If the outer hair cells are damaged, they do not regenerate. This results in a loss of sensitivity of hearing, as well as an abnormal perceived loudness in the aspect of the tonotopic spectrum that the damaged cells serve. Neural: characterised by degeneration of cells of the spiral ganglion. Strial/metabolic: characterised by atrophy of stria vascularis in all turns of cochlea. Located in the lateral wall of the cochlea, the stria vascularis contains sodium-potassium-ATPase pumps that are responsible for producing the endolymph resting potential. As individuals age, a loss of capillaries leads to the endolymphatic potential becoming harder to maintain, which brings a decrease in cochlear potential. Cochlear conductive: due to stiffening of the basilar membrane thus affecting its movement. This type of pathology has not been verified as contributing to presbycusis.In addition there are two other types:

Mixed
IndeterminateThe shape of the audiogram categorizes abrupt high-frequency loss (sensory phenotype) or flat loss (strial phenotype). The mainstay of SNHL is strial, with only about 5% of cases being sensory. This type of presbycusis is manifested by a low-frequency hearing loss, with unimpaired speech recognition. Classically, audiograms in neural presbycusis show a moderate downward slope into higher frequencies with a gradual worsening over time. A severe loss in speech discrimination is often described, out of proportion to the threshold loss, making amplification difficult due to poor comprehension.
Potassium phosphate is a generic term for the salts of potassium and phosphate ions including:
Monopotassium phosphate (KH2PO4) (Molar mass approx: 136 g/mol)
Dipotassium phosphate (K2HPO4) (Molar mass approx: 174 g/mol)
Tripotassium phosphate (K3PO4) (Molar mass approx: 212.27 g/mol)As food additives, potassium phosphates have the E number E340. == References ==