927 resultados para Cerebral hemispheres


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hemispheric differences in the learning and generalization of pattern categories were explored in two experiments involving sixteen patients with unilateral posterior, cerebral lesions in the left (LH) or right (RH) hemisphere. In each experiment participants were first trained to criterion in a supervised learning paradigm to categorize a set of patterns that either consisted of simple geometric forms (Experiment 1) or unfamiliar grey-level images (Experiment 2). They were then tested for their ability to generalize acquired categorical knowledge to contrast-reversed versions of the learning patterns. The results showed that RH lesions impeded category learning of unfamiliar grey-level images more severely than LH lesions, whereas this relationship appeared reversed for categories defined by simple geometric forms. With regard to generalization to contrast reversal, categorization performance of LH and RH patients was unaffected in the case of simple geometric forms. However, generalization to of contrast-reversed grey-level images distinctly deteriorated for patients with LH lesions relative to those with RH lesions, with the latter (but not the former) being consistently unable to identify the pattern manipulation. These findings suggest a differential use of contrast information in the representation of pattern categories in the two hemispheres. Such specialization appears in line with previous distinctions between a predominantly lefthemispheric, abstract-analytical and a righthemispheric, specific-holistic representation of object categories, and their prediction of a mandatory representation of contrast polarity in the RH. Some implications for the well-established dissociation of visual disorders for the recognition of faces and letters are discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A critical review of the auditory selective attention literature is presented, particular reference is made to methodological issues arising from the asymmetrical hemispheric representation of language in the context of the dominant research technique dichotic shadowing. Subsequently the concept of cerebral localization is introduced, and the experimental literature with reference to models of laterality effects in speech and audition discussed. The review indicated the importance of hemispheric asymmetries insofar as they might influence the results of dichotic shadowing tasks. It is suggested that there is a potential overlap between models of selective attention and hemispheric differences. In Experiment I, ~ a key experiment in auditory selective attention is replicated and by exercising control over possible laterality effects some of the conflicting results of earlier studies were reconciled. The three subsequent experiments, II, III and IV, are concerned with the recall of verbally shadowed inputs. A highly significant and consistent effect of ear of arrival upon the serial position of items recalled is reported. Experiment V is directed towards an analysis of the effect that the processing of unattended inputs has upon the serial position of attended items that are recalled. A significant effect of the type of unattended material upon the recall of attended items was found to be influenced by the ear of arrival of inputs. In Experiment VI, differences between the two ears as attended and unattended input channels were clarified. Two main conclusions were drawn from this work. First, that the dichotic shadowing technique cannot control attention. Instead the task aprocessing both channels of dichotic inputs is unevenly shared bet\'reen the hemispheres as a function of the ear shadowed. Consequently, evidence for the processing of unattended information is considered in terms of constraints imposed by asymmetries in the functional organization of language, not in terms of a limited processing capacity model. The second conclusion to be drawn is that laterality differences can be effectively examined using the dichotic shadowing technique, a new model of laterality differences is proposed and discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT

Relevância:

20.00% 20.00%

Publicador:

Resumo:

