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The non-fluent/agrammatic variant of primary progressive aphasia (nfvPPA) is a neurodegenerative syndrome primarily defined by the presence of apraxia of speech (AoS) and/or expressive agrammatism. In addition, many patients exhibit dysarthria and/or receptive agrammatism. This leads to substantial phenotypic variation within the speech-language domain across individuals and time, in terms of both the specific combination of symptoms as well as their severity. How to resolve such phenotypic heterogeneity in nfvPPA is a matter of debate. 'Splitting' views propose separate clinical entities: 'primary progressive apraxia of speech' when AoS occurs in the absence of expressive agrammatism, 'progressive agrammatic aphasia' (PAA) in the opposite case, and 'AOS + PAA' when mixed motor speech and language symptoms are clearly present. While therapeutic interventions typically vary depending on the predominant symptom (e.g. AoS versus expressive agrammatism), the existence of behavioural, anatomical and pathological overlap across these phenotypes argues against drawing such clear-cut boundaries. In the current study, we contribute to this debate by mapping behaviour to brain in a large, prospective cohort of well characterized patients with nfvPPA (n = 104). We sought to advance scientific understanding of nfvPPA and the neural basis of speech-language by uncovering where in the brain the degree of MRI-based atrophy is associated with inter-patient variability in the presence and severity of AoS, dysarthria, expressive agrammatism or receptive agrammatism. Our cross-sectional examination of brain-behaviour relationships revealed three main observations. First, we found that the neural correlates of AoS and expressive agrammatism in nfvPPA lie side by side in the left posterior inferior frontal lobe, explaining their behavioural dissociation/association in previous reports. Second, we identified a 'left-right' and 'ventral-dorsal' neuroanatomical distinction between AoS versus dysarthria, highlighting (i) that dysarthria, but not AoS, is significantly influenced by tissue loss in right-hemisphere motor-speech regions; and (ii) that, within the left hemisphere, dysarthria and AoS map onto dorsally versus ventrally located motor-speech regions, respectively. Third, we confirmed that, within the large-scale grammar network, left frontal tissue loss is preferentially involved in expressive agrammatism and left temporal tissue loss in receptive agrammatism. Our findings thus contribute to define the function and location of the epicentres within the large-scale neural networks vulnerable to neurodegenerative changes in nfvPPA. We propose that nfvPPA be redefined as an umbrella term subsuming a spectrum of speech and/or language phenotypes that are closely linked by the underlying neuroanatomy and neuropathology.

In this study, we investigated whether different morphosyntactic features, i.e. number and gender, play a role during the adult online comprehension of subject relative clauses (SRC) and object relative clauses (ORC), in Italian. This study was inspired by developmental studies showing that children struggle with ORC compared to SRC; yet, ORC comprehension improves if the head and the subject of the RC mismatch in relevant morphosyntactic features (e.g. number but not gender in Italian, based on the featural Relativized Minimality principle, fRM). We found that Italian adults read ORC more slowly than SRC verbs; moreover, ORC verbs were read faster in the head-subject number mismatch condition, while there was no facilitation in the head-subject gender mismatch condition, in line with developmental studies and fRM. We conclude that online parsing is feature-sensitive, that features are not all equally “relevant”, and that current models should be refined to account for these differences.

