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BACKGROUND: Current available therapies for Parkinson disease (PD) have strong limitations, and patients usually present with refractory symptoms despite all efforts. Deep brain stimulation (DBS), which has been used in PD patients for decades (since 1987), has best indications for symptoms like tremor, motor fluctuations, or dyskinesia. However, postural instability and gait disturbances (PIGD) have restricted benefits with DBS. In 2009, spinal cord stimulation (SCS), a well-established therapy for chronic pain, has emerged as a potential alternative therapy that may help control unresponsive symptoms such as bradykinesia, PIGD, and freezing of gait. METHODS: The main studies regarding SCS in PD are reviewed here from the first studies in animal models to the latest clinical trials. CONCLUSIONS: Despite promising findings, the heterogeneity of methodologies used and small samples in human studies pose a challenging problem to be addressed in order to have robust clinical evidence to support SCS as a viable PD treatment.

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Marmosets (Callithrix jacchus) are small non-human primates that are gaining popularity in biomedical and preclinical research, including the neurosciences. Phylogenetically, these animals are much closer to humans than rodents. They also display complex behaviors, including a wide range of vocalizations and social interactions. Here, an effective stereotaxic neurosurgical procedure for implantation of recording electrode arrays in the common marmoset is described. This protocol also details the pre- and postoperative steps of animal care that are required to successfully perform such a surgery. Finally, this protocol shows an example of local field potential and spike activity recordings in a freely behaving marmoset 1 week after the surgical procedure. Overall, this method provides an opportunity to study the brain function in awake and freely behaving marmosets. The same protocol can be readily used by researchers working with other small primates. In addition, it can be easily modified to allow other studies requiring implants, such as stimulating electrodes, microinjections, implantation of optrodes or guide cannulas, or ablation of discrete tissue regions.

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Operant-conditioning boxes are widely used in animal training, allowing researchers to shape specific behaviors through reinforcements and/or punishments. Commercially available devices are expensive and run with proprietary software and hardware, hampering adaptations for the specific needs of an experiment. Therefore, many low-cost and open-source devices have recently been developed, but there are still few options for studying auditory behaviors. To overcome this problem, we developed a device based on a computer and an Arduino Mega 2560 board, named OBAT (Operant Box for Auditory Tasks), designed to present two different auditory stimuli to small primates. It has three modules: sound delivery, response bars, and reward system. We estimate that OBAT is at least 4-10 times cheaper than commercially available operant-conditioning boxes. Data from a behavioral pilot test ensured that the device can be used to train a marmoset in an auditory discrimination task. In addition, despite its low cost, accuracy tests showed that the OBAT operates with a high temporal precision. All schematics and software source code are available so that other groups can easily replicate the experiment or adapt the device to their own needs.

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The orienting attention network is responsible for prioritizing sensory input through overt or covert shifts of attention among targets. The ability to disengage attention is essential for the proper functioning of this network. In addition to its importance for proper orienting, deficits in disengagement have been recently implicated in autism disorders. Despite its importance, the neural mechanisms underlying disengagement processing are still poorly understood. In this study, the involvement of the superior colliculus (SC) in disengagement was investigated in unrestrained rats that had been trained in a two-alternative light-guided spatial choice task. At each trial, the rats had to choose one of two paths, leading either to a large or a small reward, based on 1 (single-cue) or 2 (double-cue) lights. The task consisted of serial trials with single- and/or double-cue lights, and rats could acquire a large reward if the rats chose infrequent lights when infrequent cue lights were presented after preceding frequent cue lights. Experiment 1 included trials with either single- or double-cue lights, and infrequent trials with double-cue lights required both attentional disengagement and shift of attention from preceding frequent single-cue lights, while experiment 2 included only trials with single-cue lights requiring shifts of attention but not attentional disengagement. The results indicated that temporary inactivation of the SC by muscimol injections selectively impaired performance on trials requiring disengagement. No impairment was observed on the other trials, in which attention disengagement was not required. The results provide the first evidence that the SC is necessary for attentional disengagement.

