Reward-related learning and individual differences

The thesis explored the impact of personality on performance during category learning (CL) tasks, following motivational and reinforcing manipulations. In particular, the thesis explored how motivation and reinforcement affect performance during category learning tasks and, concurrently, the research aspired to clarify how reward sensitivity is modulated by individual differences in personality. According to findings which indicate that dopamine (DA) plays an important role in reward-based learning (Schultz, 1998; 2002), personality traits which may have a DAergic basis were considered. The thesis makes broad reference to the Reinforcement Sensitivity Theory (RST; Gray and McNaughton, 2000) and, in particular, to the Behavioural Activation System (BAS). Indeed, the BAS is believed to involve DAergic midbrain projections and be sensitive to rewards (Pickering and Gray, 2001). Therefore, the personality traits underlying the BAS are believed to have a DAergic nature and, subsequently, determine inter-individual variations in reward sensitivity. A series of behavioural experiments were conducted to explore the relationship between motivation and personality during CL tasks. Moreover, a biologically inspired model was developed to simulate the behavioural data and capture individual differences. The model had a DAergic basis that represented some of the biological mechanisms that underlie procedural learning and that may occur within brain structures thought to be part of the BAS (Gray, 1987). The model was shown to be a useful tool to obtain further insights into the experimental data. Impulsivity was found to mediate procedural learning in a series of studies. Thus according to RST (Gray, 1987), the present research shows that impulsivity might represent the underlying BAS trait. However, contrary to RST, the model indicated that inter-individual variations in procedural learning were dependent on individual's sensitivity to reward prediction error (RPE) signals rather than rewards per se. Finally, the model simulations suggest that category learning under asymmetric payoffs is mediated by both explicit and implicit (i.e. procedural) processes. The implications of these findings are discussed in light of personality theories and in relation to future studies

Developmental motor profile in preschool children with primary stereotypic movement disorder

Aim. Different neuropsychological dysfunctions have been described in children with primary Stereotypic Movement Disorder (SMD), mainly attention or motor coordination problems. Up to now with no study has evaluated psychomotor functions in preschoolers primary SMD. The aim of this observational study was to gather information on the motor profiles of SMD patients in this age range in comparison with typically developing children. Patients and Methods. Twenty-six children (four girls) aged 36 to 76 months (mean= 53 ±10) with primary SMD were assessed by a structured evaluation including the Movement Assessment Battery for Children-Second Edition (MABC-2), the Beery-Buktenica Developmental test of Visual-Motor Integration (VMI), the Repetitive Behaviour Scale-Revised (RBS-R), the Motor Severity Stereotypy Scale (MSSS), and the Child Behaviour Checklist (CBCL). The diagnoses of Intellectual Disability or Autism Spectrum Disorder were exclusion criteria from the study. A comparison group of twenty-seven (four girls) typically developing children without stereotypies aged 36 to 59 months (mean= 48 ±7) was also examined. Results. The MABC-2 total score was lower than 15th percentile in fifteen children with SMD (58%); the worst performances were observed in Balance and Manual Dexterity subtests. The motor coordination score of VMI was lower than 15th percentile in ten children (38%). The majority of the children with low scores at MABC-2 also had low scores at the motor coordination subscale of VMI. MABC-2 standard scores of the clinical group were significantly lower than those of controls on MABC-2 Total, Balance, and Ball Skills subtests. Conclusion. The finding of widespread dysfunction of gross and fine motor abilities in preschoolers with primary SMD seems to delineate a peculiar phenotype and could provide new approaches to the management of this neurodevelopment disorder

Guided graded exercise self-help plus specialist medical care versus specialist medical care alone for chronic fatigue syndrome (GETSET): a pragmatic randomised controlled trial

