44 research outputs found

    Shape and volume changes of the superior lateral ventricle after electroconvulsive therapy measured with ultra-high field MRI

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    The subventricular zone (SVZ) of the lateral ventricles harbors neuronal stem cells in adult mammals. Rodent studies report neurogenic effects in the SVZ of electroconvulsive stimulation. We hypothesize that if this finding translates to depressed patients undergoing electroconvulsive therapy (ECT), this would be reflected in shape changes at the SVZ. Using T1-weighted MR images acquired at ultra-high field strength (7T), the shape and volume of the ventricles were compared from pre to post ECT after 10 ECT sessions (in patients twice weekly) or 5 weeks apart (controls) using linear mixed models with age and gender as covariates. Ventricle shape significantly changed and volume significantly decreased over time in patients for the left ventricle, but not in controls. The decrease in volume of the ventricles was associated to a decrease in depression scores, and an increase in the left dentate gyrus, However, the shape changes of the ventricles were not restricted to the neurogenic niche in the lateral walls of the ventricles, providing no clear evidence for neurogenesis as sole explanation of volume changes in the ventricles after ECT

    Rule induction performance in amnestic mild cognitive impairment and Alzheimer’s dementia: examining the role of simple and biconditional rule learning processes

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    Introduction: Rule induction tests such as the Wisconsin Card Sorting Test require executive control processes, but also the learning and memorization of simple stimulus–response rules. In this study, we examined the contribution of diminished learning and memorization of simple rules to complex rule induction test performance in patients with amnestic mild cognitive impairment (aMCI) or Alzheimer’s dementia (AD). Method: Twenty-six aMCI patients, 39 AD patients, and 32 control participants were included. A task was used in which the memory load and the complexity of the rules were independently manipulated. This task consisted of three conditions: a simple two-rule learning condition (Condition 1), a simple four-rule learning condition (inducing an increase in memory load, Condition 2), and a complex biconditional four-rule learning condition—inducing an increase in complexity and, hence, executive control load (Condition 3). Results: Performance of AD patients declined disproportionately when the number of simple rules that had to be memorized increased (from Condition 1 to 2). An additional increment in complexity (from Condition 2 to 3) did not, however, disproportionately affect performance of the patients. Performance of the aMCI patients did not differ from that of the control participants. In the patient group, correlation analysis showed that memory performance correlated with Condition 1 performance, whereas executive task performance correlated with Condition 2 performance. Conclusions: These results indicate that the reduced learning and memorization of underlying task rules explains a significant part of the diminished complex rule induction performance commonly reported in AD, although results from the correlation analysis suggest involvement of executive control functions as well. Taken together, these findings suggest that care is needed when interpreting rule induction task performance in terms of executive function deficits in these patients

    Auditory hallucinations, top-down processing and language perception: a general population study

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    Background: Studies investigating the underlying mechanisms of hallucinations in patients with schizophrenia suggest that an imbalance in top-down expectations v. bottom-up processing underlies these errors in perception. This study evaluates this hypothesis by testing if individuals drawn from the general population who have had auditory hallucinations (AH) have more misperceptions in auditory language perception than those who have never hallucinated. Methods: We used an online survey to determine the presence of hallucinations. Participants filled out the Questionnaire for Psychotic Experiences and participated in an auditory verbal recognition task to assess both correct perceptions (hits) and misperceptions (false alarms). A hearing test was performed to screen for hearing problems. Results: A total of 5115 individuals from the general Dutch population participated in this study. Participants who reported AH in the week preceding the test had a higher false alarm rate in their auditory perception compared with those without such (recent) experiences. The more recent the AH were experienced, the more mistakes participants made. While the presence of verbal AH (AVH) was predictive for false alarm rate in auditory language perception, the presence of non-verbal or visual hallucinations were not. Conclusions: The presence of AVH predicted false alarm rate in auditory language perception, whereas the presence of non-verbal auditory or visual hallucinations was not, suggesting that enhanced top-down processing does not transfer across modalities. More false alarms were observed in participants who reported more recent AVHs. This is in line with models of enhanced influence of top-down expectations in persons who hallucinate.publishedVersio

    Raloxifene augmentation in men and women with a schizophrenia spectrum disorder:A study protocol

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    Although acute psychotic symptoms are often reduced by antipsychotic treatment, many patients with schizophrenia are impaired in daily functioning due to the persistence of negative and cognitive symptoms. Raloxifene, a Selective Estrogen Receptor Modulator (SERM) has been shown to be an effective adjunctive treatment in schizophrenia. Yet, there is a paucity in evidence for raloxifene efficacy in men and premenopausal women. We report the design of a study that aims to replicate earlier findings concerning the efficacy of raloxifene augmentation in reducing persisting symptoms and cognitive impairment in postmenopausal women, and to extend these findings to a male and peri/premenopausal population of patients with schizophrenia. The study is a multisite, placebo-controlled, double-blind, randomised clinical trial in approximately 110 adult men and women with schizophrenia. Participants are randomised 1:1 to adjunctive raloxifene 120 mg or placebo daily during 12 weeks. The treatment phase includes measurements at three time points (week 0, 6 and 12), followed by a follow-up period of two years. The primary outcome measure is change in symptom severity, as measured with the Positive and Negative Syndrome Scale (PANSS), and cognition, as measured with the Brief Assessment of Cognition in Schizophrenia (BACS). Secondary outcome measures include social functioning and quality of life. Genetic, hormonal and inflammatory biomarkers are measured to assess potential associations with treatment effects. If it becomes apparent that raloxifene reduces psychotic symptoms and/or improves cognition, social functioning and/or quality of life as compared to placebo, implementation of raloxifene in clinical psychiatric practice can be considered

    Increased risk of psychosis in patients with hearing impairment : Review and meta-analyses

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    Several studies suggest hearing impairment as a risk factor for psychosis. Hearing impairment is highly prevalent and potentially reversible, as it can be easily diagnosed and sometimes improved. Insight in the association between hearing impairment and psychosis can therefore contribute to prevention of psychosis. This paper provides meta-analyses of all epidemiologic evidence on the association between hearing impairment and psychosis and summarizes mechanisms that potentially underlie this relationship.Meta-analyses showed an increased risk of hearing impairment on all psychosis outcomes, such as hallucinations (OR 1.40(95%CI 1.18-1.65; n=. 227,005)), delusions (OR 1.55(95%CI 1.36-1.78; n=. 250,470)), psychotic symptoms (OR 2.23(95%CI 1.83-2.72; n=. 229,647) and delirium (OR 2.67(95%CI 2.05-3.48; n=. 12,432). Early exposure to hearing impairment elevated the risk of later development of schizophrenia (OR 3.15(95%CI 1.25-7.95; n=. 50,490)).Potential mechanisms underlying this association include loneliness, diminished theory of mind, disturbances of source monitoring and top-down processing and deafferentiation. Early assessment and treatment of hearing impairment in patients with (high risk of) psychosis may be essential in psychosis treatment and prevention

    Exercise Improves Clinical Symptoms, Quality of Life, Global Functioning, and Depression in Schizophrenia : A Systematic Review and Meta-analysis

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    BACKGROUND: Physical exercise may be valuable for patients with schizophrenia spectrum disorders as it may have beneficial effect on clinical symptoms, quality of life and cognition. METHODS: A systematic search was performed using PubMed (Medline), Embase, PsychInfo, and Cochrane Database of Systematic Reviews. Controlled and uncontrolled studies investigating the effect of any type of physical exercise interventions in schizophrenia spectrum disorders were included. Outcome measures were clinical symptoms, quality of life, global functioning, depression or cognition. Meta-analyses were performed using Comprehensive Meta-Analysis software. A random effects model was used to compute overall weighted effect sizes in Hedges' g. RESULTS: Twenty-nine studies were included, examining 1109 patients. Exercise was superior to control conditions in improving total symptom severity (k = 14, n = 719: Hedges' g = .39, P < .001), positive (k = 15, n = 715: Hedges' g = .32, P < .01), negative (k = 18, n = 854: Hedges' g = .49, P < .001), and general (k = 10, n = 475: Hedges' g = .27, P < .05) symptoms, quality of life (k = 11, n = 770: Hedges' g = .55, P < .001), global functioning (k = 5, n = 342: Hedges' g = .32, P < .01), and depressive symptoms (k = 7, n = 337: Hedges' g = .71, P < .001). Yoga, specifically, improved the cognitive subdomain long-term memory (k = 2, n = 184: Hedges' g = .32, P < .05), while exercise in general or in any other form had no effect on cognition. CONCLUSION: Physical exercise is a robust add-on treatment for improving clinical symptoms, quality of life, global functioning, and depressive symptoms in patients with schizophrenia. The effect on cognition is not demonstrated, but may be present for yoga

