Brain Rhythms in Altered Vision After Stroke Part 2 (BRAVAS-2)
Research type
Research Study
Full title
Brain Rhythms in Altered Vision After Stroke Part 2 (BRAVAS-2)
IRAS ID
247535
Contact name
Gemma Learmonth
Contact email
Sponsor organisation
NHS Greater Glasgow & Clyde
Duration of Study in the UK
2 years, 6 months, 21 days
Research summary
Research Summary
Some patients can be affected by a condition called “hemispatial neglect” (or “neglect”) after a stroke. Patients with neglect often behave as though one side of their environment (usually the left) no longer exists. This is caused by a disruption of the areas of the brain that are responsible for attention, but the areas responsible for vision are usually not affected. Unfortunately, patients with neglect often do not recover as well or as quickly as patients without neglect, and there are very few treatments available with which to improve this problem.
Our main goal is to see whether we can find specific markers of impaired attention (neglect) and impaired vision (a condition called “hemianopia) using a procedure called electroencephalography (EEG). Secondly, we will assess whether it is possible to record good-quality EEGs in a larger sample of patients with these conditions. During EEG recording, we will investigate the effects of stimulation using a short sound (called “phasic alerting”) that may improve the patient’s ability to see a small square (“target”) on a computer screen. It is thought that the sound may improve general alertness, which in turn might improve attention because of the strong connections between these areas in the brain.
We hope to answer the following questions: does phasic alerting benefit patients with neglect more than patients with hemianopia; and are there are differences in the response between right and left sided strokes.
Summary of Results
Some patients can be affected by a condition called “hemispatial neglect” (or “neglect”) after a stroke. Patients with neglect often behave as though one side of their environment (usually the left) no longer exists. This is caused by a disruption of the areas of the brain that are responsible for attention, but the areas responsible for vision are usually not affected. Unfortunately, patients with neglect often do not recover as well or as quickly as patients without neglect, and there are very few treatments available with which to improve this problem.
Our main goal was to see whether we can find specific markers of impaired attention (neglect) and impaired vision (a condition called “hemianopia”) using a procedure called electroencephalography (EEG). Secondly, we wanted to know whether it was possible to record good-quality EEGs in a larger sample of patients with these conditions.
During EEG recording, we investigated the effects of stimulation using a short sound (called “phasic alerting”) that was hoped to improve the patient’s ability to see a small square (“target”) on a computer screen. It was hoped that the sound may improve general alertness, which in turn might improve attention because of the strong connections between these areas in the brain.
We recruited a total of 16 people after stroke. Unfortunately, we found that the sound did not improve their ability to see the squares that were presented to their affected side. We found that generally, the brain rhythms that are linked to visual attention in areas of the brain that were affected by stroke were similar to people who had not had a stroke. We are still working to understand why these brain rhythms are preserved and how they are related to difficulties with vision and attention.
REC name
West of Scotland REC 4
REC reference
18/WS/0094
Date of REC Opinion
11 Jul 2018
REC opinion
Further Information Favourable Opinion