H Goelz | PubMed Health

PubMed2003

EMMA--an eye movement measurement and analysis system.

A system has been developed for stimulation, recording and analysis of a wide range of eye movements. Eye movements are stimulated with an LED bar or a video projector under the control of a PC. The eye movements are measured using a scleral reflection technique (IRIS instrument), and sampled and stored on a PC. A range of tests have been developed to measure saccadic and smooth pursuit eye movements. A variety of tools have been developed to assist in the analysis of the data. Several research studies have ably demonstrated the utility and versatility of the system.

Equipment Design↗

PubMed2000

Wavelet analysis of transient biomedical signals and its application to detection of epileptiform activity in the EEG.

Wavelet based signal analysis provides a powerful new means for the analysis of nonstationary signals such as the human EEG. The properties of the discrete wavelet transform are reviewed in illustrated application examples. The continuous wavelet transform is shown to provide better detection and representation of isolated transients. An approach to extract features of edges and transients from the continuous wavelet transform is outlined. Matching pursuit is presented as a more general transform method that covers both transients and oscillation spindles. A statistical model for the continuous wavelet transform of background EEG is found. A spike detection system based on this background model is presented. The performance of this detection system has been assessed in a preliminary clinical study of 11 EEG recordings containing epileptiform activity and shown to have a sensitivity of 84% and a selectivity of 12%. The spatial context of epileptiform activity will be incorporated to improve system performance.

Brain↗