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Relationship of plasma biomarkers to digital cognitive tests in Alzheimer's disease.
INTRODUCTION: A major limitation in Alzheimer's disease (AD) research is the lack of the ability to measure cognitive performance at scale-robustly, remotely, and frequently. Currently, there are no established online digital platforms validated against plasma biomarkers of AD. METHODS: We used a novel web-based platform that assessed different cognitive functions in AD patients (N = 46) and elderly controls (N = 53) who were also evaluated for plasma biomarkers (amyloid beta 42/40 ratio, phosphorylated tau ([p-tau]181, glial fibrillary acidic protein, neurofilament light chain). Their cognitive performance was compared to a second, larger group of elderly controls (N = 352). RESULTS: Patients with AD were significantly impaired across all digital cognitive tests, with performance correlating with plasma biomarker levels, particularly p-tau181. The combination of p-tau181 and the single best-performing digital test achieved high accuracy in group classification. DISCUSSION: These findings show how online testing can now be deployed in patients with AD to measure cognitive function effectively and related to blood biomarkers of the disease. HIGHLIGHTS: This is the first study comparing online digital testing to plasma biomarkers.Alzheimer's disease patients and two independent cohorts of elderly controls were assessed.Cognitive performance correlated with plasma biomarkers, particularly phosphorylated tau (p-tau)181.Glial fibrillary acidic protein and neurofilament light chain, and less so the amyloid beta 42/40 ratio, were also associated with performance.The best cognitive metric performed at par to p-tau181 in group classification.
Generalization of auditory expertise in audio engineers and instrumental musicians.
From auditory perception to general cognition, the ability to play a musical instrument has been associated with skills both related and unrelated to music. However, it is unclear if these effects are bound to the specific characteristics of musical instrument training, as little attention has been paid to other populations such as audio engineers and designers whose auditory expertise may match or surpass that of musicians in specific auditory tasks or more naturalistic acoustic scenarios. We explored this possibility by comparing students of audio engineering (n = 20) to matched conservatory-trained instrumentalists (n = 24) and to naive controls (n = 20) on measures of auditory discrimination, auditory scene analysis, and speech in noise perception. We found that audio engineers and performing musicians had generally lower psychophysical thresholds than controls, with pitch perception showing the largest effect size. Compared to controls, audio engineers could better memorise and recall auditory scenes composed of non-musical sounds, whereas instrumental musicians performed best in a sustained selective attention task with two competing streams of tones. Finally, in a diotic speech-in-babble task, musicians showed lower signal-to-noise-ratio thresholds than both controls and engineers; however, a follow-up online study did not replicate this musician advantage. We also observed differences in personality that might account for group-based self-selection biases. Overall, we showed that investigating a wider range of forms of auditory expertise can help us corroborate (or challenge) the specificity of the advantages previously associated with musical instrument training.
Sustained pupil responses are modulated by predictability of auditory sequences
The brain is highly sensitive to auditory regularities and exploits the predictable order of sounds in many situations, from parsing complex auditory scenes, to the acquisition of language. To understand the impact of stimulus predictability on perception, it is important to determine how the detection of predictable structure influences processing and attention. Here we use pupillometry to gain insight into the effect of sensory regularity on arousal. Pupillometry is a commonly used measure of salience and processing effort, with more perceptually salient or perceptually demanding stimuli consistently associated with larger pupil diameters. In two experiments we tracked human listeners’ pupil dynamics while they listened to sequences of 50ms tone pips of different frequencies. The order of the tone pips was either random, contained deterministic (fully predictable) regularities (experiment 1, n = 18, 11 female) or had a probabilistic regularity structure (experiment 2, n = 20, 17 female). The sequences were rapid, preventing conscious tracking of sequence structure thus allowing us to focus on the automatic extraction of different types of regularities. We hypothesized that if regularity facilitates processing by reducing processing demands, a smaller pupil diameter would be seen in response to regular relative to random patterns. Conversely, if regularity is associated with heightened arousal and attention (i.e. engages processing resources) the opposite pattern would be expected. In both experiments we observed a smaller sustained (tonic) pupil diameter for regular compared with random sequences, consistent with the former hypothesis and confirming that predictability facilitates sequence processing.
