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1.
Actual. psicol. (Impr.) ; 35(130)jun. 2021.
Artigo em Inglês | LILACS, SaludCR, PsiArg | ID: biblio-1383494

RESUMO

Abstract. Objective. This study characterized the electroencephalographic correlation (rEEG) between prefrontal and parietalcortices in young men while solving logical-mathematical problems after 18 sessions of cognitive training. Method. Two training groups were formed: one trained with gradually increased complexity (CT), the other with no increase in complexity (ST). Results. CT had a greater number of correct responses in the post-training evaluation than ST and showed a higher correlation between the left frontopolar-parietal cortices in almost all EEG bands, and between the dorsolateral-parietal cortices in the alpha1 band while solving math problems post-training. Results suggest that major functional synchronization between the left prefrontal and parietal cortices plays an important role in improving mathematical problem-solving after cognitive training.


Resumen Objetivo. El presente estudio caracteriza la correlación electroencefalográfica (rEEG) entre las cortezas prefrontal y parietal en hombres jóvenes durante la resolución de problemas lógico-matemáticos después de 18 sesiones de entrenamiento cognitivo. Método. Se formaron dos grupos de entrenamiento: uno entrenado con un incremento gradual de complejidad (CT) y el otro sin incremento de complejidad (ST). Resultados. El grupo CT presentó un mayor número de respuestas correctas que el grupo ST en la evaluación post entrenamiento, a su vez mostró un incremento en la correlación entre las cortezas frontopolar y parietal izquierdas en la mayoría de las bandas, así como entre las cortezas dorsolateral y parietal en la banda alfa1 durante la resolución de problemas posterior al entrenamiento. Los resultados sugieren que el incremento en la sincronización funcional entre las cortezas prefrontal y parietal izquierdas juega un rol importante en la resolución de problemas matemáticos después del entrenamiento cognitivo.


Assuntos
Humanos , Masculino , Adulto , Eletroencefalografia , Treino Cognitivo , Lógica , Matemática , México
2.
Neuroscience Bulletin ; (6): 826-840, 2019.
Artigo em Inglês | WPRIM | ID: wpr-776462

RESUMO

Motor timing is an important part of sensorimotor control. Previous studies have shown that beta oscillations embody the process of temporal perception in explicit timing tasks. In contrast, studies focusing on beta oscillations in implicit timing tasks are lacking. In this study, we set up an implicit motor timing task and found a modulation pattern of beta oscillations with temporal perception during movement preparation. We trained two macaques in a repetitive visually-guided reach-to-grasp task with different holding intervals. Spikes and local field potentials were recorded from microelectrode arrays in the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. We analyzed the association between beta oscillations and temporal interval in fixed-duration experiments (500 ms as the Short Group and 1500 ms as the Long Group) and random-duration experiments (500 ms to 1500 ms). The results showed that the peak beta frequencies in both experiments ranged from 15 Hz to 25 Hz. The beta power was higher during the hold period than the movement (reach and grasp) period. Further, in the fixed-duration experiments, the mean power as well as the maximum rate of change of beta power in the first 300 ms were higher in the Short Group than in the Long Group when aligned with the Center Hit event. In contrast, in the random-duration experiments, the corresponding values showed no statistical differences among groups. The peak latency of beta power was shorter in the Short Group than in the Long Group in the fixed-duration experiments, while no consistent modulation pattern was found in the random-duration experiments. These results indicate that beta oscillations can modulate with temporal interval in their power mode. The synchronization period of beta power could reflect the cognitive set maintaining working memory of the temporal structure and attention.

3.
Psychiatry Investigation ; : 16-26, 2019.
Artigo em Inglês | WPRIM | ID: wpr-741922

RESUMO

The core concept for pathophysiology in panic disorder (PD) is the fear network model (FNM). The alterations in FNM might be linked with disturbances in the autonomic nervous system (ANS), which is a common phenomenon in PD. The traditional FNM included the frontal and limbic regions, which were dysregulated in the feedback mechanism for cognitive control of frontal lobe over the primitive response of limbic system. The exaggerated responses of limbic system are also associated with dysregulation in the neurotransmitter system. The neuroimaging studies also corresponded to FNM concept. However, more extended areas of FNM have been discovered in recent imaging studies, such as sensory regions of occipital, parietal cortex and temporal cortex and insula. The insula might integrate the filtered sensory information via thalamus from the visuospatial and other sensory modalities related to occipital, parietal and temporal lobes. In this review article, the traditional and advanced FNM would be discussed. I would also focus on the current evidences of insula, temporal, parietal and occipital lobes in the pathophysiology. In addition, the white matter and functional connectome studies would be reviewed to support the concept of advanced FNM. An emerging dysregulation model of fronto-limbic-insula and temporooccipito-parietal areas might be revealed according to the combined results of recent neuroimaging studies. The future delineation of advanced FNM model can be beneficial from more extensive and advanced studies focusing on the additional sensory regions of occipital, parietal and temporal cortex to confirm the role of advanced FNM in the pathophysiology of PD.


