Differences In IQ Research Articles

Characteristics of Older Autistic Adults: a Systematic Review of Literature

Autism is a neurodevelopmental condition that affects individuals across their lifetime, though the effects of ageing in older adulthood are poorly understood to date. This systematic review assessed six characteristics in older autistic adults (cognitive functioning, co-occurring difficulties, autism symptom severity, social integration, adaptive functioning, language processing). A total of 41 studies met inclusion criteria, 16 of which included autistic adults with intellectual disability, and three were longitudinal in nature. Findings show differing effects of ageing across the six domains. Factors contributing to discrepancies such as age and IQ differences, methodology and healthy survivor effect are discussed. The need for more longitudinal studies to investigate changes across developmental stages alongside other limitations, future directions and clinical implications are discussed.

Emotion Recognition from Realistic Dynamic Emotional Expressions Cohere with Established Emotion Recognition Tests: A Proof-of-Concept Validation of the Emotional Accuracy Test.

Individual differences in understanding other people’s emotions have typically been studied with recognition tests using prototypical emotional expressions. These tests have been criticized for the use of posed, prototypical displays, raising the question of whether such tests tell us anything about the ability to understand spontaneous, non-prototypical emotional expressions. Here, we employ the Emotional Accuracy Test (EAT), which uses natural emotional expressions and defines the recognition as the match between the emotion ratings of a target and a perceiver. In two preregistered studies (Ntotal = 231), we compared the performance on the EAT with two well-established tests of emotion recognition ability: the Geneva Emotion Recognition Test (GERT) and the Reading the Mind in the Eyes Test (RMET). We found significant overlap (r > 0.20) between individuals’ performance in recognizing spontaneous emotions in naturalistic settings (EAT) and posed (or enacted) non-verbal measures of emotion recognition (GERT, RMET), even when controlling for individual differences in verbal IQ. On average, however, participants reported enjoying the EAT more than the other tasks. Thus, the current research provides a proof-of-concept validation of the EAT as a useful measure for testing the understanding of others’ emotions, a crucial feature of emotional intelligence. Further, our findings indicate that emotion recognition tests using prototypical expressions are valid proxies for measuring the understanding of others’ emotions in more realistic everyday contexts.

Limited Internal Comparability of General Intelligence Composites: Impact on External Validity, Possible Predictors, and Practical Remedies.

Research on comparability of general intelligence composites (GICs) is scarce and has focused exclusively on comparing GICs from different test batteries, revealing limited individual-level comparability. We add to these findings, investigating the group- and individual-level comparability of different GICs within test batteries (i.e., internal score comparability), thereby minimizing transient error and ruling out between-battery variance completely. We (a) determined the magnitude of intraindividual IQ differences, (b) investigated their impact on external validity, (c) explored possible predictors for these differences, and (d) examined ways to deal with incomparability. Results are based on the standardization samples of three intelligence test batteries, spanning from early childhood to late adulthood. Despite high group-level comparability, individual-level comparability was often unsatisfactory, especially toward the tails of the IQ distribution. This limited comparability has consequences for external validity, as GICs were differentially related to and often less predictive for school grades for individuals with high IQ differences. Of several predictors, only IQ level and age were systematically related to comparability. Consequently, findings challenge the use of overall internal consistencies for confidence intervals and suggest using confidence intervals based on test–retest reliabilities or age- and IQ-specific internal consistencies for clinical interpretation. Implications for test construction and application are discussed.

