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Worfolk, Ralph. "Ocular-motor control in congenital nystagmus." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310353.
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Kißler, Johanna. "Neuropsychological and ocular motor studies of schizophrenia /." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10118099.
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Gray, Lyle S. "Reflex and volitional control of ocular motor function." Thesis, Glasgow Caledonian University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385047.
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Akin, Faith W., and K. Mills. "Auditory, Vestibular, and Ocular Motor Consequences of Blast Exposure." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/2436.
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Farber, Robert H. "Ocular motor system functioning in obsessive-compulsive disorder and Tourette syndrome /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9917950.
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Schultz, Kevin P. "Exploration of the crosslinks between saccadic and vergence eye movement pathways using motor and visual perturbations." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2010. https://www.mhsl.uab.edu/dt/2010p/schultz.pdf.
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Fanti, Juliana Roberta. "Programa de treinamento para utilizar rastreador ocular por aluno com doença neuromuscular /." Marília, 2019. http://hdl.handle.net/11449/181041.
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Orientadora: Lígia Maria Presumido BraccialliBanca: Rita de Cássia Tibério Araújo
Banca: Gerusa Ferreira Lourenço
Resumo: Cada vez mais, o computador tem sido um recurso de tecnologia assistiva utilizado para possibilitar a participação de alunos com deficiência física severa nas escolas comuns. Porém, há a necessidade de prescrição de dispositivos de acesso ao computador, não convencionais, para que esses alunos consigam utilizar o computador com independência e autonomia. Considerando os comprometimentos motores e a fadiga muscular decorrentes das doenças neuromusculares, um dispositivo que ofereça o acesso e uso do computador com menor demanda muscular e menos gasto energético é essencial para esse alunado. Dentre os dispositivos ofertados, o rastreador ocular vem se destacando como um recurso de acesso eficaz para pessoas com deficiência física severa, entre elas as decorrentes de doenças neuromusculares. Contudo, o uso desse dispositivo demanda de um controle oculomotor preciso para que atinja os objetivos a ele alçados. O controle oculomotor, para tal finalidade, se encaixa na teoria da aprendizagem motora, a qual não pode ser diretamente observada, mas pode ser inferida pela melhora no desempenho motor. O objetivo desse estudo foi analisar o efeito de um programa de treinamento para uso de rastreador ocular no desempenho motor de crianças com doenças neuromusculares. Caracterizou-se por uma pesquisa experimental com delineamento de sujeito único do tipo A-B-A. Participou desse estudo uma aluna com 9 anos, diagnóstico de distrofia muscular. As variáveis pesquisadas foram acurácia, tempo de... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Increasingly, the computer has been a feature of assistive technology used to enable the participation of students with severe physical disabilities in ordinary schools. However, there is a need to prescribe non-conventional computer access devices so that these students can use the computer with independence and autonomy. Considering motor impairments and muscle fatigue due to neuromuscular diseases, a device that provides access and use of the computer with lower muscle demand and less energy expenditure is essential for this student. Among the devices offered, the ocular tracer has been highlighted as an effective access resource for people with severe physical disabilities, including those due to neuromuscular diseases. However, the use of this device requires precise oculomotor control in order to achieve the objectives set forth. Oculomotor control, for this purpose, fits the theory of motor learning, which can not be directly observed, but can be inferred by the improvement in motor performance. The objective of this study was to analyze the effect of a training program for use of ocular tracer on the motor performance of children with neuromuscular diseases. It was characterized by an experimental research with a single subject design of type A-B-A. A 9-year-old female student with a diagnosis of muscular dystrophy participated in this study. The variables studied were accuracy, reaction time, movement time and error. To evaluate the motor performance, the software Di... (Complete abstract click electronic access below)
Mestre
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Polido, Graziela Jorge. "Desempenho visual, cognitivo e motor de crianças com atrofia muscular espinhal." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5170/tde-27092018-085056/.
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A atrofia muscular espinhal (AME) é uma doença rara e neurodegenerativa, que afeta crianças e adultos. Gera atrofia muscular, prejudica os movimentos voluntários e, em muitos casos, dificulta a comunicação oral. Esta dissertação é composta por dois artigos. O Estudo 1 objetivou revisar a literatura sobre o desenvolvimento cognitivo de pessoas com AME. O Estudo 2 objetivou avaliar o desempenho visual, cognitivo e motor de crianças com AME tipo 1 (AME-I). O primeiro estudo foi uma revisão sistemática, com levantamento dos últimos 25 anos (de 1992 a 2017) nas bases de dados PUBMED/Medline, Web of Science e Scielo. Os descritores utilizados foram: spinal muscular atrophy e cognition. O estudo 2 consistiu na avaliação de 24 crianças, divididas em dois grupos: 12 crianças com AME-I (3 a 9 anos, 9 meninos e 3 meninas) e 12 crianças saudáveis, pareadas por idade e sexo. As 24 crianças responderam a quatro tarefas de associação de figuras, com dificuldade crescente. As respostas foram detectadas por meio de um rastreador de olhar. Para o primeiro estudo foram localizados 43 artigos, desses, nove foram selecionados, de acordo com os critérios de inclusão e exclusão. O estudo apontou que o desempenho cognitivo de crianças com AME é heterogêneo. Três artigos indicaram que essas crianças têm desempenho cognitivo normal, três artigos indicaram que há atraso e outros três estudos relataram desempenho acima da média. De modo geral, as crianças com maior fraqueza muscular (AME-I) apresentaram maior comprometimento e estudos mais recentes detectaram esse atraso. O segundo estudo descreveu pior desempenho do grupo AME-I, em relação ao grupo controle (maior número de erros e maior tempo para execução das tarefas). Concluímos que, até o momento, poucos estudos investigaram aspectos cognitivos em crianças e adolescentes com AME. O desenvolvimento cognitivo de crianças com AME deve ser acompanhado, principalmente em crianças com AME-I. É necessário avaliar o desempenho cognitivo e, se necessário, propor intervenções para pessoas com AME. O desenvolvimento cognitivo adequado facilita a autonomia e interação. Os rastreadores de olhar podem estimular e aprimorar esse repertórioSpinal muscular atrophy (SMA) is a rare and neurodegenerative disease, affecting children and adults. SMA causes muscular atrophy and weakness, and, in many cases, impairs the development of oral communication. This dissertation is composed of two articles. Study 1 aimed to review the literature about the cognitive development of people with SMA. Study 2 aimed to evaluate the visual, cognitive and motor performance of children with SMA type 1 (SMAI). Study 1 reviewed the findings of the last 25 years (1992 to 2017), in PUBMED/Medline, Web of Science and Sicelo databases. The descriptors were: spinal muscular atrophy and cognition. Study 2 consisted of the evaluation of 24 children divided into two groups: 12 children with SMA-I (3 to 9 years of age, 9 boys and 3 girls) and 12 healthy children, matched by age and sex. The 24 children performed four figure-association tasks, with increasing difficulty. Responses were detected by an eye tracking device. For the first study, 43 articles were identified and nine were selected because they met the inclusion and exclusion criteria. The study pointed out that the cognitive performance of children with SMA is heterogeneous. Three articles indicated that children with SMA had normal cognitive performance, three observed delayed performance and three studies described cognitive performance as above average. In general, samples with children with more severe muscular weakness (SMA-I) showed some cognitive impairment and more recent studies detected this delay. The second study described poorer performance of the SMA-I group, compared to the control group (more errors and longer times). In conclusion, few studies investigated cognitive outcomes in children and adolescents with SMA. The cognitive development of children with SMA should be followed, especially children with SMA-I. More studies should evaluate and, if necessary, intervene to prevent cognitive impairment in people with SMA. The proper cognitive development facilitates autonomy and interaction. The eye tracker can stimulate and improve their repertoire
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Anil, Kumar Amrutur Saryanarayana. "Clinical and ocular motor characterisation of infantile and acquired nystagmus using eye movement recordings." Thesis, University of Leicester, 2015. http://hdl.handle.net/2381/32220.
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Our aim was to characterise the ocular motor abnormalities in infantile (IN) and acquired nystagmus (AN) using eye movement recordings in order to improve diagnosis and understanding of these diseases. The first aim was to compare a genetically homogenous idiopathic IN group (FRMD7-IN) with albinism associated IN. The second aim was to investigate acquired pendular nystagmus (APN) due to MS along with other ocular motor abnormalities, in relation to disease severity and MS subtype. Eye movements were recorded in all IN and AN participants (n=117). Ocular motor characteristics of the nystagmus were analysed. Other clinical features were compared including strabismus, stereopsis and anomalous head posture (AHP) in IN and the disability score and MS subtype in MS. FRMD7-IN contained higher proportions of pendular waveform compared with albinism. Nystagmus frequency was significantly lower in albinism compared with FRMD7-IN. Strabismus and AHP were more frequent in albinism, and stereopsis was worse compared with FRMD7-IN. In MS APN coexisted with various other ocular motor deficits including gaze-evoked nystagmus, internuclear ophthalmoplegia and square wave jerks although the occurrence of these was not related to MS severity or subtype. The APN was dysconjugate mainly due to a difference in amplitude between the two eyes rather than frequency. There was no clear change in APN parameters with MS severity or subtype. We describe for the first time the differences in nystagmus characteristics associated with albinism and FRMD7- IN which may be useful information in the future elucidation of mechanisms underlying the nystagmus and also in diagnosis. In MS we confirm that APN is mainly dysconjugate due to amplitude and can co-exist with various ocular motor abnormalities. Eye movement recordings can assist in differentiating various ocular motor abnormalities in IN and AN that are difficult to characterise on clinical examination.