1 Dilatation of the cerebral vasculature is recognised to be involved in the pathophysiology of migraine. Furthermore, elevated levels of prostaglandin E2 (PGE2) occur in the blood, plasma and saliva of migraineurs during an attack, suggestive of a contributory role. In the present study, we have characterised the prostanoid receptors involved in the relaxation and contraction of human middle cerebral arteries in vitro. 2 In the presence of indomethacin (3μM) and the TP receptor antagonist GR32191 (1 μM), PGE2 was found to relax phenylephrine precontracted cerebral arterial rings in a concentration-dependent manner (mean pEC50 8.0 ± 0.1, n = 5). 3 Establishment of a rank order of potency using the EP4 > EP2 agonist 11-deoxy PGE1, and the EP2 > EP4 agonist PGE1-OH (mean pEC 50 of 7.6 ± 0.1 (n = 6) and 6.4 ± 0.1 (n = 4), respectively), suggested the presence of functional EP4 receptors. Furthermore, the selective EP2 receptor agonist butaprost at concentrations < 1 μM failed to relax the tissues. 4 Blockade of EP 4 receptors with the EP4 receptor antagonists AH23848 and EP4A caused significant rightward displacements in PGE2 concentration-response curves, exhibiting pA2 and pKB values of 5.7 ± 0.1, n = 3, and 8.4, n = 3, respectively. 5 The IP receptor agonists iloprost and cicaprost relaxed phenylephrine precontracted cerebral arterial rings (mean pEC50 values 8.3 ± 0.1 (n = 4) and 8.1 ± 0.1 (n = 9), respectively). In contrast, the DP and FP receptor agonists PGD2 and PGFα2 failed to cause appreciable relaxation or contraction at concentrations of up to 30 μM. In the absence of phenylephrine contraction and GR32191, the TP receptor agonist U46619 caused concentration-dependent contraction of cerebral artery (mean pEC50 7.4 ± 0.3, n = 3). 6 These data demonstrate the presence of prostanoid EP4 receptors mediating PGE2 vasodilatation of human middle cerebral artery. IP receptors mediating relaxation and TP receptors mediating contraction were also functionally demonstrated.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

An estimated 30% of individuals with autism spectrum disorders (ASD) remain minimally verbal into late childhood, but research on cognition and brain function in ASD focuses almost exclusively on those with good or only moderately impaired language. Here we present a case study investigating auditory processing of GM, a nonverbal child with ASD and cerebral palsy. At the age of 8 years, GM was tested using magnetoencephalography (MEG) whilst passively listening to speech sounds and complex tones. Where typically developing children and verbal autistic children all demonstrated similar brain responses to speech and nonspeech sounds, GM produced much stronger responses to nonspeech than speech, particularly in the 65–165 ms (M50/M100) time window post-stimulus onset. GM was retested aged 10 years using electroencephalography (EEG) whilst passively listening to pure tone stimuli. Consistent with her MEG response to complex tones, GM showed an unusually early and strong response to pure tones in her EEG responses. The consistency of the MEG and EEG data in this single case study demonstrate both the potential and the feasibility of these methods in the study of minimally verbal children with ASD. Further research is required to determine whether GM's atypical auditory responses are characteristic of other minimally verbal children with ASD or of other individuals with cerebral palsy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Stroke is nowadays one of the main causes of death in Brazil and worldwide. During the rehabilitation process, patients undergo physioterapic exercises based on repetition, which may cause them to feel little progress is being made. Focusing on themes from the areas of Human-Computer Interaction and Motor Imagery, the present work describes the development of a digital game concept aimed at motor rehabilitation to the neural rehabilitation of patients who have suffered a stroke in a playful and engaging way. The research hypothesizes that an interactive digital game based on Motor Imagery contributes to patients' raised commitment in the stroke sequel rehabilitation process. The research