1.   At the next stage - abstract letter detection - all twenty-six letters of the alphabet are represented by individual letter detectors.

2.   Every feature detector in the feature-detection stage is linked to every letter detector in the letter-detector stage.

3.   The letter detectors in turn excite detectors for consistent words.

4.   These experiments provide strong evidence for the existence of a system of abstract letter detectors.

5.   This letter detector remains active for some brief period of time, until the pattern mask is presented.