Alessandro Pereira da Silva

Virtual environment to quantify the influence of colour stimuli on the performance of tasks requiring attention

BackgroundRecent studies indicate that the blue-yellow colour discrimination is impaired in ADHD individuals. However, the relationship between colour and performance has not been investigated. This paper describes the development and the testing of a virtual environment that is capable to quantify the influence of red-green versus blue-yellow colour stimuli on the performance of people in a fun and interactive way, being appropriate for the target audience.MethodsAn interactive computer game based on virtual reality was developed to evaluate the performance of the players.The games storyline was based on the story of an old pirate who runs across islands and dangerous seas in search of a lost treasure. Within the game, the player must find and interpret the hints scattered in different scenarios. Two versions of this game were implemented. In the first, hints and information boards were painted using red and green colours. In the second version, these objects were painted using blue and yellow colours. For modelling, texturing, and animating virtual characters and objects the three-dimensional computer graphics tool Blender 3D was used. The textures were created with the GIMP editor to provide visual effects increasing the realism and immersion of the players. The games were tested on 20 non-ADHD volunteers who were divided into two subgroups (A1 and A2) and 20 volunteers with ADHD who were divided into subgroups B1 and B2. Subgroups A1 and B1 used the first version of the game with the hints painted in green-red colors, and subgroups A2 and B2 the second version using the same hints now painted in blue-yellow. The time spent to complete each task of the game was measured.ResultsData analyzed with ANOVA two-way and posthoc TUKEY LSD showed that the use of blue/yellow instead of green/red colors decreased the game performance of all participants. However, a greater decrease in performance could be observed with ADHD participants where tasks, that require attention, were most affected.ConclusionsThe game proved to be a user-friendly tool capable to detect and quantify the influence of color on the performance of people executing tasks that require attention and showed to be attractive for people with ADHD.

Meniscal tears: comparison of the conventional spin-echo and fast spin-echo techniques through image processing.

BackgroundConventional spin-echo (PD-CSE) and fast spin-echo (PD-FSE) techniques are frequently used to detect meniscal tears. However, the time delay for imaging with PD-CSE has resulted in its replacement with faster techniques, such as proton density fast spin-echo (PD-FSE), which has become a frequent tool at most diagnostic centres.Qualitative analysis shows that the PD-CSE technique is more sensitive, but other authors have not found significant differences between the aforementioned techniques. Therefore, we performed a quantitative analysis in this study that aims to measure differences in the quality of the images obtained with both techniques.MethodsWe compared the PD-CSE and PD-FSE techniques by quantitatively analysing the obtained proton density images: the area shown, as well as the brightness and lesion contrast of the obtained image.A set of 100 images from 50 patients thought to contain meniscal tears of the knee were selected. These 100 images were obtained from all individuals using both the PD-CSE and PD-FSE techniques. The images were processed using software developed in Delphi. In addition to these quantifications, three physicians, who are specialists in radiology and capable of analysing magnetic resonance (MR) images of the musculoskeletal system, qualitatively analysed the diagnostic sensitivity of both techniques.ResultsOn average, samples obtained via the PD-CSE technique contained 22% more pixels in the lesion area. The contrast differed by 28%, and the brightness differed by 31%. The two techniques were correlated using Student’s t-test, which showed a statistically significant difference. The specialists detected meniscal tears in 30 of the images obtained via the PD-CSE technique, while only 72% of these cases were detected via the PD-FSE technique.ConclusionsThe PD-CSE technique was shown to be superior to PD-FSE for all of the evaluated properties, making its selection preferable.

Virtual Environment to Aid the Assessment of Basic Math Concepts in Children with ADHD

The Attention Deficit Hyperactivity Disorder (ADHD) is the most common disorder among children in the school. Children with ADHD have more difficulty learning the discipline of mathematics. Recent studies showed that the use of computer games as a tool to aid evaluation of mathematical concepts can provide twice more solutions to problems than conventional methods. Several studies also showed that the colors can significantly affect the attention of children with ADHD. Therefore, this paper describes the development of the computerized game with red-green axis colors to help the assessment the initial concept of math in the children with ADHD. The game developed was produced using Blender 3D graphical tool. The developed game was validated by math teachers. They evaluated if the concept of math were presented clearly and objective. The game also was evaluated by professionals on software development process which assessed the functional requirements. The developed game has criteria recommended by APA (American Psychological Association) to retain the attention of hyperactive and allow the evaluation of their actual knowledge of math concepts.

