Subjective experiences as nodes within mental disorder networks.

What are the functional roles of subjective experiences? Answering this question amounts to charting a course for the cognitive science of consciousness, where mental processes can be described in terms of their functions. If we strategically focus on mental disorders, preliminary answers may be in sight within 25 years.

Elective Deliveries and the Risk of Autism.

INTRODUCTION: Cesarean section and induced deliveries have increased substantially in the U.S., coinciding with increases in autism spectrum disorder. Studies have documented associations between cesarean section deliveries and autism spectrum disorder but have not comprehensively accounted for medical risks. This study evaluates the extent to which cesarean section and induced deliveries are associated with autism spectrum disorder in low-risk births. METHODS: In this retrospective cohort study, California's birth records (1992-2012) were linked to hospital discharge records to identify low-risk births using a stringent algorithm based on Joint Commission guidelines. Autism spectrum disorder status was based on California Department of Developmental Service data. Logistic regression models were used to estimate associations between autism spectrum disorder and induced vaginal deliveries, cesarean section deliveries not following induction, and cesarean section deliveries following induction, with noninduced vaginal deliveries as the reference category. RESULTS: A total of 1,488,425 low-risk births took place in California from 1992 to 2012. The adjusted odds of autism spectrum disorder were 7% higher for induced vaginal deliveries (AOR=1.07, 95% CI=1.01, 1.14), 26% higher for cesarean section deliveries not following induction (AOR=1.26, 95% CI=1.19, 1.33), and 31% higher for cesarean section deliveries following induction (AOR=1.31, 95% CI=1.18, 1.45) than for noninduced vaginal deliveries. Lower gestational age and neonatal morbidities did not appear to be important underlying pathways. The associations were insensitive to alternative model specifications and across subpopulations. These results suggest that, in low-risk pregnancies, up to 10% of autism spectrum disorder cases are potentially preventable by avoiding cesarean section deliveries. CONCLUSIONS: After accounting for medical risks, elective deliveries-particularly cesarean section deliveries-were associated with a substantially increased risk of autism spectrum disorder.

Spatial Clustering of Vaccine Exemptions on the Risk of a Measles Outbreak.

OBJECTIVES: Areas of increased school-entry vaccination exemptions play a key role in epidemics of vaccine-preventable diseases in the United States. California eliminated nonmedical exemptions in 2016, which increased overall vaccine coverage but also rates of medical exemptions. We examine how spatial clustering of exemptions contributed to measles outbreak potential pre- and postpolicy change. METHODS: We modeled measles transmission in an empirically calibrated hypothetical population of youth aged 0 to 17 years in California and compared outbreak sizes under the observed spatial clustering of exemptions in schools pre- and postpolicy change with counterfactual scenarios of no postpolicy change increase in medical exemptions, no clustering of exemptions, and lower population immunization levels. RESULTS: The elimination of nonmedical exemptions significantly reduced both average and maximal outbreak sizes, although increases in medical exemptions resulted in more than twice as many infections, on average, than if medical exemptions were maintained at prepolicy change levels. Spatial clustering of nonmedical exemptions provided some initial protection against random introduction of measles infections; however, it ultimately allowed outbreaks with thousands more infections than when exemptions were randomly distributed. The large-scale outbreaks produced by exemption clusters could not be reproduced when exemptions were distributed randomly until population vaccination was lowered by >6 percentage points. CONCLUSIONS: Despite the high overall vaccinate rate, the spatial clustering of exemptions in schools was sufficient to threaten local herd immunity and reduce protection from measles outbreaks. Policies strengthening vaccine requirements may be less effective if alternative forms of exemptions (eg, medical) are concentrated in existing low-immunization areas.

The Emergence of Spatial Clustering in Medical Vaccine Exemptions Following California Senate Bill 277, 2015-2018.

Objectives. To understand how the elimination of nonmedical vaccine exemptions through California Senate Bill 277 (SB277) may have resulted in increased spatial clustering of medical exemptions.Methods. We used spatial scan statistics and negative binomial regression models to examine spatial clustering in medical vaccine exemptions in California kindergartens from 2015 to 2018.Results. Spatial clustering of medical exemptions across schools emerged following SB277. Clusters were located in similar geographic areas to previous clusters of nonmedical vaccine exemptions, suggesting a spatial association between high nonmedical exemption prevalence and increasing rates of medical exemptions. Regression results confirmed this positive association at the local level. The sociodemographic characteristics of the neighborhoods in which schools were located explained some, but not all, of the positive spatial associations between exemptions before and after SB277.Conclusions. Elimination of nonmedical vaccine exemptions via SB277 may have prompted some parents to instead seek medical exemptions to required school vaccines. The spatial association of these 2 types of exemptions has implications for maintaining pockets of low vaccine compliance and increased disease transmission.

