Perception of grammatical tone in Akan patients with left and right hemisphere brain damage.

It remains a matter of debate what roles the left and right hemispheres play in processing speech prosody. Brain lesion studies have demonstrated that lexical tone perception among native speakers of tonal languages is more disrupted in left hemisphere damaged (LHD) individuals than right hemisphere damaged (RHD) individuals. This has been taken to suggest that linguistically-relevant prosodic cues are predominantly left-lateralised, whereas non-linguistic stimuli are predominantly right-lateralised. However, this phenomenon has only been examined in lexical tone, leaving grammatical tone perception unexplored. The aim of this study was twofold: Firstly, to examine how individuals with LHD and RHD perceive grammatical tone, and secondly to compare grammatical tone to non-linguistic tone perception. Therefore, native Akan speakers with LHD, RHD and no-brain damage (NBD) controls were tested in two discrimination tasks that examined linguistic and non-linguistic tone perception. The results showed that while both the individuals with LHD and RHD show impairment in grammatical tone perception, there was a trend of a better performance for the RHD group. Nonetheless, for non-linguistic tone perception, individuals with LHD outperformed the RHD individuals, although both had reduced performance compared to the NBD individuals. A further analysis revealed that the reduced perceptual abilities of both the LHD and RHD groups in grammatical tone perception can be attributed to grammatical problems rather than tone per se. We conclude that there is potentially a bilateral involvement of the two hemispheres in grammatical tone processing, with the left being the dominant hemisphere.

Dutch Diagnostic Instrument for Mild Aphasia (DIMA): standardisation and a first clinical application in two brain tumour patients.

Brain tumour patients with mild language disturbances are typically underdiagnosed due to lack of sensitive tests leading to negative effects in daily communicative and social life. We aim to develop a Dutch standardised test-battery, the Diagnostic Instrument for Mild Aphasia (DIMA) to detect characteristics of mild aphasia at the main linguistic levels phonology, semantics and (morpho-)syntax in production and comprehension. We designed 4 DIMA subtests: 1) repetition (words, non-words, compounds and sentences), 2) semantic odd-picture-out (objects and actions), 3) sentence completion and 4) sentence judgment (accuracy and reaction time). A normative study was carried out in a healthy Dutch-speaking population (N = 211) divided into groups of gender, age and education. Clinical application of DIMA was demonstrated in two brain tumour patients (glioma and meningioma). Standard language tests were also administered: object naming, verbal fluency (category and letter), and Token Test. Performance was at ceiling on all sub-tests, except semantic odd-picture-out actions, with an effect of age and education on most subtests. Clinical application DIMA: repetition was impaired in both cases. Reaction time in the sentence judgment test (phonology and syntax) was impaired (not accuracy) in one patient. Standard language tests: category fluency was impaired in both cases and object naming in one patient. The Token Test was not able to detect language disturbances in both cases. DIMA seems to be sensitive to capture mild aphasic deficits. DIMA is expected to be of great potential for standard assessment of language functions in patients with also other neurological diseases than brain tumours.

Comparing navigated transcranial magnetic stimulation mapping and "gold standard" direct cortical stimulation mapping in neurosurgery: a systematic review.

The objective of this systematic review is to create an overview of the literature on the comparison of navigated transcranial magnetic stimulation (nTMS) as a mapping tool to the current gold standard, which is (intraoperative) direct cortical stimulation (DCS) mapping. A search in the databases of PubMed, EMBASE, and Web of Science was performed. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and recommendations were used. Thirty-five publications were included in the review, describing a total of 552 patients. All studies concerned either mapping of motor or language function. No comparative data for nTMS and DCS for other neurological functions were found. For motor mapping, the distances between the cortical representation of the different muscle groups identified by nTMS and DCS varied between 2 and 16 mm. Regarding mapping of language function, solely an object naming task was performed in the comparative studies on nTMS and DCS. Sensitivity and specificity ranged from 10 to 100% and 13.3-98%, respectively, when nTMS language mapping was compared with DCS mapping. The positive predictive value (PPV) and negative predictive value (NPV) ranged from 17 to 75% and 57-100% respectively. The available evidence for nTMS as a mapping modality for motor and language function is discussed.

