Language Production Tasks Research Articles

Motor Response Selection in Overt Sentence Production: A Functional MRI Study

Many different cortical areas are thought to be involved in the process of selecting motor responses, from the inferior frontal gyrus, to the lateral and medial parts of the premotor cortex. The objective of the present study was to examine the neural underpinnings of motor response selection in a set of overt language production tasks. To this aim, we compared a sentence repetition task (externally constrained selection task) with a sentence generation task (volitional selection task) in a group of healthy adults. In general, the results clarify the contribution of the pre-SMA, cingulate areas, PMv, and pars triangularis to the process of selecting motor responses in the context of sentence production, and shed light on the manner in which this network is modulated by selection mode. Further, the present study suggests that response selection in sentence production engages neural resources similar to those engaged in the production of isolated words and oral motor gestures.

Dubbing projects for the language learner: a framework for integrating audiovisual translation into task-based instruction

This article describes a series of exploratory L1 to L2 dubbing projects for which students translated and used editing software to dub short American film and TV clips into their target language. Translating and dubbing into the target language involve students in multifaceted, high-level language production tasks that lead to enhanced vocabulary acquisition, register awareness, emphasis on concision, delivery practice, and mastery of paralinguistic elements. Such projects also increase learner motivation as students progress from teacher-directed, task-based instruction to self-initiated, task-based learning. Further experimental research should be conducted to generalize these findings and quantify the benefits of such dubbing projects.

Drawing as a window to event conceptualisation: Evidence from two people with aphasia

Background: There is growing interest in how problems with “thinking for speaking” (Slobin, 1996) interact with language impairment in aphasia (Marshall, 2009). Evidence to date has come from language production tasks, or from non-linguistic input-focused tasks that bear little relation to the processes involved in event communication. The current study describes a novel approach using a non-linguistic communication task, the Event Drawing Task, to investigate event conceptualisation in two people with aphasia, only one of whom is hypothesised to have problems at this level. Aims: The study aims to identify similarities and differences between the event drawing performance of the two aphasic participants and a group of 12 non-brain-damaged controls. Intact event conceptualisation (participant “Bob”) would predict a similar performance to controls, while event conceptualisation problems (participant “Jack”) would predict differences from control performance. Methods & Procedures: “Bob” and “Jack” both had severe nonfluent aphasia resulting from a single stroke. A number of background language and event-processing assessments were carried out to gain a profile of their abilities. The Event Drawing Task required participants to communicate 32 short video clips of events using only drawing. Five theoretically motivated analyses were performed on the data from the Event Drawing Task, which targeted specific aspects of event conceptualisation. Patterns within control performance were identified, which formed the basis for detailed comparison with the performance of the two people with aphasia. Outcomes & Results: As predicted, Bob's performance on the Event Drawing Task mirrored that of controls in all analyses, while Jack's performance differed widely from the controls' on a number of parameters. Importantly, characteristics of Jack's event drawing performance provide further evidence for an event conceptualisation impairment. Conclusions: The findings confirm that event conceptualisation problems may be an additional source of deficit in aphasia. Furthermore, they suggest that these problems are likely to affect non-linguistic, as well as linguistic, forms of communication. This has both theoretical and clinical implications. It suggests that we need to consider “thinking for communication” more generally, in both the assessment and remediation of severe aphasia.

Spontaneous language production in bilingual Parkinson’s disease patients: Evidence of greater phonological, morphological and syntactic impairments in native language

Nine early non-demented bilingual (L1 – Friulian, L2 – Italian) patients with Parkinson’s disease and nine normal controls matched for age, sex and years of education were studied on a spontaneous language production task. All subjects had acquired L1 from birth in a home environment and L2 at the age of six at school formally. Patients with PD evidenced more phonological, morphological and syntactic errors in L1 than in L2. The opposite pattern was observed in normal controls as far as grammar was concerned. These findings suggest that implicit language processing is more impaired than explicit language processing in Parkinson’s disease.

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.

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.

