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1.  An investigation of habit learning in Anorexia Nervosa 
Psychiatry research  2016;244:214-222.
Anorexia Nervosa (AN) is a disorder characterised by compulsive behaviour, such as self-starvation and excessive exercise, which develop in the pursuit of weight-loss. Recent theory suggests that once established, compulsive weight-loss behaviours in AN may become habitual. In two parallel studies, we measured whether individuals with AN showed a bias toward habits using two outcome-devaluation tasks. In Study 1, 23 women with AN (restrictive and binge/purge subtypes), and 18 healthy controls (HC) completed the slips-of-action paradigm, designed to assess reward-based habits. In Study 2, 13 women with restrictive AN, 14 women recovered from restrictive AN, and 17 female HC participants completed the slips-of-action paradigm, and an avoidance paradigm, designed to assess aversive habits. AN participants showed no deficit relative to HCs in the ability to use feedback to respond correctly to stimuli. Following devaluation of outcomes, all groups in both studies were equally able to withhold inappropriate responses, suggesting no deficit in the balance between goal-directed and habitual control of behaviour in these tasks in AN. These results suggest that individuals with AN do not show a generalised tendency to rely on habits in two outcome-devaluation tasks. Future research is needed to investigate the potential role of disorder-specific habits in the maintenance of behaviour in AN.
PMCID: PMC5718042  PMID: 27497292
Anorexia Nervosa; Habit Formation; Compulsivity; Goal-directed learning; Eating Disorders
3.  Treadmill Exercise Improves Fitness and Reduces Craving and Use of Cocaine in Individuals with Concurrent Cocaine and Tobacco-use Disorder 
Psychiatry research  2016;245:133-140.
Exercise may be a useful treatment for substance use disorders. Participants (N=24) included treatment-seeking individuals with concurrent cocaine and tobacco-use disorder (cigarette smokers). Participants were randomized to either running or walking (30 min per session, 3 times per week) or sitting (control condition) for 4 consecutive weeks. Several metrics indicated significant differences among runners, walkers, and sitters during sessions, including mean distance covered and calories burned. In addition, remote physiological monitoring showed that the groups differed significantly according to mean maximum heart rate (HR), respiration, and locomotor activity. Across the 4-week study, exercise improved fitness measures including significantly decreasing resting HR. Though not statistically significant, exercise improved abstinence from cocaine and increased self-reports of no cocaine use in last 24h. In general, reductions in tobacco use and craving were not as robust. To our knowledge, this is the first study to evaluate the effects of a multi-week exercise program in individuals with concurrent cocaine and tobacco-use disorder. The data clearly show significant improvements in basic fitness measures and several indices reveal that exercise improved both self-report and biochemically verified reports of cocaine abstinence. Taken together, the data from this study provides preliminary evidence for the efficacy of exercise for improving fitness and reducing cocaine use.
PMCID: PMC5067203  PMID: 27541349
4.  Brain Derived Neurotrophic Factor moderates associations between maternal smoking during pregnancy and offspring behavioral disorders 
Psychiatry research  2016;245:387-391.
Maternal smoking during pregnancy is associated with a number of adverse offspring outcomes. In the present study, based on 209 offspring from a 3-generation family study of depression, we show that the effects of prenatal exposure on offspring externalizing psychopathology (conduct, substance use disorder) is more pronounced in the presence of lower-expressing brain derived neurotrophic factor (BDNF) gene variants. BDNF plays an important role in the development and survival of neural circuits. Individuals with low-expressing variants who are further exposed to prenatal tobacco smoke may be most vulnerable to a spectrum of behavioral disorders that depend on these circuits.
PMCID: PMC5067210  PMID: 27611068
in utero exposure; val66met
5.  Youth with Substance Abuse Histories Exhibit Dysfunctional Representation of Expected Value During a Passive Avoidance Task 
Psychiatry research  2016;257:17-24.
