P. J. McCullagh

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Power spectral analysis (PSA) of the EEG was studied in healthy term and preterm neonates to establish the normal range with gestational age. Sixty healthy newborn infants from 26 to 41 weeks' gestation had PSA performed at 3 days of age. Five main frequency bands were studied: delta 1 (1 Hz or less), delta 2 (2-3 Hz), theta, alpha, and beta. A significant(More)
Spectral edge frequency (SEF) of the EEG was studied in 51 healthy neonates to assess its value as a measure of cerebral maturation. SEF was calculated as the frequency below which 95% of the power in the power spectrum resides. Summated SEF (sSEF) of 4 EEG channels correlated significantly with gestational age (r = 0.83). sSEF varied with behavioural state(More)
The application of image processing to the investigation of age-related macular degeneration (AMD) has focused on detecting focal drusen deposits in colour fundus images. This research investigates gradient vector flow (GVF) active contours for the detection of choroidal neovascularisation (CNV) from fundus fluorescein angiograms in exudative AMD, the most(More)
In the medical domain, one of the major challenges faced by the medical experts is the extraction of critical information for medical diagnosis. Specialized tools are necessary to assist the experts in diagnosing the diseases. Information retrieval is difficult in the case of ultrasound medical images due to its low resolution making diagnosis difficult.(More)
This paper describes a multimedia approach to sensory stimulation in psychophysiological studies. High resolution colour images are presented to a subject by a Delphi stimulus program, controlled by a data acquisition system which concurrently records cognitive Event Related Potentials from the subject. The acquisition PC is linked to the stimulus PC using(More)
An algorithm to assist in the computation of routine peripheral nystagmus slow phase velocity (SPV) has been implemented on an Apple based data acquisition system. Waveforms stored by the computer may be output to a dot matrix printer to complement conventional strip-chart recorder output. An estimate of SPV is available after each caloric session. Analysis(More)
This article provides a survey of published literature on technology developed to support people at the early stages of dementia during night time. Studies to date have focussed on Assistive Technology that can address monitoring in a sensor enriched home environment or provide location detection as a safety net. Additionally, studies have promoted therapy(More)
Human event-related potentials reflect cognitive processing, and are normally elicited by external events, such as acoustic sounds or visual stimuli. As such they provide an opportunity to study normal and abnormal brain function noninvasively, at sub-second resolution. Advances in multimedia technology permit specialists in informatics and neuropsychology(More)