The development of psychotic disorders in adolescence: a potential role for hormones

The Impact of Exposure to Iodine and Fluorine in Drinking Water on Thyroid Health and Intelligence in School-Age Children: A Cross-Sectional Investigation

Iodine and fluorine, as halogen elements, are often coexisting in water environments, with nearly 200 million people suffering from fluorosis globally, and, in 11 countries and territories, adolescents have iodine intakes higher than that required for the prevention of iodine deficiency disorders. It has been suggested that excess iodine and/or fluorine can affect thyroid health and intellectual development, especially in children, but their combined effect has been less studied in this population. This study investigated 399 school-age children in Tianjin, China, collected drinking water samples from areas where the school-age children lived, and grouped the respondents according to iodine and fluorine levels. Thyroid health was measured using thyroid hormone levels, thyroid volume, and the presence of thyroid nodules; intelligence quotient (IQ) was assessed using the Raven's Progressive Matrices (CRT) test; and monoamine neurotransmitter levels were used to explore the potential relationship between thyroid health and intelligence. Multiple linear regression and restricted cubic spline (RCS) analyses showed that iodine and fluorine were positively correlated with thyroid volume and the incidence of thyroid nodules in school-age children, and negatively correlated with IQ; similar results were obtained in the secondary subgroups based on urinary iodine and urinary fluoride levels. Interaction analyses revealed a synergistic effect of iodine and fluorine. A pathway analysis showed that iodine and fluorine were negatively associated with the secretion of free triiodothyronine (FT3) and free tetraiodothyronine (FT4), which in turn were negatively associated with the secretion of thyroid-stimulating hormone (TSH). Iodine and fluorine may affect IQ in school-aged children through the above pathways that affect thyroid hormone secretion; of these, FT3 and TSH were negatively correlated with IQ, whereas FT4 was positively correlated with IQ. The relationship between thyroid hormones and monoamine neurotransmitters may involve the hypothalamic-pituitary-thyroid axis, with FT4 hormone concentrations positively correlating with dopamine (DA), norepinephrine (NE), and 5-hydroxytryptophan (5-HT) concentrations, and FT3 hormone concentrations positively correlating with DA concentrations. Monoamine neurotransmitters may play a mediating role in the effects of iodine and fluoride on intelligence in schoolchildren. However, this study has some limitations, as the data were derived from a cross-sectional study in Tianjin, China, and no attention was paid to the reciprocal effects of iodine and fluorine at different doses on thyroid health and intelligence in schoolchildren in other regions.

The Critical Roles of Early Development, Stress, and Environment in the Course of Psychosis

Psychotic disorders are highly debilitating with poor prognoses and courses of chronic illness. In recent decades, conceptual models have shaped understanding, informed treatment, and guided research questions. However, these models have classically focused on the adolescent and early adulthood stages immediately preceding onset while conceptualizing early infancy through all of childhood as a unitary premorbid period. In addition, models have paid limited attention to differential effects of types of stress; contextual factors such as local, regional, and country-level characteristics or sociocultural contexts; and the timing of the stressor or environmental risk. This review discusses emerging research suggesting that (a) considering effects specific to neurodevelopmental stages prior to adolescence is highly informative, (b) understanding specific stressors and levels of environmental exposures (i.e., systemic or contextual features) is necessary, and (c) exploring the dynamic interplay between development, levels and types of stressors, and environments can shed new light, informing a specified neurodevelopmental and multifaceted diathesis-stress model.

Cognitive Dysfunction as a Risk Factor for Psychosis

The current chapter summarizes recent evidence for cognition as a risk factor for the development of psychosis, including the range of cognitive impairments that exist across the spectrum of psychosis risk symptoms. The chapter examines several possible theories linking cognitive deficits with the development of psychotic symptoms, including evidence that cognitive deficits may be an intermediate risk factor linking genetic and/or neural metrics to psychosis spectrum symptoms. Although there is not strong evidence for unique cognitive markers associated specifically with psychosis compared to other forms of psychopathology, psychotic disorders are generally associated with the greatest severity of cognitive deficits. Cognitive deficits precede the development of psychotic symptoms and may be detectable as early as childhood. Across the psychosis spectrum, both the presence and severity of psychotic symptoms are associated with mild to moderate impairments across cognitive domains, perhaps most consistently for language, cognitive control, and working memory domains. Research generally indicates the size of these cognitive impairments worsens as psychosis symptom severity increases. The chapter points out areas of unclarity and unanswered questions in each of these areas, including regarding the mechanisms contributing to the association between cognition and psychosis, the timing of deficits, and whether any cognitive systems can be identified that function as specific predictors of psychosis risk symptoms.

Development of Thalamocortical Structural Connectivity in Typically Developing and Psychosis Spectrum Youths

BACKGROUND

Thalamocortical white matter connectivity is disrupted in psychosis and is hypothesized to play a role in its etiology and associated cognitive impairment. Attenuated cognitive symptoms often begin in adolescence, during a critical phase of white matter and cognitive development. However, little is known about the development of thalamocortical white matter connectivity and its association with cognition.

METHODS

This study characterized effects of age, sex, psychosis symptomatology, and cognition in thalamocortical networks in a large sample of youths (N = 1144, ages 8-22 years, 46% male) from the Philadelphia Neurodevelopmental Cohort, which included 316 typically developing youths, 330 youths on the psychosis spectrum, and 498 youths with other psychopathology. Probabilistic tractography was used to quantify percent total connectivity between the thalamus and six cortical regions and assess microstructural properties (i.e., fractional anisotropy) of thalamocortical white matter tracts.

RESULTS

Overall, percent total connectivity of the thalamus was weakly associated with age and was not associated with psychopathology or cognition. In contrast, fractional anisotropy of all thalamocortical tracts increased significantly with age, was generally higher in males than females, and was lowest in youths on the psychosis spectrum. Fractional anisotropy of tracts linking the thalamus to prefrontal and posterior parietal cortices was related to better cognitive function across subjects.

