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1.
Sci Rep ; 10(1): 11968, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32747731

RESUMO

Human brains process lexical meaning separately from emotional prosody of speech at higher levels of the processing hierarchy. Recently we demonstrated that dog brains can also dissociate lexical and emotional prosodic information in human spoken words. To better understand the neural dynamics of lexical processing in the dog brain, here we used an event-related design, optimized for fMRI adaptation analyses on multiple time scales. We investigated repetition effects in dogs' neural (BOLD) responses to lexically marked (praise) words and to lexically unmarked (neutral) words, in praising and neutral prosody. We identified temporally and anatomically distinct adaptation patterns. In a subcortical auditory region, we found both short- and long-term fMRI adaptation for emotional prosody, but not for lexical markedness. In multiple cortical auditory regions, we found long-term fMRI adaptation for lexically marked compared to unmarked words. This lexical adaptation showed right-hemisphere bias and was age-modulated in a near-primary auditory region and was independent of prosody in a secondary auditory region. Word representations in dogs' auditory cortex thus contain more than just the emotional prosody they are typically associated with. These findings demonstrate multilevel fMRI adaptation effects in the dog brain and are consistent with a hierarchical account of spoken word processing.


Assuntos
Córtex Auditivo/fisiologia , Mapeamento Encefálico/veterinária , Cães/fisiologia , Imagem por Ressonância Magnética/veterinária , Fala , Animais , Percepção Auditiva , Mapeamento Encefálico/métodos , Dominância Cerebral , Emoções , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Vigília
2.
Neurology ; 95(6): e637-e642, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32636329

RESUMO

OBJECTIVE: To study neural networks involved in hyperkinetic seizures (HKS) using ictal SPECT. METHODS: We retrospectively identified 18 patients with HKS evaluated at the Cleveland Clinic between 2005 and 2015 with video-EEG monitoring and ictal SPECT. Semiology was confirmed by the consensus of 2 epileptologists' independent reviews and classified as type 1, 2, or 3 HKS. SPECT data were analyzed by 2 independent physicians using a z score of 1.5. Ictal hyperperfusion patterns for each group were analyzed visually and with SPM. Spatial normalization to Montreal Neurological Institute space for each patient's data was performed, followed by flipping of data from patients with left-sided ictal onset to the right side. Finally, an average z score map for each group was calculated. RESULTS: Visual analysis and SPM identified different patterns of ictal hyperperfusion in the 3 subtypes of HKS. Type 1 seizures showed hyperperfusion in a more anteriorly located network involving the anterior insula, orbitofrontal cortex, cingulate, and anterior perisylvian region and rostral midbrain. Type 2 seizures were associated with hyperperfusion in a more caudally located network involving the orbitofrontal cortex, cingulate (middle and posterior), basal ganglia, thalami, and cerebellum. Type 3 seizures showed a mixed pattern of SPECT hyperperfusion involving the temporal pole and anterior perisylvian region. CONCLUSIONS: Each of the 3 different semiologic subtypes of HKS is associated with distinct patterns of hyperperfusion, providing further insight into the neural networks involved. This knowledge may inform placement of invasive EEG electrodes in patients with HKS semiology undergoing presurgical evaluation.


Assuntos
Epilepsia Motora Parcial/diagnóstico por imagem , Hipercinese/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Mapeamento Encefálico , Circulação Cerebrovascular , Criança , Dominância Cerebral , Eletroencefalografia/métodos , Epilepsia Motora Parcial/classificação , Epilepsia Motora Parcial/fisiopatologia , Feminino , Humanos , Hipercinese/fisiopatologia , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Cuidados Pré-Operatórios , Estudos Retrospectivos , Gravação em Vídeo/métodos , Adulto Jovem
3.
Occup Ther Int ; 2020: 2387378, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32565757

