An experiment has been carried out to show that extrinsic silicon injection-mode infrared detectors can be used to simulate the transient response of neurons in biological vision systems. The neural response provides a means of high pass filtering in vision system focal plane parallel processing. The high pass filtering emphasizes transients in images. Possible IR imaging applications include surveillance, motion sensing, and tracking. The IR detector output pulses are sufficiently large that amplification is not required. This could facilitate parallel processing in or near the focal plane. The IR transient sensing approach is quantitatively analyzed in terms of a model for the detector and the associated circuitry. Excellent agreement is found between the model and the experimental data.