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Major Depressive Disorder (MDD) is common and disabling, and is linked to functional impairment and increased mortality. While current treatments for MDD are moderately effective, ultimately, up to one third of patients do not achieve full remission. Interestingly, while affective symptoms of major depression typically resolve with the depressive episode, cognitive impairment frequently persists, and has been identified as one of the most prominent predictors of illness recurrence. Additionally, MDD is well-recognised as a key risk factor for further cognitive decline and dementia. Yet, available treatments for MDD do not typically address cognitive impairment. Cognitive training, represents a promising and novel therapeutic intervention in this regard. This review systematically identified and evaluated the evidence for cognitive training in adults with MDD. Following PRISMA guidelines, eligible studies were selected according to pre-defined criteria delineating our target population (adults with clinically defined MDD), parameters for cognitive training interventions (computer-or strategy-based, clinician-facilitated), and study design (controlled trials including pre-post cognitive and psychological or functional outcome data). Of 448 studies identified, nine studies met inclusion criteria. These studies were evaluated for methodological quality and risk of bias. Despite heterogeneity, qualitative and meta-analytic synthesis of study findings revealed significant improvements in cognitive and affective outcomes following cognitive training, with moderate pooled effect sizes. Unfortunately, very few studies investigated 'far transfer' to broader domains of everyday functioning. Overall, given the strong evidence for the efficacy and value of cognitive training in this context, cognitive training should be considered as a primary therapeutic intervention in the treatment of MDD.

Background A major gap exists internationally in providing support to maintain functional and social independence of older people with dementia living at home. This project evaluates a model of care that integrates evidence-based strategies into a person-centred interdisciplinary rehabilitation package: Interdisciplinary Home-bAsed Reablement Program (I-HARP). Two central aims are: 1) to determine the effectiveness of I-HARP on functional independence, mobility, quality of life and depression among people with dementia, their home environmental safety, carer burden and quality of life, and I-HARP cost-effectiveness; and 2) to evaluate the processes, outcomes and influencing factors of the I-HARP implementation. Methods I-HARP is a 4-month model of care, integrated in community aged care services and hospital-based community geriatric services, and consists of: 1) 8–12 home visits, tailored to the individual client’s needs, by an occupational therapist, registered nurse, and other allied health staff; 2) minor home modifications/assistive devices to the value of 60 years with mild to moderate dementia and his/her carer). During Phase I, I-HARP advisory group is established and training of I-HARP interventionists is completed, and the effectiveness of I-HARP is examined using a pragmatic RCT. Phase II, conducted concurrently with Phase I, focuses on the process evaluation of the I-HARP implementation using a realist approach. Semi-structured interviews with participants and focus groups with I-HARP interventionists and participating site managers will provide insights into the contexts, mechanisms and outcomes of I-HARP. Discussion I-HARP is being evaluated within the real-world systems of hospital-based and community-based aged care services in Australia. Future directions and strategies for reablement approaches to care for community dwelling people living with dementia, will be developed. The study will provide evidence to inform key stakeholders in their decision making and the use/delivery of the program, as well as influence future systems-thinking and changes for dementia care. Trial registration Australian New Zealand Clinical Trial Registry ACTR N12618000600246 (approved 18/04/2018).

