Original Research ARTICLE
Recognition memory in amnestic-mild cognitive impairment: insights from event-related potentials
- 1Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
- 2Penn Memory Center, University of Pennsylvania, Philadelphia, PA, USA
- 3Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, USA
Episodic memory loss is the hallmark cognitive dysfunction associated with Alzheimer’s disease (AD). Amnestic mild cognitive impairment (a-MCI) frequently represents a transitional stage between normal aging and early AD. A better understanding of the qualitative features of memory loss in a-MCI may have important implications for predicting those most likely to harbor AD-related pathology and for disease monitoring. Dual process models of memory argue that recognition memory is subserved by the dissociable processes of recollection and familiarity. Work studying recognition memory in a-MCI from this perspective has been controversial, particularly with regard to the integrity of familiarity. Event-related potentials (ERPs) offer an alternative means for assessing these functions without the associated assumptions of behavioral estimation methods. ERPs were recorded while a-MCI patients and cognitively normal (CN) age-matched adults performed a recognition memory task. When retrieval success was measured (hits versus correct rejections) in which performance was matched by group, a-MCI patients displayed similar neural correlates to that of the CN group, including modulation of the FN400 and the late positive complex (LPC) which are thought to index familiarity and recollection, respectively. Alternatively, when the integrity of these components was measured based on retrieval attempts (studied versus unstudied items), a-MCI patients displayed a reduced FN400 and LPC. Furthermore, modulation of the FN400 correlated with a behavioral estimate of familiarity and the LPC with a behavioral estimate of recollection obtained in a separate experiment in the same individuals, consistent with the proposed mappings of these indices. These results support a global decline of recognition memory in a-MCI, which suggests that the memory loss of prodromal AD may be qualitatively distinct from normal aging.
Keywords: memory, recollection, familiarity, event-related potentials, FN400, LPC, mild cognitive impairment, Alzheimer’s disease
Citation: Wolk DA, Manning K, Kliot D and Arnold SE (2013) Recognition memory in amnestic-mild cognitive impairment: insights from event-related potentials. Front. Aging Neurosci. 5:89. doi: 10.3389/fnagi.2013.00089
Received: 16 October 2013; Paper pending published: 07 November 2013;
Accepted: 20 November 2013; Published online: 11 December 2013.
Edited by:Hari S. Sharma, Uppsala University, Sweden
Reviewed by:Mira Didic, Assistance Publique-Hôpitaux de Marseille, INSERM, Aix-Marseille Université, France
Brandon Ally, Vanderbilt University, USA
Copyright © 2013 Wolk, Manning, Kliot and Arnold. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: David A. Wolk, Penn Memory Center, University of Pennsylvania, 3615 Chestnut Street, #212A, Philadelphia, PA 19104, USA e-mail: firstname.lastname@example.org