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What role do new, networked and pervasive technologies play in changing individual and collective memory processes? Many recent debates have focused on whether we are in the online era remembering 'less' or 'more' - informed, perhaps, by a tendency to think of memory spatially and quantifiably as working like an archive. Drawing on the philosophical theorising of Henri Bergson and its development through Gilbert Simondon, this thesis makes two interventions into the field. Firstly, conceptually, it establishes a process-based approach to perception, memory and consciousness in a shift away from the archive metaphor - thinking memory not as informing 'knowledge of the past' but 'action in duration'. It situates the conscious, living being as transindividual - affectively relational to its perceived bodily and social environments, through psychic and collective individuation respectively. Moreover, it considers technologies as forms of transindividual extension of consciousness. Furthermore, it proposes the 'antimetaphor' of the anarchive as a conceptual tool with which to understand these durationbased, bodily and technological, action-oriented processes. Secondly, methodologically, it advocates a rephrasing of the question from how much we are remembering to how we are remembering differently. Armed now with a developed theoretical position and methodological approach, the thesis explores through three case-study chapters how personal and more historical pasts may be remembered, individually and more collectively, through new, prevalent technologies of memory such as search engines, forums and social-media sites. Analysing the material experiences of remembering, as well as examining the economic drives of the platforms and wider actors, and the resulting socio-political implications, the thesis sets out the original argument of a contemporary struggle for memory: a complex negotiation of tensions between agencies of the body, the social, and the multifarious and interconnected socio-political and economic interests of the technological platforms and hybridised media systems through which contemporary remembering increasingly takes place.

The clinical outcomes for epilepsy and brain tumour surgery depend on the extent of resection. Neurosurgeons frequently rely on subjective assessment of stiffness and adherence to achieve maximal resection. However, due to similarity in tactile texture and visual appearance of these lesions to normal brain, this can lead to inadequate resection. Magnetic resonance imaging (MRI) has not completely solved this problem for various reasons, including the existence of MRI-negative lesions. Shear wave elastography (SWE) is an ultrasound-based quantitative elasticity imaging technique that provides an objective assessment of stiffness, which has not previously been applied intraoperatively during neurosurgery. This thesis describes the optimisation and assessment of implementing intraoperative SWE in neurosurgery. The aims of the work described in this thesis were to validate SWE measurements; to optimise intraoperative applications by investigating the artefacts of SWE; to evaluate SWE performance in detecting epileptogenic lesions, residual tumour and slippery boundaries; and to determine the histopathological correlation with SWE measurements. Using gelatine phantoms and post-mortem mouse brains, SWE measurements were validated. Through phantom models and ex vivo porcine brains and spinal cords, the factors affecting SWE measurements were established and SWE settings optimised. In addition, novel features of slippery tumour-brain interface were demonstrated in vitro and confirmed intraoperatively. Clinical implementation of SWE in epilepsy (38 patients) and brain tumour surgery (34 patients), demonstrated SWE’s capability in differentiating epileptogenic lesions (p < 0.001) and brain tumours (p=0.003) from normal brain. SWE was shown to be superior to MRI in detecting epileptogenic lesions (p=0.001), in particular MRI-negative cases where SWE managed to demonstrate lesions in 4 cases with positive histology. For detecting residual tumour, SWE was shown to be superior to surgeons’ opinion (p=0.001), and similar to MRI (p=1.000) and intraoperative B-mode ultrasound (p=0.727). Histopathologically, there was no correlation with SWE measurements, except for proliferation (p=0.007). In conclusion, this thesis demonstrated potential patient benefit of integrating intraoperative SWE into neurosurgical practice, and therefore, a compelling reason to continue development and optimisation of this technology.