Is perceived length affected by interactions between orientation detectors?

Illusions of length are known to occur with simple geometric stimuli or shapes related to the constancies of the perceived world. In this experiment illusions of length are also found to occur with complex randomly orientated shapes, unrelated to any constancy structure within the perceived environment. These results also indicate that some length illusions are directly related to the encoding of orientation as some perceived vertical to horizontal extent; and that the magnitude of the illusion may be predicted from known interactions between orientation detectors within the human visual system.