process entailed the investigation of 10 subjects who live with sequels caused by stroke - it was further established that subjects were over 60 years old. Using as foundation an initial survey regarding target-users' specificities, where an investigation on subjectrelated aspects was carried out through Focus Group (n=9) and Contextual Analysis (n=3), having as subjects elderly individuals, a list with the necessary requirements for the conceptualization of a digital game was fleshed out. The initial survey also enabled the establishment of preliminary interactions for the formulation of game prototypes. At first, low-resolution prototypes were used, with two distinct interaction models for the game - one with a direct approach to the Motor Imagery concept, and another using a narrative with characters and scene settings. The goal was to verify participants' receptivity regarding the addition of playful activities into game dynamics. Prototypes were analyzed while being used by five patients, through the Cooperative Evaluation technique. The tests indicated a preference for option with elements in a playful narrative. Based on these results high fidelity prototypes were created, where concepts close to the game's final version were elaborated. The High Fidelity prototype was also evaluated with four patients through the Cooperative Evaluation technique. It was concluded that elderly individuals and patients were receptive to the idea of a digital game for the rehabilitation from sequels caused by stroke; that, for the success of devices aimed at these cohorts, their contexts, needs and expectations must be respected above all; and that user-centered design is an essential approach in that regard.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present study aimed to understand the experience of being a family caregiver of a patient with Cerebrovascular Accident (CVA). The relevance of the study is to prove existence of a large number of caregivers of incapacitated patients, due to the CVA and it is not an academic research object, according to the literature. It is a qualitative research, which the guiding principle is the oral history of life, according to the theoretical foundation and operating of Meihy. Therefore, the following steps were highlighted: the target community, composed of all family caregivers of CVA patients; the colony, composed by family caregivers of CVA patients assisted by Home Care Service (HCS) of the Hospital José Pedro Bezerra (HJPB), in the city of Natal/RN; the network was composed of six caregivers who met the criteria for inclusion, and as zero point the first volunteer group. The population was composed of all family caregivers of patients attended by the HCS, of the HJPB having been addressed through interviews. For the empirical research there was the consent of that institution and approval by the Ethics Committee in Research of the Federal University of Rio Grande do Norte as CAAE 24569413.0.0000.5537 and, above all, with the acquiescence of employees in participating in the investigation, signing an informed consent. Of the empirical material, five categories of analysis were identified: the sense of being a caregiver; what has changed in the life of the caregiver; the feelings emerge in the relationship of care; the distance from family and friends; difficulties faced by the caregiver. The results show that the caregiver's life goes through profound transformations within the family as well as in all spheres of life. For the caregivers, assuming the care of a relative with CVA means renunciation and donation, compromising sometimes the individual projects and the family as a whole. In addition, they point out the confrontation of difficulties within the the assistance and humanization in healthcare, information, physical and emotional overload, as well as financial problems. Despite all the adversities that compromise the caregiver's life, it was possible to identify attitudes of resilience among caregivers, making them their daily life less strenuous and with more lightness. It is expected, therefore, that this research can contribute to a better orientation of professionals with the caregivers

