Impaired Sentence Comprehension Research Articles

Atypical mixed logopenic and semantic progressive primary aphasia (PPA) in Arabic with white matter abnormalities

AbstractBackgroundThe concept of primary progressive aphasia (PPA) or Mesulam syndrome (Mesulam, 2014) is an isolated and progressive deterioration of language, usually due to progressive focal atrophy of the left perisylvian regions (of the dominant hemisphere). Four types of PPA have been already identified: Non‐fluent variant or Nfv‐PPA; Logopenic variant or Lv‐PPA; Semantic variant or Sv‐PPA and Mixed variant M‐PPA (Gorno‐Tempini et al., 2011; Mesulam et al., 2014).MethodWe report MH who displayed a Mixed‐variant of PPA (M‐PPA) in Arabic. Her daily activities were preserved. Neuroimaging using MRI coronal cut (FLAIR) showed a bi‐hippocampal atrophy, an increase in the sylvian valley and ventricular dilation; signs of cortical and subcortical vascular leukoencephalopathy. While the axial T2 cut showed a peri‐ventricular leukoencephalopathy. In FDG‐PET, there was a hypometabolism in the left anterior and the upper temporal gyrus. A neuropsychological battery was administered to the patient as well as a neurolinguistic assessment using an adapted and validated version of Moroccan Mini‐Linguistic State Examination (MLSE). It has been developed in English and Italian (Catricalà et al, 2017; Patel et al, 2020).ResultThe clinical profile of MH clearly showed an atypical overlap of neuropsychological, neurolinguistic and neuroradiological features which objectified a mixed variant of PPA predominantly logopenic and semantic with a slight syntactic impairment. These linguistic disturbances included some elements of Lv‐PPA (impaired sentence repetition and dysnomia) and some features of Sv‐PPA (dysnomia, impaired word comprehension, semantic association and sentence comprehension).ConclusionThe findings of this case study were mainly based on clinical and semiological criterias which are consistent with Mesulam’s descriptions (2014). It is possible that the presence of multi‐domain linguistic deficits may be linked eventually to a mixed underlying neuropathology which might be both neurodegenerative and vascular. This study is a call for a cross‐cultural neuropsychological, neuro‐anatomical and neurolinguistic characterization of PPA and Mixed‐PPA in non‐European languages

Language impairment in the genetic forms of behavioural variant frontotemporal dementia

BackgroundBehavioural variant fronto-temporal dementia (bvFTD) is characterised by a progressive change in personality in association with atrophy of the frontal and temporal lobes. Whilst language impairment has been described in people with bvFTD, little is currently known about the extent or type of linguistic difficulties that occur, particularly in the genetic forms.MethodsParticipants with genetic bvFTD along with healthy controls were recruited from the international multicentre Genetic FTD Initiative (GENFI). Linguistic symptoms were assessed using items from the Progressive Aphasia Severity Scale (PASS). Additionally, participants undertook the Boston Naming Test (BNT), modified Camel and Cactus Test (mCCT) and a category fluency test. Participants underwent a 3T volumetric T1-weighted MRI, with language network regional brain volumes measured and compared between the genetic groups and controls.Results76% of the genetic bvFTD cohort had impairment in at least one language symptom: 83% C9orf72, 80% MAPT and 56% GRN mutation carriers. All three genetic groups had significantly impaired functional communication, decreased fluency, and impaired sentence comprehension. C9orf72 mutation carriers also had significantly impaired articulation and word retrieval as well as dysgraphia whilst the MAPT mutation group also had impaired word retrieval and single word comprehension. All three groups had difficulties with naming, semantic knowledge and verbal fluency. Atrophy in key left perisylvian language regions differed between the groups, with generalised involvement in the C9orf72 group and more focal temporal and insula involvement in the other groups. Correlates of language symptoms and test scores also differed between the groups.ConclusionsLanguage deficits exist in a substantial proportion of people with familial bvFTD across all three genetic groups. Significant atrophy is seen in the dominant perisylvian language areas and correlates with language impairments within each of the genetic groups. Improved understanding of the language phenotype in the main genetic bvFTD subtypes will be helpful in future studies, particularly in clinical trials where accurate stratification and monitoring of disease progression is required.

Treatment of Underlying Forms: A Bayesian Meta-Analysis of the Effects of Treatment and Person-Related Variables on Treatment Response.