The verb and noun test for peri-operative testing (VAN-POP): standardized language tests for navigated transcranial magnetic stimulation and direct electrical stimulation.

BACKGROUND: Protocols for intraoperative language mapping with direct electrical stimulation (DES) often include various language tasks triggering both nouns and verbs in sentences. Such protocols are not readily available for navigated transcranial magnetic stimulation (nTMS), where only single word object naming is generally used. Here, we present the development, norming, and standardization of the verb and noun test for peri-operative testing (VAN-POP) that measures language skills more extensively. METHODS: The VAN-POP tests noun and verb retrieval in sentence context. Items are marked and balanced for several linguistic factors known to influence word retrieval. The VAN-POP was administered in English, German, and Dutch under conditions that are used for nTMS and DES paradigms. For each language, 30 speakers were tested. RESULTS: At least 50 items per task per language were named fluently and reached a high naming agreement. CONCLUSION: The protocol proved to be suitable for pre- and intraoperative language mapping with nTMS and DES.

Evaluating Spelling in Glioma Patients Undergoing Awake Surgery: a Systematic Review.

A main goal of awake surgery is to preserve language in order to facilitate return to work and maintain quality of life. Although spelling has become crucial in daily life, it has received little attention in awake surgery practice. We review assessments of spelling carried out in awake surgery studies, to inspect how current neurofunctional theories of spelling may guide pre-, intra- and post-operative neurosurgical practice. A systematic database search in Embase, Medline, PubMed and Web of Science identified studies reporting on spelling assessment in glioma patients undergoing awake surgery. Twenty-three studies were included, of which only 9 report details on spelling assessments. We evaluate the incidence of dysgraphia in glioma patients, the types of spelling errors as a function of tumor location, and the specificity of spelling sites with respect to other language functions. Post-operative dysgraphia arose in 26.9% of the patients with preserved pre-operative handwriting, and persisted in 45.0% of them at follow-up. Intra-operative stimulation interfered only with handwriting in 37.7% of the patients. A network of frontal, parietal and temporal regions was found to underlie central and peripheral spelling processes. Evidence on spelling performance in patients undergoing awake surgery for gliomas is surprisingly scarce. With the limitations inherent in the small number of observations, results converge with the neurofunctional knowledge accruing from studies of stroke cases. Such knowledge should be exploited in more thorough investigations of spelling skills in glioma patients. Implications for clinical and neuroscientific practice are discussed, as well as possible strategies to overcome current limitations.

The Posterior Fossa and Foreign Accent Syndrome: Report of Two New Cases and Review of the Literature.

Foreign accent syndrome is a rare motor speech disorder that causes patients to speak their language with a non-native accent. In the neurogenic condition, the disorder develops after lesions in the language dominant hemisphere, often affecting Broca's area, the insula, the supplementary motor area and the primary motor cortex. Here, we present two new cases of FAS after posterior fossa lesions. The first case is a 44-year-old, right-handed, Dutch-speaking man who suffered motor speech disturbances and a left hemiplegia after a pontine infarction. Quantified SPECT showed a bilateral hypoperfusion in the inferior lateral prefrontal and medial inferior frontal regions as well as a significant left cerebellar hypoperfusion. Further clinical investigations led to an additional diagnosis of brainstem cognitive affective syndrome which closely relates to Schmahmann's syndrome. The second patient was a 72-year-old right-handed polyglot English man who suffered a stroke in the vascular territory of the left posterior inferior cerebellar artery (PICA) and developed a foreign accent in his mother tongue (English) and in a later learnt language (Dutch). In this paper, we discuss how the occurrence of this peculiar motor speech disorder can be related to a lesion affecting the posterior fossa structures.

Overcoming discourse-linking difficulties in aphasia: The case of clitic pronouns.

The present study aims to contribute to the ongoing discussion about the impact of discourse-linking deficits on the performance of individuals with aphasia by providing new data from a set of rarely investigated constructions: sentences in which a clitic pronoun coexists alongside with the full DP it agrees with. To do so, we use data of individuals with non-fluent aphasias who need to overcome the difficulties in direct object (accusative) clitic production. This results in overproduction of non-target clitic right dislocations (RDs) and clitic doubling (CD). Data from 15 individual's native speakers of Spanish and Catalan are discussed. Data complement the results of previous investigations on discourse-linking effects in these languages, allowing the interpretation of results across constructions.

