The ‘Distraction Effect’ and Information Processing Complexity

It was found earlier that a transient ‘distraction effect’ was apparent when 80 dB noise bursts occurred at random during an on-going serial-response task. Experiments are now reported in which the information processing ‘load’ of the on-going serial task was varied (a) by the introduction of increased stimulus predictability, or (b) by the introduction of stimulus–response incompatibility. On the notion that the information processing system acts as a single channel, with increased stimulus predictability there should be a reduced distraction effect, because there would be more capacity available for responding to noise bursts whilst maintaining serial task performance; the reverse should be true for the case of increased stimulus–response incompatibility. Results suggested that the ‘distraction effect’ was reduced in both cases. An additional explanation suggesting that the information processing load of the task itself determined whether or not the noise bursts were providing effective rivalry with the task signals is considered.