Unconscious Psychological Treatments for Physiological Survival Circuits.

The idea of targeting unconscious or implicit processes in psychological treatments is not new, but until recently it has not been easy to manipulate these processes without also engaging consciousness. Here we review how this is possible, using various modern cognitive neuroscience methods including a technique known as Decoded Neural-Reinforcement. We discuss the general advantages of this approach, such as how it can facilitate double-blind placebo-controlled studies, and minimize premature patient dropouts in the treatment of fear. We also speculate how this may generalize to other similar physiological survival processes.

Six-fold over-representation of graduates from prestigious universities does not necessitate unmeritocratic selection in the faculty hiring process.

To achieve faculty status, graduating doctoral students have to substantially outperform their peers, given the competitive nature of the academic job market. In an ideal, meritocratic world, factors such as prestige of degree-granting university ought not to overly influence hiring decisions. However, it has recently been reported that top-ranked universities produced about 2-6 times more faculty than did universities that were ranked lower [1], which the authors claim suggests the use of un-meritocratic factors in the hiring process: how could students from top-ranked universities be six times more productive than their peers from lower-ranked universities? Here we present a signal detection model, supported by computer simulation and simple proof-of-concept example data from psychology departments in the U.S., to demonstrate that substantially higher rates of faculty production need not require substantially (and unrealistically) higher levels of student productivity. Instead, a high hiring threshold due to keen competition is sufficient to cause small differences in average student productivity between universities to result in manifold differences in placement rates. Under this framework, the previously reported results are compatible with a purely meritocratic system. Whereas these results do not necessarily mean that the actual faculty hiring market is purely meritocratic, they highlight the difficulty in empirically demonstrating that it is not so.

Anatomical coupling between distinct metacognitive systems for memory and visual perception.

A recent study found that, across individuals, gray matter volume in the frontal polar region was correlated with visual metacognition capacity (i.e., how well one's confidence ratings distinguish between correct and incorrect judgments). A question arises as to whether the putative metacognitive mechanisms in this region are also used in other metacognitive tasks involving, for example, memory. A novel psychophysical measure allowed us to assess metacognitive efficiency separately in a visual and a memory task, while taking variations in basic task performance capacity into account. We found that, across individuals, metacognitive efficiencies positively correlated between the two tasks. However, voxel-based morphometry analysis revealed distinct brain structures for the two kinds of metacognition. Replicating a previous finding, variation in visual metacognitive efficiency was correlated with volume of frontal polar regions. However, variation in memory metacognitive efficiency was correlated with volume of the precuneus. There was also a weak correlation between visual metacognitive efficiency and precuneus volume, which may account for the behavioral correlation between visual and memory metacognition (i.e., the precuneus may contain common mechanisms for both types of metacognition). However, we also found that gray matter volumes of the frontal polar and precuneus regions themselves correlated across individuals, and a formal model comparison analysis suggested that this structural covariation was sufficient to account for the behavioral correlation of metacognition in the two tasks. These results highlight the importance of the precuneus in higher-order memory processing and suggest that there may be functionally distinct metacognitive systems in the human brain.

Spatial clusters of autism births and diagnoses point to contextual drivers of increased prevalence.

Autism prevalence has risen dramatically over the past two decades in California. Although often suggested to have been crucial to the rise of autism, environmental and social contextual drivers of diagnosis have not been extensively examined. Identifying the spatial patterning of autism cases at birth and at diagnosis can help clarify which contextual drivers are affecting autism's rising prevalence. Children with autism not co-morbid with mental retardation served by the California Department of Developmental Services during the period 1992-2005 were matched to California's Birth Master Files. We search for spatial clusters of autism at time of birth and at time of diagnosis using a spatial scan approach that controls for key individual-level risk factors. We then test whether indicators of neighborhood-level diagnostic resources are associated with the diagnostic clusters and assess the extent of clustering by autism symptom severity through a multivariate scan. Finally, we test whether children who move into neighborhoods with higher levels of resources are more likely to receive an autism diagnosis relative to those who do not move with regard to resources. Significant birth and diagnostic clusters of autism are observed independent of key individual-level risk factors. While the clusters overlap, there is a strong positive association between the diagnostic clusters and neighborhood-level diagnostic resources. In addition, children with autism who are higher functioning are more likely to be diagnosed within a cluster than children with autism who are lower functioning. Most importantly, children who move into a neighborhood with more diagnostic resources than their previous residence are more likely to subsequently receive an autism diagnosis than children whose neighborhood resources do not change. We identify birth and diagnostic clusters of autism in California that are independent of individual-level autism risk factors. Our findings implicate a causal relationship between neighborhood-level diagnostic resources and spatial patterns of autism incidence but do not rule out the possibility that environmental toxicants have also contributed to autism risk.

