Military officers

Mild traumatic brain injuries cause substantial cognitive problems in military officers. A basic laboratory experiment conducted by Boston University and the ""Veterans Affairs Boston Healthcare System (VABHS)"" indicated that military commanders exposed to blast frequently experience long-term brain tissue damage as well as ""chronic traumatic encephalopathy (CTE)."" Although some of these findings provide an excellent chance for researchers to conduct various tests to ascertain the long-term cognitive performance of deployed military personnel following concussion damage, relatively few studies provide an adequate assessment of such conditions. The few different articles examined on focus on the existence of a relationship between concussion injury and individuals' cognition without testing the effect or the extent of such an association. First, this research proposes a strong positive relationship between concussion damage and soldiers' cognition. Secondly, the paper proposes the use of n-Back test and PVSAT to assess the effect of concussion sustained during a military deployment on soldier's cognition.

A Proposal to Design and Validate a New Test to Assess the Effect of Concussion Sustained during a Military Deployment on Soldiers' Cognition

Introduction

Even though only a few military officers report severe cognitive challenges after experiencing mild traumatic brain injuries, behavioural testing studies give consistent results on the effect of concussion sustained during a military deployment on soldiers' cognition (Ropper, & Gorson, 2007). For instance, blasts investigators from Boston University and the "Veterans Affairs Boston Healthcare System (VABHS)" in a simple laboratory experiment demonstrated that military officers exposed to blast often suffer long-term brain tissue damage as well as experiencing "chronic traumatic encephalopathy (CTE)" - a condition of cognition disorder (Ropper, & Gorson, 2007). Moreover, blast wind as opposed to shock wave causes brain damage, which triggers other long-term complications including CTE. With these findings, it has easy for researchers to conduct different tests to determine the long term cognitive performance of deployed military personnel after concussion injury (Cernich, Reeves, Sun, & Bleiberg, 2007; Lew, Thomander, Chew, & Bleiberg, 2007). One of the tests included the assignment of tasks to assess the same cognitive functions of various military service personnel. The task assignment test revealed that military veterans are more likely to suffer brain damage than regular military officers. The only limitation of such a test is that it gave inconsistent results owing to the fact that the participants were assigned tasks with different levels of difficulties.

Despite the test challenges, it is now clear from existing literature that concussion injury is the primary cause of "depression," "posttraumatic stress disorder (PTSD)," and other "post-deployment symptoms" among returning military soldiers (Dretsch, Silverberg, & Iverson, 2015). From the perspective of cognitive performance, it can be argued that concussion injury affects individuals' long-term memory, information processing, and ability to perform executive functions (Dretsch, Silverberg, & Iverson, 2015). The only challenge, therefore, is to design and validate a new test that will help researchers to assess the effect of concussion injury on soldiers' cognition. The expectation of most researchers is that concussion injury will have similar effects on soldiers' cognition, and probably, a new test will allow investigators to achieve a certain level of consistency in their findings.

Given that there is a relationship between concussion sustained during military deployment and soldiers' cognition, it becomes necessary to design a test that investigates (Thomander, Chew, & Bleiberg, 2007): (1) the type of the association - whether positive or negative and (2) the degree of the relationship - whether strong or weak. The only test that will reveal both the direction and level of association between the two variables is correlation analysis.

The Current Proposal

Based on the aforementioned issues, the research proposes more challenging cognitive tasks (assignment tests) to be used in determining the association between mild brain injury (concussion) and soldiers' cognition. These tasks must be effectively assigned and parametrically increased to permit the assessment of the effect of enhancing cognitive load. The research proposes two parametric tests (tasks): (1) n-back test for assessing the cognitive performance of a deployed military officer and (2) "Paced Visual Serial Addition Test (PVSAT)" for assessing the rate of information procession. Even though the two tests have been used in some of the past studies to investigate brain disorder in general, this research will use the tasks to assess the cognitive difficulty after experiencing concussion injury.

Despite the expected positive endings such as consistent results, the test assignment has certain limitations (Thomander, Chew, & Bleiberg, 2007): (1) Little information regarding the use of the PVSAT because only a few researchers have in the past used the method to determine a range of cognitive difficulties; (2) it is challenging to sample military soldiers suffering from concussion injury - previous studies reveal intrinsic heterogeneity between people suffering from severe brain damage and cognitive performance; and (3) it is hard to differentiate between cognitive disorder caused by biological factors and those caused by neural injury or psychological responses to concussion sustained during military operations.

For the second limitation, the researcher intends to reduce inconsistency by splitting the sample using "post-concussion syndrome (PCS)" diagnosis. By spilling the sample, the researcher will be able to obtain more consistent results of cognitive deficits (Dretsch, Silverberg, & Iverson, 2015). A PCS diagnosis will give two categories of samples; (1) participants whose symptoms can resolve in a period of three months and (2) individuals whose symptoms persist and manifest after several years of injury. Moreover, other symptoms of concussion such as PTSD, Depression, memory loss, and concentration challenges are known to manifest within the early stage of recovery rather than contributing to complex conditions of brain disorder. This means that with a PCS, it will be easy for the investigator to determine at an earlier stage the possibility of a military personnel developing cognitive disorder (Dretsch, Silverberg, & Iverson, 2015). Regarding the third limitation, the researcher intends to eliminate issues of non-specificity by deploying appropriate control population for the PCS diagnosis. The study will use clinical population with PTSD, people with chronic headache, and patients with similar injuries on their bodies.

