A. C. Thompson

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A Monte Carlo model has been developed to simulate light transport and absorption in neural tissue during infrared neural stimulation (INS). A range of fiber core sizes and numerical apertures are compared illustrating the advantages of using simulations when designing a light delivery system. A range of wavelengths, commonly used for INS, are also compared(More)
A model of infrared neural stimulation (INS) has been developed to allow the temporal characteristics of different stimulation parameters and geometries to be better understood. The model uses a finite element approach to solve the heat equation and allow detailed analysis of heat during INS with both microsecond and millisecond laser pulses. When compared(More)
Efficient filtering of sigma-delta bit-streams using a finite-impulse response (FIR)-like digital filter is presented. The filter combines a lowpass sigma-delta modulator system and a ternary FIR filter. Unlike conventional FIR filters, the combination of the two components allows a bit stream to be filtered, with the output being retained in single-bit(More)
A model to simulate heating as a result of pulse repetitions during infrared neural stimulation (INS), with both single- and multiple-emitters is presented. This model allows the temperature increases from pulse trains rather than single pulses to be considered. The model predicts that using a stimulation rate of 250 Hz with typical laser parameters at a(More)
At present there is some debate as to the processes by which infrared neural stimulation (INS) activates neurons in the cochlea, as the lasers used for INS can potentially generate a range of secondary stimuli e.g. an acoustic stimulus is produced when the light is absorbed by water. To clarify whether INS in the cochlea requires functioning hair cells and(More)
Our capacity to interface with the nervous system remains overwhelmingly reliant on electrical stimulation devices, such as electrode arrays and cuff electrodes that can stimulate both central and peripheral nervous systems. However, electrical stimulation has to deal with multiple challenges, including selectivity, spatial resolution, mechanical stability,(More)
OBJECTIVE Recent research has demonstrated that nerves can be stimulated by transient heating associated with the absorption of infrared light by water in the tissue. There is a great deal of interest in using this technique in neural prostheses, due to the potential for increased localization of the stimulus and minimization of contact with the tissue.(More)
INTRODUCTION Electrical stimulation has long been the most effective strategy for evoking neural activity from bionic devices and has been used with great success in the cochlear implant to allow deaf people to hear speech and sound. Despite its success, the spread of electrical current stimulates a broad region of neural tissue meaning that contemporary(More)
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