Background: Graded exercise therapy is an effective and safe treatment for chronic fatigue syndrome, but it is therapist intensive and availability is limited. We aimed to test the efficacy and safety of graded exercise delivered as guided self-help. Methods: In this pragmatic randomised controlled trial, we recruited adult patients (18 years and older) who met the UK National Institute for Health and Care Excellence criteria for chronic fatigue syndrome from two secondary-care clinics in the UK. Patients were randomly assigned to receive specialist medical care (SMC) alone (control group) or SMC with additional guided graded exercise self-help (GES). Block randomisation (randomly varying block sizes) was done at the level of the individual with a computer-generated sequence and was stratified by centre, depression score, and severity of physical disability. Patients and physiotherapists were necessarily unmasked from intervention assignment; the statistician was masked from intervention assignment. SMC was delivered by specialist doctors but was not standardised; GES consisted of a self-help booklet describing a six-step graded exercise programme that would take roughly 12 weeks to complete, and up to four guidance sessions with a physiotherapist over 8 weeks (maximum 90 min in total). Primary outcomes were fatigue (measured by the Chalder Fatigue Questionnaire) and physical function (assessed by the Short Form-36 physical function subscale); both were self-rated by patients at 12 weeks after randomisation and analysed in all randomised patients with outcome data at follow-up (ie, by modified intention to treat). We recorded adverse events, including serious adverse reactions to trial interventions. We used multiple linear regression analysis to compare SMC with GES, adjusting for baseline and stratification factors. This trial is registered at ISRCTN, number ISRCTN22975026. Findings: Between May 15, 2012, and Dec 24, 2014, we recruited 211 eligible patients, of whom 107 were assigned to the GES group and 104 to the control group. At 12 weeks, compared with the control group, mean fatigue score was 19·1 (SD 7·6) in the GES group and 22·9 (6·9) in the control group (adjusted difference −4·2 points, 95% CI −6·1 to −2·3, p<0·0001; effect size 0·53) and mean physical function score was 55·7 (23·3) in the GES group and 50·8 (25·3) in the control group (adjusted difference 6·3 points, 1·8 to 10·8, p=0·006; 0·20). No serious adverse reactions were recorded and other safety measures did not differ between the groups, after allowing for missing data. Interpretation: GES is a safe intervention that might reduce fatigue and, to a lesser extent, physical disability for patients with chronic fatigue syndrome. These findings need confirmation and extension to other health-care settings

Effects of reduced-risk nicotine-delivery products on smoking prevalence and cigarette sales: an observational study

BACKGROUND: It is not currently clear what impact alternative nicotine-delivery products (electronic cigarettes, heated tobacco products and snus) have on smoking rates and cigarette sales. OBJECTIVE: To assess whether access to these products promotes smoking in the population. DESIGN AND DATA SOURCES: We examined associations of alternative nicotine product use and sales with smoking rates and cigarette sales overall, and in different age and socioeconomic groups, and compared smoking prevalence over time in countries with contrasting regulations of these products. For electronic cigarettes, we examined data from countries with historically similar smoking trajectories but differing current electronic cigarette regulations (United Kingdom and United States of America vs. Australia, where sales of nicotine-containing electronic cigarettes are banned); for heated tobacco, we used data from countries with state tobacco monopolies, where cigarette and heated tobacco sales data are available (Japan, South Korea), and for snus we used data from Sweden. ANALYSIS METHODS: We pre-specified dynamic time series analyses to explore associations between use and sales of alternative nicotine-delivery products and smoking prevalence and cigarette sales, and time series analyses to compare trends of smoking prevalence in countries with different nicotine product policies. RESULTS: Because of data and analysis limitations (see below), results are only tentative and need to be interpreted with caution. Only a few findings reached statistical significance and for most results the Bayes factor indicated inconclusive evidence. We did not find an association between rates of smoking and rates of the use of alternative nicotine products. The increase in heated tobacco product sales in Japan was accompanied by a decrease in cigarette sales. The decline in smoking prevalence seems to have been slower in Australia than in the United Kingdom overall, and slower than in both the United Kingdom and the United States of America among young people and also in lower socioeconomic groups. The decline in cigarette sales has also accelerated faster in the United Kingdom than in Australia. LIMITATIONS: Most of the available data had insufficient data points for robust time series analyses. The assumption of our statistical approach that causal interactions are more likely to be detected when longer-term changes are screened out may not apply for short time series and in product interaction scenarios, where short-term fluctuations can be caused by, for example, fluctuations in prosperity or product supplies. In addition, due to dual use, prevalence figures for smoking and alternative product use overlap. The ecological study design limits the causal inferences that can be made. Longer time periods are needed for any effects of exclusive use of the new products on smoking prevalence to emerge. CONCLUSIONS: We detected some indications that alternative nicotine products are competing with cigarettes rather than promoting smoking and that regulations that allow their sales are associated with a reduction rather than an increase of smoking, but the findings are inconclusive because of insufficient data points and issues with the assumptions of the pre-specified statistical analyses. FUTURE WORK: As further prevalence and sales data emerge the analyses will become more informative. Accessing sales figures in particular is the current research priority. STUDY REGISTRATION: The project is registered on Open Science Framework https://osf.io/bd3ah. FUNDING: This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (NIHR129968) and will be published in full in Public Health Research; Vol. 11, No. 7. See the NIHR Journals Library website for further project information