Proposal of a magnetic resonance technique for the evaluation of the calcaneofibular ligament minimizing false positive results.

BackgroundMagnetic resonance (MR) techniques used to detect lesions of the ligament complex for articulation of the ankle lack the desired accuracy for the study of the calcaneofibular ligament (CFL). The lack of sensitivity of the conventional techniques is due to variations in the dimensions of the CFL. The best results are obtained when the image plane is oriented parallel to the ligament. This study aims to develop a model that addresses the width, length and angle parameters of the CFL and the orientation of the MR image plane, and thus determine a technique in the oblique transversal plane with the foot in anatomical flexion, that is adequate for the majority of patients.MethodTo determine this orientation and adapt it to the majority of people, images of the articulation of the ankle in the 3D isotropic, volumetric, sagittal plane of 100 volunteers were taken using the MR technique. None of the volunteers had a clinical history of ligament lesions, serious pathologies, or surgeries. A measurement of the length, width, and angle of the CFL relative to the sole of the foot was performed using the MR tools. A virtual model was developed that simulated the visualization of the CFL in the oblique transversal image plane from 35° to 45° using the CFL dimensions of 100 volunteers. The comparison of the simulations with the reconstructed images validated the model and permitted the calculation of the agreement and sensitivity of each technique in the detection of the complete CFL.ResultsUsing the simulator, it was possible to obtain the limit angle for complete CFL visualization as a function of its dimensions for any angle of the oblique transversal image plane of the MR.ConclusionThe results suggest that a single image acquisition technique in the oblique transversal plane at 38° with the foot in anatomical flexion would serve the majority of patients.

Quantificação do Efeito de Exercício Físico sobre a Concentração do Hiperativo

Recognized as a great promoter of health, the physical activity includes beneficial changes such as reduced risk of chronic degenerative diseases, bone loss and cardiovascular disease. Recently, another aspect has gained enough prominence, it is the improvement of cognitive function, several studies have shown that physical exercise enhances and protects brain function. Thus, this study aimed to quantify, using a Computer Game, the effect of intense physical activity on the concentration of students with evidence of “Attention Deficit Hyperactivity Disorder.” The sustained attention was quantified by applying a computerized test of attention from an intense aerobic activity for five minutes.

Modelagem Virtual para Projetar Dispositivos de Reabilitação

Nowadays in the industry, the 3D modeling is used to foresee possible errors, to calculate their structures and to reduce production costs. However the tools used in the industry many times can’t be applied in therapeutic treatment because don’t simulate satisfactorily the physics and the moves of the patient. In this work, it was used the Blender modeling tool to project two devices. One of them was destined to stimulate in the hydrotherapy the motor control of trunk in children with cerebral paralysis. The other 3D model was projected to stimulate children with Down Syndrome to creep. The modeling allowed foreseeing the children’s behavior with different ages, different morphologies, many levels of engagement and to detect errors before the prototypes were constructed. The devices had been developed and tested for special children, and they were considered suitable to the physical rehabilitation.

Ambiente virtual para a auxiliar a concentração de crianças com hiperatividade

It is well known that children with hyperactivity usually can’t execute some tasks due to the lack of concentration; therefore, in order to increase such children’s concentration, we have developed a computerized game, with a story based on an old pirate who travels several islands and dangerous seas to find a lost treasure. To begin this adventure the child should understand the hints showed by the characters of game. The Blender graphical tool was used to model the objects of the scenes, the characters, and so provided good interactivity, through their game engine. The objects of the scenes together with the sound effects allowed a completed immersion of the player in the environment. The developed game attends the APA (American Psychiatry Association) recommendations; therefore, the levels are shorter compared to those of similar games. Furthermore, the children are rewarded for each executed task and not for each level; the kind and the rhythm of the tasks are frequently changed and some sensorial methods considered in the game may exert the children’s memorization and concentration in a reduced visual field. The game was appraised by a games specialist, who considered as attractive as other similar games. It also has been submitted to a neurologist, who considered the game appropriated to improve the concentration of the children with hyperactivity. The game was tested with 10 children with hyperactivity, who demonstrated interest in playing the game several times. It was noted that the children who finished the game in the first attempt had experience with computerized games. The children who didn’t finished after the first attempt, manifest interest trying again.