Search results for "Audio frequency"
showing 3 items of 3 documents
Echo-sounding can discriminate between fish and macroinvertebrates in fresh water
2008
SUMMARY 1. Acoustic scattering from fish and macroinvertebrates was studied in a boreal Finnish lake at three echosounder frequencies (38, 120 and 200 kHz). Split-beam transducers with partly overlapping 7� beams were employed. Acoustic, fish and invertebrate sampling were undertaken simultaneously. Vertical gradients of temperature and oxygen concentration were measured during the exercise. 2. At all frequencies, a narrow scattering layer coincided with the thermocline. At 38 kHz, fish were detected well with practically no reverberation from invertebrates while 200 kHz detected both fish and invertebrates. 3. Minor differences in the magnitude of acoustic scattering from fish were found b…
Dynamic Fast Imaging Employing Steady State Acquisition Magnetic Resonance Imaging of the Vocal Tract in One Overtone Male Singer: Our Preliminary Ex…
2022
Summary Aims To demonstrate physiological changing of vocal tract's structures during overtone singing with commercial magnetic resonance imaging (MRI) Fast Imaging Employing Steady State Acquisition (FIESTA) dynamic sequence. Methods and Materials A 1.5 T MRI with a 16 channel head-and-neck coil and a FIESTA sequence were used. A temporal resolution of 0.155 sec (7 image/s). A single professional singer was studied. The MR acquisition is made while the singer performed a predetermined singing sequence. Three different overtone singing techniques were examined (L-technique, J-technique, and NG technique) and one effect (Ezengileer) applied to L-technique. For each overtone technique we eval…
Deviance detection in sound frequency in simple and complex sounds in urethane-anesthetized rats
2019
Mismatch negativity (MMN), which is an electrophysiological response demonstrated in humans and animals, reflects memory-based deviance detection in a series of sounds. However, only a few studies on rodents have used control conditions that were sufficient in eliminating confounding factors that could also explain differential responses to deviant sounds. Furthermore, it is unclear if change detection occurs similarly for sinusoidal and complex sounds. In this study, we investigated frequency change detection in urethane-anesthetized rats by recording local-field potentials from the dura above the auditory cortex. We studied change detection in sinusoidal and complex sounds in a series of …