The ability to think about nonpresent time is a crucial aspect of human cognition. Both the past and future imply a temporal displacement of an event outside the "now." They also intrinsically differ: The past refers to inalterable events; the future to alterable events, to possible worlds. Are the past and future processed similarly or differently? In this study, we addressed this question by investigating how Spanish speakers process past/future time reference violations during sentence processing, while recording eye movements. We also investigated the role of verbs (in isolation; within sentences) and adverbs (deictic; nondeictic) during time processing. Existing accounts propose that past processing, which requires a link to discourse, is more complex than future processing, which-like the present-is locally bound. Our findings show that past and future processing differs, especially at early stages of verb processing, but this difference is not limited to the presence/absence of discourse linking. We found earlier mismatch effects for past compared to future time reference in incongruous sentences, in line with previous studies. Interestingly, it took longer to categorize the past than the future tense when verbs were presented in isolation. However, it took longer to categorize the future than the past when verbs were presented in congruous sentences, arguably because the future implies alterable worlds. Finally, temporal adverbs were found to play an important role in reinspection and reanalysis triggered by the presence of undefined time frames (nondeictic adverbs) or incongruences (mismatching verbs). (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Language processing is predictive in nature. But how dopeople balance multiple competing options as they predictupcoming meanings? Here, we investigated whether readersgenerate graded predictions about grammatical gender ofnouns. Sentence contexts were manipulated so that theystrongly biased people's expectations towards two or morenouns that had the same grammatical gender (single biascondition), or they biased multiple genders from differentgrammatical classes (multiple bias condition). Ourexpectation was that unexpected articles should lead toelevated reading times (RTs) in the single-bias conditionwhen probabilistic expectations towards a particular genderare violated. Indeed, the results showed greater sensitivityamong language users towards unexpected articles in thesingle-bias condition, however, RTs on unexpected gender-marked articles were facilitated, and not slowed. Our dataconfirm that difficulty in sentence processing is modulatedby uncertainty about predicted information, and suggest thatreaders make graded predictions about grammatical gender.

Bilinguals learn to resolve conflict between their two languages and that skill has been hypothesized to create long-term adaptive changes in cognitive functioning. Yet, little is known about how bilinguals recruit cognitive control to enable efficient use of one of their languages, especially in the less skilled and more effortful second language (L2). Here we examined how real-time cognitive control engagement influences L2 sentence comprehension (i.e., conflict adaptation). We tested a group of English monolinguals and a group of L2 English speakers using a recently-developed cross-task adaptation paradigm. Stroop sequences were pseudo-randomly interleaved with a visual-world paradigm in which participants were asked to carry out spoken instructions that were either syntactically ambiguous or unambiguous. Consistent with previous research, eye-movement results showed that Stroop-related conflict improved the ability to engage correct-goal interpretations, and disengage incorrect-goal interpretations, during ambiguous instructions. Such cognitive-to-language modulations were similar in both groups, but only in the engagement piece. In the disengagement portion, the modulation emerged earlier in bilinguals than in monolinguals, suggesting group differences in attentional disengagement following cognitive control recruitment. Additionally, incorrect-goal eye-movements were modulated by individual differences in working memory, although differently for each group, suggesting an involvement of both language-specific and domain-general resources.

This study presents a web-based sentence comprehension test aimed at identifying high school students who are at risk for a language delay. By assessing linguistic skills on a sample of high school students with Italian as an L2 and their monolingual peers, attending a vocational school, we were able to identify a subgroup of L2 students with consistent difficulties in sentence comprehension, though their reading skills were within the average range. The same subgroup revealed to experience a lack of support within the school context, suggesting that poor L2 skills might be a critical variable to consider in order to identify students at risk for school exclusion. Regarding the test, accuracy to the on-line sentence comprehension task was significantly predicted by reading abilities and vocabulary skills, thus indicating that this test might represent a rapid but efficient way to assess linguistic abilities at school. We recommend that establishing a valid and practical procedure for the evaluation of linguistic skills in bilingual students who struggle with their L2 is the first step toward promoting social inclusion in the multilingual classroom, in order to increase their ability to actively participate in school and social activities.

The present study examined the processing of temporal adverbial phrases such as "last week," which must agree in temporal features with the verb they modify. We investigated readers' sensitivity to this feature match or mismatch in two eye-tracking studies. The main aim of this study was to expand the range of concord phenomena which have been investigated in real-time processing in order to understand how linguistic dependencies are formed during sentence comprehension (Felser et al., 2017). Under a cue-based perspective, linguistic dependency formation relies on an associative cue-based retrieval mechanism (Lewis et al., 2006; McElree, 2006), but how such a mechanism is deployed over diverse linguistic dependencies remains a matter of debate. Are all linguistic features candidate cues that guide retrieval? Are all cues given similar weight? Are different cues differently weighted based on the dependency being processed? To address these questions, we implemented a mismatch paradigm (Sturt, 2003) adapted for temporal concord dependencies. This paradigm tested whether readers were sensitive to a temporal agreement between a temporal adverb like last week and a linearly distant, but structurally accessible verb, as well as a linearly proximate but structurally inaccessible verb. We found clear evidence that readers were sensitive to feature match between the adverb and the linearly distant, structurally accessible verb. We found no clear evidence on whether feature match with the inaccessible verb impacted the processing of a temporal adverb. Our results suggest syntactic positional information plays an important role during the processing of the temporal concord relation.

