Imaging the effects of cognitive rehabilitation interventions: developing paradigms for the assessment and rehabilitation of prospective memory

Prospective memory (PM), the ability to remember to carry out future intentions and goals following a delay filled with other unrelated tasks is often compromised following brain injury and other psychological and psychiatric disorders affecting the frontal lobes. It has long been acknowledged that patients with frontal lobe lesions can show relatively intact performance in laboratory settings yet their everyday functioning in multitasking situations requiring PM may be severely impaired (Mesulam 1986). The last 15 years has seen a marked expansion into research and theoretical models of prospective memory and its neural basis with the findings from recent neuroimaging studies suggesting that Brodmann’s area 10 plays an important role in PM (Burgess et al., 2011). The aim of this thesis was to develop paradigms for assessing prospective memory that could be used to measure the behavioural and functional changes in the brain following brief cognitive rehabilitation interventions with the first part of the thesis (Chapters 2-4) investigating the convergent and ecological validity of computerised assessment measures of PM in a group of young and older neurologically healthy individuals, as well as in individuals with acquired brain injury. The second part of the thesis (Chapters 5 and 6) investigated the behavioural and neural changes associated with a brief PM intervention developed from the principles of Goal Management Training (Robertson 1996; Levine et al., 2000; 2012) and Implementation Intentions (Gollwitzer 1993; 1996). Chapter 1 provides a brief overview of the assessment and rehabilitation of PM. Chapter 2 assessed age related changes in performance on the computerised PM tests and a modified version of the Hotel Test (Manly et al., 2002) in a group of young and older neurologically healthy individuals. Both the computerised tasks and the modified Hotel Test (mHT) were found to be sensitive to the effects of ageing. Chapter 3 investigated the effects of a brief break filled with an unrelated task on performance on computerised PM tasks. A brief break was found to have a negative effect on performance with the amount of performance decay correlating with self-reported memory functioning. Chapter 4 assessed the convergent and ecological validity of the computerised PM tasks and their sensitivity to brain injury. The tasks were found to have good convergent validity with the mHT and the CAMPROMPT. The informant- and self-ratings of everyday memory and goal management functioning correlated with task performance in the ABI sample. Chapter 5 investigated whether brief intervention aimed at reducing PM lapses would be successful in improving performance on computerised PM task compared with a control training intervention. Chapter 6 investigated the functional changes in brain activation associated with this brief training. Significant behavioural improvements on the computerised PM tasks were seen following brief training with some evidence of transfer of the effect to a novel task. Significant changes in neural activations within Brodmann’s area 10 were seen following brief training in the trained group compared to the control group. The findings have implications for the assessment and rehabilitation of individuals with PM problems and are discussed in relation to cognitive theories of PM

The effectiveness of the behavioural components of cognitive behavioural therapy for insomnia in older adults:A systematic review

Insomnia is more prevalent in older adults (< 60 years) than in the general population. Cognitive behavioural therapy for insomnia is the gold-standard treatment; however, it may prove too cognitively taxing for some. This systematic review aimed to critically examine the literature exploring the effectiveness of explicitly behavioural interventions for insomnia in older adults, with secondary aims of investigating their effect on mood and daytime functioning. Four electronic databases (MEDLINE – Ovid, Embase – Ovid, CINAHL, and PsycINFO) were searched. All experimental, quasi-experimental and pre-experimental studies were included, provided they: (a) were published in English; (b) recruited older adults with insomnia; (c) used sleep restriction and/or stimulus control; (d) reported outcomes pre-and-post intervention. Database searches returned 1689 articles; 15 studies, summarising the results of 498 older adults, were included – three focused on stimulus control, four on sleep restriction, and eight adopted multicomponent treatments comprised of both interventions. All interventions brought about significant improvements in one or more subjectively measured facets of sleep although, overall, multicomponent therapies demonstrated larger effects (median Hedge's g = 0.55). Actigraphic or polysomnographic outcomes demonstrated smaller or no effects. Improvements in measures of depression were seen in multicomponent interventions, but no intervention demonstrated any statistically significant improvement in measures of anxiety. This corroborates with the existing consensus that multicomponent approaches confer the most benefit, and adds to the literature by demonstrating this to be the case in brief, explicitly behavioural interventions. This review guides future study of treatments for insomnia in populations where cognitive behavioural therapy for insomnia is not appropriate

Assessing insomnia after stroke: a diagnostic validation of the Sleep Condition Indicator in self-reported stroke survivors

