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Michael F Green

Publications and source records attributed to Michael F Green.

At least 37 records · Page 2Linked to original sources
PubMed2005

Cross-ethnic differences in perception of emotion in schizophrenia.

BACKGROUND: The purpose of this study was to examine cross-ethnic differences in Perception of Emotion (POE) in schizophrenia. POE is an emerging construct in schizophrenia and involves the recognition and accurate identification of emotion in the facial and vocal expression of others. It has been implicated as relevant to instrumental functioning in schizophrenia, as well as a potential core deficit or marker for the disorder. Studies have shown the role of culture in shaping the expression and perception of emotion in non-clinical samples. It was hypothesized that ethnic minorities would have lower POE scores than Caucasians, and that the differences on POE would remain significant after controlling for neurocognition. METHOD: Individuals, 131, diagnosed with schizophrenia or schizoaffective disorder participated in the study. There were 59 Euro-American Caucasian, 56 were African-American, and 16 were Latino. Neurocognition was measured as a standardized sum of five neuropsychological measures. Perception of Emotion was measured with facial and voice recognition tasks. RESULTS: Both Latinos and African-Americans scored lower on POE than Caucasians. The cross-ethnic differences on POE remained significant after controlling for neurocognition and overall symptom level. Post hoc analyses showed some support for the predictive validity of the POE measure across cultural contexts. CONCLUSIONS: These results suggest that POE in schizophrenia is influenced by ethnicity, and that the ethno-cultural mechanisms influencing POE transcend the shared variation of POE and neurocognition. These results have implications for theories of cross-cultural emotion recognition, measurement bias in POE research, and for the place of culture in the study of POE in schizophrenia.

Adult↗
PubMed2005

Forward and backward visual masking in unaffected siblings of schizophrenic patients.

BACKGROUND: Visual masking tasks assess the earliest stages of visual processing. This study examined visual masking performance for forward and backward masking tasks in siblings of schizophrenic patients and healthy comparison subjects. METHODS: A staircase method was used to ensure that unmasked target identification was equivalent across subjects to eliminate differences due to discrimination of simple perceptual inputs. Four computerized visual masking tasks were administered to 43 siblings of patients and 42 normal comparison subjects. The tasks included: 1) locating a target; 2) identifying a target with a high-energy mask; 3) identifying a target with a low-energy mask; and 4) a paracontrast/metacontrast procedure with nonoverlapping target and mask. RESULTS: Across masking conditions, there was a significant group by forward/backward interaction, meaning that siblings showed a larger difference from control subjects in backward versus forward masking. This group difference was more pronounced in the location condition. CONCLUSIONS: These results support the theory that visual masking procedures may be indicators of vulnerability to schizophrenia. The pattern of findings in this report (larger group differences on backward versus forward masking and on the location condition) suggests that the activity of transient visual channels may be particularly linked to vulnerability.

Adult↗
PubMed2005

Social cognition in schizophrenia: recommendations from the measurement and treatment research to improve cognition in schizophrenia new approaches conference.

This article summarizes the discussion from a breakout group at the National Institute of Mental Health-Measurement and Treatment Research to Improve Cognition in Schizophrenia New Approaches Conference on social cognition in schizophrenia. During this discussion, the reasons for the recent growth of research on social cognition in schizophrenia were examined. The discussion group established consensus on several points, including the importance of viewing social cognition from interdisciplinary perspectives (including outcomes research, social psychology, cognitive psychology, cognitive neuroscience, and animal models) and the need for clearer definition of terms. There was also general agreement that social cognition is a valuable construct for understanding the nature and disability of schizophrenia. One of the objectives of this group was to generate recommendations for subsequent human and animal studies, and these research agendas are summarized in this report.

Animals↗
PubMed2005

Biosocial pathways to functional outcome in schizophrenia.

UNLABELLED: Biosocial models are preeminent in the study of schizophrenia, yet there has been little empirical testing of these models. OBJECTIVE: This study provided the first test of a biosocial causal model of functional outcome in schizophrenia, using neurocognition, social cognition, social competence and social support as predictors of both global and specific domains of functional outcome. METHOD: The design used baseline variables to predict both concurrent functional status and prospective 12-month functional outcome. Subjects were recruited upon admission to outpatient community-based psychosocial rehabilitation programs shown in previous studies to be effective in improving functional outcomes. 139 individuals diagnosed with schizophrenia or schizoaffective disorder participated in the study; 100 participants completed the 12-month assessments. Face-to-face interviews assessed neurocognitive functioning (with five neuropsychological measures), social cognition (as perception of emotion), social competence, social support, and functional outcome which consisted of items covering the domains of social, independent living, and work functioning. RESULTS: Path analysis modeling showed that the proposed biosocial models had strong fit with the data, for both concurrent and 12-month global functional outcomes, with fit indices ranging from .95 to .98. The model explained 21% of the variance in concurrent global functional outcome, and 14% of the variance in 12-month prospective outcome. CONCLUSIONS: The support for this model was strong, and it has implications for understanding the causal factors related to functional outcome, as well as for intervention strategies for improving functional outcomes in schizophrenia.