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

Relevância:

20.00% 20.00%

Publicador:

Resumo:

La inclusión de los niños con discapacidad en la educación infantil, además de ser un tema poco planteado en la comunidad científica, es un reto actual en lo que se refiere a la práctica docente. Basándose en este aspecto, nuestro objetivo en esta investigación realizada, que resultó en la elaboración de este trabajo, fue analizar cómo se procesa la práctica docente con vistas a la inclusión escolar de un niño con parálisis cerebral, en un Centro Municipal de Educación Infantil (CMEI), en la ciudad de Natal / RN. Más específicamente, buscamos: reflexionar sobre la práctica de la profesora responsable por la clase, en lo que se refiere al desarrollo del niño con parálisis cerebral; analizar las interacciones entre educador y niño con parálisis cerebral; observar la práctica docente en la perspectiva de favorecer la interacción entre el niño con parálisis cerebral y otros niños. Para ello, realizamos una pesquisa exploratoria, cualitativa, y así que optamos por el método del Estudio de Caso. Utilizamos como procedimientos metodológicos el análisis documental, la investigación bibliográfica, la entrevista semiestructurada, la observación y la filmación de escenas relacionadas a la práctica docente. Los sujetos de la investigación fueron la profesora y el niño con parálisis cerebral. Los datos construidos durante la investigación señalaron el hecho de que la práctica de la profesora no estaba encaminada a las necesidades específicas de la alumna con parálisis cerebral, todavía, se desarrollaba de una manera similar para todos los niños en la clase. La presencia de limitaciones significativas para la inclusión de la niña con parálisis cerebral en la educación infantil puede ser considerado como el resultado de la ausencia de una adecuada preparación docente, tanto en el nivel de la formación inicial, cuanto de una formación continua y también la escasez de directrices para el maestro, en proceso; directrices estas acerca de la educación de los niños con parálisis cerebral, lo que hacía imposible a la profesora contribuir de manera efectiva a su mayor desarrollo cognitivo y social.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: Slow abdominal breathing (SAB) stimulates baroreflex and generates respiratory sinus arrhythmia, changing cardiovascular, emotional and cerebral systems acute and chronically. However, although meditative practices have been receiving increasingly attention in the last years, there is no agreement on the neurophysiological changes underlying them, mainly because of the lack of topographical pieces of information. Purpose: We aimed to analyze the acute effect of SAB on brain activity, emotional and cardiovascular responses in untrained subjects in meditative techniques. Methods: Seventeen healthy adults’ men were assessed into two different sessions in a random and crossed order. Into experimental session, they breathed in 6 cycles/minute and in control session they kept breathing in normal rate, both for 20 minutes. xi Before, during, and after each session we assessed brain activity using electroencephalography (EEG), anxiety, mood, heart rate variability (HRV) and blood pressure. The sLORETA software was used to analyze EEG data for source localization of brain areas in which activity was changed. Results: The sLORETA showed that beta band frequency was reduced in frontal gyrus (P<0.01) and anterior cingulate cortex (P<0.05) both during and after SAB (P<0.05) compared to the moment before it. There was no change in brain activity in control session. Additionally, a two-way repeated measures ANOVA showed that there was no effect on anxiety (P>0.8) and mood (P>0.08). There were improvements in HRV (P<0.03), with increased RR interval and decreased HR after SAB, as well as increased SDNN, RMSSD, pNN50, low frequency, LF/HF ratio, and total power during it, with no changes in SBP and DBP. Conclusions: We conclude that SAB is able to change brain activity in areas responsible for emotional processing, even without behavioral changes. Furthermore, SAB improves HRV and does not change blood pressure in normotensive.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Stroke is the leading cause of long-term disability among adults and motor relearning is essential in motor sequelae recovery. Therefore, various techniques have been proposed to achieve this end, among them Virtual Reality. The aim of the study was to evaluate electroencephalographic activity of stroke patients in motor learning of a virtual reality-based game. The study included 10 patients with chronic stroke, right-hande; 5 with left brain injury (LP), mean age 48.8 years (± 4.76) and 5 with injury to the right (RP), mean age 52 years (± 10.93). Participants were evaluated for electroencephalographic (EEG) activity and performance while performing 15 repetitions of darts game in XBOX Kinect and also through the NIHSS, MMSE, Fugl-Meyer and the modified Ashworth scale. Patients underwent a trainning with 45 repetitions of virtual darts game, 12 sessions in four weeks. After training, patients underwent reassessment of EEG activity and performance in virtual game of darts (retention). Data were analyzed using ANOVA for repeated measures. According to the results, there were differences between the groups (PD and PE) in frequencies Low Alpha (p = 0.0001), High Alpha (p = 0.0001) and Beta (p = 0.0001). There was an increase in alpha activation powers and a decrease in beta in the phase retention of RP group. In LP group was observed increased alpha activation potency, but without decrease in beta activation. Considering the asymmetry score, RP group increased brain activation in the left hemisphere with the practice in the