Individuals with substance abuse (SA) histories show impairment in the computations necessary for decision-making, including expected value (EV) and prediction error (PE). Neuroimaging findings, however, have been inconsistent. Sixteen youth with (SApositive) and 29 youth without (SAnegative) substance abuse histories completed a passive avoidance task while undergoing functional MRI. The groups did not significantly differ on age, gender composition or IQ. Behavioral results indicated that SApositive youth showed significantly less learning than SAnegative youth over the task. SApositive youth show problems representing EV information when attempting to avoid sub-optimal choices in bilateral inferior frontal gyrus and striatum. Furthermore, SApositive youth showed a significantly increased differential response to reward versus punishment feedback modulated by PE in posterior cingulate cortex relative to SAnegative youth. Disrupted decision-making is likely to exacerbate SA as a failure to represent EV during the avoidance of sub-optimal choices is likely to increase the likelihood of SA. With respect to the representation of PE, future work will be needed to clarify the impact of different substances on the neural systems underpinning PE representation. Moreover, interaction of age/development and substance abuse on PE signaling will need to be explored.
PMCID: PMC5102791  PMID: 27716545
substance abuse; decision-making; expected value; prediction error
6.  Expression and Methylation in Posttraumatic Stress Disorder and Resilience; Evidence of a role for Odorant Receptors 
Psychiatry research  2016;245:36-44.
Post-traumatic stress disorder (PTSD) is a common and potentially disabling disorder that develops in 1/5 to 1/3 of people exposed to severe trauma. Twin studies indicate that genetic factors account for at least one third of the variance in the risk for developing PTSD, however, the specific role for genetic factors in the pathogenesis of PTSD is not well understood. We studied genome-wide gene expression and DNA methylation profiles in 12 participants with PTSD and 12 participants who were resilient to similar severity trauma exposure. Close to 4,000 genes were differentially expressed with adjusted p < 0.05, fold-change > 2, with all but 3 upregulated with PTSD. Eight odorant/olfactory receptor related genes were up-regulated with PTSD as well as genes related to immune activation, the Gamma-Aminobutyric Acid A (GABAA) receptor, and vitamin D synthesis. No differences with adjusted significance for DNA methylation were found. We conclude that increased gene expression may play an important role in PTSD and this expression may not be a consequence of DNA methylation. The role of odorant receptor expression warrants independent replication.
PMCID: PMC5148136  PMID: 27526315
Microarray; Biomarker; Epigenetic; odorant receptor; GABAA receptor; Vitamin D Synthesis
7.  A structural MRI study of excoriation (skin-picking) disorder and its relationship to clinical severity 
Psychiatry research  2017;269:26-30.
Excoriation (skin-picking) disorder (SPD) shares symptomology with other obsessive-compulsive and related disorders. Few studies, however, have examined the neurological profile of patients with SPD. This study examined differences in cortical thickness and basal ganglia structural volumes between 20 individuals with SPD and 16 healthy controls using magnetic resonance imaging (MRI). There were no significant differences in demographic variables (age, gender, education and race) between groups. All subjects completed a structural MRI scan and completed a battery of clinical assessments focusing on SPD symptom severity, depression and anxiety symptoms, and quality of life. No statistically significant differences in basal ganglia (caudate, putamen, and nucleus accumbens) structural volumes were found between groups. In individuals with SPD, increasing impulsiveness correlated positively with increased cortical thickness in the left insula, and skin picking severity correlated negatively with cortical thickness in the left supramarginal gyrus and a region encompassing the right inferior parietal, right temporal and right supramarginal gyrus. This study suggests similarities and differences exist in symptomology between SPD and the other obsessive-compulsive and related disorders. Additional neuroimaging research is needed to better delineate the underlying neurobiology of SPD.
PMCID: PMC5604737  PMID: 28918268
Skin picking disorder; obsessive-compulsive; cortical thickness; structural volume; brain imaging
8.  Neural dysfunction during temporal discounting in paediatric Attention-Deficit/Hyperactivity Disorder and Obsessive-Compulsive Disorder 
Psychiatry Research  2017;269:97-105.
