Behavioral or hemispheric asymmetry: is there a default option?

The presence of acuity gradients as a moderating variable in hemifield research is not in question. Their importance as a determinant of hemifield differences is unclear, however. The major issues are as follows. First, do vertical displays provide an appropriate control for the acuity gradient? Second, do the initial letters of a word play a critical role in word recognition, either in information-theoretic terms or because the lexicon is itself organized around access codes based on the initial letter or letters of words? Third, do behavioral and hemispheric accounts provide equally attractive explanations of Task Level X Visual Field interactions? Fourth, if the two accounts are equally attractive on empirical grounds, which is to be preferred? Each of these issues is addressed in this reply to M. P. Bryden's (1986, Brain and Cognition, 5, 362-368) and J. Hellige's (1986, Brain and Cognition, 5, 369-376) comments on our article (K. Kirsner & S. Schwartz 1986, Brain and Cognition, 5, 354-361).