Furthermore, the researcher may consider comparing information from healthy control respondents that have syndromes that would lead to PCS during diagnosis with those individuals that already have concussion injury. The overall argument here is that in a situation where the PCS is caused through damage at the time of operation, then it can be considered that the individual with severe brain injury will perform poorly on cognitive tasks. On the contrary, the researcher expects no correlation between cognitive performance and concussion injury among control respondents.

Reliability Issues and Validity Hypotheses

It is important to remember that the research proposes two new tests, "n-back test" and "PVSAT," as methods that can be used to assess the effect of concussion injury on military soldier's cognitive behavior (Collie, et al., 2003). Furthermore, the research proposes a strong positive relationship between brain injury and cognitive processes. The specific elements of cognitive behaviour include working memory and information processing rate. However, the tests can only be reliably if they meet the expectations of the researcher, identify gaps in the current study, and suggests directions for further investigations (Collie, et al., 2003). With the limitations given above, it was necessary for the researcher to use data from participants who have experienced concussion injury for more than three months because there is a possibility that cognitive condition can reduce within a period of 3 months. In other words, it will be unreliable for the investigator to use information from patients who have experienced the disorder for a people less than three months (Collie, et al., 2003). Similarly, it would be appropriate for the researcher to compare post-concussion injury to a control population that has no head injury but other chronic pains in their bodies. Through this comparison, the researcher will be able to determine whether or not the head injury is the primary cause of cognitive condition. By considering the areas mentioned, the researcher will ensure that the information given is reliable and can be used to make certain predictions.

When it comes to validity of the investigation, the study hypothesises a strong positive correlation between concussion sustained during military deployment and soldier's cognition. As already indicated, the research process will begin by dividing the sapling population into specific groups for easy access and collection of data. The major categories for the study will include: (1) concussion injuries with PCS; (2) concussion injuries without PCS; (3) control with PCS and; (4) control without PCS. The study will only be valid if at least one of the categories will be able to report consistent PCS and severe reduction in cognition after brain injury. It is, however, expected that those individual with no head injuries will report no cognition disorder unless the condition is linked to psychological and biological issues. Moreover, it will be necessary to the researcher to evaluate the validity of the two new tests in light of their limitations to determine if the tests are good proxy for assessing the relationship between the two variables.

The following hypothesis can be to assess the validity of the new tests: if the in case the tests are valid, then the researcher should obtain persistent memory loss among soldier with concussion injuries. Secondly, if the tests are valid, then the study should reveal lower speed of information processing among military officers with concussion damages. Similarly, for military soldiers who are at higher risks of cognition, the tests should give a strong positive correlation between concussion damages, memory loss, and lower rate of information processing. However, the same tests should give negative results for control participants (healthy individuals and those with injuries in other parts of their bodies).

Determining the Psychometric Traits of the Two Test

Development of the Tests

The first test, "n-back test," will require the use of ICD-10 approach to determine concussion injury (Allen & Gfeller, 2011; Broglio, et al., 2007). The patients will be expected to demonstrate specific symptoms of brain damage including confusion or loss of awareness in a span 35 minutes or more. The researcher will take each participant's health record, which will be used as a case history. The information in the health record must include but not limited to head injury or any other possible injury in the body, time, and data of injury, and the respondent's general lifestyle. The same criteria will be used to identify the control participants but this time focusing on those individuals with no history of previous head damage.

For the PCS diagnosis, "PVSAT," the researcher will use a modified version of DSM known as DSM-IV test (Allen & Gfeller, 2011). With this test criteria, the study will reveals whether or not the respondents have the following symptoms associated with head damage: (1) nuisance, (2) dizziness, (3) hostility, and (4) anxiety. The level of PCS in respondents will be measured using the post-concussion syndrome survey (Allen & Gfeller, 2011). Just like the previous test procedure, the "PVSAT" will be applied to control participants to determine similar cases of head trauma.

Sample Design, Sample Group, and Test Procedure

The researcher will use convince sampling to identify individuals with brain injuries and possible instances of cognitive challenges. Similarly, the sampling procedure will help the investigator to obtain healthy individuals as well as those who have injuries in other parts of their bodies (Cernich, et al., 2007). The researcher expects to use a sample size of N=48 that will be divided according to the following categories: (1) n=12 for respondents who have suffered concussion injuries and cognition challenges; (2) n=12 for individuals who have suffered concussion injuries but no cognition disorder; (3) n=12 for control participants who have suffered cognition without history of concussion injuries; and (4) n=12 for individuals who have no history of cognition challenges or concussion injury.