In everyday communication, speakers make errors and produce language in a noisy environment. Recent work suggests that comprehenders possess cognitive mechanisms for dealing with noise in the linguistic signal: a noisy-channel model. A key parameter of these models is the noise model: the comprehender's implicit model of how noise affects utterances before they are perceived. Here we examine this noise model in detail, asking whether comprehension behavior reflects a noise model that is adapted to context. We asked readers to correct sentences if they noticed errors, and manipulated context by including exposure sentences containing obvious deletions (A bystander was rescued by the fireman in the nick time.), insertions, exchanges, mixed errors, or no errors. On test sentences (The bat swung the player.), participants' corrections differed depending on the exposure condition. The results demonstrate that participants model specific types of errors and make inferences about the intentions of the speaker accordingly.

We present a case-study demonstrating the usefulness ofBayesian hierarchical mixture modelling for investigating cog-nitive processes. In sentence comprehension, it is widely as-sumed that the distance between linguistic co-dependents af-fects the latency of dependency resolution: the longer thedistance, the longer the retrieval time (the distance-based ac-count). An alternative theory, direct-access, assumes that re-trieval times are a mixture of two distributions: one distribu-tion represents successful retrievals (these are independent ofdependency distance) and the other represents an initial failureto retrieve the correct dependent, followed by a reanalysis thatleads to successful retrieval. We implement both models asBayesian hierarchical models and show that the direct-accessmodel explains Chinese relative clause reading time data betterthan the distance account.

Using real-time eye-movement measures, we asked how afantastical discourse context competes with stored representationsof semantic and world knowledge to influence children's andadults' moment-by-moment interpretation of a story. Seven-year-olds were less effective at bypassing stored semantic and worldknowledge during real-time interpretation than adults.Nevertheless, an effect of discourse context on comprehension wasstill apparent.

Background: Effects of word frequency on language comprehension and production are pervasive in speakers with and without aphasia. Frequency effects at the sentence level are likewise pervasive in neurotypical speakers, but have received relatively little attention in the aphasia literature. When discussed, frequency-based explanations have typically been dismissed as explanations of sentence-level deficits. Usage-based approaches to understanding the accessibility of clause and phrase structures are not widely used in aphasiology, in spite of their psycholinguistic plausibility. Aims: One aim is to show that evidence in support of probabilistic models of aphasic sentence comprehension and production has been available for a long time, but has lacked visibility. Our second aim is to respond to one of the few papers [Bastiaanse, R. Bouma, G., & Post, W. (2009). Linguistic complexity and frequency in agrammatic speech production. Brain and Language, 109, 18–28.] that directly challenge frequency-based explanations. The third aim is to discuss some of the reasons why probabilistic models in aphasia have been far slower to gain traction in aphasiology than in psycholinguistic research on neurotypical speakers. Methods & Procedures: We review available studies of probabilistic sentence-level deficits in aphasia. We revisit and reanalyse some of the data presented in Bastiaanse et al. [Bastiaanse, R. Bouma, G., & Post, W. (2009). Linguistic complexity and frequency in agrammatic speech production. Brain and Language, 109, 18–28.] Outcomes & Results: We find the data compatible in Bastiaanse et al. to be consistent with the predictions of a usage-based account. We argue that the paucity of studies of probabilistic and other usage-based effects in aphasia has its roots in the dichotomy drawn between “algorithmic” versus “heuristic” factors in sentence processing. We argue that this dichotomy is artificial. “Heuristics” are part and parcel of sentence processing in all speakers. Conclusions: The effect of usage—that is, of the individual’s past linguistic experience—is evident in the language of people with aphasia, as it is in speakers generally. We argue that usage-based approaches are promising because of the gradient and “noisy, but not random” nature of language processing in aphasia, and that they are natural companions to life-participation approaches to aphasia rehabilitation.