Penanaman Nilai-Nilai Agama Islam Melalui Kegiatan Ekstrakurikuler Pramuka Di SMP PGRI Jogoroto – Jombang

Scout education in Indonesia is an important aspect of national education and is part of the history of Indonesia's struggle. In its development, scouting education has begun to be less attractive and is considered a monotonous activity and what is learned is only that. Whereas behind the simplicity of scouting education, scouting activities can be observed seriously and will develop all the potential that has been bestowed by Allah to humans related to Islamic religious values ??contained in the basic principles of scouting. The purpose of this research is to describe the cultivation of Islamic religious values ??through scout extracurricular activities at SMP PGRI Jogoroto. Supporting and inhibiting factors for planting Islamic religious values ??through scout extracurricular activities at SMP PGRI Jogoroto. This type of research includes field research using a qualitative approach. Data collection techniques through interviews, observation, and documentation. Data analysis using data reduction, data display and verification. Furthermore, the data validity test technique is through participation extension, observation persistence, and triangulation. The result of this research is the method of planting Islamic religious values, namely the method of advising, the method of letting go, and the method of modeling. The material for planting Islamic religious values ??is the values ??of faith and moral values. Supporting factors: psychological factors in the form of student motivation, social environmental factors, learning approach factors. Inhibiting factors, namely the lack of parental education for children, a less supportive environment, and differences in student IQ.

Characterizing neuroanatomic heterogeneity in people with and without ADHD based on subcortical brain volumes.

BackgroundAttention‐deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder. Neuroanatomic heterogeneity limits our understanding of ADHD’s etiology. This study aimed to parse heterogeneity of ADHD and to determine whether patient subgroups could be discerned based on subcortical brain volumes.MethodsUsing the large ENIGMA‐ADHD Working Group dataset, four subsamples of 993 boys with and without ADHD and to subsamples of 653 adult men, 400 girls, and 447 women were included in analyses. We applied exploratory factor analysis (EFA) to seven subcortical volumes in order to constrain the complexity of the input variables and ensure more stable clustering results. Factor scores derived from the EFA were used to build networks. A community detection (CD) algorithm clustered participants into subgroups based on the networks.ResultsExploratory factor analysis revealed three factors (basal ganglia, limbic system, and thalamus) in boys and men with and without ADHD. Factor structures for girls and women differed from those in males. Given sample size considerations, we concentrated subsequent analyses on males. Male participants could be separated into four communities, of which one was absent in healthy men. Significant case–control differences of subcortical volumes were observed within communities in boys, often with stronger effect sizes compared to the entire sample. As in the entire sample, none were observed in men. Affected men in two of the communities presented comorbidities more frequently than those in other communities. There were no significant differences in ADHD symptom severity, IQ, and medication use between communities in either boys or men.ConclusionsOur results indicate that neuroanatomic heterogeneity in subcortical volumes exists, irrespective of ADHD diagnosis. Effect sizes of case–control differences appear more pronounced at least in some of the subgroups.

The gap between IQ and adaptive functioning in autism spectrum disorder: Disentangling diagnostic and sex differences.

Adaptive functioning refers to skills that are vital to success in day-to-day life, including daily living (e.g. grocery shopping, food preparation, transportation use), communication (e.g. verbal expression of needs), and socialization skills (e.g. interpersonal skills, including expressing and recognizing emotions, and understanding turn-taking in conversation). Among autistic individuals without intellectual disability, adaptive functioning is not commensurate with intellectual ability (IQ), and instead a gap exists between these individuals' intellectual ability and their adaptive skills. Further, these autistic individuals show a widening of this gap with increasing age. Existing studies of the gap between IQ and adaptive functioning have studied predominantly male samples. Thus, we do not know if the gap also exists in autistic females. We therefore looked at adaptive functioning and the gap between IQ and adaptive functioning in a large sample of autistic girls and boys without intellectual disability. To disentangle effects of group (autistic vs typically developing) from effects of sex (girls vs boys), we compared autistic girls and boys to one another as well as to their same-sex typically developing peers. Analyses took into consideration differences in IQ between autistic and typically developing youth. We found autistic girls, like autistic boys, show lower adaptive functioning than their same-sex typically developing peers. Results underscore the need to evaluate adaptive functioning in autistic individuals without intellectual disability and to provide necessary supports. The large gap between intellectual ability and socialization skills, in particular, may be of critical importance in improving our understanding of outcomes and mental health difficulties among autistic females.

