Effects of the common cold on mood and performance

Previous research has shown that both experimentally-induced and naturally occurring upper respiratory tract illnesses (URTIs) influence mood and ment al functioning. None of the previous studies of naturally occurring colds h as conducted appropriate virological assays to determine the nature of the infecting agent. This is an essential methodological step in studies of mal aise associated with URTIs. The aim of this research was to investigate the effects of naturally occurring colds on mood and objective measures of per formance. This was done by first conducting a cross-sectional comparison of 37 healthy people and 158 volunteers with colds and then a longitudinal st udy in which 100 volunteers developed colds and 87 remained healthy. Virolo gical techniques were used to identify infecting agents and comparisons mad e across the different groups. The results showed that having a cold was as sociated with reduced alertness and slowed reaction times. These effects we re observed both for colds where the infecting virus was identified and tho se where it was not. Similar effects were obtained for both rhinovirus and coronavirus colds. One may conclude that upper respiratory tract illnesses lead to a reduction in subjective alertness and impaired psychomotor functi oning. This was true for both illnesses where the infecting agent was ident ified and for those clinical illnesses where no virus was detected. It is n ow important to identify the mechanisms linking infection and illness with the behavioural changes. Similarly, the impact of these effects on real-lif e activities such as driving needs examining. Finally, methods of treatment need to be developed which not only treat the local symptoms of the illnes ses but remove the negative mood and the performance impairments. (C) 1998 Elsevier Science Ltd. All rights reserved.