I am looking for information on how to set up a letter flanker with two conditions (noise heterogeneous-similar, noise heterogeneous-dissimilar, following Eriksen & Eriksen's (1974) terminology). Specifically:
- is it permissible to deviate in the choice of noise letters from the ones presented in Eriksen & Eriksen's study (N/W/Z) & (G/J/Q), provided they present the same structural properties according to the Gibson system (1969)?
- can the order of the noise letters be randomized or do they have to follow a specific predetermined order?
Thanks!