Effect of cochlear implant n-of-m strategy on signal-to-noise ratio below which noise hinders speech recognition.

Speech recognition was measured in 24 normal-hearing subjects for unprocessed speech and for speech processed by a cochlear implant Advanced Combination Encoder (ACE) coding strategy in quiet and at various signal-to noise ratios (SNRs). All signals were low- or high-pass filtered to avoid ceiling effects. Surprisingly, speech recognition performance plateaus at approximately 22 dB SNR for both speech types, implying that ACE processing has no effect on the upper limit of the effective SNR range.

Lateral Inhibition in the Human Visual System in Patients with Glaucoma and Healthy Subjects: A Case-Control Study.

In glaucoma, the density of retinal ganglion cells is reduced. It is largely unknown how this influences retinal information processing. An increase in spatial summation and a decrease in contrast gain control and contrast adaptation have been reported.

Quantitative analysis of illusory movement: spatial filtering and line localization in the human visual system.

A narrow bar or line (width around 1 arcmin) between two fields of which the luminances are sinusoidally and in counterphase modulated in time appears to make an oscillatory movement. It is possible to annihilate this illusory movement with a real movement and thus to analyze this phenomenon quantitatively. Confirming previous studies, the amount of illusory movement (amplitude typically 10 arcsec) was proportional to the modulation depth of the fields and inversely proportional to the line width and the line contrast.