Assuntos
Sistema Nervoso Autônomo , Conectoma , Lobo Frontal , Sistema Límbico , Neuroimagem , Neurotransmissores , Lobo Occipital , Transtorno de Pânico , Pânico , Lobo Parietal , Rabeprazol , Lobo Temporal , Tálamo , Substância Branca
4.
Clinical Psychopharmacology and Neuroscience ; : 125-129, 2019.
Artigo em Inglês | WPRIM | ID: wpr-739464

RESUMO

Transcranial direct current stimulation (tDCS) is a novel brain stimulation technique which has kindled hope in alleviating motor, language as well as cognitive deficits in neuronal injury. Current case report describes application of tDCS in two phases using two different protocols in a patient with hypoxic injury. In the first phase anodal stimulation of dorsolateral prefrontal cortex improved the language fluency. Subsequently, after 6 months second phase application of anodal stimulation over posterior parietal region targeted arithmetic and working memory deficits. Individualising the treatment protocols of brain stimulation, based on the lesion and the functional deficits, for neuro-rehabilitation is emphasised.


Assuntos
Humanos , Encéfalo , Protocolos Clínicos , Transtornos Cognitivos , Discalculia , Esperança , Hipóxia-Isquemia Encefálica , Memória de Curto Prazo , Neurônios , Lobo Parietal , Córtex Pré-Frontal , Reabilitação , Estimulação Transcraniana por Corrente Contínua
5.
Int. j. morphol ; 32(4): 1222-1227, Dec. 2014. ilus
Artigo em Inglês | LILACS | ID: lil-734662

RESUMO

This investigation was undertaken in order to quantify the effects of early polysensorial enrichment on the development of cortical pyramids, located in the parietal cortex of rats simultaneously submitted to protein-energy undernutrition. A short period of stimulation during suckling significantly decreases the cellular density in the cortical plate (phylogenetic-ontogenetic evolutionary index). Results suggest that the cerebral cortex develops according to a sophisticated neuronal network, which exhibits a notable degree of structural specificity, regulated by genetic and environmental clues. The most obvious prediction is that environmental influences are probably transduced as a structural expression in the developing parietal cortical plate.


La presente investigación se realizó con la finalidad de cuantificar los efectos del enriquecimiento polisensorial temprano sobre el desarrollo de células piramidales de la corteza parietal, en ratas que simultáneamente fueron sometidas a desnutrición calórico-proteica. Un breve periodo de estimulación durante el periodo de lactancia disminuyó significativamente la densidad celular en la placa cortical (índice evolutivo filogenético-ontogenético). Los resultados sugieren que la corteza cerebral se desarrolla de acuerdo con una red neuronal altamente sofisticada, la cual exhibe un notable grado de especificidad estructural regulada por claves genéticas y ambientales. La predicción más obvia es que las influencias ambientales son probablemente traducidas como expresión estructural en la placa cortical parietal.


Assuntos
Animais , Ratos , Lobo Parietal/anatomia & histologia , Lobo Parietal/crescimento & desenvolvimento , Desnutrição Proteico-Calórica , Meio Ambiente , Ratos Sprague-Dawley
6.
Chinese Journal of Physical Medicine and Rehabilitation ; (12): 687-690, 2013.
Artigo em Chinês | WPRIM | ID: wpr-442168

RESUMO

Objective To seek more direct evidence of the role of the posterior parietal cortex (PPC) in controlling visuospatial attention.Methods Forty healthy subjects took the Attention Network Test following continuous theta burst stimulation (cTBS) applied over the left or right PPC or sham stimulation.The Attention Network Test measures the alerting,orienting and executive control components of visual attention separately.Results Subjects responded to spatial cues significantly slower after cTBS.Alerting and orienting showed deficits after cTBS over the right PPC.cTBS over the left PPC resulted in significant improvements in alerting,but not in the orienting.Furthermore,there were significant differences in the alerting and orienting indices between cTBS over the left and right PPC,but not in the executive control index.Conclusions The results suggest that the right PPC is associated with spatial orienting and the alerting function.The findings supported the theory of inter-hemispheric competition for visuospatial attention.Visuospatial attention bias might be selectively modulated through cTBS.

7.
Journal of Korean Medical Science ; : 24-30, 2008.
Artigo em Inglês | WPRIM | ID: wpr-157450

RESUMO

To examine regional abnormalities in the brains of patients with obsessive-compulsive disorder (OCD), we assessed the gray matter (GM) density using voxel-based morphometry (VBM). We compared magnetic resonance images (MRIs) acquired from 71 OCD patients and 71 age- and gender-matched normal controls and examined the relationship between GM density and various clinical variables in OCD patients. We also investigated whether GM density differs among the subtypes of OCD compared to healthy controls. We detected significant reduction of GM in the inferior frontal gyrus, the medial frontal gyrus, the insula, the cingulate gyrus, and the superior temporal gyrus of OCD patients. A significant increase in GM density was observed in the postcentral gyrus, the thalamus, and the putamen. Some of these regions, including the insular and postcentral gyrus, were also associated with the severity of obsessive- compulsive symptoms. These findings indicate that the frontal-subcortical circuitry is dysfunctional in OCD, and suggest that the parietal cortex may play a role in the pathophysiology of this disease.


