Julie Walsh-messinger | University of Dayton (original) (raw)

Papers by Julie Walsh-messinger

Research paper thumbnail of telomere%20length%20paper%20%20mgg371

Research paper thumbnail of Diminished range of emotion responses to negative odorants in schizophrenia

Research paper thumbnail of Rare variants in the neurotrophin signaling pathway implicated in schizophrenia risk

Schizophrenia Research, 2015

Multiple lines of evidence corroborate impaired signaling pathways as relevant to the underpinnin... more Multiple lines of evidence corroborate impaired signaling pathways as relevant to the underpinnings of schizophrenia. There has been an interest in neurotrophins, since they are crucial mediators of neurodevelopment and in synaptic connectivity in the adult brain. Neurotrophins and their receptors demonstrate aberrant expression patterns in cortical areas for schizophrenia cases in comparison to control subjects. There is little known about the contribution of neurotrophin genes in psychiatric disorders. To begin to address this issue, we conducted high-coverage targeted exome capture in a subset of neurotrophin genes in 48 comprehensively characterized cases with schizophrenia-related psychosis. We herein report rare missense polymorphisms and novel missense mutations in neurotrophin receptor signaling pathway genes. Furthermore, we observed that several genes have a higher propensity to harbor missense coding variants than others. Based on this initial analysis we suggest that rare variants and missense mutations in neurotrophin genes might represent genetic contributions involved across psychiatric disorders.

Research paper thumbnail of Following in the footsteps of Kraepelin and Bleuler: Evidence for separate dimensions of affective and volitional deficits in DSM-V schizophrenia

Research paper thumbnail of Validation of the Curious Experiences Survey (CES) in an urban minority population

Research paper thumbnail of Diagnosis of Psychoses

Research paper thumbnail of Parental age effects on odor sensitivity in healthy subjects and schizophrenia patients

American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 2015

A schizophrenia phenotype for paternal and maternal age effects on illness risk could benefit eti... more A schizophrenia phenotype for paternal and maternal age effects on illness risk could benefit etiological research. As odor sensitivity is associated with variability in symptoms and cognition in schizophrenia, we examined if it was related to parental ages in patients and healthy controls. We tested Leukocyte Telomere Length (LTL) as an explanatory factor, as LTL is associated with paternal age and schizophrenia risk. Seventy-five DSM-IV patients and 46 controls were assessed for detection of PEA, WAIS-III for cognition, and LTL, assessed by qPCR. In healthy controls, but not schizophrenia patients, decreasing sensitivity was monotonically related to advancing parental ages, particularly in sons. The relationships between parental aging and odor sensitivity differed significantly for patients and controls (Fisher's R to Z: χ(2) = 6.95, P = 0.009). The groups also differed in the association of odor sensitivity with cognition; lesser sensitivity robustly predicted cognitive impairments in patients (<0.001), but these were unassociated in controls. LTL was unrelated to odor sensitivity and did not explain the association of lesser sensitivity with cognitive deficits.Parental aging predicted less sensitive detection in healthy subjects but not in schizophrenia patients. In patients, decreased odor sensitivity strongly predicted cognitive deficits, whereas more sensitive acuity was associated with older parents. These data support separate risk pathways for schizophrenia. A parental age-related pathway may produce psychosis without impairing cognition and odor sensitivity. Diminished odor sensitivity may furthermore be useful as a biomarker for research and treatment studies in schizophrenia. © 2015 Wiley Periodicals, Inc.