Adaptation, Psychological↗
PubMed2005

The FOCIS international survey on psychiatrists' opinions on cognition in schizophrenia.

BACKGROUND: The goal of this project was to develop an interview to evaluate psychiatrists' views on the nature of cognitive dysfunction in schizophrenia, its importance as a potential treatment target, and its relative importance as a treatment target across different phases of schizophrenia. MATERIALS AND METHODS: A survey (available in paper or on-line) consisting of 27 questions, was developed by the Focus on Cognition in Schizophrenia (FOCIS) group, and distributed in a single wave mailing to 63,295 psychiatrists in 21 countries worldwide. RESULTS: The overall response rate was 4.7% (n=2975). The surveyed psychiatrists perceived cognition as a high treatment priority in stabilized schizophrenia patients, but less so for first episode or acute schizophrenia patients. The potential of atypical antipsychotics to improve cognitive dysfunction in schizophrenia was identified by 81% of the respondent psychiatrists. CONCLUSIONS: Cognitive deficits in people with schizophrenia are seen by clinical psychiatrists as relevant to treatment and rehabilitation plans. They were, however, regarded as a higher treatment priority in stabilized chronic rather than in first episode patients. The results suggest clinical psychiatrists need additional education regarding the nature of cognitive dysfunction in schizophrenia and its importance for psychosocial rehabilitation and community re-entry.

Attitude of Health Personnel↗
PubMed2005

Sensorimotor gating, orienting and social perception in schizophrenia.

Basic neurocognition and social cognition appear to influence the social impairments of persons with schizophrenia. This study examined relationships between two very basic automatic processes (i.e., sensorimotor gating and orienting) and social perception in schizophrenic patients. Thirty outpatients with schizophrenia completed psychophysiological measures of sensorimotor gating (prepulse inhibition, PPI), orienting (prepulse facilitation, PPF), and social perception (the Half Profile of Nonverbal Sensitivity, Half PONS). A median split was used to divide patients into poor and good gaters and poor and good orienters. Analyses revealed that patients with good PPI scored significantly higher on the Half PONS than patients with poor PPI. PPI showed a significant correlation (r=-0.54) with Half PONS performance, indicating that schizophrenia patients who were better able to gate out competing stimuli (i.e., less startle) were also better at detecting relevant social cues. Orienting (PPF) and social perception were not related. This study is the first to our knowledge to demonstrate an association between sensorimotor gating and social perception. The findings are consistent with other studies that have demonstrated relationships between basic neurocognition and social cognition. By showing a link between sensorimotor gating and social perception, this study supports social cognition's potential role as a mediator of the relationship between neurocognition and social functioning in schizophrenia.

Adult↗
PubMed2005

Learning potential and the prediction of work skill acquisition in schizophrenia.

This study examined whether a measure of learning potential could predict work skill acquisition in schizophrenia beyond the prediction offered by a single administration assessment. Fifty-seven outpatients with schizophrenia or schizoaffective disorder completed a test-train-test version of the Wisconsin Card Sorting Test as a measure of their learning potential. The outpatients were randomly assigned to training by errorless learning or conventional instruction on two work skills (index card filing and toilet tank assembly). Work skills were assessed both immediately and 3 months after training. Generally, patients with high learning potential performed better on the work skill tasks. Learning potential explained an additional 15 percent of variance beyond single administration assessment in participants' accuracy immediately after work skill training and an additional 13 percent of variance in participants' accuracy 3 months after training. These findings indicate that measures of learning potential contribute to the prediction of work skill acquisition, going beyond the predictive power of single administration assessments.

Adult↗
PubMed2005

A summary of the FDA-NIMH-MATRICS workshop on clinical trial design for neurocognitive drugs for schizophrenia.