RESUMO

Objectives: Spontaneous arm use in patients with poststroke hemiparesis is crucial to the recovery of functional interaction. Patients with stroke and subsequent right hemiparesis have more difficulty adapting to a right-handed environment. The aim of this study was to use wearable devices to assess the asymmetry and difference in the amount of activity of the nondominant and dominant affected hands among patients with stroke and right hemiparesis. The real activity of both hands was measured to assess the correlation with various aspects of the International Classification of Functioning, Disability and Health (ICF). Subjects and Methods. Patients with stroke and right hemiparesis were recruited. They were divided into two groups according to the affected hand. Groups A and B comprised patients with affected nondominant and dominant hands, respectively. The Fugl-Meyer assessment-Upper Extremity (FM-UE) scores, Motor Activity Log (MAL), and hand function domain scores on the Stroke Impact Scale (SIS) were used for assessment. Patients were asked to wear smart wearable devices on both hands 24 hours a day for a month. The amount of activity in both hands was recorded and analyzed. Results: A total of 29 patients with stroke were divided into group A (n = 14) and group B (n = 15). FM-UE scores were significantly and strongly correlated with the amount of use (AOU) in the MAL. The recorded differential real activity of both hands in group B was significantly lower than that in group A. The asymmetry index of hand use was significantly less favorable in group B. However, no significant differences in AOU in the MAL, FM-UE, and hand function domain in the SIS were identified between the nondominant and dominant affected hands. Conclusions: The asymmetry and differential activity of both hands were worse in the patients with poststroke right hemiparesis, whose dominant hand was affected. However, no differences of three aspects of the ICF were found between dominant and nondominant affected hands.


Assuntos
Avaliação da Deficiência , Dominância Cerebral , Mãos/fisiopatologia , Paresia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Ocupacional , Paresia/etiologia , Paresia/reabilitação , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral , Extremidade Superior/fisiopatologia , Dispositivos Eletrônicos Vestíveis
4.
BMC Neurol ; 20(1): 120, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252685

RESUMO

BACKGROUND: Anomalies of pyramidal tract decussation are rare phenomena that can be caused by ectodermal dysplasia. Herein, we describe a patient with ichthyosis who exhibited ipsilateral hemiparesis after stroke and whose neuroimaging results showed evidence of motor control being provided by the ipsilateral motor cortex. CASE PRESENTATION: A 24-year-old right-handed man presented with skin abnormalities, sudden-onset left hemiparesis, and dysarthria. He exhibited a mild-to-moderate left-sided weakness (grade 4 on the Medical Research Council scale). Magnetic resonance imaging revealed an acute infarct in the left corona radiata. Diffusion tensor imaging revealed uncrossed corticospinal tracts. Next-generation sequencing identified heterozygous FLG mutations. The patient was diagnosed with cerebral infarction and ichthyosis vulgaris and was treated with aspirin (100 mg/d). His symptoms gradually dissipated. CONCLUSIONS: This case suggests that pyramidal decussation anomalies can be associated with ichthyosis. Patients with ichthyosis should therefore be evaluated for nerve involvement.


Assuntos
Ictiose/complicações , Ictiose/patologia , Paresia/complicações , Paresia/patologia , Tratos Piramidais/patologia , Acidente Vascular Cerebral/patologia , Imagem de Tensor de Difusão , Dominância Cerebral , Humanos , Masculino , Acidente Vascular Cerebral/complicações , Adulto Jovem
5.
Epileptic Disord ; 22(2): 207-213, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32301728

RESUMO

Despite advancements in the neurophysiology of language and presurgical evaluation for epilepsy surgery, there is a paucity of information in the literature regarding presurgical evaluation of multilingual patients. We present a case of a 52-year-old right-handed woman with refractory epilepsy who was fluent in six languages and underwent subsequent trilingual presurgical evaluation which included neuropsychological testing, Wada testing, functional magnetic resonance imaging (fMRI), and electrocortical stimulation. These studies suggested a seizure focus in the left temporal lobe and language localization that was predominantly right-hemispheric; she subsequently underwent left temporal laser interstitial thermal therapy without clinical disturbance in language function while remaining seizure-free. A multidisciplinary effort was integral in providing an optimal outcome for this patient.


Assuntos
Mapeamento Encefálico , Dominância Cerebral/fisiologia , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia do Lobo Temporal/diagnóstico , Multilinguismo , Epilepsia Resistente a Medicamentos/cirurgia , Estimulação Elétrica , Eletrocorticografia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Terapia a Laser , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Cuidados Pré-Operatórios
6.
Ann N Y Acad Sci ; 1477(1): 34-43, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32266985

