The Effects of Age and Culture on Default Network Function: Frontal Compensation With Age; Modulation Differences Across Culture

Examining age and culture effects offers a unique perspective into brain function. In the current set of experiments, the effects of age (young and old) and culture (East Asian and Western) on the activity of the default network was examined in a memory encoding paradigm. With respect to age, it was theorized that suppression deficits in older adults would be compensated for by enhanced frontal recruitment. With respect to culture, a novel framework was proposed predicting modulation differences in default network function. The proposal predicted that chronic attention to context in the East Asians would result in less modulation of the default network in rest versus active cognitive states relative to Westerners. Results confirmed both hypotheses. First, increased frontal recruitment was correlated with suppression deficits in older adults. This correlation appeared only in the better performing older adults suggesting that frontal activity was engaged to compensate for default suppression deficits in the older adults. Further, the frontal default compensatory relationship appeared in the better performing older adults of both cultures, suggesting it may be a common age-related occurrence. Second, younger Western adults showed substantially greater default suppression during high confidence remembered trials relative to forgotten trials, whereas younger East Asians showed limited signs of default modulation across these trials, consistent with the proposed hypothesis.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Psychology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Leshikar, Eric Duane

Contributors dc:contributor

• Park, Denise C.

• Psychology, Psychobiology

Language dc:language

eng

Identifier

(MiAaPQ)AAI3392187

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/82190