Globus pallidus internus oscillatory activity is related to movement speed

Local field potentials (LFPs) recorded from deep brain stimulation electrodes implanted in the globus pallidus internus (GPi) of patients with hyperkinetic movement disorders (dystonia and Tourette's syndrome) have shown desynchronized activity at 8–20 Hz and synchronized activity at 30–90 Hz during voluntary movements. However, the impact of the speed of the motor task on these frequency shifts is still unclear. In the current study, we recorded LFPs bilaterally from the GPi in seven patients with hyperkinetic movement disorders during normal/slow and fast horizontal line drawing movements as well as during rest. In comparison with rest, the low beta band showed a significant decrease in power during the motor tasks. Low beta power was more suppressed with increasing speed of the movement on the contralateral side. In contrast, a significant increase in power was induced by movements in the high beta and gamma bands on the contralateral side. When comparing slow and fast movements, the power of the low gamma frequency band was significantly elevated on the contralateral side with fast movements. In conclusion, an increase in movement speed changes the power of GPi oscillations by means of a reduction of the activity in the low beta band and an elevation of activity in the gamma band. The current study yields new insights into the physiological mechanism of GPi during the execution of the motor task at low and high speed.     

Impaired P600 in neuroleptic naive patients with first-episode schizophrenia

Deficits of working memory (WM) are recognized as an important pathological feature in schizophrenia. Since the P600 component of event related potentials has been hypothesized that represents aspects of second-pass parsing processes of information processing, and is related to WM, the present study focuses on P600 elicited during a WM test in drug-naive first-episode schizophrenics (FES) compared to healthy controls. We examined 16 drug-naive first-episode schizophrenic patients and 23 healthy controls matched for age and sex. Compared with controls schizophrenic patients showed reduced P600 amplitude on left temporoparietal region and increased P600 amplitude on left occipital region. With regard to the latency, the patients exhibited significantly prolongation on right temporoparietal region. The obtained pattern of differences classified correctly 89.20% of patients. Memory performance of patients was also significantly impaired relative to controls. Our results suggest that second-pass parsing process of information processing, as indexed by P600, elicited during a WM test, is impaired in FES. Moreover, these findings lend support to the view that the auditory WM in schizophrenia involves or affects a circuitry including temporoparietal and occipital brain areas.     

Anticipated discrimination is related to symptom severity,functionality and quality of life in schizophrenia

The aim of this study is to evaluate a possible relationship between the level of anticipated discrimination with severity of symptoms and functionality. We included 103 patients with schizophrenia. Severity of symptoms was measured by PANSS and Calgary Depression Scale for Schizophrenia. Quality of life (QL) and functionality were measured by using QLS, PSP and Functional Remission of General Schizophrenia Scale (FROGS). Anticipated/experienced discrimination was evaluated with four selected items from Discrimination and Stigma Scale.     

Single-unit activity of the anterior Globus pallidus internus in Tourette patients and posterior Globus pallidus internus in dystonic patients

Objectives

Our goal was to provide a detailed analysis of neurons’ electrophysiological activity recorded in sub-territories of Globus pallidus internus (GPi) used as Deep Brain Stimulation (DBS) targets for these clinical conditions to potentially assist electrode targeting.

Gender differences in the relationship of homelessness to symptom severity, substance abuse, and neuroleptic noncompliance in schizophrenia

This study examined gender differences in the relationship of homelessness in schizophrenia to symptom severity, risk behaviors, and prognostic features. Four hundred subjects with schizophrenia were studied: 100 homeless men, 100 homeless women, 100 never homeless men, and 100 never homeless women. Assessments included derivation of five symptom factors by using the Positive and Negative Syndrome Scale (PANSS). Homelessness for the entire sample was associated with greater severity of positive, activation, and autistic preoccupation symptoms, younger age at first hospitalization, and substance abuse (SA). For men only, homelessness was associated with neuroleptic noncompliance (NN). When NN and SA were statistically controlled, symptom severity was not different between the homeless and never homeless. Women, independent of residential status, had more severe negative, activation, and autistic preoccupation symptoms that were not associated with prognostic features or risk behaviors. For both men and women, SA was associated with homelessness, but independent of residence, SA was less severe in women. Additionally, SA was less severe in homeless women than never homeless men. Thus, symptom severity in homeless individuals with schizophrenia appears as an interaction of symptom profiles and risk behaviors that are gender specific. Although cross-sectional analyses cannot distinguish cause from effect, these findings suggest gender-specific routes to homelessness among indigent urban adults with schizophrenia.     