RESUMO

Different species show an intriguing similarity in representing numerosity in space, starting from left to right. This bias has been attributed to a right hemisphere dominance in processing spatial information. Here, to disentangle the role of each hemisphere in dealing with spatial versus ordinal-numerical information, we tested domestic chicks during monocular versus binocular vision. In the avian brain, the contralateral hemisphere mainly processes the visual input from each eye. Four-day-old chicks learned to peck at the fourth element in a sagittal series of 10 identical elements. At testing, chicks faced a left-to-right-oriented series where the interelement distance was manipulated so that the third element was where the fourth had been at training; this compelled chicks to use either spatial or ordinal cues. Chicks tested binocularly selected both the fourth left and (to a lesser extent) right elements. Chicks tested monocularly chose the third and fourth elements on the seeing side equally. Interhemispheric cooperation resulted in the use of ordinal-numerical information, while each single hemisphere could rely on spatial or ordinal-numerical cue. Both hemispheres can process spatial and ordinal-numerical information, but their interaction results in the supremacy of processing the ordinal-numerical cue.


Assuntos
Cognição/fisiologia , Dominância Cerebral/fisiologia , Percepção Espacial/fisiologia , Animais , Galinhas/fisiologia , Lateralidade Funcional/fisiologia
7.
Development ; 147(6)2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32179574

RESUMO

Precise temporal coordination of signaling processes is pivotal for cellular differentiation during embryonic development. A vast number of secreted molecules are produced and released by cells and tissues, and travel in the extracellular space. Whether they induce a signaling pathway and instruct cell fate, however, depends on a complex network of regulatory mechanisms, which are often not well understood. The conserved bilateral left-right asymmetrically formed habenulae of the zebrafish are an excellent model for investigating how signaling control facilitates the generation of defined neuronal populations. Wnt signaling is required for habenular neuron type specification, asymmetry and axonal connectivity. The temporal regulation of this pathway and the players involved have, however, have remained unclear. We find that tightly regulated temporal restriction of Wnt signaling activity in habenular precursor cells is crucial for the diversity and asymmetry of habenular neuron populations. We suggest a feedback mechanism whereby the tumor suppressor Wnt inhibitory factor Wif1 controls the Wnt dynamics in the environment of habenular precursor cells. This mechanism might be common to other cell types, including tumor cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Padronização Corporal/genética , Habenula/embriologia , Neurogênese/genética , Neurônios/fisiologia , Proteínas Repressoras/fisiologia , Via de Sinalização Wnt/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Animais Geneticamente Modificados , Encéfalo/citologia , Encéfalo/embriologia , Diferenciação Celular/genética , Linhagem da Célula/genética , Dominância Cerebral/genética , Embrião não Mamífero , Habenula/metabolismo , Neurogênese/fisiologia , Neurônios/citologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
8.
Acta Psychol (Amst) ; 205: 103019, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32145463

RESUMO

The cognitive processing of spatial relations in Euclidean diagrams is central to the diagram-based geometric practice of Euclid's Elements. In this study, we investigate this processing through two dichotomies among spatial relations-metric vs topological and exact vs co-exact-introduced by Manders in his seminal epistemological analysis of Euclid's geometric practice. To this end, we carried out a two-part experiment where participants were asked to judge spatial relations in Euclidean diagrams in a visual half field task design. In the first part, we tested whether the processing of metric vs topological relations yielded the same hemispheric specialization as the processing of coordinate vs categorical relations. In the second part, we investigated the specific performance patterns for the processing of five pairs of exact/co-exact relations, where stimuli for the co-exact relations were divided into three categories depending on their distance from the exact case. Regarding the processing of metric vs topological relations, hemispheric differences were found for only a few of the stimuli used, which may indicate that other processing mechanisms might be at play. Regarding the processing of exact vs co-exact relations, results show that the level of agreement among participants in judging co-exact relations decreases with the distance from the exact case, and this for the five pairs of exact/co-exact relations tested. The philosophical implications of these empirical findings for the epistemological analysis of Euclid's diagram-based geometric practice are spelled out and discussed.


Assuntos
Cognição , Dominância Cerebral , Percepção Espacial , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Análise e Desempenho de Tarefas , Campos Visuais , Adulto Jovem
9.
Sci Rep ; 10(1): 5283, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32210267