Both Attention-Deficit/Hyperactivity Disorder (ADHD) and Obsessive-Compulsive Disorder (OCD) are associated with choice impulsivity, i.e. the tendency to prefer smaller immediate rewards over larger delayed rewards. However, the extent to which this impulsivity is mediated by shared or distinct underlying neural mechanisms is unclear. Twenty-six boys with ADHD, 20 boys with OCD and 20 matched controls (aged 12–18) completed an fMRI version of an individually adjusted temporal discounting (TD) task which requires choosing between a variable amount of money now or £100 in one week, one month or one year. Activations to immediate and delayed reward choices were compared between groups using a three-way ANCOVA. ADHD patients had steeper discounting rates on the task relative to controls. OCD patients did not differ from controls or patients with ADHD. Patients with ADHD and OCD showed predominantly shared activation deficits during TD in fronto-striato-insular-cerebellar regions responsible for self-control and temporal foresight, suggesting that choice impulsivity is mediated by overlapping neural dysfunctions in both disorders. OCD patients alone showed dysfunction relative to controls in right orbitofrontal and rostrolateral prefrontal cortex, extending previous findings of abnormalities in these regions in OCD to the domain of choice impulsiveness.
•ADHD patients alone showed significantly steeper discounting relative to controls.•ADHD and OCD shared underactivation in fronto-striato-insular-cerebellar regions during delayed choices.•Only patients with OCD had dysfunction in right orbitofrontal and rostrolateral prefrontal cortex relative to controls.
PMCID: PMC5647646  PMID: 28988149
ADHD; OCD; fMRI; Discounting; Reward; Impulsivity
9.  Pain moderates changes in psychological flexibility but not substance use symptoms during substance use disorder treatment 
Psychiatry research  2016;245:51-57.
Pain-related problems frequently complicate substance use disorder (SUD) course and prognosis. However, it is unclear if the negative outcomes associated with co-occurring pain are due to its link with greater SUD severity, disruption of SUD treatment processes, or connection to a third psychological process. The current study modeled the longitudinal effects of pain during a 4-week intensive outpatient treatment (IOP) on SUD symptoms and limited psychological flexibility (PF), a common feature of psychological well being that is commonly restricted in both SUD and pain patients. After controlling for initial severity of SUD symptoms, current pain level at treatment intake moderated change in a subcomponent of PF, values commitment, but not SUD symptoms during the IOP. During the treatment, pain level also limited improvement in PF but not self-reported SUD symptoms. Targeting additional increases in psychological flexibility surrounding commitment to values during SUD treatment may help improve outcomes among patients who began treatment with significant pain symptoms.
PMCID: PMC5705042  PMID: 27526317
Substance use disorder treatment; Outcomes; Intensive outpatient; Pain; Psychological flexibility
10.  Affective information processing in pregnancy and postpartum with and without major depression 
Psychiatry research  2013;206(2-3):206-212.
Adults with clinical depression exhibit systematic errors in their recognition and interpretation of affective stimuli. This study investigated the extent to which depression and phases of pregnancy and postpartum influence affective processing of positive and negative information, and the extent to which affective information processing in pregnancy predicts depressive symptoms in postpartum. Data were collected from 80 unmedicated women, diagnosed with major depressive disorder (MDD) or with no psychiatric disorder and between ages 18 and 44 years, during 32–36 weeks of pregnancy and during 6–8 weeks postpartum. All completed a Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) Axis I review, symptom reports, and a computer task measuring affective information processing. Significant group differences were found in which postpartum women with major depression were less responsive to negative and reactions to negative pictorial stimuli, compared with postpartum healthy women. Also, lower ratings of the intensity and reactions to negative stimuli during pregnancy among depressed women predicted postpartum depression severity, even after controlling for depressive severity and affect ratings in pregnancy. Blunted affective reactivity to negative stimuli is a characteristic of depression that was observed among depressed women during pregnancy and postpartum in our study.
PMCID: PMC5697721  PMID: 23340374
Major depression; Pregnancy; Postpartum; Affective disorders; Emotion; Processing
11.  Measuring insight through patient self-report: An in-depth analysis of the factor structure of the Birchwood Insight Scale 
Psychiatry research  2014;216(2):263-268.