Dissociable behavioural signatures of co-existing impulsivity and apathy in decision-making.
Apathy and impulsivity are expressed in a wide range of neuropsychiatric disorders, and, to a less severe extent, in healthy people too. Although traditionally considered to be opposite extremes of a single motivational spectrum, recent epidemiological questionnaire-based data suggest that both traits can in fact co-exist within the same individual. Here, we sought to investigate the relationship between these constructs in healthy people within a controlled task environment that examines the ability to make a decision under temporal uncertainty and measures the vigour of the response. Sixty participants performed a new version of the Traffic Light Task and completed self-report questionnaire measures of apathy and impulsivity. The task required individuals to make rapid decision-making for time-sensitive reward by squeezing a hand-held dynamometer as quickly as possible after a predictable event occurred (a traffic light turning green). Although apathy and impulsivity were positively correlated in questionnaire assessments, the two traits were associated with distinct behavioural signatures on the task. Impulsivity was expressed as an inflexible tendency to generate rapid anticipatory responses, regardless of cost-benefit information. Apathy, on the other hand, was associated with a blunted effect of reward on response vigour. These findings reveal how apathy and impulsivity are related to distinct dimensions of goal-directed behaviour, explaining how these traits might co-exist in the same individuals.
Cognitive behavioural therapy for sleep problems in psychosis: systematic review of effectiveness and acceptability.
BACKGROUND: Sleep problems are common among people with psychosis. Research suggests poor sleep is causally related to psychosis, anxiety and depression. AIMS: This review investigates the effectiveness and acceptability of cognitive-behavioural therapy (CBT) in targeting sleep problems in people with and at risk of psychosis. METHOD: Four databases were searched in line with PRISMA guidelines. Eligible studies either evaluated (a) CBT targeting sleep problems in people with or at risk of psychosis, or (b) subjective experiences of this treatment. Articles not published in peer-review journals were excluded. Treatment effectiveness was investigated for sleep, psychosis and other clinical outcomes. Acceptability was evaluated using qualitative data, drop-out rates, adverse events and relevant questionnaires. Adaptations to standard treatment protocols were described. Research quality was appraised using Cochrane Risk of Bias tools for randomised and non-randomised trials, and a checklist was developed for qualitative papers. RESULTS: Of the 975 records identified, 14 were eligible. The most common CBT target was insomnia. Treatment protocols were typically adapted by omitting sleep restriction. Large effect sizes were reported for sleep outcomes; however, effects for other clinical outcomes were less clear. Qualitative data and acceptability outcomes suggest that treatment was received positively by participants. CONCLUSIONS: CBT is an effective and acceptable treatment for sleep problems in people with and at risk of psychosis. However, our conclusions are limited by few good-quality studies and small samples. Further gold-standard research is required to inform evidence-based guidelines.
What do people do in the aftermath of healthcare-related harm? A qualitative study on experiences and factors influencing decision-making.
OBJECTIVES: To capture experiences of people self-reporting harm and contrast responses and actions between those who do or do not take formal action. DESIGN: Semi-structured qualitative interview study. SETTING: People self-reporting harm experienced in the National Health Service (NHS) or their family/friends identified from a general Great British population survey. PARTICIPANTS: 49 participants. RESULTS: There were commonalities in experiences after harm whether formal action (including making a formal complaint or litigation) was taken or not. Many participants reported raising concerns informally with NHS staff, trying to access explanations or support, but were usually unsuccessful. Decision-making on action was complex. There were multiple reasons for not pursuing formal action, including fears of damaging relationships with clinicians, being occupied coping with the consequences of the harm or not wanting to take action against the NHS. NHS advocacy services were not regarded as helpful. Knowledge of how to proceed and feeling entitled to do so, along with proactive social networks, could facilitate action, but often only after people were spurred on by anger and frustration about not receiving an explanation, apology or support for recovery from the NHS. Those from marginalised groups were more likely to feel disempowered to act or be discouraged by family or social contacts, which could lead to self-distancing and reduced trust in services. CONCLUSIONS: People actively seek resolution and recovery after harm but often face multiple barriers in having their needs for explanations, apologies and support addressed. Open and compassionate engagement, especially with those from more marginalised communities, plus tailored support to address needs, could promote recovery, decrease compounded harm and reduce use of grievance services where other provision may be more helpful.
