Simplify the following text for a Grade 11 native English-speaking person.
Original: Ultrasonic hearing can occur if ultrasound is fed directly into the skull bone and reaches the cochlea through bone conduction without passing through the middle ear .
Simplified: If ultrasound is fed directly into the skull bone and reaches the cochlea without passing through the middle ear , much higher frequencies ( up to about 200 kHz ) can be heard .