The age of second language acquisition determines the variability in activation elicited by narration in three languages in Broca’s and Wernicke’s area

It is generally accepted that the presence of a second language (L2) has an impact on the neuronal substrates build up and used for language processing; the influence of the age of L2 exposure, however, is not established. We tested the hypothesis that the age of L2 acquisition has an effect on the cortical representation of a multilingual repertoire in 44 multilinguals with different age of exposure to a L2 (simultaneous or covert simultaneous exposure to L1 and L2, sequential acquisition of L1 and L2 between 1 and 5 years, late learning of L2 after 9 years of age) and all fluent in a late learned L3. Regional activation in a language production task showed a high in-between-subject variability, which was higher than within-subject variability between L1, L2, and L3. We, therefore, performed a single subject analysis and calculated the within-subject variance in the numbers of activated voxels in Broca’s and Wernicke’s area. Subjects with early exposure to L2 showed low variability in brain activation in all three languages, in the two early as well as the late learned language. In contrast, late multilinguals exhibited higher variability. Thus, cerebral representation of languages is linked to the age of L2 acquisition: early exposure to more than one language gives rise to a language processing network that is activated homogeneously by early and late learned languages, while the inhomogeneous activation in late multilinguals indicates more independent access to the multilingual repertoire. Early passive exposure to L2 results in the same low variance as active bilingual upbringing. Variability in local brain activity increases progressively from the simultaneous to late L2 exposure, indicating a gradual transition from the mode of early bilingual language representation to that of late ones.

Long-term structural priming affects subsequent patterns of language production

This article reports three experiments exploring how experience producing particular syntactic constructions affects the rates at which those constructions will be produced in the future. In the first part of each experiment, the participants' experience at producing the double object (DO) and prepositional object (PO) constructions was manipulated so that they produced a certain proportion of DO and PO constructions. Subsequent to the establishment of these biases, the participants were given the opportunity to produce either DO or PO constructions. The main findings show that (1) patterns of experience with the DO and PO constructions affected the base rates of production for the DO and PO constructions, but not the strength of structural priming observed between particular prime sentences and particular target sentences, and (2) patterns of experience with the DO and PO constructions affected the production of subsequent sentences even across changes in the nature of the language production task. The theoretical implications of these results are discussed.

A Case Study of Primary Progressive Aphasia: Improvement on Verbs After rTMS Treatment

This case-report shows that high frequency repetitive Transcranial Magnetic Stimulation (hf-rTMS), applied to the left prefrontal cortex, may improve the linguistic skills in Primary Progressive Aphasia (PPA). The patient's performance was evaluated on a battery of language production and memory span tasks, before and after two hf-rTMS treatments and one SHAM treatment. We observed a significant and lasting improvement of the patient's performance on verb production following the application of hf-rTMS versus Baseline and SHAM conditions. This finding suggests that hf-rTMS may directly strengthen the neural connections within an area of metabolic dysfunction and encourages the use of rTMS as an alternative therapeutic tool for neurodegenerative forms of aphasia.

Do you hear what I hear? Neural correlates of thought disorder during listening to speech in schizophrenia

Thought disorder is a fundamental symptom of schizophrenia, observable as irregularities in speech. It has been associated with functional and structural abnormalities in brain regions involved in language processing, including left temporal regions, during language production tasks. We were interested in the neural correlates of thought disorder during receptive language processing, as this function is relatively preserved despite relying on the same brain regions as expressive language. Twelve patients with schizophrenia and 11 controls listened to 30-s speech samples while undergoing fMRI scanning. Thought disorder and global symptom ratings were obtained for each patient. Thought disorder but not global symptomatology correlated positively with the BOLD response in the left posterior superior temporal lobe while listening to comprehensible speech (cluster-level corrected p = .023). The pattern of brain activity associated with thought disorder during listening to comprehensible speech differs from that seen during language generation tasks, where a reduction of the leftward laterality of language has often been observed. As receptive language is spared in thought disorder, we propose that the increase in activation reflects compensatory processing allowing for normal performance.

On females' lateral and males' bilateral activation during language production: A fMRI study

This study focuses on sex/gender and language in fMRI research. We explore the question of similarities and differences in 22 men and 22 women, respectively, in a fMRI language production task of fluent narration in which covert language production was contrasted with an auditory attentional task. In women, a left-lateralised activation concentrated in BA 44 while in men activation was more frontal in BA 45 and more often bilateral. This result is the opposite of those shown so far. Interestingly, the effect is only significant at the level of group analysis; it disappears when analysing activation at the level of the individual subject. We argue that sex/gender differences in the brain should be regarded much more critically, due to the numerous variables interacting and thus confounding with sex/gender. Our present study, too, cannot resolve the controversy about the existence of sex/gender similarities and differences in fMRI-language investigations.

