On the Definition of Signal-To-Noise Ratio and Contrast-To-Noise Ratio for fMRI Data

On the Definition of Signal-To-Noise Ratio and Contrast-To-Noise Ratio for fMRI Data

Signal-to-noise ratio, the ratio between signal and noise, is a quantity that has been well established for MRI data but is still subject of ongoing debate and confusion when it comes to fMRI data. fMRI data are characterised by small activation fluctuations in a background of noise. Depending on how the signal of interest and the noise are identified, signal-to-noise ratio for fMRI data is rep...

Effect of signal to noise ratio on the speech perception ability of older adults

Background: Speech perception ability depends on auditory and extra-auditory elements. The signal-to-noise ratio (SNR) is an extra-auditory element that has an effect on the ability to normally follow speech and maintain a conversation. Speech in noise perception difficulty is a common complaint of the elderly. In this study, the importance of SNR magnitude as an extra-auditory effect on speech...

On Signal to Noise Ratio Tradeoffs in fMRI

When planning an fMRI experiment, it is desirable to optimize the SNR to maximize the statistical return on scan time investment. At first glance, the tradeoffs may seem unclear. As more slices are acquired, the TR needed to fit in the slices increases linearly. With longer TR the flip angle and degree of magnetization recovery between pulses both increase, leading to higher signal. However, at...

Digital Transmission : Carrier - to - Noise Ratio , Signal - to - Noise Ratio , and Modulat ion Error Ratio

Signal-to-Noise Ratio Estimation

Of the many measures that characterize the performance of a communication receiver, signal-to-noise ratio (SNR) is perhaps the most fundamental in that many of the other measures directly depend on its knowledge for their evaluation. In the design of receivers for autonomous operation, it is desirable that the estimation of SNR take place with as little known information as possible regarding o...