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Dive into the research topics where Alan I. Green is active.

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Featured researches published by Alan I. Green.


Proceedings of the National Academy of Sciences of the United States of America | 2009

Hyperactivity and hyperconnectivity of the default network in schizophrenia and in first-degree relatives of persons with schizophrenia

Susan Whitfield-Gabrieli; Heidi W. Thermenos; Snezana Milanovic; Ming T. Tsuang; Stephen V. Faraone; Robert W. McCarley; Martha Elizabeth Shenton; Alan I. Green; Alfonso Nieto-Castanon; Peter S. LaViolette; Joanne Wojcik; John D. E. Gabrieli; Larry J. Seidman

We examined the status of the neural network mediating the default mode of brain function, which typically exhibits greater activation during rest than during task, in patients in the early phase of schizophrenia and in young first-degree relatives of persons with schizophrenia. During functional MRI, patients, relatives, and controls alternated between rest and performance of working memory (WM) tasks. As expected, controls exhibited task-related suppression of activation in the default network, including medial prefrontal cortex (MPFC) and posterior cingulate cortex/precuneus. Patients and relatives exhibited significantly reduced task-related suppression in MPFC, and these reductions remained after controlling for performance. Increased task-related MPFC suppression correlated with better WM performance in patients and relatives and with less psychopathology in all 3 groups. For WM task performance, patients and relatives had greater activation in right dorsolateral prefrontal cortex (DLPFC) than controls. During rest and task, patients and relatives exhibited abnormally high functional connectivity within the default network. The magnitudes of default network connectivity during rest and task correlated with psychopathology in the patients. Further, during both rest and task, patients exhibited reduced anticorrelations between MPFC and DLPFC, a region that was hyperactivated by patients and relatives during WM performance. Among patients, the magnitude of MPFC task suppression negatively correlated with default connectivity, suggesting an association between the hyperactivation and hyperconnectivity in schizophrenia. Hyperactivation (reduced task-related suppression) of default regions and hyperconnectivity of the default network may contribute to disturbances of thought in schizophrenia and risk for the illness.


Journal of Nervous and Mental Disease | 1991

EFFECT OF PERSONALITY DISORDERS ON OUTCOME OF TREATMENT

James Reich; Alan I. Green

Although many clinicians have long believed that personality pathology may interfere with the effectiveness of treatment of axis I disorders, until recently there were no empirical studies on the subject. This report reviews the recent literature with regard to the following questions: a) Does personality pathology predict negative outcome of treatment for axis I disorders? b) If so, are there specific personality traits or disorders that account for such a negative outcome? The literature review reveals a robust finding that patients with personality pathology have a poorer response to treatment of axis I disorders than those without such pathology. Specific axis I disorders reported on include DSM-III major depression, panic disorder, and obsessive-compulsive disorder. Both inpatients and outpatients have been studied. There is too little literature to determine whether certain pathological personality traits are especially important, but there is enough to provide methodological guidance for future studies. Such studies should use standardized measures of personality and outcome, should match personality and nonpersonality groups on severity of the axis I disorder, and should be certain that axis I diagnoses are not confounded by axis II symptoms.


Schizophrenia Research | 1997

Differential relationships between positive and negative symptoms and neuropsychological deficits in schizophrenia

Ileana Berman; Barbara Viegner; Amalia Merson; Edward R. Allan; Demetra Pappas; Alan I. Green

