Figure 4.

Synaptic loss and ribbon synapse degradation. The ribbon synapse complex is organized so, those neurons with a low stimulation rate are concentrated in the modiolar site, while those with a higher stimulation rate are concentrated in the pillar site. Modiolar neurons are the most susceptible cells to noise- and aging-induced damage. Their synaptic degeneration leads to neuronal death. The remaining neurons modify their synaptic connection to compensate the neuronal population reduction. However, the process can be reversed, before the SGN death, with NT-3 and BDNF overexpression. Figure modified from [8]