CONCLUSIONS

By characterizing the pattern of typical development and alterations in those at risk for psychotic disorders, this study provides a foundation for further conceptualization of thalamocortical white matter microstructure as a marker of neurodevelopment supporting cognition and an important risk marker for psychosis.

Peripheral biomarkers to predict the diagnosis of bipolar disorder from major depressive disorder in adolescents

The onset of bipolar disorder (BD) occurs in childhood or adolescence in half of the patients. Early stages of BD usually present depressive episodes, which makes it difficult to be distinguished from major depressive disorder (MDD). Objective biomarkers for discriminating BD from MDD in adolescent patients are limited. We collected basic demographic data and the information of the first blood examination performed after the admission to psychiatry unit of BD and MDD inpatients during 2009-2018. We recruited 261 adolescents (aged from 10 to 18), including 160 MDD and 101 BD. Forward-Stepwise Selection of binary logistic regression was used to construct predictive models for the total sample and subgroups by gender. Independent external validation was made by 255 matched patients from another hospital in China. Regression models of total adolescents, male and female subgroups showed accuracy of 73.3%, 70.6% and 75.2%, with area under curves (AUC) as 0.785, 0.816 and 0.793, respectively. Age, direct bilirubin (DBIL), lactic dehydrogenase (LDH), free triiodothyronine (FT3) and C-reactive protein (CRP) were final factors included into the models. The discrimination was well at external validation (AUC = 0.714). This study offers the evidence that accessible information of common clinical laboratory examination might be valuable in distinguishing BD form MDD in adolescents. With good diagnostic accuracies and external validation, the total regression equation might potentially be applied to individualized clinical inferences on adolescent BD patients.

Differential effects of chronic adolescent glucocorticoid or methamphetamine on drug-induced locomotor hyperactivity and disruption of prepulse inhibition in adulthood in mice

Sensitization of dopaminergic activity has been suggested as an underlying mechanism in the psychotic symptoms of schizophrenia. Adolescent stress and chronic abuse of methamphetamine (Meth) are well-known risk factors for psychosis and schizophrenia; however it remains unknown how these factors compare in terms of dopaminergic behavioural sensitization in adulthood. In addition, while Brain-Derived Neurotrophic Factor (BDNF) has been implicated in dopaminergic activity and schizophrenia, its role in behavioural sensitization remains unclear. In this study we therefore compared the effect of chronic adolescent treatment with the stress hormone, corticosterone (Cort), or with Meth, on drug-induced locomotor hyperactivity and disruption of prepulse inhibition in adulthood in BDNF heterozygous mice and their wild-type controls, as well as on dopamine receptor gene expression. Between 6 and 9 weeks of age, the animals either received Cort in the drinking water or were treated with an escalating Meth dose protocol. In adulthood, Cort-pretreated mice showed significantly reduced Meth-induced locomotor hyperactivity compared to vehicle-pretreated mice. In contrast, Meth hyperlocomotion was significantly enhanced in animals pretreated with the drug in adolescence. There were no effects of either pretreatment on prepulse inhibition. BDNF Het mice showed greater Meth-induced hyperlocomotion and lower prepulse inhibition than WT mice. There were no effects of either pretreatment on D1 or D2 gene expression in either the dorsal or ventral striatum, while D3 mRNA was shown to be reduced in male mice only irrespective of genotype. These results suggest that in adolescence, chronically elevated glucocorticoid levels, a component of chronic stress, do not cause dopaminergic sensitization adulthood, in contrast to the effect of chronic Meth treatment in the same age period. BDNF does not appear to be involved in the effects of chronic Cort or chronic Meth.

Equity in Mental Health Services for Youth at Clinical High Risk for Psychosis: Considering Marginalized Identities and Stressors

Prevention and early intervention programs have been initiated worldwide to serve youth at Clinical High Risk for Psychosis (CHR-P), who are adolescents and young adults experiencing subclinical psychosis and functional impairment. The primary goals of these efforts are to prevent or mitigate the onset of clinical psychosis, while also treating comorbid issues. It is important to consider issues of diversity, equity, and inclusion in CHR-P work, especially as these programs continue to proliferate around the world. Further, there is a long history in psychiatry of misdiagnosing and mistreating psychosis in individuals from racial and ethnic minority groups. Although there have been significant developments in early intervention psychosis work, there is evidence that marginalized groups are underserved by current CHR-P screening and intervention efforts. These issues are compounded by the contexts of continued social marginalization and significant mental health disparities in general child/adolescent services. Within this narrative review and call to action, we use an intersectional and minority stress lens to review and discuss current issues related to equity in CHR-P services, offer evidence-based recommendations, and propose next steps. In particular, our intersectional and minority stress lenses incorporate perspectives for a range of marginalized and underserved identities related to race, ethnicity, and culture; faith; immigration status; geography/residence; gender identity; sexual orientation; socioeconomic status/class; and ability status.

Systematic discovery of signaling pathways linking immune activation to schizophrenia

Immune activation has been shown to play a critical role in the development of schizophrenia; however its underlying mechanism remains unknown. Our report demonstrates a high-quality protein interaction network for schizophrenia (SCZ Network), constructed using our “neighborhood walk” approach in combination with “random walk with restart”. The spatiotemporal expression pattern of the genes in this disease network revealed two developmental stages sensitive to perturbation by immune activation: mid-to late gestation, and adolescence. Furthermore, we induced immune activation at these stages in mice, carried out transcriptome sequencing on the mouse brains, and illustrated clear potential molecular pathways and key regulators correlating maternal immune activation during gestation and an increased risk for schizophrenia after a second immune activation at puberty. This work provides not only valuable resources for the study on molecular mechanisms underlying schizophrenia, but also a systematic strategy for the discovery of molecular pathways of complex mental disorders.