frontal areas, however, LP group had increased activation of the right hemisphere in fronto-central areas, temporal and parietal. As for performance, it was observed a decrease in absolute error in the game for RP group between assessment and retention (p = 0.015), but this difference was not observed for LP group (p = 0.135). It follows then that the right brain injury patients benefited more from darts game training in the virtual environment with respect to the motor learning process, reducing neural effort in ipsilesionais areas and errors with the practice of the task. In contrast, patients with lesions in left hemisphere decrease neural effort in contralesionais areas important for motor learning and showed no performance improvements with practice of 12 sessions of virtual dart game. Thus, the RV can be used in rehabilitation of stroke patients upper limb, but the laterality of the injury should be considered in programming the motor learning protocol.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Cerebral palsy is a severe condition usually caused by decreased brain oxygenation during pregnancy, at birth or soon after birth. Conventional treatments for cerebral palsy are often tiresome and expensive, leading patients to quit treatment. In this paper, we describe a virtual environment for patients to engage in a playful therapeutic game for neuropsychomotor rehabilitation, based on the experience of the occupational therapy program of the Nucleus for Integrated Medical Assistance (NAMI) at the University of Fortaleza, Brazil. Integration between patient and virtual environment occurs through the hand motion sensor “Leap Motion,” plus the electroencephalographic sensor “MindWave,” responsible for measuring attention levels during task execution. To evaluate the virtual environment, eight clinical experts on cerebral palsy were subjected to a questionnaire regarding the potential of the experimental virtual environment to promote cognitive and motor rehabilitation, as well as the potential of the treatment to enhance risks and/or negatively influence the patient’s development. Based on the very positive appraisal of the experts, we propose that the experimental virtual environment is a promising alternative tool for the rehabilitation of children with cerebral palsy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: stroke causes long-term impairments, limitation of activities and restriction in participation in daily life situations, especially for upper limb impairment (UL). Action Observation (AO) has been used for the rehabilitation of UL in these patients. It's a multisensory therapy which consists in observing a healthy subject performing a motor task, followed by physical practice. Objectives: assess whether the AO improves motor function of UL and dependence for activities of daily living (ADLs) of stroke patients or cause any adverse effects. Search methods: a search strategy was words and terms used for the identification of articles, in the following scientific basis Cochrane Central Register of Controlled Trials; MEDLINE; PsycINFO; CINAHL and LILACS. In addition to manual search of the references of articles and search for theses and dissertations in Portal Capes and LILACS. The identification of the studies was conducted from October to December 2015, being the last search on December 3. Selection criteria: randomised controlled trials (RCT) involving adults with stroke who had deficits in upper limb function and used AO as an intervention. Data collection and analysis: the data extracted from the studies were used to analyze the risk of bias, the effect of the treatment and the quality of the body of evidence. Main results: 6 studies were included, totaling 270 patients. The primary outcome analyzed was the motor function of MS. Were combined in meta-analyzes studies comparing AO versus placebo or an active control, considering the immediate and long-term effect (n=241). Regarding the motor function of the arm (5 trials), the estimated effect for the therapy was not significant. However, when considering the hand function estimating the effect was favorable to the group that conducted the AO, in short (mean difference = 6.93, 95% CI 1.48 to 12.39; P = 0.01) and long-term (mean difference = 7.57; 95% CI 1.34 the 13.80; p = 0.02). Unable to perform the analysis for functional dependency. The studies showed a low or uncertain risk of bias, but the quality of evidence the body was considered low and very low quality. Authors’ conclusions: AO was effective in improving hand function of stroke patients. Despite the low quality evidence that the use of OA in clinical practice should not be discouraged. RCT new studies should be conducted with greater methodological rigor and larger samples, covering important outcomes such as functional dependence for ADLs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: Gait after stroke is characterized by a significant asymmetry between the lower limbs, with predominant use of the non-paretic lower limb (NPLL) over using the paretic lower limb. Accordingly, it has been suggested that adding load/weight to the NPLL as a form of restricting the movement of this limb may favor the use of the paretic limb, reducing interlimb asymmetry. However, few studies have been conducted up to this moment, which only investigated the immediate effects of this practice. Objectives: 1) Investigating whether there is an influence of adding load to the NPLL during treadmill training on cardiovascular parameters and on gait performance of individuals with stroke, compared to treadmill training without load addition; 2) Analyzing the effects of treadmill training with and without load added to the NPLL on kinematic parameters of each lower limb during gait; 3) Analyzing