Anatomical organization of retinotopic motion‐sensitive pathways in the optic lobes of flies

Abstract

Anatomical methods have identified conserved neuronal morphologies and synaptic relationships among small-field retinotopic neurons in insect optic lobes. These conserved cell shapes occur across many species of dipteran insects and are also shared by Lepidoptera and Hymenoptera. The suggestion that such conserved neurons should participate in motion computing circuits finds support from intracellular recordings as well as older studies that used radioactive deoxyglucose labeling to reveal strata with motion-specific activity in an achromatic neuropil called the lobula plate. While intracellular recordings provide detailed information about the motion-sensitive or motion-selective responses of identified neurons, a full understanding of how arrangements of identified neurons compute and integrate information about visual motion will come from a multidisciplinary approach that includes morphological circuit analysis, the use of genetic mutants that exhibit specific deficits in motion processing, and biomimetic models. The latter must be based on the organization and connections of real neurons, yet provide output properties similar to those of more traditional theoretical models based on behavioral observations that date from the 1950s. Microsc. Res. Tech. 62:132-150, 2003.

Humanitarian Demining Using an Insect Based Chemical Unmanned Aerial Vehicle

“…These 2 simple operations render the system more robust to changes in illumination (Dubs 1982). At the level of the Medulla we find the first visual motion sensitive neurons (Borst & Egelhaaf 1993;Douglass & Strausfeld 2003). Since the 60s, when Reichardt first proposed the, so called, correlation model, insects are believed to possess neurons that are capable to compute local directional motion, the Elementary Motion Detectors (EMD), and that they use this information for navigation purposes (Reichardt 1961) (Fig.…”

“…Generally in insects, about two thirds of their brain is dedicated to visual processing to support navigation (Strausfeld 1976). Visual processing is mainly done by feed-forward neural structures dedicated to extract wide filed directional optic flow that is believed to be used for flight control (Hausen 1982a;Hausen 1982b;Egelhaaf & Borst 1993a;Krapp et al 1998;Franz & Krapp 2000;Douglass & Strausfeld 2003;Higgins et al 2004). In later processing stages, this information is integrated and used for landing, course and altitude control and collision avoidance (Rowel 1971;David 1982;Rind & Simmons 1992;Egelhaaf & Borst 1993b;Srinivasan et al 1996;Srinivasan et al 2000;Tammero & Dickinson 2002;Higgins et al 2004).…”

A single-cell level and connectome-derived computational model of the Drosophila brain

“…Although each image has been transformed (or warped) and registered in a standard brain space, this process inevitably created warping error. Ideally, the probability of synapse formation between two neurons is correlated with the degree of contact between them (Douglass and Strausfeld 2003;Tanaka, Endo, and Ito 2012;Peters and Payne 1993). However, due to the warping error, if two neurons have closely contacted branches in the standard brain space, this does not necessarily indicate that they form synapses.…”

Elementary Motion Detection

“…Therefore, there exist two different pathways involved in motion computation, starting with L1 and L2, respectively. Both pathways merge again in the lobula plate where T4 and T5 innervate the so-called lobula plate tangential cells (Bausenwein and Fischbach, 1992;Douglass and Strausfeld, 2003;Fischbach and Dittrich, 1989). The latter cells are directionally selective and involved in the visual course control of the fly (Borst and Haag, 2002;Borst et al, 2010).…”

“…T5 cells are assumed to be crucial for motion vision (Douglass and Strausfeld, 1995). They project to distinct layers of the lobula plate containing cells selective for motion Douglass and Strausfeld, 1995;Douglass and Strausfeld, 2003;Strausfeld, 1976). …”