Language Comprehension Task Research Articles

Flexibility in Embodied Language Understanding

Do people use sensori-motor cortices to understand language? Here we review neurocognitive studies of language comprehension in healthy adults and evaluate their possible contributions to theories of language in the brain. We start by sketching the minimal predictions that an embodied theory of language understanding makes for empirical research, and then survey studies that have been offered as evidence for embodied semantic representations. We explore four debated issues: first, does activation of sensori-motor cortices during action language understanding imply that action semantics relies on mirror neurons? Second, what is the evidence that activity in sensori-motor cortices plays a functional role in understanding language? Third, to what extent do responses in perceptual and motor areas depend on the linguistic and extra-linguistic context? And finally, can embodied theories accommodate language about abstract concepts? Based on the available evidence, we conclude that sensori-motor cortices are activated during a variety of language comprehension tasks, for both concrete and abstract language. Yet, this activity depends on the context in which perception and action words are encountered. Although modality-specific cortical activity is not a sine qua non of language processing even for language about perception and action, sensori-motor regions of the brain appear to make functional contributions to the construction of meaning, and should therefore be incorporated into models of the neurocognitive architecture of language.

Theory of mind and language comprehension in schizophrenia: Poor mindreading affects figurative language comprehension beyond intelligence deficits

Patients suffering from schizophrenia have been found to be impaired in their pragmatic abilities in the comprehension of figurative language (e.g., metaphors, ironies, proverbs). Impairments in theory of mind (ToM; that is, the ability to attribute/infer mental states) have been proposed to be underlying high level language understanding. Even though ToM has been shown to be defective in schizophrenia, there is little information about the pattern of relations between ToM and language comprehension (LC) abilities. Our aim in this study is to explore how deficits in ToM concern the LC capacity in schizophrenia when general intelligence is controlled for. A total of 22 Spanish-speaking inpatients and 22 healthy controls matched in age, sex, education and language dominance were assessed using 3 ToM tasks and 6 LC tasks (covering lexical, syntactic, and semantic–pragmatic language processing levels) in order to establish to what extent ToM gets associated with LC abilities. Correlational analysis showed a connection between impairments in ToM and difficulties in LC. A discriminant function analysis showed that the variables that best discriminate between patients and controls are those corresponding to ToM-critical items and figurative LC tasks. Impairments in ToM seem to be mainly associated to LC in the semantic–pragmatic processing level and this association appears to be genuine, non dependent on IQ. In schizophrenia, mindreading impairments contribute negatively to the process of understanding figurative meanings beyond the presence of an impoverished intelligence.

Cognate effects in bilingual language comprehension tasks

We examined cognate effects when late fluent Spanish/English bilingual speakers undergoing event-related potential recordings performed two tasks on word pairs. In an association decision task, participants decided whether or not pairs of Spanish words were related in meaning. In a translation decision task, they reported whether English target words were correct translations of Spanish primes. In both the tasks, word primes were either cognates or noncognates. In the translation decision task, faster and more accurate responses were associated with reduced N400 amplitudes in word pairs featuring a cognate. However, cognates did not modulate performance or event-related potentials in the association decision task. The results suggest that language coactivation in bilingual speakers is modulated by cognitive context.

Distinguishing clinical depression from early Alzheimer's disease in elderly people: Can narrative analysis help?

Background: Differentiating the reversible cognitive symptoms associated with depression (DEP) from the irreversible dementia associated with early or mild Alzheimer's disease (AD) has proven to be challenging, particularly in elderly individuals. Most previous studies have focused on contrasting the cognitive profiles associated with these disorders, often yielding unreliable clinical differences. Although a limited set of studies have identified significant differences between DEP and early AD groups on both basic and high-level language production and comprehension tasks, none has included spoken discourse measures, and several limitations within these language studies indicate that further research is warranted. Aims: This study examined whether depression is associated with a distinct pattern of discourse changes, and thus whether discourse analyses may help discriminate elderly individuals with DEP from those in the early stages of AD. Methods & Procedures: Groups of elderly participants with DEP, mild AD, or no psychiatric or neurological diagnosis, who were matched for age and education level, completed a spoken narrative task and general cognition and high-level language tests. Quantitative, syntactic, and informativeness aspects of the discourse samples were analysed. Outcomes & Results: Significant group differences were observed on the informativeness discourse measures, with AD participants producing less-informative samples than DEP and control participants. DEP and control groups did not significantly differ on any discourse variable. Conclusions: Including discourse sampling and analyses, with a focus on informativeness, into comprehensive assessment protocols may lead to more accurate discrimination of DEP and early AD in the elderly.