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A high-quality molecular network for schizophrenia (SCZ Network)

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A landscape of molecular pathways linking immune activation and schizophrenia

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The spatiotemporal network dynamics revealing stages susceptible to immune activation

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Identification of the molecular pathways and regulators in the immune-activated brain

Adolescent Neurodevelopment and Vulnerability to Psychosis

Adolescence is characterized by significant changes in several domains, including brain structure and function, puberty, and social and environmental factors. Some of these changes serve to increase the likelihood of psychosis onset during this period, while others may buffer this risk. This review characterizes our current knowledge regarding the unique aspects of adolescence that may serve as risk factors for schizophrenia spectrum disorders. In addition, we provide potential future directions for research into adolescent-specific developmental mechanisms that impart vulnerability to psychosis and the possibility of interventions that capitalize on adolescents' unique characteristics. Specifically, we explore the ways in which gray and white matter develop throughout adolescence in typically developing youth as well as in those with psychosis spectrum disorders. We also discuss current views on the function that social support and demands, as well as role expectations, play in risk for psychosis. We further highlight the importance of considering biological factors such as puberty and hormonal changes as areas of unique vulnerability for adolescents. Finally, we discuss cannabis use as a factor that may have a unique impact during adolescent neurodevelopment, and subsequently potentially impact psychosis onset. Throughout, we include discussion of resilience factors that may provide unique opportunities for intervention during this dynamic life stage.

The Brain Emotional Systems in Addictions: From Attachment to Dominance/Submission Systems

Human development has become particularly complex during the evolution. In this complexity, adolescence is an extremely important developmental stage. Adolescence is characterized by biological and social changes that create the prerequisites to psychopathological problems, including both substance and non-substance addictive behaviors. Central to the dynamics of the biological changes during adolescence are the synergy between sexual and neurophysiological development, which activates the motivational/emotional systems of Dominance/Submission. The latter are characterized by the interaction between the sexual hormones, the dopaminergic system and the stress axis (HPA). The maturation of these motivational/emotional systems requires the integration with the phylogenetically more recent Attachment/CARE Systems, which primarily have governed the subject's relationships until puberty. The integration of these systems is particularly complex in the human species, due to the evolution of the process of competition related to sexual selection: from a simple fight between two individuals (of the same genus and species) to a struggle for the acquisition of a position in rank and the competition between groups. The latter is an important evolutionary acquisition and believed to be the variable that has most contributed to enhancing the capacity for cooperation in the human species. The interaction between competition and cooperation, and between competition and attachment, characterizes the entire human relational and emotional structure and the unending work of integration to which the BrainMind is involved. The beginning of the integration of the aforementioned motivational/emotional systems is currently identified in the prepubertal period, during the juvenile stage, with the development of the Adrenarche-the so-called Adrenal Puberty. This latter stage is characterized by a low rate of release of androgens, the hormones released by the adrenal cortex, which activate the same behaviors as those observed in the PLAY system. The Adrenarche and the PLAY system are biological and functional prerequisites of adolescence, a period devoted to learning the difficult task of integrating the phylogenetically ancient Dominance/Submission Systems with the newer Attachment/CARE Systems. These systems accompany very different adaptive goals which can easily give rise to mutual conflict and can in turn make the balance of the BrainMind precarious and vulnerable to mental suffering.

Attenuated Psychotic Symptoms in Adolescents With Chronic Cannabis and MDMA Use

OBJECTIVES

Both substance use, on the one hand, and the first signs of psychosis, on the other, commonly begin in adolescence. Adolescents with substance use disorder (SUD) frequently show recreational use of cannabis and 3,4-methylenedioxymethamphetamine (MDMA). When attenuated psychotic symptoms (APS) occur during the course of SUD, they are commonly attributed to the cannabis use, neglecting the role of other substances abused, such as MDMA in the risk of psychosis.

METHODS

We analyzed retrospective self-reports on APS (Prodromal Questionnaire, PQ-16) and amount of cannabis and MDMA use in n = 46 adolescent psychiatry outpatients with SUD. N = 17 (35%) individuals reported MDMA consume additional to cannabis. Furthermore, we examined the associations of APS with cannabis and MDMA use in stepwise hierarchical regressions while controlling for trauma history, birth complications and gender.

RESULTS

APS were not related to cannabis (B = 0.04, p = 0.842), but to MDMA use (B = 4.88, p = 0.001) and trauma history (B = 0.72, p = 0.001). Gender (B = -0.22, p = 0.767) and birth complications (B = -0.68, p = 0.178) were not associated with APS.

DISCUSSION

Our results indicate that MDMA use additional to cannabis use is associated with APS among adolescent SUD patients. Contrary to our expectations, we did not see an association of cannabis use and APS. We speculate that cannabis increases the risk for psychosis after a longer period of use and in combination with other risk factors, such as trauma history. Clinicians should screen for APS among SUD patients using MDMA and cannabis in order to adapt treatment plans of SUDs. Future research should validate these findings in longitudinal studies including polysubstance use and trauma history.

Glucose Metabolism, Thyroid Function, and Prolactin Level in Adolescent Patients With First Episode of Schizophrenia and Affective Disorders

Schizophrenia and affective spectrum disorders (ASD) typically begin in adolescence or early adulthood. The pathophysiological mechanisms underlying these disorders are still not fully understood, and recent studies have suggested an involvement of dysfunctions in cardiometabolic and neuroendocrine systems at the onset of both disorders. In this context, we aimed to assess thyroid function, prolactin level, glucose metabolism, and lipid profile in drug naive adolescents, comparing patients with first episode of schizophrenia spectrum disorders (SSD) and patients with ASD. We performed a retrospective chart review from inpatients aged from ten to eighteen years, referred to Child and Adolescent Psychiatric Unit of University of Bari "Aldo Moro" over a period of 4 years, with diagnosis of SSD (n=30) or ASD (n=22), according to Diagnostic and Statistical Manual for Mental Disorders-fifth edition (DSM-5) criteria. Data on serum prolactin, glucose, insulin, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, thyroid stimulating hormone, free triiodothyronin, and free thyroxin were collected, and the insulin resistance (IR) indexes "HOMA1-IR" and "HOMA2-IR" were calculated. The multivariable linear regression models, adjusting for potential confounding factors (age, sex, and BMI), showed HOMA1-IR (p=0.001), HOMA2-IR (p=0.002), glucose (p=0.004), insulin (p=0.004) and free thyroxin (p<0.001) values higher in the SSD group than in ASD. No others significant differences were found. Our findings suggest the need for a metabolic and endocrine screening at the onset of SSD and ASD, particularly for indexes of IR, that is a testable and treatable risk factor for cardiometabolic diseases. Further studies are required to better understand the role of endocrinological and metabolic dysfunctions at the onset of severe mental illness also considering influencing factors as age, gender, and BMI.