Research paper thumbnail of Impairment in emotional modulation of attention and memory in schizophrenia

Schizophrenia Research

Emotion plays a critical role in cognition and goal-directed behavior via complex interconnection... more Emotion plays a critical role in cognition and goal-directed behavior via complex interconnections between the emotional and motivational systems. It has been hypothesized that the impairment in goal-directed behavior widely noted in schizophrenia may result from defects in the interaction between the neural (ventral) emotional system and (rostral) cortical processes. The present study examined the impact of emotion on attention and memory in schizophrenia. Twenty-five individuals with schizophrenia related psychosis and 25 healthy control subjects were administered a computerized task in which they were asked to search for target images during a Rapid Serial Visual Presentation of pictures. Target stimuli were either positive or negative, or neutral images presented at either 200 ms or 700 ms lag. Additionally, a visual hedonic task was used to assess differences between the schizophrenia group and controls on ratings of valence and arousal from the picture stimuli. Compared to con...

Research paper thumbnail of Paternal age effect: Replication in schizophrenia with intriguing dissociation between bipolar with and without psychosis

American journal of medical genetics. Part B, Neuropsychiatric genetics : the official publication of the International Society of Psychiatric Genetics, Jan 16, 2015

Advanced paternal age (APA) is a risk factor for schizophrenia (Sz) and bipolar disorder (BP). Pu... more Advanced paternal age (APA) is a risk factor for schizophrenia (Sz) and bipolar disorder (BP). Putative mechanisms include heritable genetic factors, de novo mutations, and epigenetic mechanisms. Few studies have explored phenotypic features associated with APA. The Genomic Psychiatry Cohort established a clinically characterized repository of genomic samples from subjects with a Sz-BP diagnosis or unaffected controls, 12,975 with parental age information. We estimated relative risk ratios for Sz, schizoaffective depressed and bipolar types (SA-D, SA-B), and BP with and without history of psychotic features (PF) relative to the control group, comparing each paternal age group to the reference group 20-24 years. All tests were two-sided with adjustment for multiple comparisons. Subjects with fathers age 45+ had significantly higher risk for all diagnoses except for BP w/o PF. APA also bore no significant relation to family psychiatric history. In conclusion, we replicated APA as a ri...

Research paper thumbnail of The effect of cognitive impairment on PAI profile validity and response style

Research paper thumbnail of De novo mutations from sporadic schizophrenia cases highlight important signaling genes in an independent sample

Schizophrenia research, Jan 16, 2015

Schizophrenia is a debilitating syndrome with high heritability. Genomic studies reveal more than... more Schizophrenia is a debilitating syndrome with high heritability. Genomic studies reveal more than a hundred genetic variants, largely nonspecific and of small effect size, and not accounting for its high heritability. De novo mutations are one mechanism whereby disease related alleles may be introduced into the population, although these have not been leveraged to explore the disease in general samples. This paper describes a framework to find high impact genes for schizophrenia. This study consists of two different datasets. First, whole exome sequencing was conducted to identify disruptive de novo mutations in 14 complete parent-offspring trios with sporadic schizophrenia from Jerusalem, which identified 5 sporadic cases with de novo gene mutations in 5 different genes (PTPRG, TGM5, SLC39A13, BTK, CDKN3). Next, targeted exome capture of these genes was conducted in 48 well-characterized, unrelated, ethnically diverse schizophrenia cases, recruited and characterized by the same res...

Research paper thumbnail of Olfactory performance segregates effects of anhedonia and anxiety on social function in patients with schizophrenia

Journal of psychiatry & neuroscience : JPN, Jan 23, 2015

Social dysfunction is common among individuals with schizophrenia. While often attributed to anhe... more Social dysfunction is common among individuals with schizophrenia. While often attributed to anhedonia, social dysfunction could also result from unrecognized anxiety. We examined the contributions of anhedonia and anxiety to social function using olfactory function to examine whether the domains had separate underpinnings. We assessed anhedonia, anxiety and social function as well as olfactory function in well-characterized patients with schizophrenia or schizoaffective disorder and healthy controls. We included 56 patients and 37 controls in our study. Patients exhibited significantly higher levels of anhedonia and anxiety than controls, and the domains were highly correlated in patients. The combination of anhedonia and anxiety more strongly predicted social dysfunction than either measure alone. Smell identification was differentially related to the symptoms, with better performance predicting less anhedonia but more social fear in male patients. The use of self-report measures ...

