting data, we identify positive and statistically distinct signals of social and environmental transmission, captured by social networks and overlap in home ranges, respectively. Strikingly, microorganisms with distinct biological attributes drove these different transmission signals. While the social network effect on microbiota was driven by anaerobic bacteria, the effect of shared space was most influenced by aerotolerant spore-forming bacteria. These findings support the prediction that social contact is important for the transfer of microorganisms with low oxygen tolerance, while those that can tolerate oxygen or form spores may be able to transmit indirectly through the environment. Overall, these results suggest social and environmental transmission routes can spread biologically distinct members of the mammalian gut microbiota.