abstract: There is a robust association between psychosis and cannabis use, but the mechanisms underlying this relation are poorly understood. Because both psychosis and cannabis use have been linked to cardiovascular problems, it is possible that cannabis use exacerbates an underlying vascular vulnerability in individuals prone to psychosis. To investigate microvascular differences in individuals with psychotic symptoms and cannabis use, the current study tested associations between psychotic-like experiences, cannabis use, and retinal vessel diameter in 101 young adults (mean age=19.37 years [SD=1.93]). Retinal venular diameter did not differ between participants with (M=218.08, SD=15.09) and without psychotic-like experiences (M=216.61, SD=16.18) (F(1, 97)=0.01, p=.93) or between cannabis users (M=218.41, SD=14.31) and non-users (M=216.95, SD=16.26) (F(1, 97)=0.37, p=.54). Likewise, mean retinal arteriolar diameter did not differ between participants with (M=157.07, SD=10.96) and without psychotic-like experiences (M=154.88, SD=9.03) (F(1, 97)=0.00, p=.97). However, cannabis users had statistically significantly wider retinal arterioles (M=159.10, SD=9.94) than did non-users (M=154.29, SD=10.20) (F(1, 97)=5.99, p=.016), and this effect was robust to control for covariates. There was no evidence of an interaction between psychotic-like experiences and cannabis use in predicting retinal vessel diameter. These results indicate that cannabis use is associated with microvascular differences in young adulthood. Given current trends toward legalization of recreational cannabis use, future research should explore these differences and their potential consequences for cardiovascular health. / Dissertation/Thesis / Masters Thesis Psychology 2016

While many studies of risk factors for psychosis focus on positive symptoms, such as subthreshold levels of hallucinations and delusions, fewer studies have examined negative symptoms in the early course of the schizophrenia or other psychotic disorders. This relative lack of focus on the role of negative symptoms is problematic, given findings that negative symptoms, such as a loss of motivation and pleasure (MAP), are associated with a more persistent and impairing course of psychosis, and tend to appear earlier in the development of psychotic symptoms. Psychotic disorders, which afflict approximately 3-5% of the population, tend to emerge in late adolescence/early adulthood and are among the most debilitating and costly of mental disorders. The current project explored three areas of negative symptoms in young adults who demonstrated a range of psychotic-like experiences (PLEs). First, a review of the literature pertaining to negative symptoms across the span of psychosis was conducted. Second, we tested whether experiential negative symptoms – specifically MAP deficits – were associated with increases in PLEs, including those that are experienced as distressing (PLEDs). Third, we examined the potential influence of episodic memory performance factors on the relationship between MAP symptoms and PLEs/PLEDs. Collectively, this project highlights the importance of including negative symptoms (i.e., MAP deficits) and/or cognitive performance (i.e., associative/relational learning/memory) outcomes when evaluating people with PLEs/PLEDs to identify those who may be at greater risk for developing a psychotic disorder. / Psychology

Existem evidências de que as manifestações psicóticas não são vivenciadas apenas por pessoas diagnosticadas com transtornos mentais, mas também por pessoas saudáveis da população geral, as denominadas experiências tipo-psicóticas. A Escala de Avaliação das Experiências Psíquicas na Comunidade (CAPE) é um instrumento usado em pesquisas epidemiológicas e foi desenvolvido especificamente para a detecção e avaliação da frequência de experiências tipo-psicóticas na população geral. A CAPE, em sua apresentação original é composta por 42 itens, distribuídos em três dimensões: positiva, negativa e depressiva. O objetivo deste estudo foi verificar as evidências de fidedignidade e validade da CAPE em uma amostra brasileira e investigar a associação de traumas na infância e uso de cannabis com a ocorrência de experiências tipo-psicóticas em indivíduos da população geral. A amostra foi composta por 217 pacientes em primeiro episódio psicótico, 104 irmãos de pacientes psicóticos e 319 controles de base populacional, todos residentes na área de cobertura do Departamento Regional de Saúde do Estado de São Paulo (DRS XIII). Os participantes responderam a instrumentos de avaliação e diagnósticos, incluindo a Entrevista Clínica Estruturada para o DSM IV (SCID), o Questionário sobre Traumas na Infância (CTQ), Questionário de Experiências com Maconha (CEQ), além da CAPE. Os dados clínicos foram analisados por meio do pacote estatístico SPSS e as evidências psicométricas por meio do software AMOS. Após a retirada de nove itens, a CAPE, com 33 itens, mostrou bons índices de ajustamento [CFI = 0,895; GFI = 0,822; PGFI = 0,761; RMSEA = 0,055 p (rmsea <= 0,05) = 0,04] e boa consistência interna (> 0,70) em todos as suas dimensões. Nas análises realizadas apenas com a amostra de base populacional, não foram encontradas diferenças significativas entre as pontuações totais da CAPE-33 e das suas três dimensões quanto a intervalos de idade, estado civil e escolaridade. Mulheres apresentaram pontuações significativamente mais elevadas do que os homens no escore total (p<0,001) e nas dimensões negativa (p < 0,001) e depressiva (p < 0,001). A vivência de traumas na infância (abuso emocional, abuso físico, abuso sexual, negligência emocional, negligência física) associou-se com pontuações mais elevadas no escore total da CAPE (p <0,001) e nas suas três dimensões (positiva p = 0.001, negativa p = 0,004, depressiva p < 0,001). Indivíduos que relataram uso de cannabis alguma vez na vida apresentaram maiores pontuações na dimensão positiva da CAPE-33, em comparação às pessoas que nunca usaram a substância (p = 0,016). A CAPE adaptada para o Brasil (CAPE-33) mostrou bons índices de ajustamento e consistência interna, como encontrado em outras culturas. Presença de trauma precoce e uso de cannabis associaram-se à ocorrência de experiências tipo-psicóticas, à semelhança do que os estudos epidemiológicos mostram para a esquizofrenia. Nossos dados corroboram a abordagem dimensional das psicoses, com frequência e gravidade das manifestações se distribuindo num continnum na população geral. / There is evidence that psychotic manifestation is not experienced only by people diagnosed with mental disorders but also by healthy people in the general population, known as psychotic-like experiences. The Community Assessment Psychic Experiences (CAPE) is an instrument used in epidemiological research and was developed specifically for the detection and evaluation of the frequency of psychotic-like experiences in the general population. The CAPE, in its original submission, is composed of 42 items, distributed in three dimensions: positive, negative and depressive. The objective of this study was to verify the evidence of reliability and validity the CAPE in a brazilian sample and to investigate the association of childhood traumas and cannabis use with the occurrence of psychotic-like experiences in individuals of the general population. The sample consisted of 217 patients in the first psychotic episode, 104 siblings of psychotic patients and 319 population-based controls, all residents in the coverage area of the São Paulo Regional Health Department (DRS XIII). Participants responded to assessment and diagnostic tools, including the Structured Clinical Interview for DSM IV (SCID), the Childhood Trauma Questionnaire (CTQ), the Cannabis Experience Questionnaire (CEQ), and CAPE. Clinical data were analyzed using SPSS statistical package and the psychometric evidence using AMOS software. After the removal of nine items, CAPE, with 33 items, showed good adjustment indices [CFI = 0.895; GFI = 0.822; PGFI = 0.761; RMSEA = 0.055 p (rmsea <= 0.05) = 0.04] and good internal consistency (> 0.70) in all its dimensions. In the analyzes performed only with the population-based sample, no significant differences were found between the CAPE-33 total scores and its three dimensions regarding age, marital status and schooling intervals. Women presented scores significantly higher than men in the total score (p <0.001) and in the negative (p <0.001) and depressive (p <0.001) dimensions. The experience of childhood traumas (emotional abuse, physical abuse, sexual abuse, emotional neglect, physical neglect) was associated with higher scores in the CAPE total score (p <0.001) and its three dimensions (positive p = 0.001, negative p = 0.004, depressive p <0.001). Individuals who reported cannabis use in their lifetime had higher scores in the positive dimension of the CAPE-33 compared to people who had never used the substance (p = 0.016). The CAPE adapted to Brazil (CAPE-33) showed good adjustment indices and internal consistency, as found in other cultures. Presence of early trauma and use of cannabis were associated with the occurrence of psychotic-like experiences, in accordance with what epidemiological studies show for schizophrenia. Our data corroborate the dimensional approach of the psychoses, with frequency and severity of the manifestations being distributed in a continnum in the general population.