Little research has focused on item analysis and factor structure of the most commonly used measures of insight. We examined the factorial structure of the Birchwood Insight Scale (BIS), a brief, easy-to-administer, self-report measure. We studied the BIS in 327 first-episode psychosis patients, including a test sample (n=163) and a validation sample (n=164). We then used data from 100 patients with chronic serious mental illnesses as a second, external validation sample. Exploratory factor analysis was conducted with the test subsample, and confirmatory factor analyses with the two validation samples. Confirmatory factor analyses (in both the first-episode psychosis validation sample and the chronic serious mental illness sample) indicated that a single-factor solution, with seven items loading on a single factor—with item 1 (“Some of your symptoms are made by your mind”) eliminated—was the best-fitting model. Seven of the eight original BIS items loading on a single factor fit the data well in these samples. Researchers using this efficient measure of patient-reported insight should assess the item distributions and factor structure of the BIS in their samples, and potentially consider eliminating item 1.
PMCID: PMC5695544  PMID: 24602993
Awareness of illness; Birchwood Insight Scale; First-episode psychosis; Insight; Psychosis; Schizophrenia; Serious mental illness
12.  The influence of types of war experiences on conduct problems in war-affected youth in Northern Ugandan: Findings from the WAYS study 
Psychiatry research  2017;251:14-19.
Exposure to war is associated with poor psychosocial outcomes. Yet the effects of different types of war events on various psychosocial outcomes such as conduct problems remain unknown. This study aims to assess whether various war events differ in predicting conduct problems. Using data from an on-going longitudinal research project, the WAYS study, the current article examined the relationship between specific war events and conduct problems in war-affected youth in Northern Uganda (N=539, baseline age=22.39; SD=2.03, range 18– 25). Regression analyses were conducted to relate each type of war experience to conduct problems. War categories of “witnessing violence”, “deaths”, “threat to loved ones” and “sexual abuse” were associated with reporting conduct problems. Multivariable models yielded independent effects of “witnessing violence” (β=0.09, 95% CI: 0.01, 0.18) and “Sexual abuse” (β=0.09, 95% CI: 0.02, 0.19) on conduct problems while “duration in captivity” independently and negatively predicted conduct problems (β=−0.14, 95% CI: −0.23, −0.06). Types of war events vary in predicting conduct problems and should be considered when designing interventions to alleviate negative consequences of exposure to war. Moreover, longer duration in captivity appear to protect war-affected youth from conduct problems.
PMCID: PMC5369637  PMID: 28171768
War experiences; War-affected youth; Conduct problem
13.  The relationship between executive functions and fluid intelligence in euthymic Bipolar Disorder patients 
Psychiatry Research  2017;257:346-351.
Distinct cognitive deficits have been described in Bipolar disorder (BD), including executive impairments, commonly attributed to frontal dysfunction. However, recent attention has been paid to the heterogeneity of cognitive functioning in this population, suggesting that the executive deficits observed in BD might be due to a loss in fluid intelligence (g). Following our previous line of investigation in multiple neurological and psychiatric conditions we aimed at determining the role of g in frontal deficits in BD. Euthymic BD patients (n = 51) and healthy controls (n = 37) were assessed with Wisconsin Card Sorting Test (WCST), Verbal Fluency, Trail Making Test B (TMTB), a multitasking test, and a theory of mind test. A general cognitive battery was used to derive a measure of g. As in other neuropsychiatric conditions, significant patient-control differences in WCST, Verbal Fluency and TMTB were removed when g was introduced as a covariate. Deficits remained significant in the multitasking test. We suggest that neuropsychological assessment in BD should include tests of general intelligence, together with one or more specific tasks that allow for the assessment of residual frontal deficits, putatively associated with anterior frontal functioning.
•We aimed at determining the role of Spearman's g in frontal deficits found in BD.•Deficits in classical executive tests were explained by taking g as a covariate.•Deficits in a multitasking test remained after introducing g as a covariate.
