<unk>  is caused by malfunctions in neurotransmission from rod and cone photoreceptors to bipolar cells in the retina. At this first synapse, information from photoreceptors is divided into two channels: ON and OFF. The ON pathway detects<unk>  onset, while the OFF pathway detects<unk>  offset. The malfunctions in<unk> 1 specifically affect the ON pathway, by hindering the ability of ON-type bipolar cells to detect neurotransmitter released from photoreceptors. Rods, which are responsible for low-light vision, make contacts with ON-type bipolar cells only, while, cones, which are responsible for bright-light vision, make contacts with bipolar cells of both ON an OFF subtypes. Because the low-light sensing rods feed only into the ON pathway, individuals with<unk> 1 typically have problems with<unk>  vision, while vision in well-lit conditions is spared. In<unk> 2, release of neurotransmitter from photoreceptors is impaired, leading to involvement of both ON and OFF pathways. The electroretinogram (ERG) is an important tool for diagnosing<unk> . The ERG a-wave, which reflects the function of the phototransduction cascade in response to a<unk>  flashes, is typically normal in<unk>  patients, although in some cases phototransduction is also affected, leading to a reduced a-wave. The ERG b-wave, which primarily reflects the function of ON-bipolar cells, is greatly reduced in<unk> 2 cases, and completely absent in<unk> 1 cases.
Congenital stationary night blindness
Ametropic amblyopia
Toxic amblyopia
Scintillating scotoma
Optic nerve hypoplasia
Computer vision syndrome
Cat eye syndrome
Motion-induced blindness