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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 (IAF) model of ERP amplitudes in the LPS time window. See Figure 1 for a guide to interpreting the figure.
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Figure 5: Visualisation of fixed effects estimates for the best-fitting (IAF) model of ERP amplitudes in the LPS time window. See Figure 1 for a guide to interpreting the figure.

Mentions: In contrast to the earlier time window, the best-fitting LMM for the late positivity window included IAF rather than COND. As with all previous models, by-condition random slopes for participants and items substantially improved model fits. The three-way interaction of COND × ROI × IAF did not reach significance and was removed from the model without a significant loss of explanatory capacity. Accordingly, the minimal adequate model for the LPS time window included IAF and by-condition random slopes, but no three-way interaction. The fixed effects in the best-fitting model are shown in Figure 5 (see Supplementary Tables S8 and S9 for a full model summary and Wald χ2–statistics for the fixed effects in the model, respectively). As is apparent from the figure, the main effect of COND and the interaction COND × ROI reached significance, with the interaction due to a positivity for the NONREL condition and a relative negativity for the ANT condition in posterior ROIs. At anterior sites, there is an amplitude reversal, which appears to result from effects in the later part of the time window (i.e., a relative negativity for the ANT condition in comparison to the other two conditions; see Figure 2). While there was a main effect of IAF and an interaction of IAF × ROI, there was no interaction between IAF and COND.


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 (IAF) model of ERP amplitudes in the LPS time window. See Figure 1 for a guide to interpreting the figure.
© Copyright Policy
Related In: Results  -  Collection

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

Figure 5: Visualisation of fixed effects estimates for the best-fitting (IAF) model of ERP amplitudes in the LPS time window. See Figure 1 for a guide to interpreting the figure.
Mentions: In contrast to the earlier time window, the best-fitting LMM for the late positivity window included IAF rather than COND. As with all previous models, by-condition random slopes for participants and items substantially improved model fits. The three-way interaction of COND × ROI × IAF did not reach significance and was removed from the model without a significant loss of explanatory capacity. Accordingly, the minimal adequate model for the LPS time window included IAF and by-condition random slopes, but no three-way interaction. The fixed effects in the best-fitting model are shown in Figure 5 (see Supplementary Tables S8 and S9 for a full model summary and Wald χ2–statistics for the fixed effects in the model, respectively). As is apparent from the figure, the main effect of COND and the interaction COND × ROI reached significance, with the interaction due to a positivity for the NONREL condition and a relative negativity for the ANT condition in posterior ROIs. At anterior sites, there is an amplitude reversal, which appears to result from effects in the later part of the time window (i.e., a relative negativity for the ANT condition in comparison to the other two conditions; see Figure 2). While there was a main effect of IAF and an interaction of IAF × ROI, there was no interaction between IAF and COND.

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