UNLABELLED This study assessed the relationships between positive and negative clinical symptoms and specific neuropsychological deficits in a group of stable schizophrenic patients. METHOD Thirty patients were assessed using the Positive and Negative Syndrome Scale (PANSS) for schizophrenia and a battery of cognitive tests. The PANSS assessments were done by a group of raters blind to the results of cognitive tests, while the cognitive tests were conducted by a different group of raters who remained blind to the PANSS scores. RESULTS We found that, although positive and negative symptoms showed a trend toward direct correlation with each other, they correlated with distinct cognitive deficits. Patients with higher negative scores had more perseverative responses, perservative errors, and completed fewer categories on the Wisconsin Card Sorting Test; they also experienced more difficulties on trail making and verbal fluency tests. On the other hand, positive symptoms were associated with poor performance on the Digit Span, particularly the Digit Span Forward. CONCLUSIONS Our findings are in agreement with previous reports that negative symptoms may be associated with poor performance on cognitive tests reflecting particularly frontal function. Positive symptoms, on the other hand, seem to be associated with poor attention, specifically of auditory type, and thus, possibly with dysfunction within the more widespread neural networks underlying attention. Our findings support the hypothesis that positive and negative symptoms may be associated with distinct neuropsychological deficits and thus with distinct neurological substrates and point to the need to address both positive and negative dimensions when studying schizophrenia.


Schizophrenia Research | 2004

First episode schizophrenia-related psychosis and substance use disorders: acute response to olanzapine and haloperidol.

Alan I. Green; Mauricio Tohen; Robert M. Hamer; Stephen M. Strakowski; Jeffrey A. Lieberman; Ira D. Glick; W. Scott Clark

BACKGROUND Co-occurring substance use disorders, mostly involving alcohol, cannabis or cocaine, occur commonly in patients with schizophrenia and are associated with increased morbidity and mortality. Available but limited data suggest that substance use disorders (especially cannabis use disorders) may also be common in first-episode patients and appear linked to a poor outcome in these patients. Strategies to curtail substance use form an important dimension of the treatment program for both first-episode and chronic patients. We report on rates of co-occurring substance use disorders in patients within their first episode of schizophrenia-related psychosis from a multicenter, international treatment trial of olanzapine vs. haloperidol. METHODS The study involved 262 patients (of 263 who were randomized and who returned for a post-randomization evaluation) within their first episode of psychosis (schizophrenia, schizoaffective disorder or schizophreniform disorder) recruited from 14 academic medical centers in North America and Western Europe. Patients with a history of substance dependence within 1 month prior to entry were excluded. RESULTS Of this sample, 97 (37%) had a lifetime diagnosis of substance use disorder (SUD); of these 74 (28% of the total) had a lifetime cannabis use disorder (CUD) and 54 (21%) had a lifetime diagnosis of alcohol use disorder (AUD). Patients with SUD were more likely to be men. Those with CUD had a lower age of onset than those without. Patients with SUD had more positive symptoms and fewer negative symptoms than those without SUD, and they had a longer duration of untreated psychosis. The 12-week response data indicated that 27% of patients with SUD were responders compared to 35% of those without SUD. Patients with AUD were less likely to respond to olanzapine than those without AUD. DISCUSSION These data suggest that first-episode patients are quite likely to have comorbid substance use disorders, and that the presence of these disorders may negatively influence response to antipsychotic medications, both typical and atypical antipsychotics, over the first 12 weeks of treatment.


Schizophrenia Research | 2006

Predictors of antipsychotic medication adherence in patients recovering from a first psychotic episode.

Diana O. Perkins; Jacqueline L. Johnson; Robert M. Hamer; Robert B. Zipursky; Richard S.E. Keefe; Franca Centorrhino; Alan I. Green; Ira B. Glick; René S. Kahn; Tonmoy Sharma; Mauricio Tohen; Joseph P. McEvoy; Peter J. Weiden; Jeffrey A. Lieberman; Charles B. Nemeroff; Bruce M. Cohen; Franca Centhorrino; Gary D. Tollefson; T.M. Sanger; John M. Kuldau; Anthony J. Rothschild; Jayendra K. Patel; Raquel E. Gur; Zafiris J. Daskalakis; Stephen M. Strakowski; John De Quardo; R.S. Kahn; Robin M. Murray