A characterization of verb use in Turkish agrammatic narrative speech.

This study investigates the characteristics of narrative-speech production and the use of verbs in Turkish agrammatic speakers (n = 10) compared to non-brain-damaged controls (n = 10). To elicit narrative-speech samples, personal interviews and storytelling tasks were conducted. Turkish has a large and regular verb inflection paradigm where verbs are inflected for evidentiality (i.e. direct versus indirect evidence available to the speaker). Particularly, we explored the general characteristics of the speech samples (e.g. utterance length) and the uses of lexical, finite and non-finite verbs and direct and indirect evidentials. The results show that speech rate is slow, verbs per utterance are lower than normal and the verb diversity is reduced in the agrammatic speakers. Verb inflection is relatively intact; however, a trade-off pattern between inflection for direct evidentials and verb diversity is found. The implications of the data are discussed in connection with narrative-speech production studies on other languages.

Perceived liveliness and speech comprehensibility in aphasia: the effects of direct speech in auditory narratives.

BACKGROUND: Previous studies have shown that in semi-spontaneous speech, individuals with Broca's and anomic aphasia produce relatively many direct speech constructions. It has been claimed that in 'healthy' communication direct speech constructions contribute to the liveliness, and indirectly to the comprehensibility, of speech. AIMS: To examine the effects of the occurrence of direct speech constructions on the perceived liveliness and speech comprehensibility of narratives produced by individuals with and without aphasia. METHODS & PROCEDURES: Thirty-seven naive listeners rated 30 speech fragments with and without direct speech from ten speakers with and ten speakers without aphasia. The fragments originated from semi-structured interviews. The raters scored the perceived liveliness and the perceived comprehensibility of these fragments. OUTCOMES & RESULTS: For both groups of speakers, fragments containing direct speech constructions received higher scores for liveliness than fragments without direct speech constructions. However, no effect of direct speech was found on perceived comprehensibility. CONCLUSIONS & IMPLICATIONS: This is the first research to demonstrate that communication is perceived as more lively when it contains direct speech than when it does not, but yet is not more comprehensible. Individuals with Broca's and anomic aphasia are known to produce regularly direct speech constructions in elicited narratives. Given that liveliness is known to increase listeners' involvement and to help listeners stay focused, we suggest that this relative increase in direct speech by aphasic speakers may reflect a strategy to increase not only the liveliness of their discourse, but also listener focus and involvement.

Representational level matters for tone-word recognition: Evidence from form priming.

In a form priming experiment with a lexical decision task, we investigated whether the representational structure of lexical tone in lexical memory impacts spoken-word recognition in Mandarin. Target monosyllabic words were preceded by five types of primes: (1) the same real words (/lun4/-/lun4/), (2) real words with only tone contrasts (/lun2/-/lun4/), (3) unrelated real words (/pie3/-/lun4/), (4) pseudowords with only tone contrasts (*/lun3/-/lun4/), and (5) unrelated pseudowords (*/tai3/-/lun4/). We found a facilitation effect in target words with pseudoword primes that share the segmental syllable but contrast in tones (*/lun3/-/lun4/). Moreover, no evident form priming effect was observed in target words primed by real words with only tone contrasts (/lun2/-/lun4/). These results suggest that the recognition of a tone word is influenced by the representational level of tone accessed by the prime word. The distinctive priming patterns between real-word and pseudoword primes are best explained by the connectionist models of tone-word recognition, which assume a hierarchical representation of lexical tone.

Neuroimaging in aphasia treatment research: standards for establishing the effects of treatment.

The goal of this paper is to discuss experimental design options available for establishing the effects of treatment in studies that aim to examine the neural mechanisms associated with treatment-induced language recovery in aphasia, using functional magnetic resonance imaging (fMRI). We present both group and single-subject experimental or case-series design options for doing this and address advantages and disadvantages of each. We also discuss general components of and requirements for treatment research studies, including operational definitions of variables, criteria for defining behavioral change and treatment efficacy, and reliability of measurement. Important considerations that are unique to neuroimaging-based treatment research are addressed, pertaining to the relation between the selected treatment approach and anticipated changes in language processes/functions and how such changes are hypothesized to map onto the brain.

