Limited Consistency and Strength of Neural Oscillations During Sustained Visual Attention in Schizophrenia.

BACKGROUND: Neural oscillations support perception, attention, and higher-order decision making. Aberrations in the strength or consistency of these oscillations in response to stimuli may underlie impaired visual perception and attention in schizophrenia. Here, we examined the phase and power of alpha oscillations (8-12 Hz) as well as aspects of beta and theta frequency oscillations during a demanding visual sustained attention task. METHODS: Patients with schizophrenia (n = 74) and healthy control participants (n = 68) completed the degraded stimulus continuous performance task during electroencephalography. We used time-frequency analysis to evaluate the consistency (intertrial phase coherence) of the alpha cycle shortly after stimulus presentation (50-250 ms). For oscillation strength, we examined event-related desynchronization in a later window associated with decision making (360-700 ms). RESULTS: Alpha intertrial phase coherence was reduced in schizophrenia, and similar reductions were observed in theta (4-7 Hz) and beta (13-20 Hz), suggesting a lack of responsiveness in slower oscillations to visual stimuli. Alpha and beta event-related desynchronization were also reduced in schizophrenia and associated with worse task performance, increased symptoms, and poorer cognition, suggesting that limited responsiveness of oscillations is related to impairments in the disorder. Individuals with lower intertrial phase coherence had slower resting-state alpha rhythms consistent with dysfunctional oscillations persisting across default and task-related brain states. CONCLUSIONS: In schizophrenia, abnormalities in the phase consistency and strength of slower oscillations during visual perception are related to symptoms and cognitive functioning. Altered visual perception and impaired attention in the disorder may be the consequence of aberrant slower oscillations that fail to dynamically reset and modulate in response to stimuli.

Item response theory-based psychometric analysis of the Short Warwick-Edinburgh Mental Well-Being Scale (SWEMWBS) among adolescents in the UK.

BACKGROUND: Middle and late adolescence is the period in a person's life that is most vulnerable to mental health problems. To enable an evidence base that can support policies to prevent such problems, it is crucial to have good quality, reliable, and accurate measurement tools for mental well-being. One of them is the Short Warwick-Edinburgh Mental Well-Being Scale (SWEMWBS). This study aimed to test the psychometric properties of the SWEMWBS on a large sample of adolescents aged 16 to 19 from the United Kingdom (UK) (N = 8,090). Data were from four waves of the longitudinal panel study Understanding Society. METHODS: The analysis was conducted using Item Response Theory (IRT), which is the most appropriate method for testing psychometric properties. The Graded Response Model (GRM) was applied to the data. The reliability and criterion validity of the SWEMWBS were also examined. RESULTS: The presented results confirm the very good psychometric properties of the SWEMWBS amongst adolescents aged 16 to 19 years. The assumptions for the use (unidimensionality, local non-independence, monotonicity) of IRT were met. The results of GRM showed very high discriminant power for all items. The five-category response scale performed optimally; however, differences were found between points on the response scale both between and within items. In general, the scale as a whole showed very good functioning, but particularly in the negative values of mental well-being. CONCLUSIONS: The SWEMWBS was confirmed as a concise, reliable, and valid instrument for measuring mental well-being among older UK adolescents.

Neural indicators of initial control rather than early maintenance of attention predict impaired visual attention in schizophrenia.

Attentional filtering has long been suggested to be a core deficit of schizophrenia. Recent work has emphasized the important distinction between attentional control, which involves the voluntary selection of a particular stimulus for focused processing, and implementation of selection, which involves the mechanisms that actually enhance the stimulus selected via filtering processes. We recorded electroencephalography data from people with schizophrenia (PSZ), their first-degree relatives (REL) and healthy controls (CTRL) during performance of a resistance to attentional capture task that tapped attentional control and implementation of selection measured during a brief period of attentional maintenance. Event-related potentials (ERPs) during attentional control and maintenance of attention revealed diminished neural responding in PSZ. ERPs during attentional control predicted performance on the visual attention task for PSZ, but not for REL and CTRL. Visual attention performance for CTRL was best predicted by ERPs during attentional maintenance. These results support the idea that poor initial voluntary attentional control is more central to attentional dysfunction in schizophrenia than difficulty implementing selection (e.g., maintaining attention). Nevertheless, weak neural modulations indicative of impaired early attentional maintenance in PSZ challenge notions of increased intensity of focus or "hyperfocusing" in the disorder. Improvement of the initial control of attention may be a productive target for cognitive remediation interventions for schizophrenia. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Individual alpha peak frequency is slower in schizophrenia and related to deficits in visual perception and cognition.

The brain at rest generates cycles of electrical activity that have been shown to be abnormal in people with schizophrenia. The alpha rhythm (~ 10 Hz) is the dominant resting state electrical cycle and each person has a propensity toward a particular frequency of oscillation for this rhythm. This individual alpha peak frequency (IAPF) is hypothesized to be central to visual perceptual processes and may have downstream influences on cognitive functions such as attention, working memory, or problem solving. In the current study we sought to determine whether IAPF was slower in schizophrenia, and whether lower IAPF predicted deficits in visual perception and cognition that are often observed in schizophrenia. Eyes-closed resting state EEG activity, visual attention, and global cognitive functioning were assessed in individuals with schizophrenia (N = 104) and a group of healthy controls (N = 101). Compared to controls, the schizophrenia group showed slower IAPF and was associated with poorer discrimination of visual targets and nontargets on a computerized attention task, as well as impaired global cognition measured using neuropsychological tests across groups. Notably, disruptions in visual attention fully mediated the relationship between IAPF and global cognition across groups. The current findings demonstrate that slower alpha oscillatory cycling accounts for global cognitive deficits in schizophrenia by way of impairments in perceptual discrimination measured during a visual attention task.

