Impaired language in Alzheimer's disease: A comparison between English and Persian implicates content-word frequency rather than the noun-verb distinction.

This study challenges the conventional psycholinguistic view that the distinction between nouns and verbs is pivotal in understanding language impairments in neurological disorders. Traditional views link frontal brain region damage with verb processing deficits and posterior temporoparietal damage with noun difficulties. However, this perspective is contested by findings from patients with Alzheimer's disease (pwAD), who show impairments in both word classes despite their typical temporoparietal atrophy. Notably, pwAD tend to use semantically lighter verbs in their speech than healthy individuals. By examining English-speaking pwAD and comparing them with Persian-speaking pwAD, this research aims to demonstrate that language impairments in Alzheimer's disease (AD) stem from the distributional properties of words within a language rather than distinct neural processing networks for nouns and verbs. We propose that the primary deficit in AD language production is an overreliance on high-frequency words. English has a set of particularly high-frequency verbs that surpass most nouns in usage frequency. Since pwAD tend to use high-frequency words, the byproduct of this word distribution in the English language would be an over-usage of high-frequency verbs. In contrast, Persian features complex verbs with an overall distribution lacking extremely high-frequency verbs like those found in English. As a result, we hypothesize that Persian-speaking pwAD would not have a bias toward the overuse of high-frequency verbs. We analyzed language samples from 95 English-speaking pwAD and 91 healthy controls, along with 27 Persian-speaking pwAD and 27 healthy controls. Employing uniform automated natural language processing methods, we measured the usage rates of nouns, verbs, and word frequencies across both cohorts. Our findings showed that English-speaking pwAD use higher-frequency verbs than healthy individuals, a pattern not mirrored by Persian-speaking pwAD. Crucially, we found a significant interaction between the frequencies of verbs used by English and Persian speakers with and without AD. Moreover, regression models that treated noun and verb frequencies as separate predictors did not outperform models that considered overall word frequency alone in classifying AD. In conclusion, this study suggests that language abnormalities among English-speaking pwAD reflect the unique distributional properties of words in English rather than a universal noun-verb class distinction. Beyond offering a new understanding of language abnormalities in AD, the study highlights the critical need for further investigation across diverse languages to deepen our insight into the mechanisms of language impairments in neurological disorders.

Word meaning is complex: Language-related generalization differences in autistic adults.

The current study marries two important observations. First, there is a growing recognition that word meanings need to be flexibly extended in new ways as new contexts arise. Second, as evidenced primarily within the perceptual domain, autistic individuals tend to find generalization more challenging while showing stronger veridical memory in comparison to their neurotypical peers. Here we report that a group of 80 autistic adults finds it more challenging to flexibly extend the meanings of familiar words in new ways than a group of 80 neurotypical peers, while the autistic individuals outperform the neurotypicals on a novel word-learning task that does not require flexible extension. Results indicate that recognized differences in generalization present an ongoing challenge for autistic adults in the domain of language, separate from social cognition, executive function, or the ability to assign single fixed meanings to new words.

The discourse functions of grammatical constructions explain an enduring syntactic puzzle.

Each grammatical construction serves a function, such as conveying that part an utterance is at-issue or is backgrounded. When multiple constructions combine to produce an utterance, their functions must be compatible. This preregistered study (N = 680) addresses the enigmatic case of "syntactic island constraints": Long-distance dependency constructions (LDDs) do not combine equally well with all base constructions. While widely presumed to require unlearned syntactic constraints, we test the idea that it is infelicitous to make an element both prominent (via an LDD construction) and backgrounded (via the base construction). Using 10 base constructions of English (144 base stimuli), results confirm two independent measures of backgroundedness strongly correlate with acceptability ratings on each of three LDD constructions. Results indicate that "island" constraints arise from a clash between the functions of the constructions being combined.

From partners to populations: A hierarchical Bayesian account of coordination and convention.