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Recently, the curriculum and the educational methodologies associated with health sciences courses are being reviewed and adapted. Pre-clinical sciences, such as anatomy and embryology are as well subjected to those changes. In human embryology courses it is common to use models to represent the different phases of development to facilitate learning, since the students can see and touch the models, obtaining knowledge by analogies. The purpose of the present study was to investigate if the construction of models by the students during practical embryology classes would improve or facilitate their learning. One year after the classes, 60 students answered a questionnaire with nine objective questions, including spaces for suggestions and observations. The student's responses suggested that the construction of models contributed to their learning.

Recientemente, el plan de estudios y las metodologías educativas asociadas a los cursos de ciencias de la salud están siendo revisados y adaptados. Ciencias pre-clínicas tales como la Anatomía y la Embriología son también sometidas a cambios. En los cursos de Embriología Humana, es común el uso de modelos para representar las diferentes fases del desarrollo, y así facilitar el aprendizaje, ya que los estudiantes pueden ver y tocar los modelos, así se realiza la obtención de conocimientos por medio de analogías. El propósito del presente estudio fue investigar si la construcción de modelos por parte de los estudiantes, durante las clases prácticas de Embriología, mejora o facilita su aprendizaje. Después de un año, 60 estudiantes respondieron a un cuestionario con nueve preguntas objetivas, incluidos los espacios para sugerencias y observaciones. De acuerdo con las respuestas de los estudiantes, la construcción de modelos han contribuido a su aprendizaje.

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This strict localizationism had and still has its importance for the development of Neurosciences, since the analysis of changes in mental processes resulting from brain damage became the basis for understanding the brain organization. The human parietal cortex is a highly differentiated structure, consisting of citoarchitectonically defined subareas that are connected to other cortical and subcortical areas. Patients with lesions in the parietal cortex develop various types of neuropsychological manifestations, depending on the specific location of the lesion and the corresponding hemisphere and these lesions in this lobe do not cause modal specific disturbances. The establishment of homologies between the parietal region in humans and primates can be of great contribution in trying to unravel the various functions and complexity of this area.

O localizacionismo estrito teve e ainda tem a sua importância para o desenvolvimento da Neurociência, uma vez que a análise de mudanças nos processos mentais resultantes de danos cerebrais se tornou a base para a compreensão da organização cerebral. O córtex parietal humano é uma estrutura altamente diferenciada, composta por subáreas histologicamente definidas que estão ligadas a outras áreas corticais e subcorticais. Pacientes com lesões no córtex parietal desenvolvem vários tipos de manifestações neuropsicológicas, dependendo do local específico da lesão e do hemisfério correspondente, mas estas lesões não causam perturbações modais específicas. O estabelecimento de homologias entre a região parietal em seres humanos e os primatas podem ser de grande contribuição na tentativa de desvendar as diversas funções e complexidade desta área.

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This strict localizationism had and still has its importance for the development of Neurosciences, since the analysis of changes in mental processes resulting from brain damage became the basis for understanding the brain organization. The human parietal cortex is a highly differentiated structure, consisting of citoarchitectonically defined subareas that are connected to other cortical and subcortical areas. Patients with lesions in the parietal cortex develop various types of neuropsychological manifestations, depending on the specific location of the lesion and the corresponding hemisphere and these lesions in this lobe do not cause modal specific disturbances. The establishment of homologies between the parietal region in humans and primates can be of great contribution in trying to unravel the various functions and complexity of this area.

O localizacionismo estrito teve e ainda tem a sua importância para o desenvolvimento da Neurociência, uma vez que a análise de mudanças nos processos mentais resultantes de danos cerebrais se tornou a base para a compreensão da organização cerebral. O córtex parietal humano é uma estrutura altamente diferenciada, composta por subáreas histologicamente definidas que estão ligadas a outras áreas corticais e subcorticais. Pacientes com lesões no córtex parietal desenvolvem vários tipos de manifestações neuropsicológicas, dependendo do local específico da lesão e do hemisfério correspondente, mas estas lesões não causam perturbações modais específicas. O estabelecimento de homologias entre a região parietal em seres humanos e os primatas podem ser de grande contribuição na tentativa de desvendar as diversas funções e complexidade desta área.