Abstract
The current study reports the effects of accumulating contextual constraints on neural indices of lexico-semantic processing (i.e., effects of word frequency and orthographic neighborhood) as a function of normal aging. Event-related brain potentials were measured from a sample of older adults as they read sentences that were semantically congruent, provided only syntactic constraints (syntactic prose), or were random word strings. A linear mixed-effects modeling approach was used to probe the effects of accumulating contextual constraints on N400 responses to individual words. Like young adults in prior work, older adults exhibited a classic word position context effect on the N400 in congruent sentences, although the magnitude of the effect was reduced in older relative to younger adults. Moreover, by modeling single-word variability in N400 responses, we observed robust effects of orthographic neighborhood density that were larger in older adults than the young, and preserved effects word frequency. Importantly, in older adults, frequency effects were not modulated by accumulating contextual constraints, unlike in the young. Collectively, these findings indicate that older adults are less likely (or able) to use accumulating top-down contextual constraints, and therefore rely more strongly on bottom-up lexical features to guide semantic access of individual words during sentence comprehension.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 117-128 |
| Number of pages | 12 |
| Journal | Brain Research |
| Volume | 1687 |
| DOIs | |
| State | Published - May 15 2018 |
Fingerprint
Keywords
- Aging
- Context
- ERP
- Language
- N400
- Semantic memory
ASJC Scopus subject areas
- Neuroscience(all)
- Molecular Biology
- Clinical Neurology
- Developmental Biology
Cite this
Contextual constraints on lexico-semantic processing in aging : Evidence from single-word event-related brain potentials. / Payne, Brennan R.; Federmeier, Kara D.
In: Brain Research, Vol. 1687, 15.05.2018, p. 117-128.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Contextual constraints on lexico-semantic processing in aging
T2 - Evidence from single-word event-related brain potentials
AU - Payne, Brennan R.
AU - Federmeier, Kara D
PY - 2018/5/15
Y1 - 2018/5/15
N2 - The current study reports the effects of accumulating contextual constraints on neural indices of lexico-semantic processing (i.e., effects of word frequency and orthographic neighborhood) as a function of normal aging. Event-related brain potentials were measured from a sample of older adults as they read sentences that were semantically congruent, provided only syntactic constraints (syntactic prose), or were random word strings. A linear mixed-effects modeling approach was used to probe the effects of accumulating contextual constraints on N400 responses to individual words. Like young adults in prior work, older adults exhibited a classic word position context effect on the N400 in congruent sentences, although the magnitude of the effect was reduced in older relative to younger adults. Moreover, by modeling single-word variability in N400 responses, we observed robust effects of orthographic neighborhood density that were larger in older adults than the young, and preserved effects word frequency. Importantly, in older adults, frequency effects were not modulated by accumulating contextual constraints, unlike in the young. Collectively, these findings indicate that older adults are less likely (or able) to use accumulating top-down contextual constraints, and therefore rely more strongly on bottom-up lexical features to guide semantic access of individual words during sentence comprehension.
AB - The current study reports the effects of accumulating contextual constraints on neural indices of lexico-semantic processing (i.e., effects of word frequency and orthographic neighborhood) as a function of normal aging. Event-related brain potentials were measured from a sample of older adults as they read sentences that were semantically congruent, provided only syntactic constraints (syntactic prose), or were random word strings. A linear mixed-effects modeling approach was used to probe the effects of accumulating contextual constraints on N400 responses to individual words. Like young adults in prior work, older adults exhibited a classic word position context effect on the N400 in congruent sentences, although the magnitude of the effect was reduced in older relative to younger adults. Moreover, by modeling single-word variability in N400 responses, we observed robust effects of orthographic neighborhood density that were larger in older adults than the young, and preserved effects word frequency. Importantly, in older adults, frequency effects were not modulated by accumulating contextual constraints, unlike in the young. Collectively, these findings indicate that older adults are less likely (or able) to use accumulating top-down contextual constraints, and therefore rely more strongly on bottom-up lexical features to guide semantic access of individual words during sentence comprehension.
KW - Aging
KW - Context
KW - ERP
KW - Language
KW - N400
KW - Semantic memory
UR - http://www.scopus.com/inward/record.url?scp=85043385170&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85043385170&partnerID=8YFLogxK
U2 - 10.1016/j.brainres.2018.02.021
DO - 10.1016/j.brainres.2018.02.021
M3 - Article
VL - 1687
SP - 117
EP - 128
JO - Brain Research
JF - Brain Research
SN - 0006-8993
ER -