Some confusion[6][lower-alpha 1] is caused by the fact that an American school of linguistics of 1910s through 1950s, which was based on structural psychology, (especially Wilhelm Wundt's Völkerpsychologie); and later on behavioural psychology,[7][lower-alpha 2] was nicknamed 'American structuralism'.[8] This framework was not structuralist in the Saussurean sense that it did not consider language as arising from the interaction of meaning and expression.