Research assistants’ experiences recruiting patients with psychosis into clinical trials: a qualitative study
Abstract Objectives Treatments for patients diagnosed with psychosis need to be improved. Clinical trials are an important way of assessing the efficacy of new treatments. However, recruiting patients into trials is challenging. This study sought to better understand the reasons for this from the perspective of research assistants. Design A qualitative study underpinned by a critical realist ontology and contextualist epistemology. Methods Research assistants who had recruited patients with psychosis into trials, primarily of psychological interventions, were interviewed. Reflexive thematic analysis was used to identify themes. Results Overarching themes representing four types of factors influencing recruitment of patients with psychosis into clinical trials were generated: patient, clinical team, research team, and NHS infrastructure. Patients largely wished to take part in trials but needed time to build trust with research assistants. Clinical teams held the power in suggesting patients for trials; therefore, it was essential for research teams to build strong relationships with clinical staff. Research teams recruiting into trials benefited from lived experience expertise, support systems, and institutional knowledge. A key NHS infrastructure factor was that mental health staff had limited time to consider trials for their patients. Conclusions Trial participation needs to be made more accessible to patients with psychosis, who often want to take part but lack opportunities. Methods of increasing accessibility could include identifying and addressing barriers to referral from clinical teams, employing multiple recruitment strategies, and flexible appointment formats. Qualitative research with clinical teams and patients will also help in developing the understanding of barriers to recruitment.
Dynamic off-resonance correction improves functional image analysis in fMRI of awake behaving non-human primates.
INTRODUCTION: Use of functional MRI in awake non-human primate (NHPs) has recently increased. Scanning animals while awake makes data collection possible in the absence of anesthetic modulation and with an extended range of possible experimental designs. Robust awake NHP imaging however is challenging due to the strong artifacts caused by time-varying off-resonance changes introduced by the animal's body motion. In this study, we sought to thoroughly investigate the effect of a newly proposed dynamic off-resonance correction method on brain activation estimates using extended awake NHP data. METHODS: We correct for dynamic B0 changes in reconstruction of highly accelerated simultaneous multi-slice EPI acquisitions by estimating and correcting for dynamic field perturbations. Functional MRI data were collected in four male rhesus monkeys performing a decision-making task in the scanner, and analyses of improvements in sensitivity and reliability were performed compared to conventional image reconstruction. RESULTS: Applying the correction resulted in reduced bias and improved temporal stability in the reconstructed time-series data. We found increased sensitivity to functional activation at the individual and group levels, as well as improved reliability of statistical parameter estimates. CONCLUSIONS: Our results show significant improvements in image fidelity using our proposed correction strategy, as well as greatly enhanced and more reliable activation estimates in GLM analyses.
Analysing the effect of early acetazolamide administration on patients with a high risk of permanent cerebrospinal fluid leakage.
In this study, we examined the role of early acetazolamide administration in reducing the risk of cerebrospinal fluid (CSF) leakage in patients with a high risk of permanent CSF leakage. In a randomised clinical trial, 57 patients with a high risk of permanent CSF leakage (rhinorrhea, otorrhea, pneumatocele or imaging-based evidence of severe skull-base fracture) were analysed. In the experimental group, acetazolamide, at 25 mg/kg/day, was started in the first 48 hours after admission. In the control group, acetazolamide was administered after the first 48 hours at the same dose administered to the patients in the experimental group. The following factors were compared between the two groups: duration of CSF leakage, duration of hospital stay, incidence of meningitis, need for surgical intervention and need for lumbar puncture (LP) and lumbar drainage (LD). All of the patients in the experimental group stopped having CSF leakage less than 14 days after the first day of admission, but 6 out of 21 patients (22%) in the control group continued having CSF leakage after 14 days of admission, which was a significant difference (P=0.01). This study showed that early acetazolamide administration can prevent CSF leakage in patients with a high risk of permanent CSF leak.