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Northway, Nadia. "Psychophysical and ocular motor aspects of visual processing in dyslexics with Meares Irlen Syndrome." Thesis, Glasgow Caledonian University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404683.
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Wong, Agnes Ming-Fong. "Three dimensional disorders of gaze and binocular alignment after brainstem and ocular motor nerve lesions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ63735.pdf.
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Han, Ying. "Effects of eye and neck muscle proprioception on ocular motor control in normal and strabismic subjects /." Stockholm, 1998. http://diss.kib.ki.se/search/diss.se.cfm?19980605han.
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Farooq, Shegufta Jabeen. "Torsional optokinetic nystagmus : response characteristics measured in the normal population and patients with ocular motor disorders." Thesis, University of Leicester, 2009. http://hdl.handle.net/2381/7364.
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This thesis presents the first detailed study of the torsional optokinetic nystagmus (tOKN) response in the normal population and in patients with oculomotor disorders. The effects on the tOKN response of: (i) stimulus velocity, (ii) stimulus area, and (iii) aging, were investigated in the normal population. The tOKN response was also evaluated in patients with long standing oculomotor disorders, namely strabismus and infantile nystagmus. Torsional OKN responses were recorded using infrared video-oculography and were elicited with volunteers fixating the centre of a large-field rotating sinusoidal grating pattern. Torsional OKN responses were present in all normal young volunteers (n=20) to stimuli rotated in clockwise and anticlockwise directions, and a linear relationship was observed between log stimulus velocity and tOKN slow phase velocity. Torsional OKN also showed brisk responses to peripheral field stimulation in the same subjects. The first report of a significant increase with age in the proportion of absent tOKN responses is also described in normal subjects aged between 19-72 years (n=30). The tOKN response was investigated for the first time in strabismic patients (n=16), comparing horizontal and vertical OKN responses, and also in patients with infantile nystagmus (n=16). OKN responses from strabismus patients demonstrated consistent asymmetry in horizontal and vertical directions. However, a significantly higher incidence of absent tOKN responses in both intorsion and extorsion directions were observed in comparison to controls. Torsional OKN was present in 3 of 16 patients with infantile nystagmus. Torsional OKN is a well developed reflex in the normal population with the capacity to respond in proportion to stimulus velocity and area of stimulation. However, the tOKN response is dramatically affected by (i) the effects of aging, (ii) by the interruption of binocular visual development in patients with strabismus, and (iii) by the presence of infantile nystagmus.
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Davison, Ryan C. "The behavior of oculomotor neurons during conjugate and disconjugate eye movements." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2009r/davison.pdf.
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Swait, Gabrielle. "The effect of neck pain on performance in tests of proprioception, cervico-cephalic kinesthesia and ocular motor function." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5276/.
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This work investigated relationships between neck pain, cervical proprioception and ocular motor performance. Systematic literature reviews identified moderate quality evidence for greater cervical joint positioning errors (JPE) in the transverse plane among participants with whiplash, but low-to-very low quality evidence for participants with non-traumatic neck pain, and for other cervical and ocular tests. Limited low quality evidence indicated little correlation between performance across tests, questioning their construct validity for cervical proprioception. Test-retest studies established adequate intra-examiner reliability of a smooth-pursuit (SPNT) test, a novel, non-predictable ocular tracking test and of cervical JPE and cervico-cephalic kinesthesia tests. A cross-sectional study found impaired non-predictable ocular tracking performance in mechanical neck pain, compared with healthy participants. The construct validity of this, and of existing tests, was evaluated by examining convergence of correlation in their performance. In healthy participants, convergence between cervical JPE, cervico-cephalic kinesthesia and ocular tracking tests, indicated common neurological processes. In the neck pain group there was convergence only between the cervico-cephalic kinesthesia and ocular tracking tests. A theoretical model suggested that impaired cervical proprioception or cognitive functions underlie deficits in neck pain, while adaptations in vestibular gain or efference copy underlie the absence of impairment in the cervical JPE test.
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Van, Wyk Yolanda. "Verbetering van visueel–motoriese integrasie by 6– tot 8–jarige kinders met Aandaggebrekhiperaktiwiteitsindroom / van Wyk J." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7314.
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The visual system and good ocular motor control play an important role in the effective
development of gross motor, sport, fine motor and academic skills (Erhardt et al., 1988:84;
Desrocher, 1999:36; Orfield, 2001:114). Various researchers report a link between ocular motor
problems and attention–deficit hyperactivity disorder (ADHD) (Cheatum & Hammond,
2000:263; Farrar et al., 2001:441; Gould et al., 2001:633; Armstrong & Munoz, 2003:451;
Munoz et al., 2003:510; Borsting et al., 2005:588; Hanisch et al., 2005:671; Mason et al.,
2005:1345; Loe et al., 2009:432). A few studies were carried out to analyse the links between
ADHD and ocular motor control with regard to matters like visual attention, visual perception
and ocular motor control like eye movement outside the normal fixation point, but no studies
have been reported on the status of the ocular motor control of South African populations, and
the effect of visual–motor intervention on the ocular motor control or visual–motor integration of
learners with ADHD.
The aim of the study was twofold, namely firstly to determine the ocular motor control functions
and status of visual–motor integration of a selected group of 6– tot 8–year–old learners with
ADHD in Brakpan, South Africa, while the second aim was to determine whether a visualmotor–
based intervention programme can improve the ocular motor control and status of the
visual–motor integration of a selected group of 6– to 8–year–old learners with ADHD in Brakpan,
South Africa.
Statistica for Windows 2010 was used to analyse the data. The Sensory Input Screening
measuring instrument and the Quick Neurological Screening Test II (QNST–II) were used to
assess the ocular motor control functions (fixation, ocular alignment, visual tracking and
convergence–divergence), while the Beery Developmental Test of Visual–Motor Integration
(VMI–4de weergawe) was used to determine the status of the learners’ visual–motor integration
(VMI), visual perception (VP) and motor coordination (MC). The Disruptive Behaviour Scale, a
checklist for ADHD (Bester, 2006), was used as measuring instrument to identify the learners
with ADHD.
Fifty–six learners (31 boys, 25 girls, with an average age of 7,03 years +0,65) participated in the
pre–test and were divided into an ADHD (n=39) and a non–ADHD (n=16) group for aim one.
Two–way tables were used to determine the percentage of ocular motor control deficits in the learners with and without ADHD, and an independent t–test was used to analyse the visual–motor
integration of these learners. The Pearson Chi–squared test was used to determine the practical
significance of differences in VMI and VP (d>0,05). The results of the study reveal that the
majority of learners displayed ocular motor control deficits, regardless of whether they were
classified with ADHD or not. The biggest percentage of learners fell into Class 2 (moderate
deficits), particularly with regard to horizontal (68,57%; 52,63%; w=0,16) and vertical tracking
(65,71%; 73,68%), as well as convergence–divergence (80%; 78,95%; w=0,11). However, it
appears that ADHD learners experience more serious problems (Class 3) with visual tracking
than learners without ADHD (both eyes: 22,86%; compared to 10,53% (w=0,22); right eye:
11,43% compared to 0% (p=0,05; w=0,34); left eye: 14,29% compared to 0% (p=0,02; w=0,38)).
Learners with and without ADHD displayed a practically significant difference with respect to
visual perception (d=0,37) and motor coordination (d=0,5) compared to learners without ADHD
(who achieved better results).
For aim 2 the subjects were divided into three groups. A pre–test–post–test design compiled from
an availability sample of three groups (intervention group with ADHD (n=20); control group
with ADHD (n=10) and control group without ADHD (n=17)) was used for this part of the
study. The intervention group participated in a nine–week (3x/week and for 45 minutes) visualmotor–
based intervention programme in which the ocular motor control functions section was
applied for about 5 minutes per learner. Forty–seven learners (25 boys and 22 girls) with an
average age of 6,95 years (+0,69) constituted the experimental group, while a control group with
ADHD with an average age of 7,2 years (+0,79) and a control group without ADHD with an
average age of 7,12 years (+0,60) did not receive any intervention and just participated in the
pre– and post–test opportunity. A two–way cross–tabulation table was used to determine the
changes in ocular motor control functions. These results mainly revealed that practically
significant changes occurred in all three groups, be it improvement or deterioration in the various
classes of ocular motor control. It appears that as far as horizontal and vertical visual tracking is
concerned, and with convergence–divergence, more subjects were moved back from Class 3
(serious cases) to Class 1 (no deficits) and 2 (moderate deficits) in particular than in the other
two groups that had received no intervention. Independent t–testing was used to analyse
intragroup differences in the visual–motor integration subdivisions, while a covariance analysis
(ANCOVA) (corrected for pre–test differences) was used to determine adjusted average post–test
difference values. These results revealed that the motor coordination of the intervention group
improved more than that of the control group with ADHD (p=0,18). This can lead to the
conclusion that the intervention programme did have an effect on this specific skill.
Abstract The overall indications of the results are that learners with ADHD have a general tendency to
achieve poorer results in ocular motor control tests and with skills involving visual–motor
integration, visual perception and motor coordination than learners without ADHD. Although
only a minor improvement was identified in the experimental group after participation in the
intervention programme, it is recommended with regard to motor coordination in particular that a
similar programme be compiled for ADHD learners that focuses more specifically on the ocular
motor control needs of each learner, and that it be presented on a more individual basis in order
to accomplish greater improvement.Thesis (M.A. (Kinderkinetics))--North-West University, Potchefstroom Campus, 2012.