Background: Insomnia is common after stroke and is associated with poorer recovery and greater risk of subsequent strokes. Yet, no insomnia measures have been validated in English-speaking individuals affected by stroke. Aims: This prospective diagnostic validation study investigated the discriminatory validity and optimal diagnostic cut-off of the Sleep Condition Indicator when screening for Diagnostic and Statistical Manual of Mental Disorders—fifth edition (DSM-5) insomnia disorder post-stroke. Methods: A convenience sample of 180 (60.0% women, mean age=49.61 ± 12.41 years) community-based, adult (≥18 years) self-reported stroke survivors completed an online questionnaire. Diagnosis of DSM-5 insomnia disorder was based on analysis of a detailed sleep history questionnaire. Statistical analyses explored discriminant validity, convergent validity, relationships with demographic and mood variables, and internal consistency. Receiver operating characteristic curves were plotted to assess diagnostic accuracy. Results: Data from the sleep history questionnaire suggested that 75 participants (41.67%) met criteria for DSM-5 insomnia disorder, 33 (18.33%) exhibited symptoms of insomnia but did not meet diagnostic criteria, and 72 (40.0%) had no insomnia symptoms at the time of assessment. The Sleep Condition Indicator (SCI) demonstrated ‘excellent’ diagnostic accuracy in the detection of insomnia post-stroke, with an area under the curve of 0.86 (95% CI (0.81, 0.91)). The optimal cut-off was determined as being ≤13, yielding a sensitivity of 88.0% and a specificity of 71.43%. Conclusions: The findings of this study demonstrate the SCI to be a valid and reliable method with which to diagnose DSM-5 insomnia disorder and symptoms post-stroke. However, a lower threshold than is used in the general population may be necessary after stroke

Incidence and prevalence of post-stroke insomnia: a systematic review and meta-analysis

Problems with sleep are reported to be common after stroke but the incidence and prevalence of insomnia and insomnia symptoms following stroke is not yet established. The aim of this review was to conduct a systematic review and meta-analysis of the incidence and prevalence of insomnia and insomnia symptoms in individuals affected by stroke. We searched seven main electronic databases to identify studies until September 25, 2018. No studies examining incidence of post-stroke insomnia were identified. Twenty-two studies on prevalence of insomnia or insomnia symptoms including individuals with stroke were included with fourteen studies suitable for inclusion in the meta-analysis. Meta-analysis indicated pooled prevalence of 38.2% (CI 30.1–46.5) with significantly higher prevalence estimates for studies using non-diagnostic tools, 40.70% (CI 30.96–50.82) compared to studies using diagnostic assessment tools 32.21% (CI 18.5–47.64). Greater insomnia symptoms were indicated in those with comorbid depression and anxiety. The prevalence of both insomnia and insomnia symptoms are considerably higher in stroke survivors compared to the general population. Studies investigating the incidence, insomnia symptom profile and changes in insomnia prevalence over time are needed to inform clinical practice and to encourage tailored interventions that consider this symptomatology. PROSPERO registration number CRD42017065670

Measuring the effects of listening for leisure on outcome after stroke (MELLO):A pilot randomized controlled trial of mindful music listening

Background: Cognitive deficits and low mood are common post-stroke. Music listening is suggested to have beneficial effects on cognition, while mindfulness may improve mood. Combining these approaches may enhance cognitive recovery and improve mood early post-stroke. Aims: To assess the feasibility and acceptability of a novel mindful music listening intervention. Methods: A parallel group randomized controlled feasibility trial with ischemic stroke patients, comparing three groups; mindful music listening, music listening and audiobook listening (control group), eight weeks intervention. Feasibility was measured using adherence to protocol and questionnaires. Cognition (including measures of verbal memory and attention) and mood (Hospital Anxiety and Depression Scale) were assessed at baseline, end of intervention and at six-months post-stroke. Results: Seventy-two participants were randomized to mindful music listening (n = 23), music listening (n = 24), or audiobook listening (n = 25). Feasibility and acceptability measures were encouraging: 94% fully consistent with protocol; 68.1% completing ≥6/8 treatment visits; 80–107% listening adherence; 83% retention to six-month endpoint. Treatment effect sizes for cognition at six month follow-up ranged from d = 0.00 ([−0.64,0.64], music alone), d = 0.31, ([0.36,0.97], mindful music) for list learning; to d = 0.58 ([0.06,1.11], music alone), d = 0.51 ([−0.07,1.09], mindful music) for immediate story recall; and d = 0.67 ([0.12,1.22], music alone), d = 0.77 ([0.16,1.38]mindful music) for attentional switching compared to audiobooks. No signal of change was seen for mood. A definitive study would require 306 participants to detect a clinically substantial difference in improvement (z-score difference = 0.66, p = 0.017, 80% power) in verbal memory (delayed story recall). Conclusions: Mindful music listening is feasible and acceptable post-stroke. Music listening interventions appear to be a promising approach to improving recovery from stroke

