Can computational models help elucidate the link between complex trauma and hallucinations?

Recently, a number of predictive coding models have been proposed to account for post-traumatic stress disorder (PTSD)'s symptomatology, including intrusions, flashbacks and hallucinations. These models were usually developed to account for traditional/type-1 PTSD. We here discuss whether these models also apply or can be translated to the case of complex/type-2 PTSD and childhood trauma (cPTSD). The distinction between PTSD and cPTSD is important because the disorders differ in terms of symptomatology and potential mechanisms, how they relate to developmental stages, but also in terms of illness trajectory and treatment. Models of complex trauma could give us insights on hallucinations in physiological/pathological conditions or more generally on the development of intrusive experiences across diagnostic classes.

Attentional bias toward negative stimuli in PTSD: an eye-tracking study.

BACKGROUND: Research on biased processing of aversive stimuli in posttraumatic stress disorder (PTSD) has produced inconsistent results between response time (RT) and eye-tracking studies. Recent RT-based results of dot-probe studies showed no attentional bias (AB) for threat while eye-tracking research suggested heightened sustained attention for this information. Here, we used both RT-based and eye-tracking measures to explore the dynamics of AB to negative stimuli in PTSD. METHODS: Twenty-three individuals diagnosed with PTSD, 23 trauma-exposed healthy controls, and 23 healthy controls performed an emotional dot-probe task with pairs of negative and neutral scenes presented for either 1 or 2 s. Analyses included eye movements during the presentation of the scenes and RT associated with target localization. RESULTS: There was no evidence for an AB toward negative stimuli in PTSD from RT measures. However, the main eye-tracking results revealed that all three groups showed longer dwell times on negative pictures than neutral pictures at 1 s and that this AB was stronger for individuals with PTSD. Moreover, although AB disappeared for the two groups of healthy controls with prolonged exposure, it persisted for individuals with PTSD. CONCLUSION: PTSD is associated with an AB toward negative stimuli, characterized by heightened sustained attention toward negative scenes once detected. This study sheds light on the dynamics of AB to negative stimuli in PTSD and encourages us to consider optimized therapeutic interventions targeting abnormal AB patterns.

Factors Associated With Mental Health Disorders Among University Students in France Confined During the COVID-19 Pandemic.

Importance: The coronavirus disease 2019 (COVID-19) pandemic and quarantine measures have raised concerns regarding their psychological effects on populations. Among the general population, university students appear to be particularly susceptible to experiencing mental health problems. Objectives: To measure the prevalence of self-reported mental health symptoms, to identify associated factors, and to assess care seeking among university students who experienced the COVID-19 quarantine in France. Design, Setting, and Participants: This survey study collected data from April 17 to May 4, 2020, from 69 054 students living in France during the COVID-19 quarantine. All French universities were asked to send an email to their students asking them to complete an online questionnaire. The targeted population was approximately 1 600 000 students. Exposure: Living in France during the COVID-19 quarantine. Main Outcomes and Measures: The rates of self-reported suicidal thoughts, severe distress, stress, anxiety, and depression were assessed using the 22-item Impact of Events Scale-Revised, the 10-item Perceived Stress Scale, the 20-item State-Trait Anxiety Inventory (State subscale), and the 13-item Beck Depression Inventory, respectively. Covariates were sociodemographic characteristics, precariousness indicators (ie, loss of income or poor quality housing), health-related data, information on the social environment, and media consumption. Data pertaining to care seeking were also collected. Multivariable logistic regression analyses were performed to identify risk factors. Results: A total of 69 054 students completed the survey (response rate, 4.3%). The median (interquartile range) age was 20 (18-22) years. The sample was mainly composed of women (50 251 [72.8%]) and first-year students (32 424 [47.0%]). The prevalence of suicidal thoughts, severe distress, high level of perceived stress, severe depression, and high level of anxiety were 11.4% (7891 students), 22.4% (15 463 students), 24.7% (17 093 students), 16.1% (11 133 students), and 27.5% (18 970 students), respectively, with 29 564 students (42.8%) reporting at least 1 outcome, among whom 3675 (12.4%) reported seeing a health professional. Among risk factors identified, reporting at least 1 mental health outcome was associated with female gender (odds ratio [OR], 2.10; 95% CI, 2.02-2.19; P < .001) or nonbinary gender (OR, 3.57; 95% CI, 2.99-4.27; P < .001), precariousness (loss of income: OR, 1.28; 95% CI, 1.22-1.33; P < .001; low-quality housing: OR, 2.30; 95% CI, 2.06-2.57; P < .001), history of psychiatric follow-up (OR, 3.28; 95% CI, 3.09-3.48; P < .001), symptoms compatible with COVID-19 (OR, 1.55; 95% CI, 1.49-1.61; P < .001), social isolation (weak sense of integration: OR, 3.63; 95% CI, 3.35-3.92; P < .001; low quality of social relations: OR, 2.62; 95% CI, 2.49-2.75; P < .001), and low quality of the information received (OR, 1.56; 95% CI, 1.49-1.64; P < .001). Conclusions and Relevance: The results of this survey study suggest a high prevalence of mental health issues among students who experienced quarantine, underlining the need to reinforce prevention, surveillance, and access to care.

Attentional bias towards negative stimuli in healthy individuals and the effects of trait anxiety.

This study aimed to investigate the time course of attentional bias for negative information in healthy individuals and to assess the associated influence of trait anxiety. Thirty-eight healthy volunteers performed an emotional dot-probe task with pairs of negative and neutral scenes, presented for either 1 or 2 s and followed by a target placed at the previous location of either negative or neutral stimulus. Analyses included eye movements during the presentation of the scenes and response times associated with target localization. In a second step, analyses focused on the influence of trait anxiety. While there was no significant difference at the behavioral level, the eye-tracking data revealed that negative information held longer attention than neutral stimuli once fixated. This initial maintenance bias towards negative pictures then increased with increasing trait anxiety. However, at later processing stages, only individuals with the highest trait anxiety appeared to fixate longer on negative pictures than neutral pictures, individuals with low trait anxiety showing the opposite pattern. This study provides novel evidence that healthy individuals display an attentional maintenance bias towards negative stimuli, which is associated with trait anxiety.