The let alone construction (John can't run a mile, let alone a marathon) differs from standard coordination structures (with and or but) by requiring ellipsis of the second conjunct--for example, a marathon is the remnant of an elided clause [[see text] a marathon]. In support of an ellipsis account, a corpus study of British and American English finds that let alone exhibits a Locality bias, as the second conjunct preferentially contrasts with the nearest lexical item of the same syntactic type. Two self-paced reading studies show that the Locality bias is active during online processing, but must be reconciled with indicators of semantic contrast and discourse information. Further, a sentence-rating study shows that the Locality bias interacts with a Finality bias that favours placing the let alone phrase at the end of a clause, which sometimes necessitates a nonlocal contrast. Together, the results show how a general bias in ellipsis for local contrasts is affected by discourse demands, such as the need for scalar contrast imposed by let alone, thereby offering a window into how possibly divergent syntactic and discourse constraints impact sentence processing.

Younger adults use both semantic and phonological cues toquickly and efficiently localize the referent during sentencecomprehension. While some behavioral studies suggest thatolder adults use contextual information even more stronglythan younger adults, ERP studies have shown that thispopulation, as a group, is less apt at using contextual semanticcues to predict upcoming words. The current study extendsthe investigation of contextual cue processing in auditorysentence comprehension beyond semantic cue processing, bycomparing younger and older adults in their ability to usephonological cues in indefinite articles (a/an) to localize thereferent in an eye-tracking visual world paradigm. Our resultssuggest that both age groups use such phonologicalinformation for referent localization, but with differenttimelines: younger adults use the cues to anticipate anupcoming word, whereas older adults show delayed cueprocessing after the target word has been spoken. Togetherwith findings from semantic context processing, these resultssupport a model of sentence comprehension in which the useof contextual cues continues with aging, but is no longer asefficient as in the young system for anticipatory wordretrieval.

The N400 component of the event-related brain potential iswidely used in research on language and semantic memory,but the cognitive functions underlying N400 amplitudes arestill unclear and actively debated. Recent simulations with aneural network model of word meaning suggest that N400amplitudes might reflect implicit semantic prediction error.Here, we extend these simulations to sentencecomprehension, using a neural network model of sentenceprocessing to simulate a number of N400 effects obtained inempirical research. In the model, sequentially incoming wordsupdate a representation capturing probabilities of elements ofsentence meaning, not only reflecting the constituentspresented so far, but also the model’s best guess at all featuresof the sentence meaning based on the statistical regularities inthe model’s environment internalized in its connectionweights. Simulating influences of semantic congruity, clozeprobability, a word’s position in the sentence, reversalanomalies, semantic and associative priming, categoricallyrelated incongruities, lexical frequency, repetition, andinteractions between repetition and semantic congruity, wefound that the update of the predictive representation ofsentence meaning consistently patterned with N400amplitudes. These results are in line with the idea that N400amplitudes reflect semantic surprise, defined as the change inthe probability distribution over semantic features in anintegrated representation of meaning occasioned by the arrivalof each successive constituent of a sentence.

Comprehenders predict upcoming speech and text on the basis of linguistic input. How many predictions do comprehenders make for an upcoming word? If a listener strongly expects to hear the word "sock", is the word "shirt" partially expected as well, is it actively inhibited, or is it ignored? The present research addressed these questions by measuring the "downstream" effects of prediction on the processing of subsequently presented stimuli using the cumulative semantic interference paradigm. In three experiments, subjects named pictures (sock) that were presented either in isolation or after strongly constraining sentence frames ("After doing his laundry, Mark always seemed to be missing one…"). Naming sock slowed the subsequent naming of the picture shirt - the standard cumulative semantic interference effect. However, although picture naming was much faster after sentence frames, the interference effect was not modulated by the context (bare vs. sentence) in which either picture was presented. According to the only model of cumulative semantic interference that can account for such a pattern of data, this indicates that comprehenders pre-activated and maintained the pre-activation of best sentence completions (sock) but did not maintain the pre-activation of less likely completions (shirt). Thus, comprehenders predicted only the most probable completion for each sentence.

