I really don't know and I'm no medical expert, but if your text has to do with
the auditory cortex, this translation might be right: Sylvian fossa. I'm basing this only on the fact that one translation of Furche is furrow.

"The nerve fibres carrying sound signals lead to different parts of the auditory cortex depending on the frequencies they carry. The auditory cortex lies in a deep furrow called the Sylvian fossa. The high tones terminate deep within the Sylvian fossa while the low tones end near the outer surface.