Behavioral and Neurophysiologic Response to Therapy for Chronic Aphasia

Breier JI, Juranek J, Maher LM, Schmadeke S, Men D, Papanicolaou AC. Behavioral and neurophysiologic response to therapy for chronic aphasia. Objective To characterize the relationship between neurophysiologic changes in the brain and behavioral response to constraint-induced language therapy (CILT) by using magnetoencephalography (MEG). Design Case series. Setting Medical school. Participants Patients (N=23) with chronic aphasia after first-time unilateral stroke in the left hemisphere. Interventions Constraint-induced language therapy administered for 3 hours 4 times per week for 3 weeks. Language testing and functional imaging during a language comprehension task using MEG before, immediately after, and 3 months after CILT with a subgroup of patients undergoing additional MEG scanning and language testing 3 weeks before CILT. Main Outcome Measures The percent of correct information units and the number of late dipoles normalized to total activation. Results Three patterns of behavioral and neurophysiologic response to CILT were identified. Patients with significant improvement in language immediately after CILT who lost these gains at follow-up had greater right hemisphere activation than other patients at all MEG scanning sessions. Patients with significant improvement in language immediately after CILT who maintained these gains at follow-up exhibited an increase in left temporal activation after CILT, whereas patients who did not exhibit significant improvement in language after CILT exhibited comparably greater activation in left parietal areas. Conclusions Results suggest that although the right hemisphere may support recovery of language function in response to therapy, this recovery may not be stable, and some participation of perilesional areas of the left hemisphere may be necessary for a stable behavioral response.

A case for conflict across multiple domains: Memory and language impairments following damage to ventrolateral prefrontal cortex

Patients with focal lesions to the left inferior frontal gyrus (LIFG; BA 44/45) exhibit difficulty with language production and comprehension tasks, although the nature of their impairments has been somewhat difficult to characterize. No reported cases suggest that these patients are Broca's aphasics in the classic agrammatic sense. Recent case studies, however, do reveal a consistent pattern of deficit regarding their general cognitive processes: They are reliably impaired on tasks in which conflicting representations must be resolved by implementing top-down cognitive control (e.g., Stroop; memory tasks involving proactive interference). In the present study, we ask whether the language production and comprehension impairments displayed by a patient with circumscribed LIFG damage can best be understood within a general conflict resolution deficit account. We focus on one patient in particular—patient I.G.—and discuss the implications for language processing abilities as a consequence of a general cognitive control disorder. We compared I.G. and other frontal patients to age-matched control participants across four experiments. Experiment 1 tested participants' general conflict resolution abilities within a modified working memory paradigm in an attempt to replicate prior case study findings. We then tested language production abilities on tasks of picture naming (Experiment 2) and verbal fluency (Experiment 3), tasks that generated conflict at the semantic and/or conceptual levels. Experiment 4 tested participants' sentence processing and comprehension abilities using both online (eye movement) and offline measures. In this task, participants carried out spoken instructions containing a syntactic ambiguity, in which early interpretation commitments had to be overridden in order to recover an alternative, intended analysis of sentence meaning. Comparisons of I.G.'s performance with frontal and healthy control participants supported the following claim: I.G. suffers from a general conflict resolution impairment, which affects his ability to produce and comprehend language under specific conditions—namely, when semantic, conceptual, and/or syntactic representations compete and must be resolved.