OBJECTIVE: On April 23, 2004, a joint meeting of the FDA, NIMH, MATRICS investigators, and experts from academia and the pharmaceutical industry was convened to develop guidelines for the design of clinical trials of cognitive-enhancing drugs for neurocognitive impairments in patients with schizophrenia. METHOD: Experts were asked to address specific questions relating to clinical trial design of adjunctive/co-treatment and broad spectrum agents. At the workshop, experts reviewed relevant evidence before offering the discussion panel proposed guidelines for a given subset of questions. The discussion panel, which consisted of presenters and representatives from FDA, NIMH, academia, and industry, deliberated to reach consensus on suggested guidelines. When evidence was insufficient, suggested guidelines represent the opinion of a cross-section of the presenters and discussion panel. RESULTS: Guidelines were developed for inclusion criteria, the use of co-primary outcome measures, and statistical approaches for study design. Consensus was achieved regarding diagnostic and concomitant medication inclusion criteria and on the use of cognitive screening measures. A key guideline was to limit the trial to patients in the residual phase of their illness, who have a predefined level of positive, negative, and affective symptoms. The most difficult issues were the feasibility of including a co-primary measure of functional improvement and the choice of comparator agent for a trial of a broad spectrum agent (with antipsychotic and cognitive-enhancing effects). CONCLUSIONS: The suggested guidelines represent reasonable starting points for trial design of cognitive-enhancing drugs, with the understanding that new data, subsequent findings, or other methodological considerations may lead to future modifications.

Antipsychotic Agents↗
PubMed2005

Regional brain activity associated with visual backward masking.

In visual backward masking, the visibility of a briefly presented visual target is disrupted by a mask that is presented shortly thereafter. The goal of the current study was to identify regions in the human cortex that may provide the neural basis of visual masking. We searched for areas whose activity correlated with perception as we systematically varied the strength of masking. A total of 13 subjects performed a backward masking task during functional magnetic resonance imaging. Target and mask were presented at three delay intervals (34, 68, and 102 msec) and behavioral measures confirmed that the targets were more visible at longer masking intervals. Two sets of regions of interest were identified: Distinct regions in the visual cortex (V1/V2, LO, hMT+) were segregated using scans to localize visual processing drawn from the existing literature. Additional cortical regions were selected in a data-driven approach based on their activity during the backward masking task. For each set, we determined the regions whose magnitude of activation increased at longer masking intervals. Nine of the subjects provided valid behavioral performance data on the visual masking task and imaging data from these subjects were used for subsequent analysis. The scans of visual processing areas identified four regions, including: early visual areas (V1 and V2), the motion-sensitive regions in the lateral occipital (LO) lobe (hMT+), and two components (dorsal and ventral) of the object-sensitive region, LO. Of these, the ventral and dorsal LO regions were sensitive to the strength of the mask. For the data-driven approach, six regions were identified on the basis of a difference map in which all masking intervals were contrasted with rest. These included the inferior parietal, anterior cingulate, precentral, insula, thalamic, and occipital areas. The predicted effects of more activity with weaker masking were seen in the thalamus, inferior parietal, and anterior cingulate. This study isolated three types of visual processing areas. The first included regions that subserve key stages of vision (including object and motion processing). The second type responded to the presentation of brief ly presented visual stimuli, regardless of masking interval. The third type (selected from the first two) included regions sensitive to the interval between the target and mask. These latter regions (including ventral LO, inferior parietal, anterior cingulate, and thalamus) may form the neural substrate of backward masking.

Adult↗
PubMed2005

Event-related gamma activity in schizophrenia patients during a visual backward-masking task.

OBJECTIVE: Schizophrenia patients experience deficits in many aspects of cognition and perception. Abnormalities in gamma activity may underlie some of these deficits, including rapid processing of visual stimuli. This study examined event-related gamma range activity during a visual backward-masking task in schizophrenia patients and normal comparison subjects. METHOD: Event-related gamma activity was recorded in 15 normal comparison subjects and 32 schizophrenia patients. Participants had event-related gamma activity recorded while viewing 60 unmasked visual targets and 240 trials of visual backward masking. Effects of group, accuracy (correct versus incorrect), stimulus-onset asynchrony, and regional activity (left versus right hemisphere, anterior versus posterior regions) were assessed. RESULTS: Schizophrenia patients had significantly reduced gamma activity in relation to comparison subjects during the backward-masking task. Normal comparison subjects showed significantly greater gamma activity in the right hemisphere, whereas schizophrenia patients did not show this pattern of lateralization. For the unmasked target, there was no group effect and no significant interactions in gamma-band responses. CONCLUSIONS: These results extend previous findings of abnormal gamma range activity in schizophrenia patients. Patients showed overall less gamma activity and failed to show lateralization of activity to the right hemisphere during masking, but they showed comparable levels of gamma activity to unmasked stimuli. Schizophrenia patients' poorer performance during a masking task may be partly influenced by this abnormal level and the distribution of gamma activity.