BACKGROUND Many patients recovering from a first psychotic episode will discontinue medication against medical advice, even before a 1-year treatment course is completed. Factors associated with treatment adherence in patients with chronic schizophrenia include beliefs about severity of illness and need for treatment, treatment with typical versus atypical antipsychotic and medication side effects. METHOD In this 2-year prospective study of 254 patients recovering from a first episode of schizophrenia, schizophreniform, or schizoaffective disorder we examined the relationship between antipsychotic medication non-adherence and patient beliefs about: need for treatment, antipsychotic medication benefits, and negative aspects of antipsychotic medication treatment. We also examined the relationship between medication non-adherence and treatment with either haloperidol or olanzapine, and objective measures of symptom response and side effects. RESULTS The likelihood of becoming medication non-adherent for 1 week or longer was greater in subjects whose belief in need for treatment was less (HR=1.75, 95% CI 1.16, 2.65, p=0.0077) or who believed medications were of low benefit (HR=2.88, 95 CI 1.79-4.65, p<0.0001). Subjects randomized to haloperidol were more likely to become medication non-adherent for >or=1 week than subjects randomized to olanzapine (HR-1.51, 95% CI 1.01, 2.27, p=0.045). CONCLUSION Beliefs about need for treatment and the benefits of antipsychotic medication may be intervention targets to improve likelihood of long-term medication adherence in patients recovering from a first episode of schizophrenia, schizoaffective, or schizophreniform disorder.


Journal of Nervous and Mental Disease | 1998

Obsessions and compulsions as a distinct cluster of symptoms in schizophrenia : A neuropsychological study

Ileana Berman; Amalia Merson; Barbara Viegner; Miklos F. Losonczy; Demetra Pappas; Alan I. Green

Using neurocognitive testing, the present study assessed whether obsessions and compulsions could represent a distinct cluster of symptoms in schizophrenia. We formulated our hypothesis based on data from nonschizophrenic patients, expecting to find that schizophrenic patients with obsessive-compulsive (OC) symptoms would experience more difficulties in the same cognitive areas as nonschizophrenic patients with obsessive-compulsive disorder (OCD). Patients had separate psychiatric and cognitive evaluations. The OC and non-OC schizophrenic subjects did not differ significantly on the positive and negative symptom scores. However, compared with non-OC schizophrenic patients, those with OC symptoms performed worse on cognitive areas thought to be impaired (i.e., visual-spatial skills, delayed nonverbal memory, and cognitive shifting abilities). In addition, the severity of OC scores correlated with poor performance in these areas of cognition. Our results support our hypothesis, specifically that OC symptoms may constitute a distinct cluster separate from psychosis in schizophrenia and raise the possibility of a distinct subtype of schizophrenia. The theoretical and clinical implications of these findings are discussed.


Schizophrenia Research | 2003

Alcohol and cannabis use in schizophrenia: effects of clozapine vs. risperidone

Alan I. Green; Ellen S. Burgess; Ree Dawson; Suzannah V. Zimmet; Rael D. Strous

BACKGROUND Alcohol and cannabis use disorders worsen the course of schizophrenia. While the typical antipsychotics are of limited value in controlling substance use in schizophrenic patients, previous studies suggest that the novel antipsychotic clozapine (CLOZ) may decrease their substance use. We describe a retrospective study of the effects of the novel antipsychotics risperidone (RISP) and clozapine on alcohol and cannabis use in patients with schizophrenia or schizoaffective disorder and comorbid alcohol and/or cannabis use disorder. METHOD This study involved retrospective assessment of abstinence (cessation of alcohol and cannabis use) in 41 patients treated with either risperidone (n=8) or clozapine (n=33) for at least 1 year. In 32 of these 41 patients, information was available on whether abstinence occurred during the 1-year period. RESULTS Abstinence rates were significantly higher in patients treated with clozapine than in those treated with risperidone (54% vs. 13%, p=0.05). The nine patients treated for at least 1 year, but excluded from the analysis because time of cessation of use was not known, had all stopped alcohol/cannabis use during clozapine treatment. DISCUSSION While the limitations of this retrospective study must be recognized, the data suggest that comorbid patients treated with clozapine are more likely to abstain from alcohol and cannabis use than are those treated with risperidone. Further prospective studies will be required to confirm these intriguing results.


