Of all motor skills, manual reaching might be the one ability that matters most for infants’ perceptual, cognitive and social development. Reaching allows infants to learn about object properties, but also gives opportunities for socializing with others. The general aim of the present thesis was to study the importance of manual motor development in infancy from different perspectives; first, through examining stereopsis as a prerequisite for efficient reaching development, second, with regard to understanding others goal-directed reach actions by means of the mirror neuron system (MNS), and third, in relation to possible atypical development, with a specific focus on autism spectrum disorder (ASD). Study I shows that under monocular viewing conditions, infants at six, eight and 10 months of age perform slower and less accurate reaches. Longer times to object contact during monocular trials specifically imply that motor prediction is less effective when depth and distance information is compromised. Study II demonstrates that, by eight months of age, infants seem to have a MNS that functions in a similar manner to the adult MNS, thus activity can be registered over the motor cortex when infants simply observe an action they can master themselves. This activation is predictive, indicating anticipation of the goal of the observed reach. Study III indicates that infants at elevated familial risk for ASD present with reduced prospective motor control at 10 months of age. Compared to a low-risk control sample, high-risk infants perform reactive rather than predictive reach actions. Follow-up assessment at 36 months will show whether this measure can be used as a predictive diagnostic marker for ASD. The main contribution given by this work is the insight that it is important to take manual motor aspects into account when considering typical as well as atypical cognitive and social development, and in addition, that motor prediction is a key factor behind being able to timely execute and understand reaching actions.

Made available in DSpace on 2016-06-02T20:13:10Z (GMT). No. of bitstreams: 1 2606.pdf: 930592 bytes, checksum: f4756c2d671b859733477486438959b2 (MD5) Previous issue date: 2009-03-06 / The research is an investigation about the phenomenon of the Laugh, from the studies of Henri Bergson and Sigmund Freud up to today's research on neuroscience, gelotology and several other studies on human behaviour. In order to better understand the Laugh, an accurate evaluation of the book " Laughter: An Essay on the Meaning of the Comic", by Henri Bergson is made as an attempt to better understand the main considerations set by the author, in his interpretation of this phenomenon as a Social Gesture and all the implications originated by such fact. In the second chapter of this study, Jokes and their Relation to the Unconscious , by Sigmund Freud, are closely analyzed in details, comparing Freud s and Bergson s approaches and analyzing the mechanisms proposed by Freud concerning the way the Joke works, pointing out the reasons why they would be told to others. The reading and analysis of this book are directed specifically to the study of the Laugh, not approaching any other aspect, relevant to the reading of Freud s work as a whole, which however, would deviate the focus of this work. All the efforts were dedicated to the comprehension of the jokes mechanisms studied by Freud as well as ways to obtain pleasure through them. At the end updated research is verified, such as the one from Richard Wiseman s Laugh Laboratory, that accomplished a worldwide research selecting which would be considered the funniest jokes by people. Also as an object of study there is the role of the mirror-neurones, an important finding that allows a clearer vision about primates and human s social behaviors. The possibility of the laughter to be a behaviour similar to the grooming of the primates is also raised, since both would be related to the exchange of pleasure among individuals viewing the benefit of the group. Following this line, a study is presented defining the laughter as a specific characteristic of the male gender, who would use this feature as an approach aiming at attracting a mate. There isn't a conclusive result, there is not a final word about the laughter because it is clear that in many circumstances the term ranges similar phenomena, which are not exactly the same. In the same way that there is multiple laughter, there are multiple areas that study the distinct variations of the Laugh. / A pesquisa é uma investigação sobre o fenômeno do Riso, partindo dos estudos de Henri Bergson e Sigmund Freud até as pesquisas atuais da neurociência, da gelotologia e dos variados estudos sobre o comportamento humano. Para compreender melhor o Riso, é feita uma avaliação detalhada do livro O Riso , de Henri