Purpose This meta-analysis synthesizes published studies using "treatment of underlying forms" (TUF) for sentence-level deficits in people with aphasia (PWA). The study aims were to examine group-level evidence for TUF efficacy, to characterize the effects of treatment-related variables (sentence structural family and complexity; treatment dose) in relation to the Complexity Account of Treatment Efficacy (CATE) hypothesis, and to examine the effects of person-level variables (aphasia severity, sentence comprehension impairment, and time postonset of aphasia) on TUF response. Method Data from 13 single-subject, multiple-baseline TUF studies, including 46 PWA, were analyzed. Bayesian generalized linear mixed-effects interrupted time series models were used to assess the effect of treatment-related variables on probe accuracy during baseline and treatment. The moderating influence of person-level variables on TUF response was also investigated. Results The results provide group-level evidence for TUF efficacy demonstrating increased probe accuracy during treatment compared with baseline phases. Greater amounts of TUF were associated with larger increases in accuracy, with greater gains for treated than untreated sentences. The findings revealed generalization effects for sentences that were of the same family but less complex than treated sentences. Aphasia severity may moderate TUF response, with people with milder aphasia demonstrating greater gains compared with people with more severe aphasia. Sentence comprehension performance did not moderate TUF response. Greater time postonset of aphasia was associated with smaller improvements for treated sentences but not for untreated sentences. Conclusions Our results provide generalizable group-level evidence of TUF efficacy. Treatment and generalization responses were consistent with the CATE hypothesis. Model results also identified person-level moderators of TUF (aphasia severity, time postonset of aphasia) and preliminary estimates of the effects of varying amounts of TUF for treated and untreated sentences. Taken together, these findings add to the TUF evidence and may guide future TUF treatment-candidate selection. Supplemental Material https://doi.org/10.23641/asha.16828630.

A Computational Evaluation of Two Models of Retrieval Processes in Sentence Processing in Aphasia.

Can sentence comprehension impairments in aphasia be explained by difficulties arising from dependency completion processes in parsing? Two distinct models of dependency completion difficulty are investigated, the Lewis and Vasishth (2005) activation-based model and the direct-access model (DA; McElree, 2000). These models' predictive performance is compared using data from individuals with aphasia (IWAs) and control participants. The data are from a self-paced listening task involving subject and object relative clauses. The relative predictive performance of the models is evaluated using k-fold cross-validation. For both IWAs and controls, the activation-based model furnishes a somewhat better quantitative fit to the data than the DA. Model comparisons using Bayes factors show that, assuming an activation-based model, intermittent deficiencies may be the best explanation for the cause of impairments in IWAs, although slowed syntax and lexical delayed access may also play a role. This is the first computational evaluation of different models of dependency completion using data from impaired and unimpaired individuals. This evaluation develops a systematic approach that can be used to quantitatively compare the predictions of competing models of language processing.

Common and distinct neural substrates of sentence production and comprehension

Functional neuroimaging and lesion-symptom mapping investigations implicate a left frontal–temporal–parietal network for sentence processing. The majority of studies have focused on sentence comprehension, with fewer in the domain of sentence production, which have not fully elucidated overlapping and/or unique brain structures associated with the two domains, particularly for sentences with noncanonical word order. Using voxel-based lesion symptom mapping (VLSM) we examined the relationship between lesions within the left hemisphere language network and both sentence comprehension and production of simple and complex syntactic structures in 76 participants with chronic stroke-induced aphasia. Results revealed shared regions across domains in the anterior and posterior superior temporal gyri (aSTG, pSTG), and the temporal pole (adjusted for verb production/comprehension). Additionally, comprehension was associated with lesions in the anterior and posterior middle temporal gyri (aMTG, pMTG), the MTG temporooccipital regions, SMG/AG, central and parietal operculum, and the insula. Subsequent VLSM analyses (production versus comprehension) revealed critical regions associated with each domain: anterior temporal lesions were associated with production; posterior temporo-parietal lesions were associated with comprehension, implicating important roles for regions within the ventral and dorsal stream processing routes, respectively. Processing of syntactically complex, noncanonical (adjusted for canonical), sentences was associated with damage to the pSTG across domains, with additional damage to the pMTG and IPL associated with impaired sentence comprehension, suggesting that the pSTG is crucial for computing noncanonical sentences across domains and that the pMTG, and IPL are necessary for re-analysis of thematic roles as required for resolution of long-distance dependencies. These findings converge with previous studies and extend our knowledge of the neural mechanisms of sentence comprehension to production, highlighting critical regions associated with both domains, and further address the mechanism engaged for syntactic computation, controlled for the contribution of verb processing.