Itemized clinician ratings versus global ratings of symptom severity in patients with schizophrenia

This study compares ratings obtained with an itemized clinician-rated symptom severity measure--the 24-item Brief Psychiatric Rating Scale (BPRS24)--with a Physician Global Rating Scale (PhGRS) and a Patient Global Rating Scale (PtGRS) in assessing treatment outcomes in patients with schizophrenia (SCZ). A total of 91 patients (31 inpatients and 60 outpatients) with SCZ were enrolled in a feasibility study of the use of medication algorithms in the treatment of SCZ. Clinicians completed the BPRS24 and the PhGRS; patients completed the PtGRS at each visit. The analyses reported here were conducted using the original BPRS18 and four items from the BPRS18 that rate the positive symptoms of psychosis (the Positive Symptom Rating Scale or PSRS), comparing anchored with global rating scales and with one another. The PtGRS had the lowest effect size (0.8) and was negatively correlated with the other ratings in inpatients. The PhGRS was significantly correlated (0.46) with the BPRS18, but the same person completed both ratings. The effect size of the PhGRS (0.6) was generally lower than with the BPRS18 (1.4) in differentiating responders from non-responders. On average, the PSRS had a slightly lower effect size than the longer itemized BPRS18, but the results support its use as a quantitative rating in circumstances where it is not feasible to routinely use a lengthier scale.     

Older patients with schizophrenia: nature of dwelling status and symptom severity

OBJECTIVE: This cross-sectional study enrolled elderly patients with diagnoses of schizophrenia or schizoaffective disorder. METHOD: The 85 subjects were dichotomized into two groups on the basis of dwelling status: those living independently (N=35) and those living in residential settings (N=50). The groups were compared with regard to scores on the Mini-Mental State Examination (MMSE), the Brief Psychiatric Rating Scale, the Scale for the Assessment of Negative Symptoms (SANS), the Geriatric Depression Scale and by age. RESULTS: Patients living independently had significantly higher MMSE scores, lower SANS scores, more years of education, and were younger than the patients living in residential settings. CONCLUSIONS: These data suggest that although cognition, negative symptoms, and age are important discriminators with regard to dwelling status, cognition and negative symptoms appear to have the strongest impact.     

Deficient attentional modulation of startle eyeblink is associated with symptom severity in the schizophrenia spectrum

Patients with schizophrenia-spectrum disorders show deficient prepulse inhibition (PPI) of the startle eyeblink reflex which is thought to reflect an early stage of information processing called automatic sensorimotor gating. They also exhibit deficient attentional modulation of PPI and prepulse facilitation (PPF) of startle which is thought to reflect deficient early and later controlled attentional processing. This is the first study to assess attentional modulation of PPI and PPF in a 3-group schizophrenia-spectrum sample of age- and sex-matched unmedicated schizotypal personality disorder (SPD) and schizophrenia patients, and healthy controls. Participants performed a tone-length judgment task involving attended, ignored, and novel tone prepulses while the acoustic startle eyeblink reflex was measured. Healthy controls showed greater PPI and PPF during the attended prepulses compared with the ignored prepulses. In contrast, both the SPD and schizophrenia patient groups failed to show this pattern, indicating deficient early and later controlled attentional processing. These findings suggest abnormal attentional modulation of PPI and PPF may be a trait-like feature found in patients with schizophrenia-spectrum disorders. Among the schizophrenia-spectrum sample, more deficient PPI during the attended prepulses was associated with greater symptom severity as measured by the total 18-item Brief Psychiatric Rating Scale score.     

Cognitive functioning, cortisol release, and symptom severity in patients with schizophrenia.

BACKGROUND: There is substantial evidence of dysregulation of cortisol secretion, hippocampal abnormalities, and memory deficits in schizophrenia and other psychotic disorders. Research also suggests that cortisol secretion augments dopaminergic activity, which may result in increased symptom expression in this clinical population. METHODS: We examined the relations among cortisol release, cognitive performance, and psychotic symptomatology. Subjects were 18 adults with schizophrenia or schizoaffective disorder, seven with a nonpsychotic psychiatric disorder, and 15 normal control subjects. Tests of memory and executive function were administered. Cortisol was assayed from multiple saliva samples. RESULTS: Findings indicated the following: 1) patients with psychotic disorders scored below the comparison groups on the cognitive measures; 2) for the entire sample, cortisol levels were inversely correlated with performance on memory and frontal tasks; and 3) among patients, cortisol levels were positively correlated with ratings of positive, disorganized, and overall symptom severity, but not with negative symptoms. CONCLUSIONS: The present results suggest that abnormalities in the hypothalamic-pituitary-adrenal axis and hippocampal systems play a role in observed cognitive deficits across populations. Among psychotic patients, elevated cortisol secretion is linked with greater symptom severity.     