Lévy-like diffusion in eye movements during spoken-language comprehension

This study explores the diffusive properties of human eye movements during a language comprehension task. In this task, adults are given auditory instructions to locate named objects on a computer screen. Although it has been convention to model visual search as standard Brownian diffusion, we find evidence that eye movements are hyperdiffusive. Specifically, we use comparisons of maximum-likelihood fit as well as standard deviation analysis and diffusion entropy analysis to show that visual search during language comprehension exhibits Lévy-like rather than Gaussian diffusion.

Speed of Language Comprehension is Impaired in ADHD

Objective: Children with ADHD have an increased risk of poor academic performance. It is important to identify cognitive processes that may be related to this academic failure. In Western schooling systems, especially language processing skills may be of relevance. The present study, therefore, compares the ability to comprehend complex sentences of individuals with and without ADHD. Method: Fifteen children (aged 8-11) and 15 adolescents (aged 12-16) with ADHD combined subtype are matched for age, gender, and parental level of education to 30 control subjects. Language comprehension is measured using the neuropsychological procedure proposed by Luria and an adapted version of the Token Test. Results: Compared with the control group, children and adolescents with ADHD perform significantly slower on language comprehension tasks. Differences in accuracy are limited. No interaction between age and ADHD is found. Conclusions: Children and adolescents with ADHD are slower and less efficient than matched control subjects with regard to complex sentence comprehension. (J. of Att. Dis. 2010; 13(4) 374-385)

Functional deficit in the medial prefrontal cortex during a language comprehension task in patients with schizophrenia

Objective We and others have observed that patients with schizophrenia commonly presented a reduced left recruitment in language semantic brain regions. However, most studies include patients with leftward and rightward lateralizations for language. We investigated whether a cohort comprised purely of patients with typical lateralization (leftward) presented a reduced left recruitment in semantic regions during a language comprehension task. The goal was to reduce the inter-subject variability and thus improve the resolution for studying functional abnormalities in the language network. Methods Twenty-three patients with schizophrenia (DSM-IV) were matched with healthy subjects in age, sex, level of education and handedness. All patients exhibited leftward lateralization for language. Functional MRI was performed as subjects listened to a story comprising characters and social interactions. Functional MRI signal variations were analyzed individually and compared among groups. Results Although no differences were observed in the recruitment of the semantic language network, patients with schizophrenia presented significantly lower signal variations compared to controls in the medial part of the left superior frontal gyrus (MF1) ( x = − 6, y = 58, z = 20; Z score = 5.6; p < 0.001 uncorrected). This region corresponded to the Theory of Mind (ToM) network. Only 5 of the 23 patients (21.7%) and 21 of the 23 (91.3%) control subjects demonstrated a positive signal variation in this area. Conclusions A left functional deficit was observed in a core region of the ToM network in patients with schizophrenia and typical lateralizations for language. This functional defect could represent a neural basis for impaired social interaction and communication in patients with schizophrenia.

Association and not semantic relationships elicit the N400 effect: Electrophysiological evidence from an explicit language comprehension task

Language comprehension studies have identified the N400, an event-related potential (ERP) correlate of the processing of meaning, modulation of which is typically assumed to reflect the activation of semantic information. However, N400 studies of conscious language processing have not clearly distinguished between meaning derived from a semantic relationship and meaning extracted through association. We independently manipulated the presence of associative and semantic relationships while examining the N400 effect. Participants were asked to read and remember visually presented word pairs that shared an association (traffic-jam), an association+semantic relationship (lemon-orange), a semantic relationship alone (cereal-bread), or were unrelated (beard-tower). Modulation of the N400 (relative to unrelated word pairs) was observed for association and association+semantic word pairs but not for those that only shared a semantic relationship.

