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An emerging area of research in cognitive science is the utilization of networks to model the structure and processes of the mental lexicon in healthy and clinical populations, like aphasia. Previous research has focused on only one type of word similarity at a time (e.g., semantic relationships), even though words are multi-faceted. Here, we investigate lexical retrieval in a picture naming task from people with Broca’s and Wernicke’s aphasia and healthy controls by utilizing a multiplex network structure that accounts for the interplay between multiple semantic and phonological relationships among words in the mental lexicon. Extending upon previous work, we focused on the global network measure of closeness centrality which is known to capture spreading activation, an important process supporting lexical retrieval. We conducted a series of logistic regression models predicting the probability of correct picture naming. We tested whether multiplex closeness centrality was a better predictor of picture naming performance than single-layer closeness centralities, other network measures assessing local and meso-scale structure, psycholinguistic variables and group differences. We also examined production gaps, or the difference between the likelihood of producing a word with the lowest and highest closeness centralities. Our results indicated that multiplex closeness centrality was a significant predictor of picture naming performance, where words with high closeness centrality were more likely to be produced than words with low closeness centrality. Additionally, multiplex closeness centrality outperformed single-layer closeness centralities and other multiplex network measures, and remained a significant predictor after controlling for psycholinguistic variables and group differences. Furthermore, we found that the facilitative effect of closeness centrality was similar for both types of aphasia. Our results underline the importance of integrating multiple measures of word similarities in cognitive language networks for better understanding lexical retrieval in aphasia, with an eye towards future clinical applications.

Background Opioid use disorder (OUD) is characterized by the inability to control opioid use despite attempts to stop use and negative consequences to oneself and others. The burden of opioid misuse and OUD is a national crisis in the United States with substantial public health, social, and economic implications. Although medication-assisted treatment (MAT) has demonstrated efficacy in the management of OUD, access to effective counseling and psychosocial support is a limiting factor and a significant problem for many patients and physicians. Digital therapeutics are an innovative class of interventions that help prevent, manage, or treat diseases by delivering therapy using software programs. These applications can circumvent barriers to uptake, improve treatment adherence, and enable broad delivery of evidence-based management strategies to meet service gaps. However, few digital therapeutics specifically targeting OUD are available, and additional options are needed. Objective To this end, we describe the development of the novel digital therapeutic MODIA. Methods MODIA was developed by an international, multidisciplinary team that aims to provide effective, accessible, and sustainable management for patients with OUD. Although MODIA is aligned with principles of cognitive behavioral therapy, it was not designed to present any 1 specific treatment and uses a broad range of evidence-based behavior change techniques drawn from cognitive behavioral therapy, mindfulness, acceptance and commitment therapy, and motivational interviewing. Results MODIA uses proprietary software that dynamically tailors content to the users’ responses. The MODIA program comprises 24 modules or “chats” that patients are instructed to work through independently. Patient responses dictate subsequent content, creating a “simulated dialogue” experience between the patient and program. MODIA also includes brief motivational text messages that are sent regularly to prompt patients to use the program and help them transfer therapeutic techniques into their daily routines. Thus, MODIA offers individuals with OUD a custom-tailored, interactive digital psychotherapy intervention that maximizes the personal relevance and emotional impact of the interaction. Conclusions As part of a clinician-supervised MAT program, MODIA will allow more patients to begin psychotherapy concurrently with opioid maintenance treatment. We expect access to MODIA will improve the OUD management experience and provide sustainable positive outcomes for patients.

The age-old debates about the localization of the mind (higher functions) took a new course when Willis located a higher nervous function (memory) in the brain parenchyma, and supposedly, in the cerebral cortex. About two centuries later, Broca, founded on solid scientific reasoning, localized a circumscribed area of the 3Os debates milenares sobre a localização da mente (funções superiores) chegaram a um novo caminho quando Willis localizou uma função nervosa superior (memória) no parênquima cerebral, e supostamente, no córtex cerebral. Cerca de dois séculos depois, Broca, baseado em sólido pensamento científico, localizou uma área circunscrita da 3ª circunvolução frontal do hemisfério esquerdo como o sítio da linguagem articulada, uma função superior (fala - domínio da linguagem). Ele (e Dax) também definiu a assimetria funcional (especialização) dos hemisférios, com dominância esquerda (para linguagem). O período entre os achados dessas duas personalidades não ficou quiescente, considerando que numerosos autores contribuíram, com suas pesquisas teóricas e clinicopatológicas, para criar uma atmosfera científica adequada para tal realização, devendo ser vistos como importantes. Mais estudos, nas décadas seguintes, revelaram a localização de aspectos adicionais da linguagem e de outras funções superiores (domínios cognitivos).