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Jasse, Laurence. "Troubles visuels chroniques, nystagmus pendulaire et oscillopsie dans la sclérose en plaques." Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00666004.
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Les manifestations neuro-ophtalmologiques, observées dans la sclérose en plaques sont parfaitement déterminées à l'heure actuelle. Cependant, l'aspect chronique des troubles visuels résultants n'est pas toujours précisément évalué, or de telles lacunes sont un frein à leur prise en charge. Dans une première partie, les caractéristiques des troubles visuels chroniques ont été mesurées. Il s'agissait de quantifier le pourcentage de plaintes visuelles chroniques chez des patients atteints de sclérose en plaques puis de mesurer le degré d'intensité des troubles visuels chroniques, de déterminer leurs origines physiopathologiques et de rendre compte de leur retentissement sur la qualité de vie des patients se plaignant de troubles chroniques. Les voies visuelles afférentes étaient altérées dans 68% des cas. Des troubles oculomoteurs étaient fréquemment observés (89%) dont le nystagmus pendulaire (28%), source de gêne visuelle. Dans une seconde partie, nous nous sommes donc intéressés au nystagmus pendulaire et à sa conséquence fonctionnelle, l'oscillopsie, afin de proposer une prise en charge spécifique. Néanmoins, les mécanismes de ce nystagmus ne sont pas encore bien définis. Il était donc important de développer une hypothèse explicative à partir de l'observation de deux cas particuliers de nystagmus monoculaire et de démontrer que le nystagmus pendulaire de la sclérose en plaques est à distinguer du nystagmus pendulaire du tremblement oculopalatin, souvent confondus. Enfin, nous proposons une méthode évaluant la détection du mouvement (par stimuli de contraste asservis au regard) ainsi qu'un protocole de stimulation optocinétique tentant de réduire ce symptôme
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Paeye, Céline. "Morphogénése et variabilité au sein du système oculo-moteur." Thesis, Lille 3, 2012. http://www.theses.fr/2012LIL30011/document.
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Un vaste corpus de recherches computationnelles est consacré à l’analyse du contrôle moteur. Cette approche, qui étudie l’adaptation saccadique comme un modèle d’apprentissage sensori-Moteur, invoque des mécanismes spécialisés dans la calibration de gains internes ou l’optimisation de fonctions de coûts. Cette thèse propose une explication différente de l’apprentissage oculo-Moteur en montrant que les distributions d’amplitudes saccadiques peuventêtre modifiées par leurs conséquences.D’abord, nous avons manipulé la médiane du gain saccadique. Nous avons éliminé l’erreur rétinienne post-Saccadique et présenté des stimulus sonores ou visuels après les saccades répondant à des critères d’amplitude. Ce renforcement opérant a induit des changements de gain similaires à l’adaptation saccadique obtenue par le paradigme conventionnel de double saut. Puis nous avons montré qu’une part de la variabilité peut être contrôlée par un apprentissage opérant. Différents niveaux de variabilité de gain ont été renforcés avec un son. Les changements obtenus suggèrent que la variabilité ne résulte pas uniquement d’un bruit interne. Enfin, dans une tâche de recherche visuelle, la présentation de la cible en guise d’agent renforçateur a aussi permis d’augmenter puis de réduire la variabilité des amplitudes saccadiques. Cela signifie que voir lacible est une conséquence qui contrôle (en partie) les propriétés des saccades.Ces études montrent qu’un processus général d’apprentissage, qui dépend des conséquences fonctionnelles des saccades, peut guider les changements de leur amplitude. Cela pourrait s’avérer crucial pour maintenir la précision des saccades tout au long de la vieA large body of computational research has been devoted to understanding motor control.This approach, using saccadic adaptation as an example of sensorimotor learning, postulates specialized mechanisms responsible for a motor calibration or optimization processes of cost functions. This thesis dissertation provides an alternative view of oculomotor learning byshowing that saccadic amplitude distributions can be altered by their own consequences.First we manipulated saccadic gain medians. We eliminated the postsaccadic retinal error (either by extinguishing the target during the saccade or by stabilizing its image on the fovea) and provided auditory or visual consequences after the saccades meeting amplitude criteria. This reinforcement procedure could induce gain changes similar to saccadic adaptation obtained via a conventional double-Step paradigm.Then we showed that part of saccadic amplitude variability may be controlled by operant learning. Saccadic gain distributions were reinforced with a tone depending on variability criteria.Our data suggested that oculomotor variability may not result solely from an internal randomnoise. Finally we designed a new paradigm involving a visual search task in which presenting atarget was effective to reinforce various saccadic amplitude variability levels. This means that in real life, seeing the target is a consequence controlling (at least in part) saccadic properties.These results show that a general operant learning process, depending on the functional consequences of eye movements, can guide changes in saccadic amplitude. This may be critical to maintain saccadic accuracy during the lifespan
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Lukásová, Katerina. "Alterações fonológicas e motoras na dislexia de desenvolvimento." Universidade Presbiteriana Mackenzie, 2007. http://tede.mackenzie.br/jspui/handle/tede/1602.
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Previous issue date: 2007-02-06Dyslexia is a difficulty to acquire fluent reading and writing and the causes of this deficit are the object of an intense research. Some of the aspects of the deficit stem from impairment in phonological, motor and visual processing. Through the assessment of these impairments,the core reading deficit can be better understood and new clinical and teaching approaches developed. One of the ways to assess the cognitive processes involved in reading is through register of eye movements during reading since it offers us precise measures like number of fixations and gaze duration. This study aims to assess phonological, motor and reading skills of dyslexic children and normal readers. We assessed 10 children diagnosed for dyslexia and 10 controls with normal readings skills. Controls were matched for sex, age, and school grade. All the children completed a large set of assessment tasks: the Phonological Awareness Test, Perdue Pegboard Test, Eye Pursuit Task, Predictive Saccade Task, Word, Non-real Word and Syllable Reading Task. The result showed impairment for the dyslexic children in all of three assessed skills. In the Phonological Awareness Test, a lower score was found for the syllable and phoneme manipulation. In the motor tasks, a different pattern of eye movement was registered for the leftward saccades, but no differences were observed for the Perdue Pegboard Test. In the reading task, dyslexic children showed longer gaze time and more fixations on each word. No interaction was found for group and characteristics of the stimuli, such as frequency, length and regularity of the words. This indicates that in reading, the eye movements pattern of dyslexic children is similar to the controls. The results showed a presence of phonological and motor deficit in dyslexic children. Further studies are necessary to investigate the correlation of phonological and motor deficit and its specificity for dyslexia.
Dislexia é uma dificuldade de automatizar as habilidades de leitura e escrita, e suas causas estão sendo intensamente estudadas. Alguns dos fatores apontados como subjacentes da dificuldade na leitura são déficits nas habilidades fonológicas, motoras e visuais. Por meio de avaliação dessas manifestações comportamentais, pode-se compreender melhor o déficit e, por conseqüência, ajudar na descoberta de princípios clínicos e pedagógicos mais adequados para os seus portadores. Um dos meios de acessar o processamento de leitura é através do registro de movimentos oculares, que utiliza medidas mais precisas, tais como: número e tempo total de fixações. O presente trabalho objetivou avaliar habilidades fonológicas, motoras e de leitura em crianças com dislexia e crianças entendidas como "bons leitores". Foram avaliadas 10 crianças com dislexia e 10 controles pareados em função de sexo, idade e escolaridade. As crianças foram avaliadas com uma extensa bateria de testes composta por: Teste de Consciência Fonológica, Teste de Motricidade Perdue Pegboard, Teste de Seguimento Ocular, Teste de Sacada Preditiva, Teste de Leitura de Palavras, Teste de Leitura de Pseudopalavras e Teste de Leitura de Sílabas. Os resultados demonstram desempenhos inferiores no grupo de disléxicos em três domínios investigados: fonológico, motor e de leitura. Para habilidades fonológicas, foi encontrado pior desempenho dos disléxicos no nível de manipulação silábica e fonêmica. Em relação às habilidades motoras, foi encontrada alteração em tarefas de movimento ocular relacionada com o lado esquerdo, mas não foi encontrada diferença no teste de Motricidade Perdue Pegboard. Nas habilidades de leitura com o registro de movimento ocular foram encontrados maiores tempos e números de fixações em cima da palavra. Não foi encontrada interação do grupo com as características psicolingüísticas, tais como freqüência, regularidade ou comprimento da palavra. Isso indica não haver diferença no padrão de movimentos oculares em disléxicos durante a leitura. Os resultados indicam a presença do déficit fonológico e motor nos disléxicos. Outros estudos são necessários para investigar correlação entre ambos os déficits e a especificidade com a dislexia.
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Castro, Stella Maris da Costa e. 1960. "Função visual e motora ocular na esclerose múltipla." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310194.
