The studies are part of a new trend: to look for integration of response rather than investigating each part/function separately. The fMRI studies show that touch has a wide impact on the brain, influencing our sensations, our movements, our thought processes and our capacity to learn new movements.
Dogs are most sensitive to sounds in the frequency range from 500 to 16kHz. REVERBERATION TIME. This is the time for a sound to decay to 60dB. Kennels by their nature have poor acoustic properties; hard, smooth surfaces do not absorb noise, therefore any noise generated tends to reverberate inside the building.
The frequency of most dog whistles is within the range of 23 to 54 kHz, so they are above the range of human hearing, although some are adjustable down into the audible range. To human ears, a dog whistle makes only a quiet hissing sound. The advantage of the dog whistle is that it doesn't produce a loud irritating noise for humans that a normal whistle would produce, so it can be used to train or command animals without disturbing nearby people.