Schizophrenia Research | 2006

Olanzapine and haloperidol in first episode psychosis: Two-year data ☆

Alan I. Green; Jeffrey A. Lieberman; Robert M. Hamer; Ira D. Glick; Raquel E. Gur; René S. Kahn; Joseph P. McEvoy; Diana O. Perkins; Anthony J. Rothschild; T. Sharma; Mauricio Tohen; Sandra Woolson; Robert B. Zipursky

Few studies have assessed the comparative efficacy and safety of atypical and typical antipsychotic medications in patients within their first episode of psychosis. This study examined the effectiveness of the atypical antipsychotic olanzapine and the typical antipsychotic haloperidol in patients experiencing their first episode of a schizophrenia-related psychotic disorder over a 2-year treatment period. Two hundred and sixty-three patients were randomized to olanzapine or haloperidol in a doubleblind, multisite, international 2-year study. Clinical symptoms and side effects were assessed at baseline and longitudinally following randomization for the duration of the study. Olanzapine and haloperidol treatment were both associated with substantial and comparable reductions in symptom severity (the primary outcome measure) over the course of the study. However, the treatment groups differed on two secondary efficacy measures. Patients were less likely to discontinue treatment with olanzapine than with haloperidol: mean time (in days) in the study was significantly greater for those treated with olanzapine compared to haloperidol (322.09 vs. 230.38, p<0.0085). Moreover, remission rates were greater in patients treated with olanzapine as compared to those treated with haloperidol (57.25% vs. 43.94%, p<0.036). While extrapyramidal side effects were greater in those treated with haloperidol, weight gain, cholesterol level and liver function values were greater in patients treated with olanzapine. The data from this study suggest some clinical benefits for olanzapine as compared to haloperidol in first episode patients, which must be weighed against those adverse effects that are more likely with olanzapine.


Psychiatric Clinics of North America | 2003

Detection and management of comorbidity in patients with schizophrenia

Alan I. Green; Carla M. Canuso; Mark J. Brenner; Joanne Wojcik

Approximately half of patients with schizophrenia have at least one comorbid psychiatric or medical condition, worsening prognosis and contributing to the high rate of morbidity and mortality. Depression is associated with suicide, the leading cause of premature death in patients with schizophrenia; obsessive-compulsive symptoms may worsen prognosis; alcohol and substance use disorders are associated with a poor outcome; and comorbid medical conditions, including cardiac and pulmonary disease, infectious diseases, diabetes, hyperlipidemia, hypogonadism, and osteoporosis, are often underrecognized and undertreated. The new generation of antipsychotic medications has improved the potential outcome of patients with schizophrenia. Providing optimal treatment for patients and fully realizing the potential of these new agents require focused attention on detection, recognition, and treatment of comorbid psychiatric and medical conditions in patients with schizophrenia.


International Review of Neurobiology | 1970

Uptake and Subcellular Localization of Neurotransmitters in the Brain

Solomon H. Snyder; Michael J. Kuhar; Alan I. Green; Joseph T. Coyle; Edward G. Shaskan

Publisher Summary Nerve terminals in the brain possess specialized uptake mechanisms for a variety of putative neurotransmitters, such as dopamine (DA), norepinephrine (NE), serotonin, γ-aminobutyric acid (GABA) and, possibly, for glutamic acid and glycine. This chapter describes the specific uptake mechanisms for several putative neurotransmitters in the brain and their use in labeling and separating synaptosomes storing different putative neurotransmitters. The chapter proposes to use these uptake systems for labeling the endogenous transmitter pools with exogenous, radioactive neurotransmitters, labeling one class of synaptosomes with 3 H-transmitter and another with 14 C-transmitter. Kinetic studies elucidate the optimal conditions for nerve endings in brain slices or in isolated, pinched-off form (synaptosomes) to accumulate selectively their specific transmitter. The synaptosomal populations are separated with density gradient centrifugal procedures in the same brain region storing different transmitters or in different brain region storing the same transmitter. The electron microscopic studies reveal specific morphological features for the varying synaptosomal populations.

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Mauricio Tohen

University of New Mexico

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Diana O. Perkins

University of North Carolina at Chapel Hill

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Raquel E. Gur

University of Pennsylvania

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