title: Impaired comprehension of temporal connectives in Parkinson's disease--a neuroimaging study.
abstract: Parkinson's disease has been found to impair comprehension of complex sentences. Here we follow up on earlier findings that sentences describing two successive events in the form of "Before B, A" are understood worse by Parkinson patients than sentences in the form of "After A, B". Before-initial sentences express events in an order inconsistent with their actual order of occurrence and therefore require additional computations during comprehension. In a behavioral study we tested whether 28 German Parkinson patients reading 'before'- and 'after'-initial sentences correctly understood the sequence of events. A second functional magnetic resonance imaging study investigated 16 different patients who read sentences while in the scanner. The behavioral study revealed that 'before' sentences were misunderstood with regard to the temporal sequence of events in 53% (controls 6.5%). The imaging study demonstrated a functional network of the caudate nucleus, middle frontal gyrus, medial superior frontal gyrus, parietal lobule and inferior temporal gyrus. This network was dynamically modulated for 'before' compared to 'after' sentences in healthy controls but not in Parkinson patients. The current results suggest that the additional computations required for 'before' sentences are supported by a network with the caudate nucleus as a central element. This network was compromised in Parkinson patients. We propose that dysfunction of the caudate nucleus networks underlies Parkinson patients' difficulty in dealing with complex sentence structures.
authors.affiliation: Department of Neurology, University of Lübeck, Lübeck 23538, Germany.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Ye
authors.forename: Maria
authors.initials: M
authors.lastname: Milenkova
authors.forename: Bahram
authors.initials: B
authors.lastname: Mohammadi
authors.forename: Katja
authors.initials: K
authors.lastname: Kollewe
authors.forename: Christoph
authors.initials: C
authors.lastname: Schrader
authors.forename: Reinhard
authors.initials: R
authors.lastname: Dengler
authors.forename: Amir
authors.initials: A
authors.lastname: Samii
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Münte
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D016022:Case-Control Studies; D002421:Caudate Nucleus / Q000503:physiopathology*; D032882:Comprehension; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D059907:Functional Neuroimaging; D006801:Humans; D007802:Language; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000503:physiopathology*; D010300:Parkinson Disease / Q000503:physiopathology*; D013702:Temporal Lobe / Q000503:physiopathology*; D013997:Time Factors