Anatomical and electrophysiological studies on early visual processing of polarized light in a stomatopod Haptosquilla pulchella

Abstract

Stomatopod crustaceans also known as mantis shrimps has one of the most sophisticated visual system of any animal known A functional specialized region termed midband which is composed of up to 6 rows of ommatidia and divides the eyes into two hemispheres was found in most of the mantis shrimps Equipped with the midband their compound eye is able to detect a diverse of visual information including 12 spectral channels 4 circular polarization channels and 4 linear polarization channels With such complex inputs it has been proposed that stomatopods may require a distinctive visual processing mechanism to decode the information By performing in vivo intracellular recording method with sharp-glass electrodes on neuropils of Haptosquilla pulchella I have examined electrophysiological responses of 89 interneurons to light pulse as well as linearly and circularly polarized light Satisfactory results were classified into 5 major functional groups which contained 3 groups of interneurons producing graded response including lamina monopolar cells (LMCs) tangential neurons as well as a new category of circular polarization analysis cell that has never been found in other animals and 2 groups of interneurons that were spiking neurons and phasic neurons which exhibited digital responses Though more works are required to fully decipher their visual physiology results in this study provide an initial insight into how visual signals are transmitted and processed in stomatopod crustaceans

Date of Award	2018 Dec 28
Original language	English
Supervisor	Tsyr-Huei Chiou (Supervisor)