Event-related potentials elicited during working memory are altered in mild cognitive impairment.
Persons with Mild Cognitive Impairment (MCI) can experience deficits in working memory. In the present study, we investigated working memory in persons with MCI and cognitively healthy older adults using event-related potentials (ERPs). Participants performed an n-back working memory task with baseline (0-back), low load (1-back), and high load (2-back) working memory conditions. MCI participants' performance was less accurate than that of healthy older adults in both the 1-back and 2-back conditions, and reaction times were longer in MCI than control participants in the 0-back, 1-back and 2-back conditions. ERP analyses revealed delayed P200 and N200 latencies and smaller P300 amplitudes in MCI relative to control participants in the 0-back, 1-back and 2-back conditions. Deterioration in working memory performance concomitant with marked electrophysiological alterations suggests that persons with MCI exhibit deficits in several cognitive processes that include early attention, stimulus discrimination and classification, and updating and manipulation of information held in working memory.
University of Ottawa, School of Psychology, Vanier Hall, 136 Jean Jacques Lussier, Ottawa, ON K1N 6N5, Canada; Bruyère Research Institute, 75 Bruyère St., Ottawa, ON K1N 5C8, Canada.
Rocío A
RA
López Zunini
Bruyère Research Institute, 75 Bruyère St., Ottawa, ON K1N 5C8, Canada; Bruyère Memory Program, Bruyère Continuing Care, 43 Bruyère St, Ottawa, ON K1N 5C8, Canada; Carleton University, Faculty of Engineering and Design, 3010 The Minto Centre, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada; University of Ottawa, Faculty of Medicine, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada.
Frank
F
Knoefel
Bruyère Research Institute, 75 Bruyère St., Ottawa, ON K1N 5C8, Canada.
Courtney
C
Lord
University of Ottawa, School of Psychology, Vanier Hall, 136 Jean Jacques Lussier, Ottawa, ON K1N 6N5, Canada.
Fiatsogbe
F
Dzuali
Bruyère Memory Program, Bruyère Continuing Care, 43 Bruyère St, Ottawa, ON K1N 5C8, Canada.
Michael
M
Breau
Bruyère Research Institute, 75 Bruyère St., Ottawa, ON K1N 5C8, Canada; Bruyère Memory Program, Bruyère Continuing Care, 43 Bruyère St, Ottawa, ON K1N 5C8, Canada.
Lisa
L
Sweet
Bruyère Research Institute, 75 Bruyère St., Ottawa, ON K1N 5C8, Canada; Bruyère Memory Program, Bruyère Continuing Care, 43 Bruyère St, Ottawa, ON K1N 5C8, Canada; Carleton University, Faculty of Engineering and Design, 3010 The Minto Centre, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
Rafik
R
Goubran
University of Ottawa, School of Psychology, Vanier Hall, 136 Jean Jacques Lussier, Ottawa, ON K1N 6N5, Canada; Bruyère Research Institute, 75 Bruyère St., Ottawa, ON K1N 5C8, Canada. Electronic address: vtaler@uottawa.ca.
Vanessa
V
Taler
D000368:Aged; D000647:Amnesia / Q000503:physiopathology; D060825:Cognitive Dysfunction / Q000503:physiopathology*; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*
Event-related potentials; Mild cognitive impairment; N-back; Working memory