152 research outputs found
Clonidine augmentation in patients with schizophrenia:A double-blind, randomized placebo-controlled trial
Introduction: Noradrenergic imbalance in the brain of schizophrenia patients may underlie both symptomatology and deficits in basic information processing. The current study investigated whether augmentation with the noradrenergic α2-agonist clonidine might alleviate these symptoms. Methods: In a double-blind placebo-controlled randomized clinical trial, 32 chronic schizophrenia patients were randomly assigned to six-weeks augmentation with either 50 μg clonidine or placebo to their current medication. Effects on symptom severity and both sensory- and sensorimotor gating were assessed at baseline, 3- and 6-weeks. Results were compared with 21 age- and sex-matched healthy controls (HC) who received no treatment. Results: Only patients treated with clonidine showed significantly reduced PANSS negative, general and total scores at follow-up compared to baseline. On average, also patients treated with placebo showed minor (non-significant) reductions in these scores, likely indicating a placebo effect. Sensorimotor gating of patients was significantly lower at baseline compared to controls. It increased in patients treated with clonidine over the treatment period, whereas it decreased in both the HC and patients treated with placebo. However, neither treatment nor group effects were found in sensory gating. Clonidine treatment was very well tolerated. Conclusion: Only patients treated with clonidine showed a significant decrease on two out of the three PANSS subscales, while additionally retained their levels of sensorimotor gating. Given that there are only a few reports on effective treatment for negative symptoms in particular, our current results support augmentation of antipsychotics with clonidine as a promising, low-cost and safe treatment strategy for schizophrenia
Гестационный транзиторный тиреотоксикоз
Приведены современные данные литературы о гестационном транзиторном тиреотоксикозе. Освещены особенности гормональной регуляции щитовидной железы.Modern literature data about gestation thyrotoxicosis are presented. The peculiarities of hormonal regulation of the thyroid gland are featured
Two sides of the same coin? How are neural mechanisms of cognitive control, attentional difficulties and creativity related?
Creativity has been associated with increased distractibility, but at the same time - and seemingly paradoxically- also with increased focused attention. Therefore, this study focused on the attentional processes involved in creativity and attentional difficulties. Healthy primary school children (N = 62) between 9 and 13 years old performed a selective attention paradigm while electrophysiological measures were recorded that measured the neural mechanisms of cognitive control (P300), conflict monitoring (N200), and subconscious attentional shifts (Mismatch Negativity). Attentional difficulties were measured with a parental questionnaire and creativity was measured with a divergent mathematical creativity task and a creative drawing task. We found that more creativity was related to decreased neural mechanisms of cognitive control and conflict monitoring (i.e. less negative N200 and smaller P300 amplitudes), however without affecting task performance. In addition, attentional difficulties were related to less negative N200 amplitudes on the attended and non-attended standard trials of the selective attention paradigm, as well as reduced task performance. Tentatively, the current findings suggest that original responses are associated with decreased cognitive control, possibly by promoting remote associations. Furthermore, our data shows that attentional difficulties are associated with a lack of selective attention and impaired information processing. Hence, although less cognitive control is often referred to in a negative way, it might facilitate certain aspects of creative thinking without affecting task performance
Prolonged-release melatonin versus placebo for benzodiazepine discontinuation in patients with schizophrenia: a randomized clinical trial - the SMART trial protocol
<p>Abstract</p> <p>Background</p> <p>Treatment of schizophrenia frequently includes prolonged benzodiazepine administration despite a lack of evidence of its use. It is often difficult to discontinue benzodiazepines because of the development of dependence. We aim to assess if melatonin can facilitate the withdrawal of prolonged benzodiazepine administration in patients with schizophrenia. Furthermore, we aim to investigate the association of benzodiazepine dose reduction with the following clinically important variables: sleep, psychophysiology, cognition, social function, and quality of life.</p> <p>Methods/Design</p> <p>Randomized, blinded, two-armed, parallel superiority trial. We plan to include 80 consenting outpatients diagnosed with schizophrenia or schizoaffective disorder, 18-55 years of age, treated with antipsychotic drug(s) and at least one benzodiazepine derivative for the last three months before inclusion. Exclusion criteria: currently under treatment for alcohol or drug abuse, aggressive or violent behavior, known mental retardation, pervasive developmental disorder, dementia, epilepsy, terminal illness, severe co morbidity, inability to understand Danish, allergy to melatonin, lactose, starch, gelatin, or talc, hepatic impairment, pregnancy or nursing, or lack of informed consent. After being randomized to prolonged-release melatonin (Circadin<sup>®</sup>) 2 mg daily or matching placebo, participants are required to slowly taper off their benzodiazepine dose. The primary outcome measure is benzodiazepine dose at 6 months follow-up. Secondary outcome measures include sleep, psychophysiological, and neurocognitive measures. Data are collected at baseline and at 6 months follow-up regarding medical treatment, cognition, psychophysiology, sleep, laboratory tests, adverse events, psychopathology, social function, and quality of life. Data on medical treatment, cognition, psychophysiology, adverse events, social function, and quality of life are also collected at 2 and 4 months follow-up.</p> <p>Discussion</p> <p>The results from this trial will examine whether melatonin has a role in withdrawing long-term benzodiazepine administration in schizophrenia patients. This group of patients is difficult to treat and therefore often subject to polypharmacy which may play a role in the reduced life expectancy of patients compared to the background population. The results will also provide new information on the association of chronic benzodiazepine treatment with sleep, psychophysiology, cognition, social function, and quality of life. Knowledge of these important clinical aspects is lacking in this group of patients.</p> <p>Trial Registration</p> <p>ClinicalTrials <a href="http://www.clinicaltrials.gov/ct2/show/NCT01431092">NCT01431092</a></p