Bergson, buscando compreender as considerações fundamentais estabelecidas pelo autor, na sua interpretação deste fenômeno como um Gesto Social e todas as implicações que derivam deste fato. No segundo capítulo deste estudo é analisado com detalhes O Chiste e sua relação com o Inconsciente , de Sigmund Freud, comparando as abordagens de Freud e Bergson e analisando os mecanismos propostos por Freud para o funcionamento do chiste e quais as razões pelas quais eles seriam contados. A leitura e análise deste livro são dirigidas especificamente ao estudo do Riso, deixando de abordar outros aspectos, importantes para a leitura da obra de Freud como um todo, mas que desviariam o foco deste trabalho. Todo o esforço foi dedicado à compreensão dos mecanismos do chiste estudados por Freud e das formas de obtenção de prazer através deles. Ao final, pesquisas atuais são estudadas, como as do Laboratório do Riso de Richard Wiseman, que realizou uma pesquisa mundial sobre quais seriam as piadas consideradas mais engraçadas pelas pessoas. Investiga-se também o papel dos neurônios-espelho, importante descoberta que permite uma visão mais clara sobre comportamentos sociais de humanos e primatas. A possibilidade de o riso ser um comportamento semelhante ao grooming dos primatas também é levantada, já que ambas seriam trocas de prazer entre indivíduos visando um benefício dentro do grupo. Nesta linha, é apresentado um estudo que define o riso como uma característica específica do gênero masculino, que usaria o recurso para aproximação da fêmea visando acasalamento. Não há um resultado conclusivo, não há uma palavra final sobre o Riso, pois se torna claro que em muitas circunstâncias o termo abarca fenômenos semelhantes, mas não exatamente iguais. Da mesma maneira que existem múltiplos risos, também existem múltiplas áreas que estudam as distintas variações do Riso.

Made available in DSpace on 2016-03-15T19:39:55Z (GMT). No. of bitstreams: 1 Olivia Morgan Lapenta.pdf: 1151745 bytes, checksum: 91e51a2bad20664489c6aae6c59924b6 (MD5) Previous issue date: 2012-08-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Mental Simulation theory suggests activation of the motor network during imagery and execution of movements, similarly to the activation during observation and execution of actions, which is mediated by the Mirror Neuron System. This activation can be measured using eletroencefalography register of Mu rhythm suppression. It is propose that motor network activation and therefore increase of cortical excitability at primary motor cortex and Mu dessynchronization are due to premotor Miror-Neuron System inputs. Transcranial direct current stimulation is a neuromodulation technique that induce facilitation and inhibition of neural firing leading to enhance or decrease in cortical excitability, respectively. Thus, we propose to evaluate the polarity dependent effects of this technique in the Mu rhythm during biological and non-biological movements observation and imagery tasks. Therefore we applied anodal, cathodal and sham stimulation in 21 male subjects (mean age 23.8+3,06), over left primary motor cortex (2mA for 20min) and immediately after we registered the electroencephalography considering the electrodes C3, C4 and surrounding C3 and C4 and Cz. Analyses of C3 and C4 showed significant effects according to Movement (p=0.005), and also for the interactions between type of stimulation and hemisphere (p=0.04) and type of stimulation, movement and hemisphere (p=0.02). Surrounding electrodes analyses revealed significant effect for the interaction between stimulation type, task condition and movement type (p=0.03). Thus, the main findings of this study were i. Mu suppression for biological movement (in both imagery and observation) of the hand region in the contralateral hemisphere after sham stimulation, ii. reverse effect for the surrounding electrodes during imagery condition and iii. polarity-dependent neuromodulation of the Mu rhythm. The results are discussed considering focal ERD/ surrounding ERS according to the type of task. We concluded that there are contralateral focal Mu dessynchronization during observation and imagery of biological movements together with syncronizarion of the motor areas not involved in the task only for the imagery condition and that transcranial direct current stimulation has a significant effect under the entire electrode and according to the applied polarity. The use of transcranial direct current stimulation followed by observation and imagery tasks might be an interesting intervention strategy for disturbances involving motor ability impairment as well as deficits related to imitation and comprehension of other s actions. / A teoria de simulação mental sugere ativação da rede neural motora durante mentalização e execução de movimentos, de maneira análoga à ativação em observação