RESUMO

The cerebellum is connected to numerous regions of the contralateral side of the cerebrum. Motor and cognitive deficits following neonatal cerebellar hemorrhages (CbH) in extremely preterm neonates may be related to remote cortical alterations, following disrupted cerebello-cerebral connectivity as was previously shown within six CbH infants. In this retrospective case series study, we used MRI and advanced surface-based analyses to reconstruct gray matter (GM) changes in cortical thickness and cortical surface area in extremely preterm neonates (median age = 26; range: 24.9-26.7 gestational weeks) with large isolated unilateral CbH (N = 5 patients). Each CbH infant was matched with their own preterm infant cohort (range: 20-36 infants) based on sex and gestational age at birth. On a macro level, our data revealed that the contralateral cerebral hemisphere of CbH neonates did not show less cortical thickness or cortical surface area than their ipsilateral cerebral hemisphere at term. None of the cases differed from their matched cohort groups in average cortical thickness or average cortical surface area in the ipsilateral or contralateral cerebral hemisphere. On a micro (i.e. vertex) level, we established high variability in significant local cortical GM alteration patterns across case-cohort groups, in which the cases showed thicker or bigger volume in some regions, among which the caudal middle frontal gyrus, insula and parahippocampal gyrus, and thinner or less volume in other regions, among which the cuneus, precuneus and supratentorial gyrus. This study highlights that cerebellar injury during postnatal stages may have  widespread bilateral influence on the early maturation of cerebral cortical regions, which implicate complex cerebello-cerebral interactions to be present at term birth.


Assuntos
Dano Encefálico Crônico/patologia , Córtex Cerebral/patologia , Substância Cinzenta/patologia , Doenças do Prematuro/patologia , Hemorragias Intracranianas/patologia , Dano Encefálico Crônico/diagnóstico por imagem , Dano Encefálico Crônico/etiologia , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Dominância Cerebral , Feminino , Idade Gestacional , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Recém-Nascido , Recém-Nascido Prematuro , Hemorragias Intracranianas/complicações , Hemorragias Intracranianas/diagnóstico por imagem , Imagem por Ressonância Magnética , Masculino , Neuroimagem , Estudos Retrospectivos
10.
J Neurol Surg A Cent Eur Neurosurg ; 81(2): 147-154, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32045942

RESUMO

OBJECTIVE: Neuronavigated repetitive transcranial stimulation (rTMS) at a frequency of 1 Hz was shown to reduce excitability in underlying brain areas while increasing excitability in the opposite hemisphere. In stroke patients, this principle is used to normalize activity between the lesioned and healthy hemispheres and to facilitate rehabilitation. However, standardization is lacking in applied protocols, and there is a poor understanding of the underlying physiologic mechanisms. Furthermore, the influence of hemispheric dominance on the intervention has not been studied before. A systematic evaluation of the effects in healthy subjects would deepen the understanding of these mechanisms and offer insights into ways to improve the intervention. METHODS: Twenty healthy subjects underwent five 15-minute sessions of neuronavigated rTMS or sham stimulation over their dominant or nondominant motor cortex. Dominance was assessed with the Edinburgh Handedness Inventory. Changes in both hemispheres were measured using behavioral parameters (finger tapping, grip force, and finger dexterity) and TMS measures (resting motor threshold, recruitment curve, motor area, and cortical silent period). RESULTS: All subjects tolerated the stimulation well. A pronounced improvement was noted in finger tapping scores over the nonstimulated hemisphere as well as a nonsignificant reduction of the cortical silent period in the stimulated hemisphere, indicating a differential effect of the rTMS on both hemispheres. Grip force remained at the baseline level in the rTMS group while decreasing in the sham group, suggesting the rTMS counterbalanced the effects of fatigue. Lastly, dominance did not influence any of the observed effects. CONCLUSIONS: This study shows the capability of the applied low-frequency rTMS protocol to modify excitability of underlying brain areas as well as the contralateral hemisphere. It also highlights the need for a better understanding of underlying mechanisms and the identification of predictors for responsiveness to rTMS. However, results should be interpreted with caution because of the small sample size.


Assuntos
Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Mapeamento Encefálico , Dominância Cerebral , Feminino , Dedos , Força da Mão/fisiologia , Voluntários Saudáveis , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Destreza Motora , Neuronavegação , Recrutamento Neurofisiológico , Método Simples-Cego , Estimulação Magnética Transcraniana/efeitos adversos , Adulto Jovem
11.
J Neurol Surg A Cent Eur Neurosurg ; 81(2): 130-137, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32045945