Adult↗
PubMed2005

Extensions of errorless learning for social problem-solving deficits in schizophrenia.

OBJECTIVE: There is a clear need to develop psychosocial rehabilitation methods that compensate for neurocognitive deficits common to persons with severe and persistent mental illness. Errorless learning, a compensatory training intervention, has been successful in teaching entry-level job tasks. However, errorless learning's applicability to broader, more complex functions is unknown. The present study tested the extension of errorless learning for deficits in social problem-solving skills in patients with schizophrenia. METHOD: Sixty clinically stable outpatients with schizophrenia or schizoaffective disorder were stratified by gender and level of memory impairment before being randomly assigned to one of two training programs: errorless learning or symptom management. Groups were matched for training time, format and structure of training, and types of teaching aids used. Social problem-solving ability, measured by the Assessment of Interpersonal Problem-Solving Skills, was assessed at baseline, within 2 days of training completion, and after 3 months. Dependent measures were the scores for the receiving, processing, and sending skills areas from the Assessment of Interpersonal Problem-Solving Skills. RESULTS: A repeated-measures analysis of covariance was conducted for each dependent measure with baseline Assessment of Interpersonal Problem-Solving Skills score entered as a covariate. For all three skills, there was a significant training group effect favoring errorless learning. Durability of errorless learning training effects extended to the 3-month follow-up assessment for processing and sending skills but not receiving skills. CONCLUSIONS: Results support the extension of errorless learning to complex functions such as social problem-solving skills in the rehabilitation of persons with schizophrenia.

Adult↗
PubMed2005

The effects of clozapine and risperidone on spatial working memory in schizophrenia.

OBJECTIVE: The purpose of this investigation was to evaluate the effects of clozapine and risperidone on spatial working memory in patients with schizophrenia. METHOD: Spatial working memory performance was evaluated at baseline and after 17 and 29 weeks in 97 patients with schizophrenia participating in a multisite trial. RESULTS: Compared with baseline performance while receiving conventional antipsychotic medication, risperidone improved, and clozapine worsened, spatial working memory performance. CONCLUSIONS: The differential effects of these medications on spatial working memory may be due to the anticholinergic effects of clozapine and prefrontal dopamine-enhancing effects of risperidone.

Adult↗
PubMed2005

Modulation of attention during visual masking in schizophrenia.

OBJECTIVE: Schizophrenia patients consistently demonstrate performance deficits on visual masking procedures. The present study examined whether attentional manipulation would improve subjects' performance on visual masking. METHOD: A metacontrast task was administered to 105 schizophrenia patients and 52 healthy comparison subjects. Attention was manipulated by associating selected trials of the task with monetary reward. RESULTS: Schizophrenia patients exhibited poorer performance than the comparison subjects across conditions. Patients demonstrated modest, but statistically significant, improvement in performance with the attentional manipulation. This improvement was not significant for the comparison subjects. CONCLUSIONS: These findings suggest that early visual processes in schizophrenia are responsive to attentional manipulation but that the degree of improvement is relatively small, suggesting that these processes are not easily altered.

Attention↗
PubMed2005

Independent effects of tobacco abstinence and bupropion on cognitive function in schizophrenia.

OBJECTIVE: The objective of this study was to examine the effects of tobacco abstinence and bupropion treatment on cognitive functioning in adult smokers with schizophrenia in the setting of a randomized, double-blind, placebo-controlled clinical trial of bupropion for smoking cessation. METHOD: Fifty-three adults with schizophrenia (DSM-IV) took part in a trial of bupropion for smoking cessation. Subjects were enrolled in the study from August 1999 to March 2003. Forty-five subjects remained in the trial at week 4; 41 subjects, 19 taking bupropion and 22 taking placebo, completed the baseline and week 4 cognitive assessments and were included in the analysis of adjusted effects of abstinence and bupropion treatment on cognitive function. RESULTS: Controlling for bupropion treatment and baseline performance, 7 days of tobacco abstinence was associated with slowed motor speed (finger tapping) but was not associated with worsening of performance on tests of attention (AX Continuous Performance Test [AX-CPT]), verbal learning and memory (California Verbal Learning Test [CVLT]), working memory (digit span), or executive function/inhibition (Stroop) and was not associated with worsening of any clinical measures. Controlling for abstinence status, bupropion was associated with reduction (improvement) in reaction time variability on the AX-CPT and with reduction in perseverative errors on the CVLT. CONCLUSION: We conclude that 1 week of tobacco abstinence is associated with slowed motor speed but is not associated with detectable worsening in performance on a range of neuropsychological tests or clinical symptoms in the subset of patients who were able to quit smoking. We also conclude that bupropion treatment may be associated with improvement in variability of attention.