Effects of prosody on the cognitive and neural resources supporting sentence comprehension: A behavioral and lesion-symptom mapping study

Non-canonical sentence comprehension impairments are well-documented in aphasia. Studies of neurotypical controls indicate that prosody can aid comprehension by facilitating attention towards critical pitch inflections and phrase boundaries. However, no studies have examined how prosody may engage specific cognitive and neural resources during non-canonical sentence comprehension in persons with left hemisphere damage. Experiment 1 examines the relationship between comprehension of non-canonical sentences spoken with typical and atypical prosody and several cognitive measures in 25 persons with chronic left hemisphere stroke and 20 matched controls. Experiment 2 explores the neural resources critical for non-canonical sentence comprehension with each prosody type using region-of-interest-based multiple regressions. Lower orienting attention abilities and greater inferior frontal and parietal damage predicted lower comprehension, but only for sentences with typical prosody. Our results suggest that typical sentence prosody may engage attention resources to support non-canonical sentence comprehension, and this relationship may be disrupted following left hemisphere stroke.

The effects of prosody on sentence comprehension: evidence from a neurotypical control group and seven cases of chronic stroke

ABSTRACTBoth prosody and sentence structure (e.g., canonical versus non-canonical) affect sentence comprehension. However, few previous studies have examined a possible interaction between prosody and sentence structure. In adult controls we found a significant interaction: typical sentence prosody, versus list prosody, facilitated comprehension of only some sentence structures. In seven stroke patients, impaired attentional control was related to impaired comprehension with sentence prosody but not list prosody; impaired working memory was related to impaired comprehension with list prosody, but not sentence prosody. Thus, non-canonical sentence comprehension impairments in stroke patients may be modulated by prosody, based on a patient’s cognitive abilities.

Clinical and neuroimaging investigations of language disturbance in frontotemporal dementia-motor neuron disease patients.

This study systematically investigated the neuropsychological profile of language disturbance in frontotemporal dementia-motor neuron disease (FTD-MND) using a data-driven approach. Neuroanatomical correlates of language profiles were also examined. Patients with FTD-MND (N = 26), pure motor neuron disease (N = 34), progressive non-fluent aphasia (N = 30), semantic dementia (N = 17), and controls (N = 31) underwent comprehensive language assessments. Clinical assessments were complemented with the Sydney Language Battery (SYDBAT), to assess semantic abilities, and the Test for Reception of Grammar (TROG), to assess syntactic comprehension. Two-step cluster analysis examined patterns of language impairment in FTD-MND and voxel-based morphometry investigated neuroanatomical differences between clusters. Almost all (88.5%) FTD-MND patients had language impairment, with anomia in 73.1% and impaired sentence comprehension in 56%. Cluster analysis revealed two main profiles of language impairment in FTD-MND; a mild mixed semantic and syntactic impairment (mild mixed subgroup) seen in 12 cases and a subgroup with more marked impairment particularly of syntactic comprehension (PNFA-like subgroup) seen in 7 cases. VBM revealed disproportionate atrophy of the caudate head and putamen bilaterally in the PNFA-like subgroup. In conclusion, language disturbances in FTD-MND are heterogeneous and more mixed than seen in FTD language phenotypes. Atrophy of the caudate and putamen was correlated with disproportionate impairment of syntactic comprehension. A pure semantic dementia like syndrome appears to be rare in FTD-MND.

Cortical and structural-connectivity damage correlated with impaired syntactic processing in aphasia.

Agrammatism in aphasia is not a homogeneous syndrome, but a characterization of a nonuniform set of language behaviors in which grammatical markers and complex syntactic structures are omitted, simplified, or misinterpreted. In a sample of 71 left-hemisphere stroke survivors, syntactic processing was quantified with the Northwestern Assessment of Verbs and Sentences (NAVS). Classification analyses were used to assess the relation between NAVS performance and morphosyntactically reduced speech in picture descriptions. Voxel-based and connectivity-based lesion-symptom mapping were applied to investigate neural correlates of impaired syntactic processing. Despite a nonrandom correspondence between NAVS performance and morphosyntactic production deficits, there was variation in individual patterns of syntactic processing. Morphosyntactically reduced production was predicted by lesions to left-hemisphere inferior frontal cortex. Impaired verb argument structure production was predicted by damage to left-hemisphere posterior superior temporal and angular gyrus, as well as to a ventral pathway between temporal and frontal cortex. Damage to this pathway was also predictive of impaired sentence comprehension and production, particularly of noncanonical sentences. Although agrammatic speech production is primarily predicted by lesions to inferior frontal cortex, other aspects of syntactic processing rely rather on regional integrity in temporoparietal cortex and the ventral stream.