Languages are powerful solutions to coordination problems: They provide stable, shared expectations about how the words we say correspond to the beliefs and intentions in our heads. Yet, language use in a variable and nonstationary social environment requires linguistic representations to be flexible: Old words acquire new ad hoc or partner-specific meanings on the fly. In this article, we introduce continual hierarchical adaptation through inference (CHAI), a hierarchical Bayesian theory of coordination and convention formation that aims to reconcile the long-standing tension between these two basic observations. We argue that the central computational problem of communication is not simply transmission, as in classical formulations, but continual learning and adaptation over multiple timescales. Partner-specific common ground quickly emerges from social inferences within dyadic interactions, while community-wide social conventions are stable priors that have been abstracted away from interactions with multiple partners. We present new empirical data alongside simulations showing how our model provides a computational foundation for several phenomena that have posed a challenge for previous accounts: (a) the convergence to more efficient referring expressions across repeated interaction with the same partner, (b) the gradual transfer of partner-specific common ground to strangers, and (c) the influence of communicative context on which conventions eventually form. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Good-enough language production.

Our ability to comprehend and produce language is one of humans' most impressive skills, but it is not flawless. We must convey and interpret messages via a noisy channel in ever-changing contexts and we sometimes fail to access an optimal combination of words and grammatical constructions. Here, we extend the notion of good-enough (GN) comprehension to GN production, which allows us to unify a wide range of phenomena including overly vague word choices, agreement errors, resumptive pronouns, transfer effects, and children's overextensions and regularizations. We suggest these all involve the accessing and production of a 'GN' option when a more-optimal option is inaccessible. The role of accessibility highlights the need to relate memory encoding and retrieval processes to language comprehension and production.

Accessibility and Historical Change: An Emergent Cluster Led Uncles and Aunts to Become Aunts and Uncles.

There are times when a curiously odd relic of language presents us with a thread, which when pulled, reveals deep and general facts about human language. This paper unspools such a case. Prior to 1930, English speakers uniformly preferred male-before-female word order in conjoined nouns such as uncles and aunts; nephews and nieces; men and women. Since then, at least a half dozen items have systematically reversed their preferred order (e.g., aunts and uncles, nieces and nephews) while others have not (men and women). We review evidence that the unusual reversals began with mother and dad(dy) and spread to semantically and morphologically related binomials over a period of decades. The present work proposes that three aspects of cognitive accessibility combine to quantify the probability of A&B order: (1) the relative accessibility of the A&B terms individually, (2) competition from B&A order, and critically, (3) cluster strength (i.e., similarity to related A'&B' cases). The emergent cluster of female-first binomials highlights the influence of semantic neighborhoods in memory retrieval. We suggest that cognitive accessibility can be used to predict the word order of both familiar and novel binomials generally, as well as the diachronic change focused on here.

Brief Report: Children on the Autism Spectrum are Challenged by Complex Word Meanings.

The current work suggests that two factors conspire to make vocabulary learning challenging for youth on the Autism spectrum: (1) a tendency to focus on specifics rather than on relationships among entities and (2) the fact that most words are associated with distinct but related meanings (e.g. baseball cap, pen cap, bottle cap). Neurotypical (NT) children find it easier to learn multiple related meanings of words (polysemy) in comparison to multiple unrelated meanings (homonymy). We exposed 60 NT children and 40 verbal youth on the Autism spectrum to novel words. The groups' performance learning homonyms was comparable, but unlike their NT peers, youth on the spectrum did not display the same advantage for learning polysemous words compared to homonyms.

Children make use of relationships across meanings in word learning.

Many words are associated with more than a single meaning. Words are sometimes "ambiguous," applying to unrelated meanings, but the majority of frequent words are "polysemous" in that they apply to multiple related meanings. In a preregistered design that included 2 tasks, we tested adults' and 4.5- to 7-year-old children's ability to learn 4 novel polysemous words or 4 novel ambiguous words. Both children and adults demonstrated a polysemy over ambiguity learning advantage on each task after exposure, showing better learning of novel words with multiple related meanings than novel words with unrelated meanings. Stimuli in the polysemy condition were designed and then normed to guard against learners relying on a simple definition to distinguish the multiple target meanings for each word from foils. We retested available participants after a week-long delay without providing additional exposure and found that adults' performance remained strong in the polysemy condition in 1 task, and children's performance remained strong in the polysemy condition in both tasks. We conclude that participants are adept at learning polysemous words that vary along multiple dimensions. Current results are consistent with the idea that ambiguous meanings of a word compete, but polysemous meanings instead reinforce one another. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Metaphorical language processing and amygdala activation in L1 and L2.