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Orientador: Keila Miriam Monteiro de CarvalhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: A esclerose múltipla é uma doença crônica imunomediada do sistema nervoso central, caracterizada por inflamação, desmielinização e lesão axonal na fase inicial, e desmielinização crônica, degeneração progressiva e perda axonal, atrofia cerebral e gliose na fase crônica. O acometimento do sistema visual e motor ocular são manifestações comuns da doença. O objetivo desse estudo foi observar as alterações relacionadas das funções visuais no período remissivo da doença e sua correlação com as imagens da ressonância magnética. Foram realizadas a avaliação da acuidade visual, do campo visual central computadorizado, da visão cromática e da sensibilidade ao contraste em 48 pacientes com esclerose múltipla recidivante-remitente e em 25 controles. O evento anterior de neurite óptica aguda foi utilizado para classificar os pacientes: 26 com história positiva e 22 com história negativa. A avaliação clínica dos movimentos oculares foi realizada em 60 pacientes e 35 controles. O subgrupo com história de neurite óptica apresentou pior resultado (p<0,05) em todos os testes quando comparado ao grupo controle; o subgrupo sem história de neurite óptica apresentou pior resultado na perimetria estática e na visão de cores. Os dois subgrupos não diferiram entre si nos resultados dos testes visuais. Na avaliação comparativa entre as lesões observadas nas radiações ópticas de 29 pacientes e os índices da perimetria estática, houve associação entre lesões mais extensas e piores índices do campo visual. Na análise dos movimentos oculares, a falha do cancelamento do reflexo vestíbulo ocular, a dismetria sacádica e a presença de movimentos corretivos durante o acompanhamento ocular uniforme, foram as alterações mais freqüentes. O questionário de função visual e o suplemento de itens neuroftalmológicos detectaram pior qualidade de vida visual numa amostra de 41 pacientes com esclerose múltipla em relação a 22 controles. O comprometimento da função visual e motora ocular foi frequente na esclerose múltipla no estágio recidivante-remitente mesmo fora do período agudo da doença. Foi possível observar associação entre os índices da perimetria automatizada e resultados quantitativos das imagens por ressonância magnética. Alterações dos movimentos oculares, próprias do quadro de oftalmoplegia internuclear, puderam ser associadas às lesões do fascículo longitudinal medial
Abstract: Multiple sclerosis is a chronic immune-mediated disorder of the central nervous system characterized by inflammatory demyelination and axonal injury in the early phase, as well as chronic demyelination, progressive axonal degeneration and loss, cerebral atrophy and gliosis in the chronic phase. The involvement of the visual and ocular motor systems is a common manifestation of the disease. The objective of this research was to observe the disorders related to visual functions, in the remission phase of the disease, and their correlation to magnetic resonance images. Visual acuity, central automated visual field, color vision, and contrast sensitivity were assessed in 48 relapsing remitting multiple sclerosis patients and 25 controls. The episode of acute optic neuritis was used to classify the patients: 26 with positive history and 22 without. Careful clinical observation of ocular movements was done in 60 patients and 35 controls. The subgroup with positive history of acute optic neuritis had worse results (p<0.05) compared with the control group; the subgroup with no history of optic neuritis had worse results (p<0.05) in automated perimetry and color vision. Neither of the subgroups differed between one another (p>0.05). In the comparative assessment between optic radiations lesion of 29 patients and perimetric visual fields, there was a relationship between larger lesions and worse visual fields indices. In the examination of eye movements, the failure of the cancellation of vestibular ocular reflex and the presence of corrective movements during pursuit were the most frequent abnormalities. The National Eye Institute 25-Item Visual Functioning Questionnaire and their 10-Item Neuro-Ophthalmic Supplement scores were lower in 42 multiple sclerosis patients compared with 22 controls. The involvement of the visual and ocular motor function was frequent in multiple sclerosis patients in the relapsing remitting phase, even outside of the acute phase of the disease. It was possible to observe a relationship between visual field indices and quantitative measurements of magnetic resonance images. Abnormalities of the ocular movements, suggestive of internuclear ophtalmoplegia were associated with lesions of the medial longitudinal fasciculus
Mestrado
Ciencias Biomedicas
Doutor em Ciências Médicas
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Akin, Faith W., Owen D. Murnane, and Tina M. Proffitt. "The Effects of Click and Tone-Burst Stimulus Parameters on the Vestibular Evoked Myogenic Potential (vemp)." Digital Commons @ East Tennessee State University, 2003. https://dc.etsu.edu/etsu-works/1790.
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Vestibular evoked myogenic potentials (VEMP) are short latency electromyograms (EMG) evoked by high-level acoustic stimuli and recorded from surface electrodes over the tonically contracted sternocleidomastoid (SCM) muscle and are presumed to originate in the saccule. The present experiments examined the effects of click and tone-burst level and stimulus frequency on the latency, amplitude, and threshold of the VEMP in subjects with normal hearing sensitivity and no history of vestibular disease. VEMPs were recorded in all subjects using 100 dB nHL click stimuli. Most subjects had VEMPs present at 500, 750, and 1000 Hz, and few subjects had VEMPs present at 2000 Hz. The response amplitude of the VEMP increased with click and tone-burst level, whereas VEMP latency was not influenced by the stimulus level. The largest tone-burst-evoked VEMPs and lowest thresholds were obtained at 500 and 750 Hz. VEMP latency was independent of stimulus frequency when tone-burst duration was held constant.
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Akin, Faith W., Owen D. Murnane, Peter C. Panus, Stacy K. Caruthers, Amy E. Wilkinson, and Tina M. Proffitt. "The Influence of Voluntary Tonic Emg Level on the Vestibular-Evoked Myogenic Potential." Digital Commons @ East Tennessee State University, 2004. https://dc.etsu.edu/etsu-works/1789.
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Vestibular-evoked myogenic potentials (VEMPs) are proposed as a reliable test to supplement the current vestibular test battery by providing diagnostic information about saccular and/or inferior vestibular nerve function. VEMPs are short-latency electromyograms (EMGs) evoked by high-level acoustic stimuli and recorded from surface electrodes over the tonically contracted sternocleidomastoid muscle. VEMP amplitude is influenced by the EMG level, which must be controlled. This study examined the ability of subjects to achieve the EMG target levels over a range of target levels typically used during VEMP recordings. In addition, the influence of target EMG level on the latency and amplitude of the click- and tone-evoked VEMP was examined. The VEMP amplitude increased as a function of EMG target level, and the latency remained constant. EMG target levels ranging from 30 microV to 50 microV are suggested for clinical application of the VEMP.
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Sousa, Luiz Fernando de [UNESP]. "Influência de movimentos oculares sacádicos no equilíbrio postural de idosos praticantes de vôlei adaptado e idosos sedentários." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/134067.
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000856657.pdf: 192774 bytes, checksum: 46a326ffa8cbccd900545e66e13ec497 (MD5)O envelhecimento humano é marcado por diversas alterações, tanto morfológicas quanto funcionais, as quais podem resultar em um declínio das capacidades físicas, funcionais, cognitivas e de vida diária. Os idosos com perdas sensoriais significativas da visão e da propriocepção podem ter dificuldade em manter uma postura estável. Várias estruturas do sistema nervoso central compartilham envolvimento no controle do movimento ocular e postural, mas a influência dos mecanismos visuais no controle postural ainda não estão claros. Existem evidências discrepantes sobre a possibilidade de movimentos sacádicos melhorarem ou deteriorarem a estabilização postural e de que o exercício físico interfere no controle postural. O objetivo deste estudo foi determinar a influência dos movimentos oculares sacádicos horizontais de baixa e alta frequência no equilíbrio de idosos praticantes de vôlei adaptado e idosos sedentários. Foram avaliados quinze idosos praticantes de vôlei adaptado e quinze idosos sedentários. Os sujeitos realizaram três tentativas em cada condição sensorial, com duração de trinta segundos cada tentativa, na posição em pé, descalços, com base bipodal e pés na largura dos ombros sobre uma plataforma de força AMTI® que mensurou as oscilações corporais em seis condições sensoriais definidas de acordo com a superfície (base estável ou base instável) e com o estímulo visual (fixação, movimentos sacádicos lentos ou movimentos sacádicos rápidos). O olhar foi registrado por um sistema de movimentos dos olhos ASL®. Os resultados não apontaram diferenças significativas entre os grupos, mas mostraram que na base estável a oscilação corporal foi significativamente menor do que na base instável. Com relação à influência das condições visuais sobre controle postural, observamos que movimentos sacádicos de baixa e alta frequência diminuíram significativamente a oscilação corporal quando...
Human aging is characterized by several changes, both morphological as functional, which may result in a physical, functional, cognitive and daily life decline. Elderly people with significant sensory loss of vision and proprioception seem have difficulty to maintain a stable position. Many central nervous system structures share the involvement of eye and postural control, but the visual mechanism in charge of postural control are still unclear. There are conflicting evidence about the possibility of saccadic movements improve or deteriorate the postural stabilization and that physical exercise affects in postural control. The aim of this study was to determine the influence of horizontal saccadic eye movements of low and high frequency balance of elderly practitioners of adapted volleyball and sedentary elderly. Fifteen elderly practitioners of adapted volleyball and fifteen sedentary elderly were evaluated. The groups performed three trials in each sensory condition with a duration of 30 seconds each trial, in a standing position, barefoot, with bipedal base and feet shoulder-width apart on a force platform AMTI ®, which measured the corporal oscillations in 6 sensory conditions set according to the surface (stable base and unstable base) and the visual stimulus (fixation, slow saccadic movements and fast saccadic movements). The eye movement was recorded by an eye movement system ASL®. The results showed no significant differences between the groups, however, showed that in the stable base the corporal sway was significantly lower than in the unstable base. Regarding the influence of the visual conditions on postural control, that saccadic movements of low and high frequency reduced corporal sway when compared with the visual condition of fixing. We concluded that there were no significant differences in postural balance between elderly adapted volleyball practitioners and sedentary elderly, that when the support base is stable, ...