Evaluation of a positive psychotherapy group intervention for people with psychosis: pilot randomised controlled trial

Aims. Third-wave psychological interventions have gained relevance in mental health service provision but their application to people with psychosis is in its infancy and interventions targeting wellbeing in psychosis are scarce. This study tested the feasibility and preliminary effectiveness of positive psychotherapy adapted for people with psychosis (WELLFOCUS PPT) to improve wellbeing. Methods. WELLFOCUS PPT was tested as an 11-week group intervention in a convenience sample of people with psychosis in a single centre randomised controlled trial (ISRCTN04199273) involving 94 people with psychosis. Patients were individually randomised in blocks to receive either WELLFOCUS PPT in addition to treatment as usual (TAU), or TAU only. Assessments took place before randomisation and after the therapy. The primary outcome was wellbeing (Warwick-Edinburgh Mental Well-Being Scale, WEMWBS). Secondary outcomes included symptoms (Brief Psychiatric Rating Scale), depression (Short Depression-Happiness Scale), self-esteem, empowerment, hope, sense of coherence, savouring beliefs and functioning, as well as two alternative measures of wellbeing (the Positive Psychotherapy Inventory and Quality of Life). Intention-to-treat analysis was performed. This involved calculating crude changes and paired-sample t-tests for all variables, as well as ANCOVA and Complier Average Causal Effect (CACE) Analysis to estimate the main effect of group on all outcomes. Results. The intervention and trial procedures proved feasible and well accepted. Crude changes between baseline and follow-up showed a significant improvement in the intervention group for wellbeing according to all three concepts assessed (i.e., WEMWBS, Positive Psychotherapy Inventory and Quality of Life), as well as for symptoms, depression, hope, self-esteem and sense of coherence. No significant changes were observed in the control group. ANCOVA showed no main effect on wellbeing according to the primary outcome scale (WEMWBS) but significant effects on symptoms (p = 0.006, ES = 0.42), depression (p = 0.03, ES = 0.38) and wellbeing according to the Positive Psychotherapy Inventory (p = 0.02, ES = 0.30). Secondary analysis adapting for therapy group further improved the results for symptom reduction (p = 0.004, ES = 0.43) and depression (p = 0.03, ES = 0.41) but did not lead to any more outcomes falling below the p = 0.05 significance level. CACE analysis showed a non-significant positive association between the intervention and WEMWBS scores at follow-up (b = 0.21, z = 0.9, p = 0.4). Conclusions. This study provides initial evidence on the feasibility of WELLFOCUS PPT in people with psychosis, positively affecting symptoms and depression. However, more work is needed to optimise its effectiveness. Future research might evaluate positive psychotherapy as a treatment for comorbid depression in psychosis, and consider alternative measurements of wellbeing

Development and evaluation of an Individualised Outcome Measure (IOM) for randomised controlled trials in mental health

Predefined, researcher-selected outcomes are routinely used as the clinical end-point in randomised controlled trials (RCTs); however, individualised approaches may be an effective way to assess outcome in mental health research. The present study describes the development and evaluation of the Individualised Outcome Measure (IOM), which is a patient-specific outcome measure to be used for RCTs of complex interventions. IOM was developed using a narrative review, expert consultation and piloting with mental health service users (n=20). The final version of IOM comprises two components: Goal Attainment (GA) and Personalised Primary Outcome (PPO). For GA, patients identify one relevant goal at baseline and rate its attainment at follow-up. For PPO, patients choose an outcome domain related to their goal from a predefined list at baseline, and complete a standardised questionnaire assessing the chosen outcome domain at baseline and follow-up. A feasibility study indicated that IOM had adequate completion (89%) and acceptability (96%) rates in a clinical sample (n=84). IOM was then evaluated in an RCT (ISRCTN02507940). GA and PPO components were associated with each other and with the trial primary outcome. The use of the PPO component of IOM as the primary outcome could be considered in future RCTs

Impact of Barrett oesophagus diagnoses and endoscopies on oesophageal cancer survival in the UK: A cohort study.