The present study aims to investigate the neural correlates of processing conventional figurative language in non-native speakers in a comparison with native speakers. Italian proficient L2 learners of German and German native speakers read conventional metaphorical statements as well as literal paraphrases that were comparable on a range of psycholinguistic variables. Results confirm previous findings that native speakers show increased activity for metaphorical processing, and left amygdala activation increases with increasing Metaphoricity. At the whole-brain level, L2 learners showed the expected overall differences in activation when compared to native speakers (in the fronto-temporal network). But L2 speakers did not show any distinctive activation outside the caudate nucleus as Metaphoricity increased, suggesting that the L2 speakers were less affected by increasing Metaphoricity than native speakers were. With small volume correction, only a single peak in the amygdala reached threshold for L2 speakers as Metaphoricity increased. The findings are consistent with the view that metaphorical language is more engaging for native speakers but not necessarily for L2 speakers.

How abstract is syntax? Evidence from structural priming.

In 1990, Bock and Loebell found that passives (e.g., The 747 was radioed by the airport's control tower) can be primed by intransitive locatives (e.g., The 747 was landing by the airport's control tower). This finding is often taken as strong evidence that structural priming occurs on the basis of a syntactic phrase structure that abstracts across lexical content, including prepositions, and is uninfluenced by the semantic roles of the arguments. However, all of the intransitive locative primes in Bock and Loebell contained the preposition by (by-locatives), just like the passive targets. Therefore, the locative-to-passive priming may have been due to the adjunct headed by by, rather than being a result of purely abstract syntax. The present experiment investigates this possibility. We find that passives and intransitive by-locatives are equivalent primes, but intransitive locatives with other prepositions (e.g., The 747 has landed near the airport control tower) do not prime passives. We conclude that a shared abstract, content-less tree structure is not sufficient for passive priming to occur. We then review the prior results that have been offered in favor of abstract tree priming, and note the range of evidence can be considerably narrowed-and possibly eliminated-once effects of animacy, semantic event structure, shared morphology, information structure, and rhythm are taken into account.

The blowfish effect: children and adults use atypical exemplars to infer more narrow categories during word learning.

Learners preferentially interpret novel nouns at the basic level ('dog') rather than at a more narrow level ('Labrador'). This 'basic-level bias' is mitigated by statistics: children and adults are more likely to interpret a novel noun at a more narrow label if they witness 'a suspicious coincidence' - the word applied to three exemplars of the same narrow category. Independent work has found that exemplar typicality influences learners' inferences and category learning. We bring these lines of work together to investigate whether the content (typicality) of a single exemplar affects the level of interpretation of words and whether an atypicality effect interacts with input statistics. Results demonstrate that both four- to five-year-olds and adults tend to assign a narrower interpretation to a word if it is exemplified by an atypical category member. This atypicality effect is roughly as strong as, and independent of, the suspicious coincidence effect, which is replicated.

When regularization gets it wrong: children over-simplify language input only in production.

Children tend to regularize their productions when exposed to artificial languages, an advantageous response to unpredictable variation. But generalizations in natural languages are typically conditioned by factors that children ultimately learn. In two experiments, adult and six-year-old learners witnessed two novel classifiers, probabilistically conditioned by semantics. Whereas adults displayed high accuracy in their productions - applying the semantic criteria to familiar and novel items - children were oblivious to the semantic conditioning. Instead, children regularized their productions, over-relying on only one classifier. However, in a two-alternative forced-choice task, children's performance revealed greater respect for the system's complexity: they selected both classifiers equally, without bias toward one or the other, and displayed better accuracy on familiar items. Given that natural languages are conditioned by multiple factors that children successfully learn, we suggest that their tendency to simplify in production stems from retrieval difficulty when a complex system has not yet been fully learned.

