Title:Age-related Differences in Mu Rhythm During Emotional Destination Memory Task
Volume: 15
Issue: 1
Author(s): Anastasia Kladi, Paraskevi Iliadou*, Magdalini Tsolaki and Despoina Moraitou
Affiliation:
- Department of Experimental and Cognitive Psychology, School of Psychology, Aristotle University of Thessaloniki,
Thessaloniki, Greece
- Laboratory of Neurodegenerative Diseases, Center for Interdisciplinary Research and Innovation
(CIRI – AUTH) Balkan Center, Aristotle University of Thessaloniki, Thessaloniki, Greece
Keywords:
Mirror neurons, Mu suppression, destination memory, emotional charging, young adults, older adults.
Abstract:
Background: Destination memory defined as the ability to remember to whom we addressed
a piece of information is found to be impaired in normal aging. Theories of affect development
and research findings have shown that emotional charging improves performance on memory
tasks, and also that Mu rhythm is desynchronized as an index of mirror neuron activation during
such tasks.
Objective: In this paper, we sought to investigate the differences in Mu rhythm during an emotional
destination memory task, between younger and older adults.
Methods: 16 cognitively normal older adults, recruited from Alzheimer’s disease day center and 16
young adults, recruited via advertisements, participated in this experimental study. We investigated
destination memory of emotionally charged faces (Emotional Destination Memory, EDM) while applying
electroencephalograph (EEG) in real time in young versus older adults. We measured Mu
rhythm in frontal, fronto-temporal and central areas. EEG data has been pre-processed, segmented
in non-overlapping epochs, and independent component analysis (ICA) has been conducted to reject
artifacts.
Results: Results showed that young adults performed better than older adults in remembering facts
associated with angry faces. Also, different neurophysiological activation was found, with older
adults showing Mu suppression in frontal and fronto-temporal regions, specifically in F3, F7 and
F8 electrodes, in contrast with young adults who showed Mu enhancement. Regarding within
group differences, it was found that in the older adults group, electrodes F8 and central C3 were
the most activated, while in the young adults group, C3 was the most activated electrode.
Conclusion: The findings suggest better behavioral performance of young adults as a result of better
cognitive state and adaptive bias. On a neurophysiological level, it is suggested that older adults
employ Mu suppression, thus possible activation of mirror neurons, as a compensatory mechanism
while mirroring properties are not spontaneously activated in young adults.