RESUMO

BACKGROUND AND STUDY AIMS: Language mapping by navigated transcranial magnetic stimulation (TMS) is commonly applied over the left language-dominant hemisphere to indicate the language-related cortex. Detailed language mapping of Broca's region including stimulation targets in the immediate vicinity to the premotor cortex may raise concern about confounding unspecific motor effects. We performed interhemispheric comparisons to delineate such possible unspecific effects from true TMS-induced language inhibition. MATERIAL AND METHODS: Fifteen healthy German speakers named object pictures during navigated TMS over a left- and right-hemispheric target array covering the left inferior frontal junction area. Six mapping repetitions were conducted per hemisphere. Order of stimulation side was randomized between participants. Self-rating of discomfort was assessed after each stimulation; language errors and motor side effects were evaluated offline. RESULTS: Naming errors were observed significantly more frequently during left- than right-hemispheric stimulation. The same pattern was found for the most frequent error category of performance errors. Hierarchical cluster analyses of normalized ratings of error severity revealed a clear focus of TMS susceptibility for language inhibition in object naming at the dorsoposterior target sites only in the left hemisphere. We found no statistical difference in discomfort ratings between both hemispheres and also no interhemispheric difference in motor side effects, but we observed significantly stronger muscle contractions of the eyes as compared with the mouth. CONCLUSION: Our results of (1) unspecific pre-/motor effects similarly induced in both hemispheres, and (2) a specific focus of TMS susceptibility in the language-dominant hemisphere render any substantial contribution of nonlanguage-specific effects in TMS language mapping of the inferior frontal junction area highly unlikely.


Assuntos
Mapeamento Encefálico/métodos , Dominância Cerebral , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiologia , Idioma , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Masculino , Transtornos dos Movimentos/etiologia , Contração Muscular , Neuronavegação , Músculos Oculomotores/fisiologia , Conforto do Paciente , Desempenho Psicomotor , Estimulação Magnética Transcraniana/efeitos adversos , Adulto Jovem
12.
Crit Care Nurs Clin North Am ; 32(1): 1-19, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32014156

RESUMO

Acute stroke assessment is classically supported by clinical localization whereby presenting disabilities are associated with key arterial territories in the brain. Clinical localization skills are rarely taught to nonneurologists; yet, these skills are essential to the provision of evidence-based nursing care of stroke, enabling rapid patient identification, diagnosis, and ultimately, the delivery of acute treatment. This article explores the process of clinical localization in relation to the physiology affected by stroke vascular insufficiency. Elements of the neurologic examination are described as they relate to discreet areas in the brain and the National Institutes of Health Stroke Scale.


Assuntos
Encéfalo/patologia , Dominância Cerebral/fisiologia , Exame Neurológico , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Artérias Cerebrais/patologia , Hemianopsia , Hemiplegia , Humanos , Enfermagem em Neurociência , Índice de Gravidade de Doença , Acidente Vascular Cerebral/enfermagem , Estados Unidos
13.
Exp Brain Res ; 238(3): 727-739, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32080750

RESUMO

When asked to identify the position of a sound, listeners can report its perceived location as well as their subjective certainty about this spatial judgement. Yet, research to date focused primarily on measures of perceived location (e.g., accuracy and precision of pointing responses), neglecting instead the phenomenological experience of subjective spatial certainty. The present study aimed to investigate: (1) changes in subjective certainty about sound position induced by listening with one ear plugged (simulated monaural listening), compared to typical binaural listening and (2) the relation between subjective certainty about sound position and localisation accuracy. In two experiments (N = 20 each), participants localised single sounds delivered from one of 60 speakers hidden from view in front space. In each trial, they also provided a subjective rating of their spatial certainty about sound position. No feedback on response was provided. Overall, participants were mostly accurate and certain about sound position in binaural listening, whereas their accuracy and subjective certainty decreased in monaural listening. Interestingly, accuracy and certainty dissociated within single trials during monaural listening: in some trials participants were certain but incorrect, in others they were uncertain but correct. Furthermore, unlike accuracy, subjective certainty rapidly increased as a function of time during the monaural listening block. Finally, subjective certainty changed as a function of perceived location of the sound source. These novel findings reveal that listeners quickly update their subjective confidence on sound position, when they experience an altered listening condition, even in the absence of feedback. Furthermore, they document a dissociation between accuracy and subjective certainty when mapping auditory input to space.