Frontiers in psychology 11, 582 (2020). doi:10.3389/fpsyg.2020.00582, Published by Frontiers Research Foundation, Lausanne

Recent studies by Bastiaanse and colleagues found that time reference is selectively impaired in people with nonfluent agrammatic aphasia, with reference to the past being more difficult to process than reference to the present or to the future. To account for this dissociation, they formulated the PAst DIscourse LInking Hypothesis (PADILIH), which posits that past reference is more demanding than present/future reference because it involves discourse linking. There is some evidence that this hypothesis can be applied to people with fluent aphasia as well. However, the existing evidence for the PADILIH is contradictory, and most of it has been provided by employing a test that predominantly taps retrieval processes, leaving largely unexplored the underlying ability to encode time reference-related prephonological features. Within a cross-linguistic approach, this study tests the PADILIH by means of a sentence completion task that 'equally' taps encoding and retrieval abilities. This study also investigates if the PADILIH’s scope can be extended to fluent aphasia. Greek- and Italian-speaking individuals with aphasia participated in the study. The Greek group consisted of both individuals with nonfluent agrammatic aphasia and individuals with fluent aphasia, who also presented signs of agrammatism. The Italian group consisted of individuals with agrammatic nonfluent aphasia only. The two Greek subgroups performed similarly. Neither language group of participants with aphasia exhibited a pattern of performance consistent with the predictions of the PADILIH. However, a double dissociation observed within the Greek group suggests a hypothesis that may reconcile the present results with the PADILIH.

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.

El presente artículo establece como objetivo conocer el desarrollo auditivo que experimentan niños y niñas otológicamente sanos durante la primera infancia, porque el profesorado de educación preescolar debe contar con documentación objetiva que aborde la materia para mejorar y potenciar su trabajo didáctico en el aula. Se recurre a bibliografía clásica de las ciencias de la salud y la psicología, normas internacionales sobre umbrales de audición e investigaciones validadas; abordando el desarrollo de la discriminación tonal, la localización de sonidos en el espacio y el impacto de la audición en el desarrollo integral infantil. Se concluye que el desarrollo auditivo durante la primera infancia no se limita al aspecto fisiológico, sino que también cobran relevancia los factores sensoriales, sensorio-motores y perceptivo-cognitivos. This article aims to know about hearing development experienced by otologically healthy children during their early childhood, in order to give an objective documentation about the matter to preschool education teachers, so that they can improve and enhance their didactic work in the classroom. The research uses classic bibliography in health sciences and psychology, international standards on hearing thresholds, and validated researches addressing the development of tonal discrimination, localization of sounds in space, and the impact of hearing on integral child development. It is concluded that the hearing development in early childhood is not limited to physiological aspect, but it also involves other factors such as sensory, sensorimotor, perceptual and cognitive ones.

In the nineteenth century, French scientific institutions became interested in young "mental calculators," arithmetical prodigies able to quickly and accurately perform complex mental calculations. The first scientists to study mental calculators were phrenologists who sought to prove the existence of a calculating organ in the frontal lobe. Paul Broca introduced one such mental calculator, Jacques Inaudi, to the Anthropological Society of Paris in 1880. Broca attributed extraordinary faculty for mental calculation to memory functioning (the psychological hypothesis) rather than physiological difference (the phrenological hypothesis). In 1892, prominent French Academy of Sciences member Jean-Martin Charcot produced a noteworthy study of Inaudi on the organization's behalf. Charcot observed that Inaudi called upon auditory memory rather than visual memory in his mental calculations, unlike most mental calculators who preceded him. Like Broca, Charcot was skeptical of the phrenological hypothesis, though he noted that Inaudi's skull was markedly plagiocephalic. Interestingly, anthropological examination of Inaudi is consistent with the themes of modern cognitive neuroscience. Thus, Charcot seems to have anticipated present research on the localization of mental calculation and memory for numbers. 1. (1)The Academy of Sciences, founded in 1666 by Louis XIV (1638-1715) with the goal of contributing to the advancement and application of the sciences in France, was one of the earliest European scientific institutions. As a prestigious society, it played an active role in defining scientific and technological research policy as well as drafting and publishing official reports.