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Sousa, Luiz Fernando de. "Influência de movimentos oculares sacádicos no equilíbrio postural de idosos praticantes de vôlei adaptado e idosos sedentários /." Rio Claro, 2015. http://hdl.handle.net/11449/134067.
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Orientador: Marcos Eduardo ScheicherBanca: Fábio Augusto Barbieri
Banca: Karina Gramani Say
Resumo: O envelhecimento humano é marcado por diversas alterações, tanto morfológicas quanto funcionais, as quais podem resultar em um declínio das capacidades físicas, funcionais, cognitivas e de vida diária. Os idosos com perdas sensoriais significativas da visão e da propriocepção podem ter dificuldade em manter uma postura estável. Várias estruturas do sistema nervoso central compartilham envolvimento no controle do movimento ocular e postural, mas a influência dos mecanismos visuais no controle postural ainda não estão claros. Existem evidências discrepantes sobre a possibilidade de movimentos sacádicos melhorarem ou deteriorarem a estabilização postural e de que o exercício físico interfere no controle postural. O objetivo deste estudo foi determinar a influência dos movimentos oculares sacádicos horizontais de baixa e alta frequência no equilíbrio de idosos praticantes de vôlei adaptado e idosos sedentários. Foram avaliados quinze idosos praticantes de vôlei adaptado e quinze idosos sedentários. Os sujeitos realizaram três tentativas em cada condição sensorial, com duração de trinta segundos cada tentativa, na posição em pé, descalços, com base bipodal e pés na largura dos ombros sobre uma plataforma de força AMTI® que mensurou as oscilações corporais em seis condições sensoriais definidas de acordo com a superfície (base estável ou base instável) e com o estímulo visual (fixação, movimentos sacádicos lentos ou movimentos sacádicos rápidos). O olhar foi registrado por um sistema de movimentos dos olhos ASL®. Os resultados não apontaram diferenças significativas entre os grupos, mas mostraram que na base estável a oscilação corporal foi significativamente menor do que na base instável. Com relação à influência das condições visuais sobre controle postural, observamos que movimentos sacádicos de baixa e alta frequência diminuíram significativamente a oscilação corporal quando...
Abstract: Human aging is characterized by several changes, both morphological as functional, which may result in a physical, functional, cognitive and daily life decline. Elderly people with significant sensory loss of vision and proprioception seem have difficulty to maintain a stable position. Many central nervous system structures share the involvement of eye and postural control, but the visual mechanism in charge of postural control are still unclear. There are conflicting evidence about the possibility of saccadic movements improve or deteriorate the postural stabilization and that physical exercise affects in postural control. The aim of this study was to determine the influence of horizontal saccadic eye movements of low and high frequency balance of elderly practitioners of adapted volleyball and sedentary elderly. Fifteen elderly practitioners of adapted volleyball and fifteen sedentary elderly were evaluated. The groups performed three trials in each sensory condition with a duration of 30 seconds each trial, in a standing position, barefoot, with bipedal base and feet shoulder-width apart on a force platform AMTI ®, which measured the corporal oscillations in 6 sensory conditions set according to the surface (stable base and unstable base) and the visual stimulus (fixation, slow saccadic movements and fast saccadic movements). The eye movement was recorded by an eye movement system ASL®. The results showed no significant differences between the groups, however, showed that in the stable base the corporal sway was significantly lower than in the unstable base. Regarding the influence of the visual conditions on postural control, that saccadic movements of low and high frequency reduced corporal sway when compared with the visual condition of fixing. We concluded that there were no significant differences in postural balance between elderly adapted volleyball practitioners and sedentary elderly, that when the support base is stable, ...
Mestre
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Akin, Faith W., and Owen Murnane. "Vestibular Evoked Myogenic Potentials: Preliminary Report." Digital Commons @ East Tennessee State University, 2001. https://dc.etsu.edu/etsu-works/1792.
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Vestibular evoked myogenic potentials (VEMPs) are short-latency electromyograms evoked by high-level acoustic stimuli recorded from surface electrodes over the tonically contracted sternocleidomastoid (SCM) muscle. These responses are presumed to originate in the saccule. The purpose of this preliminary report is to provide an overview of our initial experience with the VEMP by describing the responses obtained in five subjects. Click-evoked VEMPs were present at short latencies in two normal-hearing subjects, one patient with profound congenital sensorineural hearing loss, and one patient with a severe sensorineural hearing loss due to Meniere's disease. Additionally, VEMPs were absent in a patient with profound sensorineural hearing loss following removal of a cerebellopontine angle tumor. The amplitude of the VEMP was influenced by the amount of background activity of the SCM muscle, stimulus level, and stimulus frequency. Tone-burst evoked responses showed an inverse relationship between stimulus frequency and response latency. VEMPs may prove to be a reliable technique in the clinical assessment of vestibular function.
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Souza, Ana Paula de. "Coerência, modelo oculto de Markov e Perceptron de multi-camadas em imagética motora." Universidade Federal de Minas Gerais, 2010. http://hdl.handle.net/1843/BUOS-8CLJ44.
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Brain signals and the interpretation of their patterns provide a new modality of communication: the Brain Computer Interface (BCI). BCI can use scalp potential related movement imagination to activate drive devices, not depending on the brains normal output channels: peripheral nerves and muscles. Magnitude Squared Coherence has beenused to identify the event related potential in Electroencephalogram (EEG) signals. Moreover, techniques such as Hidden Markov Model (HMM) and Artificial Neural Network (ANN with Multilayer Perceptron MLP structure) have shown promising results in classification for BCI systems. Thus, this work aims to investigate classification using HMM and ANN using features from MSC in EEG signals, for the following events: spontaneous EEG; actual index finger movement; and imaginary movement of that finger. EEGs were recorded from three normal subjects from electrodes placed according to the International 10-20 System (1st record) and 10-10 System (2nd and 3rd record). EEG was divided into trials (M - 14 seconds each) synchronized with the event. Each trial wasdivided into six segments: spontaneous EEG; EEG during visualization of red LED (Light Emitting Diode) attention; EEG during visualization of yellow LED preparation for the event; EEG during the event; spontaneous EEG; and spontaneous EEG. MSC was calculated for 12 trials and afterwards, for the maximum trials existent in each electrode.In each segment the MSC was calculated for delta band (0.1 2.0 Hz), alpha band (8.0 13 Hz) and beta band (14 30 Hz), with M=12 trials and M = maximum number of trials. The frequency band that presented the highest MSC was used as observation in HMM and as input for RNA. The average accuracy rates in the classification using HMM for M = 12were 68.5 %, 66.5 % and 67.5 %, for subjects #1, #2 and #3, respectively. For maximum M, they were 73.0 %, 70.0 % and 56.5 %. When MLP was used for classification the results for 12 trials were 64.0 %, 75.5 % and 82.0 % and, using maximum M, the accuracy rates obtained were 79.5 %, 85.5 % and 88.5 %. These results showed that the MSC technique is an efficient tool for feature extraction in EEG recording during differentevents. With these features, it was possible to classify the EEG signals using HMM and RNA, the latter presenting the best performance in event classification.Sinais cerebrais e a interpretação de padrões nos mesmos propiciam uma nova modalidade de comunicação: a Interface Cérebro Máquina (ICM). A ICM pode utilizar a atividade elétrica advinda do córtex cerebral relacionada à imaginação motora para promover o acionamento de um dispositivo, sem que haja necessariamente a integridade das vias motoras. A Magnitude Quadrática da Coerência (MSC Magnitude Square Coherence) tem sido utilizada para identificar o potencial relacionado a eventos no sinal de eletroencefalograma (EEG). Além disso, para a classificação desses eventos e aplicações em ICM técnicas como os Modelos Ocultos de Markov (Hidden Markov Model - HMM) e as Redes Neurais Artificiais (RNA) têm se mostrado promissoras. Dessa forma, esta dissertação visa investigar a classificação com HMM e RNA (na estrutura Multilayer Peceptron - MLP) utilizando como característica a MSC do sinal EEG, para os eventos:espontâneo; movimento do dedo indicador da mão esquerda; e imaginação deste movimento. Sinais EEG de três voluntários durante os eventos foram coletados com eletrodos dispostos segundo o Sistema Internacional 10-20 (1ª coleta) e Sistema 10-10 (2ª e 3ª coletas). O EEG foi dividido em trechos (M 14 segundos cada) sincronizados com oevento. Cada trecho foi fragmentado em seis segmentos: EEG espontâneo; EEG do voluntário visualizando um LED (Light Emitting Diode) vermelho atenção; EEG visualizando um LED amarelo preparação para realizar o evento; EEG durante o evento; EEG espontâneo; EEG espontâneo. Em cada segmento avaliou-se a MSC da banda delta (0,1-2 Hz), banda alfa (8-13 Hz) e banda beta (14-30 Hz), com M=12 e M=máximo número de trechos. A faixa de freqüência que apresentou maior MSC foi adotada como observação a ser utilizada no HMM e como entrada para a RNA. Os índices médios de acerto na classificação com o HMM para M=12 foram 68,5 %, 66,5 % e 67,5 %, para os sujeitos #1, #2 e #3, respectivamente. Para M máximo foram de 73,0 %, 70,0 % e 56,5 %. Quando utilizada a MLP para a classificação os índices para M=12 foram 64,0 %, 75,5 % e 82,0 % e, para M máximo 79,5 %, 85,5 % e 88,5 %. Esses achados mostram que é possível fazer modelos e classificações utilizando HMM e RNA de atividades cerebraisrelacionadas a diferentes eventos, usando a MSC do sinal de EEG. A RNA mostrou melhor desempenho do que o HMM na classificação dos eventos.