No support for the hereditarian hypothesis of the Black-White achievement gap using polygenic scores and tests for divergent selection.

Debate about the cause of IQ score gaps between Black and White populations has persisted within genetics, anthropology, and psychology. Recently, authors claimed polygenic scores provide evidence that a significant portion of differences in cognitive performance between Black and White populations are caused by genetic differences due to natural selection, the "hereditarian hypothesis." This study aims to show conceptual and methodological flaws of past studies supporting the hereditarian hypothesis. Polygenic scores for educational attainment were constructed for African and European samples of the 1000 Genomes Project. Evidence for selection was evaluated using an excess variance test. Education associated variants were further evaluated for signals of selection by testing for excess genetic differentiation (Fst ). Expected mean difference in IQ for populations was calculated under a neutral evolutionary scenario and contrasted to hereditarian claims. Tests for selection using polygenic scores failed to find evidence of natural selection when the less biased within-family GWAS effect sizes were used. Tests for selection using Fst values did not find evidence of natural selection. Expected mean difference in IQ was substantially smaller than postulated by hereditarians, even under unrealistic assumptions that overestimate genetic contribution. Given these results, hereditarian claims are not supported in the least. Cognitive performance does not appear to have been under diversifying selection in Europeans and Africans. In the absence of diversifying selection, the best case estimate for genetic contributions to group differences in cognitive performance is substantially smaller than hereditarians claim and is consistent with genetic differences contributing little to the Black-White gap.

Protocol for assessing whether cognition of preterm infants

IntroductionDocosahexaenoic acid (DHA) is an omega-3 (n-3) fatty acid that accumulates into neural tissue during the last trimester of pregnancy, as the fetal brain is undergoing a growth spurt. Infants...

Cognitive Inflexibility in OCD and Related Disorders.

Cognitive inflexibility is suggested by the hallmark symptoms of obsessive-compulsive disorder (OCD), namely the occurrence of repetitive thoughts and/or behaviours that persist despite being functionally impairing and egodystonic to the individual. As well as being implied by the top-level symptoms, cognitive inflexibility in OCD, and some related conditions, has also been objectively quantified in case-control studies using computerised cognitive tasks. This chapter begins by considering the objective measurement of different aspects of cognitive flexibility using neuropsychological paradigms, with a focus on neural and neurochemical substrates. It moves on to conduct a systematic review and meta-analysis of findings from a widely deployed flexibility task: the Intra-Dimensional/Extra-Dimensional Set-Shift Task (IDED). By pooling data from 11 studies (335 OCD patients and 311 controls), we show that Extra-Dimensional (ED) shift deficits are a robust and reproducible finding (effect size medium-large) in OCD across the literature, and that this deficit is not attributable to group differences in age or IQ. The OCD ED deficit is then discussed in terms of dysfunction of fronto-striatal pathways (as exemplified, for example, by functional connectivity data), and the putative role of different neurotransmitters. We consider evidence that impaired ED shifting constitutes a candidate vulnerability marker (or 'endophenotype') for OCD. Theavailable literature is then surveyed as to ED findings in other obsessive-compulsive (OC) related disorders (e.g. hoarding, body-dysmorphic disorder, and trichotillomania), as well as in non-OC disorders (schizophrenia and anxiety symptoms in general). Lastly, we consider more recent, emerging developments in the quantification of compulsivity using cognitive tasks and questionnaires, as well as key directions for future research, including the need to refine compulsivity and its composite cognitive processes.

Regional and Sex Differences on the Standard Progressive Matrices in the Kingdom of Saudi Arabia

This study examines the interaction between gender and region in Saudi Arabia on performance in the Standard Progressive Matrices (SPM), a test of non-verbal reasoning. The results of two administrations of the SPM in Saudi Arabia are compared for children between the ages of 8 and 12 years. The first sample included 1,273 school children in this age range, tested in the Makkah region in 2010. The second included 2,385 school children in Riyadh in 2016. There was no statistically significant IQ difference between the two samples. However, females scored significantly higher in Riyadh than in Makkah while males scored significantly higher in Makkah. These differences became more pronounced with age. Keywords: Saudi Arabia, Intelligence, Regional differences, Sex differences

Commentary on Fuerst et al: Do Human Populations Differ in Their Mental Characteristics?

