Bases Neurais da Aprendizagem

Students’ learning mechanisms and success are crucial to the advancement of education and knowledge. Therefore, understanding the neural basis of learning and applying it to educational programs can enhance how individuals acquire knowledge. Currently, educational programs are mostly centered on a teacher-based approach, which is not ideal for information retention. Instead, programs should be focused on achieving the three stages of learning: encoding, consolidation, and retrieval. In fact, current methods do not result in significant encoding (the first step). Strong encoding is associated with individual’s attention and focus on the material. Consolidation comes from the strengthening of neural pathways by providing meaning to the material being learned, and establishing strong connections to achieve long-term potentiation. Finally, retrieval is maximized when knowledge is fully established and a schema has been attained. It is important to take into account how education influences and can be used to optimize learning. Considering existing neural evidence, educational systems should change to a student-centered approach to improve learning.O sucesso e os mecanismos de aprendizado dos estudantes são cruciais para o avanço da educação e do conhecimento. Por este motivo a compreensão da base neural relacionada ao aprendizado, bem como a sua aplicação em programas de educação pode aprimorar o modo como os indivíduos adquirem conhecimento. No momento atual, os programas de educação são principalmente centrados em uma abordagem baseada no professor, a qual não é o método ideal para a retenção da informação. Ao invés, os programas deveriam estar focados em alcançar os três estágios de aprendizagem: codificação (“encoding”), consolidação (“consolidation”) e recuperação (“retrieval”). De fato, os métodos atuais não resultam sequer em uma significativa codificação (o primeiro estágio). Uma forte codificação está associada com a atenção e foco do indivíduo no material abordado. A consolidação vem do fortalecimento dos caminhos neurais, ao passo em que proporciona significado ao material que está sendo aprendido e estabelece fortes conexões para alcançar a potencialização de longo prazo. Finalmente, a recuperação é maximizada quando o conhecimento é totalmente estabelecido e um esquema alcançado. No geral, é importante levar em consideração como a educação afeta o aprendizado, e como esta pode ser utilizada para otimizá-lo. Levando em consideração a evidência neural existente, os sistemas de educação deveriam adotar uma abordagem centrada no aluno para melhorar a aprendizagem

Limits to clinical trials in surgical areas

Randomized clinical trials are considered to be the gold standard of evidence‐based medicine nowadays. However, it is important that we point out some limitations of randomized clinical trials relating to surgical interventions. There are limitations that affect the external and internal validity of many surgical study designs. Some limitations can be bypassed, but can make it more difficult for the study to be carried out. Other limitations cannot be bypassed. When it is intended to extrapolate the result of a randomized clinical trial, the premise is that the performed or to be performed intervention will be similar wherever applied and/or for every doctor using it. However, no matter how standardized the technique may be, the results are not similar for all surgeons, which implies a significant limitation to surgical randomized clinical trials concerning external validity. When considering the various limitations presented for performing surgical trials capable of generating scientific evidence within the patterns currently proposed in the evidence level classifications of medical publications, it is necessary to rethink whether those scientific evidence levels are similarly applicable to surgical works and to nonsurgical trials. We currently live in a time of supposed “inferiority” of surgical scientific works under the optics of the current quality criteria for a “suitable” clinical trial

Head-to-Head Comparison of Transcranial Random Noise Stimulation, Transcranial AC Stimulation, and Transcranial DC Stimulation for Tinnitus

Tinnitus is the perception of a sound in the absence of an external sound stimulus. This phantom sound has been related to plastic changes and hyperactivity in the auditory cortex. Different neuromodulation techniques such as transcranial magnetic stimulation and transcranial direct current stimulation (tDCS) have been used in an attempt to modify local and distant neuroplasticity as to reduce tinnitus symptoms. Recently, two techniques of pulsed electrical stimulation using weak electrical currents – transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS) – have also shown significant neuromodulatory effects. In the present study we conducted the first head-to-head comparison of three different transcranial electrical stimulation (tES) techniques, namely tDCS, tACS, and tRNS in 111 tinnitus patients by placing the electrodes overlying the auditory cortex bilaterally. The results demonstrated that tRNS induced the larger transient suppressive effect on the tinnitus loudness and the tinnitus related distress as compared to tDCS and tACS. Both tDCS and tACS induced small and non-significant effects on tinnitus symptoms, supporting the superior effects of tRNS as a method for tinnitus suppression