Existem evidências de que as manifestações psicóticas não são vivenciadas apenas por pessoas diagnosticadas com transtornos mentais, mas também por pessoas saudáveis da população geral, as denominadas experiências tipo-psicóticas. A Escala de Avaliação das Experiências Psíquicas na Comunidade (CAPE) é um instrumento usado em pesquisas epidemiológicas e foi desenvolvido especificamente para a detecção e avaliação da frequência de experiências tipo-psicóticas na população geral. A CAPE, em sua apresentação original é composta por 42 itens, distribuídos em três dimensões: positiva, negativa e depressiva. O objetivo deste estudo foi verificar as evidências de fidedignidade e validade da CAPE em uma amostra brasileira e investigar a associação de traumas na infância e uso de cannabis com a ocorrência de experiências tipo-psicóticas em indivíduos da população geral. A amostra foi composta por 217 pacientes em primeiro episódio psicótico, 104 irmãos de pacientes psicóticos e 319 controles de base populacional, todos residentes na área de cobertura do Departamento Regional de Saúde do Estado de São Paulo (DRS XIII). Os participantes responderam a instrumentos de avaliação e diagnósticos, incluindo a Entrevista Clínica Estruturada para o DSM IV (SCID), o Questionário sobre Traumas na Infância (CTQ), Questionário de Experiências com Maconha (CEQ), além da CAPE. Os dados clínicos foram analisados por meio do pacote estatístico SPSS e as evidências psicométricas por meio do software AMOS. Após a retirada de nove itens, a CAPE, com 33 itens, mostrou bons índices de ajustamento [CFI = 0,895; GFI = 0,822; PGFI = 0,761; RMSEA = 0,055 p (rmsea <= 0,05) = 0,04] e boa consistência interna (> 0,70) em todos as suas dimensões. Nas análises realizadas apenas com a amostra de base populacional, não foram encontradas diferenças significativas entre as pontuações totais da CAPE-33 e das suas três dimensões quanto a intervalos de idade, estado civil e escolaridade. Mulheres apresentaram pontuações significativamente mais elevadas do que os homens no escore total (p<0,001) e nas dimensões negativa (p < 0,001) e depressiva (p < 0,001). A vivência de traumas na infância (abuso emocional, abuso físico, abuso sexual, negligência emocional, negligência física) associou-se com pontuações mais elevadas no escore total da CAPE (p <0,001) e nas suas três dimensões (positiva p = 0.001, negativa p = 0,004, depressiva p < 0,001). Indivíduos que relataram uso de cannabis alguma vez na vida apresentaram maiores pontuações na dimensão positiva da CAPE-33, em comparação às pessoas que nunca usaram a substância (p = 0,016). A CAPE adaptada para o Brasil (CAPE-33) mostrou bons índices de ajustamento e consistência interna, como encontrado em outras culturas. Presença de trauma precoce e uso de cannabis associaram-se à ocorrência de experiências tipo-psicóticas, à semelhança do que os estudos epidemiológicos mostram para a esquizofrenia. Nossos dados corroboram a abordagem dimensional das psicoses, com frequência e gravidade das manifestações se distribuindo num continnum na população geral. / There is evidence that psychotic manifestation is not experienced only by people diagnosed with mental disorders but also by healthy people in the general population, known as psychotic-like experiences. The Community Assessment Psychic Experiences (CAPE) is an instrument used in epidemiological research and was developed specifically for the detection and evaluation of the frequency of psychotic-like experiences in the general population. The CAPE, in its original submission, is composed of 42 items, distributed in three dimensions: positive, negative and depressive. The objective of this study was to verify the evidence of reliability and validity the CAPE in a brazilian sample and to investigate the association of childhood traumas and cannabis use with the occurrence of psychotic-like experiences in individuals of the general population. The sample consisted of 217 patients in the first psychotic episode, 104 siblings of psychotic patients and 319 population-based controls, all residents in the coverage area of the São Paulo Regional Health Department (DRS XIII). Participants responded to assessment and diagnostic tools, including the Structured Clinical Interview for DSM IV (SCID), the Childhood Trauma Questionnaire (CTQ), the Cannabis Experience Questionnaire (CEQ), and CAPE. Clinical data were analyzed using SPSS statistical package and the psychometric evidence using AMOS software. After the removal of nine items, CAPE, with 33 items, showed good adjustment indices [CFI = 0.895; GFI = 0.822; PGFI = 0.761; RMSEA = 0.055 p (rmsea <= 0.05) = 0.04] and good internal consistency (> 0.70) in all its dimensions. In the analyzes performed only with the population-based sample, no significant differences were found between the CAPE-33 total scores and its three dimensions regarding age, marital status and schooling intervals. Women presented scores significantly higher than men in the total score (p <0.001) and in the negative (p <0.001) and depressive (p <0.001) dimensions. The experience of childhood traumas (emotional abuse, physical abuse, sexual abuse, emotional neglect, physical neglect) was associated with higher scores in the CAPE total score (p <0.001) and its three dimensions (positive p = 0.001, negative p = 0.004, depressive p <0.001). Individuals who reported cannabis use in their lifetime had higher scores in the positive dimension of the CAPE-33 compared to people who had never used the substance (p = 0.016). The CAPE adapted to Brazil (CAPE-33) showed good adjustment indices and internal consistency, as found in other cultures. Presence of early trauma and use of cannabis were associated with the occurrence of psychotic-like experiences, in accordance with what epidemiological studies show for schizophrenia. Our data corroborate the dimensional approach of the psychoses, with frequency and severity of the manifestations being distributed in a continnum in the general population.