the effects of treadmill training with and without load added to the NPLL on measurements of functional mobility and postural balance of these patients. Materials and Methods: This is a randomized single blinded clinical trial involving 38 subjects, with a mean age of 56.5 years, at the subacute post-stroke phase (with mean time since stroke of 4.5 months). Participants were randomly assigned into an experimental group (EG) or control group (CG). EG (n= 19) was submitted to gait training on a treadmill with the addition of load to the NPLL by ankle weights equivalent to 5% of body weight. CG (n= 19) was only submitted to gait training on a treadmill. Behavioral strategies which included home exercises were also applied to both groups. The interventions occurred daily for two consecutive weeks (Day 1 to Day 9), being of 30 minutes duration each. Outcome measures: postural balance (Berg Functional Balance Scale – BBS), functional mobility (Timed Up and Go – TUG; kinematic variables of 180° turning) and kinematic gait variables were assessed at baseline (Day 0), after four training sessions (Day 4), after nine training sessions (Day 9), and 40 days after completion of training (Follow-up). Cardiovascular parameters (mean arterial pressure and heart rate) were evaluated at four moments within each training session. Analysis of variance (ANOVA) was used to compare outcomes between EG and CG in the course of the study (Day 0, Day 4, Day 9 and Follow-up). Unpaired t-tests allowed for intergroup comparison at each training session. 5% significance was used for all tests. Results: 1) Cardiovascular parameters (systemic arterial pressure, heart rate and derivated variables) did not change after the interventions and there were no differences between groups within each training session. There was an improvement in gait performance, with increased speed and distance covered, with no statistically significant difference between groups. 2) After the interventions, patients had increased paretic and non-paretic step lengths, in addition to exhibiting greater hip and knee joint excursion on both lower limbs. The gains were observed in the EG and CG, with no statistical difference between the groups and (mostly) maintained at follow-up. 3) After the interventions, patients showed better postural balance (higher scores on BBS) and functional mobility (reduced time spent on the TUG test and better performance on the 180° turning). All gains were observed in the EG and CG, with no statistically significant difference between groups and were maintained at follow-up. Conclusions: The addition of load to the NPLL did not affect cardiovascular parameters in patients with subacute stroke, similar to treadmill training without load, thus seemingly a safe training to be applied to these patients. However, the use of the load did not bring any additional benefits to gait training. The gait training program (nine training sessions on a treadmill + strategies and exercises for paretic limb stimulation) was useful for improving gait performance and kinematics, functional mobility and postural balance, and its use is suggested to promote the optimization of these outcomes in the subacute phase after stroke.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Este trabajo tiene como meta el desarrollo de un sistema de neurorrehabilitación mediante realidad virtual para pacientes con problemas motores en las extremidades superiores provocados por un daño cerebral. Para entender y enfrentarse de manera correcta al problema, se han revisado todos los aspectos concernientes al daño cerebral y déficits motores derivados así como las terapias empleadas para su rehabilitación, como las que utilizan tecnologías asistidas como la realidad virtual. Se han expuesto las ventajas que han llevado a utilizar esta terapia en el proyecto y se han mencionado algunos estudios de investigación previos y con resultados favorables. Por último, se ha hecho hincapié en las novedades (embodiment y neuronas espejo) que aporta este proyecto con las que se podría acelerar la rehabilitación de los pacientes incidiendo en la plasticidad cerebral. En lo que se refiere al desarrollo del entorno, se ha utilizado el motor de videojuegos Unity 3D, con el que se ha integrado el dispositivo Myo Armband, para capturar el movimiento, y las gafas de realidad virtual Oculus Rift DK2. Durante la terapia, el paciente tiene que superar una serie de niveles definidos por el terapeuta y, para ello, debe realizar un alcance y tocar un botón un número de veces por cada nivel. En cada nivel, el esfuerzo que tiene que realizar el paciente es distinto, dependiendo de la distancia a la que se encuentre el botón (relativa al calibrado previo del paciente) e igualmente, está definido por el terapeuta. También se lleva a cabo un registro de las aceleraciones y del porcentaje de acierto del paciente en un fichero, para llevar un control de su progreso. Como conclusión, cabe mencionar que el entorno desarrollado es adaptable a las posibilidades de cada paciente, permitiendo una recuperación óptima. Se trata de un sistema de bajo coste, intuitivo y que lleva a cabo un registro de datos de la actividad del paciente, lo que posibilita, como trabajo futuro, el control de forma remota por parte del terapeuta. Todos estos aspectos dejan abierta la posibilidad de que el paciente lo utilice a domicilio, con las ventajas que conlleva. Del mismo modo, el sistema se podría adaptar fácilmente para la rehabilitación de las extremidades inferiores. Tras su análisis, los investigadores expertos en la materia del Consejo Superior de Investigaciones Científicas afirman que el sistema satisface con creces su propósito. Con todo esto, se concluye que este entorno tiene un excelente presente y un futuro muy prometedor.