The sensitivity and specificity of the Sleep Condition Indicator when screening for insomnia post-stroke: A diagnostic validation

Background: Post-stroke insomnia is common and associated with poorer outcomes and greater risk of recurrent stroke. Highlighting the importance of identifying individuals who require targeted sleep interventions. However, validations of existing insomnia screening tools in English are lacking. Aims: This prospective diagnostic tool validation investigated the discriminatory validity and optimal diagnostic cut-off of the Sleep Condition Indicator (SCI), and a shorter 2-item version (SCI-2) when screening for DSM-V insomnia disorder post-stroke. Methods: A convenience sample of 180 (60.0% female) UK community based, adult (≥18) stroke survivors completed an online questionnaire. Exclusion criteria included: being jetlagged, working nightshifts, and undergoing treatment that may interfere with sleep. The accuracy of the SCI, and a shorter 2-item version (SCI-2), were validated against diagnoses made via a comprehensive sleep history questionnaire. Statistical analyses explored the discriminant validity, convergent validity, and internal consistency. Receiver operating characteristic curves were plotted to assess the diagnostic accuracy of the SCI and SCI-2. General demographic information was also compared between classifications. The pre-registered protocol for this study can be found at: https://doi.org/10.17605/OSF.IO/4DGXW. Results: The mean age of participants was 49.61 years (SD = 12.41, range = 20 - 79). Seventy-five (41.67%) met criteria for DSM-V insomnia disorder, 33 (18.33%) exhibited symptoms of insomnia but did not meet diagnostic criteria, and 72 (40.0%) had no insomnia symptoms. When detecting DSM-V insomnia post-stroke, the SCI demonstrated ‘excellent’ diagnostic accuracy with an AUC of 0.86 (95% CI [0.81, 0.91]). The optimal cut off was ≤13, yielding a sensitivity of 88.0%, a specificity of 71.43%. A robust, negative relationship existed between the SCI and the ISI (r = -0.86, p<.001). The SCI demonstrated ‘good’ internal consistency, with a Cronbach’s α of 0.84 (95% CI [0.80, 0.87]). Conclusions: This study confirms the SCI’s validity and reliability when detecting DSM-V insomnia in English speaking stroke survivors. The SCI demonstrates ‘excellent’ diagnostic accuracy post-stroke; however, lower thresholds may be necessary compared to the general population. The scale’s accuracy, reliability, and brevity, make it an attractive and cost-effective means of screening for DSM-V insomnia disorder post-stroke, in both clinical and research settings

Positive PsychoTherapy in ABI Rehab (PoPsTAR):A pilot randomised controlled trial

Psychological distress is common following acquired brain injury (ABI), but the evidence base for psychotherapeutic interventions is small and equivocal. Positive psychotherapy aims to foster well-being by increasing experiences of pleasure, engagement and meaning. In this pilot trial, we investigated the feasibility and acceptability of brief positive psychotherapy in adults with ABI and emotional distress. Participants were randomised to brief positive psychotherapy plus usual treatment, or usual treatment only. Brief positive psychotherapy was delivered over eight individual out-patient sessions, by one research psychologist. A blinded assessor administered the Depression Anxiety Stress Scales (DASS-21) and the Authentic Happiness Inventory (AHI) at 5, 9 and 20 weeks post-baseline. Of 27 participants randomised (median age 57; 63% male; 82% ischaemic stroke survivors; median 5.7 months post-injury), 14 were assigned to positive psychotherapy, of whom 8 completed treatment. The intervention was feasible to deliver with excellent fidelity, and was acceptable to participants. Retention at 20 weeks was 63% overall. A full-scale trial would need to retain n = 39 per group to end-point, to detect a significant difference in change scores on the DASS-21 Depression scale of 7 points (two-tailed alpha = .05, power = .80). Trials including an active control arm would require larger sample sizes. We conclude that a full-scale trial to investigate efficacy is warranted