The Effects of Redundancy and Familiarity on Translating and Repeating Back a Foreign and a Native Language

The experiment explored the effect of sequential constraints on two speech transmission tasks: ( a ) ‘shadowing’ or repeating back passages in a native and in a foreign language; ( b ) simultaneous translation between a foreign and a native language. Three factors affecting performance were revealed: (1) efficiency decreased in both tasks with increased information rate in the presentation of the passages; (2) the familiarity of the language affected subjects' performance in shadowing; this effect was independent of sequential constraints; (3) translation proved more difficult than shadowing, but in this case the decrement was greater the higher the information content of the passages. This suggested (i) that sequential constraints are important in facilitating both types of speech transmission; (ii) that they are learnt concurrently with vocabulary in the acquisition of a foreign language; (iii) that translating is more difficult than shadowing not only because of decreased familiarity of either input or output, but also because of the increased decision load imposed by the more complex transformation between input and output. The roles of grammatical and semantic constraints were separated by the use of passages with words chosen at random but syntax conforming to normal rules. Performance with these passages was intermediate between that with normal prose and that with random words; the grammatical constraints seemed relatively more important than constraints of meaning in shadowing than in translating, in a native than in a foreign language, and in French than in English. The ear‐voice span was measured for six subjects and was found to be greater for translating than for shadowing, but to be unaffected by the degree of sequential constraints.