Early symptoms of auditory nerve damage may involve hearing or balance problems as the auditory system communicates information concerning sound and body positioning to the brain. Symptoms include tinnitus, sensorineural hearing loss, dizziness, or vertigo with or without vomiting and nausea.owever, this is not usually the case. Most deaf people have conductive hearing loss due to damage in the middle ear structures. Neural hearing loss due to auditory nerve damage is much less common than conductive hearing loss and is usually irreversible.
The permanently frozen ground in the northern latitudes is called permafrost. The layer closest to the surface that thaws during the summer is also part of the permafrost, but is called the active layer.
Rock which retains water in this way is called an aquifer. Rock types which can hold water include chalk, limestone and sandstone. Rock types which do not hold water but can prevent water moving out of a permeable rock type include granite, basalt and mudstone. Groundwater supplies springs and wells and, when there has been a period with little rain, it is often groundwater that maintains flow in rivers rather than surface drainage from land.