A 12-year epidemiologic study on primary spinal cord tumors in Isfahan, Iran.
BACKGROUND: Although primary spinal cord tumors (PSCTs) comprise a minority of primary central nervous system tumors, they often impose a great deal of morbidity on their victims. Few epidemiologic studies have addressed PSCTs in Iran. MATERIALS AND METHODS: We analyzed the demographic/clinical features of all primary intraspinal tumors (with a specific focus on primary intradural spinal cord tumors) identified between 1992 and 2004 in three of the major related hospitals in Isfahan, Iran. We also tracked the malignant cases until 2012. RESULTS: 102 patients with primary intraspinal tumors were found; 82 tumors were Intradural (36 intramedullary and 46 extramedullary) and 20 extradural. The principal intradural histological subtypes were nerve sheath tumor (33%), ependymoma (22%), astrocytoma (16%), and meningioma (15%). 20 (19%) of the tumors were malignant. Local pain (43%) and motor disabilities (36%) were the most common first-presenting symptoms in the patients. Male-to-female ratio was significant only in ependymoma (male:female ratio = 3.6, P < 0.05). The mean age in meningioma (57 years, standard error [SE]: 15.7) was significantly higher than other types (one-way ANOVA, P < 0.05). CONCLUSION: Our results reflect analogous frequency of distribution for PSCTs compared with most of the previous counterpart studies worldwide. The only notable exception was the comparatively fewer frequency of spinal cord meningioma in our study.
The Nuffield Early Language Intervention (NELI) programme is associated with lasting improvements in children's language and reading skills.
BACKGROUND: Oral language skills are a critical foundation for education and psychosocial development. Learning to read, in particular, depends heavily on oral language skills. The Nuffield Early Language Intervention (NELI) has been shown to improve the language of 4-5-year-old children entering school with language weaknesses in four robust trials. To date, however, there is limited evidence on the durability of the gains produced by the intervention, and some have argued that the effects of such educational interventions typically fade-out quite rapidly. METHODS: A large-scale effectiveness trial of the NELI intervention implemented under real-world conditions produced educationally meaningful improvements in children's language and reading abilities. Here, we report follow-up testing of children from this study conducted approximately 2 years after the completion of the intervention. RESULTS: At 2-year follow-up, children who had received NELI had better oral language (d = 0.22 or d = 0.33 for children with lower language ability), reading comprehension (d = 0.16 or d = 0.24 for children with lower language ability) and single-word reading skills (d = 0.16 or d = 0.22 for children with lower language ability) than the control group. CONCLUSIONS: Our data show that, although fade-out effects are common in educational research, a widely used language intervention produces durable improvements in language and reading skills, with educationally important effect sizes. These findings have important theoretical and practical implications.
Comparison of a theoretically driven cognitive therapy (the Feeling Safe Programme) with befriending for the treatment of persistent persecutory delusions: a parallel, single-blind, randomised controlled trial.
