Putative targets of direction-selective retinal ganglion cells in the tectum opticum of cyprinid fish.

Putative targets of direction-selective retinal ganglion cells in the tectum opticum of cyprinid fish. Brain Res. 2018 Dec 05;: Authors: Damjanović I, Maximov PV, Aliper AT, Zaichikova AA, Gačić Z, Maximova EM Abstract Responses of direction selective (DS) units of retinal and tectal origin were recorded extracellularly from the tectum opticum (TO) of immobilized fish. The data were collected from three cyprinid species - goldfish, carp and roach. Responses of the retinal DS ganglion cells (GCs) were recorded from their axon terminals in the superficial layers of TO. According to their preferred directions DS GCs, characterized by small receptive fields (3-8°), can be divided in three distinct groups, each group containing ON and OFF subtypes approximately in equal quantity. Conversely, direction-selective tectal neurons (DS TNs), recorded at two different tectal levels deeper than the zone of retinal DS afferents, are characterized by large receptive fields (up to 60°) and are indifferent to any sign of contrast i.e. can be considered as ON-OFF type units. Fish DS TNs unlike the retinal DS GCs, select four preferred directions. Three types of tectal DS units prefer practically the same directions as those already selected on the retinal level - caudo-rostral, dorso-ventral and ventro-dorsal. The fact that three preferred directions of DS GCs and DS TNs coincide allows us to assume that three types of DS GCs are input neurons fo...
Source: Brain Research - Category: Neurology Authors: Tags: Brain Res Source Type: research