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Background and Hypothesis While literature indicates that culture modulates phenomenological characteristics of hallucinations in schizophrenia-spectrum disorders, little is known about the extent culture modulates these characteristics in nonclinical samples. Study Design We compared lifetime prevalence, age of onset, and phenomenology of hallucinations as assessed with the Questionnaire for Psychotic Experiences between samples of nonclinical participants used from the Netherlands (N = 2999) and Qatar (N = 2999). While participant recruitment differed between the 2 countries, the samples were relatively equal in terms of demographic factors. Study Results Our findings indicate that the lifetime prevalence of tactile and olfactory hallucinations are the same across countries. However, the prevalence of auditory hallucinations (AH) and visual hallucinations (VH) were twice as high in the Dutch sample. The reported age of onset for auditory and tactile hallucinations was younger for the Dutch sample. Findings from the measurement invariance supported cross-cultural comparisons with exception for duration, distress, and insight. Qatar’s and Dutch participants reported similar valence and extent of interaction with AH and VH. However, compared to those in the Netherlands, participants from Qatar reported significantly more impact on daily functioning and a higher prevalence of receiving commands from hallucinations in the past week. Conclusions While AH and VH were more often reported in the Dutch sample, participants in Qatar generally had higher mean factor scores for past week AH and VH than in the Netherlands. The phenomenology of hallucinations in the Qatar sample was of greater clinical relevance, with potentially important implications for early screening and prevention.

Religiosity is a multidimensional construct known to influence the occurrence of hallucinations. However, it remains unknown how different religiosity types affect clinically relevant phenomenological features of hallucinations. Therefore, we wished to explore associations between intrinsic and extrinsic (non-organizational and organizational) religiosity and hallucinations severity, distress or impact on daily function in a non-clinical Muslim population. We recruited a representative sample of full-time students at Qatar's only national university via systematic random sampling and administered the Questionnaire of Psychotic Experiences online. The study design was cross-sectional. Using structural equation modeling, we estimated effects of the religiosity types on hallucinations severity, distress or impact on daily function in the past week while accounting for sociodemographic variables, anxiety, depressive symptoms, and, delusions. Extrinsic non-organizational religiosity (ENORG) was associated with experiencing reduced distress or impact on daily function from hallucinations both directly and indirectly through intrinsic religiosity. In contrast, extrinsic non-organizational religiosity (EORG) was associated with increased hallucinations distress or impact albeit only through higher intrinsic religiosity. We found no association between any religiosity types and hallucinations severity. Younger and married participants from lower socio-economic class had comparatively more severe hallucinations and more distress from them. Qatari nationality was positively associated EORG and negatively associated with hallucinations distress or impact. Evidence of differential associations between the religiosity types, socioeconomic and cultural groups, and distress or impact from past week's hallucinations supports the importance of alignment between religious, mental health, and well-being education.

Background\ud \ud Prevalence trends from Arabic speaking countries on psychiatric symptoms before and after COVID-19 pandemic is lacking. We estimated the point prevalence and change in depression and anxiety symptoms scores in relation to sociodemographic variables following the resolution of the first wave in Qatar compared with before the pandemic.\ud \ud \ud \ud Methods\ud \ud We conducted a trend analysis using repeated nationally representative cross-sectional surveys spanning 2017, 2018, 2020/2021 and using the Physician Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) to assess depressive and anxiety symptoms. Negative binomial regression modelled changes in these symptoms in relation sociodemographics and survey year.\ud \ud \ud \ud Results\ud \ud The two-week prevalence of depressive symptoms (≥10 on the PHQ-9) was 6.6% in 2017 and 6.5% in 2020/2021 (p = 0.986). The two-week prevalence of anxiety symptoms (≥10 or higher on the GAD-7) was 3.6% in 2018 and 5.1% in 2020/2021 (p = 0.062). The data for 2020/21 showed a 35.1% and 29.2% decrease in depression and anxiety symptoms scores compared to pre-pandemic years (2017/2018) after adjusting for sociodemographic factors.\ud \ud \ud \ud Limitations\ud \ud Screening tools rather than structured interviews were to assess depressive and anxiety symptoms.\ud \ud \ud \ud Conclusions\ud \ud Prevalence for depression and anxiety post the first COVID wave did not differ significantly to pre-pandemic estimates. The end of the first wave of the pandemic had a ‘levelling’ effect on these symptoms and their associations with traditional sociodemographic risk factors. The 2020/21 depression and anxiety symptoms scores remained high for Qataris and Arabs, suggesting that these cultural groups may benefit most from public mental health interventions.