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Meindersma, Johannes. "Inferring competitiveness without price information : an application to the motor insurance portfolio of Fidelidade." Master's thesis, Instituto Superior de Economia e Gestão, 2020. http://hdl.handle.net/10400.5/20488.
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Mestrado em Actuarial ScienceEste trabalho propõe novos métodos para inferir a competitividade das apólices de seguro automóvel quando a informação disponível sobre preços é limitada. Funcionalidades do espaço dos espaços são utilizadas para filtrar o ruído das observações, introduzindo dependências temporais para a transição entre seguradoras ou para conversão. Foram recolhidos dados sobre transições entre companhias de seguros no mercado português para estimar as probabilidades de transição entre seguradoras. O modelo binomial oculto de Markov mostrou-se algo limitado ao pressupor um espaço de estados discreto. O filtro de Kalman foi mais bem sucedido na remoção do ruído das observações. O filtro de Kalman proporcionou resultados intuitivos que são interpretáveis mesmo para um público não técnico. Também se utilizaram dados de conversão para inferir estimativas semanais de alteração de competitividade. Propusemos modelos de regressão penalizada em que o tempo é incluído como uma estrutura de passeio aleatório. O modelo utiliza ponderadores de credibilidade para combinar alterações em cada segmento com as alterações da carteira. A estrutura hierárquica do modelo produz estimativas para as alterações de competitividade que são mais interpretáveis do que as dos modelos lineares generalizados, onde o tempo é incluído como uma variável categórica. Além disso, o método proposto supera os modelos lineares generalizados em termos de desempenho preditivo. Ambos os métodos podem servir como uma ferramenta para apoiar o processo de tomada de decisão sobre preços por parte das seguradoras, quando a disponibilidade de informação fiável sobre preços é limitada.
This work proposes several novel methods for inferring competitiveness of motor insurance policies in a setting of limited availability of price information. State-space functionalities are employed to filter noise from observations by introducing underlying time-dependent structures for transition and conversion data. Transition data of insurance companies of vehicles in the Portuguese insurance market was collected to analyze the evolution of the incoming transition probabilities of insurers. The binomial hidden Markov model is somewhat restricted due to its assumption of discrete state-space. The Kalman smoother is more successful in removing noise from the observations. The smoother provides intuitive results that are interpretable for a non-technical audience. Furthermore, conversion data was used to infer weekly segment-specific estimates of competitiveness changes. We have proposed a penalized regression framework where time is included as a random walk structure. The model uses credibility weighting on each segment's changes using the full portfolio's changes as the complement. The powerful hierarchical fashion of the model produces estimates of competitiveness changes that are more interpretable than those of generalized linear models, where time is included as a categorical variable. Moreover, the proposed method outperforms the generalized linear models in terms of predictive performance. Both methods can serve as a tool to support the price decision-making process by insurers when the availability of reliable price information is limited.
info:eu-repo/semantics/publishedVersion
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Ghassemi, Elham. "Modèle computationnel du contrôle auto-adaptatif cérébelleux basé sur la Logique Floue appliqué aux mouvements binoculaires : déficit de la coordination binoculaire de la saccade horizontale chez l’enfant dyslexique." Thesis, Paris 5, 2013. http://www.theses.fr/2013PA05L001.
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Ce travail de thèse porte essentiellement sur le cervelet. Nous y suivons deux axes majeurs : en termes de fonctions cérébelleuses, nous nous intéressons à l’apprentissage et l’adaptation du contrôle moteur ; en termes de dysfonctions cérébelleuses, nous nous intéressons à la dyslexie développementale.Nous nous orientons vers l’apprentissage du contrôle moteur afin d’en proposer un modèle computationnel fonctionnel appliqué aux mouvements oculaires volontaires. Pour ce faire, la Logique Floue est un de nos outils précieux. Nous avons proposé deux modèles. Le premier, AFCMAC (Auto-adaptive Fuzzy Cerebellar Model Articulation Controller), le résultat de l’intégration de la Logique Floue dans l’architecture de CMAC (Cerebellar Model Articulation Controller), est pourvu d’améliorer la vitesse/durée d’apprentissage et le besoin en termes de mémoire par rapport à CMAC. Le second modèle est CMORG (fuzzy logiC based Modeling for Oculomotor contRol LearninG), dont sa structure est également basée sur la Logique Floue, et dans lequel, le réseau de neurones est utilisé comme la mémoire pour gérer les règles Floues. Les résultats des évaluations des modèles proposés (AFCMAC et CMORG) et étudiés (CMAC et FCMAC – Fuzzy Cerebellar Model Articulation Controller), via les données oculomotrices des groupes d’enfants dyslexiques et contrôles lors de la lecture, montrent que CMORG est le plus performant à la fois, en termes de vitesse/durée d’apprentissage et également, de consommation de mémoire. Un autre avantage principal de CMORG par rapport aux autres modèles, est son interprétabilité par les experts.Concernant la dyslexie développementale, nous avons mené une étude expérimentale sur les déficits du contrôle moteur binoculaire lors des saccades des six enfants dyslexiques pendant les deux tâches différentes (la lecture d’un texte et la visualisation des chaînes de caractères) et dans les deux distances de vision (40 cm et 100 cm). Nous corroborons et adhérons à l’idée que la (mauvaise) qualité de la coordination binoculaire des saccades chez les enfants dyslexiques est indépendante des difficultés en lecture, associée peut-être aux hypothèses du déficit du magnosystème et du dysfonctionnement cérébelleuxThis thesis focuses on the cerebellum. We follow two main lines: in terms of cerebellar functions, we are interested in learning and adaptation motor control ; in terms of cerebellar dysfunctions, we are interested in developmental dyslexia.We focus on learning motor control in order to provide a functional computational model applied to voluntary eye movements. To this end, Fuzzy Logic is one of our valuable tools. We proposed two models. The former is AFCMAC (Auto-adaptive Fuzzy Cerebellar Model Articulation Controller), the result of the integration of Fuzzy Logic in CMAC (Cerebellar Model Articulation Controller) architecture, in order to improve learning speed/time and memory requirements compared to the CMAC. The latter is CMORG (fuzzy logiC based Modeling for Oculomotor contRol LearninG), whose structure is also based on Fuzzy Logic, and in which, the neural network is used as the memory to handle Fuzzy rules. The evaluation results of the proposed (AFCMAC and CMORG) and studied (CMAC and FCMAC – Fuzzy Cerebellar Model Articulation Controller) models via oculomotor data of dyslexic and control groups while reading show that CMORG is the most efficient both in terms of learning speed/time and also memory consumption. Another main advantage of CMORG over the other models is its interpretability by experts. Regarding the developmental dyslexia, we conducted an experimental study on binocular motor control deficits during saccades in six dyslexic children while two different tasks (text reading and character string scanning) and in two viewing distances (40 cm and 100 cm). We corroborate and adhere to the idea that the (bad) quality of binocular coordination of saccades in dyslexic children is independent of reading difficulties, maybe associated with magnosystem and cerebellar deficit hypothesis
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Davídek, Daniel. "Systém pro pokročilou vizuální teleprezenci." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221115.
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The introduction of this document presents some basic principles of visual telepresence with analysis of important aspects of the design. Afterwards there is a brief ovrewview of some of the applications of telepresence systems. Subsequently there is a description of the basic parameters and functions of the human visual perception system including the head motion parameters. This document examines the creation of telepresence apparatus through which is the user able to percieve visual stimuli accross distance. The device consist of camera with wide FOV positioned on the last link of the servo-motor chain with 3 DOF. Camera view is projected into scene in position read from actual motor posture. The scene is perceived through the HMD Oculus Rift (DK1, DK2) where the actual head-orientation read from the HMD inertial sensors is the entered end value for the rotation angles of the servomotors. A \csharp (WPF) program was developed for the controling and setting of motors which handles the byte communication through RS485-USB converter and also configures and starts the telepresence mode. The telepresence scene is drawn with help of SharpDX and SharpOVR - the \csharp wrappers of DirectX and LibOVR.
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Mathew, James. "Etude des mécanismes prédictifs sous-jacents à la coordination œil-main." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0329/document.
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La capacité de coordonner efficacement nos yeux avec nos mains est déterminante pour le succès de nos actions quotidiennes. En outre la capacité de prédire les conséquences sensorielles de nos propres actions est cruciale pour nos habilités motrices. Dans ce travail, à l’aide d’une tâche dans laquelle les participants doivent suivre avec leurs yeux une cible visuelle bougée par leur main, nous nous intéressons aux mécanismes prédictifs sous-tendant la coordination œil-main. Dans une première étude utilisant un protocole d’adaptation à une rotation visuomotrice, nous montrons que ces mécanismes prédictifs peuvent être mis à jour indépendamment de notre capacité à effectuer des mouvements précis de la main. Dans l’étude suivante nous cherchons à déterminer l’effet de la préférence manuelle, et montrons que malgré des différences évidentes en termes de précision concernant le contrôle manuel, la capacité d’anticiper les conséquences visuelles de nos actions reste identique que la cible soit bougée par la main droite ou gauche. Enfin, grâce à la stimulation magnétique transcranienne, nous testons l'hypothèse selon laquelle ces mécanismes prédictifs utilisent des signaux efférents de la main issus du cortex moteur primaire (M1). Nos résultats montrent que si cette contribution existe, elle doit se faire nécessairement en amont de M1. Au bout du compte nous proposons que la coordination œil-main soit sous-tendue par des mécanismes prédictifs similaires pour nos deux mains, situés vraisemblablement en amont de M1, et pouvant être mis à jour indépendamment du contrôle de la mainThe ability to coordinate efficiently eye and hand actions is central for humans in everyday activities. Furthermore it is argued that the ability to predict the sensory consequences of self-initiated movements is crucial for skilled motor behavior. Here by means of a task in which participants were asked to track with the eyes a visual target that was moved by their hand, we investigated the predictive mechanisms underlying eye-hand coordination. In a first study, using a protocol in which participants had to adapt to rotated hand visual feedback, we show that these predictive mechanisms can be updated independently of the ability to perform accurate hand movements. In a follow up study we tested the effect of hand dominance, and showed that, despite obvious differences in the accuracy of hand movement control, the ability to predict visual consequences of right and left hand actions was similar. Finally, by means of transcranial magnetic stimulation, we tested the hypothesis that those predictive mechanisms rely on hand efferent signals from the primary motor cortex (M1). However our results failed to support this view, and instead suggest that if such a contribution exists, it must be upstream of M1. Overall, we propose that eye-hand coordination relies on similar predictive mechanisms for both hands, possibly located upstream of M1, which can be updated independently of hand movement control
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Martínez-García, Marina. "Statistical analysis of neural correlates in decision-making." Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/283111.