e execução de ações, o que é mediado pelo Sistema de Neurônios-Espelho. Esta ativação pode ser mensurada por supressão do ritmo Mu registrado por eletroencefalografia. É proposto que a ativação de áreas motoras e, portanto, o aumento de excitabilidade cortical em cortex motor primário e a dessincronização do ritmo Mu ocorram em consequência de insumo proveniente do Sistema Neurônios-Espelho pré-motor. A estimulação transcraniana por corrente contínua consiste numa técnica de neuromodulação por facilitação e inibição de disparo neuronal levando a aumento e redução de excitabilidade cortical, respectivamente. Assim, foi proposto avaliar os efeitos polaridade dependentes desta técnica sobre ritmo Mu durante tarefas de observação e mentalização de movimentos biológicos e não biológicos. Para tal, aplicamos estimulação anódica, catódica e placebo em 21 homens destros (idade média de 23.8+3,06), sobre córtex motor primário esquerdo (2mA por 20min) e, em seguida foi feito o registro eletroencefalográfico considerando os eletrodos C3, C4 e entorno de C3 e C4 e Cz. A análise de C3 e C4 apresentou efeitos significativos quanto ao tipo de Movimento (p=0.005) e ainda quanto as interações entre tipo de estimulação e hemisfério (p=0.04) e tipo de estimulação, de movimento e hemisfério (p=0.02). A análise dos eletrodos do entorno revelou efeito significativo para a interação entre tipo de estimulação, condição da tarefa e tipo de movimento (p=0.03). Assim, os principais achados do estudo foram i. supressão de Mu para movimento biológico (em mentalização e observação) da região da mão em hemisfério contralateral após estimulação placebo, ii. efeitos inversos para eletrodos de entorno em condição de mentalização e iii. neuromodulação polaridade dependente de ritmo Mu. Os resultados de oscilação de Mu são discutidos considerando ERD focal/ ERS entorno de acordo com o tipo de tarefa. Concluímos que há dessincronização contralateral focal de Mu durante observação e mentalização de movimentos biológicos, acompanhada por sincronização de áreas motoras não envolvidas na tarefa apenas na condição de mentalização e que a estimulação transcraniana por corrente contínua tem efeito sob toda a superfície do eletrodo e difere de acordo com a polaridade aplicada. O uso da estimulação transcraniana por corrente contínua combinada com tarefas de observação e mentalização pode conferir uma estratégia interessante de intervenção em distúrbios envolvendo comprometimento das habilidades motoras bem como comprometimento de habilidades de imitação e compreensão das ações do outro.

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Denna uppsatsen undersöker varför våld i film är så utbrett och populärt. Jag använder mig av ett evolutionärbiologiskt perspektiv, som tidigare inte använts vid filmforskning i så stor utsträckning. Istället har filmforskning och andra studier på människans beteende oftast utgått ifrån ett socialkonstruktivistiskt perspektiv. Uppsatsen är av typen ”forskningsöversikt” vilket innebär att jag inte har gjort någon klassisk analys på ett filmiskt verk eller empiriskt material, utan har sammanställt en stor mängd forskning från andra forskare. För att kunna svara på min frågeställning har jag behövt forska inom mänsklig evolution, audiovisuell perception samt våld i film. Den viktigaste bokenför uppsatsen kom att bli Torben Grodals Embodied Visions. Huvudfrågan i min frågeställning löd: Vilka faktorer ligger enligt tidigare forskning bakom populariteten av våldsskildringar?Svar: 1. Film är utformad för att påverka oss, aktivera känslor. 2. Det som påverkar ossallra mest är de bilder som påminner om de djupast rotade mekanismerna inuti oss. 3. Av evolutionära skäl ingår våld och aggressivitet bland dessa djupt rotade mekanismer. / This paper examines why violence in films is so widespread and popular. I use an evolutionary biological perspective, that has not previously been used in film research as much. Instead, the film research and other studies on human behavior usually originate from a social constructionist perspective. The essay is a "research review", which means that I have not made a classic analysis of a cinematic work or empirical data, but have collected a large amount of research from other scientists. To be able to answer my question, I had to do research in human evolution, audio visual perception and violence in film. The most important book for the essay came to be Torben Grodals Embodied Visions. The main question in my research question was: What factors are in accordance with previous research behind the popularity of graphic violence? Answer: 1. Film is designed to affect us, activating emotions. 2. what affects us the most is images that reminds us of deeply rooted mechanisms inside us. 3. of evolutionary reasons, violence and aggression are among these deep-rooted mechanisms.

