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Lamina (neuropil)
The lamina is the most peripheral neuropil of the insect visual system. There are twelve distinct neuron classes in the lamina: the lamina monopolar cells L1-L5, two GABA GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ...ergic feedback neurons (C2 and C3), two wide-field feedback neurons (Lawf1 and Lawf2), lamina intrinsic amacrine neurons (Lai) and the T1 basket cell. The outer photoreceptors, R1-R6, terminate in the lamina, where they form tetrad synapses with L1, L2, L3, and Lai. The lamina was the first portion of the nervous system of Drosophila to be reconstructed, thus starting the field of Drosophila connectomics. However the methods used were largely manual and further progress awaited more automated techniques. References Insect anatomy Visual perception ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuropil
Neuropil (or "neuropile") is any area in the nervous system composed of mostly unmyelinated axons, dendrites and glial cell processes that forms a synaptically dense region containing a relatively low number of cell bodies. The most prevalent anatomical region of neuropil is the brain which, although not completely composed of neuropil, does have the largest and highest synaptically concentrated areas of neuropil in the body. For example, the neocortex and olfactory bulb both contain neuropil. White matter, which is mostly composed of myelinated axons (hence its white color) and glial cells, is generally not considered to be a part of the neuropil. Neuropil (pl. neuropils) comes from the Greek: ''neuro'', meaning "tendon, sinew; nerve" and ''pilos'', meaning "felt". The term's origin can be traced back to the late 19th century. Location Neuropil has been found in the following regions: outer neocortex layer, barrel cortex, inner plexiform layer and outer plexiform lay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Visual System
The optic(al) lobe of arthropods is a structure of the protocerebrum that sits behind the arthropod eye (mostly compound eyes) and is responsible for the processing of the visual information. It is made up of three layers: ;Lamina (ganglionaris): responsible for contrast enhancement through lateral inhibition ;Medulla: processes movement and shows movement direction sensitivity. Possesses local motion detectors ;Lobula: integrates information from large areas of the visual field to abstract visual information and object recognition Object recognition – technology in the field of computer vision for finding and identifying objects in an image or video sequence. Humans recognize a multitude of objects in images with little effort, despite the fact that the image of the ... :;Lobula plate: wide-field motion vision References {{insect-stub Arthropod anatomy Animal nervous system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamina Monopolar Cell
Lamina monopolar cells are a class of neurons in the most peripheral neuropil of the arthropod visual system, the lamina Lamina may refer to: People * Saa Emerson Lamina, Sierra Leonean politician * Tamba Lamina, Sierra Leonean politician and diplomat Science and technology * Planar lamina, a two-dimensional planar closed surface with mass and density, in mathem .... Most insects, including flies, have five distinct classes lamina monopolar cells: L1, L2, L3, L4, and L5. L1, L2, L3, receive direct synaptic input from the photoreceptors in the lamina, and send axons into the second-order neuropil of the visual system, the medulla. References {{Insect-anatomy-stub Insect anatomy Visual perception ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABA
GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GABA is sold as a dietary supplement in many countries. It has been traditionally thought that exogenous GABA (i.e., taken as a supplement) does not cross the blood–brain barrier, but data obtained from more recent research (2010s) in rats describes the notion as being unclear. The carboxylate form of GABA is γ-aminobutyrate. Function Neurotransmitter Two general classes of GABA receptor are known: * GABAA in which the receptor is part of a ligand-gated ion channel complex * GABAB metabotropic receptors, which are G protein-coupled receptors that open or close ion channels via intermediaries (G proteins) Neurons that produce GABA as their output are called GABAergic neurons, and have chiefly inhibitory action at receptors in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simple Eye In Invertebrates
A simple eye or ocellus (sometimes called a pigment pit) is a form of eye or an optical arrangement which has a single lens without the sort of elaborate retina that occurs in most vertebrates. These eyes are called "simple" to distinguish them from " compound eyes", which have multiple lenses. They are not necessarily simple in the sense of being uncomplicated or basic. The structure of an animal's eye is determined by the environment in which it lives, and the behavioural tasks it must fulfill to survive. Arthropods differ widely in the habitats in which they live, as well as their visual requirements for finding food or conspecifics, and avoiding predators. Consequently, an enormous variety of eye types are found in arthropods to overcome visual problems or limitations. Use of the term ''simple eye'' is flexible, and must be interpreted in proper context; for example, the eyes of most large animals are '' camera eyes'' and are sometimes considered "simple" because a sing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ian Meinertzhagen
Ian Anthony Meinertzhagen (born 1944, in Kent, United Kingdom) is a Canadian neurobiologist, a University Research Professor at Dalhousie University, in Halifax, Nova Scotia and Senior Fellow at the Janelia Research Campus of the Howard Hughes Medical Institute in Ashburn, Virginia. He is a graduate of the Universities of Aberdeen (BSc) and St. Andrews (PhD, DSc) and undertook postdoctoral work at the Australian National University and Harvard University. His research has pioneered studies on simple nervous systems of invertebrate species, especially the ''Drosophila'' visual system and the diminutive chordate nervous system of the ascidian tadpole larva. Publications His most cited publications are: *R.Steven Stowers, Laura J. Megeath, Jolanta Górska-Andrzejak, Ian A. Meinertzhagen, Thomas L. Schwarz "Axonal Transport of Mitochondria to Synapses Depends on Milton, a Novel Drosophila Protein" ''Nature'' Volume 36, Issue 6, p1063–1077, 19 December 2002. According to Google ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Connectome
A ''Drosophila'' connectome is a list of neurons in the ''Drosophila melanogaster'' (fruit fly) nervous system, and the chemical synapses between them. The fly's central nervous system consists of the brain plus the ventral nerve cord, and both are known to differ considerably between male and female. Dense connectomes have been completed for the female adult brain, the male and female nerve cords, and the female larval stage. The available connectomes show only chemical synapses - other forms of inter-neuron communication such as gap junctions or neuromodulators are not represented. ''Drosophila'' is the most complex creature with a connectome, which had only been previously obtained for three other simpler organisms, first '' C. elegans''. The connectomes have been obtained by the methods of neural circuit reconstruction, which over the course of many years worked up through various subsets of the fly brain to current efforts aimed at a unified central brain and VNC connectome, fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Anatomy
Insect morphology is the study and description of the physical form of insects. The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. Three physical features separate insects from other arthropods: they have a body divided into three regions (called tagmata) (head, thorax, and abdomen), three pairs of legs, and mouthparts located ''outside'' of the head capsule. This position of the mouthparts divides them from their closest relatives, the non-insect hexapods, which include Protura, Diplura, and Collembola. There is enormous variation in body structure amongst insect species. Individuals can range from 0.3 mm ( fairyflies) to 30 cm across ( great owlet moth); have no eyes or many; well-developed wings or none; and legs modified for running, jumping, swimming, or even digging. These modifications allow insects to occupy almost every ecological niche except the deep ocean. This article describe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