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We investigated the neuronal processes which occur during a decision-
making task based on a perceptual classi cation judgment.
For this purpose we have analysed three di erent experimental paradigms
(somatosensory, visual, and auditory) in two di erent species (monkey and
rat), with the common goal of shedding light into the information carried by
neurons.
In particular, we focused on how the information content is preserved in
the underlying neuronal activity over time. Furthermore we considered how
the decision, the stimuli, and the con dence are encoded in memory and,
when the experimental paradigm allowed it, how the attention modulates
these features. Finally, we went one step further, and we investigated the
interactions between brain areas that arise during the process of decision-
making.Durant aquesta tesi hem investigat els processos neuronals que es pro- dueixen durant tasques de presa de decisions, tasques basades en un ju- dici l ogic de classi caci o perceptual. Per a aquest prop osit hem analitzat tres paradigmes experimentals diferents (somatosensorial, visual i auditiu) en dues espcies diferents (micos i rates), amb l'objectiu d'il.lustrar com les neurones codi quen informaci on referents a les t asques. En particular, ens hem centrat en com certes informacions estan cod- i cades en l'activitat neuronal al llarg del temps. Concretament, com la informaci o sobre: la decisi o comportamental, els factors externs, i la con- ana en la resposta, b e codi cada en la mem oria. A m es a m es, quan el paradigma experimental ens ho va permetre, com l'atenci o modula aquests aspectes. Finalment, hem anat un pas m es enll a, i hem analitzat la comu- nicaci o entre les diferents arees corticals, mentre els subjectes resolien una tasca de presa de decisions.
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Chung, Ji Yeon Jenni. "Consolidation of motor memory in the vestibulo-ocular reflex." 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=450638&T=F.
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Kißler, Johanna [Verfasser]. "Neuropsychological and ocular motor studies of schizophrenia / von Johanna Kißler." 2002. http://d-nb.info/964721031/34.
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Coelho, Joana Margarida Moreira da Rocha Rodrigues. "Ocular Motor and Vestibular Video-Oculographic Analysis in Parkinsonian Syndromes." Master's thesis, 2021. http://hdl.handle.net/10316/98467.
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Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de MedicinaAs Síndromes Parkinsonianas (PS) são doenças neurodegenerativas que refletem a função anormal da via cortico-basal. O comprometimento de diferentes partes do SNC leva a diferentes achados oculares em cada síndrome, tornando a análise dos movimentos oculares fulcral para o diagnóstico. No entanto, os movimentos oculares vestibulares nas PS têm sido menos estudados e há falta de análises de regressão multivariável para identificar alterações dos movimentos oculares preditoras da clínica entre os grupos. Neste trabalho, foi feita uma revisão retrospetiva dos movimentos oculares e dados vestibulares de doentes com PS (Doença de Parkinson [PD], Paralisia Supranuclear Progressiva [PSP], Atrofia de Sistemas Múltiplos [MSA] e Síndrome Cortico-basal [CBS]) que realizaram análise video-oculográfica detalhada e foi comparada entre grupos, correlacionando-a com os dados clínicos iniciais e um ano depois, e foram aplicadas análises de regressão multivariável para determinar o seu valor como preditor independente da progressão clínica. Encontrámos instabilidade da fixação do olhar significativa, sacadas lentas e hipométricas, e uma menor prevalência do nistagmo posicional na PSP, e diminuição do ganho na perseguição e sacadas com latência prolongada na CBS. O ganho na perseguição descendente foi um preditor independente da disfunção motora 1 ano depois da avaliação ocular entre grupos, e o ganho das sacadas verticais juntamente com a latência das sacadas horizontais e verticais constituíram um preditor significativo da dose de agonistas dopaminérgicos, tanto da dose inicial como da dose após um ano. A análise vestibular e dos movimentos oculares permitiu-nos distinguir os grupos PD, PSP, MSA e CBS. Adicionalmente, a perseguição vertical parece ser um preditor útil da progressão clínica das PS. A correlação potencial entre os agonistas dopaminérgicos e os movimentos oculares deve ser interpretada com cautela visto que podem simplesmente refletir a estratégia terapêutica de evitar o uso dos agonistas dopaminérgicos no parkinsonismo atípico. A avaliação detalhada dos movimentos oculares e vestibulares constitui uma ferramenta diagnóstica útil e um marcador da progressão clínica nas PS.
Parkinsonian Syndromes (PS) are neurodegenerative disorders that reflect abnormal function of basal ganglia–cortical circuits. Distinctive CNS impairment leads to specific ocular features in each syndrome, making eye movement analysis crucial for their diagnosis. However, vestibular eye movements have been less studied in PS and multivariate regression methods to find independent ocular motor predictors of clinical disability across groups are lacking.In this work, we retrospectively review ocular motor and vestibular data from PS patients (Parkinson’s disease [PD], Progressive Supranuclear Palsy [PSP], Multiple System Atrophy [MSA], and Cortico-Basal Syndrome [CBS]) who underwent detailed video-oculographic analysis and compared it between groups, correlated it with clinical data at baseline and 1-year after, and applied multivariate regression methods to ascertain their value as an independent predictor of clinical progression.We found significant ocular fixation instability, slow and hypometric saccades, and lower prevalence of positional nystagmus in PSP, and low gain pursuit and prolonged saccadic latency in CBS. Downward pursuit gain was an independent predictor of motor disability 1 year after ocular assessment across groups, and vertical saccade gain together with horizontal and vertical saccade latency constituted a significant predictor of dopaminergic agonists dosage at baseline and after 1 year.Ocular motor and vestibular analysis allowed us to clearly distinguish between PD, PSP, MSA and CBS groups. Additionally, vertical pursuit seems to be a helpful predictor of PS disability. Potential correlations between dopaminergic agonists and eye movement data should be cautiously interpreted since these might simply reflect overall clinician’s therapeutic strategy in avoiding the use of dopaminergic agonists in atypical parkinsonism. Detailed ocular motor assessment including ocular motor and vestibular data constitutes a powerful diagnostic tool and marker of clinical progression in PS.
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Titley, Heather. "Understanding the Mechanisms of Motor Learning in the Vestibulo-ocular Reflex." Thesis, 2011. http://hdl.handle.net/1807/31957.
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The vestibulo-ocular reflex (VOR) is a simple reflex that stabilizes gaze by moving the eyes in the opposite direction to the head. The gain of the VOR (ratio of head to eye velocity) can be increased or decreased during motor learning. It is thought that the memory for learned changes in the VOR gain is initially encoded within the cerebellar flocculus. Furthermore, these learned gain changes can be disrupted or consolidated into a long-term memory. In this thesis we describe novel results that show that consolidation of the VOR can take place rapidly, within 1 hour after learning has stopped. Furthermore, we demonstrated that unlike learning, which has been shown to have frequency selectivity, disruption and rapid consolidation generalize across the range of frequencies. We suggest that disruption and rapid consolidation in the VOR are local mechanisms within the cerebellar cortex, and do not require new learning. This thesis also provides additional evidence for the idea that learned gain increases and decreases are the result of separate mechanisms, most likely long-term depression and potentiation respectively, at the parallel fibre-Purkinje cell synapses. We demonstrate that learned gain increases, but not decreases, require the activation of type 1 metabotropic glutamate receptors (mGluR1) and B type γ-aminobutyric acid (GABAB) receptors. Blocking one or both of these receptors with an antagonist inverts gain-up learning, while the agonist augments gain-up learning. Furthermore, we provide novel evidence that these receptors are co-activated during gain-up learning.
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Carvalho, Mário César Teixeira Faria de. "Stroke and transient ischemic attack incidence after acute microvascular ocular motor palsies." Master's thesis, 2016. http://hdl.handle.net/10316/37052.