Research paper thumbnail of Core Features of Schizophrenia are Associated with Leukocyte Telomere Length

Background: We recently showed longer leukocyte telomere length (LTL) for schizophrenia cases wit... more Background: We recently showed longer leukocyte telomere length (LTL) for schizophrenia cases with a family history of psychiatric illness and for paternal aging. Herein symptoms and cognition were examined with respect to LTL. Methods: Elongated LTL (e-LTL) was defined as LTL values that were outliers in the normal distribution of LTL using an interquartile range of 1.5. Symptoms were assessed using the PANSS and cognition was assessed with the WAIS-III. Results: Schizophrenia cases (n=53) and healthy controls (n=20) did not differ in mean LTL, but one in seven cases (5 males and 2 females) had e-LTL. Male cases with e-LTL demonstrated older fathers (38.0 +/- 2.8 vs. 30.1 +/- 8.9, p = .001); less positive symptoms (8.0 +/- 2.0 vs. 12.7 +/- 4.9, p = .047); less autistic symptoms (7.4 +/- 1.5 vs. 10.8 +/- 2.9, p = .016) and had higher FSIQ (101.3 +/- 19.2 vs. 84.9 +/- 14.6, p = .057) and VIQ (105.8 +/-19.7 vs. 85.6 +/- 15.5, p = .027) than other cases. Female cases with e-LTL showed ...

Research paper thumbnail of Telomere length variability is related to symptoms and cognition in schizophrenia

Schizophrenia Research, 2015

Research paper thumbnail of Hypo-metabolism of the rostral anterior cingulate cortex associated with working memory impairment in 18 cases of schizophrenia

Brain imaging and behavior, Jan 25, 2015

Working memory (Work-Mem), the capacity to hold and manipulate information, activates the anterio... more Working memory (Work-Mem), the capacity to hold and manipulate information, activates the anterior cingulate cortex (ACC), especially its caudal subregion. Impaired Work-Mem and structural and functional abnormalities of the ACC are reported in schizophrenia. This study aims to elucidate the pathogenesis of Work-Mem dysfunction in schizophrenia by comparing metabolite concentrations across ACC subregions. This retrospective study of 18 schizophrenia cases and 10 matched controls used proton magnetic resonance spectroscopic imaging ((1)H-MRSI, TR/TE = 1800/35 ms, 0.5 cm(3) spatial resolution) to test whether the Work-Mem Index of the Wechsler Adult Intelligence Scale, third edition is associated with differences in the rostral to caudal ACC ratios of N-acetylaspartate (NAA) and creatine (Cr). Higher caudal:rostral ACC Cr (but not NAA) concentrations were associated with decreased Work-Mem Index in cases (r = -0.6, p = 0.02), with a similar trend in controls (r = -0.56, p = 0.10), alt...

Research paper thumbnail of Theory of Mind in patients at clinical high risk for psychosis

Schizophrenia research, 2011

Patients with schizophrenia have a decreased ability to interpret the intentions of other individ... more Patients with schizophrenia have a decreased ability to interpret the intentions of other individuals, called Theory of Mind (ToM). As capacity for ToM normally advances with brain maturation, research on ToM in individuals at heightened clinical risk for psychosis may reveal developmental differences independent of disease based differences. We examined ToM in at clinical high risk and schizophrenia patients as well as healthy controls: 1) 63 clinical high risk (CHR) patients and 24 normal youths ascertained by a CHR program; and 2) in 13 schizophrenia cases and 14 normal adults recruited through a schizophrenia program. ToM measures included first- and second-order false belief cartoon tasks (FBT) and two "higher order" tasks ("Strange Stories Task" (SST) and the "Reading the Mind in the Eyes" task). In the first study, CHR patients and normal youths were also assessed for cognition, "prodromal" symptoms and social function. Errors on first-...

