2.1 Participants
The study included three groups of participants including younger adults
[YA] (Total N = 29, 11 males, mean age of 21.3 ± 2.5 years, mean
education of 14.2 ±1.2 years), cognitively healthy older adults [HA]
(total N = 22, 5 males, mean age of 63.9 ± 6.4 years, mean education of
17 ± 1.6 years), and individuals with a diagnosis of mild cognitive
impairment [MCI] (total N = 20, 10 males, mean age of 67.8 ± 8.2
years, mean education of 16 ± 2.4 years; Clinical Dementia Rating of
0.5). All participants were native English speakers with no history of
learning disabilities, stroke, major psychiatric illness, alcoholism or
substance abuse, or uncorrected hearing or vision loss. All MCI
participants met Petersen criteria (Petersen et al., 2009), by consensus
diagnosis among clinicians or research investigators, including the
following: (1) cognitive concerns reported by the patient and/or
corroborated by a reliable informant, (2) cognitive impairments verified
by objective measures, (3) relative independence in performing daily
functions, and (4) did not meet dementia criteria. Both amnestic (N =
16) and non-amnestic (N = 4) MCI patients were included. The HA and MCI
groups had no statistical differences in age and education. Performance
on selected neuropsychological tests for HA and MCI is presented in
Table 1. Informed consent was obtained from all participants in
accordance with the protocols approved by the Institutional Review
Boards of The University of Texas at Dallas and The University of Texas
Southwestern Medical Center. Experiments with participants were
performed in accordance with the ethical standards of the Committee on
Human Experimentation of these institutions and with the Helsinki
Declaration of 1975.