Hemispheric specialization for language: Brain volume matters

Increasing brain volume may impose constraints, through longer information transfer delays, on the distributed networks supporting language. Here, we assessed the relative effects of brain volume and other putative predictors of the functional variability of perisylvian language areas, as probed with PET, during both a language comprehension and a language production task. In the case of language comprehension (story listening), a linear combination of planum temporale surface, brain volume and handedness could explain almost 60% of the functional asymmetry observed in the perisylvian area. Without brain volume, the goodness of fit was significantly decreased (39%, P < 0.05), and furthermore, the effect of handedness was not detected anymore. This was due to the fact that in our sample, left-handers ( n = 12) had a significantly larger brain volume as compared to right-handers ( n = 8, P = 0.03). As for language production (verb generation), brain volume and the planum temporale also played a role. However, in this case, the main predictor of functional variability was handedness, where a greater degree of right-handedness was associated with larger activation of left inferior frontal regions. Depending on the language component of interest, these results support different (yet compatible) theories on hemispheric specialization. Left specialization for comprehension could be attributed to the constraints of processing speech stimuli, while a gestural origin of language is mostly supported by the relation we observed between left specialization for production and right-handedness.

Subcortical Aphasia

Very few neuroimaging studies have focused on follow-up of subcortical aphasia. Here, overt language production tasks were used to correlate regional cerebral blood flow (rCBF) changes and language performance in patients with vascular subcortical lesions. Seven aphasic patients were scanned twice with positron emission tomography (PET) at 1-year interval during a word-generation task. Using SPM2, Language-Rest contrast at PET1 was correlated to language performance and to time-lag from stroke. The same contrast was performed at PET2 and session effect (PET2-PET1) was correlated with performance improvement. At PET1, correlation between rCBF and delay from stroke involved mainly ventral regions of the left temporal cortex and mesial frontal cortex. Correlations between rCBF and performance showed predominantly left dorsal regions in the frontal, temporal, and parietal lobes, but also the left ventral temporal cortex. One year apart, language performance improved and rCBF increased in perisylvian regions bilaterally. Best performers at PET2 showed an increase of activity in left ventral temporal cortex as well as in right middle temporal gyrus. On follow-up, expected language improvement and increase of activation in the classical language areas and their counterparts were observed. Moreover, all correlational analyses both at PET1 and on follow-up implicated the anterior part of the left inferior temporal gyrus, suggesting a disconnection between the superior and inferior parts of the left temporal cortex and a specific role for this region in lexical semantic processing.

Amphetamine improves cognitive function in medicated individuals with schizophrenia and in healthy volunteers

Background Recent research on schizophrenia indicates that cognitive deficits in this illness are important predictors of functional outcome, highlighting the need for treatments that have a positive impact on cognitive function. Here we explore the hypothesis that acute administration of d-amphetamine can improve cognitive function in individuals with schizophrenia who are well-treated with typical antipsychotics, as well as in healthy controls performing under dual task conditions designed to elicit performance deficits analogous to those found in schizophrenia. Methods Ten individuals with schizophrenia taking haldol or prolixin and 22 healthy controls performed spatial working memory, language production, and Stroop tasks under both placebo and 0.25 mg/kg of d-amphetamine. Results d-Amphetamine improved reactions times on the spatial working memory and Stroop tasks for both individuals with schizophrenia and controls, and improved working memory accuracy in schizophrenia. In addition, d-amphetamine improved language production for both individuals with schizophrenia and controls. Conclusions These results provide support for the hypothesis that the adjunctive administration of dopamine agonist can improve cognitive in individuals with schizophrenia taking typical antipsychotics. The results are discussed in terms of their implications for understanding the nature of working memory deficits in schizophrenia, and potential future avenues for cognitive enhancement in this illness.

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.

Beeinflusst die individuelle Anpassung standardisierter Sprachparadigmen für die klinische funktionelle Magnetresonanztomographie (fMRT) die Lokalisation der sprachdominanten Hemisphäre, des Broca- und des Wernicke-Sprachzentrums?