Research paper thumbnail of Telomere length, family history, and paternal age in schizophrenia

Molecular genetics & genomic medicine, 2014

Leukocyte telomere length (LTL) is longer in association with advanced paternal age, but this ass... more Leukocyte telomere length (LTL) is longer in association with advanced paternal age, but this association has not been examined along with family history (FH) in schizophrenia. LTL was measured by PCR and compared across cases and controls as part of a study to examine the characteristics of paternal age related schizophrenia. The 53 schizophrenia cases had similar mean LTL as 20 controls, although cases were significantly older than controls and overwhelmingly smoked cigarettes. Multivariate analyses showed that a FH of schizophrenia was associated with longer LTL in both male and female cases. Later paternal age was also related to longer LTL in male cases, but with shorter LTL in female cases. Male cases with older fathers and a FH had the longest LTL. The genetic architecture associated with a familial risk for schizophrenia may include pathways that lengthen LTL. Paternal aging conferred an additional increase in LTL lengthening in male cases, but reduced LTL in female cases. T...

Research paper thumbnail of Low Vitamin D levels predict clinical features of schizophrenia

Schizophrenia Research, 2014

and sharing with colleagues.

Research paper thumbnail of Temporal association of cannabis use with symptoms in individuals at clinical high risk for psychosis

Schizophrenia Research, 2008

Background-Cannabis use is reported to increase the risk for psychosis, but no prospective study ... more Background-Cannabis use is reported to increase the risk for psychosis, but no prospective study has longitudinally examined drug use and symptoms concurrently in clinical high risk cases.

Research paper thumbnail of Olfactory processing, sex effects and heterogeneity in schizophrenia

Schizophrenia Research, 2012

Introduction-Smell identification deficits are associated with negative symptoms in schizophrenia... more Introduction-Smell identification deficits are associated with negative symptoms in schizophrenia, particularly in males. Far less information is known about the relationship of odor detection sensitivity (acuity) and negative symptoms in schizophrenia, and currently there is a dearth in sex-stratified research specifically examining odor sensitivity and smell identification.

Research paper thumbnail of telomere%20length%20paper%20%20mgg371

Research paper thumbnail of Diminished range of emotion responses to negative odorants in schizophrenia

Research paper thumbnail of Rare variants in the neurotrophin signaling pathway implicated in schizophrenia risk

Schizophrenia Research, 2015

Multiple lines of evidence corroborate impaired signaling pathways as relevant to the underpinnin... more Multiple lines of evidence corroborate impaired signaling pathways as relevant to the underpinnings of schizophrenia. There has been an interest in neurotrophins, since they are crucial mediators of neurodevelopment and in synaptic connectivity in the adult brain. Neurotrophins and their receptors demonstrate aberrant expression patterns in cortical areas for schizophrenia cases in comparison to control subjects. There is little known about the contribution of neurotrophin genes in psychiatric disorders. To begin to address this issue, we conducted high-coverage targeted exome capture in a subset of neurotrophin genes in 48 comprehensively characterized cases with schizophrenia-related psychosis. We herein report rare missense polymorphisms and novel missense mutations in neurotrophin receptor signaling pathway genes. Furthermore, we observed that several genes have a higher propensity to harbor missense coding variants than others. Based on this initial analysis we suggest that rare variants and missense mutations in neurotrophin genes might represent genetic contributions involved across psychiatric disorders.

Research paper thumbnail of Following in the footsteps of Kraepelin and Bleuler: Evidence for separate dimensions of affective and volitional deficits in DSM-V schizophrenia

Research paper thumbnail of Validation of the Curious Experiences Survey (CES) in an urban minority population

Research paper thumbnail of Diagnosis of Psychoses

Research paper thumbnail of Parental age effects on odor sensitivity in healthy subjects and schizophrenia patients