Clonidine augmentation in patients with schizophrenia: A double-blind, randomized placebo-controlled trial
Introduction: Noradrenergic imbalance in the brain of schizophrenia patients may underlie both symptomatology and deficits in basic information processing. The current study investigated whether augmentation with the noradrenergic α2-agonist clonidine might alleviate these symptoms. Methods: In a double-blind placebo-controlled randomized clinical trial, 32 chronic schizophrenia patients were randomly assigned to six-weeks augmentation with either 50 μg clonidine or placebo to their current medication. Effects on symptom severity and both sensory- and sensorimotor gating were assessed at baseline, 3- and 6-weeks. Results were compared with 21 age- and sex-matched healthy controls (HC) who received no treatment. Results: Only patients treated with clonidine showed significantly reduced PANSS negative, general and total scores at follow-up compared to baseline. On average, also patients treated with placebo showed minor (non-significant) reductions in these scores, likely indicating a placebo effect. Sensorimotor gating of patients was significantly lower at baseline compared to controls. It increased in patients treated with clonidine over the treatment period, whereas it decreased in both the HC and patients treated with placebo. However, neither treatment nor group effects were found in sensory gating. Clonidine treatment was very well tolerated. Conclusion: Only patients treated with clonidine showed a significant decrease on two out of the three PANSS subscales, while additionally retained their levels of sensorimotor gating. Given that there are only a few reports on effective treatment for negative symptoms in particular, our current results support augmentation of antipsychotics with clonidine as a promising, low-cost and safe treatment strategy for schizophrenia
Serious Games as Potential Therapies: A Validation Study of a Neurofeedback Game
Serious (biofeedback) games offer promising ways to supplement or replace more expensive face-to-face interventions in health care. However, studies on the validity and effectiveness of EEG-based serious games remain scarce. In the current study, we investigated whether the conditions of the neurofeedback game "Daydream" indeed trained the brain activity as mentioned in the game manual. EEG activity was assessed in 14 healthy male volunteers while playing the 2 conditions of the game. The participants completed a training of 5 sessions. EEG frequency analyses were performed to verify the claims of the manual. We found significant differences in α- to β-ratio between the 2 conditions although only in the amplitude data, not in the power data. Within the conditions, mean α-amplitude only differed significantly from the β-amplitude in the concentration condition. Our analyses showed that neither α nor β brain activity differed significantly between game levels (higher level requiring increased brain activity) in either of the two conditions. In conclusion, we found only marginal evidence for the proposed claims stated in the manual of the game. Our research emphasizes that it is crucial to validate the claims that serious games make, especially before implementing them in the clinic or as therapeutic devices
Efficacy of different types of cognitive enhancers for patients with schizophrenia:a meta-analysis
Cognitive impairment is a core feature of schizophrenia, which is predictive for functional outcomes and is, therefore, a treatment target in itself. Yet, literature on efficacy of different pharmaco-therapeutic options is inconsistent. This quantitative review provides an overview of studies that investigated potential cognitive enhancers in schizophrenia. We included pharmacological agents, which target different neurotransmitter systems and evaluated their efficacy on overall cognitive functioning and seven separate cognitive domains. In total, 93 studies with 5630 patients were included. Cognitive enhancers, when combined across all different neurotransmitter systems, which act on a large number of different mechanisms, showed a significant (yet small) positive effect size of 0.10 (k = 51, p = 0.023; 95% CI = 0.01 to 0.18) on overall cognition. Cognitive enhancers were not superior to placebo for separate cognitive domains. When analyzing each neurotransmitter system separately, agents acting predominantly on the glutamatergic system showed a small significant effect on overall cognition (k = 29, Hedges' g = 0.19, p = 0.01), as well as on working memory (k = 20, Hedges' g = 0.13, p = 0.04). A sub-analysis of cholinesterase inhibitors (ChEI) showed a small effect on working memory (k = 6, Hedges' g = 0.26, p = 0.03). Other sub-analyses were positively nonsignificant, which may partly be due to the low number of studies we could include per neurotransmitter system. Overall, this meta-analysis showed few favorable effects of cognitive enhancers for patients with schizophrenia, partly due to lack of power. There is a lack of studies involving agents acting on other than glutamatergic and cholinergic systems, especially of those targeting the dopaminergic system.</p