Discontinuation of neuroleptic treatment in patients with schizophrenia

Neuroleptic maintenance treatment in schizophrenia is a conflicting issue. There is no reliable criteria to identify patients for which neuroleptic withdrawal can be experienced. However, treatment discontinuation, whose risks can be limited, must be attempted for reasons such as the patient's wellbeing, longterm side-effects prevention and patient-doctor relationship management. Anyway, it can lead to more specific indications for drug maintenance.     

Globus pallidus calcification in Down syndrome with progressive neurologic deficits.

We report a 10-year-old Down syndrome patient who developed dystonia, choreoathetosis, dysarthria, and dysphagia beginning with hemiparesis. Cranial computed tomography disclosed bilateral calcification in the globus pallidus which resembled a sign of premature aging. Conversely, the clinical course and magnetic resonance imaging findings resembled those of Hallervorden-Spatz syndrome.     

Relationship of psychotic symptom clusters in schizophrenia to neuroleptic treatment and growth hormone response to apomorphine

The authors propose an alternative model for relating clinically rated psychotic symptoms to biological measures in schizophrenic patients. They suggest that clinical presentation in schizophrenic patients comprises at least four distinct psychotic symptom clusters and that at most one or two of the symptom clusters are closely associated with central dopamine (DA) activity as measured by growth hormone (GH) response to apomorphine. Factor and cluster analytic techniques both identified the same four psychotic symptom clusters, three of which were similar to the major subtypes of schizophrenia: paranoid delusions (paranoid type), thought disorder (disorganized type), and catatonia (catatonic type). The fourth psychotic symptom cluster was auditory hallucinations, a prominent clinical feature of schizophrenia. The authors compared clinical symptom cluster scores to apomorphine-induced GH response by creating a new data set containing the output of the factor analysis of each patient's symptoms and GH response, and performing regression modeling of the patient's symptom cluster scores on GH response. Patients with elevated thought disorder cluster scores also had elevated GH responses to apomorphine, suggesting an association between thought disorder and central DA receptor supersensitivity. A fixed-dose neuroleptic trial showed that thought disorder and auditory hallucinations respond rapidly to treatment with a DA receptor blocker (haloperidol), while no significant effect on other symptom cluster scores occurred during the initial 2 weeks of treatment. These data suggest that two of the identified symptom clusters, thought disorder and auditory hallucinations, may be preferentially associated with central DA hyperactivity.     

Correlates of rapid neuroleptic response in male patients with schizophrenia

Correlates of neuroleptic response latency were assessed in 16 male schizophrenic inpatients during 4 weeks of fixed dose (20 mg/day) haloperidol treatment. Rapid responders showed a mean 40% reduction in Brief Psychiatric Rating Scale (BPRS) positive symptom scores by day 10 of treatment. Rapid responders had significantly lower plasma homovanillic acid (pHVA) concentrations compared to non-rapid responders during week 4 of haloperidol treatment. However, rapid versus non-rapid responders did not differ with respect to demographics, baseline positive or negative BPRS symptom scores, performance on tests of neuropsychological function, or mean plasma haloperidol concentrations.     

Disordered eating attitudes in Egyptian antipsychotic naive patients with schizophrenia

ObjectivesThe study aimed to test in a sample of Egyptian antipsychotic naive patients the hypotheses that the disordered eating attitudes co-occur with schizophrenia in a higher frequency than would be expected by chance in the general population and that the disordered eating comorbidity would be associated with more severe schizophrenia psychopathology. Previous studies have been mostly concerned with the impact of the antipsychotics. Studies relating abnormal eating behavior to the schizophrenia psychopathology rather than to its treatment are lacking.MethodIn this case-control cross-sectional study, 50 consecutive antipsychotic naive patients, newly attending the psychiatric outpatient clinic, University Hospital, Zagazig, Egypt, with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnosis of schizophrenia, were assessed by the Positive and Negative Syndrome Scale and compared with 50 nonpsychiatric controls using the Eating Attitudes Test (EAT40).ResultsPatients with schizophrenia had an EAT40 mean score (23.4 ± 7.8) higher than that of controls (19.7 ± 7.2) (P = .015). Prevalence of disordered eating (defined by a score of ≥30 on the EAT40) in these patients was higher than in the control group (30% vs 12%, P = .027). Comparison between schizophrenia patients with and without disordered eating showed no significant differences in demographic and a number of clinical variables, but they differed in their scores on lifestyle characteristics and anthropometric measures. The group of patients with disordered eating had also higher scores on total and all scale factors but not on the negative symptom scale.ConclusionsData of this study show, perhaps for the first time, that “disordered” eating attitudes, as measured by the EAT40, are higher in a group of Egyptian patients with schizophrenia than in controls. However, the lack of difference between patients with and without disordered eating in terms of demographic and a number of clinical characteristics fail to explain the hypothesis that schizophrenia with disordered eating is a distinct subtype of schizophrenia. Data indicate, on the other hand, that the presence of disordered eating behavior in patients with schizophrenia is associated with the expression of more active psychotic symptoms.     

