Preprocessing is not the same as interpretation, in the same way that a pixel shader is not computer vision.
Everything is quite fuzzy in the brain... The eye already does basic pattern recognition (stripes, contrasts, rings).
One could argue that that is already part of the character detection/interpretation process.
it does involve energy though, which was the original premis. Now whether total number of joules consumed over <> vs != vs ≠ is the real debate and gonna be hard to study I think...