Changes in Language-specific Brain Activation after Therapy for Aphasia using Magnetoencephalography: A Case Study

A patient with chronic aphasia underwent functional imaging during a language comprehension task using magnetoencephalography (MEG) before and after constraint induced language therapy (CILT). In the pre- and immediate post-treatment (TX) scans MEG activity sources were observed within right hemisphere only, and were located in areas homotopic to left hemisphere language areas. There was a significant increase in activation in these areas between the two sessions. This change was not observed in an age-matched patient with chronic aphasia who underwent sequential language testing and MEG scanning across a similar time period without being administered therapy. In the 3-month post-TX scan bilateral activation was observed, including significant activation within the left temporal lobe. The changes in the spatial parameters of the maps of receptive language function after therapy were accompanied by improvement in language function. Results provide support, in the same individual, for a role for both hemispheres in recovery of language function after therapy for chronic aphasia.

Silent and continuous fMRI scanning differentially modulate activation in an auditory language comprehension task

Sparse temporal acquisition schemes have been adopted to investigate the neural correlates of human audition using blood-oxygen-level dependent (BOLD) based functional magnetic resonance imaging (fMRI) devoid of ambient confounding acoustic scanner noise. These schemes have previously been extended to clustered-sparse temporal acquisition designs which record several subsequent BOLD contrast images in rapid succession in order to enhance temporal sampling efficiency. In the present study we demonstrate that an event-related task design can effectively be combined with a clustered temporal acquisition technique in an auditory language comprehension task. The same fifteen volunteers performed two separate auditory runs which either applied customary fMRI acquisition (CA) composed of continuous scanner noise or "silent" fMRI built on a clustered temporal acquisition (CTA) protocol. In accord with our hypothesis, the CTA scheme relative to the CA protocol is accompanied by significantly stronger functional responses along the entire superior temporal plane. By contrast, the bilateral insulae engage more strongly during continuous scanning. A post-hoc region-of-interest analysis reveals cortical activation in subportions of the supratemporal plane which varies as a function of acquisition protocol. The middle part of the supratemporal plane shows a rightward asymmetry only for the CTA scheme while the posterior supratemporal plane exposes a significantly stronger leftward asymmetry during the CTA. Our findings implicate that silent fMRI is advantageous when it comes to the exploration of auditory and speech functions residing in the supratemporal plane.

Neurobehavioral Characteristics of Children with Fetal Alcohol Spectrum Disorders in Communities from Italy: Preliminary Results

There has been considerable effort expended on defining neurobehavioral characteristics of children with fetal alcohol spectrum disorders (FASD). Children with FASD display a range of cognitive deficits and behavioral problems. In this article, we report on the neurobehavioral characteristics of children with FASD in selected communities in Italy. It was expected that both inattentive and hyperactive/impulsive characteristics would discriminate children with FASD from controls and that the groups would also differ on intellectual functioning, language comprehension, and academic skills. Eighty-two children, 22 diagnosed with FASD and 60 control children, participated in this study. The children were administered tests of nonverbal reasoning, language comprehension, academic achievement, and behavior. On tests of nonverbal reasoning and language comprehension, the FASD group earned lower scores than did controls. Moreover, on a test of academic achievement the FASD group scored lower. When comparing these 2 groups on disruptive behavioral symptomatology, similar results were obtained, the FASD group showing greater attentional difficulties and hyperactivity/impulsivity behaviors and more overall behavioral problems. Stepwise logistic regression analysis showed that a model containing inattention and error scores on the language comprehension task correctly classified 85% of the participants. Compared with the control group, a significantly greater proportion of children with FASD met the Diagnostic and Statistical Manual of Mental Disorders-fourth edition (DSM-IV) criteria of ADD, inattentive type, as reported by teachers. In contrast, hyperactive symptoms among children with FASD were comparable with the control group. Teachers rated children with FASD as having more inattentive behaviors and as performing lower in academic skills than controls. The association between reported hyperactivity symptoms and achievement scores was nonsignificant for both language and math scores, suggesting that it is not the hyperactivity causing problems, but the child's inattention. This research indicates that a nonclinic-referred sample of Italian children with FASD display a profile of neurobehavioral functioning consistent with that reported by other researchers. Furthermore, the neurobehavioral characteristic most identified with children diagnosed with FASD was inattention followed by hyperactivity.

