Cognitive effects of passive smoking

The cognitive performance of 32 non-smoking subjects was tested on two separate occasions. In one condition subjects performed on a modified Wilkinson auditory detection task and attempted a modified Raven's progressive matrices test whilst sitting in a room with a confederate who was smoking cigarettes. In the second, non-smoky, condition the subjects undertook parallel forms of the two tests but were in a clean environment with the same confederate who did not smoke. The results indicated a significant reduction in performance on both tests in the smoky over the non-smoky condition. Furthermore, the data from the detection task indicated that the confederate had a significant influence on the level of this reduction. Implications of these results are discussed, particularly with respect to the roles of carbon monoxide and of social variables in mediating the performance reduction.