Contains fulltext : 214257.pdf (Publisher’s version ) (Closed access) While the involvement of the left inferior frontal gyrus (IFG) in language production is undisputed, the role of specific subregions at different representational levels remains unclear. Some studies suggest a division of anterior and posterior regions for semantic and phonological processing, respectively. Crucially, evidence thus far only comes from correlative neuroimaging studies, but the functional relevance of the involvement of these subregions during a given task remains elusive. We applied repetitive transcranial magnetic stimulation (rTMS) over anterior and posterior IFG (aIFG/pIFG), and vertex as a control site, while participants performed a category member and a rhyme generation task. We found a functional-anatomical double dissociation between tasks and subregions. Naming latencies were significantly delayed in the semantic task when rTMS was applied to aIFG (relative to pIFG and vertex). In contrast, we observed a facilitation of naming latencies in the phonological task when rTMS was applied to pIFG (relative to aIFG and vertex). The results provide first causal evidence for the notion that anterior portions of the IFG are selectively recruited for semantic processing while posterior regions are functionally specific for phonological processing during word production. These findings shed light on the functional parcellation of the left IFG in language production. 9 p.

Classification is the process of grouping similar entities under one category for the ease of their comprehension and better handling. Medical classification dates back to the days of William Farr who is credited with the development of a nosology, which later served as the forerunner for the modern-day disease classification by ICD. The WHO system of classification is a time-honoured system that has prevailed from decades together and is under constant evolution. The classification of odontogenic tumours was first formulated by Pierre Paul Broca and has undergone several transformations over years. Though the earlier classifications and their modifications by several authors and even by the WHO appeared to be fitting for their time, the latest edition of WHO classification of odontogenic and maxillofacial bone tumours neither seems to be complete nor perfect, even at the present context. It is unfortunate that even with the advancement of molecular biology, the present WHO classification on Odontogenic and Maxillofacial bone tumours, fails to serve as a ‘reference standard’ in the true sense of the term. This article highlights the limitations of the current classification with constructive criticism that may help in further improvement.

Background: The background to this study is that aphasiologists have increasingly started to pay attention not only to the speech that people with aphasia produce, but also to their gestures. As there are a number of competing models about the production of gesture and speech in healthy subjects, it is important to evaluate whether, and if so how, these models could be used to guide the research into gesture and speech, and the relationship between these, in speakers with aphasia.Aims: The aims and objectives of this study are to see how existing models of gesture and speech are able to accommodate the findings regarding the gesture and speech behaviour of speakers with aphasia, in the hope that (1) these models could shed light on the use of gesture in aphasic speakers, and potentially suggest new approaches to therapy for people with aphasia and (2) the aphasia gesture data might help fundamental psycholinguistics to evaluate the adequacy of existing gesture and speech models.Methods & Procedures: The methodology here was theoretical. Four models of gesture and speech interaction were critiqued and we reviewed their ability to explain some of the central empirical findings in the area of gesture and speech in aphasia.Outcomes & Results: The outcomes and results of this theoretical analysis were that, with respect to the relationship between gesture and speech in aphasia, (1) the four models under investigation could be reduced to two models, because three of the investigated models were based on the same core assumptions and (2) both of these models adequately explain these findings, but the Growth Point/Sketch/Interface Model is more satisfactory than the Lexical Access Model, because of the better fit with the experimental results on the use of gesture for facilitating word finding, and because it is more compatible with the finding that gestures are also used to enhance communicative efficiency by replacing speech.Conclusions: The two main conclusions from this study were that both the Growth Point/Sketch/Interface Model and the Lexical Access Model are compatible with data on gesture and speech in aphasia, and that the former appears to be preferable on the basis of the evidence available so far.

Because Broca's area is known to be involved in many cognitive functions, including language, music, and action processing, several attempts have been made to propose a unifying theory of its role that emphasizes a possible contribution to syntactic processing. Recently, we have postulated that Broca's area might be involved in higher-order chunk processing during implicit learning of a motor sequence. Chunking is an information-processing mechanism that consists of grouping consecutive items in a sequence and is likely to be involved in all of the aforementioned cognitive processes. Demonstrating a contribution of Broca's area to chunking during the learning of a nonmotor sequence that does not involve language could shed new light on its function. To address this issue, we used offline MRI-guided TMS in healthy volunteers to disrupt the activity of either the posterior part of Broca's area (left Brodmann's area [BA] 44) or a control site just before participants learned a perceptual sequence structured in distinct hierarchical levels. We found that disruption of the left BA 44 increased the processing time of stimuli representing the boundaries of higher-order chunks and modified the chunking strategy. The current results highlight the possible role of the left BA 44 in building up effector-independent representations of higher-order events in structured sequences. This might clarify the contribution of Broca's area in processing hierarchical structures, a key mechanism in many cognitive functions, such as language and composite actions.

A number of studies have shown that modulating cortical activity by means of transcranial direct current stimulation (tDCS) affects performances of both healthy and brain-damaged subjects. In this study, we investigated the potential of tDCS to enhance associative verbal learning in 10 healthy individuals and to improve word retrieval deficits in three patients with stroke-induced aphasia. In healthy individuals, tDCS (20 min, 1 mA) was applied over Wernicke's area (position CP5 of the International 10–20 EEG System) while they learned 20 new “words” (legal nonwords arbitrarily assigned to 20 different pictures). The healthy subjects participated in a randomized counterbalanced double-blind procedure in which they were subjected to one session of anodic tDCS over left Wernicke's area, one sham session over this location and one session of anodic tDCS stimulating the right occipito-parietal area. Each experimental session was performed during a different week (over three consecutive weeks) with 6 days of intersession interval. Over 2 weeks, three aphasic subjects participated in a randomized double-blind experiment involving intensive language training for their anomic difficulties in two tDCS conditions. Each subject participated in five consecutive daily sessions of anodic tDCS (20 min, 1 mA) and sham stimulation over Wernicke's area while they performed a picture-naming task. By the end of each week, anodic tDCS had significantly improved their accuracy on the picture-naming task. Both normal subjects and aphasic patients also had shorter naming latencies during anodic tDCS than during sham condition. At two follow-ups (1 and 3 weeks after the end of treatment), performed only in two aphasic subjects, response accuracy and reaction times were still significantly better in the anodic than in the sham condition, suggesting a long-term effect on recovery of their anomic disturbances.

We describe three cases of aphasia in patients who were internationally famous historical personalities, such as the case of Mr. Leborgne ("Tan") published by Paul Broca in 1861, which became a reference for the study of aphasias. The other cases described here are those of the Russian revolutionary and politician Vladimir Ilyitch Ulianov (Lenin) ("Vot-vot") and the French poet Charles Baudelaire ("Cré nom!"). Besides their historical relevance and the clinical picture of aphasia, these three cases share as a common feature the occurrence of speech automatisms or stereotypes. São apresentados três casos de afasia que ocorreram em personalidades famosas da história mundial, como o do Sr. Leborgne ("Tan"), publicado por Paul Broca, em 1861, que se tornou o caso princeps no estudo das afasias. Os outros casos apresentados são a afasia do político e revolucionário russo Vladimir Ilyitch Ulianov (Lênin) ("Vot-vot") e do poeta francês Charles Baudelaire ("Cré nom!"). Além de sua relevância histórica e do quadro clínico de afasia, estes três casos têm em comum a presença de automatismos ou estereotipias verbais.

Aphasia is a complex disorder, frequent after stroke (with an incidence of 38%), with a detailed pathophysiological characterization. Effective approaches are crucial for devising an efficient rehabilitative strategy, in order to address the everyday life and professional disability. Several rehabilitative procedures are based on psycholinguistic, cognitive, psychosocial or pragmatic approaches, including amongst those with a neurobehavioral approach the Melodic Intonation Therapy (MIT). Van Eeckhout's adaptation of MIT to French language (Melodic-Rhythmic Therapy: MRT) has implemented the training strategy by adding a rhythmic structure reproducing French prosody. The purpose of this study was to adapt MRT rehabilitation procedures to Italian language and to verify its efficacy in a group of six chronic patients (five males) with severe non-fluent aphasia and without specific aphasic treatments during the previous 9 months. The patients were treated 4 days a week for 16 weeks, with sessions of 30-40 min. They were assessed 6 months after the end of the treatment (follow-up). The patients showed a significant improvement at the Aachener Aphasie Test (AAT) in different fields of spontaneous speech, with superimposable results at the follow-up. Albeit preliminary, these findings support the use of MRT in the rehabilitation after stroke. Specifically, MRT seems to benefit from its stronger structure than the available stimulation-facilitation procedures and allows a better quantification of the rehabilitation efficacy.

Background and Objective: Modern neuroimaging developments have demonstrated that cognitive functions correlate with brain networks rather than specific areas. The purpose of this paper was to analyze the connectivity of Broca’s area based on language tasks. Methods: A connectivity modeling study was performed by pooling data of Broca’s activation in language tasks. Fifty-seven papers that included 883 subjects in 84 experiments were analyzed. Analysis of Likelihood Estimates of pooled data was utilized to generate the map; thresholds at p < 0.01 were corrected for multiple comparisons and false discovery rate. Resulting images were co-registered into MNI standard space. Results: A network consisting of 16 clusters of activation was obtained. Main clusters were located in the frontal operculum, left posterior temporal region, supplementary motor area, and the parietal lobe. Less common clusters were seen in the sub-cortical structures including the left thalamus, left putamen, secondary visual areas, and the right cerebellum. Conclusion: Broca’s area-44-related networks involved in language processing were demonstrated utilizing a pooling-data connectivity study. Significance, interpretation, and limitations of the results are discussed.

With the advent of non-invasive brain stimulation (NIBS), a new decade in the study of language has started. NIBS allows for testing the functional relevance of language-related brain activation and enables the researcher to investigate how neural activation changes in response to focal perturbations. This review focuses on the application of NIBS in the healthy brain. First, some basic mechanisms will be introduced and the prerequisites for carrying out NIBS studies of language are addressed. The next section outlines how NIBS can be used to characterize the contribution of the stimulated area to a task. In this context, novel approaches such as multifocal transcranial magnetic stimulation and the condition-and-perturb approach are discussed. The third part addresses the combination of NIBS and neuroimaging in the study of plasticity. These approaches are particularly suited to investigate short-term reorganization in the healthy brain and may inform models of language recovery in post-stroke aphasia.

Objective: To identify early cognitive and neuroimaging features of sporadic nonfluent/agrammatic variant of primary progressive aphasia (nfvPPA) caused by frontotemporal lobar degeneration (FTLD) subtypes. Methods: We prospectively collected clinical, neuroimaging, and neuropathologic data in 11 patients with sporadic nfvPPA with FTLD-tau (nfvPPA-tau, n = 9) or FTLD–transactive response DNA binding protein pathology of 43 kD type A (nfvPPA-TDP, n = 2). We analyzed patterns of cognitive and gray matter (GM) and white matter (WM) atrophy at presentation in the whole group and in each pathologic subtype separately. We also considered longitudinal clinical data. Results: At first evaluation, regardless of pathologic FTLD subtype, apraxia of speech (AOS) was the most common cognitive feature and atrophy involved the left posterior frontal lobe. Each pathologic subtype showed few distinctive features. At presentation, patients with nfvPPA-tau presented with mild to moderate AOS, mixed dysarthria with prominent hypokinetic features, clear agrammatism, and atrophy in the GM of the left posterior frontal regions and in left frontal WM. While speech and language deficits were prominent early, within 3 years of symptom onset, all patients with nfvPPA-tau developed significant extrapyramidal motor signs. At presentation, patients with nfvPPA-TDP had severe AOS, dysarthria with spastic features, mild agrammatism, and atrophy in left posterior frontal GM only. Selective mutism occurred early, when general neurologic examination only showed mild decrease in finger dexterity in the right hand. Conclusions: Clinical features in sporadic nfvPPA caused by FTLD subtypes relate to neurodegeneration of GM and WM in frontal motor speech and language networks. We propose that early WM atrophy in nfvPPA is suggestive of FTLD-tau pathology while early selective GM loss might be indicative of FTLD-TDP.

Though activation of Broca's region in the combinatorial processing of symbols (language, music) has been revealed by neurometabolic studies, most previous neurophysiological research found the earliest grammar indices in the temporal cortex, with inferior-frontal generators becoming active at relatively late stages. We use the attention- and task-free syntactic mismatch negativity (sMMN) event-related potential (ERP) to measure rapid and automatic sensitivity of the human brain to grammatical information in participants' native language (French). Further, sources underlying the MMN were estimated by applying the Parametrical Empirical Bayesian (PEB) approach, with the Multiple Sparse Priors (MSP) technique. Results showed reliable grammar-related activation focused on Broca's region already in the 150-190 ms time window, providing robust documentation of its involvement in the first stages of syntactic processing.

The age difference observed between Wernicke's and Broca's aphasics has been understood by some authors as an indication of a progressive diminution of the contribution of the right hemisphere to language throughout the life span. To test this hypothesis, 24 right-hemisphere-damaged (RHD) and 24 normal control adults were submitted to six tasks looking at different aspects of language abilities. Results showed that RHDs performed less well than normal subjects on 3 of these tasks, but that this difference was not linked with age (younger than 55 versus older than 65 years). Consequently, these results do not support models of functional brain organization suggesting a decreasing contribution of the right hemisphere to language abilities with age.

In an earlier study by the authors, it was suggested that some fluent aphasic speakers exhibit subtle grammatical deficits. In this paper, how far lexical accessing problems might account for these deficits is considered. For this study, spontaneous speech data collected from two groups of aphasic speakers, Dutch and English, and from normal controls are analysed. As expected, differences are found between the aphasic and the control groups. The English aphasic group was significantly different from the control group on lexical and grammatical measures. There was a significant difference between the Dutch aphasic group and the normal controls for one lexical measure (types and tokens of nouns used) and for one grammatical measure, the proportion of embedded clauses used. The relationship between the aphasic speakers' grammatical and lexical abilities is explored by comparing the distribution of clausal structures with the frequency and diversity of verb and noun use. A number of dissociations are found between the grammatical and the lexical measures within the aphasic groups which suggests that difficulty with lexical accessing may not always account for the grammatical limitations of fluent aphasics.

Previous studies of category-specific semantic disturbances have focused their attention on the intrinsic cognitive structure of these disorders. The present survey aims to evaluate the relationships between disrupted semantic category and localisation of the underlying brain damage, in order to establish whether the injured brain areas house just those neurophysiological mechanisms that should have critically contributed to the acquisition of the disrupted semantic categories. We took into account in our review two double dissociations concerning respectively: (1) the impairment of a specific linguistic category--we contrast those disorders selectively affecting verbs (action names) with those selectively affecting nouns (object names); (2) the impairment of a specific conceptual/semantic domain--we contrast disorders selectively affecting living beings with those preferentially affecting man-made artefacts. The hypothesis that different categories of knowledge may be closely intertwined with different sources of sensory-motor information, was substantially confirmed. The lesion preferentially encroached on the left frontal lobe when the category "verbs" was selectively affected; it involved the left temporal lobe and the posterior association areas when the category "nouns" was preferentially disrupted; it involved bilateral temporo-limbic structures and inferior temporal lobes when the category "living beings" was selectively disrupted; it usually encroached on the left fronto-parietal areas when man-made artefacts and body parts were preferentially affected. These data support the hypothesis that: (a) action schemata may critically contribute to the development of the semantic representation of verbs, (b) mechanisms of sensory integration may play an important role in establishing the semantic representation of nouns; (c) high-level visual processing and multi-modal sensory convergency may critically contribute to organising the semantic representation of living beings; (d) motor-kinaesthetic integration may play a leading role in developing the semantic representation of man-made artefacts.

Auditory verbal hallucinations (AVHs) have a high prevalence in schizophrenic patients. An array of studies have explored the neural correlates of AVHs by means of functional neuroimaging and have associated AVHs with diverse brain regions, some of which have been shown to be involved in speech generation, speech perception, and auditory stimulus processing. We divided these studies into "state" studies comparing periods of presence and absence of AVHs within-subject and "trait" studies comparing patients experiencing AVHs with patients without AVHs or healthy controls during tasks, with verbal material. We set out to test the internal consistency and possible dissociations of the neural correlates of AVHs. We used activation likelihood estimation to perform quantitative meta-analyses on brain regions reported in state and trait studies on AVHs to assess significant concordance across studies. State studies were associated with activation in bilateral inferior frontal gyrus, bilateral postcentral gyrus, and left parietal operculum. Trait studies on the other hand showed convergence of decreases in hallucinating subjects in left superior temporal gyrus, left middle temporal gyrus, anterior cingulate cortex, and left premotor cortex activity. Based on the clear dissociation of brain regions that show convergence across state in comparison to trait studies, we conclude that the state of experiencing AVHs is primarily related brain regions that have been implicated in speech production ie, Broca's area, whereas the general trait that makes humans prone to AVHs seems to be related to brain areas involved in auditory stimuli processing and speech perception, ie, auditory cortex.

The role of Broca's area in sentence processing remains controversial. According to one view, Broca's area is involved in processing a subcomponent of syntactic processing. Another view holds that it contributes to sentence processing via verbal working memory. Sub-regions of Broca's area have been identified that are more active during the processing of complex (object-relative clause) sentences compared to simple (subject-relative clause) sentences. The present study aimed to determine if this complexity effect can be accounted for in terms of the articulatory rehearsal component of verbal working memory. In a behavioral experiment, subjects were asked to comprehend sentences during concurrent speech articulation which minimizes articulatory rehearsal as a resource for sentence comprehension. A finger-tapping task was used as a control concurrent task. Only the object-relative clause sentences were more difficult to comprehend during speech articulation than during the manual task, showing that articulatory rehearsal does contribute to sentence processing. A second experiment used fMRI to document the brain regions underlying this effect. Subjects judged the plausibility of sentences during speech articulation, a finger-tapping task, or without a concurrent task. In the absence of a secondary task, Broca's area (pars triangularis and pars opercularis) demonstrated an increase in activity as a function of syntactic complexity. However, during concurrent speech articulation (but not finger-tapping) this complexity effect was eliminated in the pars opercularis suggesting that this region supports sentence comprehension via its role in articulatory rehearsal. Activity in the pars triangularis was modulated by the finger-tapping task, but not the speech articulation task.

Transcranial direct current stimulation (tDCS) has been proposed as an adjuvant technique to improve functional recovery after ischaemic stroke. This study evaluated the effect of tDCS over the left frontotemporal areas in eight chronic non-fluent post-stroke aphasic patients. The protocol consisted of the assessment of picture naming (accuracy and response time) before and immediately after anodal or cathodal tDCS (2 mA, 10 minutes) and sham stimulation. Whereas anodal tDCS and sham tDCS failed to induce any changes, cathodal tDCS significantly improved the accuracy of the picture naming task by a mean of 33.6% (SEM 13.8%).

Schizophrenia is postulated to be the prototypical dysconnection disorder, in which hallucinations are the core symptom. Due to high heterogeneity in methodology across studies and the clinical phenotype, it remains unclear whether the structural brain dysconnection is global or focal and if clinical symptoms result from this dysconnection. In the present work, we attempt to clarify this issue by studying a population considered as a homogeneous genetic sub-type of schizophrenia, namely the 22q11.2 deletion syndrome (22q11.2DS). Cerebral MRIs were acquired for 46 patients and 48 age and gender matched controls (aged 6 to 26, respectively mean age = 15.20 ± 4.53 and 15.28 ± 4.35 years old). Using the Connectome mapper pipeline (connectomics.org) that combines structural and diffusion MRI, we created a whole brain network for each individual. The graph theory was used to quantify the global and local properties in the brain network organization for each participant. A global degree loss of 6% was found in patients’ network along with an increased Characteristic Path Length. After identifying and comparing hubs, a significant loss of degree in patients’ hubs was found in 58% of them. Based on Allen’s brain network model for hallucinations, we explored the association between local efficiency and symptom severity. Negative correlations were found in the Broca’s area (p

The ability of aphasic patients to draw from memory objects with a characteristic shape has been investigated. Their capacity to reproduce the form of real objects was studied by showing them for a short time line drawings of simple objects. When the patient had analysed and recognized the figure, the model was hidden from view and the subject was asked to draw the same object from memory. This Drawing from Memory task was administered to 54 aphasics, 67 patients with right hemisphere lesions, 44 nonaphasic left brain-damaged patients and 23 normal controls. The influence of visuoconstructive disabilities was controlled by administering to the same patients a standard test for constructional apraxia (copying 10 geometrical figures). The severity and clinical form of the aphasia and the presence of semantic-lexical impairment at the receptive level were also examined in the aphasic patients. The following results were obtained. (1) Aphasic patients scored significantly less well than the control groups on the Drawing from Memory task and the intergroup differences became greater when the scores from the test for constructional apraxia were included by an analysis of covariance. (2) No significant correlation was detected between the severity and clinical form of the aphasia and the scores obtained on the Drawing from Memory task. (3) There was a significant correlation between impaired drawing from memory and disruption at the semantic-lexical level of language integration.

A nonverbal test of conceptual thinking was administered to 55 normal controls and to 203 patients with monohemispheric brain lesions (74 aphasics and 129 nonaphasic brain-damaged patients), in order to study the relationships between conceptual impairment of aphasic patients and breakdown of the semantic-lexical level of integration of language. A very high number of aphasic patients (54 out of 74) and a limited number of nonaphasic brain-damaged subjects (31 out of 129) obtained a pathological score on the test of conceptual thinking, but only some components of the aphasic symptomatology seemed closely linked to the conceptual disorder. In fact a non-significant relationship was found between conceptual impairment and: ("fluent" or "non-fluent") clinical type of aphasia; severity of aphasic disturbance. On the contrary, a strong relationship was found between conceptual disorder and impairment of the semantic-lexical level of integration of language. These findings seem to show that conceptual disturbance and semantic-lexical troubles are closely linked in aphasia.

A deep dyslexic patient was tested on a series of experiments designed to assess her comprehension of abstract words. On tests where a precise semantic representation of words was required, performance was much poorer with visual than with auditory presentation. However, on some but not all categorisation tests performance with both modalities was good. It is argued that deep dyslexia can result from a modality-specific deficit in attaining the meaning of words together with a disorder of the phonological reading route.

The present research was carried out to determine whether Jakobson's claim that Broca's aphasic patients emit chiefly semantic paraphasias of the similarity type, whereas Wernicke's aphasic patients produce mainly paraphasic substitutions of the contiguity type, can be supported by data gathered for clinical purposes under controlled conditions. Semantic paraphasias produced by 96 aphasic patients on a standard test of visual naming were taken into account. Three independent judges, blind to aphasia type, classified all responses retained as semantic substitutions into one of the following four categories: those having 1) a strong similarity, 2) a strong contiguity, 3) a mild similarity, and 4) a mild contiguity relation to the correct word. No relationship was found between type of semantic paraphasias and clinical form of aphasia. Furthermore, irrespective of the clinical form of aphasia, aphasics tend to give more similarity substitutions than contiguity substitutions.

The influence of sex, age, educational level and pathologic lesion on incidence, severity and clinical form of aphasia was investigated in 390 right-handed, left brain-damaged patients. Sex and educational level were not related to any parameter. Etiology of lesion and age were related to both incidence and type of aphasia. Incidence of aphasia increased with age and was higher in patients with cerebrovascular accidents than in subjects with other types of brain lesions. Non-fluent forms of aphasia were more frequent in young patients suffering from acute cerebrovascular accidents, whereas anomia prevailed in neoplastic subjects and Wernicke's aphasia increased regularly in frequency with age. Some tentative explanations of these findings are discussed.