Hippocampal Formation Involvement in a Language‐activation Task in Patients with Mesial Temporal Lobe Epilepsy

The study aims to explore the contribution of the hippocampal formation to the retained language-comprehension network in patients with unilateral mesial temporal lobe epilepsy (TLE). We performed a functional magnetic resonance (MRI) study based on a language comprehension paradigm in 45 right-handed patients with unilateral mesial TLE and 35 healthy control subjects. Activations in the hippocampal formations in both hemispheres were analyzed for each subject as well as for groups of left TLE, right TLE, and controls. In sum, 82% of TLE patients displayed hippocampal activations. A significant difference in hippocampal activation between left and right TLE was found: Right TLE patients showed increased activity in the left hippocampal formation compared with left TLE patients. In contrast, patients with left TLE did not show increased activity in the right hippocampal formation compared with right TLE patients. In comparison with a healthy control group, right TLE patients activated the left hippocampal formation to a greater extent, whereas patients with left TLE did not activate the right hippocampal formation to a greater degree. These findings point to an increased involvement of the left hippocampal formation during a language-comprehension task in right TLE patients. In contrast, left TLE in right-handed patients seems not associated with an enhanced involvement of the right hippocampal formation in retained language comprehension. These findings suggest that effective language comprehension in right-handed subjects with TLE depends on the involvement of the left hippocampal formation and underline the risks of postoperative language decline in patients with left TLE.

Computer-mediated tools for the investigation and rehabilitation of auditory and phonological processing in aphasia

Background : Advances in technology have enhanced our ability to use computers to manipulate the spectrotemporal characteristics of speech waveforms in ways that can influence the processing of linguistically important features. These modifications are important in patients with auditory/phonetic processing disorders. Aims : We present some preliminary data detailing the effect of modifying the spectrotemporal structure of speech on the ability to discriminate consonant-vowel syllables and comprehend spoken words and sentences in a case of Pure Word Deafness (PWD). Methods & Procedures : We documented severe phonemic processing deficits in a patient with PWD resulting from a unilateral left temporal lesion. Her ability to distinguish between stop consonants was severely impaired while her perception of vowels was relatively spared. This pattern suggested problems with online perceptual elaboration of short-term acoustic features such as rapid formant frequency transitions. We digitally synthesised consonant-vowels with normal (40 millisecond) and extended (80 millisecond) formant frequency transitions and examined her ability to discriminate these stimuli when presented in rapid sequence. In addition, we temporally expanded natural words and sentences by 1.5 and 2 times their original duration (without altering voice pitch) and examined the effects of these manipulations on her auditory comprehension. Outcomes & Results : Altering the temporal parameters of speech had varied effects on decoding auditory linguistic information. Temporal expansion of sentences produced a small but noteworthy increase in performance on an auditory language comprehension task. Extension of brief formant transitions had no substantial effect on phonemic discrimination of rapidly presented CV pairs. Conclusions : These findings illustrate that temporal conditioning of auditory stimuli can potentially enhance the ability of patients with PWD to comprehend speech. The implications of the findings for aphasia therapy are discussed.

Evidence for altered functional connectivity in a language comprehension task following stroke

Department of Psychiatry, University of Cambridge, UKAccepted 8 July 2005Available online 16 September 2005IntroductionNeuropsychological and neuroimaging evidence suggests that theneural systems underpinning language function are instantiated in anextensive fronto-temporal network which, depending on the modalityinvolved, is more or less strongly left lateralized (Hickok & Poeppel,2000). Some differentiation exists within this system as a function ofdiffering processes

The preservation of verb subcategory knowledge in a spoken language comprehension deficit

Patient WBN has a lexical-semantic deficit resulting in impaired performance on language comprehension tasks that require access to verb meanings in both single-word and sentence contexts. However, WBN shows no such comprehension impairment with respect to lexical syntax. Specifically, he performs without error on comprehension tasks that rely on knowledge of lexical-specific verb subcategory requirements. This performance pattern supports theories of lexical representation and processing in which lexical syntactic information may be encoded and retrieved independently from lexical semantic information.