Functional magnetic resonance imaging (fMRI) localizes Broca's area (B) and Wernicke's area (W) and the hemisphere dominant for language. In clinical fMRI, adapting the stimulation paradigms to each patient's individual cognitive capacity is crucial for diagnostic success. To interpret clinical fMRI findings correctly, we studied the effect of varying frequency and number of stimuli on functional localization, determination of language dominance and BOLD signals. Ten volunteers (VP) were investigated at 1.5 Tesla during visually triggered sentence generation using a standardized block design. In four different measurements, the stimuli were presented to each VP with frequencies of 1/1 s, (1/2) s, (1/3) s and (1/6) s. The functional localizations and the correlations of the measured BOLD signals to the applied hemodynamic reference function (r) were almost independent from frequency and number of the stimuli in both hemispheres, whereas the relative BOLD signal changes (DeltaS) in B and W increased with the stimulation rate, which also changed the lateralization indices. The strongest BOLD activations were achieved with the highest stimulation rate or with the maximum language production task, respectively. The adaptation of language paradigms necessary in clinical fMRI does not alter the functional localizations but changes the BOLD signals and language lateralization which should not be attributed to the underlying brain pathology.

VoiceRelay: Voice key operation using Visual Basic

Using a voice key is a popular method for recording vocal response times in a variety of language production tasks. This article describes a class module called VoiceRelay that can be easily utilized in Visual Basic programs for voice key operation. This software-based voice key offers the precision of traditional voice keys (although accuracy is system dependent), as well as the flexibility of volume and sensitivity control. However, VoiceRelay is a considerably less expensive alternative for recording vocal response times because it operates with existing PC hardware and does not require the purchase of external response boxes or additional experiment-generation software. A sample project demonstrating implementation of the VoiceRelay class module may be downloaded from the Psychonomic Society Web archive, www.psychonomic.org/archive.

Mechanisms for the generation and regulation of sequential behaviour

A critical aspect of much human behaviour is the generation and regulation of sequential activities. Such behaviour is seen in both naturalistic settings such as routine action and language production and laboratory tasks such as serial recall and many reaction time experiments. There are a variety of computational mechanisms that may support the generation and regulation of sequential behaviours, ranging from those underlying Turing machines to those employed by recurrent connectionist networks. This paper surveys a range of such mechanisms, together with a range of empirical phenomena related to human sequential behaviour. It is argued that the empirical phenomena pose difficulties for most sequencing mechanisms, but that converging evidence from behavioural flexibility, error data arising from when the system is stressed or when it is damaged following brain injury, and between-trial effects in reaction time tasks, point to a hybrid symbolic activation-based mechanism for the generation and regulation of sequential behaviour. Some implications of this view for the nature of mental computation are highlighted.

Neuroimaging studies of speech: An overview of techniques and methodological approaches

Over the past two decades, there has been an explosion in the use of imaging technology to study the structure and function of the human brain. The purpose of this article is to explore how functional neuroimaging has been applied to the study of speech production. This article begins with a brief review of neuroimaging methods and limitations. Then, two approaches that can be used to study the brain areas that support speech production are illustrated. The first approach is based upon comparisons across different types of language production tasks; the second approach is based upon comparing the effects of different types of stimuli within a single task. Results obtained using these approaches will be used to dissociate the contributions of different brain regions involved in speech production. For example, evidence will be presented that Broca's area contributes to phonological encoding, whereas motor cortex, the supplementary motor area (SMA), and the cerebellum support phonetic encoding and articulation. Learning outcomes: As a result of this activity, the participant will be able to describe basic methods for conducting a positron emission tomography study and a functional magnetic resonance imaging study. The participant will also be introduced to two approaches for fractionating the brain regions involved in speech production: (1) comparisons between tasks, and (2) manipulations of stimulus materials. Finally, the participant will be able to summarize a cognitive model of the components of speech production will be introduced, and potential mappings between these components and particular brain regions will be discussed.

The Selective Impairment of Phonological Processing in Speech Production

We report the naming performance of a patient (DM) with a fluent progressive aphasia who made phonological errors in all language production tasks. The pattern of errors in naming was strikingly clear: DM made very many phonological errors that resulted almost always in nonword responses. The complete absence of semantic errors and the very low ratio of formal errors relative to nonword errors (1.6:30.3) in DM's performance are discussed in the context of recent claims about the nature of naming deficits in fluent aphasics. We argue that DM's performance makes highly improbable the claim that fluent aphasia results from global lesions affecting all levels of the lexical access system equally.