Meta-analysis of Treatment of Underlying Forms: dosage-related and person-level predictors of acquisition and generalization response

Meta-analysis of Treatment of Underlying Forms: dosage-related and person-level predictors of acquisition and generalization response

Electrophysiology of prosodic and lexical-semantic processing during sentence comprehension in aphasia

Event-related potentials (ERPs) were used to examine how individuals with aphasia and a group of age-matched controls use prosody and themattic fit information in sentences containing temporary syntactic ambiguities. Two groups of individuals with aphasia were investigated; those demonstrating relatively good sentence comprehension whose primary language difficulty is anomia (Individuals with Anomic Aphasia (IWAA)), and those who demonstrate impaired sentence comprehension whose primary diagnosis is Broca's aphasia (Individuals with Broca's Aphasia (IWBA)). The stimuli had early closure syntactic structure and contained a temporary early closure (correct)/late closure (incorrect) syntactic ambiguity. The prosody was manipulated to either be congruent or incongruent, and the temporarily ambiguous NP was also manipulated to either be a plausible or an implausible continuation for the subordinate verb (e.g., "While the band played the song/the beer pleased all the customers."). It was hypothesized that an implausible NP in sentences with incongruent prosody may provide the parser with a plausibility cue that could be used to predict syntactic structure. The results revealed that incongruent prosody paired with a plausibility cue resulted in an N400-P600 complex at the implausible NP (the beer) in both the controls and the IWAAs, yet incongruent prosody without a plausibility cue resulted in an N400-P600 at the critical verb (pleased) only in healthy controls. IWBAs did not show evidence of N400 or P600 effects at the ambiguous NP or critical verb, although they did show evidence of a delayed N400 effect at the sentence-final word in sentences with incongruent prosody. These results suggest that IWAAs have difficulty integrating prosodic cues with underlying syntactic structure when lexical-semantic information is not available to aid their parse. IWBAs have difficulty integrating both prosodic and lexical-semantic cues with syntactic structure, likely due to a processing delay.

The relationship between short-term memory, conflict resolution, and sentence comprehension impairments in aphasia

ABSTRACTBackground: Sentence comprehension involves the integration of multiple linguistic representations. This integration can be especially challenging when different cues lead to conflicting interpretations. Short-term memory (STM) and conflict resolution are two processes that have been previously linked to sentence comprehension and could assist in integration. However, the relation of each process to comprehension independently of the other has not been fully clarified.Aims: We tested two patients with contrasting STM and conflict resolution profiles in different sentence comprehension tasks to evaluate the relationship between the three abilities.Methods & Procedures: Patients completed (a) six STM tasks that tested either span or updating; (b) two executive function tasks that tested conflict resolution; and (c) three tasks that evaluated sentence comprehension.Outcomes & Results: The patient with poorer STM and better conflict resolution had variable success in sentence comprehension that was contingent on memory load and the extent to which interpretation was supported by semantic knowledge. In contrast, the patient with good STM but slow conflict resolution demonstrated accurate comprehension across all tasks and conditions, and delayed reaction times for sentences containing conflict between cues.Conclusions: The results provide broad support for a link between STM and sentence comprehension. They suggest that inefficient conflict resolution might be associated with slowed down but not inaccurate comprehension of sentences when other abilities, including STM, are intact. We discuss the ways in which STM and conflict resolution may and may not assist sentence comprehension in individuals with aphasia.

Examining the language and behavioural profile in FTD and ALS-FTD

BackgroundA proportion of patients with behavioural variant frontotemporal dementia (bvFTD) develop amyotrophic lateral sclerosis (ALS). It is currently unknown whether the behavioural and cognitive syndrome in bvFTD with ALS (ALS-FTD)...

Sentence comprehension in Slovak-speaking patients with Alzheimer's disease.

