THE EFFECTS OF NOISE AND DOUBLING THE SIGNAL FREQUENCY ON INDIVIDUAL DIFFERENCES IN VISUAL VIGILANCE PERFORMANCE

• Published in: The British journal of psychology 1966-11, Vol.57 (3-4), p.381-389
• Main Authors: DAVIES, D. R., HOCKEY, G. R. J.
• Format: Article
• Language: English
• ISSN: 0007-1269; 2044-8295
• DOI: 10.1111/j.2044-8295.1966.tb01039.x

Four groups of 6 extraverts and 4 groups of 6 introverts, selected by the Maudsley Personality Inventory, performed a 32 min visual cancellation task under one of two conditions of signal frequency, high and low, and in either noise (95 db) or quiet (70 db). In quiet, at both levels of signal frequency, extraverts showed a steady decline in the number of signals detected correctly but introverts did not. Neither group showed a decrement under noise conditions. Noise, compared with quiet, significantly increased the number of correct detections made by extraverts under low signal frequency conditions but a similar increase under high signal frequency conditions was not significant. The addition of noise had no significant effect on the number of correct detections made by introverts. Doubling the signal frequency had no significant effect on the performance of introverts or extraverts in either noise or quiet. Introverts made significantly more errors of commission in quiet than in noise while extraverts made significantly more in noise than in quiet. Possible reasons for the findings are discussed.