A computational model of stereoscopic prey capture in praying mantises
Fig 2
Schematic diagram of the disparity energy model.
The model postulates a binocular neuron which receives input from each eye, representing the inner product of the retinal image with a receptive field function. The receptive field function represents the effect of stimulation at each point in the retinal image on the binocular neuron, and can be thought of as an effective synaptic weight (though the real pathway is multisynaptic). Red and blue are used to represent inhibitory and excitatory weights respectively. The activity of the neuron is then represented as a nonlinear function of its total input. In the original energy model [24], this nonlinearity was a threshold at 0 followed by squaring; we generalise the model to allow for a non-zero threshold −b and arbitrary exponent γ. Mathematical symbols are defined below, Eqs (1) and (2). We postulate that this binocular neuron synapses onto a motoneuron in such a way that the instantaneous strike probability is proportional to the activity of the binocular neuron.