Timing of menarche and abnormal hippocampal connectivity in youth at clinical-high risk for psychosis

The "estrogen hypothesis" suggests that estrogen is a protective factor against psychotic disorders such as schizophrenia. Although the precise protective mechanisms are still unclear, one potential explanation lies in the role that increased estrogens play in mediating hippocampal plasticity, as this may reduce hippocampal dysconnectivity that is characteristically observed in psychosis. In support of this view, later age at menarche- less available estrogen during critical early adolescent development- is related to earlier onset of psychosis and increased symptom severity. Furthermore, if estrogens have protective effects, then we should see this effect in the psychosis risk period in those at clinical high-risk (CHR) for psychosis - i.e., individuals showing attenuated symptoms at imminent risk for transitioning to a psychotic diagnosis. This study examined whether earlier age at menarche would result in more normative hippocampal connectivity in CHR youth; menarche is an easily assessed, developmental marker associated with the availability of estrogens. Resting-state connectivity was examined in sixty female participants (26 CHR and 34 healthy control; age 12-21) using a cross-sectional approach; hippocampal connectivity was found to relate to age at menarche. Later age at menarche in the CHR group related to increased hippocampal dysconnectivity to the occipital cortex (a region with a neurotrophic response to estrogen) compared to the controls. Results suggest that earlier availability of estrogens may have neuroprotective effects on hippocampal plasticity. Findings have relevance for understanding sex differences and etiology, as well as guiding novel treatments.

Sex hormone levels in drug-naïve, first-episode patients with psychosis

Aim: Sex differences have long been reported in schizophrenia leading to the hypothesis that sex hormones may be implicated in the pathophysiology of the disorder. We assessed gonadal hormones during the fasted state in drug-naïve patients with psychosis.Method: Fasting serum concentrations of follicular-stimulating hormone (FSH) and luteinizing hormone (LH), testosterone, free-testosterone, Sex Hormone Binding Globulin (SHBG) and oestradiol (E₂) were compared between a group of 55 newly diagnosed, drug-naïve, first-episode men with psychosis and a group of 55 healthy controls, matched for age, smoking status and BMI. Testosterone, free-testosterone and SHBG were compared between a group of 32 drug-naïve, first-episode females with psychosis and a group of 32 healthy controls matched for age, smoking status and BMI.Results: Testosterone and free-testosterone levels were significantly lower in the patients' group and SHBG levels significantly higher in the patients' group compared to those in healthy controls. The two female groups had similar values in the hormones which were measured.Conclusion: Our findings provide evidence of lower testosterone and free-testosterone levels and increased SHBG levels in drug-naïve, first-episode males with psychosis.KEY POINTSReduced testosterone and free-testosterone levels in drug-naive, first-episode males with psychosis.Increased SHBG levels in drug-naive first-episode males with psychosis.No difference in FSH, LH and E2 levels between drug-naive first episode males with psychosis and controls.No difference in testosterone, free-testosterone and SHBG levels between drug-naive, first-episode women with psychosis and controls.

Social Behavior: Developmental Timing Defies Puberty

A closer look at behavioral development in seasonally breeding rodents reveals more complex relations between puberty and social behavior than previously recognized. Pubertal hormones determine gross amounts of behavior, but play recedes and aggression emerges independently of puberty at predetermined chronological ages.

Insulin Resistance in Schizophrenia

Schizophrenia and diabetes have been known to be linked disorders for decades. One reason is due to the fact that a major side effect of antipsychotic medication treatment is metabolic syndrome, which increases the risk of the patients developing type 2 diabetes and cardiovascular disorders. However, signs of metabolic syndrome in schizophrenia patients were identified more than 100 years ago, even before the development of antipsychotic drugs. This suggests that schizophrenia itself predisposes towards diabetes and, in turn, insulin resistance may be a risk factor for the development of schizophrenia. This review summarizes the findings surrounding this issue and places them into context with regards to increasing our understanding of the aetiology of schizophrenia and in support of biomarker and drug discovery efforts.

Adult report of childhood imaginary companions and adversity relates to concurrent prodromal psychosis symptoms

Hallucination and dissociation have been found to be associated with imaginary friend play in childhood (CIC). Past studies have not investigated how this play relates to adult prodromal symptoms or how childhood adversity mediates the relationship. CIC play was examined in 278 participants, 18-24 years. CIC status predicted prodromal symptoms of hallucination only, whereas childhood adversity predicted all other symptoms. Mediation analysis found CIC's relation to hallucination symptoms was partially mediated by childhood adversity. Findings fit with views that CIC are a positive childhood experience which may convert to a negative developmental trajectory through the impact of childhood adversity.

Disruptions in White Matter Maturation and Mediation of Cognitive Development in Youths on the Psychosis Spectrum

BACKGROUND

Psychosis onset typically occurs in adolescence, and subclinical psychotic experiences peak in adolescence. Adolescence is also a time of critical neural and cognitive maturation. Using cross-sectional data from the Philadelphia Neurodevelopmental Cohort, we examined whether regional white matter (WM) development is disrupted in youths with psychosis spectrum (PS) features and whether WM maturation mediates the relationship between age and cognition in typically developing (TD) youths and youths with PS features.

