The cerebellum and psychological trauma: A systematic review of neuroimaging studies.

Psychological trauma is highly prevalent among psychiatric disorders, however, the relationship between trauma, neurobiology and psychopathology is not yet fully understood. The cerebellum has been recognized as a crucial structure for cognition and emotion, however, it has been relatively ignored in the literature of psychological trauma, as it is not considered as part of the traditional fear neuro-circuitry. The aim of this review is to investigate how psychological trauma affects the cerebellum and to make conclusive remarks on whether the cerebellum forms part of the trauma-affected brain circuitry. A total of 267 unique records were screened and 39 studies were included in the review. Structural cerebellar alterations and aberrant cerebellar activity and connectivity in trauma-exposed individuals were consistently reported across studies. Early-onset of adverse experiences was associated with cerebellar alterations in trauma-exposed individuals. Several studies reported alterations in connectivity between the cerebellum and nodes of large-brain networks, which are implicated in several psychiatric disorders, including the default mode network, the salience network and the central executive network. Also, trauma-exposed individuals showed altered resting state and task based cerebellar connectivity with cortical and subcortical structures that are involved in emotion and fear regulation. Our preferred interpretation of the results is through the lens of the Universal Cerebellar Transform, the hypothesis that the cerebellum, given its homogeneous cytoarchitecture, performs a common computation for motor, cognitive and emotional functions. Therefore, trauma-induced alterations in this computation might set the ground for a variety of psychiatric symptoms.

Impact of COVID-19 lockdown on individuals under treatment for substance use disorders: Risk factors for adverse mental health outcomes.

BACKGROUND: Individuals with Substance Use Disorders (SUD), are vulnerable to the psychological consequences of the COVID-19 pandemic. This is the first study to assess risk factors of adverse mental health outcomes during lockdown in a SUD population. METHODS: This was a cross-sectional study, conducted through an online survey that was completed by 303 individuals with SUD, attended in the Addiction Unit of University of Barcelona Clínic Hospital. Sociodemographic and clinical data were collected and descriptive analyses were carried out. Depending on whether individuals reported a worsening or no change/improvement in anxiety and depression symptoms during lockdown, the sample was divided in two groups. A logistic regression was then carried out to identify risk factors associated with adverse mental health outcomes. RESULTS: Overall, frequency of use for the majority of individuals with SUD remained stable during lockdown in comparison to the pre-lockdown era, although a reduction was found in frequency of tobacco, alcohol, cannabis and cocaine use in a small fraction of individuals with SUD. Symptoms of clinical anxiety were found in 58.7% of the sample while 48.2% of participants scored above the clinical threshold for depression. In addition, 50.3% of the sample reported a deterioration in depression and anxiety symptoms during lockdown that was associated with the following risk factors: previous trauma-exposure, female gender, distress and isolation, income reduction and alcohol use. CONCLUSION: A high percentage of patients with SUD experienced adverse mental health outcomes during lockdown that were associated with several risk factors, which should be taken into account in policy making and prevention strategies, as well as in clinical practice, in order to provide personalized care to SUD patients during the time of the pandemic.

The blind men and the elephant: Systematic review of systematic reviews of cannabis use related health harms.

Cannabis is the third most used psychoactive substance worldwide. The legal status of cannabis is changing in many Western countries, while we have very limited knowledge of the public health impact of cannabis-related harms. There is a need for a summary of the evidence of harms and risks attributed to cannabis use, in order to inform the definition of cannabis risky use. We have conducted a systematic review of systematic reviews, aiming to define cannabis-related harms. We included systematic reviews published until July 2018 from six different databases and following the PRISMA guidelines. To assess study quality we applied the AMSTAR 2 tool. A total of 44 systematic reviews, including 1,053 different studies, were eligible for inclusion. Harm was categorized in three dimensions: mental health, somatic harm and physical injury (including mortality). Evidence shows a clear association between cannabis use and psychosis, affective disorders, anxiety, sleep disorders, cognitive failures, respiratory adverse events, cancer, cardiovascular outcomes, and gastrointestinal disorders. Moreover, cannabis use is a risk factor for motor vehicle collision, suicidal behavior and partner and child violence. Cannabis use is a risk factor for several medical conditions and negative social consequences. There is still little data on the dose-dependency of these effects; evidence that is essential in order to define, from a public health perspective, what can be considered risky use of cannabis. This definition should be based on quantitative and qualitative criteria that informs and permits the evaluation of current approaches to a regulated cannabis market.