Pharmacological and Combined Interventions for the Acute Depressive Episode: Focus on Efficacy and Tolerability

Background: Use of antidepressants is the gold standard therapy for major depression. However, despite the large number of commercially available antidepressant drugs there are several differences among them in efficacy, tolerability, and cost-effectiveness. In addition the optimal augmentation strategy is still not clear when dealing with treatment-resistant depression, a condition that affects 15% to 40% of depressed patients. Methods: We therefore reviewed the main characteristics of these drugs regarding their efficacy, tolerability, side effects and cost-effectiveness, by accessing all meta-analyses and systematic reviews published from 2004 to 2009. In addition, we reviewed the augmentation strategy of associated antidepressants with neurostimulation therapies (such as transcranial magnetic stimulation [TMS] and transcranial direct current stimulation [tDCS]). A search was undertaken in MEDLINE, Web of Science, Cochrane, and Scielo databases. We included: 21 meta-analyses of antidepressant trials, 15 neurostimulation clinical trials and 8 studies of pharmacoeconomics. We then performed a comprehensive review on these articles. Results and Conclusion: Although recent meta-analyses suggest sertraline and escitalopram might have increased efficacy/tolerability, other studies and large pragmatic trials have not found these to be superior to other antidepressant drugs. Also, we did not identify any superior drug in terms of cost-effectiveness due to the different designs observed among pharmacoecomics studies. Side effects such as sexual dysfunction, gastrointestinal problems and weight gain were common causes of discontinuation. Tolerability was an important issue for novel neurostimulation interventions, such as TMS and tDCS. These therapies might be interesting augmentation strategies, considering their benign profile of side effects, if proper safety parameters are adopted

Learning circumference concepts from the didactical situations theory perspective

The circumference study, as its importance, it is one of the most relevant contents in the Analytical Geometry curriculum. However, the complexity of related concepts to this theme linked to the content fragmentation, it difficulties the students thinking of transforming geometrical problems into equations solution, systems or inequations. Within, in this article we present a partial report of a master research work, of qualitative mode, which aimed to develop and to evaluate an alternative methodology by using musical parody composition to the teaching of Mathematics in trying to contribute to the circumference concepts learning process. For that, we carried out a case study with 36 third year high school students of a public school from the city of Campina Grande, Paraíba. The research work was based and discussed on Brousseau Didactical Situation Theory. It was chosen triangulation technique for the data analyses, collected from interviews, questionnaires and a list of mathematical exercises. We concluded that the parody composition resource allowed the students better understand the concepts of center, ratio, cord and the definition of the general circumference equation, as they were capable to identify the relative positions which a circumference assumes in relation to an equation of a straight line and between two circumferences in the various concepts that differentiated them. Thus, we can state that the musical parody composition as a didactical resource can contribute to the learning of mathematical contents

Pharmacological and combined interventions for the acute depressive episode: focus on efficacy and tolerability

Andre R Brunoni1, Renerio Fraguas Jr1, Felipe Fregni21Department and Institute of Psychiatry, University of Sao Paulo, Brazil; 2Laboratory of Neuromodulation, Spaulding Rehabilitation Center, Harvard Medical School and Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USABackground: Use of antidepressants is the gold standard therapy for major depression. However, despite the large number of commercially available antidepressant drugs there are several differences among them in efficacy, tolerability, and cost-effectiveness. In addition the optimal augmentation strategy is still not clear when dealing with treatment-resistant depression, a condition that affects 15% to 40% of depressed patients.Methods: We therefore reviewed the main characteristics of these drugs regarding their efficacy, tolerability, side effects and cost-effectiveness, by accessing all meta-analyses and systematic reviews published from 2004 to 2009. In addition, we reviewed the augmentation strategy of associated antidepressants with neurostimulation therapies (such as transcranial magnetic stimulation [TMS] and transcranial direct current stimulation [tDCS]). A search was undertaken in MEDLINE, Web of Science, Cochrane, and Scielo databases. We included: 21 meta-analyses of antidepressant trials, 15 neurostimulation clinical trials and 8 studies of pharmacoeconomics. We then performed a comprehensive review on these articles.Results and Conclusion: Although recent meta-analyses suggest sertraline and escitalopram might have increased efficacy/tolerability, other studies and large pragmatic trials have not found these to be superior to other antidepressant drugs. Also, we did not identify any superior drug in terms of cost-effectiveness due to the different designs observed among pharmacoecomics studies. Side effects such as sexual dysfunction, gastrointestinal problems and weight gain were common causes of discontinuation. Tolerability was an important issue for novel neurostimulation interventions, such as TMS and tDCS. These therapies might be interesting augmentation strategies, considering their benign profile of side effects, if proper safety parameters are adopted.Keywords: acute depressive episode, pharmacological interventions, combined intervention