Background: Apart from individuals with clinical psychosis, community surveys have shown that many otherwise-well individuals endorse items designed to identify psychosis. The clinical relevance of psychotic-like experiences (PLE) in individuals who are not psychotic is not clear. This thesis aimed to examine the prevalence, demographic and psychosocial correlates and antecedents of PLE in the Australian community. Method: Data from three population-based studies was examined. The Australian National Survey of Mental Health and Wellbeing interviewed 10,641 individuals living in private dwellings in Australia. We examined the impact of selected demographic variables on endorsement of psychosis screen and probe items from the Composite International Diagnostic Interview (CIDI). We also examined the effect of exposure to traumatic events (with and without Post Traumatic Stress Disorder (PTSD)) on the endorsement of CIDI psychosis items. The youth component of the Australian National Survey of Mental Health and Wellbeing collected demographic and clinical data on a nationally representative sample of 1261 adolescents aged 13-17 years. The prevalence of hallucination endorsement on the Youth Self Report (YSR) in Australian adolescents was examined. The association between hallucination endorsement, demographic variables (sex, age, urbanicity and family composition) and clinical variables (self-reported depression, marijuana and alcohol use, DSM IV diagnoses, emotional/ behavioral problems as reported by the parent on the Child Behaviour Check List (CBCL)) were examined. The Mater- University of Queensland Study of Pregnancy (MUSP) is a prospective longitudinal birth cohort study of 7223 mothers and their offspring who received antenatal care between 1981 and 1984. Psychotic-like experiences were assessed in the offspring at the 21 year follow-up using the Peters Delusional Inventory (PDI) and the CIDI. We examined the prevalence of PLEs, and examined the effect of age (the age range at the 21 year follow-up was 18 to 23 years) and sex on PLE. A second study examined the emotional and behavioural antecedents of PLE at 21 years as measured by the CBCL at five and 14 years and the YSR at 14 years. Results: An estimated 11.7% of Australian adults endorsed at least one psychosisscreening item. Higher endorsement was associated with younger age, migrants from non- English speaking backgrounds, not being married, unemployment, living in an urban region and lowest socioeconomic levels. Exposure to any traumatic event was associated with increased endorsement of PLE (Rate Ratio =2.68; 95% CI 2.18, 3.30). A diagnosis of PTSD further increased endorsement of PLE (Rate Ratio =9.24; 95% CI 6.95, 12.27). Hallucinations were reported by 8.4% of Australian adolescents. Those living in blended or sole parent families were more likely to report hallucinations than those living with both biological parents (OR 3.27; 95% CI 1.93, 5.54; OR 2.60; 95% CI 1.63, 4.13 respectively). Hallucinations were more prevalent in adolescents who had high CBCL scores or elevated depression symptoms (OR 3.30; 95% CI 2.10, 5.20; OR 5.02; 95% CI 3.38, 7.45 respectively). Hallucinations were more prevalent in those adolescents who had smoked cannabis more than twice in the month prior to the survey (OR 3.27; 95% CI 1.76, 6.08). In the 21 year follow-up of the MUSP study, older age (18-20 compared to 21-23 years) was significantly associated with a reduction of CIDI delusions (OR 0.66, 95% CI 0.48, 0.92) and PDI total scores (OR=0.68, 95% CI 0.55, 0.83). Women were significantly more likely to endorse items related to hallucinations (OR=1.49, 95% CI 1.14, 1.95) but not delusions. High CBCL scores at 5 and 14 years predicted high total PDI scores; Those in the highest quartile of YSR scores at 14 years were nearly four times more likely to have high levels of psychotic-like experiences at age 21 (OR=3.71, 95% CI 2.92, 4.71). Adolescent onset psychopathology and continuous psychopathology through both childhood and adolescence strongly predict PLE at age 21. Conclusions: Psychotic-like experiences are relatively common in population surveys of Australian adults and adolescents. In adults, the demographic correlates of PLE are similar to those of schizophrenia. There is a strong association between PLE and exposure to trauma. The correlates of