Human populations may differ genetically not only in their anatomy but also in their mental characteristics. Our species is not too young for such differentiation. In fact, human genetic evolution has proceeded faster over the past 10,000 years than over the previous million. With the rise of farming, and social complexity, humans were no longer adapting solely to a limited range of natural environments. They were adapting to an ever-widening range of cultural environments, each of which imposed its demands on mind and body. Thus, mental characteristics do not have the same adaptive value in all environments, and differences in adaptive value will lead, over time, to genetic differences. Are the latter large enough to explain IQ differences between human populations? That question has led to studies of people who are ancestrally diverse but raised in the same environment, such as transracial adoptees. Unfortunately, the environment can never be fully equalized. We should measure genetic differences directly, and a promising step in that direction has come with research to identify alleles associated with educational attainment. There is no need to identify all of them, just a large enough sample. These “witnesses” can then be questioned to determine the strength and direction of natural selection, and its consequences. Also promising is the study of IQ and ancestry in ethnically mixed groups. This research instrument is not without problems. Large continental populations often have high-achieving minorities who may contribute disproportionately to the founding of new groups or to admixture with old ones. In addition, natural selection can alter the distribution of alleles within a new group, even after a few generations. Keywords: Ashkenazi Jews, Cognitive ability, Educational attainment, Gene-culture coevolution, IQ, Parsis, Polygenic score

A Systematic Literature Review of the Burden of Central Nervous System Complications for Patients with Sickle Cell Disease

INTRODUCTION: Sickle cell disease (SCD), a complex genetic blood disorder involving multicellular interactions between blood and endothelial cells, is often accompanied by central nervous system (CNS) complications. Effects range from silent cerebral infarct (SCI) to abnormal blood flow, and consequent overt stroke. This study assessed the humanistic and economic burden associated with CNS complications in patients with SCD and identified patient-reported outcome (PRO) instruments for future research. METHODS: MEDLINE, Embase, Cochrane CENTRAL/CDSR and 11 congresses were searched to identify English language studies published from January 2000 to May 2020 and screened with predefined criteria by two independent researchers. Clinical trials (CT) or observational studies assessing humanistic burden, economic burden, or instruments used to measure burden in patients with SCD and CNS complications (N≥15) were included. Humanistic burden was broadly defined to include quality of life (QoL), symptoms and function. RESULTS: Of the 3194 articles identified, 34 were included. Study designs were 29% retrospective observational (10/34), 29% cross-sectional (10), 26% prospective (9), 9% randomized CT (3), and 6% systematic reviews (2). Study size varied widely (16-4,485 patients with SCD and CNS complications). 77% (26) focused on pediatric patients. Separately, 77% (26) were in a US setting. Overt stroke (12), stroke and SCI (11), or SCI only (7) were the most frequently described CNS complications. Twenty-five studies reported on humanistic burden, 18 of which measured cognitive function using the Wechsler Intelligence Scales. A significant decrease was reported in full scale (FS) (stroke vs. no stroke: 73.5 vs. 84.7; P=.04), verbal (abnormal vs. normal MRI: 74.1 vs. 84.6; P=.02), and performance IQ (stroke vs. no stroke: 69.5 vs. 81.5; P=.02) for patients with overt strokes or SCI compared to non-stroke SCD controls. Greater impairment was reported for overt stroke compared with SCI (multivariate meta-analysis of mean IQ difference: -10.3; P=.0013). In addition to stroke/SCI, socio-environmental factors (i.e., family income level, lack of college education) were significantly associated with a decrease in IQ (P=.005 and P=.023, respectively). Five studies assessed motor function, reporting significantly impaired function for patients with stroke compared to non-stroke SCD controls (Purdue Pegboard both hands: 7.5 vs. 10.1; P=.0001). Among children with SCD who had experienced their first stroke, those receiving hydroxyurea (HU) for prevention of recurrent stroke had significantly less moderate to severe motor disability (physician assessed) than children not receiving HU (23.1 vs. 88.9%; P<.001). Nine studies reported economic outcomes related to healthcare resource use (HCRU) (8) and direct costs (5). HCRU and cost to manage CNS complications are high, with a median LOS of 5 days (IQR 3-9) and median hospitalization charges of $18,956 (2012 USD) for patients with SCD and stroke. Treatment costs were also substantial in patients with SCI, with annual transfusion plus chelation costs ranging between $18,149 and $67,361/year (2016 USD). No studies reported indirect costs. While many studies used clinician-administered performance outcome (PerfO) measures such as the Wechsler Scales, only 1 study employed a PRO instrument: the Children's Depression Index. In addition to the Wechsler Scales, PerfO measures of cognitive function included the Woodcock-Johnson Psychoeducational Battery (6 studies), Children's Memory Scale (4), and California Verbal Learning Test for Children (4). CONCLUSIONS: This systematic review found that SCD patients with CNS complications often experience diminished cognitive/motor function and incur substantial costs. In particular, the mean FSIQ for SCD patients with stroke and SCI was reported to be 'extremely low' to 'low' (65.9 to 83.6) and 'low' to 'average' (77.2 to 95.9), respectively across studies. The Wechsler Scales were the most commonly used PerfO measure of cognitive function, while use of disease-specific PRO instruments was extremely limited. Given that the majority of published data focuses on children, future research is needed to evaluate the burden of disease for SCD adults with CNS complications, and to assess patient perspectives and QoL to better quantify aspects of burden beyond cognitive performance. Disclosures Lee: Novartis Pharmaceuticals Corporation: Current Employment. Nellesen:Analysis Group, Inc.: Consultancy. Lucas:Analysis Group, Inc.: Consultancy. Paulose:Novartis Pharma AG: Current Employment.

