Background: People with schizophrenia (PSZ) are impaired in attentional prioritization of non-salient but relevant stimuli over salient distractors during visual working memory (VWM) encoding. Conversely, guidance of top-down attention by external predictive cues is intact. Yet, it is unknown whether this preserved ability can help PSZ encode more information in the presence of salient distractors.
View Article and Find Full Text PDFBackground: Quick symptomatic remission after the onset of psychotic symptoms is critical in schizophrenia treatment, determining the subsequent disease course and recovery. In this context, only every second patient with acute schizophrenia achieves symptomatic remission within three months of initiating antipsychotic treatment. The potential indication extension of clozapine-the most effective antipsychotic-to be introduced at an earlier stage (before treatment-resistance) is supported by several lines of evidence, but respective clinical trials are lacking.
View Article and Find Full Text PDFPurpose Of Review: Clozapine remains the gold standard for treatment-resistant schizophrenia (TRS). Although the evidence base for its wide-ranging, unique efficacy continues to expand, clozapine remains alarmingly underutilized in industrialized countries. Analyzing the causes and consequences of this problem is crucial for substantially improving the quality of care for TRS patients.
View Article and Find Full Text PDFTher Adv Psychopharmacol
March 2023
Despite its enduring relevance as the single most effective and important evidence-based treatment for schizophrenia, underutilization of clozapine remains considerable. To a substantial degree, this is attributable to a reluctance of psychiatrists to offer clozapine due to its relatively large side-effect burden and the complexity of its use. This underscores the necessity for continued education regarding both the vital nature and the intricacies of clozapine treatment.
View Article and Find Full Text PDFWorld J Biol Psychiatry
November 2023
Objectives: Kynurenine, kynurenic and quinolinic acid are important metabolites in tryptophan metabolism. Due to an involvement in glutamatergic neurotransmission and immune response, previous studies have investigated this pathway in mental disorders such as major depressive disorder (MDD), bipolar disorder (BD) or schizophrenia (SCZ). Tryptophan and kynurenine have been shown to be decreased across disorders, hinting at the missing link how inflammation causes neurotoxicity and psychiatric symptoms.
View Article and Find Full Text PDFStudying the visual system with fMRI often requires using localizer paradigms to define regions of interest (ROIs). However, the considerable interindividual variability of the cerebral cortex represents a crucial confound for group-level analyses. Cortex-based alignment (CBA) techniques reliably reduce interindividual macroanatomical variability.
View Article and Find Full Text PDFObjective: Sensorimotor gating is experimentally operationalized by the prepulse inhibition (PPI) of the startle response (SR). Previous studies suggest high test-retest reliability of PPI and potential correlation with working memory (WM). Here, we aimed to validate and extend the test-retest reliability of PPI in healthy humans and its correlation with WM performance.
View Article and Find Full Text PDFIntroduction: Illuminating neurobiological mechanisms underlying the protective effect of recently discovered common genetic resilience variants for schizophrenia is crucial for more effective prevention efforts. Current models implicate adaptive neuroplastic changes in the visual system and their pro-cognitive effects as a schizophrenia resilience mechanism. We investigated whether common genetic resilience variants might affect brain structure in similar neural circuits.
View Article and Find Full Text PDFNitric oxide (NO) signalling has been implicated in the pathogenesis of several mental illnesses; however, its specific contribution remains unclear. We investigated whether peripheral NO concentration is associated with specific diagnoses, and whether there is a correlation with genetic variation in NO synthase (NOS) genes. We included 185 participants in the study; 52 healthy controls, 43 major depressive disorder (MDD) patients, 41 bipolar disorder (BPD) patients, and 49 schizophrenia (SCZ) patients.
View Article and Find Full Text PDFAim: In specialties that heavily rely on communication skills such as psychiatry, psychotherapy and psychosomatic medicine, teaching in times of the COVID-19 pandemic is especially challenging. In this overview, educators and course directors report their experiences in eteaching and share their innovative solutions.
Methods: We present a collection of methods that relate to teaching and assessment as well as student activation.
Background: Impaired working memory is a core cognitive deficit in both bipolar disorder and schizophrenia. Its study might yield crucial insights into the underpinnings of both disorders on the cognitive and neurophysiological level. Visual working memory capacity is a particularly promising construct for such translational studies.