BACKGROUND: There is a large clinical need for improved treatments for patients with persecutory delusions. We aimed to test whether a new theoretically driven cognitive therapy (the Feeling Safe Programme) would lead to large reductions in persecutory delusions, above non-specific effects of therapy. We also aimed to test treatment effect mechanisms. METHODS: We did a parallel, single-blind, randomised controlled trial to test the Feeling Safe Programme against befriending with the same therapists for patients with persistent persecutory delusions in the context of non-affective psychosis diagnoses. Usual care continued throughout the duration of the trial. The trial took place in community mental health services in three UK National Health Service trusts. Participants were included if they were 16 years or older, had persecutory delusions (as defined by Freeman and Garety) for at least 3 months and held with at least 60% conviction, and had a primary diagnosis of non-affective psychosis from the referring clinical team. Patients were randomly assigned to either the Feeling Safe Programme or the befriending programme, using a permuted blocks algorithm with randomly varying block size, stratified by therapist. Trial assessors were masked to group allocation. If an allocation was unmasked then the unmasked assessor was replaced with a new masked assessor. Outcomes were assessed at 0 months, 6 months (primary endpoint), and 12 months. The primary outcome was persecutory delusion conviction, assessed within the Psychotic Symptoms Rating Scale (PSYRATS; rated 0-100%). Outcome analyses were done in the intention-to-treat population. Each intervention was provided individually over 6 months. This trial is registered with the ISRCTN registry, ISRCTN18705064. FINDINGS: From Feb 8, 2016, to July 26, 2019, 130 patients with persecutory delusions (78 [60%] men; 52 [40%] women, mean age 42 years [SD 12·1, range 17-71]; 86% White, 9% Black, 2% Indian; 2·3% Pakistani; 2% other) were recruited. 64 patients were randomly allocated to the Feeling Safe Programme and 66 patients to befriending. Compared with befriending, the Feeling Safe Programme led to significant end of treatment reductions in delusional conviction (-10·69 [95% CI -19·75 to -1·63], p=0·021, Cohen's d=-0·86) and delusion severity (PSYRATS, -2·94 [-4·58 to -1·31], p<0·0001, Cohen's d=-1·20). More adverse events occurred in the befriending group (68 unrelated adverse events reported in 20 [30%] participants) compared with the Feeling Safe group (53 unrelated adverse events reported in 16 [25%] participants). INTERPRETATION: The Feeling Safe Programme led to a significant reduction in persistent persecutory delusions compared with befriending. To our knowledge, these are the largest treatment effects seen for patients with persistent delusions. The principal limitation of our trial was the relatively small sample size when comparing two active treatments, meaning less precision in effect size estimates and lower power to detect moderate treatment differences in secondary outcomes. Further research could be done to determine whether greater effects could be possible by reducing the hypothesised delusion maintenance mechanisms further. The Feeling Safe Programme could become the recommended psychological treatment in clinical services for persecutory delusions. FUNDING: NIHR Research Professorship and NIHR Oxford Health Biomedical Research Centre.
Automated virtual reality cognitive therapy versus virtual reality mental relaxation therapy for the treatment of persistent persecutory delusions in patients with psychosis (THRIVE): a parallel-group, single-blind, randomised controlled trial in England with mediation analyses.
BACKGROUND: Persecutory delusions are a major psychiatric problem that often do not respond sufficiently to standard pharmacological or psychological treatments. We developed a new brief automated virtual reality (VR) cognitive treatment that has the potential to be used easily in clinical services. We aimed to compare VR cognitive therapy with an alternative VR therapy (mental relaxation), with an emphasis on understanding potential mechanisms of action. METHODS: THRIVE was a parallel-group, single-blind, randomised controlled trial across four UK National Health Service trusts in England. Participants were included if they were aged 16 years or older, had a persistent (at least 3 months) persecutory delusion held with at least 50% conviction, reported feeling threatened when outside with other people, and had a primary diagnosis from the referring clinical team of a non-affective psychotic disorder. We randomly assigned (1:1) patients to either THRIVE VR cognitive therapy or VR mental relaxation, using a permuted blocks algorithm with randomly varying block size, stratified by severity of delusion. Usual care continued for all participants. Each VR therapy was provided in four sessions over approximately 4 weeks, supported by an assistant psychologist or clinical psychologist. Trial