Adult↗
PubMed2004

NIMH-MATRICS survey on assessment of neurocognition in schizophrenia.

The NIMH-Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative requires, among other things, the establishment of a reliable, valid, and consensus-derived method of assessing cognition. The derived battery will provide a standardized way to assess the effects of cognition-enhancing agents across clinical trials. To this end, the first of six consensus-oriented conferences was held April 2003. The goals were twofold: (a) To select which cognitive constructs to measure in a consensus battery, and (b) to select which criteria to use in evaluating tests for inclusion in the battery. Based on consultation with experts on the RAND Panel Method, 74 experts were invited to participate in a pre-meeting survey to provide information relevant to decisions on the cognitive battery. The survey included sections on reliability, validity, test administration, norms and interpretation of tests, cognitive domains and their integration, battery duration, and overall importance of test qualities. For selection of cognitive targets, the results showed that experts ranked executive functions, attention/vigilance, memory processes, and problem-solving ability highest. For test qualities, the experts ranked test-retest reliability, good coverage of key individual cognitive constructs, and comparable alternate forms highest. This article presents the results of the pre-conference survey that was the first step in the RAND process towards development of the NIMH-MATRICS consensus battery to assess cognition in schizophrenia.

Attention↗
PubMed2004

Identification of separable cognitive factors in schizophrenia.

One of the primary goals in the NIMH initiative to encourage development of new interventions for cognitive deficits in schizophrenia, Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS), has been to develop a reliable and valid consensus cognitive battery for use in clinical trials. Absence of such a battery has hampered standardized evaluation of new treatments and, in the case of pharmacological agents, has been an obstacle to FDA approval of medications targeting cognitive deficits in schizophrenia. A fundamental step in developing such a battery was to identify the major separable cognitive impairments in schizophrenia. As part of this effort, we evaluated the empirical evidence for cognitive performance dimensions in schizophrenia, emphasizing factor analytic studies. We concluded that seven separable cognitive factors were replicable across studies and represent fundamental dimensions of cognitive deficit in schizophrenia: Speed of Processing, Attention/Vigilance, Working Memory, Verbal Learning and Memory, Visual Learning and Memory, Reasoning and Problem Solving, and Verbal Comprehension. An eighth domain, Social Cognition, was added due to recent increased interest in this area and other evidence of its relevance for clinical trials aiming to evaluate the impact of potential cognitive enhancers on cognitive performance and functional outcome. Verbal Comprehension was not considered appropriate for a cognitive battery intended to be sensitive to cognitive change, due to its resistance to change. The remaining seven domains were recommended for inclusion in the MATRICS-NIMH consensus cognitive battery and will serve as the basic structure for that battery. These separable cognitive dimensions also have broader relevance to future research aimed at understanding the nature and structure of core cognitive deficits in schizophrenia.

Arousal↗
PubMed2004

Longitudinal studies of cognition and functional outcome in schizophrenia: implications for MATRICS.

It is generally accepted that cognitive deficits in schizophrenia are related to functional outcome. However, support for longitudinal relationships between cognition and functional outcome has not been as well documented. The current paper presents a review of 18 recently published longitudinal studies (minimum 6-month follow up) of the relationships between cognition and community outcome in schizophrenia. Results from these studies reveal considerable support for longitudinal associations between cognition and community outcome in schizophrenia. These studies demonstrate that cognitive assessment predict later functional outcome and provide a rationale for psychopharmacological interventions for cognitive deficits in schizophrenia. Although the relationships between cognition and community outcome are well-supported, it is clear that community functioning is also affected by a host of factors apart from cognition that are usually not considered in clinical trial studies (e.g., psychosocial rehabilitation and educational/vocational opportunities). In the second part of the paper, we consider intervening steps between cognitive performance measures and community outcome. These steps are apt to have important implications for clinical trials of cognition-enhancing agents in schizophrenia.

Antipsychotic Agents↗