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Age-Related Changes in Predictive Capacity Versus Internal Model Adaptability: Electrophysiological Evidence that Individual Differences Outweigh Effects of Age.

Bornkessel-Schlesewsky I, Philipp M, Alday PM, Kretzschmar F, Grewe T, Gumpert M, Schumacher PB, Schlesewsky M - Front Aging Neurosci (2015)

Bottom Line: Event-related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target-related P300 for the expected antonym ("white"; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, "nice," versus the incongruous associated condition, "yellow").However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items.We thus argue that - at both a neurophysiological and a functional level - the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive performance.

View Article: PubMed Central - PubMed

Affiliation: Cognitive Neuroscience Laboratory, School of Psychology, Social Work and Social Policy, University of South Australia, Adelaide SA, Australia.

ABSTRACT
Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age-related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event-related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target-related P300 for the expected antonym ("white"; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, "nice," versus the incongruous associated condition, "yellow"). These effects were followed by a late positivity, again with a larger amplitude in the incongruous non-associated versus incongruous associated condition. Analyses using linear mixed-effects models showed that the target-related P300 effect and the N400 effect for the incongruous non-associated condition were both modulated by age, thus suggesting that age-related changes affect both prediction generation and model adaptation. However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items. We thus argue that - at both a neurophysiological and a functional level - the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive performance.

No MeSH data available.


Related in: MedlinePlus

Visualisation of fixed effects estimates for the best-fitting model for the reaction times. Dots represent the estimated coefficient value; lines show standard deviations of coefficients (black lines) and 95% confidence intervals (CIs, 2 standard deviations; grey lines). Note that when the CI for a given effect does not cross the zero mark, this effect is considered statistically significant.
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Figure 1: Visualisation of fixed effects estimates for the best-fitting model for the reaction times. Dots represent the estimated coefficient value; lines show standard deviations of coefficients (black lines) and 95% confidence intervals (CIs, 2 standard deviations; grey lines). Note that when the CI for a given effect does not cross the zero mark, this effect is considered statistically significant.

Mentions: Mean reaction times (calculated for correctly answered trials only) were as follows (by-participant standard deviations are given in parentheses): ANT 642 ms (221); REL 781 ms (247); NONREL 622 ms (211). As the REL condition was the main source of variability in the reaction times, LMM analyses were only performed using the match–incongruous_associated contrasts (i.e., comparing ANT and REL to the grand mean of the reaction times). Iterative model fits revealed that a model including the fixed factors COND and AGE as well as their interaction, and per-condition random slopes for participants and items showed the best fit to the data. The fixed effects are visualized in Figure 1; for a full model specification and Wald χ2–statistics for the fixed effects in the model, see Supplementary Tables S1 and S2, respectively. The main effect of COND and the interaction of COND × AGE reached significance, with the interaction resulting from an effect of age particularly on the REL condition.


Age-Related Changes in Predictive Capacity Versus Internal Model Adaptability: Electrophysiological Evidence that Individual Differences Outweigh Effects of Age.

Bornkessel-Schlesewsky I, Philipp M, Alday PM, Kretzschmar F, Grewe T, Gumpert M, Schumacher PB, Schlesewsky M - Front Aging Neurosci (2015)

Visualisation of fixed effects estimates for the best-fitting model for the reaction times. Dots represent the estimated coefficient value; lines show standard deviations of coefficients (black lines) and 95% confidence intervals (CIs, 2 standard deviations; grey lines). Note that when the CI for a given effect does not cross the zero mark, this effect is considered statistically significant.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4663277&req=5

Figure 1: Visualisation of fixed effects estimates for the best-fitting model for the reaction times. Dots represent the estimated coefficient value; lines show standard deviations of coefficients (black lines) and 95% confidence intervals (CIs, 2 standard deviations; grey lines). Note that when the CI for a given effect does not cross the zero mark, this effect is considered statistically significant.
Mentions: Mean reaction times (calculated for correctly answered trials only) were as follows (by-participant standard deviations are given in parentheses): ANT 642 ms (221); REL 781 ms (247); NONREL 622 ms (211). As the REL condition was the main source of variability in the reaction times, LMM analyses were only performed using the match–incongruous_associated contrasts (i.e., comparing ANT and REL to the grand mean of the reaction times). Iterative model fits revealed that a model including the fixed factors COND and AGE as well as their interaction, and per-condition random slopes for participants and items showed the best fit to the data. The fixed effects are visualized in Figure 1; for a full model specification and Wald χ2–statistics for the fixed effects in the model, see Supplementary Tables S1 and S2, respectively. The main effect of COND and the interaction of COND × AGE reached significance, with the interaction resulting from an effect of age particularly on the REL condition.

Bottom Line: Event-related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target-related P300 for the expected antonym ("white"; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, "nice," versus the incongruous associated condition, "yellow").However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items.We thus argue that - at both a neurophysiological and a functional level - the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive performance.

View Article: PubMed Central - PubMed

Affiliation: Cognitive Neuroscience Laboratory, School of Psychology, Social Work and Social Policy, University of South Australia, Adelaide SA, Australia.

ABSTRACT
Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age-related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event-related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target-related P300 for the expected antonym ("white"; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, "nice," versus the incongruous associated condition, "yellow"). These effects were followed by a late positivity, again with a larger amplitude in the incongruous non-associated versus incongruous associated condition. Analyses using linear mixed-effects models showed that the target-related P300 effect and the N400 effect for the incongruous non-associated condition were both modulated by age, thus suggesting that age-related changes affect both prediction generation and model adaptation. However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items. We thus argue that - at both a neurophysiological and a functional level - the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive performance.

No MeSH data available.


Related in: MedlinePlus