Association of symptom severity,insight and increased pharmacologic side effects in acutely hospitalized patients with schizophrenia

Background

Many studies have shown that more severe symptoms and poorer insight are associated with poor treatment compliance in schizophrenia while severe symptoms may result in higher medication dosages. Since pharmacologic side effects may accompany greater medication compliance and higher medication dosage, the relationship between symptoms, insight and side effects deserves study.

Methods

In this study, 174 inpatients diagnosed with schizophrenia were assessed during the week before hospital discharge from a large psychiatric hospital in Guangzhou, China. Symptoms were measured by the Positive and Negative Syndrome Scale for Schizophrenia (PANSS). Insight was assessed by the Insight and Treatment Attitudes Questionnaire (ITAQ). Pharmacologic side effects were assessed by the Treatment Emergent Symptoms Scale (TESS). Bivariate and multivariate regression models were used to examine the relationship of symptoms, insight and the interaction between the two, to the severity of side effects.

Results

As expected, the PANSS total score was significantly associated with poorer ITAQ scores and with more severe side effects, and on multivariate analysis both higher PANSS and lower ITAQ scores were associated with more severe side effects. Stepwise multiple linear regression analysis showed that the model with the PANSS total score alone explained 3.4% of the variance in side-effect scores, while adding the ITAQ increased the explained variance to 11.8%. Analysis of the interaction of symptoms and insight showed that patients with both more severe symptoms and high insight had the most severe side effects (B = .006, p = .008, R² = 15.4%).

Conclusion

More severe symptoms and greater insight among schizophrenic inpatients were both significantly if modestly associated with more severe pharmacologic side effects, the former presumably because of the need for higher doses of medication and the latter because of greater medication compliance. In addition, patients with both more severe symptoms and greater insight were even more prone to pharmacologic side effects than others presumably reflecting higher doses and higher compliance. Clinicians treating highly symptomatic but insightful patients, i.e. those most likely to need and to adhere to prescribed medications, may need to be especially vigilant about side effects.     

Memory and attention deficits in drug naive patients with schizophrenia

The present study was designed to evaluate the integrity of cognitive fronto-temporal processes in drug naive patients with schizophrenia. The evaluation of drug naive patients discards the potential influence of medication, and may allow the specification of cognitive impairments that are truly illness-related. Subcomponents of long-term memory as well as several measures of attention were examined. A group of 16 patients who had never taken antipsychotics and a group of 20 normal controls underwent tests of alertness, information maintaining, and sustained and selective attention, as well as tests of explicit and implicit recall. The psychopathological manifestations of patients were also assessed with the BPRS, PANSS, ESRS clinical scales. Attention test performances revealed that drug naive patients presented a decrease in their ability to respond promptly to a stimulus, sustain their attention on a task, display normal selective attention strategies, and maintain information for on-line processing. The results also suggest that the drug naive patients are impaired when both strategic and associative processes must be triggered to explicitly recover information in long-term memory. In contrast, the results revealed that implicit access to perceptual mental representations is spared in schizophrenic patients. Finally, features of the patients' clinical symptomatology and some cognitive deficits were also shown to be correlated. Overall, results showed that, in relation to normals, drug naive patients were mildly impaired, with little intersubject variability, and that not all cognitive processes were equally disturbed in relation to the normal subjects' performances. Results support the idea that an important part of the impairments seen in schizophrenia is present before the introduction of neuroleptic medication and chronic illness.     

Arousability in schizophrenia: relationship to emotional and physiological reactivity and symptom severity

Objective: Socioenvironmental stressors have been linked with increased symptom severity and relapse in those with schizophrenia. However, little is known about how individual differences in stress reactivity may contribute to these outcomes. Method: This study examined the association between the temperament characteristic of arousability and changes in negative affect and cardiovascular activity during a challenge task in 58 in‐patients with diagnosis of schizophrenia and 21 controls. Results: In the patient group, levels of arousability were significantly associated with increases in negative affect in response to the task and greater severity of affective symptoms. Levels of arousability were associated with decreased heart rate during the challenge task in our patient group. Conclusion: These findings suggest that greater attention be given to individual differences, such as temperament and personality characteristics, and their role in the experience of stressors, including emotional and physiological response, as well as symptom development.