A-056 WISC-V Profiles in Children with Congenital Heart Disease: Is the WISC-V Sensitive to Cognitive Impairment in CHD?

Abstract Objective Prior research on intellectual development in children with congenital heart disease (CHD) yielded inconsistent findings. No study has yet examined the Wechsler Intelligence Scale for Children—Fifth Edition (WISC-V). Given its revised factor structure, it is unknown if the WISC-V performs similarly to prior versions in children with CHD. Methods Twenty children (6-13 years) with CHD received the WISC-V; children with co-morbid neurological illness (i.e., stroke, epilepsy) were excluded. Five children underwent the Fontan procedure. Means, standard deviations, and percent impaired (< 5th percentile) were calculated for composites. Effect size estimates compared children with and without the Fontan procedure. Results Mean age was 10.3 (SD = 2.5; 30% male). The mean Full Scale IQ (FSIQ) was 77.8 (SD = 13.7, range = 46-108). No sex difference in age or IQ were observed. The Visual Spatial Index was the lowest composite (VSI; Mean = 78.7, SD = 18.0), followed by the Fluid Reasoning Index (FRI; Mean = 82.0, SD = 15.6), Working Memory Index (WMI; Mean = 82.4, SD = 16.0), Verbal Comprehension Index (VCI; Mean = 84.80, SD = 15.29), and Processing Speed Index (PSI; Mean = 85.6, SD = 14.6). The FRI was most frequently impaired (50% of sample), followed by WMI (40%), VSI (35%), and VCI/PSI (20%). Although children who underwent the Fontan procedure did not differ in FSIQ (Cohen’s d = .06, negligible effect size), they performed more poorly on the PSI (Cohen’s d = .87, large effect size). Conclusions The WISC-V detects deficits in visual perceptual abilities commonly seen in CHD. However, FSIQ for our sample was lower than previously reported. Children with a history of Fontan procedure may show slower processing speed.

