Selective Auditory - Visual Interference Effects in a Dual Task Paradigm: Implications for Assessing Individual Differences

Three experiments are reported that tested predictions from a multiple resource framework for selective patterns of interference in a visual - auditory dual task paradigm. Subjects performed an auditory memory search task both alone and in conjunction with several visual information processing tasks. In Experiment 1 the level of speech intelligibility in the memory search task did not affect performance in an unstable tracking task. In Experiments 2 and 3 speech intelligibility did affect performance in a spatial processing task and a mathematical reasoning task. These results are discussed in terms of their relevance for designing a test battery to identify individuals likely to be affected by changes in speech intelligibility.