According to some studies, sentence comprehension is diminished in Alzheimer's disease (AD) patients, but they differ on what underlies the sentence comprehension impairment. Sentence comprehension in AD patients has been studied mainly in the English language. It is less clear how patients with AD speaking a morphologically rich language with grammatical morphemes indicating case and through it even thematic roles process reversible sentences. To compare the comprehension of various syntactic constructions in Slovak-speaking AD patients and cognitively intact elderly people. We were concerned with the influence of the following aspects on sentence comprehension: its length, the order of thematic roles and the presence of a morphological cue placed on the first noun (or at the beginning of a sentence). We used our own Slovak test of sentence comprehension based on matching pictures to spoken sentences. These sentences contain transitive verbs and two nouns (person/animal), one functioning as a subject and the other as an object, which both can perform the action expressed by the verb. We assessed 62 healthy elderly people and two groups of AD patients. The first group consisted of 34 participants with a mild degree of AD and the other group of 43 participants with a moderate degree of AD. Statistical comparisons showed that the elderly controls were significantly better in the comprehension of simple active OVS (object-verb-subject word order) sentences and complex EO sentences (a centre-embedded relative clause with a relative pronoun substituting for an object) than patients with a mild degree of AD. In patients with a moderate degree of AD, comprehension of all tested sentence types was worse than in healthy elderly people. The results also indicated that even mild AD patients have more serious problems with processing sentences with non-canonical order of thematic roles regardless of a morphological cue at the beginning of a sentence. The results point to diminished sentence comprehension in patients with AD. In the group of mild AD patients, the order of thematic roles played a significant role in their sentence comprehension. Even though the grammatical morphemes clearly code the functions of words in the Slovak language, mild AD patients do not process them in sentences with a non-canonical order of thematic roles at the same level as the healthy controls. Patients with moderate AD have significant problems even with the comprehension of sentences with a canonical order of thematic roles. These difficulties seem to be a consequence of insufficient resources for language processing.

"A lady of few words": Review of literature and report of a case of progressive nonfluent aphasia type of frontotemporal dementia

Frontotemporal dementia (FTD) is a clinically and pathologically heterogeneous syndrome. It can be classified into three clinical syndromes depending on the early and predominant symptoms: A behavioral variant FTD and two language variants namely, semantic dementia, and progressive nonfluent aphasia (PNFA) which are very rare and elude diagnosis. We report the case of an elderly homemaker who came to our institute with features of cognitive decline and behavioral problems with language deficits in the form of nonfluent speech, impaired vocabulary to three pairs of words, agrammatism, and impaired single sentence comprehension with corroborative magnetic resonance imaging findings. PNFA is a rare clinical variant of FTD and often underdiagnosed. It should be considered in elderly patients who apart from having cognitive decline, behavioral problems, and absent insight also develop limited vocabulary, especially using a set of nouns to express themselves. Speech therapy and behavioral therapy in the initial stages can be of utility.

The Wernicke conundrum and the anatomy of language comprehension in primary progressive aphasia

Wernicke's aphasia is characterized by severe word and sentence comprehension impairments. The location of the underlying lesion site, known as Wernicke's area, remains controversial. Questions related to this controversy were addressed in 72 patients with primary progressive aphasia who collectively displayed a wide spectrum of cortical atrophy sites and language impairment patterns. Clinico-anatomical correlations were explored at the individual and group levels. These analyses showed that neuronal loss in temporoparietal areas, traditionally included within Wernicke's area, leave single word comprehension intact and cause inconsistent impairments of sentence comprehension. The most severe sentence comprehension impairments were associated with a heterogeneous set of cortical atrophy sites variably encompassing temporoparietal components of Wernicke's area, Broca's area, and dorsal premotor cortex. Severe comprehension impairments for single words, on the other hand, were invariably associated with peak atrophy sites in the left temporal pole and adjacent anterior temporal cortex, a pattern of atrophy that left sentence comprehension intact. These results show that the neural substrates of word and sentence comprehension are dissociable and that a circumscribed cortical area equally critical for word and sentence comprehension is unlikely to exist anywhere in the cerebral cortex. Reports of combined word and sentence comprehension impairments in Wernicke's aphasia come almost exclusively from patients with cerebrovascular accidents where brain damage extends into subcortical white matter. The syndrome of Wernicke's aphasia is thus likely to reflect damage not only to the cerebral cortex but also to underlying axonal pathways, leading to strategic cortico-cortical disconnections within the language network. The results of this investigation further reinforce the conclusion that the left anterior temporal lobe, a region ignored by classic aphasiology, needs to be inserted into the language network with a critical role in the multisynaptic hierarchy underlying word comprehension and object naming.

Damage to Broca’s area OR the anterior temporal lobe is implicated in stroke-induced agrammatic comprehension: it depends on the task

Damage to Broca’s area OR the anterior temporal lobe is implicated in stroke-induced agrammatic comprehension: it depends on the task

Online Sentence Comprehension in PPA: Verb-Based Integration and Prediction

Online Sentence Comprehension in PPA: Verb-Based Integration and Prediction

Structural prediction in aphasia

Structural prediction in aphasia

What causes the processing advantage in the comprehension of German object relative clauses?

What causes the processing advantage in the comprehension of German object relative clauses?