Assuntos
Atenção/fisiologia , Vias Auditivas/fisiologia , Localização de Som/fisiologia , Adulto , Testes com Listas de Dissílabos/métodos , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
14.
Behav Processes ; 168: 103959, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31513830

RESUMO

Despite the abundant empirical evidence on lateralized social behaviours, a clear understanding of the relative roles of two brain hemispheres in social processing is still lacking. This study investigated visual lateralization in social interactions of free-ranging European bison (Bison bonasus). The bison were more likely to display aggressive responses (such as fight and side hit), when they viewed the conspecific with the right visual field, implicating the left brain hemisphere. In contrast, the responses associated with positive social interactions (female-to-calf bonding, calf-to-female approach, suckling) or aggression inhibition (fight termination) occurred more likely when the left visual field was in use, indicating the right hemisphere advantage. The results do not support either assumptions of right-hemisphere dominance for control of various social functions or hypotheses about simple positive (approach) versus negative (withdrawal) distinction between the hemispheric roles. The discrepancy between the studies suggests that in animals, the relative roles of the hemispheres in social processing may be determined by a fine balance of emotions and motivations associated with the particular social reaction difficult to categorize for a human investigator. Our findings highlight the involvement of both brain hemispheres in the control of social behaviour.


Assuntos
Bison/fisiologia , Dominância Cerebral/fisiologia , Relações Interpessoais , Meio Social , Percepção Visual/fisiologia , Agressão/fisiologia , Animais , Encéfalo/fisiologia , Emoções/fisiologia , Feminino , Humanos , Inibição Psicológica , Masculino , Motivação/fisiologia , Federação Russa , Comportamento Social , Campos Visuais/fisiologia
15.
World Neurosurg ; 132: e759-e765, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31415886

RESUMO

OBJECTIVE: To determine postoperative long-term changes of hippocampal volume (HV) correlating with cognitive functions in patients who underwent surgery for hippocampal sclerosis with postoperative freedom from seizures. METHODS: We studied 1.5T magnetic resonance imaging before and after surgery in 24 patients (mean ± SD age, 36.9 ± 11.0 years) with hippocampal sclerosis. We performed serial magnetic resonance imaging at 6 months to 1 year, 1-2 years, 2-3 years, and 3-5 years postoperatively. We compared HVs of 24 patients with HVs of 14 age-matched control subjects. We analyzed correlations between consecutive HVs and seizure duration and age at surgery. We compared consecutive changes in HVs between dominant and nondominant hemispheres with concurrent cognitive functions. RESULTS: Preoperative HVs of unresected contralateral hippocampus were significantly smaller than HVs of control subjects (P < 0.01). Unresected contralateral HV changes compared with preoperative HVs were -3.6% ± 6.9%, -2.3% ± 8.5%, -3.6% ± 10.2% (P < 0.05), and -5.0% ± 9.5% (P < 0.05) at consecutive postoperative periods. Largest change in HVs at 3-5 years was significantly correlated with older age at surgery (P < 0.05). Unresected contralateral dominant 14 HVs remained consistently smaller than nondominant 10 HVs up to 5 years with statistical significance (P < 0.05). Verbal memory was preserved in 14 patients with unresected contralateral smaller dominant hippocampus. CONCLUSIONS: In seizure-free patients after hippocampal sclerosis resection , unresected contralateral HV significantly declined with older age at surgery. Visual memory was preserved regardless of side and volume loss. Despite significantly reduced HVs, verbal memory was preserved with the unresected contralateral dominant hippocampus. Earlier surgical intervention may have lower potential risk for memory decline secondary to postoperative HV loss.


Assuntos
Hipocampo/patologia , Hipocampo/cirurgia , Transtornos da Memória/prevenção & controle , Transtornos da Memória/psicologia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/psicologia , Adolescente , Adulto , Fatores Etários , Lobectomia Temporal Anterior , Criança , Dominância Cerebral , Feminino , Seguimentos , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Esclerose , Convulsões , Resultado do Tratamento , Adulto Jovem
16.
Laterality ; 24(6): 707-739, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31399020

RESUMO

Several non-verbal perceptual and attentional processes have been linked with specialization of the right cerebral hemisphere. Given that most people have a left hemispheric specialization for language, it is tempting to assume that functions of these two classes of dominance are related. Unfortunately, such models of complementarity are notoriously hard to test. Here we suggest a method which compares frequency of a particular perceptual asymmetry with known frequencies of left hemispheric language dominance in right-handed and non-right handed groups. We illustrate this idea using the greyscales and colourscales tasks, chimeric faces, emotional dichotic listening, and a consonant-vowel dichotic listening task. Results show a substantial "breadth" of leftward bias on the right hemispheric tasks and rightward bias on verbal dichotic listening. Right handers and non-right handers did not differ in terms of proportions of people who were left biased for greyscales/colourscales. Support for reduced typical biases in non-right handers was found for chimeric faces and for CV dichotic listening. Results are discussed in terms of complementary theories of cerebral asymmetries, and how this type of method could be used to create a taxonomy of lateralized functions, each categorized as related to speech and language dominance, or not.


