title: Dysfunctional and compensatory duality in mild cognitive impairment during a continuous recognition memory task.
abstract: One of the current issues of debate in the study of mild cognitive impairment (MCI) is deviations of oscillatory brain responses from normal brain states and its dynamics. This work aims to characterize the differences of power in brain oscillations during the execution of a recognition memory task in MCI subjects in comparison with elderly controls. Magnetoencephalographic (MEG) signals were recorded during a continuous recognition memory task performance. Oscillatory brain activity during the recognition phase of the task was analyzed by wavelet transform in the source space by means of minimum norm algorithm. Both groups obtained a 77% hit ratio. In comparison with healthy controls, MCI subjects showed increased theta (p<0.001), lower beta reduction (p<0.001) and decreased alpha and gamma power (p<0.002 and p<0.001 respectively) in frontal, temporal and parietal areas during early and late latencies. Our results point towards a dual pattern of activity (increase and decrease) which is indicative of MCI and specific to certain time windows, frequency bands and brain regions. These results could represent two neurophysiological sides of MCI. Characterizing these opposing processes may contribute to the understanding of the disorder.
authors.affiliation: Laboratory of Cognitive and Computational Neuroscience, Centre for Biomedical Technology, Technical University of Madrid and Complutense University of Madrid, Madrid, Spain. sara.aurtenetxe@ctb.upm.es
authors.forename: Sara
authors.initials: S
authors.lastname: Aurtenetxe
authors.forename: Nazareth P
authors.initials: NP
authors.lastname: Castellanos
authors.forename: Stephan
authors.initials: S
authors.lastname: Moratti
authors.forename: Ricardo
authors.initials: R
authors.lastname: Bajo
authors.forename: Pedro
authors.initials: P
authors.lastname: Gil
authors.forename: Garikoitz
authors.initials: G
authors.lastname: Beitia
authors.forename: Francisco
authors.initials: F
authors.lastname: del-Pozo
authors.forename: Fernando
authors.initials: F
authors.lastname: Maestú
mesh_terms: D000368:Aged; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D021641:Recognition, Psychology / Q000502:physiology*