Hostname: page-component-76fb5796d-22dnz Total loading time: 0 Render date: 2024-04-26T16:22:02.499Z Has data issue: false hasContentIssue false
  • English
  • Français

Loss of Consciousness is Associated with Elevated Cognitive Intra-Individual Variability Following Sports-Related Concussion

Published online by Cambridge University Press:  10 August 2020

Victoria C. Merritt Open the ORCID record for Victoria C. Merritt [Opens in a new window] ,
Liora S. Greenberg ,
Jessica E. Meyer  and
Peter A. Arnett Open the ORCID record for Peter A. Arnett [Opens in a new window]
Victoria C. Merritt*
Affiliation:
VA San Diego Healthcare System, San Diego, CA, USA
Liora S. Greenberg
Affiliation:
The Pennsylvania State University, University Park, PA, USA
Jessica E. Meyer
Affiliation:
University Hospitals Cleveland Medical Center, Cleveland, OH, USA
Peter A. Arnett
Affiliation:
The Pennsylvania State University, University Park, PA, USA
*
*Correspondence and reprint requests to: Victoria C. Merritt, Ph.D., VA San Diego Healthcare System (151B), 3350 La Jolla Village Drive, San Diego, CA92161, USA. Tel: +1 858-558-8585x2670; Fax: +1 858-642-6340. E-mail: victoria.merritt@va.gov
Get access Rights & Permissions [Opens in a new window]

Abstract

Objective:

The purpose of this study was to evaluate whether loss of consciousness (LOC), retrograde amnesia (RA), and anterograde amnesia (AA) independently influence a particular aspect of post-concussion cognitive functioning—across-test intra-individual variability (IIV), or cognitive dispersion.

Method:

Concussed athletes (N = 111) were evaluated, on average, 6.04 days post-injury (SD = 5.90; Mdn = 4 days; Range = 1–26 days) via clinical interview and neuropsychological assessment. Primary outcomes of interest included two measures of IIV—an intra-individual standard deviation (ISD) score and a maximum discrepancy (MD) score—computed from 18 norm-referenced variables.

Results:

Analyses of covariance (ANCOVAs) adjusting for time since injury and sex revealed a significant effect of LOC on the ISD (p = .018, ηp2 = .051) and MD (p = .034, ηp2 = .041) scores, such that athletes with LOC displayed significantly greater IIV than athletes without LOC. In contrast, measures of IIV did not significantly differ between athletes who did and did not experience RA or AA (all p > .05).

Conclusions:

LOC, but not RA or AA, was associated with greater variability, or inconsistencies, in cognitive performance acutely following concussion. Though future studies are needed to verify the clinical significance of these findings, our results suggest that LOC may contribute to post-concussion cognitive dysfunction and may be a risk factor for less efficient cognitive functioning.

Keywords

Injury severity characteristicsCognitionDispersionIIVSports concussionCollege athletes
Type
Brief Communication
Information
Journal of the International Neuropsychological Society , Volume 27 , Issue 2 , February 2021 , pp. 197 - 203
Copyright
Copyright © INS. Published by Cambridge University Press, 2020