Linguistic generalization on the basis of function and constraints on the basis of statistical preemption.

How do people learn to use language in creative but constrained ways? Experiment 1 investigates linguistic creativity by exposing adult participants to two novel word order constructions that differ in terms of their semantics: One construction exclusively describes actions that have a strong effect; the other construction describes actions with a weaker but otherwise similar effect. One group of participants witnessed novel verbs only appearing in one construction or the other, while another group witnessed a minority of verbs alternating between constructions. Subsequent production and judgment results demonstrate that participants in both conditions extended and accepted verbs in whichever construction best described the intended message. Unlike related previous work, this finding is not naturally attributable to prior knowledge of the likely division of labor between verbs and constructions or to a difference in cue validity. In order to investigate how speakers learn to constrain generalizations, Experiment 2 includes one verb (out of 6) that was witnessed in a single construction to describe both strong and weak effects, essentially statistically preempting the use of the other construction. In this case, participants were much more lexically conservative with this verb and other verbs, while they nonetheless displayed an appreciation of the distinct semantics of the constructions with new novel verbs. Results indicate that the need to better express an intended message encourages generalization, while statistical preemption constrains generalization by providing evidence that verbs are restricted in their distribution.

One Among Many: Anaphoric One and Its Relationship With Numeral One.

One anaphora (e.g., this is a good one) has been used as a key diagnostic in syntactic analyses of the English noun phrase, and "one-replacement" has also figured prominently in debates about the learnability of language. However, much of this work has been based on faulty premises, as a few perceptive researchers, including Ray Jackendoff, have made clear. Abandoning the view of anaphoric one (a-one) as a form of syntactic replacement allows us to take a fresh look at various uses of the word one. In the present work, we investigate its use as a cardinal number (1-one) in order to better understand its anaphoric use. Like all cardinal numbers, 1-one can only quantify an individuated entity and provides an indefinite reading by default. Owing to unique combinatoric properties, cardinal numbers defy consistent classification as determiners, quantifiers, adjectives, or nouns. Once the semantics and distribution of cardinal numbers, including 1-one, are appreciated, many properties of a-one follow with minimal stipulation. We claim that 1-one and a-one are distinct but very closely related lexemes. When 1-one appears without a noun (e.g., Take one), it is nearly indistinguishable from a-one (e.g., take one)-the only differences being interpretive (1-one foregrounds its cardinality while a-one does not) and prosodic (presence versus absence of primary accent). While we ultimately argue that a family of constructions is required to describe the full range of syntactic contexts in which one appears, the proposed network accounts for properties of a-one by allowing it to inherit most of its syntactic and interpretive constraints from its historical predecessor, 1-one.

Neural systems involved in processing novel linguistic constructions and their visual referents.

In language, abstract phrasal patterns provide an important source of meaning, but little is known about whether or how such constructions are used to predict upcoming visual scenes. Findings from two fMRI studies indicate that initial exposure to a novel construction allows its semantics to be used for such predictions. Specifically, greater activity in the ventral striatum, a region sensitive to prediction errors, was linked to worse overall comprehension of a novel construction. Moreover, activity in occipital cortex was attenuated when a visual event could be inferred from a learned construction, which may reflect predictive coding of the event. These effects disappeared when predictions were unlikely: that is, when phrases provided no additional information about visual events. These findings support the idea that learners create and evaluate predictions about new instances during comprehension of novel linguistic constructions.

Conventional metaphors in longer passages evoke affective brain response.