Why reference to the past is difficult for agrammatic speakers.

Many studies have shown that verb inflections are difficult to produce for agrammatic aphasic speakers: they are frequently omitted and substituted. The present article gives an overview of our search to understanding why this is the case. The hypothesis is that grammatical morphology referring to the past is selectively impaired in agrammatic aphasia. That is, verb inflections for past tense and perfect aspect are hard to produce. Furthermore, verb clusters that refer to the past will be affected as well, even if the auxiliary is in present tense, as in he has been writing a letter. It will be argued that all these verb forms referring to the past require discourse linking [Zagona, K. (2003). Tense and anaphora: Is there a tense-specific theory of coreference. In A. Barrs (Ed.), Anaphora: A reference guide (pp. 140-171). Oxford: Blackwell Publishing] and discourse linking is affected in agrammatic aphasia [Avrutin, S. (2006). Weak syntax. In K. Amunts, & Y. Grodzinsky (Eds.), Broca's region (pp. 49-62). New York: Oxford Press]. This hypothesis has been coined the PAst DIscourse LInking Hypothesis (PADILIH) [Bastiaanse, R., Bamyaci, E., Hsu, C.-J., Lee, J., Yarbay Duman, T., & Thompson, C.K. (2011). Time reference in agrammatic aphasia: A cross-linguistic study. Journal of Neurolinguistics, 24, 652-673]. The PADILIH has been tested in several languages and populations that have hardly been studied before in aphasiology: languages such as Turkish, Swahili and Indonesian were included, as well as monolingual and bilingual populations. In all these populations, the same test has been used: the Test for Assessing Reference of Time [Bastiaanse, R., Jonkers, R., & Thompson, C.K. (2008). Test for assessing reference of time (TART). Groningen: University of Groningen] to enable reliable comparisons between the languages. The results show that the PADILIH predicts the performance of agrammatic speakers very well: discourse-linked grammatical morphemes expressing time reference to the past are hard to produce for agrammatic speakers, whereas non-discourse-linked verb inflections (for present and future) are relatively spared. In languages that use aspectual adverbs (free-standing and optional time reference markers), such as Chinese and Indonesian, time reference to all time frames is impaired, since all aspectual adverbs, regardless of the time frame they refer to, require discourse linking. Remarkably, the problems are not restricted to grammatical morphemes: the production of temporal lexical adverbs is impaired as well.

Sentence comprehension in Swahili-English bilingual agrammatic speakers.

For this study, sentence comprehension was tested in Swahili-English bilingual agrammatic speakers. The sentences were controlled for four factors: (1) order of the arguments (base vs. derived); (2) embedding (declarative vs. relative sentences); (3) overt use of the relative pronoun "who"; (4) language (English and Swahili). Two theories were tested: the Trace Deletion Hypothesis (TDH; [Grodzinsky, Y. (1995). A restrictive theory of agrammatic comprehension. Brain and Language, 50, 27-51]) that assumes a representational deficit in agrammatic aphasia and the Derived Order Problem Hypothesis (DOP-H; Bastiaanse & Van Zonneveld, 2005), which is a processing account. Both theories have the same predictions for sentences in derived order. The difference is that the TDH predicts chance level performance for sentences in which the arguments are not in base order, whereas the DOP-H predicts poorer performance when processing demands increase. The results show that word order influences performance, in that sentences in which the arguments are in derived order are harder to comprehend than sentences in which the arguments are in base order. However, there is a significant interaction with the factor "embedding": sentences with an embedding are harder to comprehend than simple declaratives and this influence is larger in derived order sentences. There is no effect of language nor of the use of a relative pronoun. These results are correctly accounted for by the DOP-H.

Presurgical Language Mapping: What Are We Testing?

Gliomas are brain tumors infiltrating healthy cortical and subcortical areas that may host cognitive functions, such as language. If these areas are damaged during surgery, the patient might develop word retrieval or articulation problems. For this reason, many glioma patients are operated on awake, while their language functions are tested. For this practice, quite simple tests are used, for example, picture naming. This paper describes the process and timeline of picture naming (noun retrieval) and shows the timeline and localization of the distinguished stages. This is relevant information for presurgical language testing with navigated Magnetic Stimulation (nTMS). This novel technique allows us to identify cortical involved in the language production process and, thus, guides the neurosurgeon in how to approach and remove the tumor. We argue that not only nouns, but also verbs should be tested, since sentences are built around verbs, and sentences are what we use in daily life. This approach's relevance is illustrated by two case studies of glioma patients.

