Exploring the relationship between frequent cannabis use, belief updating under uncertainty and psychotic-like symptoms.

Background: Cannabis users present an important group for investigating putative mechanisms underlying psychosis, as cannabis-use is associated with an increased risk of psychosis. Recent work suggests that alterations in belief-updating under uncertainty underlie psychosis. We therefore compared belief updating under uncertainty between cannabis and non-cannabis users.

Distinct alterations in probabilistic reversal learning across at-risk mental state, first episode psychosis and persistent schizophrenia.

We used a probabilistic reversal learning task to examine prediction error-driven belief updating in three clinical groups with psychosis or psychosis-like symptoms. Study 1 compared people with at-risk mental state and first episode psychosis (FEP) to matched controls. Study 2 compared people diagnosed with treatment-resistant schizophrenia (TRS) to matched controls.

Towards a scalable approach to assess speech organization across the psychosis-spectrum -online assessment in conjunction with automated transcription and extraction of speech measures.

Automatically extracted measures of speech constitute a promising marker of psychosis as disorganized speech is associated with psychotic symptoms and predictive of psychosis-onset. The potential of speech markers is, however, hampered by (i) lengthy assessments in laboratory settings and (ii) manual transcriptions. We investigated whether a short, scalable data collection (online) and processing (automated transcription) procedure would provide data of sufficient quality to extract previously validated speech measures.

Automated analysis of speech as a marker of sub-clinical psychotic experiences.

Automated speech analysis techniques, when combined with artificial intelligence and machine learning, show potential in capturing and predicting a wide range of psychosis symptoms, garnering attention from researchers. These techniques hold promise in predicting the transition to clinical psychosis from at-risk states, as well as relapse or treatment response in individuals with clinical-level psychosis. However, challenges in scientific validation hinder the translation of these techniques into practical applications.

The Placebo Effect in Psychosis: Why It Matters and How to Measure It.

Psychosis is characterized by unusual percepts and beliefs in the form of hallucinations and delusions. Antipsychotic medication, the primary treatment for psychosis, is often ineffective and accompanied by severe side effects, but research has not identified an effective alternative in several decades. One reason that clinical trials fail is that patients with psychosis tend to show a significant therapeutic response to inert control treatments, known as the placebo effect, which makes it difficult to distinguish drug effects from placebo effects.

Online speech assessment of the psychotic spectrum: Exploring the relationship between overlapping acoustic markers of schizotypy, depression and anxiety.

Background: Remote assessment of acoustic alterations in speech holds promise to increase scalability and validity in research across the psychosis spectrum. A feasible first step in establishing a procedure for online assessments is to assess acoustic alterations in psychometric schizotypy. However, to date, the complex relationship between alterations in speech related to schizotypy and those related to comorbid conditions such as symptoms of depression and anxiety has not been investigated.

Semantic Speech Networks Linked to Formal Thought Disorder in Early Psychosis.

Background And Hypothesis: Mapping a patient's speech as a network has proved to be a useful way of understanding formal thought disorder in psychosis. However, to date, graph theory tools have not explicitly modelled the semantic content of speech, which is altered in psychosis.

Study Design: We developed an algorithm, "netts," to map the semantic content of speech as a network, then applied netts to construct semantic speech networks for a general population sample (N = 436), and a clinical sample comprising patients with first episode psychosis (FEP), people at clinical high risk of psychosis (CHR-P), and healthy controls (total N = 53).

Belief updating in psychosis, depression and anxiety disorders: A systematic review across computational modelling approaches.

Alterations in belief updating are proposed to underpin symptoms of psychiatric illness, including psychosis, depression, and anxiety. Key parameters underlying belief updating can be captured using computational modelling techniques, aiding the identification of unique and shared deficits, and improving diagnosis and treatment. We systematically reviewed research that applied computational modelling to probabilistic tasks measuring belief updating in stable and volatile (changing) environments, across clinical and subclinical psychosis (n = 17), anxiety (n = 9), depression (n = 9) and transdiagnostic samples (n = 9).

Current treatment practice of functional abdominal pain disorders in children: A multicenter survey.

Background: Approximately 90% of the children with chronic abdominal pain are diagnosed as having functional abdominal pain disorder (FAPD). The Dutch guideline "functional abdominal pain" provides a stepwise approach to treat FAPD. The aim of this survey was twofold first, to determine adherence to the Dutch guideline, and second to determine current management of FAPDs in clinical practice.

Characterizing cerebral metabolite profiles in anorexia and bulimia nervosa and their associations with habitual behavior.

Anorexia nervosa (AN) and bulimia nervosa (BN) are associated with altered brain structure and function, as well as increased habitual behavior. This neurobehavioral profile may implicate neurochemical changes in the pathogenesis of these illnesses. Altered glutamate, myo-inositol and N-acetyl aspartate (NAA) concentrations are reported in restrictive AN, yet whether these extend to binge-eating disorders, or relate to habitual traits in affected individuals, remains unknown.

Subcortical volume reduction and cortical thinning 3 months after switching to clozapine in treatment resistant schizophrenia.

The neurobiological effects of clozapine are under characterised. We examined the effects clozapine treatment on subcortical volume and cortical thickness and investigated whether macrostructural changes were linked to alterations in glutamate or N-acetylaspartate (NAA). Data were acquired in 24 patients with treatment-resistant schizophrenia before and 12 weeks after switching to clozapine.

Natural Language Processing markers in first episode psychosis and people at clinical high-risk.