The disappearing seasonality of autism conceptions in California.

BACKGROUND: Autism incidence and prevalence have increased dramatically in the last two decades. The autism caseload in California increased 600% between 1992 and 2006, yet there is little consensus as to the cause. Studying the seasonality of conceptions of children later diagnosed with autism may yield clues to potential etiological drivers. OBJECTIVE: To assess if the conceptions of children later diagnosed with autism cluster temporally in a systematic manner and whether any pattern of temporal clustering persists over time. METHOD: We searched for seasonality in conceptions of children later diagnosed with autism by applying a one-dimensional scan statistic with adaptive temporal windows on case and control population data from California for 1992 through 2000. We tested for potential confounding effects from known risk factors using logistic regression models. RESULTS: There is a consistent but decreasing seasonal pattern in the risk of conceiving a child later diagnosed with autism in November for the first half of the study period. Temporal clustering of autism conceptions is not an artifact of composition with respect to known risk factors for autism such as socio-economic status. CONCLUSION: There is some evidence of seasonality in the risk of conceiving a child later diagnosed with autism. Searches for environmental factors related to autism should allow for the possibility of risk factors or etiological drivers that are seasonally patterned and that appear and remain salient for a discrete number of years.

Social influence and the autism epidemic.

Despite a plethora of studies, we do not know why autism incidence has increased rapidly over the past two decades. Using California data, this study shows that children living very close to a child previously diagnosed with autism are more likely to be diagnosed with autism. An underlying social influence mechanism involving information diffusion drives this result, contributing to 16% of the increase in prevalence over 2000-2005. We eliminate competing explanations (i.e., residential sorting, environmental toxicants, and viral transmission) through seven tests and show that information diffusion simultaneously contributed to the increased prevalence, spatial clustering, and decreasing age of diagnosis.

The spatial structure of autism in California, 1993-2001.

This article identifies significant high-risk clusters of autism based on residence at birth in California for children born from 1993 to 2001. These clusters are geographically stable. Children born in a primary cluster are at four times greater risk for autism than children living in other parts of the state. This is comparable to the difference between males and females and twice the risk estimated for maternal age over 40. In every year roughly 3% of the new caseload of autism in California arises from the primary cluster we identify-a small zone 20 km by 50 km. We identify a set of secondary clusters that support the existence of the primary clusters. The identification of robust spatial clusters indicates that autism does not arise from a global treatment and indicates that important drivers of increased autism prevalence are located at the local level.

Suicide rates in the world: 1950-2004.

The cross-country differences and the trends of suicide rates in 71 countries from 1950 to 2004 are described. The data are from the World Health Organization's Mortality Database. It shows that suicide rates vary greatly across countries, even within the same region or at similar levels of development. Random-effect models were used to examine the between-country and within-country stabilities in suicide rates. The results show that more than 90% of the variance in suicide rates is due to between-country differences, suggesting suicide rates display a strong temporal stability.

Performance of the CES-D and its short forms in screening suicidality and hopelessness in the community.

A measurement scale should be short and quick to complete if it is to be practically useful. Drawing on data from a community-based survey of 2,178 people in Hong Kong, we compared five short forms (5- to 10-item) and the original version (20-item) of the Center for Epidemiologic Studies-Depression Scale (CES-D; Radloff, 1977) in predicting suicidal attempts and suicidal thoughts. Short forms with as few as nine items performed in ways very similar to the full version; a version with only five items had a detectable difference from the full version. Sensitivity, specificity, and predictive values in differentiating people with and without suicidal thought or attempt change almost linearly with the cut-offs.

Suicidal ideation and suicidal attempts in a population-based study of Chinese people: risk attributable to hopelessness, depression, and social factors.

BACKGROUND: The population attributable fraction of hopelessness, depression and other risk factors for suicidal ideation and suicidal attempts in Asian population is unknown. Social support is often said to be a buffer against the effect of hopelessness and depression. METHODS: Suicidal ideation, suicidal attempts as well as demographic and psychometric data were delineated in a random and representative population sample of 2,219 Chinese people in Hong Kong. The population attributable fraction was used to determine the contribution of hopelessness, depression and other risk factors to suicidal ideation and attempts. RESULTS: Multivariate modelling shows that about 40% of suicidal ideation and attempts was attributable to depression and about 20% was attributable to hopelessness. Drug abuse and marital dissolution were also significant contributors to suicidality. The impact of hopelessness and depression was not affected by social support. LIMITATIONS: Suicidality was self-reported. CONCLUSIONS: Suicidal ideation and suicidal attempts were to a large extent attributable to depression and hopelessness, and, to a lesser extent, drug abuse and marital dissolution. Social support appeared to play little role as a buffer.