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Even deaf cats can end up unconscious after hearing the sound of crinkling tin foil, say vets

By Sarah Knapton, Science Editor 9:00PM BST 27 Apr 2015
[…]
Cats are known to hear sounds at ultrasonic frequencies and so may be more sensitive to high –pitched noise. However to make the condition even more puzzling, it was discovered that half of the cats were deaf, or had hearing impairments, which experts said was ‘paradoxical.

“The sounds responsible are high-pitched sounds, often relatively quiet sounds, with increasing loudness and persistence of a sound only serving to enhance the severity of the epileptic seizures,” said lead author, Dr Mark Lowrie of Davies Veterinary Specialists.

“Avoiding these sounds eliminated the seizures in 72 out of 96 cats.

“The reason for cats being so sensitive to these seemingly benign high-pitched sounds may have its origin in the ultrasonic hearing range of the species.

“Mice and rats communicate in the ultrasonic frequency range and it is believe that cats developed a secondary ultrasonic sensitive hearing range presumably as an evolutionary advantage in catching rats and mice, their natural prey.”

Previous studies have shown that even deaf cats can still hear in the ultrasonic range, around 40kHz.

“Therefore cats will appear deaf to us although complete hearing loss is not present,” added Dr Lowrie.
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