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bangen, K.J., Weigand, A.J., Thomas, K.R., Delano-Wood, L., Clark, L.R., Eppig, J., … Bondi, M.W. (2019). Cognitive dispersion is a sensitive marker for early neurodegenerative changes and functional decline in nondemented older adults. Neuropsychology, 33(5), 599–608.CrossRefGoogle ScholarPubMed
Collins, M.W., Iverson, G.L., Lovell, M.R., McKeag, D.B., Norwig, J., & Maroon, J. (2003). On-field predictors of neuropsychological and symptom deficit following sports-related concussion. Clinical Journal of Sport Medicine, 13(4), 222–229.CrossRefGoogle ScholarPubMed
Costa, A.S., Dogan, I., Schulz, J.B., & Reetz, K. (2019). Going beyond the mean: intraindividual variability of cognitive performance in prodromal and early neurodegenerative disorders. The Clinical Neuropsychologist, 33(2), 369–389.CrossRefGoogle ScholarPubMed
Dougan, B.K., Horswill, M.S., & Geffen, G.M. (2014). Do injury characteristics predict the severity of acute neuropsychological deficits following sports-related concussion? A meta-analysis. Journal of the International Neuropsychological Society, 20(1), 81–87.CrossRefGoogle ScholarPubMed
Gleason, C.E., Norton, D., Anderson, E.D., Wahoske, M., Washington, D.T., Umucu, E., … Carlsson, C.M. (2018). Cognitive variability predicts incident Alzheimer’s disease and mild cognitive impairment comparable to a cerebrospinal fluid biomarker. Journal of Alzheimer’s Disease, 61(1), 79–89.CrossRefGoogle ScholarPubMed
Harmon, K.G., Clugston, J.R., Dec, K., Hainline, B., Herring, S., Kane, S.F., … Poddar, S.K. (2019). American medical society for sports medicine position statement on concussion in sport. British Journal of Sports Medicine, 53(4), 213–225.CrossRefGoogle Scholar
Hilborn, J. V, Strauss, E., Hultsch, D.F., & Hunter, M.A. (2009). Intraindividual variability across cognitive domains: investigation of dispersion levels and performance profiles in older adults. Journal of Clinical and Experimental Neuropsychology, 31(4), 412–424.CrossRefGoogle ScholarPubMed
Holtzer, R., Verghese, J., Wang, C., Hall, C.B., & Lipton, R.B. (2008). Within-person across-neuropsychological test variability and incident dementia. JAMA, 300(7), 823–830.CrossRefGoogle ScholarPubMed
Hultsch, D.F., MacDonald, S.W., & Dixon, R.A. (2002). Variability in reaction time performance of younger and older adults. Journal of Gerontology: Psychological Sciences, 57(2), P101–P115.CrossRefGoogle ScholarPubMed
Iverson, G.L., Gardner, A.J., Terry, D.P., Ponsford, J.L., Sills, A.K., Broshek, D.K., & Solomon, G.S. (2017). Predictors of clinical recovery from concussion: a systematic review. British Journal of Sports Medicine, 51(12), 941–948.CrossRefGoogle ScholarPubMed
Jones, J.D., Kuhn, T., Mahmood, Z., Singer, E.J., Hinkin, C.H., & Thames, A.D. (2018). Longitudinal intra-individual variability in neuropsychological performance relates to white matter changes in HIV. Neuropsychology, 32(2), 206.CrossRefGoogle ScholarPubMed
Lovell, M.R. (2016). ImPACT: Administration and Technical Manual. ImPACT Applications, Inc.Google Scholar
MacDonald, S.W., Li, S.-C., & Bäckman, L. (2009). Neural underpinnings of within-person variability in cognitive functioning. Psychology and Aging, 24(4), 792.CrossRefGoogle ScholarPubMed
McCrory, P., Feddermann-Demont, N., Dvorak, J., Cassidy, D., McIntosh, A., Vos, P.E., … Tarnutzer, A.A. (2017). What is the definition of sports-related concussion: a systematic review. British Journal of Sports Medicine, 51, 877–887.CrossRefGoogle ScholarPubMed
McCrory, P., Meeuwisse, W., Dvorak, J., Aubry, M., Bailes, J., Broglio, S., … Castellani, R.J. (2018). Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016. British Journal of Sports Medicine, 51, 838–847. doi: 10.1136/bjsports-2017-097699 Google Scholar
Merritt, V.C., Greenberg, L.S., Guty, E., Bradson, M.L., Rabinowitz, A.R., & Arnett, P.A. (2019). Beyond measures of central tendency: novel methods to examine sex differences in neuropsychological performance following sports-related concussion in collegiate athletes. Journal of the International Neuropsychological Society, 25(10), 1094–1100.CrossRefGoogle ScholarPubMed
Merritt, V.C., Meyer, J.E., Cadden, M.H., Roman, C.A., Ukueberuwa, D.M., Shapiro, M.D., & Arnett, P.A. (2017). Normative data for a comprehensive neuropsychological test battery used in the assessment of sports-related concussion. Archives of Clinical Neuropsychology, 32(2), 168–183.Google ScholarPubMed
Rabinowitz, A.R., & Arnett, P.A. (2013). Intraindividual cognitive variability before and after sports-related concussion. Neuropsychology, 27(4), 481–490.CrossRefGoogle ScholarPubMed
Teel, E.F., Marshall, S.W., Shankar, V., McCrea, M., & Guskiewicz, K.M. (2017). Predicting recovery patterns after sport-related concussion. Journal of Athletic Training, 52(3), 288–298.CrossRefGoogle ScholarPubMed
Troyer, A.K., Vandermorris, S., & Murphy, K.J. (2016). Intraindividual variability in performance on associative memory tasks is elevated in amnestic mild cognitive impairment. Neuropsychologia, 90, 110–116.CrossRefGoogle ScholarPubMed
Vandermorris, S., & Tan, J.E. (2015). Intraindividual Variability and Neuropsychological Functioning Across the Adult Lifespan. New York: Routledge.Google Scholar