Matthias Grieder1, Thomas Koenig2, Toshihiko Kinoshita3, Keita Utsunomiya4, Lars-Olof Wahlund5, Thomas Dierks2, Keiichiro Nishida3. 1. Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland. Electronic address: grieder@puk.unibe.ch. 2. Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland. 3. Department of Neuropsychiatry, Kansai Medical University, Osaka, Japan. 4. Department of Radiology, Kansai Medical University, Osaka, Japan. 5. Karolinska Institute, Dept. NVS, Division of Clinical Geriatrics, Stockholm, Sweden.
Abstract
OBJECTIVE: Diagnosis of semantic dementia relies on cost-intensive MRI or PET, although resting EEG markers of other dementias have been reported. Yet the view still holds that resting EEG in patients with semantic dementia is normal. However, studies using increasingly sophisticated EEG analysis methods have demonstrated that slightest alterations of functional brain states can be detected. METHODS: We analyzed the common four resting EEG microstates (A, B, C, and D) of 8 patients with semantic dementia in comparison with 8 healthy controls and 8 patients with Alzheimer's disease. RESULTS: Topographical differences between the groups were found in microstate classes B and C, while microstate classes A and D were comparable. The data showed that the semantic dementia group had a peculiar microstate E, but the commonly found microstate C was lacking. Furthermore, the presence of microstate E was significantly correlated with lower MMSE and language scores. CONCLUSION: Alterations in resting EEG can be found in semantic dementia. Topographical shifts in microstate C might be related to semantic memory deficits. SIGNIFICANCE: This is the first study that discovered resting state EEG abnormality in semantic dementia. The notion that resting EEG in this dementia subtype is normal has to be revised.
OBJECTIVE: Diagnosis of semantic dementia relies on cost-intensive MRI or PET, although resting EEG markers of other dementias have been reported. Yet the view still holds that resting EEG in patients with semantic dementia is normal. However, studies using increasingly sophisticated EEG analysis methods have demonstrated that slightest alterations of functional brain states can be detected. METHODS: We analyzed the common four resting EEG microstates (A, B, C, and D) of 8 patients with semantic dementia in comparison with 8 healthy controls and 8 patients with Alzheimer's disease. RESULTS: Topographical differences between the groups were found in microstate classes B and C, while microstate classes A and D were comparable. The data showed that the semantic dementia group had a peculiar microstate E, but the commonly found microstate C was lacking. Furthermore, the presence of microstate E was significantly correlated with lower MMSE and language scores. CONCLUSION: Alterations in resting EEG can be found in semantic dementia. Topographical shifts in microstate C might be related to semantic memory deficits. SIGNIFICANCE: This is the first study that discovered resting state EEG abnormality in semantic dementia. The notion that resting EEG in this dementia subtype is normal has to be revised.
Authors: Anna Custo; Dimitri Van De Ville; William M Wells; Miralena I Tomescu; Denis Brunet; Christoph M Michel Journal: Brain Connect Date: 2017-11-17
Authors: Julia Schumacher; Luis R Peraza; Michael Firbank; Alan J Thomas; Marcus Kaiser; Peter Gallagher; John T O'Brien; Andrew M Blamire; John-Paul Taylor Journal: Brain Date: 2019-06-01 Impact factor: 13.501