The pathophysiological mechanism of freezing of gait (FoG) has been linked to executive dysfunction. Cognitive training (CT) is a non-pharmacological intervention which has been shown to improve executive functioning in Parkinson’s disease (PD). This study aimed to explore whether targeted CT can reduce the severity of FoG in PD. Patients with PD who self-reported FoG and were free from dementia were randomly allocated to receive either a CT intervention or an active control. Both groups were clinician-facilitated and conducted twice-weekly for seven weeks. The primary outcome was percentage of time spent frozen during a Timed Up and Go task, assessed both on and off dopaminergic medications. Secondary outcomes included multiple neuropsychological and psychosocial measures. A full analysis was first conducted on all participants randomized, followed by a sample of interest including only those who had objective FoG at baseline, and completed the intervention. Sixty-five patients were randomized into the study. The sample of interest included 20 in the CT group and 18 in the active control group. The primary outcome of percentage time spent frozen during a gait task was significantly improved in the CT group compared to active controls in the on-state. There were no differences in the off-state. Patients who received CT also demonstrated improved processing speed and reduced daytime sleepiness compared to those in the active control. The findings suggest that CT can reduce the severity of FoG in the on-state, however replication in a larger sample is required., Freezing of gait: a non-pharmacological approach Cognitive training can reduce the severity of gait freezing in Parkinson’s disease (PD) patients on dopaminergic medication. The inability to move forwards despite the intention to walk is one of the most debilitating symptoms in patients with PD and has been linked to cognitive dysfunction. Simon Lewis at the University of Sydney, Australia, and colleagues examined the effects of cognitive training in patients with self-reported freezing of gait and without dementia. Patients receiving cognitive therapy twice a week for seven weeks showed a significant reduction in gait freezing compared to the control group. Interestingly, the effect was observed when patients had maximum benefit from their PD medication (on-state) but not in the off-state. Cognitive training also improved patients’ processing speed and reduced their daytime sleepiness highlighting the usefulness of non-pharmacological interventions in the treatment of PD.

Freezing of gait is a frequent and disabling symptom experienced by many patients with Parkinson's disease. A number of executive deficits have been shown to be associated with the phenomenon suggesting a common underlying pathophysiology, which as of yet remains unclear. Neuroimaging studies have also implicated the role of the cognitive control network in patients with freezing. To explore this concept, the current study examined error-monitoring as a measure of cognitive control. Thirty-four patients with and 38 without freezing of gait, who were otherwise well matched on disease severity, completed a colour-word interference task that allowed the specific assessment of error monitoring during conflict. Whilst both groups performed colour-naming and word-reading tasks equally well, those patients with freezing showed a pattern between conditions whereby they were better able to monitor performance and self-correct errors in the pure inhibition task but not after a switching rule was introduced. The novel results shown here provide insight into possible pathophysiological mechanisms involved in cognitive load and error monitoring in patients with freezing of gait. These results provide further evidence for the role of functional frontostriatal circuitry impairments in patients with freezing of gait and have implications for future studies and possible therapeutic interventions.

The concept of differing clinical phenotypes within Parkinson’s disease (PD) is well represented in the literature. However, there is no consensus as to whether any particular disease phenotype is associated with an increased risk of mild cognitive impairment (MCI) using the newly proposed Movement Disorders Society diagnostic criteria for this feature. To explore the expression of PD-MCI in relation to the heterogeneity of idiopathic PD. A cluster analysis incorporating a range of specific demographic, clinical and cognitive variables was performed on 209 patients in the early stages of PD (between Hoehn and Yahr stages I–III). Post hoc analyses exploring variables not included in the clustering solution were performed to interrogate the veracity of the subgroups generated. This study identified four distinct PD cohorts: a younger disease-onset subgroup, a tremor dominant subgroup, a non-tremor dominant subgroup, and a subgroup with rapid disease progression. The present study identified a differential expression of PD-MCI across these subgroups, with the highest frequency observed in the non-tremor dominant cluster. The non-tremor dominant subgroup was also associated with a higher prevalence of freezing of gait, hallucinations, daytime somnolence, and rapid eye movement sleep behavior disorder compared with other subgroups. This study confirms the existence of heterogeneity within the early clinical stages of PD and for the first time highlights the differential expression of PD-MCI using the newly defined diagnostic criteria for this feature. An improved understanding of PD-MCI and its clinical relationships may lead to an improved understanding of the pathophysiology underlying heterogeneity in PD. A subset of patients with Parkinson’s disease (PD) shows a higher frequency of mild cognitive impairment (MCI). Disease pathways underlying cognitive symptoms of PD are not well understood, making it difficult to determine which patients are at highest risk. Researchers in Australia led by Simon Lewis at the University of Sydney analyzed cognitive and other variables in 209 patients with early stage PD, using new diagnostic criteria proposed by the International Parkinson and Movement Disorder Society. The team confirmed that patients could be divided into four groups: younger onset, tremor dominant, non-tremor dominant (NTD), and rapid disease progression. The NTD subgroup showed the highest frequency of MCI (54%), combined with a higher prevalence of other symptoms. Improving understanding of MCI in PD may therefore help to identify patients who would benefit from dementia intervention strategies.