title: Reduced cortical activation in inferior frontal junction in Unverricht-Lundborg disease (EPM1) - A motor fMRI study.
abstract: BACKGROUND
  Unverricht-Lundborg disease (EPM1) is characterized by stimulus-sensitive and action-activated myoclonus, tonic-clonic seizures and ataxia. Several disease-related alterations in cortical structure and excitability have been associated with the motor symptoms of EPM1. This study aimed to elucidate possible alterations in cortical activation related to motor performance in EPM1.
  
  
  METHODS
  Fifteen EPM1-patients and 15 healthy volunteers matched for age and sex underwent motor functional MRI. Group differences in activations were evaluated in the primary and supplementary motor cortices and sensory cortical areas. Furthermore, in EPM1 patients, the quantitative fMRI parameters were correlated with the severity of the motor symptoms.
  
  
  RESULTS
  The EPM1-patients exhibited decreased activation in the left inferior frontal junction (IFJ) during right hand voluntary motor task when compared with controls. In the quantitative analysis, EPM1-patients had significantly weaker activation than controls in the hand knob and supplementary motor areas (SMA). The volume of activation in M1 decreased with age and duration of disease in the patient group, whereas the volume increased with age in controls. Negative correlations were observed between fMRI parameters of SMA and disease duration or age in patients but not in controls.
  
  
  CONCLUSIONS
  The weaker motor fMRI activation observed in EPM1 patients parallels previous neurophysiological findings and correlates with the motor symptoms of the disease. Thus, the observed decrease in IFJ activation in EPM1 patients may be associated with the difficulties in initiation or termination of motor execution, a typical clinical symptom in EPM1. The fMRI findings reflect the progressive nature of this disease.
authors.affiliation: Department of Clinical Radiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland; Department of Clinical Neurophysiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland. Electronic address: mervi.kononen@kuh.fi.
authors.forename: Mervi
authors.initials: M
authors.lastname: Könönen
authors.affiliation: Department of Clinical Neurophysiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland; Department of Clinical Neurophysiology, School of Medicine, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Nils
authors.initials: N
authors.lastname: Danner
authors.affiliation: Department of Clinical Radiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland.
authors.forename: Päivi
authors.initials: P
authors.lastname: Koskenkorva
authors.affiliation: Department of Neurology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland; Department of Neurology, School of Medicine, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Reetta
authors.initials: R
authors.lastname: Kälviäinen
authors.affiliation: Department of Clinical Neurophysiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland.
authors.forename: Jelena
authors.initials: J
authors.lastname: Hyppönen
authors.affiliation: Department of Clinical Neurophysiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland; Department of Clinical Neurophysiology, School of Medicine, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Esa
authors.initials: E
authors.lastname: Mervaala
authors.affiliation: Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Pasi
authors.initials: P
authors.lastname: Karjalainen
authors.affiliation: Department of Clinical Radiology, Kuopio University Hospital, P.O. Box 100, FI-70029 KYS, Finland; Department of Clinical Radiology, Institute of Clinical Medicine, School of Medicine, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Ritva
authors.initials: R
authors.lastname: Vanninen
authors.affiliation: Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Eini
authors.initials: E
authors.lastname: Niskanen
mesh_terms: D000328:Adult; D000367:Age Factors; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D015331:Cohort Studies; D005260:Female; D006225:Hand / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D012720:Severity of Illness Index; D013997:Time Factors; D020194:Unverricht-Lundborg Syndrome / Q000503:physiopathology*; D055815:Young Adult
keywords: EPM1; Functional magnetic resonance imaging; Inferior frontal junction; Motor areas; Unverricht–Lundborg disease; fMRI