Myelin is the protective coating surrounding nerve fibres of the brain and spinal cord and it is this coating that is lost in MS. The cells that produce myelin are called oligodendrocytes. The loss of these myelin producing cells is linked to the increasing disability and cognitive dysfunction (thinking and memory problems, often called ‘brain fog’) that people with MS can experience over time. While often overshadowed by other symptoms, over half of people with MS report thinking and memory problems as symptoms.
Recent evidence has shown that learning a complex repetitive physical movement increases the number of oligodendrocytes in the brain. This has led to the hypothesis that other tasks may also affect the numbers of these types of cells.
With the help of this Incubator Grant, Dr Cullen will use a laboratory model to test if performing memory tasks increases oligodendrocytes in the brain. She will then determine if increasing the numbers of these cells increases the production of myelin around nerve cells in the brain.
The results from this study may be used to develop an effective cognitive training program for people with MS which may help relieve ‘brain fog’ and promote MS lesion repair.
Dr Cullen showed that by learning a task that related to working memory, reference memory, procedural memory and spatial navigation, the laboratory models increased the number of new myelin producing cells in the brain. In addition, in response to the learning task, the mature myelin producing cells were able to increase the length travelled by electrical signals along the nerve fibre – meaning that this type of learning could also boost beneficial changes in the existing myelin producing cells in the brain.
Dr Cullen is currently investigating whether the learning task can assist in promoting lesion repair in laboratory models of MS. She has established a model for demyelination to perform the series of experiments necessary to address this with experiments for this ongoing.
This work has been presented at an international conference in the US and has led to several international collaborations.
Updated: 11 June 2020
Updated: 02 January, 2018