American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 2015

A schizophrenia phenotype for paternal and maternal age effects on illness risk could benefit eti... more A schizophrenia phenotype for paternal and maternal age effects on illness risk could benefit etiological research. As odor sensitivity is associated with variability in symptoms and cognition in schizophrenia, we examined if it was related to parental ages in patients and healthy controls. We tested Leukocyte Telomere Length (LTL) as an explanatory factor, as LTL is associated with paternal age and schizophrenia risk. Seventy-five DSM-IV patients and 46 controls were assessed for detection of PEA, WAIS-III for cognition, and LTL, assessed by qPCR. In healthy controls, but not schizophrenia patients, decreasing sensitivity was monotonically related to advancing parental ages, particularly in sons. The relationships between parental aging and odor sensitivity differed significantly for patients and controls (Fisher's R to Z: χ(2) = 6.95, P = 0.009). The groups also differed in the association of odor sensitivity with cognition; lesser sensitivity robustly predicted cognitive impairments in patients (<0.001), but these were unassociated in controls. LTL was unrelated to odor sensitivity and did not explain the association of lesser sensitivity with cognitive deficits.Parental aging predicted less sensitive detection in healthy subjects but not in schizophrenia patients. In patients, decreased odor sensitivity strongly predicted cognitive deficits, whereas more sensitive acuity was associated with older parents. These data support separate risk pathways for schizophrenia. A parental age-related pathway may produce psychosis without impairing cognition and odor sensitivity. Diminished odor sensitivity may furthermore be useful as a biomarker for research and treatment studies in schizophrenia. © 2015 Wiley Periodicals, Inc.

Research paper thumbnail of Impairment in emotional modulation of attention and memory in schizophrenia

Schizophrenia Research

Emotion plays a critical role in cognition and goal-directed behavior via complex interconnection... more Emotion plays a critical role in cognition and goal-directed behavior via complex interconnections between the emotional and motivational systems. It has been hypothesized that the impairment in goal-directed behavior widely noted in schizophrenia may result from defects in the interaction between the neural (ventral) emotional system and (rostral) cortical processes. The present study examined the impact of emotion on attention and memory in schizophrenia. Twenty-five individuals with schizophrenia related psychosis and 25 healthy control subjects were administered a computerized task in which they were asked to search for target images during a Rapid Serial Visual Presentation of pictures. Target stimuli were either positive or negative, or neutral images presented at either 200 ms or 700 ms lag. Additionally, a visual hedonic task was used to assess differences between the schizophrenia group and controls on ratings of valence and arousal from the picture stimuli. Compared to con...

Research paper thumbnail of Paternal age effect: Replication in schizophrenia with intriguing dissociation between bipolar with and without psychosis

American journal of medical genetics. Part B, Neuropsychiatric genetics : the official publication of the International Society of Psychiatric Genetics, Jan 16, 2015

Advanced paternal age (APA) is a risk factor for schizophrenia (Sz) and bipolar disorder (BP). Pu... more Advanced paternal age (APA) is a risk factor for schizophrenia (Sz) and bipolar disorder (BP). Putative mechanisms include heritable genetic factors, de novo mutations, and epigenetic mechanisms. Few studies have explored phenotypic features associated with APA. The Genomic Psychiatry Cohort established a clinically characterized repository of genomic samples from subjects with a Sz-BP diagnosis or unaffected controls, 12,975 with parental age information. We estimated relative risk ratios for Sz, schizoaffective depressed and bipolar types (SA-D, SA-B), and BP with and without history of psychotic features (PF) relative to the control group, comparing each paternal age group to the reference group 20-24 years. All tests were two-sided with adjustment for multiple comparisons. Subjects with fathers age 45+ had significantly higher risk for all diagnoses except for BP w/o PF. APA also bore no significant relation to family psychiatric history. In conclusion, we replicated APA as a ri...

