Constructing threat probability, fear behaviour, and aversive prediction error in the brainstem.

When faced with potential threat we must estimate its probability, respond advantageously, and leverage experience to update future estimates. Threat estimates are the proposed domain of the forebrain, while behaviour is elicited by the brainstem. Yet, the brainstem is also a source of prediction error, a learning signal to acquire and update threat estimates. Neuropixels probes allowed us to record single-unit activity across a 21-region brainstem axis during probabilistic fear discrimination. Against a backdrop of widespread threat probability and behaviour signaling, a dorsally-based brainstem network rapidly signaled threat probability. Remapping of neuronal function following shock outcome gave rise to brainstem networks signaling prediction error on multiple timescales. The results reveal construction of threat probability, behaviour, and prediction error along a single brainstem axis.

Septic Shock Outcome and Factors Associated with Mortality in the Intensive Care Unit in Vietnam

Objective: To evaluate the mortality rate of septic shock patients and to learn about the associated risk factors for death. Materials and Methods: Septic shock is a life-threatening subset of sepsis with profound circulatory, cellular, and metabolic abnormalities. The authors conducted an analytical cross-sectional study on adult patients diagnosed with septic shock using Sepsis-3 criteria between May 2016 and May 2018 at an intensive care unit at a hospital in Vietnam. Data on patients’ outcomes and associated factors were collected through questionnaires and the patient medical records. To measure the association between independent variables and outcomes, odds ratio (OR) and 95% confidence interval (CI) were calculated using logistic regression. Results: One hundred fifty patients with septic shock were enrolled in the present study. Septic shock occurred in 71.3% of the 60-years-old patients and 54% were men. The mean age was 68.5±15.52 years. The mortality rate was 62% and 17.3% of patients died within 24 hours after being diagnosed with septic shock. The median length of ICU stay was four days. The initial mean SOFA and APACHE II scores were significantly higher in the death group. Septic shock patients with comorbidities had a higher mortality risk compared to those without comorbidity (OR 2.9, 95% CI 1.116 to 7.700). Patients who developed septic shock in the hospital were at greater death risk (OR 7.8, 95% CI 3.3 to 18.2). Septic shock due to pneumonia had a higher mortality risk in comparison with those due to the other causes (OR 5.2, 95% CI 2.4 to 11.0). Conclusion: The mortality rate of patients with septic shock in Vietnam was considerably high. Many factors were identified as risks, such as nosocomial infection and respiratory tract diseases. Keywords: Septic shock; Outcome; Risk factors; Vietnam

I told you it was safe: Associations between intolerance of uncertainty and different types of uncertainty during instructed threat of shock

Background and Objectives. Intolerance of Uncertainty (IU) is a dispositional tendency to find uncertainty aversive. There is a lack of research on how IU modulates physiological responding to different types of uncertainty. Methods. Here, we conducted exploratory secondary analyses on an existing data set (n = 45) to examine whether IU is related to a particular type of uncertainty during instructed threat of shock (i.e. certain shock, certain safety from shock, outcome uncertainty of shock, temporal uncertainty of shock). Results. Analyses revealed that IU was associated with larger auditory startle blink during the anticipatory period for the certain safety from shock condition, relative to the certain shock condition. Limitations. The sample was relatively small. Conclusions. Individuals higher in IU may be more inclined to generalize threat to safety cues in the context of instructed threat of shock with multiple types of uncertainty