ADHD subtypes: Do they hold beyond core symptoms? A multilevel testing of an additive model

Attention Deficit Hyperactivity Disorder (ADHD) is characterized as a behavioral syndrome with core symptoms of inattention and/or hyperactivity/impulsivity that constitute, according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), predominantly Inattentive and Hyperactive-Impulsive and a combined (additive) presentation that fulfills both criteria. The question remains if the pathophysiological background of both factors is also separate at levels of investigation beyond core symptoms. This would allow a clearer understanding and a more focused treatment approach even with tools derived from these levels. Hence, we assumed that an implicit additive diagnostic model also holds at the levels of associated psychopathology, neuropsychological performance and brain oscillations. We investigated this hypothesis using data of 61 boys (7–12 years old) with ADHD and 43 typically developing children. There were no significant differences in age and IQ between groups. Children were examined with Child Behavior Checklist (CBCL), the Integrated Visual and Auditory Test (IVA), and brain oscillations during eyes closed resting state. Inattention characteristics were associated with more pronounced internalizing problems, lower attention, and vigilance during IVA performance and at the Electroencephalography level with elevated Theta and diminished Beta power during eyes closed rest. In contrast, hyperactivity/impulsivity characteristics led to general psychopathology problems and showed at the neuropsychological level faster response speed and deficits in cognitive control and performance consistency, but were on the electroencephalography level without any deficits in EEG power. Considering differences in behavioral, neuropsychology, and electroencephalography levels in each subtype, separate clinical approaches should be recommended for them and an additive model for their combination.

Children’s performance on Raven’s Coloured progressive matrices in Portugal: The Flynn effect

The goal of this study was to examine how IQ changes (the Flynn effect) among school-aged children in Portugal behaved over a period of 25 years (1991, 2008 and 2016) that registered major economic transformations in the country. The country's initial move to prosperity was followed by a recent move into recession, which might affect IQ gains. Changes in IQ by level of intellectual ability were also inspected. Children's scores on Raven's Coloured Progressive Matrices in Portugal were compared between the years 1991, 2008 and 2016. Differences in IQs were calculated according to Flynn's (1987) procedures. In addition, percentile distributions of children's scores in the period of economic growth (between 1991 and 2008) were compared for inspection of IQ changes across levels of intellectual ability. Results showed an IQ gain of 2.6 points per decade from 1991 to 2008, followed by a smaller increase (of 1.7 points per decade) from 2008 to 2016, with negative gains observed for seven-, eight- and 10-year-old children. The gains in IQ from 1991 to 2008 have occurred mainly for lower levels of intellectual ability. IQ relative gains accompanied the country's economic fluctuations, and children in lower levels of intellectual ability seemed to have benefitted the most from the economic growth. The trends in the country are suggestive of the influence of economic fluctuations on family dynamics, which, although moderated by education, have consequences for children's cognitive development.

Newborn Screening TSH Values Less Than 15 mIU/L Are Not Associated With Long-term Hypothyroidism or Cognitive Impairment.

It is unclear whether newborns with mild thyrotropin elevation (mTSHe) are at risk of neurocognitive impairment. We assessed whether mTSHe at birth persists during childhood and compared neurocognitive functioning to siblings. This study encompassed children born in the Auckland region (New Zealand) with a newborn screen TSH level of 8 to 14 mIU/L blood, age 6.9 to 12.6 years at assessment, and their siblings. Thyroid function tests (serum TSH and free thyroxine) and neurocognitive assessments were performed, including IQ via the Wechsler Intelligence Scale for Children, fourth edition. Ninety-six mTSHe individuals were studied, including 67 children recruited with 75 sibling controls. Mean mTSHe newborn TSH level was 10.1 mIU/L blood and 2.4 mIU/L at assessment (range, 0.8-7.0 mIU/L, serum). Although higher newborn TSH levels in the mTSHe group correlated with lower full-scale IQ scores (r = 0.25; P = .040), they were not associated with the magnitude of the IQ difference within sibling pairs (P = .56). Cognitive scores were similar for mTSHe and controls (full-scale IQ 107 vs 109; P = .36), with a minor isolated difference in motor coordination scores. Our data do not suggest long-term negative effects of neonatal mild TSH elevation. TSH elevation below the screen threshold appears largely transient, and midchildhood neurocognitive performance of these children was similar to their siblings. We propose that associations between neonatal mild TSH elevation and IQ are due to familial confounders. We caution against the practice of reducing screening CH cutoffs to levels at which the diagnosis may not offer long-term benefit for those detected.