Corrigendum: Does a walk-through video help the parser down the garden-path? A visually enhanced self-paced reading study in Dutch.

[This corrects the article DOI: 10.3389/fpsyg.2022.1009265.].

Does a walk-through video help the parser down the garden-path? A visually enhanced self-paced reading study in Dutch.

The human language processing mechanism assigns a structure to the incoming materials as they unfold. There is evidence that the parser prefers some attachment types over others; however, theories of sentence processing are still in dispute over the stage at which each source of information contributes to the parsing system. The present study aims to identify the nature of initial parsing decisions during sentence processing through manipulating attachment type and verbs' argument structure. To this end, we designed a self-paced reading task using globally ambiguous constructions in Dutch. The structures included double locative prepositional phrases (PPs) where the first PP could attach both to the verb (high attachment) and the noun preceding it (low attachment). To disambiguate the structures, we presented a visual context in the form of short animation clips prior to each reading task. Furthermore, we manipulated the argument structure of the sentences using 2- and 3-argument verbs. The results showed that parsing decisions were influenced by contextual cues depending on the argument structure of the verb. That is, the visual context overcame the preference for high attachment only in the case of 2-argument verbs, while this preference persisted in structures including 3-argument verbs as represented by longer reading times for the low attachment interpretations. These findings can be taken as evidence that our language processing system actively integrates information from linguistic and non-linguistic sources from the initial stages of analysis to build up meaning. We discuss our findings in light of serial and parallel models of sentence processing.

Distinct Slow-Wave Activity Patterns in Resting-State Electroencephalography and Their Relation to Language Functioning in Low-Grade Glioma and Meningioma Patients.

Introduction: Brain tumours frequently cause language impairments and are also likely to co-occur with localised abnormal slow-wave brain activity. However, it is unclear whether this applies specifically to low-grade brain tumours. We investigate slow-wave activity in resting-state electroencephalography (EEG) in low-grade glioma and meningioma patients, and its relation to pre- and postoperative language functioning. Method: Patients with a glioma (N = 15) infiltrating the language-dominant hemisphere and patients with a meningioma (N = 10) with mass effect on this hemisphere underwent extensive language testing before and 1 year after surgery. EEG was registered preoperatively, postoperatively (glioma patients only), and once in healthy individuals. Slow-wave activity in delta- and theta- frequency bands was evaluated visually and quantitatively by spectral power at three levels over the scalp: the whole brain, the affected hemisphere, and the affected region. Results: Glioma patients had increased delta activity (affected area) and increased theta activity (all levels) before and after surgery. In these patients, increased preoperative theta activity was related to the presence of language impairment, especially to poor word retrieval and grammatical performance. Preoperative slow-wave activity was also related to postoperative language outcomes. Meningioma patients showed no significant increase in EEG slow-wave activity compared to healthy individuals, but they presented with word retrieval, grammatical, and writing problems preoperatively, as well as with writing impairments postoperatively. Discussion: Although the brain-tumour pathology in low-grade gliomas and meningiomas has a different effect on resting-state brain activity, patients with low-grade gliomas and meningiomas both suffer from language impairments. Increased theta activity in glioma patients can be considered as a language-impairment marker, with prognostic value for language outcome after surgery.

Time reference in agrammatic aphasia: A cross-linguistic study.