PLE in adolescents are different to those of adults. The reduction in prevalence of delusions between late adolescence and young adulthood is coincident with normal neurophysiological changes in the frontal lobes, suggesting hypotheses suitable for future research. The association between marijuana use and hallucinations in adolescents is further evidence of the potential harm caused by use of cannabis. The onset or persistence of emotional distress during adolescence is associated with an increased risk of PLE in adulthood. These findings are relevant to both clinical practice and future research. Psychotic symptoms create diagnostic uncertainty. There is potential for patients with anxiety (PTSD) or mood disorders to be incorrectly diagnosed with a psychotic illness and receive inappropriate management. Equally, there is a risk that subjects who have an emerging psychotic disorder and comorbid anxiety or depression or have had exposure to traumatic events may have treatment of their psychosis delayed as psychotic symptoms are incorrectly ascribed to a syndrome other than psychosis. Clinicians need to be aware of this diagnostic tension so that accurate assessments and appropriate treatments can be initiated at the earliest possible opportunity. The resolution of childhood emotional distress prior to adolescence appears to reduce the risk of PLE and possibly psychosis in adults. Strategies targeting emotionally distressed children may offer opportunities for psychosis prevention. Further research is required to explore the relationship between PLE and vulnerability to psychosis and other mental health problems. It remains unclear if PLE are reliable endophenotypes for schizophrenia. If this is the case, examining genetic and environmental risk factors for onset and persistence of PLE, and the neuroimaging changes that occur as individuals with PLE convert to psychosis will provide important new clues to our understanding of the aetiopathogenesis of psychosis.

Schizotypy, a complex construct linked to schizophrenia-related traits, encompasses positive, negative, and disorganized symptoms. This study offers a review of the concept of schizotypy, including its historical evolution, tracing it from Bleuler's early mention in 1911 to Meehl's continuum model. Embracing a dimensional perspective, this research underscores the interplay of biological, psychological, and social factors in understanding schizotypy. Deficits in sustained attention and working memory within schizotypy remain underexplored, with prior studies yielding inconsistent results. Adaptive functioning deficits in individuals with schizotypy are also inadequately understood. Examining a college student population, this investigation utilized scores on the Schizotypal Personality Questionnaire – Brief Revised (SPQ-BR) to psychometrically define schizotypy, and it used the Community Assessment of Psychic Experiences (CAPE-42), World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), Continuous Performance Task (CPT-IP) and Visuospatial n-Back Task to assess the hypotheses. This was accomplished by comparing 60 individuals in the schizotypy group with 60 carefully matched controls. Contrary to expectations, those with schizotypy exhibited superior performance on sustained attention and visuospatial working memory tasks compared to controls, challenging the established literature, and warranting replication. The study addresses methodological gaps by using carefully matched control groups and employing innovative online cognitive tests. Despite observed cognitive strengths in performance, a paradox emerged as schizotypal individuals self-reported lower cognitive functioning, suggesting the need to focus on metacognition in schizotypy in future studies. This study underscores the need for a comprehensive systematic assessment of emerging young adult populations to understand their current psychological functioning relative to other community samples. The association between schizotypy, positive psychotic-like experiences, and increased self-reported disability suggests a need for the development of preventive interventions. The Hierarchical Taxonomy of Psychopathology (HITOP) is suggested as a promising assessment system for schizophrenia spectrum disorders in college students.

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