Cognitive Neuropsychiatry最新文献

Objective: Paranoid ideation underlies numerous psychological disorders and has debilitating effects on daily life. Deficits in neurocognition are highlighted as a contributing factor to paranoid-related disorders, but the impact on the symptom-level experience of paranoid ideation is unclear. This study aimed to employ a dimensional approach to understand the association between neurocognition and the severity and presence of paranoid ideation.

Methods: 400 participants, representative of the general population of the USA, completed an online questionnaire consisting of the Brief Symptom Inventory-53, and demographic and clinical questions. The participants then completed four computerised neurocognitive tasks measuring working memory, shifting, inhibition, and speed of processing.

Results: Speed of processing accounted for unique variance in the severity of paranoid ideation with a small effect size, after controlling for covariates. Working memory, shifting, and inhibition could not uniquely or collectively, account for paranoid ideation. Neurocognitive performance could not distinguish between individuals with and without paranoid ideation experiences.

Conclusions: This research supports the body of literature that speed of information processing may be a key feature of paranoid ideation. Future research should employ non-linear dynamic methods to better understand the potential interactions between neurocognitive components and how this may relate to paranoid ideation.

Introduction: The study aims to use power spectrum changes in subjective cognitive decline (SCD) and amnestic mild cognitive impairment (aMCI), preclinical stages of Alzheimer's disease (AD), for future biomarker studies in early AD diagnosis.

Methods: We recruited 23 SCD and 32 aMCI subjects and conducted comparative analysis using relative power spectral density (PSD). Automated preprocessing and statistical analysis were performed using iSync Brain® (iMediSync Inc., Republic of Korea) (https://isyncbrain.com/).

Results: Theta band power in the temporal region was 14.826 ± 7.2394 for the SCD group and 20.003 ± 10.1768 for the aMCI group. In the parietal region, theta band power was 13.614 ± 7.5689 for SCD and 19.894 ± 11.1387 for aMCI. Beta1 band power in the frontal region was 6.639 ± 2.2904 for SCD and 5.465 ± 1.8907 for aMCI, and in the temporal region it was 7.359 ± 2.5619 for SCD and 5.921 ± 2.1605 for aMCI.

Conclusion: PSD analysis of resting-state EEG predicted SCD, a preclinical stage of AD. This cross-sectional study observed electrical-physiological characteristics of preclinical AD; however, follow-up studies are needed to evaluate predictive value for future cognitive decline.

Introduction: In schizophrenia, social functioning and personal recovery are pivotal outcomes potentially influenced by cognitive biases such as Jumping to Conclusions (JTC). Despite their significance, the relationship between JTC, social functioning, and personal recovery remains unclear. This study aims to investigate this relationship to inform tailored interventions for schizophrenia management.

Methods: Data were collected from 94 schizophrenia patients using standardised measures. The Beads Task assessed JTC, whereas the Brief PANSS, TMT-J, SLOF-J, and RAS-J evaluated psychiatric symptoms, neurocognitive functioning, social functioning, and personal recovery, respectively. Statistical analyses included correlation and hierarchical regression.

Results: Correlation analyses revealed a significant negative correlation between JTC and personal recovery (r = -0.27, p < 0.05). Hierarchical regression indicated JTC as a significant negative predictor of personal recovery (β = -0.33, p = 0.01). No significant correlation was found between JTC and social functioning.

Discussion: Increased JTC was associated with lower levels of personal recovery in schizophrenia patients, independent of demographic and clinical factors. In the case of individuals with schizophrenia who demonstrate JTC, there is a potential to suggest the paradox of insight or apparent personal recovery scores.

Introduction: Schizophrenia and autism spectrum disorder are distinct neurodevelopmental disorders sharing clinically relevant behaviours. However, early sensory responses show divergent responses. Individuals with schizophrenia typically exhibit cortical hypo-excitability whereas individuals with autism show cortical hyperexcitability. Identifying reliable neurobiological differences between the disorders can diminish misdiagnosis and optimise treatments.

Methods: The pattern glare test (PGT) is a simple measure of behavioural hyperexcitability. It measures the number of illusions seen in a static horizontal grating. We collected PGT data from non-clinical adults varying in traits of autism and schizophrenia (schizotypy). 576 undergraduate students completed an online survey consisting of the Schizotypal Personality Questionnaire - Brief Revised, the Autism Spectrum Quotient, and the PGT.

Results: Subclinical autism and schizotypy traits were highly positively correlated. However, only schizotypy scores were significantly predictive of reporting more pattern glare (PG) illusions. When assessing the subcomponents of the schizotypy and autism scores, positive and disorganised schizotypy traits were predictive of reporting more PG illusions. Whereas, subclinical autism factors were not predictive of PG illusions.

Conclusions: High schizotypy performed the PGT in a manner consistent with behavioural hyperexcitability. The PGT distinguished subclinical autistic traits from schizotypy, suggesting potential clinical application.

Introduction: We report an epileptic patient who experienced hallucinatory visual experiences of autobiographical memories from her past. These visual experiences were confined to the lower left quadrant of her visual field.Methods: We carried out a single-case study that used brain-imaging, EEG and behavioural methods to study this patient.Results: We found that this patient had an incomplete left inferior homonymous quadrantanopia due to a lesion of right occipital cortex, and also that she showed neurological abnormalities in right temporal cortex, a region that is part of the brain's autobiographical-memory circuit.Conclusion: We attribute the occurrence of this patient's autobiographical-memory hallucinations to the combination of degraded visual input to right temporal cortex plus hyperexcitability of that region.

Introduction: We investigated the degree of cognitive insight in patients with Alzheimer's Disease (AD) regarding their hallucinations, aiming to elucidate the subjective experiences and perceptions associated with this phenomenon.

Methods: Using a cross-sectional design, we invited both AD patients (n = 31) and their informants to evaluate the occurrence of hallucinations. Degree of cognitive insight was based upon the discrepancy between the patients' and informants' evaluations.

Results: Analysis demonstrated that AD patients rated the occurrence of hallucinations lower than their informants, indicating that patients tended to underestimate the frequency of their hallucinations. The discrepancy between the ratings of patients and informants was negatively correlated with cognitive functioning, suggesting that a greater discrepancy (indicating poorer insight) was associated with lower cognitive functioning in patients.

Discussion: Our findings highlight the deficits in insight into hallucinations among AD patients, specifically indicating that AD patients have limited awareness of their own hallucinations. Furthermore, our findings support the idea that deficits in insight into hallucinations are associated with the progression of AD.

Introduction: Individuals with high schizotypy or schizophrenia exhibit difficulties in distributing their attention across space, leading to a reduction in their "perceptual span" - the extent of visual space that can be attended to at once. In this study, we aim to explore the correlation between schizotypy and perceptual span in a non-clinical sample to investigate whether perceptual span correlates with schizotypy across its range.

Methods: Schizotypy was assessed in fifty-five participants using the Schizotypy Personality Questionnaire (SPQ; Raine, 1991). Participants were required to attend to two dynamic targets displayed in a head-mounted virtual reality display. Perceptual span was estimated as the lateral angle of separation between the two targets beyond which performance in the task dropped to threshold.

Results: Participants with higher schizotypy scores performed significantly worse on the task. Of all the factors associated with schizotypy, the shared variance between Disorganisation and Cognitive/Perceptual Factors was most predictive of task performance.

Conclusion: The results support the hypothesis that schizotypy predicts perceptual span in non-clinical samples. Furthermore, the demonstration of a reduced perceptual span in individuals with higher trait schizotypy shows that variations in an individual's capacity to divide attention across space can be accurately captured using a virtual reality head-mounted display.