METHODS

We examined WM microstructure, as assessed via diffusion tensor imaging, in 670 individuals (age 10-22 years; 499 TD group, 171 PS group) by using tract-based spatial statistics. Multiple regressions were used to evaluate age × group interactions on regional WM indices. Mediation analyses were conducted on four cognitive domains-executive control, complex cognition, episodic memory, and social cognition-using a bootstrapping approach.

RESULTS

There were age × group interactions on fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF) and retrolenticular internal capsule. Follow-up analyses revealed these effects were significant in both hemispheres. Bilateral SLF FA mediated the relationship between age and complex cognition in the TD group, but not the PS group. Regional FA did not mediate the age-associated increase in any of the other cognitive domains.

CONCLUSIONS

Our results showed aberrant age-related effects in SLF and retrolenticular internal capsule FA in youths with PS features. SLF development supports emergence of specific higher-order cognitive functions in TD youths, but not in youths with PS features. Future mechanistic explanations for these relationships could facilitate development of earlier and refined targets for therapeutic interventions.

The 'honeymoon effect' and 'gate fever' in a secure forensic adolescent psychiatric hospital: Do they exist?

There is limited research that comments on whether there are recurring patterns for incidents or significant events during inpatient admissions to psychiatric units. This is even more so the case for an adolescent population. This study looked at 30 consecutive female patient admissions to Bluebird House, a medium secure adolescent unit in the South of England, to identify whether both the 'honeymoon effect' (low incident rate in the first 28 days following admission) and 'gate fever' (high incident rate in the last 28 days prior to discharge) were identifiable phenomena. Analysis of the incident rate found that in our secure adolescent population, the number of incidents both in the first week and at the first 28 days was higher in comparison to the whole admission. We also did not find a consistent increase in incidents in the final 28 days of the admission.

Prenatal immune activation alters the adult neural epigenome but can be partly stabilised by a n-3 polyunsaturated fatty acid diet

An unstable epigenome is implicated in the pathophysiology of neurodevelopmental disorders such as schizophrenia and autism. This is important because the epigenome is potentially modifiable. We have previously reported that adult offspring exposed to maternal immune activation (MIA) prenatally have significant global DNA hypomethylation in the hypothalamus. However, what genes had altered methylation state, their functional effects on gene expression and whether these changes can be moderated, have not been addressed. In this study, we used next-generation sequencing (NGS) for methylome profiling in a MIA rodent model of neurodevelopmental disorders. We assessed whether differentially methylated regions (DMRs) affected the chromatin state by mapping known DNase I hypersensitivity sites (DHSs), and selected overlapping genes to confirm a functional effect of MIA on gene expression using qPCR. Finally, we tested whether methylation differences elicited by MIA could be limited by post-natal dietary (omega) n-3 polyunsaturated fatty acid (PUFA) supplementation. These experiments were conducted using hypothalamic brain tissue from 12-week-old offspring of mice injected with viral analogue PolyI:C on gestation day 9 of pregnancy or saline on gestation day 9. Half of the animals from each group were fed a diet enriched with n-3 PUFA from weaning (MIA group, n = 12 units, n = 39 mice; Control group, n = 12 units, n = 38 mice). The results confirmed our previous finding that adult offspring exposed to MIA prenatally had significant global DNA hypomethylation. Furthermore, genes linked to synaptic plasticity were over-represented among differentially methylated genes following MIA. More than 80% of MIA-induced hypomethylated sites, including those affecting chromatin state and MECP2 binding, were stabilised by the n-3 PUFA intervention. MIA resulted in increased expression of two of the 'top five' genes identified from an integrated analysis of DMRs, DHSs and MECP2 binding sites, namely Abat (t = 2.46, p < 0.02) and Gnas9 (t = 2.96, p < 0.01), although these changes were not stabilised by dietary intervention. Thus, prenatal MIA exposure impacts upon the epigenomic regulation of gene pathways linked to neurodevelopmental conditions; and many of the changes can be attenuated by a low-cost dietary intervention.

Relationship between executive function, attachment style, and psychotic like experiences in typically developing youth

Psychotic like experiences (PLE's) are common in the general population, particularly during adolescence, which has generated interest in how PLE's emerge, and the extent to which they reflect either risk for, or resilience to, psychosis. The "attachment-developmental-cognitive" (ADC) model is one effort to model the effect of risk factors on PLEs. The ADC model proposes attachment insecurity as an early environmental insult that can contribute to altered neurodevelopment, increasing the likelihood of PLE's and psychosis. In particular, early-life attachment disruptions may negatively impact numerous aspects of executive function (EF), including behavioral inhibition and emotion regulation. Yet despite the relationship of disrupted attachment to EF impairments, no studies have examined how these factors may combine to contribute to PLE's in adolescents. Here, we examined the relative contributions of daily-life EF and attachment difficulties (avoidance and anxiety) to PLEs in typically developing youth (N=52; ages 10-21). We found that EF deficits and high attachment insecurity both accounted for a significant proportion of the variance in PLE's, and interacted to predict PLE manifestation. Specifically, positive PLEs were predicted by greater trouble monitoring behavioral impact, less difficulty completing tasks, greater difficulty regulating emotional reactions, greater difficulty controlling impulses and higher attachment anxiety. Negative PLEs were predicted by greater difficulty in alternating attention, transitioning across situations, and regulating emotional reactions as well as higher attachment anxiety. These results are consistent with the ADC model, providing evidence that early-life attachment disruptions may impact behavioral regulation and emotional control, which together may contribute to PLEs.

Structural and functional alterations in the brain during working memory in medication-naïve patients at clinical high-risk for psychosis

Several previous studies suggest that clinical high risk for psychosis (CHR) is associated with prefrontal functional abnormalities and more widespread reduced grey matter in prefrontal, temporal and parietal areas. We investigated neural correlates to CHR in medication-naïve patients. 41 CHR patients and 37 healthy controls were examined with 1.5 Tesla MRI, yielding functional scans while performing an N-back task and structural T1-weighted brain images. Functional and structural data underwent automated preprocessing steps in SPM and Freesurfer, correspondingly. The groups were compared employing mass-univariate strategy within the generalized linear modelling framework. CHR demonstrated reduced suppression of the medial temporal lobe (MTL) regions during n-back task. We also found that, consistent with previous findings, CHR subjects demonstrated thinning in prefrontal, cingulate, insular and inferior temporal areas, as well as reduced hippocampal volumes. The present findings add to the growing evidence of specific structural and functional abnormalities in the brain as potential neuroimaging markers of psychosis vulnerability.