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Trabalho final do 6º ano médico com vista à atribuição do grau de mestre (área científica de neurologia) no âmbito do ciclo de estudos de Mestrado Integrado em Medicina.Background: In the past, microvascular ocular motor palsies (OMPs) have been regarded as a benign vascular condition with excellent prognosis. Purpose: To determine the incidence of subsequent stroke or transient ischemic attack (TIA) in acute isolated microvascular third, fourth and sixth cranial nerve palsies. Methods: The medical records of 95 consecutive patients presenting with ocular motor palsies (OMPs) in the Emergency Department of Coimbra University Hospital Center between January 2007 and October 2012 were reviewed. Results: Six out of 57 patients (10,5%) with presumed microvascular OMPs had subsequent stroke or TIA, 4 during the first year, 1 during the second year and 1 patient after this period. In comparison, only 1 out of 38 control subjects (2,5%) with non-microvascular OMPs developed subsequent stroke, albeit this difference has not reached statistical significance (P=0,149). Cumulative incidence of subsequent stroke or TIA was higher for the microvascular group, although not significantly (p=0,217). In the microvascular OMP group, age (p=0,633), gender (p=0,272), cranial nerve affected (p=0,256), the number of vascular risk factors (p=0,598), and the use of an antiplatelet agent before (p=0,313) or after the OMP (p=0,164), did not differed significantly between patients who had a subsequent stroke or TIA and those who did not. Conclusions: A significant proportion of patients with presumed microvascular OMPs developed subsequent stroke, approaching stroke recurrence rates previously reported for other stroke types (e.g., lacunar stroke). This finding emphasizes the importance of initiating a focused secondary prevention strategy when managing patients with presumed microvascular OMPs.
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Huang, Chi Ruei, and 黃祈瑞. "Reduction of ocular and motor interference in EEG by independent component analysis for event-related potential study." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/39865885585000841788.
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碩士長庚大學
電機工程學系
101
In this study, in order to reduce the interference of ocular and motor in EEG, we apply both independent component analysis and adaptive filter in event-related potential study. This way, in addition to test the feasibility of our proposed methods, we can also realize more about the function of brain areas, such as language and motor areas. Part One aims to investigate the relationship between pictures or words and ERPs, respectively. When the subjects see different visual stimuli, they must take some action (Naming). At this time, their EEG signals will be different. We hope that we could evaluate brain functioning(Semantic and Cognitive) in normal people by some specific EEG characteristics. More precisely, giving subjects visual (pictures or words) stimuli including three kinds of items, such as fruits, animals, and articles for daily use, we find that normal people’s ERPs can be separated and N170/N400 components can be easily identified. With the decrement of the ability to memorize and attention or something else, this situation will be much more unclear. Part Two is similar to Part One. But we ask subjects to take some real actions instead of naming when seeing visual stimuli, so that we can investigate the ERPs of real movement, too.
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Su, Yu Ren, and 蘇昱任. "Applying Independent Component Analysis to Remove Ocular and Motor Interference in EEG for Movement-Related Cortical Potentials." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/66654656822769250401.
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"Ocular changes in the black moor goldfish." 2000. http://library.cuhk.edu.hk/record=b6073300.
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Helen Wei Ling Lai."December 2000."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2000.
includes bibliographical references (p. 97-102).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.
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Catronas, Dinis Miguel Duarte. "The influence of sensorimotor training in learning a novel script: a comparison between handwriting and visual learning." Master's thesis, 2020. http://hdl.handle.net/10400.1/15119.
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Reading and writing are relatively recent cultural acquisitions in the history of human cognition, yet they have become essential to the functioning of today's modern society. It is well accepted that simple perceptive exposure to letters is not sufficient for the emergence of a highly specialized system in the brain to the ability to read and write an alphabet. Exactly what type of experiences are key for the emergence of the system devoted to letter processing is largely unknown. Recent research on this field has suggested that learning a new alphabet with motor integration (via handwriting) is more beneficial to visual letter recognition than other forms of practice such as mere visual exposure to the characters.
In the present study we wanted to explore whether and how visual-motor integration could be beneficial in learning a new alphabet compared to purely visual learning. For this aim, adult participants were exposed to a new alphabet, an artificial script, composed of 12 pseudoletters, each of them being associated with a corresponding syllabic sound. Thirty-six adults were trained in a novel set of letters, through either “visual-only” (mere visual exposure – Visual-Only Group) or “visual-to-motor” (visual exposure plus handwriting – Visual-Motor Group) practice over a three-days Learning Phase. Participants were asked to learn the new alphabet. Behavioral and eye-tracking tasks were created to evaluate the learning curve of the two experimental groups, the ability to recognize and discriminate the new letters after training, and their reading ability.
Significant differences between groups were found across Learning Phases; the Visual-Motor Group had higher Dwell Times. First Fixation Duration and Fixation Count on the last Learning Phase compared to the first Learning Phase than the Visual-Only group when correct responses were considered. These results seem to suggest that the group with the combined training spends more time on the correct response. On the other hand, the Visual-Motor Group spent less time and had lower fixation count on distractors compared to the Visual-Only Group, suggesting that the group with the combined training (visual and motor training) is sensitive to interference of an irrelevant target.A leitura e a escrita são invenções relativamente recentes na história da cognição humana, no entanto tornaram-se essenciais para o funcionamento da sociedade moderna atual. Apesar da aquisição da leitura e da escrita ser um fenómeno recente em termos evolutivos, o nosso cérebro reconhece letras em menos de 200ms. Esta rápida perceção do estímulo escrito deve-se à emergência de uma rede neuronal universal e altamente especializada para o reconhecimento de letras. É consensual na literatura que a simples exposição preceptiva às letras não é suficiente para o surgimento de um sistema altamente especializado no cérebro, capacitando-o para ler e escrever um alfabeto, sendo ainda amplamente desconhecido que tipo de experiências são essenciais para surgir no ser humano um sistema dedicado ao processamento de letras. Estudos recentes sobre esta temática sugerem que aprender um novo alfabeto com integração motora (escrita manual) é mais benéfico para o reconhecimento visual de letras do que outras formas de aprendizagem, como por exemplo, a mera exposição visual às letras. No presente estudo, pretendemos explorar se, e de que forma, a integração visuo-motora poderá ser benéfica na aprendizagem de um novo alfabeto quando comparada à aprendizagem puramente visual. Para isso, os participantes foram expostos a um novo alfabeto (script artificial), composto por 12 pseudoletras, cada um deles associado a um som silábico correspondente. Neste estudo participaram 36 sujeitos aleatoriamente divididos em dois grupos experimentais: o Grupo Visual, onde toda a aprendizagem realizada do novo alfabeto se desenrolou por estimulação puramente visual e auditiva; e o Grupo Visuo-Motor, onde além da exposição visual e auditiva era acrescentado um treino de componente motora. Todos os participantes foram submetidos a uma avaliação inicial de forma a garantir que não existiam diferenças ao nível da fluência leitora, idade de leitura e processamento específico de letras e pseudoletras. Esta avaliação permitiu, numa fase posterior, garantir que todas as diferenças entre sujeitos e grupos se deviam exclusivamente à manipulação experimental realizada e não a fatores que precedem ao estudo. Ao longo de três sessões de treino e avaliação, os participantes foram expostos ao novo alfabeto. Foram criadas tarefas comportamentais para avaliar a aprendizagem do novo alfabeto pelos dois grupos experimentais, não só no reconhecimento das novas letras, mas também na capacidade de leitura das mesmas. À exceção da forma como o alfabeto foi aprendido, ambos os grupos experimentais realizaram as mesmas tarefas. Para realizar a análise das mesmas optámos por utilizar medidas como Tempos de Resposta (ms) e Número de Acertos como diferenciadoras do nível de aprendizagem entre dias e entre grupos. Para além das tarefas comportamentais, utilizámos medidas fisiológicas, neste caso, medidas oculares (Eye-Tracking), para monitorizar o processo de aprendizagem dos participantes. Sendo uma janela de aprendizagem curta, as medidas oculares permitirão uma discriminação mais fina na avaliação dos benefícios de cada treino. Para isso foi construída uma tarefa de escolha múltipla onde após a apresentação do som correspondente a uma das novas letras aprendidas, o participante tinha de escolher uma das quatro opções de resposta enquanto os seus movimentos oculares eram monitorizados. As quatro opções eram compostas por: uma resposta correta; um distrator visual (rotação no plano de 90 ou 180 graus da opção correta); um distrator fonológico (uma letra aprendida que fosse fonologicamente similar à resposta correta) e por um distrator puro (uma letra aprendida que não se assemelhava visualmente ou fonologicamente à resposta correta). Na análise dos dados extraídos desta prova, focámo-nos em três medidas oculares: Duração da primeira fixação (ms), Tempo Total da Fixação (ms) e Número Total de Fixações. Foram encontradas diferenças significativas entre grupos que tendem a apoiar a nossa hipótese inicial: o grupo que realiza a aprendizagem com integração motora (Grupo Visuo-Motor) revela uma aprendizagem mais eficaz, demonstrando melhores capacidades de leitura e discriminação das novas letras aprendidas quando comparado com o Grupo Visual. Estas diferenças revelaram-se particularmente significativas na análise das medidas oculares ao longo das sessões de aprendizagem, onde o Grupo Visuo-Motor apresentou valores mais elevados de Tempo Total de Fixação e de Duração da Primeira Fixação para a resposta correta. Estes resultados levam-nos a concluir que o Grupo Visuo-Motor não só despende mais tempo e atenção no alvo (resposta correta) do que nos distratores adjacentes, como também desenvolve resistência a esses mesmos distratores, quando comparado com o Grupo Visual.
Gostaria de agradecer à FCT (Fundação para a Ciência e Tecnologia) e à FEDER (Fundo Europeu de Desenvolvimento Regional) pelo financiamento através do projeto: project VOrtEx (ref PTDC/PSI-GER/28184/2017) funded by Fundação para a Ciência e Tecnologia, FCT, and by FEDER (POR Lisboa 2020)