There had been precursors to these cognitive psychology pioneers. Specifically, Heman Ebbinghaus in the late 19th century had done research that is a more direct link to these people in the 1950s than the behaviorists. Ebbinghaus used nonsense syllables to study memory in a quantifiable manner. Nonsense syllables are CVCs, consonent- vowel-consonent trigrams. Ebbinghaus chose those as his subject matter, because he wanted to study memory in a pure form. Hence, he did not want to use items that already had some meaning attached to them. Ebbinghaus demonstrated effects of interference, practice time and forgetting.