Cognitive rehabilitation can be very broadly defined as any therapy directed at restoring cognitive functioning back to an individual’s previous level or ability.
Now the definitions split further into compensation and remediation.
Compensation is the addition of strategies to bypass the cognitive impairment. The key here is that we are not changing the individual’s ability, instead we achieve improved function through use of an additional tool.
Remediation is focused on restoring impaired skills through training specific domains of functioning. Function is improved through targeting the person’s ability.
Time for the obligatory sports analogy. Dr. Chugh challenges Dr. Boulanger to a race, a 100 m swim. Dr. Boulanger is not as good a swimmer as Dr. Chugh, she used to be, but now she has better things to do. Now Dr. Boulanger can a) use compensation and wear a pair of flippers and swim faster than Dr. Chugh (it’s not cheating, she’s being smart here), or b) she can use remediation and train hard every day to develop the skill required to beat Dr. Chugh.
Assuming that you made the great decision to read part one of this wonderfully written article, you remember that after a concussion, cognition typically does return to baseline functioning, even without any intervention. This means that best practice, as laid out in several guidelines, is, for all intents and purposes, just to wait it out, although, remediation may aid in a faster return to baseline cognitive functioning, and may be necessary for the rare few for whom cognition is not returning to baseline functioning without help. Let us explore the evidence.
Somewhat surprisingly, there really is not a lot of research in regards to cognitive rehabilitation after a concussion. Best practice, according to recent guidelines put out by the Ontario Neurotrauma Foundation (ONF; 2018) and the Centers for Disease Control and Prevention (2018) suggest the use of evidence-based neurorehabilitation strategies, appropriate to the etiology of the impairment, yet neither guideline specifies as to what these might be. Cognitive rest is advised, but no time period is outlined. Thus we know that we should do something to aid in cognitive functioning, but we do not know what, and do not know when. Is it more beneficial to wait for recovery and use compensation in the short-term, or is it best to get started on remediation early on?
Let us begin first with that cognitive rest period. Cognitive rest is a staple recommendation in most guidelines and is essentially the reduction of intellect stimulating activity during the first stage of that concussion recovery. Now it is very easy to say, for example, avoid math problems, Tolstoy, and solving world hunger. Then it gets complicated. Does a board game violate this rule, or cooking, or listening to a podcast? There are no hard and fast rules or definitions of cognitive rest. According to the consensus statement from the concussion in sport conference, cognitive rest is avoidance of all activity requiring increased attention (McCrory et al., 2013), which really could refer to anything that you do actively, or passively, for a prolonged time. A literature review on cognitive rest after concussion came to the conclusion that approximately one or two days of cognitive rest was adequate (Eastman & Chang, 2015). That is the basis of the model that most clinicians recommend, rest for 24 to 48 hours, and then a gradual increase in activity.
Now after that period of rest, we can implement rehabilitation, such as compensation or remediation. Compensation is one of those evidence-based neurorehabilitation strategies suggested by the guidelines (CDC, 2018; ONF, 2018). There was a randomized control trial done on a sample of American veterans that had a history of mild traumatic brain injury, where the experimental group went through 10 weeks of compensatory cognitive training (Caplan et al., 2017). The group with the compensation training scored significantly better than the control group, not just on self reported cognitive impairment, but also on objective measures of attention, memory, verbal fluency, and executive functioning. Another study on a similar sample of American veterans, this time with mild to moderate traumatic brain injury, went through a year of either supported employment, or supported employment in addition to compensatory cognitive training (Twamley et al., 2015). This study did not find too many differences between the groups on cognitive performance, other than prospective memory (memory for things to come e.g., upcoming appointments with the treating team) and affective symptoms (mood related symptoms e.g. lack of motivation to do Moe’s recommended cardiovascular exercises). Essentially compensation is likely beneficial, but we definitely need more research.