PMCID: PMC5637303  PMID: 28800514
Spearman's g; Frontal deficits; Multitasking; Theory of mind
14.  Nonsuicidal Self-Injury Disorder: Does Criterion B Add Diagnostic Utility? 
Psychiatry research  2016;244:179-184.
The current paper evaluates Criterion B for Non-Suicidal Self-Injury Disorder, which states that non-suicidal self-injury (NSSI) must occur for at least one function. The majority of individuals who engage in NSSI report at least one function, so it is unclear if Criterion B provides diagnostic utility in individuals who already meet Criterion A (i.e., NSSI occurring on 5 or more days in the past 12 months). This paper compared individuals meeting Criterion A (threshold group) to those with 1-4 acts of NSSI in the past year (subthreshold group) in two different samples. The first sample included 217 undergraduate students, and the second sample included 1082 individuals from a behavioral health hospital, all with past-year NSSI. The majority of both samples reported at least one function of NSSI (99%). For the undergraduate sample, the number of and level of endorsement of functions were similar across threshold and subthreshold groups. For the behavioral health sample, the threshold group endorsed significantly more functions for NSSI and greater endorsement of affect regulation, self-punishment, and toughness compared to the subthreshold group. While some differences were found between NSSI groups, overall endorsement of functions for NSSI appears to be a universal characteristic regardless of NSSI frequency.
PMCID: PMC5026934  PMID: 27479110
deliberate self-harm; self-harm behavior; DSM-5; functions; criteria
15.  Wearable Devices and Mobile Technologies for Supporting Behavioral Weight Loss Among People with Serious Mental Illness 
Psychiatry research  2016;244:139-144.
Promoting physical activity is essential for addressing elevated cardiovascular risk and high obesity rates affecting people with serious mental illness. Numerous challenges interfere with exercise participation in this high-risk group including mental health symptoms, low motivation, and limited access to safe and affordable options for physical activity. Wearable devices and mobile health technologies may afford new opportunities for promoting physical activity and supporting behavioral weight loss efforts. This exploratory study examined whether daily step count measured using Fitbit wearable devices was associated with weight loss and improved fitness among individuals with serious mental illness enrolled in a 6-month lifestyle program. Participants (n=34) had a schizophrenia spectrum disorder (23.5%), major depression (50.0%), or bipolar disorder (26.5%), and wore Fitbits most of the days (M=86.2%; SD=18.4%) they were enrolled in the study. At 6-months, higher average daily step count was associated with greater weight loss (F=5.07; df=1,32; p=0.0314), but not improved fitness (F=1.92; df=1,31; p=0.176). These findings demonstrate that encouraging participants with serious mental illness enrolled in lifestyle interventions to collect more steps may contribute to greater weight loss. This suggests that wearable devices may offer a feasible and potentially effective strategy for supporting behavioral weight loss in community mental health settings.
PMCID: PMC5026936  PMID: 27479104
serious mental illness; mHealth; wearable devices; weight loss; fitness; physical activity
16.  Validation of the UCSD Performance-based Skills Assessment (UPSA) in Hispanics with and without schizophrenia 
Psychiatry research  2016;244:388-393.
The UCSD Performance-based Skills Assessment (UPSA) is a widely used measure of functional capacity with strong reliability and validity. However there is a lack of psychometric data on Hispanics. The purpose of this study was to determine the impact of acculturation and education on UPSA performance among 62 Hispanic participants with schizophrenia or schizoaffective disorder and 46 healthy comparison subjects. Functional capacity was measured using the UPSA. Acculturation was measured using the Acculturation Rating Scale for Mexican Americans (ARSMA). Independent t-tests indicated that participants with schizophrenia had significantly lower UPSA total scores and scored lower on all UPSA sub-scales relative to the comparison group. Multiple regression also indicated that education and acculturation were significant predictors of UPSA total scores. These data provide a better understanding of UPSA scores in Hispanics with and without schizophrenia, and suggest that education and acculturation adjustments may be required to improve interpretation of test results.
PMCID: PMC5026959  PMID: 27525829
Functioning; Functional Capacity; Latino; Independent; Spanish; Norms
17.  Hippocampal arterial cerebral blood volume in early psychosis 
Psychiatry research  2016;256:21-25.