assessors were masked to group allocation. Outcomes were assessed at 0, 2 (therapy mid-point), 4 (primary endpoint, end of treatment), 8, 16, and 24 weeks. The primary outcome was persecutory delusion conviction, assessed by the Psychotic Symptoms Rating Scale (PSYRATS; rated 0-100%). Outcome analyses were done in the intention-to-treat population. We assessed the treatment credibility and expectancy of the interventions and the two mechanisms (defence behaviours and safety beliefs) that the cognitive intervention was designed to target. This trial is prospectively registered with the ISRCTN registry, ISRCTN12497310. FINDINGS: From Sept 21, 2018, to May 13, 2021 (with a pause due to COVID-19 pandemic restrictions from March 16, 2020, to Sept 14, 2020), we recruited 80 participants with persistent persecutory delusions (49 [61%] men, 31 [39%] women, with a mean age of 40 years [SD 13, range 18-73], 64 [80%] White, six [8%] Black, one [1%] Indian, three [4%] Pakistani, and six [8%] other race or ethnicity). We randomly assigned 39 (49%) participants assigned to VR cognitive therapy and 41 (51%) participants to VR mental relaxation. 33 (85%) participants who were assigned to VR cognitive therapy attended all four sessions, and 35 (85%) participants assigned to VR mental relaxation attended all four sessions. We found no significant differences between the two VR interventions in participant ratings of treatment credibility (adjusted mean difference -1·55 [95% CI -3·68 to 0·58]; p=0·15) and outcome expectancy (-0·91 [-3·42 to 1·61]; p=0·47). 77 (96%) participants provided follow-up data at the primary timepoint. Compared with VR mental relaxation, VR cognitive therapy did not lead to a greater improvement in persecutory delusions (adjusted mean difference -2·16 [-12·77 to 8·44]; p=0·69). Compared with VR mental relaxation, VR cognitive therapy did not lead to a greater reduction in use of defence behaviours (adjusted mean difference -0·71 [-4·21 to 2·79]; p=0·69) or a greater increase in belief in safety (-5·89 [-16·83 to 5·05]; p=0·29). There were 17 serious adverse events unrelated to the trial (ten events in seven participants in the VR cognitive therapy group and seven events in five participants in the VR mental relaxation group). INTERPRETATION: The two VR interventions performed similarly, despite the fact that they had been designed to affect different mechanisms. Both interventions had high uptake rates and were associated with large improvements in persecutory delusions but it cannot be determined that the treatments accounted for the change. Immersive technologies hold promise for the treatment of severe mental health problems. However, their use will likely benefit from experimental research on the application of different therapeutic techniques and the effects on a range of potential mechanisms of action. FUNDING: Medical Research Council Developmental Pathway Funding Scheme and National Institute for Health and Care Research Oxford Health Biomedical Research Centre.
Exploring stigma, shame, and safety behaviours in social anxiety and paranoia amongst people diagnosed with schizophrenia.
BACKGROUND: Social anxiety and paranoia are connected by a shared suspicion framework. Based on cognitive-behavioural approaches, there is evidence for treating social anxiety and psychosis. However, mechanisms underlying the relationship between social anxiety and paranoia remain unclear. AIMS: To investigate mediators between social anxiety and paranoia in schizophrenia such as negative social appraisals (i.e. stigma or shame; Hypothesis 1), and safety behaviours (i.e. anxious avoidance or in situ safety behaviours; Hypothesis 2). METHOD: A cross-sectional study was conducted among Asian out-patients with schizophrenia (January-April 2020). Data on social anxiety, paranoia, depression, shame, stigma, anxious avoidance, and in situ behaviours were collected. Associations between social anxiety and paranoia were investigated using linear regressions. Mediation analysis via 10,000 bias-corrected bootstrap samples with 95% confidence intervals (CI) was used to test the indirect effects (ab) of mediators. RESULTS: Participants (n=113, 59.3% male) with a mean age of 44.2 years were recruited. A linear relationship between social anxiety and paranoia was found. In multiple mediation analyses (co-varying for depression), stigma and shame (Hypothesis 1) did not show any significant indirect effects with ab=.004 (95%CI=-.013, .031) and -.003 (-.023, .017), respectively, whereas in situ behaviours (Hypothesis 2) showed a significant effect with ab=.110 (.038, .201) through the social anxiety-paranoia relationship. CONCLUSIONS: Social anxiety and paranoia are positively correlated. In situ safety behaviours fully mediated the social anxiety and paranoia relationship. Targeted interventions focusing on safety behaviours could help reduce paranoia in psychosis. Symptom severity should be measured to help characterise the participants' characteristics.