Recent work has suggested that disorganised speech might be a powerful predictor of later psychotic illness in clinical high risk subjects. To that end, several automated measures to quantify disorganisation of transcribed speech have been proposed. However, it remains unclear which measures are most strongly associated with psychosis, how different measures are related to each other and what the best strategies are to collect speech data from participants.

Cannabinoids, reward processing, and psychosis.

Background: Evidence suggests that an overlap exists between the neurobiology of psychotic disorders and the effects of cannabinoids on neurocognitive and neurochemical substrates involved in reward processing.

Aims: We investigate whether the psychotomimetic effects of delta-9-tetrahydrocannabinol (THC) and the antipsychotic potential of cannabidiol (CBD) are underpinned by their effects on the reward system and dopamine.

Methods: This narrative review focuses on the overlap between altered dopamine signalling and reward processing induced by cannabinoids, pre-clinically and in humans.

Exclusive enteral nutrition mediates gut microbial and metabolic changes that are associated with remission in children with Crohn's disease.

A nutritional intervention, exclusive enteral nutrition (EEN) can induce remission in patients with pediatric Crohn's disease (CD). We characterized changes in the fecal microbiota and metabolome to identify the mechanism of EEN. Feces of 43 children were collected prior, during and after EEN.

Can 2 Different Fecal Calprotectin Assays be Used Interchangeably in IBD Treatment?

Background: Fecal calprotectin (FC) is a biomarker for inflammation in inflammatory bowel disease (IBD). Interpretation of results can be complicated because of the use of different assays to determine FC.

Goals: To assess the agreement between 2 different assays for determining FC in patients with IBD.

Lower speech connectedness linked to incidence of psychosis in people at clinical high risk.

Background: Formal thought disorder is a cardinal feature of psychotic disorders, and is also evident in subtle forms before psychosis onset in individuals at clinical high-risk for psychosis (CHR-P). Assessing speech output or assessing expressive language with speech as the medium at this stage may be particularly useful in predicting later transition to psychosis.

Method: Speech samples were acquired through administration of the Thought and Language Index (TLI) in 24 CHR-P participants, 16 people with first-episode psychosis (FEP) and 13 healthy controls.

Precision weighting of cortical unsigned prediction error signals benefits learning, is mediated by dopamine, and is impaired in psychosis.

Recent theories of cortical function construe the brain as performing hierarchical Bayesian inference. According to these theories, the precision of prediction errors plays a key role in learning and decision-making, is controlled by dopamine and contributes to the pathogenesis of psychosis. To test these hypotheses, we studied learning with variable outcome-precision in healthy individuals after dopaminergic modulation with a placebo, a dopamine receptor agonist bromocriptine or a dopamine receptor antagonist sulpiride (dopamine study n = 59) and in patients with early psychosis (psychosis study n = 74: 20 participants with first-episode psychosis, 30 healthy controls and 24 participants with at-risk mental state attenuated psychotic symptoms).

Dopamine, Prediction Error and Beyond.

A large body of work has linked dopaminergic signaling to learning and reward processing. It stresses the role of dopamine in reward prediction error signaling, a key neural signal that allows us to learn from past experiences, and that facilitates optimal choice behavior. Latterly, it has become clear that dopamine does not merely code prediction error size but also signals the difference between the expected value of rewards, and the value of rewards actually received, which is obtained through the integration of reward attributes such as the type, amount, probability and delay.

Quality of life and colorectal function in Crohn's disease patients that underwent ileocecal resection during childhood.

Psychosocial and functional outcomes after intestinal resection in pediatric Crohn's disease (CD) are lacking. Therefore, we (I) assessed health-related quality of life (HRQOL), colorectal function, and satisfaction with surgery and (II) investigated their relationship with surgical outcomes, after ileocecal resection for CD. Crohn's patients that underwent ileocecal resection during childhood were included.

Diet and Anthropometrics of Children With Inflammatory Bowel Disease: A Comparison With the General Population.

Background: There is a lack of knowledge regarding the diet of children with inflammatory bowel disease (IBD). Therefore, we investigated dietary intake in pediatric IBD compared to the general population and assessed anthropometrics and food avoidance.

Methods: In this cross-sectional cohort study, patients younger than 18 years with IBD were included (2014-2017).

Associations between cortical thickness, structural connectivity and severity of dimensional bulimia nervosa symptomatology.

Bulimia nervosa (BN) is a psychiatric illness defined by preoccupation with body image (cognitive 'symptoms'), binge eating and compensatory behaviors. Although diagnosed BN has been related to grey matter alterations, characterization of brain structure in women with a range of BN symptoms has not been made. This study examined whether cortical thickness (CT) values scaled with severity of BN cognitions in 33 women with variable BN pathology.

Fecal Amino Acid Analysis Can Discriminate De Novo Treatment-Naïve Pediatric Inflammatory Bowel Disease From Controls.

Objectives: Endoscopy remains mandatory in the diagnostic work-up of inflammatory bowel disease (IBD), but is a costly and invasive procedure. Identification of novel, noninvasive, diagnostic biomarkers remains a priority. The aim of the present study was to explore the potential of fecal amino acid composition as diagnostic biomarker for pediatric IBD.

Parental Distress and Quality of Life in Pediatric Inflammatory Bowel Disease: Implications for the Outpatient Clinic.

Objectives: The interrelation between the course of inflammatory bowel disease (IBD) in children and parent's distress, and the subsequent impact this may have on health-related quality of life (HRQOL) of the child is unclear. Therefore, we investigated patient's HRQOL and parental distress and the association between the course of IBD, parental distress, and HRQOL of pediatric patients with IBD.

Methods: Pediatric patients with IBD (8-18 years) and parents were invited.