It has been shown across several languages that verb inflection is difficult for agrammatic aphasic speakers. In particular, Tense inflection is vulnerable. Several theoretical accounts for this have been posed, for example, a pure syntactic one suggesting that the Tense node is unavailable due to its position in the syntactic tree (Friedmann & Grodzinsky, 1997); one suggesting that the interpretable features of the Tense node are underspecified (Burchert, Swoboda-Moll, & De Bleser, 2005; Wenzlaff & Clahsen, 2004, 2005); and a morphosemantic one, arguing that the diacritic Tense features are affected in agrammatism (Faroqi-Shah & Dickey, 2009; Lee, Milman, & Thompson, 2008). However recent findings (Bastiaanse, 2008) and a reanalysis of some oral production studies (e.g. Lee et al., 2008; Nanousi, Masterson, Druks, & Atkinson, 2006) suggest that both Tense and Aspect are impaired and, most importantly, reference to the past is selectively impaired, both through simple verb forms (such as simple past in English) and through periphrastic verb forms (such as the present perfect, 'has V-ed', in English). It will be argued that reference to the past is discourse linked and reference to the present and future is not (Zagona, 2003, in press). In-line with Avrutin's (2000) theory that suggests discourse linking is impaired in Broca's aphasia, the PAst DIscourse LInking Hypothesis (PADILIH) has been formulated. Three predictions were tested: (1) patients with agrammatic aphasia are selectively impaired in use of grammatical morphology associated with reference to the past, whereas, inflected forms which refer to the present and future are relatively spared; (2) this impairment is language-independent; and (3) this impairment will occur in both production and comprehension. Agrammatic Chinese, English and Turkish speakers were tested with the Test for Assessing Reference of Time (TART; Bastiaanse, Jonkers, & Thompson, unpublished). Results showed that both the English and Turkish agrammatic speakers performed as hypothesized, showing a selective deficit for production of inflected forms referring to the past, despite the typological difference between the languages. The Chinese agrammatic speakers were poor in reference to the past as well, but reference to the present and future also was severely impaired. For comprehension, the results were strikingly similar for the three languages: reference to the past was impaired for all. These results confirmed our hypothesis that reference to the past is discourse linked and, therefore, grammatical morphology used for reference to the past is impaired in agrammatic aphasia, whether this is done through Tense and/or Aspect markers.

Online Processing of Temporal Agreement in a Grammatical Tone Language: An ERP Study.

Previous electrophysiological studies that have examined temporal agreement violations in (Indo-European) languages that use grammatical affixes to mark time reference, have found a Left Anterior Negativity (LAN) and/or P600 ERP components, reflecting morpho-syntactic and syntactic processing, respectively. The current study investigates the electrophysiological processing of temporal relations in an African language (Akan) that uses grammatical tone, rather than morphological inflection, for time reference. Twenty-four native speakers of Akan listened to sentences with time reference violations. Our results demonstrate that a violation of a present context by a past verb yields a P600 time-locked to the verb. There was no such effect when a past context was violated by a present verb. In conclusion, while there are similarities in both Akan and Indo-European languages, as far as the modulation of the P600 effect is concerned, the nature of this effect seems to be different for these languages.

Mapping Verb Retrieval With nTMS: The Role of Transitivity.

Navigated Transcranial Magnetic Stimulation (nTMS) is used to understand the cortical organization of language in preparation for the surgical removal of a brain tumor. Action naming with finite verbs can be employed for that purpose, providing additional information to object naming. However, little research has focused on the properties of the verbs that are used in action naming tasks, such as their status as transitive (taking an object; e.g., to read) or intransitive (not taking an object; e.g., to wink). Previous neuroimaging data show higher activation for transitive compared to intransitive verbs in posterior perisylvian regions bilaterally. In the present study, we employed nTMS and production of finite verbs to investigate the cortical underpinnings of transitivity. Twenty neurologically healthy native speakers of German participated in the study. They underwent language mapping in both hemispheres with nTMS. The action naming task with finite verbs consisted of transitive (e.g., The man reads the book) and intransitive verbs (e.g., The woman winks) and was controlled for relevant psycholinguistic variables. Errors were classified in four different error categories (i.e., non-linguistic errors, grammatical errors, lexico-semantic errors and, errors at the sound level) and were analyzed quantitatively. We found more nTMS-positive points in the left hemisphere, particularly in the left parietal lobe for the production of transitive compared to intransitive verbs. These positive points most commonly corresponded to lexico-semantic errors. Our findings are in line with previous aphasia and neuroimaging studies, suggesting that a more widespread network is used for the production of verbs with a larger number of arguments (i.e., transitives). The higher number of lexico-semantic errors with transitive compared to intransitive verbs in the left parietal lobe supports previous claims for the role of left posterior areas in the retrieval of argument structure information.