Automatic design of neuromarkers for obsessive compulsive disorder characterisation

This bacherlor thesis proposes a new paradigm to discover biomarkers capable of characterizing obsessive-compulsive disorder (OCD) by means of machine learning methods. These biomarkers, named neuromarkers, will be obtained through the analysis of sets of magnetic resonance images of the brains of OCD patients and healthy control subjects. The design of the neuromarkers stems from a method for the automatic discovery of clusters of voxels, distributed in separate brain regions, relevant to OCD. This method was recently published by Dr. Emilio Parrado Hernández, Dr. Vanessa Gómez Verdejo and Dr. Manel Martínez Ramón. With these clusters as a starting point, we will de ne the neuromarkers as a set of measurements describing features of these individual regions. Then we will perform a selection of these neuromarkers, using state of the art feature selection techniques, to arrive at a reduced, relevant and intuitive set. The results will be sent to Dr. Carles Soriano Mas at the Bellvitge University Hospital in Barcelona, Spain. His feedback will be used to determine the e cacy of our neuromarkers and their usefulness for psychiatric analysis. The main goal of the project is to come up with a set of neuromarkers for OCD characterisation that are easy to interpret and handle by the psychiatric community. A paper presenting the methods and results described in this bachelor thesis, of which the student is the main author, has been submitted and accepted for presentation in the 2014 European Congress of Machine Learning (ECML/PKDD 2014). The ECML reported a 23.8% paper acceptance rate for 2014.Ingeniería de Sistemas Audiovisuale

Detección de TOC en escenarios multicéntricos mediante el uso de PRoNTo

Este Trabajo Fin de Grado pretende detectar, a través de imágenes de resonancia magnética estructural, la enfermedad neurológica del Trastorno Obsesivo Compulsivo (TOC). Para ello, se utiliza la herramienta de aprendizaje máquina PRoNTo (v.1.1), basada en Matlab. Se trata de un problema de clasificación binaria donde tenemos datos de pacientes enfermos de TOC y datos de controles sanos. Como el objetivo es encontrar la mejor solución para nuestro problema, se han realizado diversos experimentos. En primer lugar, tratando de encontrar el modelo de clasificación más adecuado para nuestro caso. Los experimentos se han realizado con dos modelos de aprendizaje máquina: la máquina de vectores de soporte y el proceso gaussiano. Además, se ha tratado de evaluar las consecuencias de incluir algunos preprocesados de datos, ofrecidos por PRoNTo, y alguna máscara de selección de vóxeles que delimite las regiones de interés. En este documento se describen todos los experimentos mencionados anteriormente, con base teórica, junto a sus resultados correspondientes.Ingeniería de Sistemas Audiovisuale

The Role of Amygdala Subregions in the Neurobiology of Social Anxiety Disorder

Social anxiety is characterised by fear and/or avoidance of social situations in which an individual may be scrutinised by others. Social anxiety is thought to exist as a spectrum, with individuals on the high-end experiencing frequent and severe anxiety in the context of social situations. When severe social anxiety is accompanied by distress and functional impairment, a diagnosis of social anxiety disorder (SAD) can be made. SAD is a prevalent and debilitating disorder that can be unremitting and pervasive in the absence of intervention. Current psychotherapeutic and pharmacotherapeutic treatments for SAD demonstrate limited efficacy in remitting symptoms. Therefore, it is important to achieve a better understanding of the neurobiological mechanisms implicated in this disorder and identify potential neural treatment targets to develop more efficacious treatments. This thesis aimed to further investigate the neurobiological mechanisms implicated in SAD (vs. controls) and the associations between neural functioning and social anxiety as a dimensional symptom, with a focus on the amygdala and four of its subregions (the amygdalostriatal, basolateral, centromedial, and superficial subregions). This was due to previous findings in the neuroimaging literature in SAD having consistently implicated the amygdala, albeit with mixed findings of both increased and decreased functioning in those with SAD compared to controls. In the literature to date, however, most studies had examined the amygdala as a singular homogenous region due to methodological limitations in being able to examine the functionally and structurally distinct subnuclei that make up this region. By examining the amygdala subregions through the use of multiband functional magnetic resonance imaging (fMRI), this thesis additionally sought to determine whether the mixed findings in the literature to date may be a result of amygdala subregion-specific activity and connectivity patterns. This was achieved through three research studies. Firstly, Study 1 involved a comprehensive systematic review that summarised the literature on resting-state neuroimaging in SAD with a focus on fMRI studies and findings specific to the amygdala and its subregions (Chapter 3). This was followed by two empirical studies which investigated the role of the amygdala and its subregions during resting-state (Study 2) and emotion processing (Study 3) fMRI paradigms (Chapters 5 and 6, respectively). Findings from the systematic review (Study 1) highlighted the mixed findings in the resting-state neuroimaging literature in SAD to date, along with methodological limitations relating to neuroimaging acquisition and analysis. The empirical studies sought to address these limitations and demonstrated differing amygdala subregion activity and connectivity patterns at rest and during emotion processing. In the resting-state fMRI study (Study 2), there were no statistically significant differences in functional connectivity of the amygdala and its subregions in those with SAD compared to controls. However, social anxiety severity was found to be positively associated with connectivity between the superficial subregion and the supramarginal gyrus. The superficial subregion, along with the basolateral and centromedial subregions, were also implicated in the task-based emotion processing fMRI study (Study 3). In response to happy, angry, and fearful faces, those with SAD (vs. controls) had hyperactivation of the superficial subregion, hypoconnectivity between the superficial subregion and the precuneus, and hyperconnectivity between the basolateral subregion and broader brain regions (i.e., the pre/postcentral gyrus and the supramarginal gyrus). Additionally, social anxiety severity was positively associated with superficial and centromedial activation. Overall, the findings from this thesis provide novel information to the current understanding of the neurobiology of SAD by demonstrating amygdala subregion-specific alterations. This has important implications for research, theory, and clinical practice that are detailed in the thesis discussion (Chapter 7). Briefly, in terms of research, findings from the thesis provide support for the continuing investigation of SAD using both dimensional and categorical approaches. This was evident by the findings from the two empirical papers which demonstrated positive associations between subregional activity and connectivity patterns and social anxiety severity. With regards to theory, differences in neural patterns that were observed at rest (Study 2) and during emotion processing (Study 3) provide support for distinct neurobiological models to be constructed based on whether those with SAD are in the absence or presence of social stimuli. This is in contrast to the most recently proposed neurobiological model of SAD which was informed by a combination of resting-state and task-based fMRI data. Finally, with regards to clinical practice, the findings from this thesis provide preliminary evidence of the superficial, basolateral, and centromedial subregions of the amygdala as being potential treatment targets that can be used to inform the development of more efficacious treatments for SAD