    Exercise improves clinical symptoms, quality of life, global functioning, and depression in schizophrenia: A systematic review and meta-analysis

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    Background: Physical exercise may be valuable for patients with schizophrenia spectrum disorders as it may have beneficial effect on clinical symptoms, quality of life and cognition. Methods: A systematic search was performed using PubMed (Medline), Embase, PsychInfo, and Cochrane Database of Systematic Reviews. Controlled and uncontrolled studies investigating the effect of any type of physical exercise interventions in schizophrenia spectrum disorders were included. Outcome measures were clinical symptoms, quality of life, global functioning, depression or cognition. Meta-analyses were performed using Comprehensive Meta-Analysis software. A random effects model was used to compute overall weighted effect sizes in Hedges' g. Results: Twenty-nine studies were included, examining 1109 patients. Exercise was superior to control conditions in improving total symptom severity (k = 14, n = 719: Hedges' g =. 39, P <. 001), positive (k = 15, n = 715: Hedges' g =. 32, P <. 01), negative (k = 18, n = 854: Hedges' g =. 49, P <. 001), and general (k = 10, n = 475: Hedges' g =. 27, P <. 05) symptoms, quality of life (k = 11, n = 770: Hedges' g =. 55, P <. 001), global functioning (k = 5, n = 342: Hedges' g =. 32, P <. 01), and depressive symptoms (k = 7, n = 337: Hedges' g =. 71, P <. 001). Yoga, specifically, improved the cognitive subdomain long-term memory (k = 2, n = 184: Hedges' g =. 32, P <. 05), while exercise in general or in any other form had no effect on cognition. Conclusion: Physical exercise is a robust add-on treatment for improving clinical symptoms, quality of life, global functioning, and depressive symptoms in patients with schizophrenia. The effect on cognition is not demonstrated, but may be present for yoga

    Sex hormones and oxytocin augmentation strategies in schizophrenia : A quantitative review

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    INTRODUCTION: Sex differences in incidence, onset and course of schizophrenia suggest sex hormones play a protective role in the pathophysiology. Such a role is also proposed for oxytocin, another important regulator of reproduction function. Evidence on the efficacy of sex hormones and oxytocin in the treatment of schizophrenia is summarized. METHODS: Double-blind, placebo-controlled, randomized studies were included, examining augmentation with estrogens, selective estrogen receptor modulators (SERMs), testosterone, dehydroepiandrosterone (DHEA), pregnenolone, and oxytocin. Outcome measures were total symptom severity, positive and negative symptom subscores, and cognition. In meta-analyses, combined weighted effect sizes (Hedges' g) per hormone were calculated. RESULTS: Twenty-four studies were included, examining 1149 patients. Significant effects were found for estrogen action (k=10), regarding total symptoms (Hedges' g=0.63, p=0.001), positive (Hedges' g=0.42, p<0.001), and negative symptoms (Hedges' g=0.35, p=0.001). Subgroup analyses yielded significant results for estrogens in premenopausal women (k=6) for total, positive, and negative symptoms, and for the SERM raloxifene in postmenopausal women (k=3) for total and negative, but not positive symptoms. Testosterone augmentation in males (k=1) was beneficial only for negative symptoms (Hedges' g=0.82, p=0.027). No overall effects were found for DHEA (k=4), pregnenolone (k=4), and oxytocin (k=6). Results for cognition (k=12) were too diverse for meta-analyses, and inspection of these data showed no consistent benefit. CONCLUSIONS: Estrogens and SERMs could be effective augmentation strategies in the treatment of women with schizophrenia, although potential side effects, partially associated with longer duration use, should be taken into account. Future trials are needed to study long-term effects and effects on cognition
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