Recent studies of patients in the early stage of psychosis have revealed increased cerebral blood volume (CBV) in specific subfields of the anterior hippocampus. These studies required injection of a contrast agent to measure steady state CBV. Here we used a novel, non-invasive method, inflow-based-vascular-space-occupancy with dynamic subtraction (iVASO-DS), to measure the arterial component of CBV (aCBV) in a single slice of the hippocampus. Based on evidence from contrast-enhanced CBV studies, we hypothesized increased aCBV in the anterior hippocampus in early psychosis. We used 3T MRI to generate iVASO-derived aCBV maps in 17 medicated patients (average duration of illness = 7.6 months) and 25 matched controls. We did not find hemispheric or regional group differences in hippocampal aCBV. The limited spatial resolution of the iVASO-DS method did not allow us to test for aCBV differences in specific subfields of the hippocampus. Future studies should investigate venous and arterial CBV changes in the hippocampus of early psychosis patients.
PMCID: PMC5064837  PMID: 27644028
hippocampus; inflow-based-vascular-space-occupancy; iVASO; arterial cerebral blood volume; aCBV; early psychosis
18.  Examining the Role of Self-Discrepancy and Self-Directed Style in Bulimia Nervosa 
Psychiatry research  2016;244:294-299.
Two of the primary components within Integrative Cognitive Affective Therapy (ICAT) are self-discrepancy and self-directed style. Self-discrepancy includes both actual:ideal (discrepancy between oneself and who one wishes they were) and actual:ought (discrepancy between oneself and who one believes they ought to be). Self-directed style in ICAT refers to a variety of behaviors emitted by a person toward the self including self-blaming and self-affirming. This study explored main effects and interactions between self-discrepancy and self-directed style in relation to global eating disorder (ED) psychopathology, depressive symptoms, and anxiety. Eighty treatment-seeking adults from the Midwest with BN or subthreshold BN completed interviews and self-report measures. Self-affirm and self-blame were associated with ED psychopathology, depressive symptoms, and anxiety. Actual:ideal discrepancy was related to anxiety and actual:ought discrepancy was related to anxiety and depression. Interactions were found between self-affirm and actual:ought discrepancy as well as self-blame and actual:ought discrepancy and depressive symptoms. High actual:ought was related to increased depressive symptoms regardless of levels of self-affirm and self-blame. Effect sizes for models were medium-to-large with anxiety models demonstrating the largest effects. This study provides further evidence supporting the ICAT model and treatment, which targets self-discrepancies, self-directed styles, and related emotional states.
PMCID: PMC5293165  PMID: 27512918
bulimia nervosa; self-discrepancy; self-directed style; integrative cognitive affective therapy
19.  Altered neurotransmitter metabolism in adolescents with high-functioning autism 
Psychiatry research  2016;256:44-49.
Previous studies have suggested that alterations in excitatory/inhibitory neurotransmitters might play a crucial role in autism spectrum disorder (ASD). Proton magnetic resonance spectroscopy (1H-MRS) can provide valuable information about abnormal brain metabolism and neurotransmitter concentrations. However, few 1H-MRS studies have been published on the imbalance of the two most abundant neurotransmitters in ASD: glutamate (Glu) and gamma-aminobutyric acid (GABA). Moreover, to our knowledge none of these published studies is performed with a study population consisting purely of high-functioning autism (HFA) adolescents. Selecting only individuals with HFA eliminates factors possibly related to intellectual impairment instead of ASD. This study aims to assess Glu and GABA neurotransmitter concentrations in HFA. Occipital concentrations of Glu and GABA plus macromolecules (GABA+) were obtained using 1H-MRS relative to creatine (Cr) in adolescents with HFA (n=15 and n=13 respectively) and a healthy control group (n=17). Multiple linear regression revealed significantly higher Glu/Cr and lower GABA+/Glu concentrations in the HFA group compared to the controls. These results imply that imbalanced neurotransmitter levels of excitation and inhibition are associated with HFA in adolescents.
