Lars Hyllienmark's research group
Electrophysiological techniques still have an important role in the detection of functional brain impairment. These methods can monitor rapid brain signals better than any other technique.
The aim has been to develop EEG methodology by using advanced signal analysis technology, and by the systematic processing of data on normal variability and data obtained under experimental conditions. The research group is now applying this technique to demonstrate how different diseases, mainly diabetes and multiple sclerosis, affect brain electrical activity and how this is related to changes in cognitive function, e.g. memory, attention and mental agility.
It is well known that diabetes causes damage to the nervous system, blood vessels and kidneys, and it is increasingly being recognised that some impairment of cognitive function may also occur as a consequence of diabetes. This applies both to patients with juvenile (type 1) and age-related (type 2) diabetes. Different theories have been put forward to explain this. We have carried out a large study of adult patients with type 1 diabetes, and this shows a clear association between changes in brain signals and impaired cognitive function. The greatest impairment is seen in psychomotor agility, and this correlates strongly to the amplitude of the response to auditory stimuli. The mechanism behind these signal changes may be damage to the white matter (myelin), which affects the synchronisation of impulse conduction in the brain. The most obvious clinical association with these changes was long-term diabetes, which can result in disturbances of the growth-promoting effects of insulin on brain cells. We are currently studying the effect of insulin treatment on brain signals and cognitive function in patients with type 2 diabetes.
With regard to MS, the main aim of our research is to detect the early effects of the disease, and those that are not directly associated with obvious volume changes or damaged white matter, as shown by MR imaging. We are studying how changes induced in resting brain activity by visual and auditory stimulation relates to cognitive function and to other disease factors.
- Ion mechanisms in nerves
- The functional organisation of the brain, functional magneticresonancetomography
- Mechanisms underlying peripheral nerve damage (diabetes and MS)
A novel NGFB point mutation: a phenotype study of heterozygous patients.
Minde J, Andersson T, Fulford M, Aguirre M, Nennesmo I, Remahl I, et al
J. Neurol. Neurosurg. Psychiatry 2009 Feb;80(2):188-95
Cognitive impairment has a strong relation to nonsomatic symptoms of depression in relapsing-remitting multiple sclerosis.
Sundgren M, Maurex L, Wahlin, Piehl F, Brismar T
Arch Clin Neuropsychol 2013 Mar;28(2):144-55