The CANS-MCI for Concussion Assessment

The early detection of cognitive ability changes due to sports concussion is critical because of the increased vulnerability that follows a concussion.

According to Harmon et al, “Animal and human studies support the concept of post-concussive vulnerability, showing that a second blow before the brain has recovered results in worsening metabolic changes within the cell. Experimental evidence suggests the concussed brain is less responsive to usual neural activation, and when premature cognitive or physical activity occurs before full recovery the brain may be vulnerable to prolonged dysfunction.”^[1] This extensive review concludes that recognition and initial assessment of concussion should be guided by a symptom checklist, cognitive evaluation (including orientation, past and immediate memory, new learning, and concentration), balance tests, and further neurologic physical examination. Others agree that the dimensions central to computerized cognitive tests of cognitive ability changes related to concussion are memory, cognitive processing speed, and reaction time.^[2,3]

The most neglected but critical aspect of sports-related cognitive ability testing is the bias of testers. Assessment must take place with complete and guaranteed neutrality. Coaches, trainers, and even sports team physicians should not be expected to be objective. The Computer-Administered Neuropsychological Screen for Mild Cognitive Impairments (CANS-MCI) test battery is the only one capable of secure objective neutrality. The creation of test reports by qualified, independent test analysts, the comprehensiveness of testing, the longitudinal comparison against pre-concussion baseline measurement, and the detection of attempts to look bad on baseline testing are all handled more effectively by the CANS-MCI than by any other testing procedure. The CANS-MCI baseline is examined by independent professionals for the presence of errors people almost only make when they are trying to look bad. These errors are otherwise actually very rare.

The CANS-MCI is entirely self-administered. After entry of the identity code for a player, the person responsible for testing leaves the room. The CANS-MCI is the only test battery that does not require the presence, much less training, of a test administrator. When the tests are complete, the data may be automatically sent to a central server where they are kept for comparison. Scoring and longitudinal comparison test analysis is performed by an independent neuropsychology technician who does not know the person tested. Test reports compare post-events or end-of-season tests against baseline.

The CANS-MCI tests were designed to measure attentional speed and flexibility; executive mental control; immediate memory; and delayed recall. In order to measure only these dimensions, most often impaired when there has been a traumatic head injury (TBI), the CANS-MCI Short Form is used. By eliminating the dementia-detecting symbol and fluency tests contained in the Long Form, a significant savings in time is gained along with a sharper focus upon concussion-related changes. Problems with verbal initiation and planning, which can be caused by damage to the front of the brain1 are still detected by the executive control tests.

The concussion-assessment version of the CANS-MCI is designed for use by adults (age 16-60). It is sensitive to patterns of test responding that appear when a person, usually on a baseline test for sports, is trying to look bad. Baseline tests, software and confidential data storage are free.

The risk factor questions can be adjusted for each purpose, according to the age and context relevant to a facility. For example, a 10-question depression scale is often included in the concussion Form. To examine the CANS-MCI without a touch screen and without collecting data, go to our CANS-MCI Demonstration Versions.

The cognitive domains measured on the CANS-MCI Short Form

Attention speed: Executive functioning Factor

The dimension of visual scanning speed, central to our Orientation process and the traditional Trail Making A test, is also central to our Picture Matching^[5] and Design Matching^[6] brief executive function tests.

Attentional Flexibility: Executive Functioning Factor

The dimension of attentional flexibility is central to our Design Matching^[6] and Stroop^[7] tests.
Reliability is enhanced by combining scores into an Executive Function factor score based upon a larger sample of subjects and incorporation of independent full neuropsychological evaluation comparisons.

Memory for new learning^[8]

• Significant correlations with the Weschler Memory Scale were published in Tornatore et al (2005).^[9]
• Correlation between the Memory factor score with the Learning Efficiency and Delayed Verbal Recall scores on the Rey Auditory Verbal Learning Test (R-AVLT also indicate a high level of sensitivity to the most critical dimensions of memory impairment.

CANS-MCI longitudinal comparisons between test sessions can be performed frequently because alternative correct items are presented automatically each time a person returns for re-testing. Both the reliability and the usability of the CANS-MCI are unique. The exceptional user friendliness of the CANS-MCI in both English and Spanish has been documented in reviews of all computerized cognitive function testing.^[10]

Footnotes

1. Harmon, KG, Drezner, J, Gammons, M et al. American Medical Society for Sports Medicine Position Statement: Concussion in Sport, Clin J Sport Med 2013;23:1–18.

2. Ellemberg D, Henry LC, Macciocchi SN, et al. Advances in sport concussion assessment: from behavioral to brain imaging measures.  J Neurotrauma. 2009;26:2365–2382.

3. Randolph C, McCrea M, Barr WB. Is neuropsychological testing useful in the management of sport-related concussion? J Athl Train. 2005;40: 139–152.

4. Wood, R. Ll., & McMillan. (2001). Neurobehavioural Disability and Social Handicap Following Traumatic Brain Injury. East Sussex, England: Psychology Press.

5. Word-to-Picture Matching (Executive function factor – verbal information processing speed):  This is a matching cognition test in which four pictures of objects are presented along with one word, and the person is instructed to touch the picture that goes with the word.  Accuracy and reaction times for 14 trials are measured.

6. Design Matching: (Executive Function factor – visual information processing speed, and spatial memory):  Eight designs are matched with letters.  The letters are not in order. A set of alphabetically arranged letter buttons appears.  Designs are presented one at a time and replaced when any button is touched.  The complexity of attention switching required is increased by within-test interference.  This test lasts for 70 seconds.

7. Stroop: (Executive Function factor – Mental Control): After guided practice, 12 concordant (word and ink color matched) and 24 discordant (word and ink color mismatched) words are presented.  The average latency for the correct discordant items is precisely measured with this self-administered test for dementia.

8. Free and Guided Recall, Immediate and Delayed (Memory Factor):  This memory loss screening test involves the acquisition of memory for the names of objects and guides the strategy subjects are likely to use to remember them toward a common strategy (association with an object category).  Five sets of four pictures are presented along with one category for each picture. This test presents the four pictures as four quadrants in a manner that is identical to the previous test, eliminating the distraction that novelty creates on memory tests.  Then a test is presented that contains the four correct objects and incorrect items from the same four categories.  Any incorrect responses result in a second presentation of the set of four pictures.  Five sets of four pictures are presented in this fashion.  After all five acquisition sets, a free recognition test trial is presented.  This is a series of 20 three-button presentations, one correct button and two incorrect from categories other than the correct one.  If any of the 20 correct items are not touched, the person receives a cued recall re-test on that item, consisting of three buttons, the missed item along with two other items in that same category.  After each of the cued recall tests, the items that were not correctly touched on the free recall test are shown again with category prompts for re-acquisition.  One delayed free recall trial is given.  If any of the 20 correct items are not touched, the subject receives a cued recall test on that item (the missed item along with two other items in that same category).

9. Tornatore, JB, Emory Hill, E, Jo Anne Laboff, J, and Mary E. McGann, ME   Self-Administered Screening for Mild Cognitive Impairment: Validation of a Computerized Test Battery.   Journal of Neuropsychiatry and Clinical Neurosciences, Volume 17, No. 1, 98-105, 2005.

10. Wild, K, Howieson, D, Webbe,F, Seelye, A, Kaye, J.  Status of computerized cognitive testing in aging: A systematic review.  Alzheimer’s & Dementia, 4 (6), 428-437, 2008.