L'obiettivo principale del lavoro è stato di valutare il ruolo della neurostimolazione e della multimodalità (intesa come la presentazione visiva di un modello che esegue un movimento assieme a una musica sincrona) nell’apprendimento motorio, indagando sia gli effetti sugli adulti sani sia su pazienti affetti da Morbo di Parkinson (MP). Per raggiungere tale obiettivo, sono state condotte tre ricerche sperimentali e longitudinali, utilizzando diversi strumenti, come tDCS, biofeedback e KinectTM. Partendo da una sistematica revisione della letteratura nel campo della riabilitazione neuromotoria, sono state identificate tre forme di trattamento che sembrano efficaci contro i sintomi motori del MP. Tuttavia, pur riconoscendo la loro efficacia, non sono mai stati combinati nella pratica riabilitativa: l’Action Observation Learning (basato sulla teoria del sistema dei neuroni specchio), la neurostimolazione anodica non-invasiva sulla zona motoria primaria e l'uso della musica. I risultati dimostrano un chiaro sostegno della multimodalità e della neuro stimolazione nella fase di encoding e un loro supporto nel migliorare le funzioni motorie, anche a distanza di un mese. Questo lavoro offre nuove indicazioni per lo sviluppo di approcci innovativi ed efficaci nel campo dell’apprendimento motorio. / The main objective was to assess the role of neurostimulation and multimodality (namely the presentation of a visual model together with a synchronized musical track) in motor learning, by considering both healthy adults and Parkinsonian patients (PD). In order to achieve this goal, three experimental and longitudinal studies were carried out, using different tools such as tDCS, biofeedback and KinectTM. Starting with a systematic review, three innovative approaches which seem to be effective in treating the motor symptoms of PD, were identified. However, while recognizing the effectiveness of these three promising approaches, they have never been combined: Action Observation Learning (based on the theory of mirror neuron system), the non-invasive anodal neurostimulation on the primary motor area and the use of music. The results showed a clear support of multimodality and neurostimulation during the encoding phase and in improving motor functions, even after one month. This work provides new suggestions for innovative and effective treatments in motor learning field.

Brain-computer interfaces (BCI) have been used to control the gait of a virtual self-avatar with the aim of being used in gait rehabilitation. A BCI decodes the brain signals representing a desire to do something and transforms them into a control command for controlling external devices. The feelings described by the participants when they control a self-avatar in an immersive virtual environment (VE) demonstrate that humans can be embodied in the surrogate body of an avatar (ownership illusion). It has recently been shown that inducing the ownership illusion and then manipulating the movements of one’s self-avatar can lead to compensatory motor control strategies. In order to maximize this effect, there is a need for a method that measures and monitors embodiment levels of participants immersed in virtual reality (VR) to induce and maintain a strong ownership illusion. This is particularly true given that reaching a high level of both BCI performance and embodiment are inter-connected. To reach one of them, the second must be reached as well. Some limitations of many existing systems hinder their adoption for neurorehabilitation: 1- some use motor imagery (MI) of movements other than gait; 2- most systems allow the user to take single steps or to walk but do not allow both, which prevents users from progressing from steps to gait; 3- most of them function in a single BCI mode (cue-paced or self-paced), which prevents users from progressing from machine-dependent to machine-independent walking. Overcoming the aforementioned limitations can be done by combining different control modes and options in one single system. However, this would have a negative impact on BCI performance, therefore diminishing its usefulness as a potential rehabilitation tool. In this case, there will be a need to enhance BCI performance. For such purpose, many techniques have been used in the literature, such as providing modified feedback (whereby the presented feedback is not consistent with the user’s MI), sequential training (recalibrating the classifier as more data becomes available). This thesis was developed over 3 studies. The objective in study 1 was to investigate the possibility of measuring the level of embodiment of an immersive self-avatar, during the performing, observing and imagining of gait, using electroencephalogram (EEG) techniques, by presenting visual feedback