Effects of bumetanide on neurodevelopmental impairments in patients with tuberous sclerosis complex: An open-label pilot study
Background: Tuberous sclerosis complex (TSC) is an autosomal dominant disease that affects multiple organs including the brain. TSC is strongly associated with broad neurodevelopmental disorders, including autism spectrum disorder symptomatology. Preclinical TSC studies have indicated altered neuronal chloride homeostasis affecting the polarity of γ-aminobutyric acid (GABA) ergic transmission as a potential treatment target. Bumetanide, a selective NKCC1 chloride importer antagonist, may attenuate depolarizing GABA action, and in that way reduce disease burden. In this open-label pilot study, we tested the effect of bumetanide on a variety of neurophysiological, cognitive, and behavioral measures in children with TSC. Methods: Participants were treated with bumetanide (2dd 0.5-1.0 mg) for 13 weeks in an open-label trial. The Aberrant Behavior Checklist-Irritability (ABC-I) subscale was chosen as the primary endpoint. Secondary endpoints included other behavioral questionnaires in addition to event-related potentials (ERP) and neuropsychological tests if tolerated. Additionally, the treatment effect on seizure frequency and quality of life was assessed. Endpoint data were collected at baseline, after 91 days of treatment and after a 28-day wash-out period. Results: Fifteen patients (8-21-years old) with TSC were included of which 13 patients completed the study. Treatment was well-tolerated with only expected adverse events due to the diuretic effects of bumetanide. Irritable behavior (ABC-I) showed significant improvement after treatment in 11 out of 13 patients (t(12) = 4.41, p =.001, d =.773). A favorable effect was also found for social behavior (Social Responsiveness Scale) (t(11) = 4.01, p =.002, d =.549) and hyperactive behavior (ABC-hyperactivity subscale) (t(12) = 3.65, p =.003, d =.686). Moreover, patients rated their own health-related quality of life higher after treatment. At baseline, TSC patients showed several atypical ERPs versus typically developing peers of which prepulse inhibition was significantly decreased in the TSC group. Neuropsychological measurements showed no change and bumetanide had no effect on seizure frequency. Limitations: The sample size and open-label design of this pilot study warrant caution when interpreting outcome measures. Conclusions: Bumetanide treatment is a potential treatment to alleviate the behavioral burden and quality of life associated with TSC. More elaborate trials are needed to determine the application and effect size of bumetanide for the TSC population. Trial registration EU Clinical Trial Register, EudraCT 2016-002408-13 (www.clinicaltrialsregister.eu/ctr-search/trial/2016-002408-13/NL). Registered 25 July 2016
Event-related potentials and use of psychotropic medication in major psychiatric disorders
Background: Attention deficits measured using event-related potentials (ERPs) have been frequently reported in several major psychiatric disorders, e.g. mood disorder (MD), psychotic disorder (PD) and substance use disorder (SUD). However, comparisons between these specific categories are lacking. Here we investigated if electrophysiological parameters of basic information processing are associated with the above-mentioned categories of psychiatric disorders, or instead were associated with general psychopathology. Methods: 579 subjects with MD, PD or SUD and healthy controls (HC) were included. Participants were tested in a passive auditory and an active visual oddball paradigm to assess mismatch negativity (MMN), P3A and P3B amplitudes. Additionally, we examined associations between these measures and psychoactive medication treatments. Results: All patients had significantly lower P3B amplitudes compared to healthy controls, while only SUD patients had lower P3A amplitudes than MD, PD and HC. PD patients also produced significantly less MMN than both MD and SUD patients. Additionally, we found significantly higher P3B amplitude in HC compared to patients without psychopharmacological treatment and patients treated with two or more psychoactive compounds (polypharmacy), but no significant associations with medication on P3A and MMN amplitudes. Conclusions: Our results add to the theory that P3B deficits are associated with general psychopathology, whereas P3A and MMN deficits appear to be associated with substance abuse and psychotic disorders respectively
Measurement of excitation-inhibition ratio in autism spectrum disorder using critical brain dynamics
cited By 0Balance between excitation (E) and inhibition (I) is a key principle for neuronal network organization and information processing. Consistent with this notion, excitation-inhibition imbalances are considered a pathophysiological mechanism in many brain disorders including autism spectrum disorder (ASD). However, methods to measure E/I ratios in human brain networks are lacking. Here, we present a method to quantify a functional E/I ratio (fE/I) from neuronal oscillations, and validate it in healthy subjects and children with ASD. We define structural E/I ratio in an in silico neuronal network, investigate how it relates to power and long-range temporal correlations (LRTC) of the network's activity, and use these relationships to design the fE/I algorithm. Application of this algorithm to the EEGs of healthy adults showed that fE/I is balanced at the population level and is decreased through GABAergic enforcement. In children with ASD, we observed larger fE/I variability and stronger LRTC compared to typically developing children (TDC). Interestingly, visual grading for EEG abnormalities that are thought to reflect E/I imbalances revealed elevated fE/I and LRTC in ASD children with normal EEG compared to TDC or ASD with abnormal EEG. We speculate that our approach will help understand physiological heterogeneity also in other brain disorders.Peer reviewe
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