Embodied cognition comes of age: A processing advantage for action words is modulated by aging and the task.

Processing action words (e.g., fork, throw) engages neurocognitive motor representations, consistent with embodied cognition principles. Despite age-related neurocognitive changes that could affect action words, and a rapidly aging population, the impact of healthy aging on action-word processing is poorly understood. Previous research suggests that in lexical tasks demanding semantic access, such as picture naming, higher motor-relatedness can enhance performance (e.g., fork vs. pier)-particularly in older adults, perhaps due to the age-related relative sparing of motor-semantic circuitry, which can support action words. However, motor-relatedness was recently found to affect performance in younger but not older adults in lexical decision. We hypothesized this was due to decreased semantic access in this task, especially in older adults. Here we tested effects of motor-relatedness on 2,174 words in younger and older adults not only in lexical decision but also in reading aloud, in which semantic access is minimal. Mixed-effects regression, controlling for phonological, lexical, and semantic variables, yielded results consistent with our predictions. In lexical decision, younger adults were faster and more accurate at words with higher-motor relatedness, whereas older adults showed no motor-relatedness effects. In reading aloud, neither age group showed such effects. Multiple sensitivity analyses demonstrated that the patterns were robust. Altogether, whereas previous research indicates that in lexical tasks demanding semantic access, higher motor-relatedness can enhance performance, especially in older adults, evidence now suggests that such effects are attenuated with decreased semantic access, which in turn depends on the task as well as aging itself. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Linguistic correlates of societal variation: A quantitative analysis.

Traditionally, many researchers have supported a uniformitarian view whereby all languages are of roughly equal complexity, facilitated by internal trade-offs between complexity at different levels, such as morphology and syntax. The extent to which the speakers' societies influence the trade-offs has not been well studied. In this paper, we focus on morphology and syntax, and report significant correlations between specific linguistic and societal features, in particular those relating to exoteric (open) vs. esoteric (close-knit) society types, characterizable in terms of population size, mobility, communication across distances, etc. We conduct an exhaustive quantitative analysis drawing upon WALS, D-Place, Ethnologue and Glottolog, finding some support for our hypothesis that languages spoken by exoteric societies tend towards more complex syntaxes, while languages spoken by esoteric societies tend towards more complex morphologies.

Aging affects steaks more than knives: Evidence that the processing of words related to motor skills is relatively spared in aging.

Lexical-processing declines are a hallmark of aging. However, the extent of these declines may vary as a function of different factors. Motivated by findings from neurodegenerative diseases and healthy aging, we tested whether 'motor-relatedness' (the degree to which words are associated with particular human body movements) might moderate such declines. We investigated this question by examining data from three experiments. The experiments were carried out in different languages (Dutch, German, English) using different tasks (lexical decision, picture naming), and probed verbs and nouns, in all cases controlling for potentially confounding variables (e.g., frequency, age-of-acquisition, imageability). Whereas 'non-motor words' (e.g., steak) showed age-related performance decreases in all three experiments, 'motor words' (e.g., knife) yielded either smaller decreases (in one experiment) or no decreases (in two experiments). The findings suggest that motor-relatedness can attenuate or even prevent age-related lexical declines, perhaps due to the relative sparing of neural circuitry underlying such words.

Early-life education may help bolster declarative memory in old age, especially for women.

Although declarative memory declines with age, sex and education might moderate these weaknesses. We investigated effects of sex and education on nonverbal declarative (recognition) memory in 704 older adults (aged 58-98, 0-17 years of education). Items were drawings of real and made-up objects. Age negatively impacted declarative memory, though this age effect was moderated by sex and object-type: it was steeper for males than females, but only for real objects. Education was positively associated with memory, but also interacted with sex and object-type: education benefited women more than men (countering the age effects, especially for women), and remembering real more than made-up objects. The findings suggest that nonverbal memory in older adults is associated negatively with age but positively with education; both effects are modulated by sex, and by whether learning relates to preexisting or new information. The study suggests downstream benefits from education, especially for girls.

Can sex influence the neurocognition of language? Evidence from Parkinson's disease.

Parkinson's disease (PD), which involves basal ganglia degeneration, affects language as well as motor function. However, which aspects of language are impaired in PD and under what circumstances remains unclear. We examined whether lexical and grammatical aspects of language are differentially affected in PD, and whether this dissociation is moderated by sex as well as the degree of basal ganglia degeneration. Our predictions were based on the declarative/procedural model of language. The model posits that grammatical composition, including in regular inflection, depends importantly on left basal ganglia procedural memory circuits, whereas irregular and other lexicalized forms are memorized in declarative memory. Since females tend to show declarative memory advantages as compared to males, the model further posits that females should tend to rely on this system for regulars, which can be stored as lexicalized chunks. We tested non-demented male and female PD patients and healthy control participants on the intensively studied paradigm of English regular and irregular past-tense production. Mixed-effects regression revealed PD deficits only at regular inflection, only in male patients. The degree of left basal ganglia degeneration, as reflected by right-side hypokinesia, predicted only regular inflection, and only in male patients. Left-side hypokinesia did not show this pattern. Past-tense frequency effects suggested that the female patients retrieved regular as well as irregular past-tense forms from declarative memory, whereas the males retrieved only irregulars. Sensitivity analyses showed that the pattern of findings was robust. The results, which are consistent with the declarative/procedural model, suggest a grammatical deficit in PD due to left basal ganglia degeneration, with a relative sparing of lexical retrieval. Female patients appear to compensate for this deficit by relying on chunks stored in declarative memory. More generally, the study elucidates the neurocognition of inflectional morphology and provides evidence that sex can influence how language is computed in the mind and brain.

