Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Int J Psychophysiol. 2003 Aug;49(2):147-63.

Memory-related EEG power and coherence reductions in mild Alzheimer's disease.

Author information

  • 1Mercer's Institute for Research on Ageing, St. James's Hospital, Dublin, Ireland. michael.hogan@nuigalway.ie

Abstract

OBJECTIVES:

To examine memory-related EEG power and coherence over temporal and central recording sites in patients with early Alzheimer's disease (AD) and normal controls.

METHOD:

EEG was recorded from central (Fz, Cz and Pz) and temporal (T3 and T4) electrodes while ten very mild AD patients and ten controls performed a Sternberg-type memory scanning task with three levels of working memory load. Spectral power in delta (0-3 Hz), theta (3-5 Hz), lower alpha1 (5-7 Hz), lower alpha2 (7-9 Hz), upper alpha (9-11 Hz) and beta (15-30 Hz) was averaged for temporal and central electrodes. Coherence was averaged between central electrodes, between central and right temporal electrodes and between central and left temporal electrodes.

RESULTS:

While behavioral performance of very mild AD patients did not differ significantly from that of normal controls, findings suggest that normal controls but not AD patients respond to memory demands by increasing upper alpha power over temporal cortex. When compared with normal controls, AD patients had reduced upper alpha coherence between central and right temporal cortex.

DISCUSSION:

Results are consistent with previous research on the role of upper alpha in semantic memory and suggest that very mild AD may inhibit selective synchronization of upper alpha in temporal lobes. Reduced coherence between central and temporal cortex is discussed in light of a neurological model of AD that hypothesizes reduced electrocortical efficiency and a breakdown of neural network communication to temporal lobes possibly resulting from temporal lobe atrophy.

PMID:
12919717
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk