Enhancing Speech Rehabilitation in a Young Adult with Trisomy 21: Integrating Transcranial Direct Current Stimulation (tDCS) with Rapid Syllable Transition Training for Apraxia of Speech.

Apraxia of speech is a persistent speech motor disorder that affects speech intelligibility. Studies on speech motor disorders with transcranial Direct Current Stimulation (tDCS) have been mostly directed toward examining post-stroke aphasia. Only a few tDCS studies have focused on apraxia of speech or childhood apraxia of speech (CAS), and no study has investigated individuals with CAS and Trisomy 21 (T21, Down syndrome). This N-of-1 randomized trial examined the effects of tDCS combined with a motor learning task in developmental apraxia of speech co-existing with T21 (ReBEC RBR-5435x9). The accuracy of speech sound production of nonsense words (NSWs) during Rapid Syllable Transition Training (ReST) over 10 sessions of anodal tDCS (1.5 mA, 25 cm) over Broca's area with the cathode over the contralateral region was compared to 10 sessions of sham-tDCS and four control sessions in a 20-year-old male individual with T21 presenting moderate-severe childhood apraxia of speech (CAS). The accuracy for NSW production progressively improved (gain of 40%) under tDCS (sham-tDCS and control sessions showed < 20% gain). A decrease in speech severity from moderate-severe to mild-moderate indicated transfer effects in speech production. Speech accuracy under tDCS was correlated with Wernicke's area activation (P3 current source density), which in turn was correlated with the activation of the left supramarginal gyrus and the Sylvian parietal-temporal junction. Repetitive bihemispheric tDCS paired with ReST may have facilitated speech sound acquisition in a young adult with T21 and CAS, possibly through activating brain regions required for phonological working memory.

El Área del Lenguaje Articulado, Perspectiva Histórica y Denominación Epónima Equívoca: Entre Dax y Broca / Articulated Language Area, Historical Perspective and Erroneous Epomy: Between Dax and Broca

El término epónimo área de Broca corresponde a una región cortical cerebral humana dedicada a la expresión del lenguaje oral y que no siempre se ubica en el giro frontal inferior del lobo frontal en el hemisferio izquierdo. Al estudiar 25 artículos del año 2022 y 25 libros de enseñanza de la neuroanatomía, neurofisiología, neurociencia o áreas asociadas del presente siglo, se estableció y cuantificó la existencia del término área de Broca encontrándose que en los libros había un 96 % de inclusión epónima sobre esta área cortical cerebral y en artículos de revista existía un 100 % del mismo epónimo, además, en ninguno de los libros y artículos se encontró un epónimo diferente. Aunque a lo largo del tiempo, en las ciencias médicas se han usado epónimos para designar estructuras anatómicas como en el caso para tratar de designar el área del cerebro que genera el lenguaje oral, este término no proporciona ninguna información descriptiva ni funcional, lo que equivale a un desatino en la lógica del pensamiento morfológico actual, además que lleva a confusión, pues hace pensar que su descubrimiento inicial fue dado por Broca, equivocando el conocimiento histórico que vincula a Marc Dax como el primero en descubrir esta zona.

SUMMARY: The eponymous Broca's area is a human cerebral cortical region that controls the expression of oral language, and which is not always located in the inferior frontal gyrus of the frontal lobe in the left hemisphere. In a study of 25 articles published in 2022, and 25 teaching books on neuroanatomy, neurophysiology, neuroscience or associated areas, it was found that the term Broca's area was established and quantified. In books there was a 96 % eponymous inclusion of this cerebral cortical area and in journal articles there was 100 % of the same eponym. Furthermore, no other eponyms were found in any of the books and articles. Although over time, eponyms have been used in medical sciences to identify anatomical structures, as in the designation of the area in the brain that controls oral language, this term does not provide any descriptive or functional information. The result is contradictory to current morphological thought and also leads to confusion, erroneously suggesting that the initial discovery was made by Broca, when in fact Marc Dax was the first to discover this area some 30 years earlier.

White Matter Microstructural Abnormalities in the Broca's-Wernicke's-Putamen "Hoffman Hallucination Circuit" and Auditory Transcallosal Fibers in First-Episode Psychosis With Auditory Hallucinations.

BACKGROUND: Functional connectivity abnormalities between Broca's and Wernicke's areas and the putamen revealed by functional magnetic resonance imaging (fMRI) are related to auditory hallucinations (AH). In long-term schizophrenia, reduced white matter structural integrity revealed by diffusion imaging in left arcuate fasciculus (connecting Broca's and Wernicke's areas) is likely related to AH. The structural integrity of connections with putamen and their relation to AH are unknown. Little is known about this relationship in first-episode psychosis (FEP), although auditory transcallosal connections were reported to play a role. White matter in the Broca's-Wernicke's-putamen language-related circuit and auditory transcallosal fibers was examined to investigate associations with AH in FEP. METHODS: White matter connectivity was measured in 40 FEP and 32 matched HC using generalized fractional anisotropy (gFA) derived from diffusion spectrum imaging (DSI). RESULTS: FEP and HC did not differ in gFA in any fiber bundle. In FEP, AH severity was significantly inversely related to gFA in auditory transcallosal fibers and left arcuate fasciculus. Although the right hemisphere arcuate fasciculus-AH association did not attain significance, the left and right arcuate fasciculus associations were not significantly different. CONCLUSIONS: Despite overall normal gFA in FEP, AH severity was significantly related to gFA in transcallosal auditory fibers and the left hemisphere connection between Broca's and Wernicke's areas. Other bilateral tracts' gFA were weakly associated with AH. At the first psychotic episode, AH are more robustly associated with left hemisphere arcuate fasciculus and interhemispheric auditory fibers microstructural deficits, likely reflecting mistiming of information flow between language-related cortical centers.

What are the barriers to participation in a neuromodulation pilot trial for aphasia after stroke? / Quais são as barreiras para a participação em estudo piloto de neuromodulação para afasia após acidente vascular cerebral?

ABSTRACT Purpose Aphasia is a common and debilitating manifestation of stroke. Transcranial electrical stimulation uses low-intensity electric currents to induce changes in neuronal activity. Recent evidence suggests that noninvasive techniques can be a valuable rehabilitation tool for patients with aphasia. However, it is difficult to recruit patients with aphasia for trials, and the reasons for this are not well understood. This study aimed to elucidate the main difficulties involved in patient's recruitment and inclusion in a randomized clinical study of neuromodulation in aphasia. Methods We evaluated the reasons for the exclusion of patients in a pilot, randomized, double-blinded clinical trial in which patients diagnosed with motor aphasia after stroke were recruited from March to November 2018. A descriptive statistical analysis was performed. Results Only 12.9% (4) of patients with ischemic stroke were included in the clinical trial. A total of 87.1% (27) of the 31 recruited patients were excluded for various reasons including: sensory aphasia (32.2%), dysarthria (25.8%), spontaneous clinical recovery (16.1%), previous stroke (6.4%), and death or mutism (3.2%). Conclusion The presence of other types of aphasia, dysarthria, spontaneous recovery, deaths, and mutism were barriers to recruiting patients evidenced in this neuromodulation study.

RESUMO Objetivo A afasia é uma manifestação comum e debilitante do acidente vascular cerebral (AVC). A estimulação elétrica transcraniana por corrente contínua oferece uma corrente elétrica de baixa intensidade que induz alterações na atividade neuronal e evidências recentes sugerem que técnicas não invasivas podem servir como uma ferramenta benéfica para a reabilitação de pacientes afásicos. No entanto, é muito difícil recrutar esses pacientes para estudos clínicos e as razões não são claras. O objetivo do estudo foi identificar as principais dificuldades envolvidas no recrutamento e inclusão de pacientes em ensaio clínico piloto randomizado sobre neuromodulação em pacientes com afasia. Método Foram avaliadas as razões para a exclusão e não inclusão de pacientes em um ensaio clínico piloto, randomizado, duplo-cego no qual foram incluídos pacientes diagnosticados com afasia motora após AVC no período de março a novembro de 2018. Análise estatística descritiva foi realizada. Resultados Apenas 12,9% (4) dos pacientes com AVC isquêmico foram incluídos no estudo. Um total de 87,1% (27) dos 31 pacientes recrutados foram excluídos por apresentarem afasia sensorial (32,2%), disartria (25,8%), recuperação clínica espontânea (16,1%), AVC prévio (6,4%) e óbito ou mutismo (3,2%). Conclusão A presença de outros tipos de afasia, disartria, recuperação espontânea, óbitos e mutismo foram as principais barreiras ao recrutamento de pacientes evidenciadas nesse estudo de neuromodulação.

Effect of Anodal tDCS on Articulatory Accuracy, Word Production, and Syllable Repetition in Subjects with Aphasia: A Crossover, Double-Blinded, Sham-Controlled Trial.

INTRODUCTION: Transcranial direct-current stimulation (tDCS) has been used to modulate and induce changes in brain function and excitability. tDCS is a promising tool for the treatment of aphasia. OBJECTIVE: To evaluate whether tDCS improves articulatory accuracy and speech production in patients with aphasia after stroke. METHODS AND RESULTS: Twelve right-handed subjects participated in a double-blind, sham-controlled, crossover offline trial. We assessed (1) articulatory accuracy at a naming task, (2) number of words correctly produced, (3) number of syllables repeated correctly, and (4) qualitative assessment of speech. Articulatory accuracy improved when using tDCS over Broca's area in subjects with aphasia post-stroke (p ≤ 0.05). Qualitative improvement in the naming and syllable repetition tasks was observed, but the difference was not statistically significant (respectively, p = 0.15 and p = 0.79). CONCLUSION: The current results corroborate the potential of tDCS to be used as an alternative and complementary treatment for individuals with aphasia.

Beyond Broca's area: why undergraduate neuroscience education matters.

Patients with psychiatric illness often present a unique challenge to medical students: in contrast to some medical conditions, in which patients may seem to be stricken by a disease, patients with certain psychiatric illnesses may seem complicit with the illness. Questions of free will, choice, and the role of the physician can quickly become overwhelming. This may result in students feeling helpless, disinterested, or even resentful. Here we argue that integrating a modern neuroscience perspective into medical education allows students to conceptualize psychiatric patients in a way that promotes empathy and enhances patient care. Specifically, a strong grasp of neuroscience prevents the future physician from falling into dualistic thinking in which the psychosocial aspects of a patient's presentation are considered beyond the realm of medicine. The value of incorporating neuroscience into a full, biopsychosocial formulation is demonstrated with the case example of a "difficult patient."

Una revisión de la neuroanatomía y neurofisiología del lenguaje / A review of the neuroanatomy and neurophysiology of language

Este artículo de revisión intenta examinar las diferentes estructuras del sistema nervioso, tanto central como periférico, involucradas en el proceso del lenguaje. Tras cuestionar el modelo clásico que atribuye las funciones del lenguaje exclusivamente a las áreas de Broca y Wernicke, se presenta la hipótesis de que el lenguaje se basa en redes neuronales complejas interconectadas con áreas cognitivas. A punto de partida de la premisa de que todo estímulo es categorizable, es decir transformable y codificable en forma de lenguaje, se estipula que para una correcta interacción con el entorno y una comunicación lingüística fructífera, la coordinación, funcionamiento y comunicación entre diferentes estructuras neuroanatómicas son factores necesarios cuya descripción y explicación se presentan de manera sistemática.

The aim of this paper is to review the different structures of the nervous system, both central and peripheral, involved in the language process. The classical model in which language functions are attributed to and localized in the areas of Broca and Wernicke is questioned, and the hypothesis that language is based on interconnections of complex neural networks and cognitive areas, is presented. On the basis of the premise that every stimulus is categorizable, that is, transformable and codifiable in the form of language, it is stipulated that in order to reach a correct interaction with the surroundings and an effective linguistic communication, the coordination, functioning and communication between different neuroanatomical structures whose description and explanation are systematically presented, are much needed factors.

Gestures, vocalizations, and memory in language origins.

THIS ARTICLE DISCUSSES THE POSSIBLE HOMOLOGIES BETWEEN THE HUMAN LANGUAGE NETWORKS AND COMPARABLE AUDITORY PROJECTION SYSTEMS IN THE MACAQUE BRAIN, IN AN ATTEMPT TO RECONCILE TWO EXISTING VIEWS ON LANGUAGE EVOLUTION: one that emphasizes hand control and gestures, and the other that emphasizes auditory-vocal mechanisms. The capacity for language is based on relatively well defined neural substrates whose rudiments have been traced in the non-human primate brain. At its core, this circuit constitutes an auditory-vocal sensorimotor circuit with two main components, a "ventral pathway" connecting anterior auditory regions with anterior ventrolateral prefrontal areas, and a "dorsal pathway" connecting auditory areas with parietal areas and with posterior ventrolateral prefrontal areas via the arcuate fasciculus and the superior longitudinal fasciculus. In humans, the dorsal circuit is especially important for phonological processing and phonological working memory, capacities that are critical for language acquisition and for complex syntax processing. In the macaque, the homolog of the dorsal circuit overlaps with an inferior parietal-premotor network for hand and gesture selection that is under voluntary control, while vocalizations are largely fixed and involuntary. The recruitment of the dorsal component for vocalization behavior in the human lineage, together with a direct cortical control of the subcortical vocalizing system, are proposed to represent a fundamental innovation in human evolution, generating an inflection point that permitted the explosion of vocal language and human communication. In this context, vocal communication and gesturing have a common history in primate communication.

Broca's aphemia: an illustrated account of its clinico-anatomic validity

OBJECTIVE: To present the case of a 54-year-old man with loss of speech, but with preservation of voluntary facio-lingual motility, language and other cognitive abilities (Broca's aphemia). METHOD: Observation of patient oral communicative abilities and general behavior, neuropsychological assessment and cranial computed tomography. RESULTS: Computed tomography showed a hyperdense lesion in the subcortex of the left precentral gyrus corresponding to Brodmann's area 6 and 44. Neuropsychological assessment confirmed that the major cognitive domains were intact. CONCLUSION: Our patient reiterates the validity of Broca's aphemia as a clinico-anatomic entity allowing us to portray it for the first time in pictures. From a neurobehavioral perspective, aphemia is related to apraxia rather than to aphasia, a fact that may have hampered the full grasp of its far-reaching implications for neurology and aphasiology.

OBJETIVO: Apresentar o caso de um paciente de 54 anos de idade com perda da fala, mas preservação da linguagem, das demais capacidades cognitivas, e da motilidade fácio-lingual voluntária (afemia de Broca). MÉTODO: Observação da capacidade de comunicação oral e do comportamento geral, exame neuropsicológico e tomografia computadorizada do crânio. RESULTADOS: A tomografia computadorizada revelou lesão hiperdensa no subcórtex do giro precentral esquerdo correspondendo às áreas 6 e 44 de Brodmann. O exame neuropsicológico confirmou que os principais domínios cognitivos se encontravam intactos. CONCLUSÃO: Nosso paciente reiterou a validade da afemia de Broca como entidade anátomo-clínico permitindo documentá-la em fotos pela primeira vez. Da perspectiva neurocomportamental, a afemia está vinculada às apraxias e não às afasias, o que pode ter prejudicado a apreensão plena do seu profundo significado para a neurologia e para a afasiologia.