Fig. 20 A behavioral ocular motor system model capable of simulating normal and abnormal ocular motor responses to various target stimuli. Major sensory and motor signal pathways are shown by thick lines, whereas logic and function-control signal pathways are shown by thin lines. Abbreviations as in Figure 19 in addition to: TI, tonic imbalance; Sacc, saccade; FS, foveating saccade; BS, braking saccade; AL, Alexander's law; TIAL, tonic imbalance modified by Alexander's law; Pos, position; Vel, velocity; E', reconstructed eye position; Tvel', reconstructed target velocity; Evel', reconstructed eye velocity; OMN, ocular motor neuron; EOM, extraocular muscle; k, constant.