that conflicts with the desired movement of embodied participants. The objective of study 2 was to develop and validate a BCI to control single steps and forward walking of an immersive virtual reality (VR) self-avatar, using mental imagery of these actions, in cue-paced and self-paced modes. Different performance enhancement strategies were implemented to increase BCI performance. The data of these two studies were then used in study 3 to construct a generic classifier that could eliminate offline calibration for future users and shorten training time. Twenty different healthy participants took part in studies 1 and 2. In study 1, participants wore an EEG cap and motion capture markers, with an avatar displayed in a head-mounted display (HMD) from a first-person perspective (1PP). They were cued to either perform, watch or imagine a single step forward or to initiate walking on a treadmill. For some of the trials, the avatar took a step with the contralateral limb or stopped walking before the participant stopped (modified feedback). In study 2, participants completed a 4-day sequential training to control the gait of an avatar in both BCI modes. In cue-paced mode, they were cued to imagine a single step forward, using their right or left foot, or to walk forward. In the self-paced mode, they were instructed to reach a target using the MI of multiple steps (switch control mode) or maintaining the MI of forward walking (continuous control mode). The avatar moved as a response to two calibrated regularized linear discriminant analysis (RLDA) classifiers that used the μ power spectral density (PSD) over the foot area of the motor cortex as features. The classifiers were retrained after every session. During the training, and for some of the trials, positive modified feedback was presented to half of the participants, where the avatar moved correctly regardless of the participant’s real performance. In both studies, the participants’ subjective experience was analyzed using a questionnaire. Results of study 1 show that subjective levels of embodiment correlate strongly with the power differences of the event-related synchronization (ERS) within the μ frequency band, and over the motor and pre-motor cortices between the modified and regular feedback trials. Results of study 2 show that all participants were able to operate the cued-paced BCI and the selfpaced BCI in both modes. For the cue-paced BCI, the average offline performance (classification rate) on day 1 was 67±6.1% and 86±6.1% on day 3, showing that the recalibration of the classifiers enhanced the offline performance of the BCI (p < 0.01). The average online performance was 85.9±8.4% for the modified feedback group (77-97%) versus 75% for the non-modified feedback group. For self-paced BCI, the average performance was 83% at switch control and 92% at continuous control mode, with a maximum of 12 seconds of control. Modified feedback enhanced BCI performances (p =0.001). Finally, results of study 3 show that the constructed generic models performed as well as models obtained from participant-specific offline data. The results show that there it is possible to design a participant-independent zero-training BCI. / Les interfaces cerveau-ordinateur (ICO) ont été utilisées pour contrôler la marche d'un égo-avatar virtuel dans le but d'être utilisées dans la réadaptation de la marche. Une ICO décode les signaux du cerveau représentant un désir de faire produire un mouvement et les transforme en une commande de contrôle pour contrôler des appareils externes. Les sentiments décrits par les participants lorsqu'ils contrôlent un égo-avatar dans un environnement virtuel immersif démontrent que les humains peuvent être incarnés dans un corps d'un avatar (illusion de propriété). Il a été récemment démontré que provoquer l’illusion de propriété puis manipuler les mouvements de l’égo-avatar peut conduire à des stratégies de contrôle moteur compensatoire. Afin de maximiser cet effet, il existe un besoin d'une méthode qui mesure et surveille les niveaux d’incarnation des participants immergés dans la réalité virtuelle (RV) pour induire et maintenir une forte illusion de propriété. D'autre part, atteindre un niveau élevé de performances (taux de classification) ICO et d’incarnation est interconnecté. Pour atteindre l'un d'eux, le second doit également être atteint. Certaines limitations de plusieurs de ces systèmes entravent leur adoption pour la neuroréhabilitation: 1- certains utilisent l'imagerie motrice (IM) des mouvements autres que la marche; 2- la plupart des systèmes permettent à l'utilisateur de faire des pas simples ou de marcher mais pas les deux, ce qui ne permet pas à un utilisateur de passer des pas à la marche; 3- la plupart fonctionnent en un seul mode