TMS application in both health and disease

Transcranial magnetic stimulation (TMS) can be useful for therapeutic purposes for a variety of clinical conditions. Numerous studies have indicated the potential of this noninvasive brain stimulation technique to recover brain function and to study physiological mechanisms. Following this line, the articles contemplated in this Research Topic show that this field of knowledge is rapidly expanding and considerable advances have been made in the last few years. There are clinical protocols already approved for Depression (and anxiety comorbid with major depressive disorder), Obsessive compulsive Disorder (OCD), migraine headache with aura, and smoking cessation treatment but many studies are concentrating their efforts on extending its application to other diseases, e.g., as a treatment adjuvant. In this Research Topic we have the example of using TMS for pain, post-stroke depression, or smoking cessation, but other diseases/injuries of the central nervous system need attention (e.g., tinnitus or the surprising epilepsy). Further, the potential of TMS in health is being explored, in particular regarding memory enhancement or the mapping of motor control regions, which might also have implications for several diseases. TMS is a non-invasive brain stimulation technique that can be used for modulating brain activation or to study connectivity between brain regions. It has proven efficacy against neurological and neuropsychiatric illnesses but the response to this stimulation is still highly variable. Research works devoted to studying the response variability to TMS, as well as large-scale studies demonstrating its efficacy in different sub-populations, are therefore of utmost importance. In this editorial, we summarize the main findings and viewpoints detailed within each of the 12 contributing articles using TMS for health and/or disease applications.publishe

Do informal caregivers of people with dementia mirror the cognitive deficits of their demented patients?:A pilot study

Recent research suggests that informal caregivers of people with dementia (ICs) experience more cognitive deficits than noncaregivers. The reason for this is not yet clear. Objective: to test the hypothesis that ICs ‘mirror' the cognitive deficits of the demented people they care for. Participants and methods: 105 adult ICs were asked to complete three neuropsychological tests: letter fluency, category fluency, and the logical memory test from the WMS-III. The ICs were grouped according to the diagnosis of their demented patients. One-sample ttests were conducted to investigate if the standardized mean scores (t-scores) of the ICs were different from normative data. A Bonferroni correction was used to correct for multiple comparisons. Results: 82 ICs cared for people with Alzheimer's dementia and 23 ICs cared for people with vascular dementia. Mean letter fluency score of the ICs of people with Alzheimer's dementia was significantly lower than the normative mean letter fluency score, p = .002. The other tests yielded no significant results. Conclusion: our data shows that ICs of Alzheimer patients have cognitive deficits on the letter fluency test. This test primarily measures executive functioning and it has been found to be sensitive to mild cognitive impairment in recent research. Our data tentatively suggests that ICs who care for Alzheimer patients also show signs of cognitive impairment but that it is too early to tell if this is cause for concern or not

Measuring Behavior 2018 Conference Proceedings

These proceedings contain the papers presented at Measuring Behavior 2018, the 11th International Conference on Methods and Techniques in Behavioral Research. The conference was organised by Manchester Metropolitan University, in collaboration with Noldus Information Technology. The conference was held during June 5th – 8th, 2018 in Manchester, UK. Building on the format that has emerged from previous meetings, we hosted a fascinating program about a wide variety of methodological aspects of the behavioral sciences. We had scientific presentations scheduled into seven general oral sessions and fifteen symposia, which covered a topical spread from rodent to human behavior. We had fourteen demonstrations, in which academics and companies demonstrated their latest prototypes. The scientific program also contained three workshops, one tutorial and a number of scientific discussion sessions. We also had scientific tours of our facilities at Manchester Metropolitan Univeristy, and the nearby British Cycling Velodrome. We hope this proceedings caters for many of your interests and we look forward to seeing and hearing more of your contributions