Assuntos
Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Encéfalo/patologia , Imageamento por Ressonância Magnética , Transtorno Obsessivo-Compulsivo/patologia , Lobo Parietal/patologia , Caracteres Sexuais
8.
Korean Journal of Anatomy ; : 315-324, 2005.
Artigo em Coreano | WPRIM | ID: wpr-647027

RESUMO

These experiments were performed to investigate the effect of saline, melatonin, stress, stressedmelatonin on TH immunoreactivity in rat brain. The animals were injected with melatonin (1 mg/kg, i.p.) after electric shocks for 15days. The results were as follows; 1. TH immunoreactive neurons in brain (the number of staining neuron & the stain intensity in LC and parietal cortex, the stain intensity in arcuate nucleus and median eminence of cerebral cortex) were significantly increased in stressed group compared with all the other groups. 2. TH immunoreactive neurons in brain (the number of staining neuron & the stain intensity in LC and parietal cortex, the stain intensity in arcuate nucleus and median eminence of cerebral cortex were significantly decreased in stressed-melatonin treated group compared with stressed group but were significantly increased compared with the other groups. These experiments indicate that its increase is inhibited by melatonin treatment even though, stress increases TH immunoreactivity in LC and Par.


Assuntos
Animais , Ratos , Núcleo Arqueado do Hipotálamo , Encéfalo , Córtex Cerebral , Eminência Mediana , Melatonina , Neurônios , Rabeprazol , Choque
9.
In. II International Congress on Neuroregeneration. Proceedings (selected papers). Rio de Janeiro, UFRJ, 2004. p.73-83, ilus.
Monografia em Inglês | LILACS | ID: lil-682596

RESUMO

Repetitive Magnetic Stimulation (rTMS) has shown to modify the excitability of targeted cortical regions in animals and humans, thus transiently altering the efficiency of neural projections within extended brain networks. Adequate processing and behavioral output depend on a given ‘state’ of functional interactions between cortical and subcortical nodes within this network. We applied rTMS trains targeted at the visuoparietal (VP) cortex, which is a crucial cortical node of an extended visuo-spatial neural network, in both, intact (n=2) and injured cats (n=2) with unilateral ablation of the VP region. All four intact cats were intensively trained in a set of visuo-spatial tasks consisting in the detection and localization of moving or static targets. In two of these cats, a 50 mm circular coil was centered on the left VP cortex and Sham or real rTMS was delivered during 20 minutes at 1 Hz. Real but not Sham rTMS significantly increased the number of errors in orienting responses towards static but not moving targets, presented at the contralateral visual hemifield (38±4%; and 48±3% p<0.05 vs. pre rTMS), whereas no increase respect to baseline was observed for ipsilateral targets (5±2%; 2±1%; n.s). Performance went back to baseline error levels 45 minutes after the end of the stimulation (4±2; 6±1%). In 2 other animals, the right or left parietal and primary visual cortex was surgically removed, generating a Daily stimulation with 1 Hz rTMS on the intact VP region resulted in a progressive reduction of detection¬orienting mistakes to moving but not static stimuli (down to 34±5% and 28±4% errors; p<0.05). We conclude that rTMS is able to interact with brain networks in both ways, transiently disrupting visuo-spatial processing in normal animals, and also canceling spatial neglect generated by lesions of the same areas. It constitutes, thus, a non-invasive ‘surgery-less’ method to manipulate brain activity and promote recovery after injuries.


Assuntos
Gatos , Córtex Cerebral , Neurologia , Estimulação Magnética Transcraniana
10.
Journal of Third Military Medical University ; (24)1984.
Artigo em Chinês | WPRIM | ID: wpr-549417

RESUMO

The projections of the hippocampus onto the cerebral cortex were studied in 31 rats after injections of horseradish peroxidase(HRP) into the parietal, frontal, and temporal lobes of the cerebral cortex respectively. The results were as follows:1) HRP labelled pyramidal cells were found in the CA1~CA3 of the dorsal and ventral hippocampus on both sides, more numerous on the ipsi-lateral side in all the cases. However, no HRP labelled cells could be identified in the CA4 or dentate gyrus in any case.2) Labelled neusons of hippocampo-temporal projection were more numerous than those of hippocampo-parietal or hippocampo-frontal projection. However, no difference could be revealed between those of hippocampo-parietal and hippocampo-frontal projections.The anatomical and functional significance of our findings were discussed

11.
Acta Anatomica Sinica ; (6)1954.
Artigo em Chinês | WPRIM | ID: wpr-577931

RESUMO

Objective To study the effects of hypoxia in uterus on nNOS expression in postnatal mouse parietal cortex and the learning and memory ability of adult mouse. Methods The number and shape of parietal cortex neurons during postnatal development with hypotonic hypoxia in uterus were observed by Nissl staining.The expression of nNOS in parietal cortex neurons during postnatal development with hypoxia in the uterus was studied with immunohistochmistry.The ability to learn and memorize in adult mouse was observed by Morris water maze. Results Compared with the control group,the number of neurons in parietal cortex from mouse during postnatal development in hypoxic group reduced significantly(P

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