Understanding Mental Fatigue After Stroke

Mental fatigue is a major problem for stroke survivors and sometimes remains present years after the event. It is often rated as the most persisting and frustrating symptom. For many, mental fatigue has a significant negative effect on rehabilitation, and patients report difficulties with returning to previous levels of participation in their meaningful everyday activities whether at home, work or in the community.

The development of effective evidence based interventions have been limited by our understanding of post stroke fatigue. This may be attributed to the fact that the underlying mechanisms for post stroke mental fatigue are unknown. Evolving theories suggest that mental fatigue may be associated with a dysfunction in the cognitive domain of attention.

An impairment in the domain of attention may result in previously effortless activities of daily living that require sustained attention to become exhausting. Specific knowledge on the influence of background noise and other distractions on a person's ability to sustain attention after stroke is lacking. This research project will contribute to new and important knowledge in this area.

A total of 30 adults will be reviewed at least 2 months after stroke on tasks that require sustained attention. The investigators plan to observe the influence background distraction has on the ability to do these tasks and whether wearing earphones will assist with concentration levels, and reduce fatiguing situations.

This project provides a unique opportunity to investigate how a dysfunction in the cognitive domain of attention may be related to the experience of mental fatigue after stroke. The investigators will use a reaction time based test, fatigue questionnaires, alongside the wearing of earphones when examining associations. This knowledge may help to determine who is at risk of developing symptoms of mental fatigue. Furthermore, it may shed a light on possible prevention strategies, and provide more suitable guidance to those affected by mental fatigue.

Fatigue is reported by stroke survivors as a highly problematic and persisting experience with many rating it as their most severe amongst all post - stroke sequelae. Given the negative impact of fatigue on participation, an investigation into the possible underlying mechanisms mediating fatigue after stroke has clinical implications.

Recent studies indicate that an impairment in the domain of attention is related to the experience of higher fatigue levels. However, the complexity of this mechanism, presentation and measurement have made the findings unclear. In studies, testing methods to identify a dysfunction in the domain of attention can be mentally fatiguing. Moreover, it is not clear whether the impact of contextual factors on concentration levels, such as background noise and distraction, has been considered.

Primary Objective:

Among people with stroke engaging in a task requiring sustained attention, to what extent does the use of noise-cancelling earphones impact on mental fatigue? Fatigue will be assessed using two measures: 1) The Continuous Performance Test, a reaction time based assessment completed on a computer tablet and 2) A Visual Analog Scale for Fatigue, which is paper based.

Design: A cross - over repeated exposure randomised design will be used. Study participants will be randomised to do tasks of sustained attention, followed by a reaction time based assessment on a tablet, first with and then without earphones or first without and then with earphones. The two assessment sessions will be done one week apart to allow for a washout period. Participants will be invited to rank their fatigue levels on a visual analog scale, pre - post these assessments.

Secondary Objectives:

* Is baseline cognitive fatigue a predictor for performance decrement on tasks of sustained attention? This will be assessed using the Fatigue Scale for Motor and Cognitive Functions (FSMC). This scale includes both physical and cognitive aspects of fatigue.
* What are the contextual factors mediating fatigue symptoms? This will be assessed using a momentary ecological assessment application on a mobile phone or a diary paper based assessment.
* What is the influence of fatigue symptoms on participatory patterns as seen on the ecological momentary app or diary? This will be assessed with a wrist worn Accelerometer.

Eligibility Criteria:
Inclusion Criteria:

* Clinical diagnosis of stroke
* Are over the age of 18 (no upper limit)
* Ability to understand spoken and / or written English

Exclusion Criteria:

* Not functionally able to undergo neuropsychological assessment or reply to questionnaires. This will be assessed on the cognitive screen, the Oxford Cognitive Screen (OCS).
* Medically unstable or have another condition that could impact results (e.g. substance abuse).