Paralytic ileus precipitating platypnoea-orthodeoxia after right pneumonectomy.

A 78-year-old female underwent a right pneumonectomy for a neuroendocrine tumour. In the early postoperative phase, she developed a paralytic ileus and went on to develop breathlessness and orthostatic desaturation, which characterizes platypnoea-orthodeoxia. She was found to have an intra-atrial shunt on bubble echo, with equal atrial pressures. This was managed by device closure of the atrial connection, following which her condition improved.

Applying Prospect Theory to Participation in a CAPI/Web Panel Survey.

Prospect theory states that the influential power of avoiding negative outcomes is stronger than that of achieving positive outcomes. In a survey context, this theory has been tested with respect to not only participation in a CATI survey, but also giving consent to data linkage in CATI surveys. No study, however, has tested the theory with respect to participation in a CAPI or web survey. This study does so in a mixed-mode panel context; it also tests the moderating effects of time-in-panel, response history, and mode protocol. Results show that the framing of the survey participation request influences participation propensity in a way consistent with prospect theory, but only for relatively recent panel entrants. The opposite effect is found for long-term panel participants. No difference is found between mode protocols.

Can targeted cover letters improve participation in health surveys? Results from a randomized controlled trial.

BACKGROUND: Improving response rates in epidemiologic studies is important for the generalizability of the outcome. The aim of this study was to examine whether it can be advantageous for participation to target different versions of the cover letters to different sample subgroups. METHODS: A randomized trial was incorporated in a cross-sectional health survey in Denmark (n = 25,000) where a motivational sentence in the cover letter intended to heighten perceptions of relevance of the survey was varied among 11 sample subgroups (treatment groups). Ten different versions of a sentence outlining questionnaire themes were tested: each mentioned three out of five themes: stress, alcohol, sex, sleep problems, and contact with family and friends. An eleventh group, the control group, omitted this sentence. RESULTS: On average, the additional motivational sentence resulted in a significantly lower response rate overall compared to the control group. However, the additional motivational sentence was found to have heterogeneous effects on survey response. Furthermore, the nature of the heterogeneity differed between the versions of the sentence. Specifically, the additional sentence tended to produce a higher response rate among the youngest age group and a lower response rate in the oldest age group compared to the generic letter. The use of alcohol in the motivational sentence tended to have a positive effect on response in the age group 16-24 years, and stress tended to have a positive effect in the age group ≥65 years. On the contrary, sex tended to have a negative effect in the age groups 45-64 years and ≥ 65 years. However, a significant interaction was only found between the use of stress and age group (p = < 0.0001). CONCLUSION: The findings of significant and heterogeneous effects suggest that there is potential for a targeted approach to improve both response rates and sample composition. The uneven effect of the separate themes across age groups suggests that the selection of themes to be included in the motivational sentence is important for the use of targeted appeals to be successful and warrants further research to better identify which themes works in which contexts, in which subgroups and under which circumstances. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03046368 , retrospectively registered February 8th, 2017.

Aortic valve endocarditis with root abscess causing superior vena cava obstruction: a case report.

BACKGROUND: To our knowledge, we report the first case of endocarditis with root abscess causing compressive superior vena cava (SVC) obstruction. CASE SUMMARY: An 84-year-old gentleman with previous tissue aortic valve replacement presented with fevers and systemic upset. Blood cultures grew Streptococcus anginosus and transoesophageal echocardiogram identified prosthetic valve vegetations with an associated root abscess. Antibiotics were commenced and referral made for surgical consideration. Several days into treatment the patient developed clinical signs of SVC obstruction and computed tomography demonstrated an enlarging root abscess with SVC compression. The patient was discussed with local cardiothoracic centres, but surgery was not an option primarily due to abscess size and vascular involvement. Priority moved from active to palliative treatment given no improvement with antibiotics, unsuitability for surgery, and patient discomfort. Within several weeks, symptoms/signs of SVC obstruction actually improved, likely due to collateral venous circulation formation and the patient was discharged home with palliative care input. DISCUSSION: There are previous reports of SVC obstruction related to infected SVC thrombus, indwelling intravascular devices, and para-aortic abscess, but none related to infective endocarditis. Streptococcus anginosus endocarditis is rare but often associated with abscess formation, and male gender, increasing age, and previous surgery are recognized risk factors.

Impaired retrieval processes evident during visual working memory in schizophrenia.

Prominent working memory (WM) deficits have been observed in people with schizophrenia (PSZ) across multiple sensory modalities, including the visuospatial realm. Electrophysiological abnormalities noted during early visual processing as well as later cognitive functions in PSZ may underlie deficiencies in WM ability, though the mechanisms linking behavior to neural responses are not well understood. WM dysfunction has also been observed in biological relatives of PSZ (REL) and therefore may be a manifestation of genetic liability for the disorder. We administered a delayed response visuospatial WM task to 23 PSZ, 30 of their REL, and 37 healthy controls (CTRL) to better understand the contributions of neural abnormalities to WM performance deficits associated with schizophrenia. PSZ performed more poorly on the WM task and failed to effectively process distractor stimuli as well as CTRL and REL. N1 electrophysiological responses to probes during retrieval differentiated the type and locations of stimuli presented during encoding in CTRL. Retrieval N1 responses in PSZ, however, failed to do so, while retrieval responses in REL showed more pronounced differentiation of stimulus features during encoding. Furthermore, neural responses during retrieval predicted behavioral performance in PSZ and REL, but not CTRL. These results suggest that retrieval processes are particularly important to efficient visuospatial WM function in PSZ and REL, and support further investigation of WM retrieval as a potential target for improving overall WM function through clinical intervention.