Prevalence of psychotic-like experiences and their correlations with internalizing problems: A study of early adolescents in rural area in Karawang, Indonesia

INTRODUCTION

Adolescents who live in rural areas have been found to experience more mental health problems than those who live in urban areas. In Indonesia, adolescents who live in rural areas have limited facilities to access mental health services. On the other hand, there is still a strong belief in the rural communities that mental health problems are the consequence of demonic possession, having committed a sin, lack of faith, etc. Rural communities tend to seek traditional remedies such as advice from traditional healers or witchdoctors. Unfortunately, previous studies have indicated that the onset of most mental health problems is during adolescence, and this includes psychotic symptoms that are often manifested as psychotic-like experiences (PLEs).

METHODS

The Strength and Difficulties Questionnaire was used to examine internalizing problems. PLEs were used to examine psychotic symptoms. Data were collected in 3 junior high schools in Karawang. A total of 270 adolescents (aged between 11 and 16 years old) who live in the rural area in Karawang participated in this research.

RESULTS

The study found that the prevalence of adolescents with at least 2 symptoms of PLEs was 7%. The result of the study indicated that there is no significant correlation between psychotic-like experiences and internalizing problems (r = .075, P = .22).

DISCUSSION

PLEs significantly correlated with peer-relationship problems rather than with internalizing problems. Further investigation is needed to examine the factors that contribute to PLEs in rural settings.

Stressful life events during adolescence and risk for externalizing and internalizing psychopathology: a meta-analysis

The main objective of the present research was to analyze the relations between stressful life events and the externalizing and internalizing spectra of psychopathology using meta-analytical procedures. After removing the duplicates, a total of 373 papers were found in a literature search using several bibliographic databases, such as the PsycINFO, Medline, Scopus, and Web of Science. Twenty-seven studies were selected for the meta-analytical analysis after applying different inclusion and exclusion criteria in different phases. The statistical procedure was performed using a random/mixed-effects model based on the correlations found in the studies. Significant positive correlations were found in cross-sectional and longitudinal studies. A transactional effect was then found in the present study. Stressful life events could be a cause, but also a consequence, of psychopathological spectra. The level of controllability of the life events did not affect the results. Special attention should be given to the usage of stressful life events in gene-environment interaction and correlation studies, and also for clinical purposes.

Adolescence and Reward: Making Sense of Neural and Behavioral Changes Amid the Chaos

Adolescence is a time of significant neural and behavioral change with remarkable development in social, emotional, and cognitive skills. It is also a time of increased exploration and risk-taking (e.g., drug use). Many of these changes are thought to be the result of increased reward-value coupled with an underdeveloped inhibitory control, and thus a hypersensitivity to reward. Perturbations during adolescence can alter the developmental trajectory of the brain, resulting in long-term alterations in reward-associated behaviors. This review highlights recent developments in our understanding of how neural circuits, pubertal hormones, and environmental factors contribute to adolescent-typical reward-associated behaviors with a particular focus on sex differences, the medial prefrontal cortex, social reward, social isolation, and drug use. We then introduce a new approach that makes use of natural adaptations of seasonally breeding species to investigate the role of pubertal hormones in adolescent development. This research has only begun to parse out contributions of the many neural, endocrine, and environmental changes to the heightened reward sensitivity and increased vulnerability to mental health disorders that characterize this life stage.

Prefrontal mechanisms of comorbidity from a transdiagnostic and ontogenic perspective

Accumulating behavioral and genetic research suggests that most forms of psychopathology share common genetic and neural vulnerabilities and are manifestations of a relatively few core underlying processes. These findings support the view that comorbidity mostly arises, not from true co-occurrence of distinct disorders, but from the behavioral expression of shared vulnerability processes across the life span. The purpose of this review is to examine the role of the prefrontal cortex (PFC) in the shared vulnerability mechanisms underlying the clinical phenomena of comorbidity from a transdiagnostic and ontogenic perspective. In adopting this perspective, we suggest complex transactions between neurobiologically rooted vulnerabilities inherent in PFC circuitry and environmental factors (e.g., parenting, peers, stress, and substance use) across development converge on three key PFC-mediated processes: executive functioning, emotion regulation, and reward processing. We propose that individual differences and impairments in these PFC-mediated functions provide intermediate mechanisms for transdiagnostic symptoms and underlie behavioral tendencies that evoke and interact with environmental risk factors to further potentiate vulnerability.

Adolescent maturation of the relationship between cortical gyrification and cognitive ability

There are changes to the degree of cortical folding from gestation through adolescence into young adulthood. Recent evidence suggests that degree of cortical folding is linked to individual differences in general cognitive ability in healthy adults. However, it is not yet known whether age-related cortical folding changes are related to maturation of specific cognitive abilities in adolescence. To address this, we examined the relationship between frontoparietal cortical folding as measured by a Freesurfer-derived local gyrification index (lGI) and performance on subtests from the Wechsler Abbreviated Scale of Intelligence and scores from Conner's Continuous Performance Test-II in 241 healthy adolescents (ages 12-25 years). We hypothesized that age-related lGI changes in the frontoparietal cortex would contribute to cognitive development. A secondary goal was to explore if any gyrification-cognition relationships were either test-specific or sex-specific. Consistent with previous studies, our results showed a reduction of frontoparietal local gyrification with age. Also, as predicted, all cognitive test scores (i.e., Vocabulary, Matrix Reasoning, the CPT-II Commission, Omission, Variabiltiy, d') showed age × cognitive ability interaction effects in frontoparietal and temporoparietal brain regions. Mediation analyses confirmed a causal role of age-related cortical folding changes only for CPT-II Commission errors. Taken together, the results support the functional significance of cortical folding, as well as provide the first evidence that cortical folding maturational changes play a role in cognitive development.