Magnetoencephalographic localization of the basal temporal language area

Magnetoencephalography (MEG) recordings were made on 25 native English-speaking patients with localization-related epilepsy during a semantic language task (verb generation). Eighteen right-handed subjects with normal reading ability had MEG scans performed during the same language task. MEG data was analyzed by MR-FOCUSS, a current density imaging technique. Detectable MEG signals arising from activation in the left fusiform gyrus, also known as the basal temporal language area (BTLA), occurred at 167 ± 18 ms ( n = 43) in all subjects. The BTLA has been associated with a variety of language production and comprehension tasks involving processing of semantic, orthographic, and phonologic information. MEG may become an important tool in efforts to further define the linguistic operations of specific regions within this language area.

Using resource allocation theory and dual‐task methods to increase the sensitivity of assessment in aphasia

Background: Quantifying the severity of language impairment and measuring change in language performance over time are two important objectives in the assessment of aphasia. The notion of cognitive effort as understood from a resource allocation perspective provides a potentially useful complement to traditional constructs employed in aphasia assessment.Aims: The series of experiments described in this paper used resource allocation theory and dual‐task methodology (1) to assess whether a language comprehension task (Story Retell Procedure) and a visual‐manual tracking task trade performance under dual‐task conditions, and (2) to investigate the potential utility of these methods in clinical assessment of aphasia. In Experiment 1, the validity of a difficulty manipulation of the SRP was investigated. In Experiments 2 and 3, the reliability and validity of the visual‐manual tracking task were evaluated. Experiment 4 investigated whether the two tasks trade performance under dual‐task conditions.Methods & Procedures: In Experiment 1, 20 normal participants listened to and retold stories presented by a normal speaker and speakers with mild, moderate, and severe aphasia. Participants' comprehension performance was measured by calculating the amount of information retold per unit time. In Experiment 2, root mean square (RMS) tracking error data were collected under fixed joystick displacement conditions. In Experiment 3, 20 normal participants performed single‐task tracking across 12 trials at each of three difficulty levels, and performance was evaluated in terms of RMS error. In Experiment 4, three groups of 20 normal individuals performed the tracking task while listening to stories told by the normal speaker and speakers with aphasia. Story retell performance was evaluated between subjects across three tracking difficulty levels and tracking performance was evaluated within subjects across story difficulty (normal, mild, moderate, and severe aphasia).Outcomes & Results: The results of Experiments 1–3 supported the reliability and validity of the difficulty manipulations for the story retell and tracking tasks. In Experiment 4, tracking performance was found to vary significantly across story difficulty, with subjects demonstrating better tracking performance while listening to stories told by a mildly aphasic speaker than during stories told by a speaker with moderate aphasia. There was no effect of tracking difficulty on story comprehension as measured by subsequent story retell performance.Conclusions: The results provide qualified support for both a resource allocation view of language performance in normal individuals and the potential utility of these methods in the assessment of aphasia. These conclusions, however, are mitigated by the finding of only a unidirectional (as opposed to bidirectional) performance trade, and by the fact that the effect of story difficulty on tracking performance was observed across only two levels of aphasia severity.

Language and memory profiles of adolescents with traumatic brain injury

The performance of adolescents who suffered a traumatic brain injury in childhood, on language comprehension tasks with varying working memory demands, was examined. It was hypothesized that adolescents with a traumatic brain injury would perform more poorly than their non-injured peers, particularly on those tasks with high working memory demands. A case study design allowed for both group and intra-participant comparisons. A battery of language comprehension and working memory tasks was administered to six adolescents aged 12–16 years. Their performance was compared with six individually age-matched peers with typical development and to the normative data of the standardized tests. Intra-participant performance was examined by comparing results across language tasks that varied in working memory demands. Analysis revealed that individuals with traumatic brain injury performed poorly compared with their age-matched peers. However, the pattern of listening comprehension impairment differed across individuals and marked variability within the comprehension profiles for some individuals with traumatic brain injury was evident. Language comprehension tasks with high working memory demands generally posed the most difficulty for individuals with traumatic brain injury.