The Impact of Being Born with Cleft and Cleft Reparative Surgery on Overall Health and Speech Outcomes

Orofacial cleft is one of the most common and treatable birth defects in the world. If left untreated, orofacial cleft can impair normal speech development, growth, and could lead to a number of health consequences later in life. The main motivation of the study is to measure the impact of being born with cleft and the cleft reparative surgery on overall speech and health cleft for teenagers in India using difference-in-differences approach along with household fixed effects method. An overall health outcome was measured using height, weight, grip strength and BMI, and the speech acceptability was measured using a “Universal Parameters of Speech Evaluation”. At the current sample size, the result suggests that there is no significant impact of being born with cleft and receiving cleft reparative surgery on the overall health outcome. However, being born with cleft decreases overall speech acceptability by 0.327 (

EEG Signal Processing in Motor Imagery Brain Computer Interfaces with Improved Covariance Estimators

Desde hace unos años hasta la actualidad, el desarrollo en el campo de los interfaces cerebro ordenador ha ido aumentando. Este aumento viene motivado por una serie de factores distintos. A medida que aumenta el conocimiento acerca del cerebro humano y como funciona (del que aún se conoce relativamente poco), van surgiendo nuevos avances en los sistemas BCI que, a su vez, sirven de motivación para que se investigue más acerca de este órgano. Además, los sistemas BCI abren una puerta para que cualquier persona pueda interactuar con su entorno independientemente de la discapacidad física que pueda tener, simplemente haciendo uso de sus pensamientos. Recientemente, la industria tecnológica ha comenzado a mostrar su interés por estos sistemas, motivados tanto por los avances con respecto a lo que conocemos del cerebro y como funciona, como por el uso constante que hacemos de la tecnología en la actuali- dad, ya sea a través de nuestros smartphones, tablets u ordenadores, entre otros muchos dispositivos. Esto motiva que compañías como Facebook inviertan en el desarrollo de sistemas BCI para que tanto personas sin discapacidad como aquellas que, si las tienen, puedan comunicarse con los móviles usando solo el cerebro. El trabajo desarrollado en esta tesis se centra en los sistemas BCI basados en movimien- tos imaginarios. Esto significa que el usuario piensa en movimientos motores que son interpretados por un ordenador como comandos. Las señales cerebrales necesarias para traducir posteriormente a comandos se obtienen mediante un equipo de EEG que se coloca sobre el cuero cabelludo y que mide la actividad electromagnética producida por el cere- bro. Trabajar con estas señales resulta complejo ya que son no estacionarias y, además, suelen estar muy contaminadas por ruido o artefactos. Hemos abordado esta temática desde el punto de vista del procesado estadístico de la señal y mediante algoritmos de aprendizaje máquina. Para ello se ha descompuesto el sistema BCI en tres bloques: preprocesado de la señal, extracción de características y clasificación. Tras revisar el estado del arte de estos bloques, se ha resumido y adjun- tado un conjunto de publicaciones que hemos realizado durante los últimos años, y en las cuales podemos encontrar las diferentes aportaciones que, desde nuestro punto de vista, mejoran cada uno de los bloques anteriormente mencionados. De manera muy resumida, para el bloque de preprocesado proponemos un método mediante el cual conseguimos nor- malizar las fuentes de las señales de EEG. Al igualar las fuentes efectivas conseguimos mejorar la estima de las matrices de covarianza. Con respecto al bloque de extracción de características, hemos conseguido extender el algoritmo CSP a casos no supervisados. Por último, en el bloque de clasificación también hemos conseguido realizar una sepa- ración de clases de manera no supervisada y, por otro lado, hemos observado una mejora cuando se regulariza el algoritmo LDA mediante un método específico para Gaussianas.The research and development in the field of Brain Computer Interfaces (BCI) has been growing during the last years, motivated by several factors. As the knowledge about how the human brain is and works (of which we still know very little) grows, new advances in BCI systems are emerging that, in turn, serve as motivation to do more re- search about this organ. In addition, BCI systems open a door for anyone to interact with their environment regardless of the physical disabilities they may have, by simply using their thoughts. Recently, the technology industry has begun to show its interest in these systems, mo- tivated both by the advances about what we know of the brain and how it works, and by the constant use we make of technology nowadays, whether it is by using our smart- phones, tablets or computers, among many other devices. This motivates companies like Facebook to invest in the development of BCI systems so that people (with or without disabilities) can communicate with their devices using only their brain. The work developed in this thesis focuses on BCI systems based on motor imagery movements. This means that the user thinks of certain motor movements that are in- terpreted by a computer as commands. The brain signals that we need to translate to commands are obtained by an EEG device that is placed on the scalp and measures the electromagnetic activity produced by the brain. Working with these signals is complex since they are non-stationary and, in addition, they are usually heavily contaminated by noise or artifacts. We have approached this subject from the point of view of statistical signal processing and through machine learning algorithms. For this, the BCI system has been split into three blocks: preprocessing, feature extraction and classification. After reviewing the state of the art of these blocks, a set of publications that we have made in recent years has been summarized and attached. In these publications we can find the different contribu- tions that, from our point of view, improve each one of the blocks previously mentioned. As a brief summary, for the preprocessing block we propose a method that lets us nor- malize the sources of the EEG signals. By equalizing the effective sources, we are able to improve the estimation of the covariance matrices. For the feature extraction block, we have managed to extend the CSP algorithm for unsupervised cases. Finally, in the classification block we have also managed to perform a separation of classes in an blind way and we have also observed an improvement when the LDA algorithm is regularized by a specific method for Gaussian distributions

