Relation between subjective fogginess and neuropsychological testing following concussion

J Int Neuropsychol Soc. 2004 Nov;


Iverson, G. L., M. Gaetz, M. R. Lovell and M. W. Collins.



The purpose of this study was to examine the relation between feeling foggy at 1-week postconcussion and neuropsychological outcome. The outcome variables were derived from a computerized neuropsychological screening battery (ImPACT). Participants were 110 high school students who sustained a 770 Abstracts / Archives of Clinical Neuropsychology 17 (2002) 715–867 sports-related concussion and were evaluated 5–10 days postinjury (mean = 6.8 days). The average age of the sample was 15.9 years (S.D. = 1.2), and 84.5% were male. The breakdown of athletes by sport was as follows: football (63.6%), basketball (12.7%), soccer (11.8%), hockey (3.6%), and other (8.3%). Athletes were divided into two groups on the basis of self-reported fogginess. The first group reported no fogginess (n = 91), whereas the second group reported experiencing some degree of fogginess (n = 9) on a 6-point scale. The athletes with persistent fogginess experienced a large number of other postconcussion symptoms, compared to the athletes with no fogginess (P <.0001; d = 3.44, very large effect size). In addition, the athletes with persistent fogginess had significantly slower reaction times) (P <.0002; d = 1.0, large effect), reduced memory performance (P < .01; d = 0.97, large effect), and slower processing speed (P <..004; d = 0.79, large effect). Thus, athletes with any degree of self-reported fogginess at 1-week postinjury are likely to have persistent adverse effects from their concussions in multiple domains. Therefore, high school athletes with postinjury fogginess, regardless of severity, will likely benefit from an extended break from participation

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