Introduction: Evidence highlights the importance of social isolation as a critical yet underserved treatment target for individuals managing psychosis. Schizotypal traits represent a useful model of psychosis, facilitating the assessment of contributors to social isolation without the confounds associated with schizophrenia. This study utilised structural equation modelling to examine the unique predictive capacity of schizotypal traits for subjective and objective indices of social isolation.
View Article and Find Full Text PDFIn schizophrenia, a disorder associated with N-methyl-D-aspartate receptor (NMDAR) hypofunction, auditory cortical plasticity deficits have been indexed by the synchronized electroencephalographic (EEG) auditory steady-state gamma-band (40-Hz) response (ASSR) and the early auditory evoked gamma-band response (aeGBR), both considered to be target engagement biomarkers for NMDAR function, and potentially amenable to treatment by NMDAR modulators. As transcranial direct current stimulation (tDCS) is likely dependent on NMDAR neurotransmission, this preliminary study, conducted in 30 healthy volunteers, assessed the off-line effects of prefrontal anodal tDCS and sham (placebo) treatment on 40-Hz ASSR and aeGBR. Anodal tDCS failed to alter aeGBR but increased both 40-Hz ASSR power, as measured by event-related spectral perturbations (ERSP), and phase locking, as measured by inter-trial phase consistency (ITPC).
View Article and Find Full Text PDFEvidence suggests that theory of mind (TOM) and social perception (SP) may be impaired within bipolar disorder (BD). However, it remains unclear whether these deficits are facet specific and predictive of functioning. This study assessed the manifestation of TOM and SP in a BD sample.
View Article and Find Full Text PDFThe detection of deviant auditory features is empirically supported as impaired in schizophrenia and has been shown to associate with functional outcome. Modulated by glutamate neurotransmission, this sensory process has also been shown to relate to the α7 nicotinic acetylcholine receptor (nAChR) system, a prioritized molecular target for the development of novel cognition targeted pharmacological treatments. This pilot study assessed the acute effects of CDP-Choline, a choline supplement with α7 nAChR agonist properties, on the mismatch negativity (MMN), an event-related potential index of the detection of an acoustic change, in a sample of individuals diagnosed with chronic schizophrenia.
View Article and Find Full Text PDFDeficient sensory gating (SG) in schizophrenia is associated with functional outcome and offers a therapeutic target as it is linked to the altered function/expression of the α7 nicotinic acetylcholine receptors (nAChRs). This study analyzed the effects of citicoline (CDP-choline), a supplement with α7 nAChRs agonist properties, on SG in a sample of schizophrenia (SZ) patients. Using a randomized, placebo-controlled, double-blind design the dose-dependent (500 mg, 1000 mg, 2000 mg) and baseline-dependent (deficient versus normal suppressors) effects of CDP-choline on SG were examined using the P50 event-related potential (ERP) index of SG.
View Article and Find Full Text PDFSchizophrenia (SZ) is a psychiatric disorder characterized by cognitive dysfunction within the realm of attentional processing. Reduced P3a and P3b event-related potentials (ERPs), indexing involuntary and voluntary attentional processing respectively, have been consistently observed in SZ patients who also express prominent cholinergic deficiencies. The involvement of the brain's cholinergic system in attention has been examined for several decades; however, further inquiry is required to further comprehend how abnormalities in this system affect neighbouring neurotransmitter systems and contribute to neurocognitive deficits.
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