PMCID: PMC5385138  PMID: 27685800
Magnetic resonance spectroscopy; Glutamate; Gamma-aminobutyric acid
20.  Does Body Mass Index Moderate the Association between Posttraumatic Stress Disorder Symptoms and Suicidal Ideation in Iraq/Afghanistan Veterans? 
Psychiatry research  2016;244:123-129.
Suicide, PTSD, and obesity co-occur at high rates among returning veterans, yet limited research exists regarding the relationship among these variables. Self-report and diagnostic interview data from a longitudinal study of Iraq and Afghanistan veterans (N = 130) enrolled in VA healthcare examined these inter-relations. As hypothesized, body mass index (BMI) significantly moderated the association between PTSD and suicidal ideation such that the association between PTSD and suicidal ideation was strongest among individuals with a high BMI. Programs that focus on health promotion, trauma treatment, and weight management should continue to monitor suicide risk.
PMCID: PMC5556387  PMID: 27479102
21.  Intact error monitoring in combat Veterans with post-traumatic stress disorder 
Psychiatry research  2015;234(2):227-238.
The error-related negativity (ERN) is a neuroelectric signature of performance monitoring during speeded response time tasks. Previous studies indicate that individuals with anxiety disorders show ERN enhancements that correlate with the degree of clinical symptomology. Less is known about the error monitoring system in post-traumatic stress disorder (PTSD). PTSD is characterized by impairments in the regulation of fear and other emotional responses, as well as deficits in maintaining cognitive control. Here, combat Veterans with PTSD were compared to control Veterans in two different versions of the flanker task (n=13 or 14 per group). Replicating and extending previous findings, PTSD patients showed an intact ERN in both experiments. In addition, task performance and error compensation behavior were intact. Finally, ERN amplitude showed no relationship with self-reported PTSD, depression, or post-concussive symptoms. These results suggest that error monitoring represents a relative strength in PTSD that can dissociate from cognitive control functions that are impaired, such as response inhibition and sustained attention. A healthy awareness of errors in external actions could be leveraged to improve interoceptive awareness of emotional state. The results could have positive implications for PTSD treatments that rely on self-monitoring abilities, such as neurofeedback and mindfulness training.
PMCID: PMC5645022  PMID: 26481979
Error-Related Negativity; Performance Monitoring; Self-Monitoring; Mild Traumatic Brain Injury; Anterior Cingulate Cortex; Cognitive Control; Anxiety
22.  Comparison of Brain Activation Patterns during Executive Function Tasks in Hoarding Disorder and Non-Hoarding OCD 
Psychiatry research  2016;255:50-59.
We examined differences in regional brain activation during tests of executive function in individuals with Hoarding Disorder (HD), Obsessive Compulsive Disorder (OCD), and healthy controls (HC) using functional magnetic resonance imaging (fMRI). Participants completed computerized versions of the Stroop and Go/No-Go task. We found that during the conflict monitoring and response inhibition condition in the Go/No-Go task, individuals with HD had significantly greater activity than controls in the anterior cingulate cortex (ACC) and right dorsolateral prefrontal cortex (DLPFC). HD also exhibited significantly greater right DLPFC activity than OCD. We also observed significant differences in activity between HD and HC and between HD and OCD in regions (ACC, anterior insula, orbitofrontal cortex (OFC), and striatum) involved in evaluating stimulus-response-reward associations, or the personal and task-relevant value of stimuli and behavioral responses to stimuli. These results support the hypothesis that individuals with HD have difficulty deciding on the value or task relevance of stimuli, and may perceive an abnormally high risk of negative feedback for difficult or erroneous cognitive behavior.
PMCID: PMC5014569  PMID: 27522332
Neuroimaging; fMRI; Stroop; Go/No-go; conflict monitoring; response inhibition; hoarding disorder
23.  Delusions in First-Episode Psychosis: Principal Component Analysis of Twelve Types of Delusions and Demographic and Clinical Correlates of Resulting Domains 
Psychiatry research  2016;243:5-13.
