Development and application of magnetoencephalographic methods in the investigation of the human visual system

This thesis is an exploration of the organisation and functioning of the human visual system using the non-invasive functional imaging modality magnetoencephalography (MEG). Chapters one and two provide an introduction to the ‘human visual system and magnetoencephalographic methodologies. These chapters subsequently describe the methods by which MEG can be used to measure neuronal activity from the visual cortex. Chapter three describes the development and implementation of novel analytical tools; including beamforming based analyses, spectrographic movies and an optimisation of group imaging methods. Chapter four focuses on the use of established and contemporary analytical tools in the investigation of visual function. This is initiated with an investigation of visually evoked and induced responses; covering visual evoked potentials (VEPs) and event related synchronisation/desynchronisation (ERS/ERD). Chapter five describes the employment of novel methods in the investigation of cortical contrast response and demonstrates distinct contrast response functions in striate and extra-striate regions of visual cortex. Chapter six use synthetic aperture magnetometry (SAM) to investigate the phenomena of visual cortical gamma oscillations in response to various visual stimuli; concluding that pattern is central to its generation and that it increases in amplitude linearly as a function of stimulus contrast, consistent with results from invasive electrode studies in the macaque monkey. Chapter seven describes the use of driven visual stimuli and tuned SAM methods in a pilot study of retinotopic mapping using MEG; finding that activity in the primary visual cortex can be distinguished in four quadrants and two eccentricities of the visual field. Chapter eight is a novel implementation of the SAM beamforming method in the investigation of a subject with migraine visual aura; the method reveals desynchronisation of the alpha and gamma frequency bands in occipital and temporal regions contralateral to observed visual abnormalities. The final chapter is a summary of main conclusions and suggested further work.

The making of an ideology of the third way:the evolution of christian democracy in Germany (with special reference to 1945-49)

This study investigates the search for the third way in the history of German Christian Democracy. Today, in the United Kingdom, the 'third way' is seen as a new phenomenon, a synthesis of post-war belief in the welfare state and neo-liberal conservatism. Yet it insufficiently acknowledges that the origins of third way thinking, the marriage of social justice with free market economics, of individualism with collective responsibility, are found in the early philosophies of Catholic Social Theory and Protestant Social Ethical Teaching in Germany. This study shows that in the hundred years from the 1840s to the end of the 1940s, there were Catholic and Protestant socio-ethical thinkers and political reformists in Germany who attempted to bridge the philosophical differences between liberalism and socialism, to develop a socio-economic order based on Christian moral values. It will focus on the period 1945-1949, when the CDU was founded as the first interdenominational, Christian party. The study provides the first comprehensive account of the political debates in Christian democratic groups in the Soviet, British, French and American allied occupied zones, also giving equal attention to the contribution from the Protestant wing, alongside the more widely acknowledged role of Catholics in the birth of the CDU. It examines how Christian Democrats envisaged correcting the aberrations of German history, by uniting all social classes and Christian religions in one all-embracing Volkspartei, and transforming party politics from its earlier obsession with sectarian and ideological interests towards a more pragmatic 'third way' programme. The study argues that through the making of its ideology, the CDU modified the nation's understanding of its history, re-interpreted its traditions, and redefined the meaning and perception of established political philosophies. This reveals how the ambiguity of political terminology, and the flexible practice of 'third way' politics, were an invaluable political resource in the CDU's campaign for unity, ideological legitimisation and political power.