Simultaneous EEG Monitoring During Transcranial Direct Current Stimulation

Transcranial direct current stimulation (tDCS) is a technique that delivers weak electric currents through the scalp. This constant electric current induces shifts in neuronal membrane excitability, resulting in secondary changes in cortical activity. Although tDCS has most of its neuromodulatory effects on the underlying cortex, tDCS effects can also be observed in distant neural networks. Therefore, concomitant EEG monitoring of the effects of tDCS can provide valuable information on the mechanisms of tDCS. In addition, EEG findings can be an important surrogate marker for the effects of tDCS and thus can be used to optimize its parameters. This combined EEG-tDCS system can also be used for preventive treatment of neurological conditions characterized by abnormal peaks of cortical excitability, such as seizures. Such a system would be the basis of a non-invasive closed-loop device. In this article, we present a novel device that is capable of utilizing tDCS and EEG simultaneously. For that, we describe in a step-by-step fashion the main procedures of the application of this device using schematic figures, tables and video demonstrations. Additionally, we provide a literature review on clinical uses of tDCS and its cortical effects measured by EEG techniques

Clinical research in pediatric organ transplantation

Solid organ transplantation has greatly improved survival in children with end-stage disease, becoming one of the main treatment options in this population. Nonetheless, there are significant challenges associated with validating and optimizing the effects of these interventions in clinical trials. Therefore, we reviewed the main issues related to conducting clinical transplantation research in children. We divided these challenges into three different categories: (i) challenges related to surgical techniques and anesthetic procedures, (ii) challenges related to post-transplant care and (iii) challenges specific to a particular population group and disease type. Some of the observed burdens for clinical research in this field are related to the limitations of conducting studies with a placebo or sham procedure, determining the standard of care for a control group, low prevalence of cases, ethical concerns related to use of a placebo control group and lack of generalizability from animal studies and clinical trials conducted in adult populations. To overcome some of these barriers, it is necessary to utilize alternative clinical trial designs, such as observational studies or non-inferiority trials, and to develop multicenter collaborations to increase the recruitment rate. In conclusion, the lack of robust data related to pediatric transplantation remains problematic, and further clinical trials are needed to develop more efficacious and safer treatments

Using non-invasive brain stimulation to augment motor training-induced plasticity

Therapies for motor recovery after stroke or traumatic brain injury are still not satisfactory. To date the best approach seems to be the intensive physical therapy. However the results are limited and functional gains are often minimal. The goal of motor training is to minimize functional disability and optimize functional motor recovery. This is thought to be achieved by modulation of plastic changes in the brain. Therefore, adjunct interventions that can augment the response of the motor system to the behavioural training might be useful to enhance the therapy-induced recovery in neurological populations. In this context, noninvasive brain stimulation appears to be an interesting option as an add-on intervention to standard physical therapies. Two non-invasive methods of inducing electrical currents into the brain have proved to be promising for inducing long-lasting plastic changes in motor systems: transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). These techniques represent powerful methods for priming cortical excitability for a subsequent motor task, demand, or stimulation. Thus, their mutual use can optimize the plastic changes induced by motor practice, leading to more remarkable and outlasting clinical gains in rehabilitation. In this review we discuss how these techniques can enhance the effects of a behavioural intervention and the clinical evidence to date