A neural model of the interaction of tectal columns in prey-catching behavior

Abstract

Building on a simple model of a tectal column as the unit of processing in the amphibian tectum, we conduct a computer analysis of the interaction of a linear array of such columns. The model suggests that the inhibitory and excitatory activity in the tectum may have three functions: 1) spatio-temporal facilitation of column activity to a moving stimulus; 2) preference for the head of the stimulus, probably to avoid possible defensive reactions of the prey; and 3) modulating the state of excitation of the column once it has produced a response. The model also shows that the spatio-temporal effects of excitation and inhibition increases the acuity of the animal to the direction of the prey, through processes similar to lateral inhibition.

Saccadic Interception of a Moving Visual Target after a Spatiotemporal Perturbation

“…Two, the microstimulation could interfere with signals encoding the expected target location. Indeed, if target motion signals from frontal eye field (Barborica and Ferrera, 2003;Cassanello et al, 2008;Ferrera and Barborica, 2010) or medial superior temporal (MST) area (Maioli et al, 1992) influence the population activity in the dSC for encoding the expected target location (Witten et al, 2006), microstimulation could affect either a propagation of activity in the dSC (Arbib and Lara, 1982) or the recruitment of additional neurons that would burst before the interceptive saccade is launched toward the target (for the remapping hypothesis, see Fleuriet et al, 2011).…”

Neuroethological Analysis of the Innate Releasing Mechanism for Prey-Catching Behavior in Toads

“…According to symmetrical coupling this phenomenon is largely independent of the stimulus movement direction in the x-y coordinates. These properties can be explained by a special columnar organization of the anuran tectum (Fig.21C) (Szekely and Lazar, 1976;Arbib and Lara, 1981). They are expressed in the intact animal by (i) worm preference and its invariance with regard to stimulus velocity and direction of movement, (ii) spatio temporal summation by double stimulation, (iii) "attention" (Ingle, 1975) and"memory" phenomena (GrUsser andGrUsser-Cornehls, 1970) of some tectal neurons.…”

“…According to Golgi studies at least 6 types of neuron can be distinguished anatomically (Szekely and Lazar, 1976); of these the pyramidal cells and ganglionic cells mediate the main output of the tectum with their axons coursing in layer 7 (Fig.21B). It is assumed that assemblies of tectal neurons are organized in columns oriented vertically to the tectal surface ( Fig.21C) (Szekely and Lazar, 1976;Arbib and Ewert, 1971). .…”

SLONN: A Simulation Language for modeling of Neural Networks

“…One is on the side of computational neuroscience: neural networks which are carefully constructed to be consistent with neurobiological data are used to form theories of neural structures responsible for certain animal behaviors. For example, much work has been done on visuomotor mechanisms of toad and frog by neural modeling (Arbib and Lara, 1982;Cervantes, et al, 1985). Another is on the side of neural computing: a single neuron is viewed as a computing unit which can be connected to and work in parallel with other units so as to solve certain problems.…”