Morse code signals were presented dichotically to Morse code operators and to naive subjects with no knowledge of Morse code. The operators showed right ear superiority, indicating left hemisphere dominance for the perception of dichotically presented Morse code letters. Naive subjects showed the same right ear superiority when presented with a set of dot-dash patterns restricted to pairs of seven or fewer elements, counting dots and dashes each as elements. When presented with longer stimuli, naive subjects showed left ear superiority, indicating right hemisphere dominance, the opposite of their result with the shorter stimuli. This seems to indicate that pairs consisting of seven or fewer elements are perceived with reference to the subparts of which they are composed, but that longer stimuli force naive subjects to adopt strategies involving the holistic qualities of the stimuli. It would seem, therefore, that the left hemisphere is specialized for processing the sequential parts of which a stimulus is composed. This research, in conjunction with other work on the topic, suggests that language is lateralized to the left hemisphere because of its dependence on segmental subparts, and that this dependence characterizes language perception as distinct from most other human perception. (Author/TL)