Research paper thumbnail of The effect of cognitive impairment on PAI profile validity and response style

Research paper thumbnail of De novo mutations from sporadic schizophrenia cases highlight important signaling genes in an independent sample

Schizophrenia research, Jan 16, 2015

Schizophrenia is a debilitating syndrome with high heritability. Genomic studies reveal more than... more Schizophrenia is a debilitating syndrome with high heritability. Genomic studies reveal more than a hundred genetic variants, largely nonspecific and of small effect size, and not accounting for its high heritability. De novo mutations are one mechanism whereby disease related alleles may be introduced into the population, although these have not been leveraged to explore the disease in general samples. This paper describes a framework to find high impact genes for schizophrenia. This study consists of two different datasets. First, whole exome sequencing was conducted to identify disruptive de novo mutations in 14 complete parent-offspring trios with sporadic schizophrenia from Jerusalem, which identified 5 sporadic cases with de novo gene mutations in 5 different genes (PTPRG, TGM5, SLC39A13, BTK, CDKN3). Next, targeted exome capture of these genes was conducted in 48 well-characterized, unrelated, ethnically diverse schizophrenia cases, recruited and characterized by the same res...

Research paper thumbnail of Olfactory performance segregates effects of anhedonia and anxiety on social function in patients with schizophrenia

Journal of psychiatry & neuroscience : JPN, Jan 23, 2015

Social dysfunction is common among individuals with schizophrenia. While often attributed to anhe... more Social dysfunction is common among individuals with schizophrenia. While often attributed to anhedonia, social dysfunction could also result from unrecognized anxiety. We examined the contributions of anhedonia and anxiety to social function using olfactory function to examine whether the domains had separate underpinnings. We assessed anhedonia, anxiety and social function as well as olfactory function in well-characterized patients with schizophrenia or schizoaffective disorder and healthy controls. We included 56 patients and 37 controls in our study. Patients exhibited significantly higher levels of anhedonia and anxiety than controls, and the domains were highly correlated in patients. The combination of anhedonia and anxiety more strongly predicted social dysfunction than either measure alone. Smell identification was differentially related to the symptoms, with better performance predicting less anhedonia but more social fear in male patients. The use of self-report measures ...

Research paper thumbnail of Core Features of Schizophrenia are Associated with Leukocyte Telomere Length

Background: We recently showed longer leukocyte telomere length (LTL) for schizophrenia cases wit... more Background: We recently showed longer leukocyte telomere length (LTL) for schizophrenia cases with a family history of psychiatric illness and for paternal aging. Herein symptoms and cognition were examined with respect to LTL. Methods: Elongated LTL (e-LTL) was defined as LTL values that were outliers in the normal distribution of LTL using an interquartile range of 1.5. Symptoms were assessed using the PANSS and cognition was assessed with the WAIS-III. Results: Schizophrenia cases (n=53) and healthy controls (n=20) did not differ in mean LTL, but one in seven cases (5 males and 2 females) had e-LTL. Male cases with e-LTL demonstrated older fathers (38.0 +/- 2.8 vs. 30.1 +/- 8.9, p = .001); less positive symptoms (8.0 +/- 2.0 vs. 12.7 +/- 4.9, p = .047); less autistic symptoms (7.4 +/- 1.5 vs. 10.8 +/- 2.9, p = .016) and had higher FSIQ (101.3 +/- 19.2 vs. 84.9 +/- 14.6, p = .057) and VIQ (105.8 +/-19.7 vs. 85.6 +/- 15.5, p = .027) than other cases. Female cases with e-LTL showed ...

Research paper thumbnail of Telomere length variability is related to symptoms and cognition in schizophrenia

Schizophrenia Research, 2015

Research paper thumbnail of Hypo-metabolism of the rostral anterior cingulate cortex associated with working memory impairment in 18 cases of schizophrenia