A dissociation between syntactic and lexical processing in Parkinson's disease.

Parkinson's disease (PD), which involves the degeneration of dopaminergic neurons in the basal ganglia, has long been associated with motor deficits. Increasing evidence suggests that language can also be impaired, including aspects of syntactic and lexical processing. However, the exact pattern of these impairments remains somewhat unclear, for several reasons. Few studies have examined and compared syntactic and lexical processing within subjects, so their relative deficits remain to be elucidated. Studies have focused on earlier stages of PD, so syntactic and lexical processing in later stages are less well understood. Research has largely probed English and a handful of other European languages, and it is unclear whether findings generalize more broadly. Finally, few studies have examined links between syntactic/lexical impairments and their neurocognitive substrates, such as measures of basal ganglia degeneration or dopaminergic processes. We addressed these gaps by investigating multiple aspects of Farsi syntactic and lexical processing in 40 Farsi native-speaking moderate-to-severe non-demented PD patients, and 40 healthy controls. Analyses revealed equivalent impairments of syntactic comprehension and syntactic judgment, across different syntactic structures. Lexical processing was impaired only for motor function-related objects (e.g., naming 'hammer', but not 'mountain'), in line with findings of PD deficits at naming action verbs as compared to objects, without the verb/noun confound. In direct comparisons between lexical and syntactic tasks, patients were better at naming words like 'mountain' (but not words like 'hammer') than at syntactic comprehension and syntactic judgment. Performance at syntactic comprehension correlated with the last levodopa equivalent dose. No other correlations were found between syntactic/lexical processing measures and either levodopa equivalent dose or hypokinesia, which reflects degeneration of basal ganglia motor-related circuits. All critical significant main effects, interactions, and correlations yielded large effect sizes. The findings elucidate the nature of syntactic and lexical processing impairments in PD.

Sex, dopamine, and hypokinesia: A study of inflectional morphology in Parkinson's disease.

OBJECTIVE: Parkinson's disease (PD), which involves the degeneration of dopaminergic basal ganglia neurons, appears to affect language. We investigated which aspects of language are impaired in PD and what moderates these impairments. Our predictions were based on the declarative/procedural model of language, which links grammar, including in regular inflection, to procedural memory and left-lateralized basal ganglia dopaminergic circuits but links lexical memory, including irregulars, to declarative memory. Because females tend to show declarative memory advantages as compared to males, the model predicts that females rely more on this system for regulars, which can be stored as chunks. METHOD: We probed regular/irregular Farsi past-tense production in 40 Farsi-speaking patients with moderate-to-severe nondemented PD (half female) and 40 normal controls (half female). RESULTS: Consistent with our predictions, we found that male, but not female, PD patients showed greater deficits at regular than irregular past-tense production. The females' impairment was mildest for regulars, likely from compensatory storage, as revealed by regular past-tense frequency effects only in females. Right-side hypokinesia (linked to left basal ganglia degeneration) correlated negatively with accuracy of regulars but not irregulars. Similarly, the levodopa equivalent dose of patients' last medication correlated only with regulars. CONCLUSIONS: The results suggest that language is impaired in PD, but the impairments are moderated by multiple factors, including the type of linguistic knowledge, the degree of left basal ganglia degeneration, dopamine, and sex. The findings underscore the impact of sex on the neurocognition of language and the roles of left basal ganglia dopaminergic circuits in aspects of rule-governed grammar. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Effects of Aging on Interference During Pronoun Resolution.

Purpose: The purpose of this study is to investigate the effects of healthy aging on the ability to suppress grammatically illicit antecedents during pronoun resolution. Method: In 2 reading-based acceptability-judgment experiments, younger and older speakers of German read sentences containing an object pronoun and 2 potential antecedent noun phrases, only 1 of which was a grammatically licit antecedent. Using a gender-mismatch paradigm, we compared to what extent younger and older speakers were sensitive to feature (mis)matches between the pronoun and either of the 2 antecedents. All participants were fluent readers of German and had finished at least secondary education. Results: Experiment 1 used a self-paced reading paradigm. Older speakers showed greater sensitivity than younger ones to mismatching licit antecedents, but no group showed any evidence of interference from an intervening competitor antecedent. In Experiment 2, we increased the processing demand by using paced word-by-word stimulus presentation and longer sentences. Here, older participants showed reduced sensitivity, in comparison with younger people, to mismatching licit antecedents. Unlike our younger participants, they showed signs of distraction by the presence of a linearly closer but grammatically inappropriate antecedent when no appropriate antecedent was available. Conclusion: Together, our results show that older (but not younger) speakers' ability to compute intrasentential referential dependencies is vulnerable to increased task demands. We briefly discuss a potential role for executive functions, such as interference control.

Agreement processing and attraction errors in aging: evidence from subject-verb agreement in German.

Effects of aging on lexical processing are well attested, but the picture is less clear for grammatical processing. Where age differences emerge, these are usually ascribed to working-memory (WM) decline. Previous studies on the influence of WM on agreement computation have yielded inconclusive results, and work on aging and subject-verb agreement processing is lacking. In two experiments (Experiment 1: timed grammaticality judgment, Experiment 2: self-paced reading + WM test), we investigated older (OA) and younger (YA) adults' susceptibility to agreement attraction errors. We found longer reading latencies and judgment reaction times (RTs) for OAs. Further, OAs, particularly those with low WM scores, were more accepting of sentences with attraction errors than YAs. OAs showed longer reading latencies for ungrammatical sentences, again modulated by WM, than YAs. Our results indicate that OAs have greater difficulty blocking intervening nouns from interfering with the computation of agreement dependencies. WM can modulate this effect.