BACKGROUND: Current guidelines recommend endoscopic surveillance for Barrett oesophagus (BE), but the value of surveillance is still debated. Using a combination of primary care, secondary care and cancer registry datasets, we examined the impact of a prior BE diagnosis, clinical and risk factors on survival from oesophageal cancer and adenocarcinoma. METHODS: Retrospective cohort study of patients aged 50 and above diagnosed with malignant oesophageal cancer between 1993 and 2014 using Clinical Practice Research Datalink (CPRD). All prior BE diagnoses and endoscopies were identified from CPRD and Hospital Episode Statistics. Histology information was obtained from linked cancer registry data. We used flexible parametric models to estimate excess hazard ratios (EHRs) for relative survival. We simulated the potential impact of lead-time by adding random lead-times from a variety of distributions to all those with prior BE. RESULTS: Among our oesophageal cancer (n = 7503) and adenocarcinoma (n = 1476) cohorts only small percentages, 3.4% and 5.3%, respectively, had a prior BE diagnosis. Two-year relative survival was better among patients with BE: 48.0% (95% CI 41.9-54.9) compared to 25.2% (24.3-26.2) without. Patients with BE had a better prognosis (EHR = 0.53, 0.41-0.68). Survival was higher even if patients with BE had fewer than two endoscopies (50.0%; 43.6-57.3). A survival benefit was still observed after lead-time adjustment, with a 20% absolute difference in 2-year survival using a 5 year mean sojourn time. CONCLUSIONS: Patients with a prior BE diagnosis had a survival advantage. This was not fully explained by surveillance endoscopies

A national survey of recovery practice in community mental health teams

Background There is a policy and professional consensus about the importance of ‘recovery’ in mental health services, but the link between recovery-orientation of mental health teams and personal recovery of service users has been under-researched. Aims To investigate differences in team leader, clinician and service user perspectives of recovery orientation of community adult mental health teams in England. Objectives: (1) To compare variations between NHS Trust, team type and participant ratings of recovery-orientation of mental health teams; (2) To explore the relationship between service user ratings of recovery orientation and personal recovery; (3) To test the hypothesis that clinician-rated recovery orientation differs between clinicians with and without personal experience of mental illness or supporting a family member or friend with mental illness. Method In six English Mental Health NHS Trusts (purposively sampled to maximise geographic and demographic spread), randomly-chosen community adult mental health teams were surveyed. A random sample of ten service users, one team leader and a convenience sample of five clinicians were surveyed from each team. All respondents rated the recovery orientation of their team using parallel versions of the Recovery Self Assessment (RSA). In addition, service users also rated their own personal recovery using Questionnaire about Processes of Recovery (QPR). Results Team leaders (n=22) rated recovery orientation higher than clinicians (n=109) or service users (n=120) (Wald(7)=7.0, p=0.03), and both NHS Trust and team type influenced RSA ratings. Service user-rated recovery orientation was a predictor of personal recovery (b=0.52, p &lt;.001; 95%CI: .31 to .74). Team leaders and clinicians with experience of mental illness (39%) or supporting a family member or friend with mental illness (76%) did not differ in their RSA ratings from other team leaders or clinicians. Conclusions Compared with team leaders, frontline clinicians and service users have less positive views on recovery orientation. Increasing recovery orientation may support personal recovery

Effects of clinical decision topic on patients’ involvement in and satisfaction with decisions and their subsequent implementation

Clinical decision-making is the vehicle for mental health care delivery, and predictors of decision-making experience and adherence are under-researched. The aim was to investigate the relationship between decision topic and kind of involvement in the decision, satisfaction and subsequent implementation, from both staff and patient perspectives

Impact of cervical screening on cervical cancer mortality: estimation using stage-specific results from a nested case-control study

Cancer Research UK (A16892 to P.S.)