The respondents will be expected to complete two behavioural assignments; one for the n-Back test and the other for the PVSAT. The n-Back test will permit a four scale response rated as 1, 2, 3, and 4-Back with each score presented after an interval of 4 seconds. Computer automated keyboards, K and L, will be used as the decision button where a participant will be expected to press K for a target response and L for a non-target response (Schatz & Browndyke, 2002). The fact that the 0 value corresponds to the near ceiling condition for all the respondents means that it can be used to determine the performance validity. The PVSAT test will be operated on five conditions rated at intervals of 0.5 seconds beginning from 3 seconds, 2.5 seconds, 2 seconds, and 1.5 seconds to 1.0 seconds. The five conditions will be presented together with the four n-back numbers (Schatz & Browndyke, 2002). Two numbers from the two tests will be matched to determine whether a response is positive for both cognition disorder and concussion injury. The data collected from the two tests will be analysed using "One-Way ANOVA" test and "t-tests" to assess a statistics difference between the sample groups.

Possible Outcomes

If the tests applied are valid, the researcher should expect a strong positive correlation between brain damage or concussion injury and cognition challenges (Theeler, Flynn, & Erickson, 2012). The study should demonstrate a consistent reduction in memory response and lower rate of information processing among respondents with head trauma (sample group 1, respondents who have suffered concussion injuries and cognition challenges). However, if the tests are invalid, the researcher should expect variations in result between respondents with head trauma and those without head trauma (Theeler, Flynn, & Erickson, 2012). For instance, if the two tests give a strong positive correlation in sample category (4), "individuals who have no history of cognition challenges or concussion injury," then the two tests must be invalid.

Conclusion

Military officers report severe cognitive challenges after experiencing mild traumatic brain injuries. Assessing the effect of concussion sustained during a military deployment on soldiers' cognition is necessary because it facilitates the activities of the military by ensuring that only officers who are sane are deployed in the field (Drag, et al., 2012). Testing the effect of brain injury on memory functions and information processing has never been easy. However, with the two tests (n-Back and PVSAT), the researcher is optimistic that the study will give a new dimension to psychometric analysis of deployed military soldiers' cognition. Ideally, the tests will help to identify those with cognitive challenges (Drag, et al., 2012; Theeler, Flynn, & Erickson, 2012). As such, the military department and health care providers will have the opportunity to deliver the best subscriptions and care services for the affected military personnel.

References

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Broglio, S. P., Ferrara, M. S., Macciocchi, S. N., Baumgartner, T. A., & Elliot, R. (2007). Test-retest reliability of computerized concussion assessment programs. Journal of Athletic Training, 42(4), 509-514.

Cernich, A., Reeves, D., Sun, W., & Bleiberg, J. (2007). Automated Neuropsychological Assessment Metrics sports medicine battery. Archives of Clinical Neuropsychology, 22(Suppl. 1), S101-S114. doi: 10.1016/j.acn.2006.10.008.

Collie, A., Maruff, P., Makdissi, M., McCrory, P., McStephen, M., & Darby, D. (2003). CogSport: Reliability cognitive tests used in and correlation with conventional postconcussion medical evaluations. Clinical Journal of Sport Medicine, 13(1), 28-32. doi: 10.1097/00042752-200301000-00006.

Drag, L. L., Spencer, R. J., Walker, S. J., Pangilinan, P. H., & Bieliauskas, L. A. (2012). The contributions of self-reported injury characteristics and psychiatric symptoms to cognitive functioning in OEF/OIF veterans with mild traumatic brain injury. Journal of the International Neuropsychological Society, 18(3), 576-584. Doi: 10.1017/S1355617712000203.

Dretsch, M. N., Silverberg, N. D., & Iverson, G. L. (2015). Multiple past concussions are associated with ongoing post-concussive symptoms but not cognitive impairment in active-duty army soldiers. Journal of neurotrauma, 32(17), 1301-1306. Doi: doi/abs/10.1089/neu.2014.3810.

Lew, H. L., Thomander, D., Chew, K. T. L., & Bleiberg, J. (2007). Review of sports-related concussion: Potential for application in military settings. Journal of Rehabilitation Research and Development, 44(7), 963-973. doi: 10.1682/Jrrd.2006.12.0169.

Ropper, A. H., & Gorson, K. C. (2007). Concussion. New England Journal of Medicine, 356(2), 166-172. doi: 10.1056/NEJMcp064645.

Schatz, P., & Browndyke, J. (2002). Applications of computer-based neuropsychological assessment. Journal of Head Trauma Rehabilitation, 17(5), 395-410. doi: 10.1097/00001199-200210000-00003.

Theeler, B. J., Flynn, F. G., & Erickson, J. C. (2012). Chronic daily headache in US soldiers after concussion. Headache: The Journal of Head and Face Pain, 52(5), 732-738. Doi: 10.1111/j.1526-4610.2012.02112.