Previous visual world eye-tracking studies have shown thatwhen a sentential verb can refer (via tense information on theverb and on a following time adverb) to either a recent anda future action event performed by an actor, people inspectedthe target of the recent event more often than the (different)target of the future event. This ’recent event preference’ replicatedeven when the frequency of future events within the experimentgreatly exceeded the frequency of recent events (e.g.,75% vs 25%). The recent event preference may arise becausethe past action is situation-immediate and thus more relevant atthe particular point in time when the sentence is processed (atthat point participants have seen the past action performed andwill not see the future action until after the sentence). If thesituation-immediate relevance of a cue is responsible for therecent event preference, then we should be able to “overwrite”the effect of the recent action with another situation-immediatecue. Accordingly, two current eye-tracking experiments pittedthe recent event preference against a situation-immediate cue,the shift in the actor’s gaze to the target object. Given that interlocutors’gaze has been shown to be a powerful cue in guidinglisteners’ attention to objects in the visual context, we hypothesizedthat the actor’s gaze to the future target should rapidlyguide a listener’s attention to it. Analyses revealed indeed thatlisteners’ visual attention was rapidly guided to the target bythe actor’s gaze; crucially the gaze cue was particularly helpfulin guiding looks to the future target. Importantly, however, westill replicated the overall preference to look at the recent targetregardless of tense and gaze; and even for future gaze conditions,the preference was not immediately reversed, suggestingit is surprisingly robust in competition with a situation-specificfuture-biasing cue.

Childhood socioeconomic status (SES) has a broad impacton cognitive development including nearly every aspect oflanguage ability. In infancy, lower SES is associated withdelays in real-time language processing skills, but it is notknown whether or how this relationship carries intoadulthood. We explore these questions by assessing thetimecourse of anticipatory sentence interpretation in avisual-world eye-tracking task in college-aged adults fromhigher and lower SES backgrounds. While there were onlysubtle SES-related timing differences in anticipation of asentence-final target noun, we found SES-related differencesin looks to competitor items on the screen. Particularly,individuals from higher SES backgrounds showed relativelymore looks to action-related competitors just prior to onsetof the target noun. These findings suggest that early SESinfluences the dynamics of lexical activation during sentenceprocessing even in adulthood and highlight the importanceof early lexical input and experience for adult language skill

Previous studies have shown that brain regions for mentalizing, including temporoparietal junction (TPJ) and medial prefrontal cortex (mPFC), are activated in understanding the nonliteral meaning of sentences. A different set of brain regions, including left inferior frontal gyrus (IFG), is activated for dealing with pragmatic incongruence. Here we demonstrate that individuals' cognitive empathic ability modulates the brain activity underlying the processing of pragmatic constraints during sentence comprehension. The lian … dou … construction in Chinese (similar to English even) normally describes an event of low expectedness; it also introduces a pragmatic scale against which the likelihood of an underspecified event can be inferred. By embedding neutral or highly likely events in the construction, we created underspecified and incongruent sentences and compared both with control sentences in which events of low expectedness were described. Imaging results showed that (i) left TPJ was activated for the underspecified sentences, and the activity in mPFC correlated with individuals' fantasizing ability and (ii) anterior cingulate cortex (ACC) was activated for the incongruent sentences, and the activity in bilateral IFG correlated with individuals' perspective taking ability. These findings suggest that brain activations in making pragmatic inference and in dealing with pragmatic failure are modulated by different components of cognitive empathy.

Two divided visual field priming experiments examined cerebral asymmetries for understanding metaphors varying in sentence constraint. Experiment 1 investigated ambiguous words (e.g., SWEET and BRIGHT) with literal and metaphoric meanings in ambiguous and unambiguous sentence contexts, while Experiment 2 involved standard metaphors (e.g., The drink you gave me was a meteor) with sententially consistent and inconsistent targets (i.e., POTENT vs COMET). Similar literal and metaphor priming effects were found in both visual fields across most experimental conditions. However, RH processes also maintained activation of sententially inconsistent literal meanings following metaphoric expressions. These results do not strongly support the RH as the preferred substrate for metaphor comprehension (e.g., ), and suggest that processes in both hemispheres can support metaphor comprehension, although not via identical mechanisms. The LH may utilize sentence constraint to select and integrate only contextually relevant literal and metaphoric meanings, whereas the RH may be less sensitive to sentence context and can maintain the activation of some alternative interpretations. This may be potentially useful in situations where an initial understanding must be revised.