View Article and Find Full Text PDFIntroduction: In the last century, there have been major changes within the population structure in Germany. The aim of this study was to determine the impact of a changing population structure on identification of familial prostate cancer (PCa), and to investigate how many and which types of other cancers have occurred in patients and their first-degree relatives.
Materials And Methods: A total of 19,540 patients were evaluated in a prospectively collected PCa family database and divided into four birth cohorts: 1925-1934 (cohort A), 1935-1944 (cohort B), 1945-1954 (cohort C), and 1955-1964 (cohort D).
Objective: Despite its numerous side effects, clozapine is still the most effective antipsychotics making it an ideal reference substance to validate the efficacy of novel compounds for the treatment of schizophrenia. However, blood-brain barrier permeability for most new molecular entities is unknown, requiring central delivery. Thus, we performed a dose-finding study for chronic intracerebroventricular (icv) delivery of clozapine in mice.
View Article and Find Full Text PDFMemory impairments are a major characteristic of schizophrenia (SZ). In the current study, we used an associative memory task to test the hypothesis that SZ patients and first-degree relatives have altered functional patterns in comparison to healthy controls. We analyzed the fMRI activation pattern during the presentation of a face-name task in 27 SZ patients, 23 first-degree relatives, and 27 healthy controls.
View Article and Find Full Text PDFEarly exposure to negative environmental impact shapes individual behavior and potentially contributes to any mental disease. We reported previously that accumulated environmental risk markedly decreases age at schizophrenia onset. Follow-up of matched extreme group individuals (≤1 vs.
View Article and Find Full Text PDFBackground: Working memory (WM) deficits in schizophrenia (SCZ) have been linked to impairments in the encoding phase that are associated with aberrant neuronal functioning. Similar abnormalities have been observed in unaffected first-degree relatives (REL) and are thus discussed as candidate endophenotypes. The process of WM consolidation - i.
View Article and Find Full Text PDFThe underlying cellular mechanisms of catatonia, an executive "psychomotor" syndrome that is observed across neuropsychiatric diseases, have remained obscure. In humans and mice, reduced expression of the structural myelin protein CNP is associated with catatonic signs in an age-dependent manner, pointing to the involvement of myelin-producing oligodendrocytes. Here, we showed that the underlying cause of catatonic signs is the low-grade inflammation of white matter tracts, which marks a final common pathway in Cnp-deficient and other mutant mice with minor myelin abnormalities.
View Article and Find Full Text PDFObjective: Working memory (WM) impairments are a prominent neurocognitive symptom in schizophrenia (SZ) and include deficits in memory for serial order and abnormalities in serial position effects (i.e., primacy and recency effects).
View Article and Find Full Text PDFWe tested the effects of variation of stimulus onset asynchrony (SOA) on visual working memory (WM) performance across different load levels and the underlying brain activation patterns using functional magnetic resonance imaging (fMRI) in 48 healthy participants. Participants were instructed to memorise arrays of coloured squares and had to perform a match/non-match judgement on a probe stimulus after a jittered delay. We presented visual pattern masks at four SOAs after the offset of the memory array (100 ms, 200 ms, 400 ms, and 800 ms).
View Article and Find Full Text PDFBehavioral evidence indicates that working memory (WM) in schizophrenia is already impaired at the encoding stage. However, the neurophysiological basis of this primary deficit remains poorly understood. Using event-related fMRI, we assessed differences in brain activation and functional connectivity during the encoding, maintenance and retrieval stages of a visual WM task with 3 levels of memory load in 17 adolescents with early-onset schizophrenia (EOS) and 17 matched controls.
View Article and Find Full Text PDFSchizophrenia is one of the most disabling forms of mental illness. One of the most important challenges is to establish biological markers which can accurately identify at-risk individuals in preclinical stages and thus improve the effects of early intervention strategies. Here, we review recent findings in the field of molecular genetics, CSF (cerebrospinal fluid) based markers as well as structural and functional neuroimaging in the light of their relevance for schizophrenia biomarker research.
View Article and Find Full Text PDFBackground: Working memory (WM) deficits are a core feature of schizophrenia. Recent electrophysiological evidence indicates that the brain systems for visual encoding are especially impaired. However, patients still achieve performance levels clearly above chance, which indicates the existence of residual mechanisms supporting WM encoding.
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