Brain imaging and behavior, Jan 25, 2015

Working memory (Work-Mem), the capacity to hold and manipulate information, activates the anterio... more Working memory (Work-Mem), the capacity to hold and manipulate information, activates the anterior cingulate cortex (ACC), especially its caudal subregion. Impaired Work-Mem and structural and functional abnormalities of the ACC are reported in schizophrenia. This study aims to elucidate the pathogenesis of Work-Mem dysfunction in schizophrenia by comparing metabolite concentrations across ACC subregions. This retrospective study of 18 schizophrenia cases and 10 matched controls used proton magnetic resonance spectroscopic imaging ((1)H-MRSI, TR/TE = 1800/35 ms, 0.5 cm(3) spatial resolution) to test whether the Work-Mem Index of the Wechsler Adult Intelligence Scale, third edition is associated with differences in the rostral to caudal ACC ratios of N-acetylaspartate (NAA) and creatine (Cr). Higher caudal:rostral ACC Cr (but not NAA) concentrations were associated with decreased Work-Mem Index in cases (r = -0.6, p = 0.02), with a similar trend in controls (r = -0.56, p = 0.10), alt...

Research paper thumbnail of Theory of Mind in patients at clinical high risk for psychosis

Schizophrenia research, 2011

Patients with schizophrenia have a decreased ability to interpret the intentions of other individ... more Patients with schizophrenia have a decreased ability to interpret the intentions of other individuals, called Theory of Mind (ToM). As capacity for ToM normally advances with brain maturation, research on ToM in individuals at heightened clinical risk for psychosis may reveal developmental differences independent of disease based differences. We examined ToM in at clinical high risk and schizophrenia patients as well as healthy controls: 1) 63 clinical high risk (CHR) patients and 24 normal youths ascertained by a CHR program; and 2) in 13 schizophrenia cases and 14 normal adults recruited through a schizophrenia program. ToM measures included first- and second-order false belief cartoon tasks (FBT) and two "higher order" tasks ("Strange Stories Task" (SST) and the "Reading the Mind in the Eyes" task). In the first study, CHR patients and normal youths were also assessed for cognition, "prodromal" symptoms and social function. Errors on first-...

Research paper thumbnail of Telomere length, family history, and paternal age in schizophrenia

Molecular genetics & genomic medicine, 2014

Leukocyte telomere length (LTL) is longer in association with advanced paternal age, but this ass... more Leukocyte telomere length (LTL) is longer in association with advanced paternal age, but this association has not been examined along with family history (FH) in schizophrenia. LTL was measured by PCR and compared across cases and controls as part of a study to examine the characteristics of paternal age related schizophrenia. The 53 schizophrenia cases had similar mean LTL as 20 controls, although cases were significantly older than controls and overwhelmingly smoked cigarettes. Multivariate analyses showed that a FH of schizophrenia was associated with longer LTL in both male and female cases. Later paternal age was also related to longer LTL in male cases, but with shorter LTL in female cases. Male cases with older fathers and a FH had the longest LTL. The genetic architecture associated with a familial risk for schizophrenia may include pathways that lengthen LTL. Paternal aging conferred an additional increase in LTL lengthening in male cases, but reduced LTL in female cases. T...

Research paper thumbnail of Low Vitamin D levels predict clinical features of schizophrenia

Schizophrenia Research, 2014

and sharing with colleagues.

Research paper thumbnail of Temporal association of cannabis use with symptoms in individuals at clinical high risk for psychosis

Schizophrenia Research, 2008

Background-Cannabis use is reported to increase the risk for psychosis, but no prospective study ... more Background-Cannabis use is reported to increase the risk for psychosis, but no prospective study has longitudinally examined drug use and symptoms concurrently in clinical high risk cases.

Research paper thumbnail of Olfactory processing, sex effects and heterogeneity in schizophrenia

Schizophrenia Research, 2012

Introduction-Smell identification deficits are associated with negative symptoms in schizophrenia... more Introduction-Smell identification deficits are associated with negative symptoms in schizophrenia, particularly in males. Far less information is known about the relationship of odor detection sensitivity (acuity) and negative symptoms in schizophrenia, and currently there is a dearth in sex-stratified research specifically examining odor sensitivity and smell identification.