The relations of age and pubertal development with cortisol and daily stress in youth at clinical risk for psychosis

BACKGROUND

Prodromal syndromes often begin in adolescence - a period of neurodevelopmental changes and heightened stress sensitivity. Research has shown elevated stress and cortisol in individuals at clinical high risk (CHR) for psychosis. This cross-sectional study examined relations of age and pubertal status with cortisol and self-reported stress in healthy controls (HCs) and CHR adolescents. It was hypothesized that the relations of age and pubertal stage with cortisol and stress would be more pronounced in CHR youth.

METHODS

Participants were 93 HCs and 348 CHR adolescents from the North American Prodrome Longitudinal Study (NAPLS). At baseline, measures of stress (Daily Stress Inventory - DSI), Tanner stage (TS), and salivary cortisol were obtained.

RESULTS

ANCOVA revealed increased DSI scores with age for both groups, and higher DSI scores in CHR adolescents than HCs, with a more pronounced difference for females. Contrary to prediction, with age controlled, HCs showed greater TS-related DSI increases. Analysis of cortisol showed no significant interactions, but a main effect of age and a trend toward higher cortisol in the CHR group. Correlations of cortisol with TS were higher in HC than CHR group.

CONCLUSIONS

Stress measures increased with age in HC and CHR adolescents, and DSI scores also increased with TS in HCs. The results do not support a more pronounced age or TS increase in stress measures in CHR adolescents, but instead suggest that stress indices tend to be elevated earlier in adolescence in the CHR group. Potential determinants of findings and future directions are discussed.

A Role for the Transcription Factor Nk2 Homeobox 1 in Schizophrenia: Convergent Evidence from Animal and Human Studies

Schizophrenia is a highly heritable disorder with diverse mental and somatic symptoms. The molecular mechanisms leading from genes to disease pathology in schizophrenia remain largely unknown. Genome-wide association studies (GWASs) have shown that common single-nucleotide polymorphisms associated with specific diseases are enriched in the recognition sequences of transcription factors that regulate physiological processes relevant to the disease. We have used a “bottom-up” approach and tracked a developmental trajectory from embryology to physiological processes and behavior and recognized that the transcription factor NK2 homeobox 1 (NKX2-1) possesses properties of particular interest for schizophrenia. NKX2-1 is selectively expressed from prenatal development to adulthood in the brain, thyroid gland, parathyroid gland, lungs, skin, and enteric ganglia, and has key functions at the interface of the brain, the endocrine-, and the immune system. In the developing brain, NKX2-1-expressing progenitor cells differentiate into distinct subclasses of forebrain GABAergic and cholinergic neurons, astrocytes, and oligodendrocytes. The transcription factor is highly expressed in mature limbic circuits related to context-dependent goal-directed patterns of behavior, social interaction and reproduction, fear responses, responses to light, and other homeostatic processes. It is essential for development and mature function of the thyroid gland and the respiratory system, and is involved in calcium metabolism and immune responses. NKX2-1 interacts with a number of genes identified as susceptibility genes for schizophrenia. We suggest that NKX2-1 may lie at the core of several dose dependent pathways that are dysregulated in schizophrenia. We correlate the symptoms seen in schizophrenia with the temporal and spatial activities of NKX2-1 in order to highlight promising future research areas.

Genetic influences on pubertal development and links to behavior problems

Genetic influences on adolescent psychological development are likely to be mediated and moderated by pubertal hormones. Combining genetic analyses with advanced models of pubertal development, we extended work on the measurement and psychological significance of puberty. We examined how genetic and environmental influences on puberty vary by the way that development is described (logistic versus linear models versus traditional methods) and the different aspects of puberty (adrenarche vs. gonadarche), and how genes and environment contribute to the covariation between different descriptions and aspects of puberty, and between pubertal development and behavior problems (substance use, age at sexual initiation). We also considered how puberty moderated the heritability of psychological outcomes (internalizing and externalizing problems), and sex differences. Participants from the Colorado Longitudinal Twin Study (403 girls, 395 boys) reported their pubertal development annually from ages 9 through 15; they and their parents reported their behavior in mid-to-late adolescence. There was a large genetic contribution to pubertal timing for both sexes no matter how it was measured, but findings for pubertal tempo varied by method. Genetic covariation accounted for most of the phenotypic correlations among different indicators of pubertal timing, and between pubertal timing and psychological outcome. We consider the implications of our results for understanding how pubertal hormones mediate or moderate genetic and environmental influences on psychological development.

Oxytocin, testosterone, and human social cognition

I describe an integrative social-evolutionary model for the adaptive significance of the human oxytocinergic system. The model is based on a role for this hormone in the generation and maintenance of social familiarity and affiliation across five homologous, functionally similar, and sequentially co-opted contexts: mothers with offspring, female and male mates, kin groups, individuals with reciprocity partners, and individuals within cooperating and competing social groups defined by culture. In each situation, oxytocin motivates, mediates and rewards the cognitive and behavioural processes that underlie the formation and dynamics of a more or less stable social group, and promotes a relationship between two or more individuals. Such relationships may be positive (eliciting neurological reward, reducing anxiety and thus indicating fitness-enhancing effects), or negative (increasing anxiety and distress, and thus motivating attempts to alleviate a problematic, fitness-reducing social situation). I also present evidence that testosterone exhibits opposite effects from oxytocin on diverse aspects of cognition and behaviour, most generally by favouring self-oriented, asocial and antisocial behaviours. I apply this model for effects of oxytocin and testosterone to understanding human psychological disorders centrally involving social behaviour. Reduced oxytocin and higher testosterone levels have been associated with under-developed social cognition, especially in autism. By contrast, some combination of oxytocin increased above normal levels, and lower testosterone, has been reported in a notable number of studies of schizophrenia, bipolar disorder and depression, and, in some cases, higher oxytocin involves maladaptively 'hyper-developed' social cognition in these conditions. This pattern of findings suggests that human social cognition and behaviour are structured, in part, by joint and opposing effects of oxytocin and testosterone, and that extremes of such joint effects partially mediate risks and phenotypes of autism and psychotic-affective conditions. These considerations have direct implications for the development of therapies for alleviating disorders of social cognition, and for understanding how such disorders are associated with the evolution of human cognitive-affective architecture.