Intersubjectivity, Empathy and Nonverbal Interaction

PhDEmpathy is thought to involve cognitive processes that depend on the simulation of another's experiences. Embodiment has a key role for empathy as vehicle for recreating the experience of another. This thesis explores the validity of this claim by investigating what people do when communicating about their experiences. In particular, what is the contribution of our embodied resources such as gestures, postures and expressions to empathy and intersubjectivity? These questions are explored against two corpora of dyadic interactions. One features conversations of people describing recalled embodied experiences to each other, such as painful or pleasant bodily experiences like a headache or laughing. The other features a series of interactions designed to emulate informal conversations. The analysis uses hand coded gestures, feedback and clari cation questions, body movement data and a new approach to quantifying posture congruence. The analysis shows the embodied responses observed within these interactions are intentionally placed and formulated to facilitate the incremental process of a conversation as a joint activity. This is inconsistent with accounts that propose there is an automatic and non-conscious propensity for people to mimic each other in social interactions. Quantitative analysis show that patterns of gesture type and use, feedback form and posture di er systematically between interlocutors. Additionally, results show that resources provided by embodiment are allocated strategically. Nonverbal contributions increase in frequency and adjust their form responding to problems in conversation such as during clari cation questions and repair. Detailed qualitative analysis shows the instances that appear to display mimicry within the interaction function rather as embodied adaptations or paraphrases. In their contrast with the original contribution they demonstrate a speci c understanding of the type of experience being conveyed. This work shows that embodiment is an important resource for intersubjectivity and embodied communication is speci cally constructed to aid the collaborative, sequential and intersubjective progression of dialogue.Media and Arts Technology programme, EPSRC Doctoral Training Centre EP/G03723X/

The disabilities of chronic schizophrenia: A search for neurological correlates

This study was designed to define in standardised fashion, the deficits of chronic schizophrenia and the correlates of these, and to evaluate two neurological parameters - spontaneous involuntary movements and lateral ventricular enlargement - in relation to the illness and its treatment. The study population comprised all those schizophrenics receiving long-term care in the one mental hospital who conformed to the St. Louis criteria for schizophrenia and who had been in-patients for at least 1 year continuously. This basic group consisted of 510 subjects. Analysis of standardised assessments covering mental state, cognition, neurological status and behaviour showed these patients to be extremely impaired. While historical correlates of functioning in particular spheres could be identified, the present clinical picture was in general related to the form of the initial illness and to factors reflecting the passage of time. Past physical treatment was not related to present deficits. Two broad patterns of disability were established. While the presence of prominent productive features in the mental state was not associated with the presence of deficits in other areas examined, prominent 'negative' features were related to the presence of cognitive impairment, extrapyramidal neurological signs and behavioural deterioration. Involuntary movements were assessed in 411 subjects using two standardised recording schedules. Abnormality was extremely common. The base-line prevalence of disorder in those with no history of neuroleptic exposure was comparable with that of those treated with neuroleptics, although with factors reflecting the passage of time accounted for, movement disorder was associated with past neuroleptic treatment. In addition however, the presence of abnormal movements related to features of the illness itself - namely 'negative' mental state features, cognitive impairment and behavioural deterioration. C.T. scans from 110 of the total population described above and controls representing non-institutionalised out-patient (18) and first episode (8) schizophrenics, institutionalised and out-patient manic-depressives (10 and 22 respectively) and neurotic out-patients (19), demonstrated that schizophrenia is associated with enlargement of the lateral ventricles, although only the institutionalised schizophrenics differed significantly from the neurotic controls. The group mean differences were not great and there was considerable overlap between groups. There was no evidence of a characteristic radiological change associated with schizophrenia. Lateral ventricular enlargement in schizophrenia was not consequent upon physical treatments administered in the past. The historical and examination variables which related to increased ventricular size in the long-stay schizophrenic population were few and the nature of certain relationships surprising. While behavioural deterioration and involuntary movements were significantly and linearly associated with ventricular enlargement, 'negative' mental state features, cognitive impairment and an absence of hallucinations were more commonly found in those at both extremes of ventricle size. The results suggest that although brain structure is genuinely altered in certain schizophrenics, the relationship between cerebral structure and clinical aspects of the condition is not straightforward. This study indicates that both neurological abnormality and structural brain change can be related to certain clinical features of established schizophrenia when other potentially relevant historical and treatment variables are accounted for. Such a general conclusion refers to statistical associations within large groups of patients and the relationship between neurology and psychopathology is complex. Nonetheless, the findings lend support to the view that in some patients at least, schizophrenia is a brain disorder whose cerebral basis can be inferred from the nature of some of the associated multiple deficits

Performing Authority in Byzantium. Bodies, Gestures, and Behaviour in the Practice and in the Literary Representation of Power

This research analyses the role of gesture, postures and bodily movements in Byzantine society and politics, with a particular attention to the imperial figure and through the theoretical lens provided by social sciences and performative studies. Far away from being a trivial one, the topic had been successfully addressed by the Greek-Roman and Middle Ages Western historical research, and only recently and occasionally had been put forward in the Byzantine field, where it remains an underestimated area of research. The present study wishes, first of all, to define the meaning and the values of bodily display and gesture (schema and schemata) in Byzantium, together with an analysis of the implications of the way in which the relation between body and soul was perceived, as well as of the rationale behind the use of physical movements. A more complex and comprehensive picture of the imperial body has emerged, unveiling its physical and performative dimension, its role in the ‘theater’ of a court potentially aware of the play, as well as its importance to understand the emperor’s divine and human nature. A review of the gestural occurrences has been conducted in the most exemplificative sources from Late Antiquity down to the Middle Byzantine period, and concluded with an exceptional case-study, the Chronographia of Michael Psellos