Isolating age-group differences in working memory load-related neural activity

Assessing the contribution of working memory capacity using a partial-trial fMRI method

Ilana J. Bennett, Hannah G. Rivera, Bart Rypma

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results.

Original languageEnglish (US)
Pages (from-to)20-32
Number of pages13
JournalNeuroImage
Volume72
DOIs
StatePublished - May 5 2013

Fingerprint

Short-Term Memory
Age Groups
Magnetic Resonance Imaging
Prefrontal Cortex
Young Adult
Neuroimaging

Keywords

  • Capacity
  • Functional magnetic resonance imaging (fMRI)
  • Healthy aging
  • Working memory

ASJC Scopus subject areas

  • Cognitive Neuroscience
  • Neurology

Cite this

Isolating age-group differences in working memory load-related neural activity : Assessing the contribution of working memory capacity using a partial-trial fMRI method. / Bennett, Ilana J.; Rivera, Hannah G.; Rypma, Bart.

In: NeuroImage, Vol. 72, 05.05.2013, p. 20-32.

Research output: Contribution to journalArticle

@article{e62daae8788340e0b338860dfe20d17c,
title = "Isolating age-group differences in working memory load-related neural activity: Assessing the contribution of working memory capacity using a partial-trial fMRI method",
abstract = "Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results.",
keywords = "Capacity, Functional magnetic resonance imaging (fMRI), Healthy aging, Working memory",
author = "Bennett, {Ilana J.} and Rivera, {Hannah G.} and Bart Rypma",
year = "2013",
month = "5",
day = "5",
doi = "10.1016/j.neuroimage.2013.01.030",
language = "English (US)",
volume = "72",
pages = "20--32",
journal = "NeuroImage",
issn = "1053-8119",
publisher = "Academic Press Inc.",

}

TY - JOUR

T1 - Isolating age-group differences in working memory load-related neural activity

T2 - Assessing the contribution of working memory capacity using a partial-trial fMRI method

AU - Bennett, Ilana J.

AU - Rivera, Hannah G.

AU - Rypma, Bart

PY - 2013/5/5

Y1 - 2013/5/5

N2 - Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results.

AB - Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results.

KW - Capacity

KW - Functional magnetic resonance imaging (fMRI)

KW - Healthy aging

KW - Working memory

UR - http://www.scopus.com/inward/record.url?scp=84873735345&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84873735345&partnerID=8YFLogxK

U2 - 10.1016/j.neuroimage.2013.01.030

DO - 10.1016/j.neuroimage.2013.01.030

M3 - Article

VL - 72

SP - 20

EP - 32

JO - NeuroImage

JF - NeuroImage

SN - 1053-8119

ER -