The Relationship Between Word Learning and Executive Function in Preschoolers With and Without Developmental Language Disorder.

Purpose The purpose of this study was to examine the relationship between executive functioning and word learning among preschoolers with and without developmental language disorder (DLD). Method Forty-one preschool-age children with DLD were matched to typically developing children on age and sex. Participants were exposed to 10 novel pseudowords, half of which referred to familiar objects and half of which referred to unfamiliar objects. Their ability to produce, recognize, and comprehend the novel words was tested, and they completed executive function tasks measuring sustained selective attention, short-term memory, working memory, inhibition, and shifting. Results Preschoolers with DLD performed worse compared to typically developing peers on all measures of executive function and novel word learning. Both groups showed a relative weakness in producing pseudowords that corresponded with familiar objects versus pseudowords for unknown objects. Executive function accounted for statistically significant variance in word learning beyond group membership, with inhibition as a significant predictor of all word learning outcomes and short-term memory as a significant predictor of novel word comprehension. Executive function explained significant variance in novel word production and recognition even after accounting for variance explained by group differences in IQ and receptive vocabulary. Conclusion Findings replicate previous research reporting deficits in word learning and executive function in children with DLD, indicate that preschoolers are disadvantaged in learning new words for familiar objects, and support a relationship between executive function and word learning for children with and without DLD. Future research should examine the directionality of the relationship between these variables.

Autism Spectrum Disorder and Schizophrenia Are Better Differentiated by Positive Symptoms Than Negative Symptoms.

Autism spectrum disorder (ASD) and schizophrenia (SZ) are heterogenous neurodevelopmental disorders that overlap in symptom presentation. The purpose of this study was to specify overlapping symptom domains and to identify symptoms that can reliably differentiate adults with ASD (n = 53), SZ (n = 39), and typical development (TD; n = 40). All participants regardless of diagnosis were administered gold-standard diagnostic assessments of ASD and SZ characteristics including the Autism Diagnostic Observation Schedule (ADOS-2) and the Positive and Negative Syndrome Scale (PANSS). Sensitivity and specificity of the ADOS were assessed using diagnostic cut-off scores. The degree of symptom overlap on these measures between participant groups was analyzed using Analyses of Variance (ANOVAs), Receiver Operating Characteristic (ROC) Curves, and Analyses of Covariance (ANCOVAs) to control for group differences in IQ and sex distributions. The ADOS reliably discriminated ASD and TD adults, but there was a high rate of “false positives” in SZ patients who did not meet the DSM-5 criteria for ASD. To identify the reasons for low specificity in the SZ sample, we categorized ASD and SZ symptoms into ‘positive’ (presence of atypical behaviors) and ‘negative’ (absence of typical behaviors) symptoms. ASD and SZ groups overlapped on negative symptoms largely related to the absence of typical social and communicative behaviors, whereas disorder-specific positive symptoms differentiated ASD and SZ. For example, those with ASD scored higher on restricted and repetitive behaviors and stereotyped language, whereas those with SZ scored higher on psychotic symptoms such as delusions and hallucinations. These results suggest that, when making a differential diagnosis between ASD and SZ, clinicians may benefit from focusing on the presence or absence of positive ASD and SZ symptoms. Standardized measures to classify ASD symptoms into positive and negative symptoms have not yet been developed but represent a potentially viable clinical tool.

