Introduction: Evaluation of local signal-to-noise ratio (SNR) is essential for many image-based analyses. Novel pulse sequence technology for dynamic imaging, such as HYPR [1], requires an alternative to conventional SNR estimation methods, since the SNR can vary in unexpected ways over very small distances; the typical assumption of near constant noise level throughout the object of interest [...

A procedure is developed to quantify and improve the signal-to-noise ratio (SNR) of Magnetic Resonance images. The image SNR is quanti ed using the correlation function of two independent acquisitions of an image. To test the performance of the quanti cation, SNR measurement data are tted to theoretically expected curves. The proposed correlation technique is also used to improve the SNR by est...

A procedure is developed to quantify and improve the signal-to-noise ratio (SNR) of magnetic resonance images. The image SNR is quantified using the correlation function of two independent acquisitions of an image. To test the performance of the quantification, SNR measurement data are fitted to theoretically expected curves. The proposed correlation technique is also used to improve the SNR by...

INTRODUCTION Accurate R2* measurements are critical for many quantitative imaging applications. R2* is estimated via mono-exponential fitting of signal decay within a series of gradient echo (GRE) images sampled at increasing TE. Root-sum-of-square (RSS) remains the most common approach to combine surface coil array images at each TE prior to the data fitting procedure. Rapid signal decay can r...

Yasuda M, Hikosaka O. Functional territories in primate substantia nigra pars reticulata separately signaling stable and flexible values. J Neurophysiol 113: 1681–1696, 2015. First published December 24, 2014; doi:10.1152/jn.00674.2014.—Gaze is strongly attracted to visual objects that have been associated with rewards. Key to this function is a basal ganglia circuit originating from the caudat...

OBJECTIVES In order to understand the communicative abilities of hearing impaired children in noisy situations and their communication problems, this study was undertaken to examine speech recognition at different background noise levels, and to compare how context cues in noisy situations affect speech recognition. METHODS Thirty-four children with severe/profound hearing impairment were enr...

Gaze is strongly attracted to visual objects that have been associated with rewards. Key to this function is a basal ganglia circuit originating from the caudate nucleus (CD), mediated by the substantia nigra pars reticulata (SNr), and aiming at the superior colliculus (SC). Notably, subregions of CD encode values of visual objects differently: stably by CD tail [CD(T)] vs. flexibly by CD head ...

Neurons use glucose to fuel glycolysis and provide substrates for mitochondrial respiration, but neurons can also use alternative fuels that bypass glycolysis and feed directly into mitochondria. To determine whether neuronal pacemaking depends on active glucose metabolism, we switched the metabolic fuel from glucose to alternative fuels, lactate or β-hydroxybutyrate, while monitoring the spont...

In this contribution we investigate a priori signal-to-noise ratio (SNR) estimation, a crucial component of a single-channel speech enhancement system based on spectral subtraction. The majority of the state-of-the art a priori SNR estimators work in the power spectral domain, which is, however, not confirmed to be the optimal domain for the estimation. Motivated by the generalized spectral sub...