Background Schizophrenia endophenotypes may help elucidate functional effects of genetic risk variants in multiply affected consanguineous families that segregate recessive risk alleles of large effect size. We studied the association between a schizophrenia risk locus involving a 6.1Mb homozygous region on chromosome 13q22–31 in a consanguineous multiplex family and cognitive functioning, haemodynamic response and white matter integrity using neuroimaging. Methods We performed CANTAB neuropsychological testing on four affected family members (all homozygous for the risk locus), ten unaffected family members (seven homozygous and three heterozygous) and ten healthy volunteers, and tested neuronal responses on fMRI during an n-back working memory task, and white matter integrity on diffusion tensor imaging (DTI) on four affected and six unaffected family members (four homozygous and two heterozygous) and three healthy volunteers. For cognitive comparisons we used a linear mixed model (Kruskal–Wallis) test, followed by posthoc Dunn's pairwise tests with a Bonferroni adjustment. For fMRI analysis, we counted voxels exceeding the p < 0.05 corrected threshold. DTI analysis was observational. Results Family members with schizophrenia and unaffected family members homozygous for the risk haplotype showed attention (p < 0.01) and working memory deficits (p < 0.01) compared with healthy controls; a neural activation laterality bias towards the right prefrontal cortex (voxels reaching p < 0.05, corrected) and observed lower fractional anisotropy in the anterior cingulate cortex and left dorsolateral prefrontal cortex. Conclusions In this family, homozygosity at the 13q risk locus was associated with impaired cognition, white matter integrity, and altered laterality of neural activation.

We show a fundamental unity underlying the main alternative approaches to counter-factual and subjunctive conditionals. The unifying idea is that of a family of partitions. The theory is then applied to counter-factuals in decision theory and in normal form and extensive form games. The structure of the decision problem, or of the game, naturallydetermines the partitions used in interpreting these conditionals.

s and the Evans Argument (and its Successors). Any theory that allows for indeterminacy in the world places constraints on how language might relate to the world. Suppose that our language has (at least) the syntax of the predicate calculus with identity, and that it contains some predicates that stand for properties, and some names that stand for objects. Suppose further that an atomic sentence of the form Fa is true if what a stands for definitely has the property that F stands for, false if what a stands for definitely lacks the property that F stands for, and otherwise indeterminate. Now suppose, in addition, that we have in this language some lambda abstracts that form complex predicates, such as 'Xx[Ax & Bx]', i.e. the predicate of 'being both A and B.' If the language is sufficiently rich then we cannot assume that any such abstract refers to a property whose application to objects is perfectly characterized in the usual way by lambda abstraction, the principle that '?D(a)' is interchangeable with 'Xx[

The previous essay outlines an account of indeterminate identity, and offers some preliminary illustrations of its application to puzzles about identity through time. We wish now to consider an application to a particular, rigorously formulated theory. The theory of sets is especially apt for this role, since it brings into prominence the Quinean theme of identity conditions: “No entity without identity.” At the same time, our discussion will confront what I will call the Basic Objection to many-valued theories, also due to Quine: that they are simply too messy.1

In [Woodruff 1984] I showed that the supervaluation semantics introduced by [Van Fraassen 1966a, b] for Lambert’s system of free logic [Meyer and Lambert 1968] failed to have certain metatheoretic properties (compactness, upward and downward Lowenheim-Skolem, strong completeness and recursive axiomatizability) which attach to ordinary first-order logic. I also introduced the idea of secondary supervaluations, in which the class of conventions for asigning truth values to formulas with non-designating terms was restricted in some way or another. I was able to show that for a particular such restriction, the falsity condition (R(cx) false of all x when c doesn’t denote), the desirable properties were regained. I speculated that the indifference condition (R(cx) true either of all or of no xwhen cdoesn’t denote) would also suffice, and might be necessary.1

A system of modal logic with the λ operator is proposed, and proved complete. In contrast with a previous one by Stalnaker and Thomason, this system does not require two categories of singular terms.

Given Tarski’s familiar treatment of the semantic paradoxes, no formal language can adequately represent its own truth-concept.1 But natural languages do, apparently, express their own truth-concepts and this fact alone has been enough to motivate some to seek alternative treatments of the paradoxes. In this paper we demonstrate that a language construed according to the ‘category’ approach,2 modified in certain respects, can indeed express its own truth-concept.

A salient feature of contemporary philosophical logic is the great interest in so-called ‘free logics’, logics admitting non-denoting terms without paraphrase. Proponents of such logics have generally followed one of two approaches, each of which was considered and rejected by Russell in ‘On Denoting’. The first, suggested by Meinong, requires the introduction of possible but non-existent objects as ‘references’ for non-denoting terms. This approach has been by far the more popular among contemporary free logicians, perhaps because many of them came to free logic by way of modal logic.1 The second approach was first suggested by Frege2 and later developed at length by Strawson.3 Roughly put, it characterizes sentences containing non-denoting terms as truth-valueless, i.e. as neither true nor false, while at the same time insisting that such sentences are meaningful and express (truth-valueless) propositions.