Although delusions represent one of the core symptoms of psychotic disorders, it is remarkable that few studies have investigated distinct delusional themes. We analyzed data from a large sample of first-episode psychosis patients (n=245) to understand relations between delusion types and demographic and clinical correlates. First, we conducted a principal component analysis (PCA) of the 12 delusion items within the Scale for the Assessment of Positive Symptoms (SAPS). Then, using the domains derived via PCA, we tested a priori and exploratory hypotheses related to delusional content. PCA revealed five distinct components: Delusions of Influence, Grandiose/Religious Delusions, Paranoid Delusions, Negative Affect Delusions (jealousy, and sin or guilt), and Somatic Delusions. The most prevalent type of delusion was Paranoid Delusions, and such delusions were more common at older ages at onset of psychosis. The level of Delusions of Influence was correlated with the severity of hallucinations and negative symptoms. We ascertained a general relationship between different childhood adversities and delusional themes, and a specific relationship between Somatic Delusions and childhood neglect. Moreover, we found higher scores on Delusions of Influence and Negative Affect Delusions among cannabis and stimulant users. Our results support considering delusions as varied experiences with varying prevalences and correlates.
PMCID: PMC5014642  PMID: 27344587
Childhood adversities; Delusions; Depression; Drugs of abuse; Hallucinations; Paranoia; Persecutory delusions
24.  Maternal T. gondii, offspring bipolar disorder and neurocognition 
Psychiatry research  2016;243:382-389.
Prenatal exposure to maternal Toxoplasma gondii (T. gondii) IgG antibody titer has been associated previously with an increased risk of offspring schizophrenia (SZ) and cognitive impairment. We examined maternal T. gondii, offspring bipolar disorder (BP) and childhood cognition using a population-based birth cohort. Maternal sera, drawn in the third trimester, were analyzed for T. gondii IgG antibody titer, and offspring cognition at ages 5 and 9–11 was measured with the Peabody Picture Vocabulary Test (PPVT) and the Raven Matrices (Raven). Raw scores were standardized and the ages combined. Potential cases with BP from the cohort were identified by database linkages. This protocol identified 85 cases who were matched 1:2 to controls. Maternal T. gondii IgG was not associated with the risk of BP in offspring. Neither moderate [HR = 1.43 (CI: 0.49, 4.17)] nor high IgG titer [HR = 1.6 [CI: 0.74, 3.48)] were associated with offspring BP. Associations were not observed between maternal T. gondii and BP with psychotic features or BP type 1. In addition, maternal T. gondii was not associated with childhood cognition. Our study suggests that T. gondii may be specific to SZ among major psychotic disorders, though further studies with larger sample sizes are required.
PMCID: PMC5014658  PMID: 27449007
Psychotic disorders; Toxoplasma gondii; Neurodevelopment; Cognition; Birth cohort; Raven Matrices; PPVT
25.  Negative affect predicts social functioning across schizophrenia and bipolar disorder: Findings from an integrated data analysis 
Psychiatry research  2016;243:198-206.
Most people with a serious mental illness experience significant functional impairment despite ongoing pharmacological treatment. Thus, in order to improve outcomes, a better understanding of functional predictors is needed. This study examined negative affect, a construct comprised of negative emotional experience, as a predictor of social functioning across serious mental illnesses. One hundred twenty-seven participants with schizophrenia, 113 with schizoaffective disorder, 22 with psychotic disorder not otherwise specified, 58 with bipolar disorder, and 84 healthy controls (N=404) completed self-report negative affect measures. Elevated levels of negative affect were observed in clinical participants compared with healthy controls. For both clinical and healthy control participants, negative affect measures were significantly correlated with social functioning, and consistently explained significant amounts of variance in functioning. For clinical participants, this relationship persisted even after accounting for cognition and positive/negative symptoms. The findings suggest that negative affect is a strong predictor of outcome across these populations and treatment of serious mental illnesses should target elevated negative affect in addition to cognition and positive/negative symptoms.
PMCID: PMC5014676  PMID: 27416540
Emotion; Serious mental illness; Transdiagnostic; Cognition; Social cognition; Positive symptoms; Negative symptoms

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