Assuntos
Dominância Cerebral/fisiologia , Lateralidade Funcional/fisiologia , Percepção/fisiologia , Adulto , Atenção/fisiologia , Testes com Listas de Dissílabos , Emoções , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Caracteres Sexuais , Fala/fisiologia , Percepção Visual , Adulto Jovem
17.
Med Hypotheses ; 131: 109315, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31443748

RESUMO

Each brain hemisphere is dominant for certain functions such as speech. The determination of speech laterality prior to surgery is of paramount importance for accurate risk prediction. In this study, we aimed to determine speech laterality via EEG signals by using noninvasive machine learning techniques. The retrospective study included 67 subjects aged 18-65 years who had no chronic diseases and were diagnosed as healthy based on EEG examination. The subjects comprised 35 right-hand dominant (speech center located in the left hemisphere) and 32 left-hand dominant individuals (speech center located in the right hemisphere). A spectrogram was created for each of the 18 EEG channels by using various Convolutional Neural Networks (CNN) architectures including VGG16, VGG19, ResNet, MobileNet, NasNet, and DenseNet. These architectures were used to extract features from the spectrograms. The extracted features were classified using Support Vector Machines (SVM) and the classification performances of the CNN models were evaluated using Area Under the Curve (AUC). Of all the CNN models used in the study, VGG16 had a higher AUC value (0.83 ±â€¯0.05) in the determination of speech laterality compared to all other models. The present study is a pioneer investigation into the determination of speech laterality via EEG signals with machine learning techniques, which, to our knowledge, has never been reported in the literature. Moreover, the classification results obtained in the study are promising and lead the way for subsequent studies though not practically feasible.


Assuntos
Aprendizado Profundo , Diagnóstico por Computador/métodos , Dominância Cerebral , Adolescente , Adulto , Idoso , Área Sob a Curva , Área de Broca/fisiologia , Eletroencefalografia/métodos , Feminino , Análise de Fourier , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Máquina de Vetores de Suporte , Área de Wernicke/fisiologia , Adulto Jovem
18.
Neuroradiology ; 61(10): 1181-1190, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31399852

RESUMO

PURPOSE: To investigate proliferative reorganization in the bilateral corticospinal tract (CST) and functional reorganization in the sensorimotor network (SMN) after internal capsule stroke, and to examine the significance of this reorganization. METHODS: We recruited 17 patients with first-onset acute stroke (16 male, 1 female, mean age 52 ± 10 years) and 17 age- and sex-matched healthy controls. We excluded patients aged < 18 or > 65 years and those with lesions outside the unilateral internal capsule. All subjects underwent diffusion tensor imaging and resting-state functional MRI on days 7, 30, and 90 from symptom onset. We measured fractional anisotropy (FA) in the CST, interhemispheric functional connectivity (FC) within the SMN, and pre-MRI clinical scores, including the National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI), and Fugl-Meyer (FM). Correlations among the changes in FA, FC, and clinical scores were analyzed. RESULTS: From day 7 to 90 after stroke, FA in the bilateral CST increased (ipsilesional side, Pinternal capsule = 0.009, Pcentrum semiovale = 0.001; contralesional side, Pinternal capsule = 0.006, Pcentrum semiovale = 0.017), as did FC (P < 0.05); NIHSS scores decreased (P < 0.05), while FM and BI progressively increased (P < 0.05). Increased FA in bilateral CST was negatively correlated with decreased NIHSS scores. Increased FA in only the ipsilesional side was positively correlated with increased FM. Increased FC was positively correlated only with increased BI. CONCLUSION: Proliferative reorganization in the CST and functional reorganization in the SMN support and promote neurological functional recovery after internal capsule infarction.