There are a couple of literature reviews on cognitive rehabilitation after brain injury, but an important fact to note is that these studies do not differentiate between severity of injury. This becomes a problem as the prognosis in regards to cognition is incredibly different for someone with a severe brain injury (including individuals missing portions of their brain) and a very mild one, such as a concussion. Additionally, many studies group acquired brain injuries together, which include strokes. When looking at mixed brain injury samples, cognitive rehabilitation has shown to result in improvements in cognition (Bogdanova, Yee, Ho, & Cicerone, 2016; Cicerone et al., 2011; Hallock et al., 2016). When we break it down to cognitive domains, there seems to be improvement in executive functioning with a small effect size (Bogdanova et al., 2016; Hallock et al., 2016), verbal memory with a moderate effect size (Hallock et al., 2016), and attention (Bogdanova et al., 2016). We can also look at the effectiveness of computerized cognitive remediation in other populations with less severe cognitive impairment, perhaps more in line with concussion than a broad brain injury population. Studies with major depressive disorder (Motter et al., 2016) and cognitively-healthy older adults (Lampit, Hallock, & Valenzuela, 2014) generally yield small to moderate effect sizes of cognitive remediation, across all cognitive domains. Essentially, it is very likely that computerized cognitive remediation will be beneficial for those with cognitive impairments after concussion, yet research should be conducted before we can draw this conclusion.
Bogdanova, Y., Yee, M. K., Ho, V. T., & Cicerone, K. D. (2016). Computerized cognitive rehabilitation of attention and executive function in acquired brain injury: A systematic review. The Journal of Head Trauma Rehabilitation, 31(6), 419. doi:10.1097/HTR.0000000000000203.
Caplan, B., Bogner, J., Brenner, L., Storzbach, D., Twamley, E. W., Roost, M. S., … & Turner, A. P. (2017). Compensatory cognitive training for operation enduring freedom/operation Iraqi freedom/operation new dawn veterans with mild traumatic brain injury. Journal of Head Trauma Rehabilitation, 32, 16-24. doi:10.1097/HTR.0000000000000228
Cicerone, K. D., Langenbahn, D. M., Braden, C., Malec, J. F., Kalmar, K., Fraas, M., … & Azulay, J. (2011). Evidence-based cognitive rehabilitation: updated review of the literature from 2003 through 2008. Archives of Physical Medicine and Rehabilitation, 92(4), 519-530. doi10.1016/j.apmr.2010.11.015
Eastman, A., & Chang, D. G. (2015). Return to learn: A review of cognitive rest versus rehabilitation after sports concussion. Neurorehabilitation, 37(2), 235–244. https://doi.org/10.3233/NRE-151256
Hallock, H., Collins, D., Lampit, A., Deol, K., Fleming, J., & Valenzuela, M. (2016). Cognitive training for post-acute traumatic brain injury: A systematic review and meta-analysis. Frontiers in Human Neuroscience, 10, 537. doi:10.3389/fnhum.2016.00537
Lampit, A., Hallock, H., & Valenzuela, M. (2014). Computerized cognitive training in cognitively healthy older adults: A systematic review and meta-analysis of effect modifiers. PLoS Medicine, 11(11), e1001756. https://doi.org/10.1371/journal.pmed.1001756
Lumba-Brown, A., Yeates, K. O., Sarmiento, K., Breiding, M. J., Haegerich, T. M., Gioia, G. A., … & Joseph, M. (2018). Centers for Disease Control and Prevention guideline on the diagnosis and management of mild traumatic brain injury among children. JAMA Pediatrics, 172(11), e182853-e182853.
McCrory, P., Meeuwisse, W. H., Aubry, M., Cantu, B., Dvora ́k, J., Echemendia, R. J., … & Turner, M. (2013). Consensus statement on concussion in sport: The 4th International Conference on Concussion in Sport held in Zurich, November 2012. British Journal of Sports Medicine, 47(5), 250-258. doi:10.1136/bjsports-2013-092313
Motter, J. N., Pimontel, M. A., Rindskopf, D., Devanand, D. P., Doraiswamy, P. M., & Sneed, J. R. (2016). Computerized cognitive training and functional recovery in major depressive disorder: A meta-analysis. Journal of Affective Disorders, 189, 184-191. https://doi.org/10.1016/j.jad.2015.09.022
Ontario Neurotrauma Foundation (2018). Guidelines for concussion/mTBI and persistent symptoms (3rd ed.). Toronto, ON: Ontario Neurotrauma Foundation
Twamley, E. W., Thomas, K. R., Gregory, A. M., Jak, A. J., Bondi, M. W., Delis, D. C., & Lohr, J. B. (2015). CogSMART compensatory cognitive training for traumatic brain injury: Effects over 1 year. The Journal of Head Trauma Rehabilitation, 30(6), 391–401. https://doi.org/10.1097/HTR.0000000000000076