d’ICO, rythmé (cue-paced) ou auto-rythmé (self-paced). Surmonter les limitations susmentionnées peut être fait en combinant différents modes et options de commande dans un seul système. Cependant, cela aurait un impact négatif sur les performances de l’ICO, diminuant ainsi son utilité en tant qu'outil potentiel de réhabilitation. Dans ce cas, il sera nécessaire d'améliorer les performances des ICO. À cette fin, de nombreuses techniques ont été utilisées dans la littérature, telles que la rétroaction modifiée, le recalibrage du classificateur et l'utilisation d'un classificateur générique. Le projet de cette thèse a été réalisé en 3 études, avec objectif d'étudier dans l'étude 1, la possibilité de mesurer le niveau d'incarnation d'un égo-avatar immersif, lors de l'exécution, de l'observation et de l'imagination de la marche, à l'aide des techniques encéphalogramme (EEG), en présentant une rétroaction visuelle qui entre en conflit avec la commande du contrôle moteur des sujets incarnés. L'objectif de l'étude 2 était de développer un BCI pour contrôler les pas et la marche vers l’avant d'un égo-avatar dans la réalité virtuelle immersive, en utilisant l'imagerie motrice de ces actions, dans des modes rythmés et auto-rythmés. Différentes stratégies d'amélioration des performances ont été mises en œuvre pour augmenter la performance (taux de classification) de l’ICO. Les données de ces deux études ont ensuite été utilisées dans l'étude 3 pour construire des classificateurs génériques qui pourraient éliminer la calibration hors ligne pour les futurs utilisateurs et raccourcir le temps de formation. Vingt participants sains différents ont participé aux études 1 et 2. Dans l'étude 1, les participants portaient un casque EEG et des marqueurs de capture de mouvement, avec un avatar affiché dans un casque de RV du point de vue de la première personne (1PP). Ils ont été invités à performer, à regarder ou à imaginer un seul pas en avant ou la marche vers l’avant (pour quelques secondes) sur le tapis roulant. Pour certains essais, l'avatar a fait un pas avec le membre controlatéral ou a arrêté de marcher avant que le participant ne s'arrête (rétroaction modifiée). Dans l'étude 2, les participants ont participé à un entrainement séquentiel de 4 jours pour contrôler la marche d'un avatar dans les deux modes de l’ICO. En mode rythmé, ils ont imaginé un seul pas en avant, en utilisant leur pied droit ou gauche, ou la marche vers l’avant . En mode auto-rythmé, il leur a été demandé d'atteindre une cible en utilisant l'imagerie motrice (IM) de plusieurs pas (mode de contrôle intermittent) ou en maintenir l'IM de marche vers l’avant (mode de contrôle continu). L'avatar s'est déplacé en réponse à deux classificateurs ‘Regularized Linear Discriminant Analysis’ (RLDA) calibrés qui utilisaient comme caractéristiques la densité spectrale de puissance (Power Spectral Density; PSD) des bandes de fréquences µ (8-12 Hz) sur la zone du pied du cortex moteur. Les classificateurs ont été recalibrés après chaque session. Au cours de l’entrainement et pour certains des essais, une rétroaction modifiée positive a été présentée à la moitié des participants, où l'avatar s'est déplacé correctement quelle que soit la performance réelle du participant. Dans les deux études, l'expérience subjective des participants a été analysée à l'aide d'un questionnaire. Les résultats de l'étude 1 montrent que les niveaux subjectifs d’incarnation sont fortement corrélés à la différence de la puissance de la synchronisation liée à l’événement (Event-Related Synchronization; ERS) sur la bande de fréquence μ et sur le cortex moteur et prémoteur entre les essais de rétroaction modifiés et réguliers. L'étude 2 a montré que tous les participants étaient capables d’utiliser le BCI rythmé et auto-rythmé dans les deux modes. Pour le BCI rythmé, la performance hors ligne moyenne au jour 1 était de 67±6,1% et 86±6,1% au jour 3, ce qui montre que le recalibrage des classificateurs a amélioré la performance hors ligne du BCI (p <0,01). La performance en ligne moyenne était de 85,9±8,4% pour le groupe de rétroaction modifié (77-97%) contre 75% pour le groupe de rétroaction non modifié. Pour le BCI auto-rythmé, la performance moyenne était de 83% en commande de commutateur et de 92% en mode de commande continue, avec un maximum de 12 secondes de commande. Les performances de l’ICO ont été améliorées par la rétroaction modifiée (p = 0,001). Enfin, les résultats de l'étude 3 montrent que pour la classification des initialisations des pas et de la marche, il a été possible de construire des modèles génériques à partir de données hors ligne spécifiques aux participants. Les résultats montrent la possibilité de concevoir une ICO ne nécessitant aucun entraînement spécifique au participant.