Assuntos
Infarto Encefálico/diagnóstico , Cápsula Interna/irrigação sanguínea , Imagem por Ressonância Magnética , Regeneração Nervosa/fisiologia , Exame Neurológico , Córtex Sensório-Motor/diagnóstico por imagem , Adulto , Idoso , Infarto Encefálico/fisiopatologia , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Recuperação de Função Fisiológica , Córtex Sensório-Motor/fisiopatologia
19.
Am J Psychiatry ; 176(12): 1039-1049, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352813

RESUMO

OBJECTIVE: Asymmetry is a subtle but pervasive aspect of the human brain, and it may be altered in several psychiatric conditions. MRI studies have shown subtle differences of brain anatomy between people with major depressive disorder and healthy control subjects, but few studies have specifically examined brain anatomical asymmetry in relation to this disorder, and results from those studies have remained inconclusive. At the functional level, some electroencephalography studies have indicated left fronto-cortical hypoactivity and right parietal hypoactivity in depressive disorders, so aspects of lateralized anatomy may also be affected. The authors used pooled individual-level data from data sets collected around the world to investigate differences in laterality in measures of cortical thickness, cortical surface area, and subcortical volume between individuals with major depression and healthy control subjects. METHODS: The authors investigated differences in the laterality of thickness and surface area measures of 34 cerebral cortical regions in 2,256 individuals with major depression and 3,504 control subjects from 31 separate data sets, and they investigated volume asymmetries of eight subcortical structures in 2,540 individuals with major depression and 4,230 control subjects from 32 data sets. T1-weighted MRI data were processed with a single protocol using FreeSurfer and the Desikan-Killiany atlas. The large sample size provided 80% power to detect effects of the order of Cohen's d=0.1. RESULTS: The largest effect size (Cohen's d) of major depression diagnosis was 0.085 for the thickness asymmetry of the superior temporal cortex, which was not significant after adjustment for multiple testing. Asymmetry measures were not significantly associated with medication use, acute compared with remitted status, first episode compared with recurrent status, or age at onset. CONCLUSIONS: Altered brain macro-anatomical asymmetry may be of little relevance to major depression etiology in most cases.


Assuntos
Encéfalo/anatomia & histologia , Transtorno Depressivo Maior/patologia , Adulto , Estudos de Casos e Controles , Bases de Dados Factuais/estatística & dados numéricos , Dominância Cerebral , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Metanálise como Assunto , Neuroimagem , Adulto Jovem
20.
Hum Brain Mapp ; 40(15): 4397-4416, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31291039

RESUMO

The dopaminergic system has a unique gating function in the initiation and execution of movements. When the interhemispheric imbalance of dopamine inherent to the healthy brain is disrupted, as in Parkinson's disease (PD), compensatory mechanisms act to stave off behavioral changes. It has been proposed that two such compensatory mechanisms may be (a) a decrease in motor lateralization, observed in drug-naïve PD patients and (b) reduced inhibition - increased facilitation. Seeking to investigate the differential effect of dopamine depletion and subsequent substitution on compensatory mechanisms in non-drug-naïve PD, we studied 10 PD patients and 16 healthy controls, with patients undergoing two test sessions - "ON" and "OFF" medication. Using a simple visually-cued motor response task and fMRI, we investigated cortical motor activation - in terms of laterality, contra- and ipsilateral percent BOLD signal change and effective connectivity in the parametric empirical Bayes framework. We found that decreased motor lateralization persists in non-drug-naïve PD and is concurrent with decreased contralateral activation in the cortical motor network. Normal lateralization is not reinstated by dopamine substitution. In terms of effective connectivity, disease-related changes primarily affect ipsilaterally-lateralized homotopic cortical motor connections, while medication-related changes affect contralaterally-lateralized homotopic connections. Our findings suggest that, in non-drug-naïve PD, decreased lateralization is no longer an adaptive cortical mechanism, but rather the result of maladaptive changes, related to disease progression and long-term dopamine replacement. These findings highlight the need for the development of noninvasive therapies, which would promote the adaptive mechanisms of the PD brain.


Assuntos
Adaptação Fisiológica/fisiologia , Dopamina/fisiologia , Atividade Motora/fisiologia , Rede Nervosa/fisiopatologia , Doença de Parkinson/fisiopatologia , Adaptação Fisiológica/efeitos dos fármacos , Idoso , Teorema de Bayes , Estudos de Casos e Controles , Conectoma , Dominância Cerebral/fisiologia , Agonistas de Dopamina/farmacologia , Agonistas de Dopamina/uso terapêutico , Feminino , Pé/fisiopatologia , Mãos/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Doença de Parkinson/tratamento farmacológico , Avaliação de Sintomas
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