Conventional metaphorical sentences such as She's asweetchild have been found to elicit greater amygdala activation than matched literal sentences (e.g., She's akindchild). In the present fMRI study, this finding is strengthened and extended with naturalistic stimuli involving longer passages and a range of conventional metaphors. In particular, a greater number of activation peaks (four) were found in the bilateral amygdala when passages containing conventional metaphors were read than when their matched literal versions were read (a single peak); while the direct contrast between metaphorical and literal passages did not show significant amygdala activation, parametric analysis revealed that BOLD signal changes in the left amygdala correlated with an increase in metaphoricity ratings across all stories. Moreover, while a measure of complexity was positively correlated with an increase in activation of a broad bilateral network mainly involving the temporal lobes, complexity was not predictive of amygdala activity. Thus, the results suggest that amygdala activation is not simply a result of stronger overall activity related to language comprehension, but is more specific to the processing of metaphorical language. SIGNIFICANCE STATEMENT: This work is the first to show that conventional metaphorical language in naturalistic longer passages that includes a range of metaphors elicits more activation in the amygdala-an area recognized to be involved in emotional processing-than carefully matched literal control passages. We probe this finding with parametric analyses using a measure of syntactic complexity and subjective judgments of metaphoricity. While complexity correlates with more overall bilateral activation of the temporal lobes, it does not correlate with amygdala activation. Instead, amygdala activation correlates with metaphoricity, suggesting that the increase in emotional salience is specific to metaphoricity and is not simply a result of an overall increase in brain activity in regions associated with language comprehension.

Subtle Implicit Language Facts Emerge from the Functions of Constructions.

Much has been written about the unlikelihood of innate, syntax-specific, universal knowledge of language (Universal Grammar) on the grounds that it is biologically implausible, unresponsive to cross-linguistic facts, theoretically inelegant, and implausible and unnecessary from the perspective of language acquisition. While relevant, much of this discussion fails to address the sorts of facts that generative linguists often take as evidence in favor of the Universal Grammar Hypothesis: subtle, intricate, knowledge about language that speakers implicitly know without being taught. This paper revisits a few often-cited such cases and argues that, although the facts are sometimes even more complex and subtle than is generally appreciated, appeals to Universal Grammar fail to explain the phenomena. Instead, such facts are strongly motivated by the functions of the constructions involved. The following specific cases are discussed: (a) the distribution and interpretation of anaphoric one, (b) constraints on long-distance dependencies,

Metaphorical sentences are more emotionally engaging than their literal counterparts.

Why do people so often use metaphorical expressions when literal paraphrases are readily available? This study focuses on a comparison of metaphorical statements involving the source domain of taste (e.g., "She looked at him sweetly") and their literal paraphrases (e.g., "She looked at him kindly"). Metaphorical and literal sentences differed only in one word and were normed for length, familiarity, imageability, emotional valence, and arousal. Our findings indicate that conventional metaphorical expressions are more emotionally evocative than literal expressions, as the amygdala and the anterior portion of the hippocampus were more active in the metaphorical sentences. They also support the idea that even conventional metaphors can be grounded in sensorimotor and perceptual representations in that primary and secondary gustatory areas (lateral OFC, frontal operculum, anterior insula) were more active as well. A comparison of the individual words that distinguished the metaphorical and literal sentences revealed greater activation in the lateral OFC and the frontal operculum for the taste-related words, supporting the claim that these areas are relevant to taste.

Prediction plays a key role in language development as well as processing.

Although the target article emphasizes the important role of prediction in language use, prediction may well also play a key role in the initial formation of linguistic representations, that is, in language development. We outline the role of prediction in three relevant language-learning domains: transitional probabilities, statistical preemption, and construction learning.

Substantive learning bias or an effect of familiarity? Comment on Culbertson, Smolensky, and Legendre (2012).

Typologists have long observed that there are certain distributional patterns that are not evenly distributed among the world's languages. This discussion note revisits a recent experimental investigation of one such intriguing case, so-called "universal 18", by Culbertson, Smolensky, and Legendre (2012). The authors find that adult learners are less likely to generalize an artificial grammar that involves the word order combination Adjective-before-Noun and Noun-before-Numeral, and they attribute this to two factors: (1) a domain-general preference for consistency-i.e., a preference for either N before Adj/Num, or N after, and (2) a domain-specific unlearned universal bias against Adj-N+N-Num order. An alternative explanation for the second factor is that it involves a transfer effect from either Spanish-type languages or from English. The case for possible transfer from English is based on the fact that adjectives regularly occur after the nouns they modify in several English constructions, whereas numerals only quantify the nouns they follow in one construction that occurs extremely infrequently.