The impact of childhood deprivation on adult neuropsychological functioning is associated with ADHD symptom persistence

Institutional deprivation in early childhood is associated with neuropsychological deficits in adolescence. Using 20-year follow-up data from a unique natural experiment - the large-scale adoption of children exposed to extreme deprivation in Romanian institutions in the 1980s -we examined, for the first time, whether such deficits are still present in adulthood and whether they are associated with deprivation-related symptoms of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Adult neuropsychological functioning was assessed across five domains (inhibitory control, emotion recognition, decision-making, prospective memory and IQ) in 70 previously institutionalized adoptees (mean age = 25.3, 50% female) and 22 non-deprived UK adoptees (comparison group, mean age = 24.6, 41% female). ADHD and ASD symptoms were assessed using parent-completed questionnaires. Early institutionalization was associated with impaired performance on all tasks in adulthood. Prospective memory deficits persisted after controlling for IQ. ADHD and ASD symptoms were positively correlated. After controlling for ASD symptoms, ADHD symptoms remained associated with deficits in IQ, prospective memory, proactive inhibition, decision-making quality and emotion recognition. ASD symptoms were not independently associated with neuropsychological deficits when accounting for their overlap with ADHD symptoms. Multiple regression analysis revealed that the link between childhood deprivation and adult ADHD symptoms was statistically explained by deprivation-related differences in adult IQ and prospective memory. These results represent some of the most compelling evidence to date of the enduring power of early, time-limited childhood adversity to impair long-term neuropsychological functioning across the lifespan - effects that are linked specifically to deprivation-related adult ADHD symptoms.

O9.6. SYSTEMATIC REVIEW AND META-ANALYSIS OF THE EFFECTS OF CANNABIS USE IN ADOLESCENCE ON IQ IN LONGITUDINAL STUDIES ACCOUNTING PRE-EXPOSURE BASELINE PERFORMANCE

BackgroundCannabis use in adolescence is a known risk factor for developing schizophrenia. Decline in intellectual functioning is a well-studied phenomenon of schizophrenia. Schizophrenia in its first classification was conceptualized as a dementia - ‘Dementia Praecox’ indicating a dominance of effect of cognitive symptoms on functioning at that time. First episode psychosis patients with histories of cannabis use compared to those without cannabis use have superior cognitive functioning suggesting different disease phenotypes. Our aim was to investigate whether cannabis had an effect on full scale IQ in general population samples to further inform understanding of this disease pathway.MethodsWe developed a search strategy through an iterative approach with a qualified information specialist. We searched three databases: Medline, Embase and PsychInfo. We included conference abstracts and full text publications in English. We contacted authors for additional information in cases where an effect size was not calculable. We included longitudinal studies of non-help-seeking young people in the community with a pre-drug exposure standardized measure of IQ prior to the age of 18 and a comparable measure at subsequent follow up. We defined the case group as individuals with a history of heavy cannabis use (more than 25 lifetime uses, at least weekly use for 6 months and/or meeting criteria for a cannabis use disorder) and the control group as similar young people who had no or very minimal experimental exposure to cannabis (<5 lifetime uses). Two reviewers independently extracted the data and assessed for bias using the Newcastle-Ottawa risk of bias tool. We performed random effects meta-analysis in Stata version 14 given expected heterogeneity in measurement of cannabis use across studies.ResultsWe identified 7 cohort studies detailed in 6 reports including over 650 subjects and 5600 controls. Study designs included twin cohorts, representative cluster sampled community cohorts and birth cohort studies. Range of follow up was between 2 and 23 years. All studies showed relative decline in IQ of which two were statistically significant. Our findings show that cannabis use in youth is associated with modest IQ differences that equate to approximately to a 2-point decrease in young cannabis users. Studies examining twin pairs showed that twins discordant for cannabis use did not have divergent cognitive trajectories, however these analyses were relatively underpowered to find an effect.DiscussionOur findings demonstrate the harmful effects of cannabis use on brain development in young people. These findings are of public health importance and provide further evidence for the detrimental effects of early cannabis use on mental health and cognition.