The importance of puberty for adolescent development: conceptualization and measurement

How and why are teenagers different from children and adults? A key question concerns the ways in which pubertal development shapes psychological changes in adolescence directly through changes to the brain and indirectly through the social environment. Empirical work linking pubertal development to adolescent psychological function draws from several different perspectives, often with varying approaches and a focus on different outcomes and mechanisms. The main themes concern effects of atypical pubertal timing on behavior problems during adolescence, effects of pubertal status (and associated hormones) on normative changes in behaviors that can facilitate or hinder development (especially risk-taking, social reorientation, and stress responsivity), and the role of puberty in triggering psychopathology in vulnerable individuals. There is also interest in understanding the ways in which changes in the brain reflect pubertal processes and underlie psychological development in adolescence. In this chapter, we consider the ways that puberty might affect adolescent psychological development, and why this is of importance to developmentalists. We describe the processes of pubertal development; summarize what is known about pubertal influences on adolescent development; consider the assumptions that underlie most work and the methodological issues that affect the interpretation of results; and propose research directions to help understand paths from puberty to behavior. Throughout, we emphasize the importance of pubertal change in all aspects of psychological development, and the ways in which puberty represents an opportunity to study the interplay of biological and social influences.

Analyzing the influence of BDNF heterozygosity on spatial memory response to 17β-estradiol

The recent use of estrogen-based therapies as adjunctive treatments for the cognitive impairments of schizophrenia has produced promising results; however the mechanism behind estrogen-based cognitive enhancement is relatively unknown. Brain-derived neurotrophic factor (BDNF) regulates learning and memory and its expression is highly responsive to estradiol. We recently found that estradiol modulates the expression of hippocampal parvalbumin-positive GABAergic interneurons, known to regulate neuronal synchrony and cognitive function. What is unknown is whether disruptions to the aforementioned estradiol-parvalbumin pathway alter learning and memory, and whether BDNF may mediate these events. Wild-type (WT) and BDNF heterozygous (+/-) mice were ovariectomized (OVX) at 5 weeks of age and simultaneously received empty, estradiol- or progesterone-filled implants for 7 weeks. At young adulthood, mice were tested for spatial and recognition memory in the Y-maze and novel-object recognition test, respectively. Hippocampal protein expression of BDNF and GABAergic interneuron markers, including parvalbumin, were assessed. WT OVX mice show impaired performance on Y-maze and novel-object recognition test. Estradiol replacement in OVX mice prevented the Y-maze impairment, a Behavioral abnormality of dorsal hippocampal origin. BDNF and parvalbumin protein expression in the dorsal hippocampus and parvalbumin-positive cell number in the dorsal CA1 were significantly reduced by OVX in WT mice, while E2 replacement prevented these deficits. In contrast, BDNF(+/-) mice showed either no response or an opposite response to hormone manipulation in both behavioral and molecular indices. Our data suggest that BDNF status is an important biomarker for predicting responsiveness to estrogenic compounds which have emerged as promising adjunctive therapeutics for schizophrenia patients.

Modeling pubertal timing and tempo and examining links to behavior problems

Research on the role of puberty in adolescent psychological development requires attention to the meaning and measurement of pubertal development. Particular questions concern the utility of self-report, the need for complex models to describe pubertal development, the psychological significance of pubertal timing vs. tempo, and sex differences in the nature and psychological significance of pubertal development. We used longitudinal self-report data to model linear and logistic trajectories of pubertal development, and used timing and tempo estimates from these models, and from traditional approaches (age at menarche and time from onset of breast development to menarche), to predict psychological outcomes of internalizing and externalizing behavior problems, and early sexual activity. Participants (738 girls, 781 boys) reported annually from ages 9 through 15 on their pubertal development, and they and their parents reported on their behavior in mid-to-late adolescence and early adulthood. Self-reports of pubertal development provided meaningful data for both boys and girls, producing good trajectories, and estimates of individuals' pubertal timing and tempo. A logistic model best fit the group data. Pubertal timing was estimated to be earlier in the logistic compared to linear model, but linear, logistic, and traditional estimates of pubertal timing correlated highly with each other and similarly with psychological outcomes. Pubertal tempo was not consistently estimated, and associations of tempo with timing and with behavior were model dependent. Advances in modeling facilitate the study of some questions about pubertal development, but assumptions of the models affect their utility in psychological studies.

Developmental mechanisms in the prodrome to psychosis

Psychotic disorders continue to be among the most disabling and scientifically challenging of all mental illnesses. Accumulating research findings suggest that the etiologic processes underlying the development of these disorders are more complex than had previously been assumed. At the same time, this complexity has revealed a wider range of potential options for preventive intervention, both psychosocial and biological. In part, these opportunities result from our increased understanding of the dynamic and multifaceted nature of the neurodevelopmental mechanisms involved in the disease process, as well as the evidence that many of these entail processes that are malleable. In this article, we review the burgeoning research literature on the prodrome to psychosis, based on studies of individuals who meet clinical high risk criteria. This literature has examined a range of factors, including cognitive, genetic, psychosocial, and neurobiological. We then turn to a discussion of some contemporary models of the etiology of psychosis that emphasize the prodromal period. These models encompass the origins of vulnerability in fetal development, as well as postnatal stress, the immune response, and neuromaturational processes in adolescent brain development that appear to go awry during the prodrome to psychosis. Then, informed by these neurodevelopmental models of etiology, we turn to the application of new research paradigms that will address critical issues in future investigations. It is expected that these studies will play a major role in setting the stage for clinical trials aimed at preventive intervention.