Spencer Liebel and Dr. Michael Larson, Department of Psychology
The goal of this project was to clarify the additive role that negative affect plays in the capacity for individuals with moderate-to-severe (M/S) traumatic brain injury (TBI) to acquire new learning. Traumatic brain injury is the leading cause of death and disability in the United States, affecting an estimated 1.7 million people annually. Traumatic brain injuries typically result in considerable long-term neurological disabilities such as deficits in attention, memory, and processing speed (Zaloshnja, Miller, Langlois, & Selassie, 2008). In addition, TBI survivors are significantly more likely to develop psychiatric disorders, including depression and anxiety, and attempt suicide at a higher rate than those without TBI (Silver, Kramer, Greenwald, & Weissman, 2001). Negative affect is a construct that describes the symptoms of affective distress that include both depression and anxiety symptoms (Clark & Watson, 1991). Negative affect may also impair new learning abilities (Dux et al., 2008). The combined deficits of TBI and negative affect may pose a substantial barrier to rehabilitation and helping TBI survivors to improve their quality of life. Despite the prevalence of depression and anxiety in individuals with TBI, this is the first study that we are aware of that addressed the effects negative affect has on the acquisition of new learning amongst TBI survivors. Acquiring new information (e.g. life skills, behavioral adaptations, learning, etc.) is a key function of TBI rehabilitation programs, and understanding how negative affect influences new learning capabilities in TBI survivors is an invaluable addition to the field of TBI rehabilitation research. This study has contributed knowledge that will help TBI survivors, caregivers, and clinicians more effectively manage and treat both emotional and cognitive deficits following injury.
Participants
19 individuals with M/S TBI and 11 healthy controls were recruited to participate in this study. Participants were considered to have sustained a M/S TBI if they had a minimum Glasgow Coma Scale score 12 or below and had been unconscious for at least 30 minutes.
Results
As hypothesized, we found that on error trials, reaction times were faster for error-less learning (EL) versus error-full learning (EF) conditions. These preliminary results suggest that EL cognitive rehabilitation improves the efficiency/speed of reaction times over EF methods. Furthermore, negative affect is correlated with reaction times in both conditions, but not overall accuracy. These results are congruent with previous research highlighting the disruptive impact of negative affect on cognitive performance (Larson , Fair, Farrer, & Perlstein, 2011). This emphasizes the role that emotional functioning may have on behavioral performance and that treating negative affect is a critical component for cognitive rehabilitation after TBI.
We were able to disseminate our findings to a broader audience through a poster presentation at the 2012 Mary Lou Fulton Conference at Brigham Young University. The poster presented our findings in pilot study format, and took 2nd place in the undergraduate division. Additionally, this research resulted in an abstract and poster that will be presented to the 41st Annual International Neuropsychological Society Conference in Waikola, Hawaii, February 2013.
Limitations
While the research hypothesis and collected data successfully corroborated with previous findings in the TBI rehabilitation field, several unforeseen difficulties arose that hindered the study. First, participant recruitment proved to be difficult. We proposed to recruit 25 individuals with M/S TBI who had no additional psychiatric or physical impairments by the end of May 2012. Unfortunately, at the time of the writing of this report, we were only able to properly screen and include 19 participants. The very nature of TBI injuries contributed to this difficulty. That is, individuals with M/S TBI have difficulties with planning, memory, and every-day skills (e.g. checking email, returning phone calls, etc.). Additionally, we originally planned to recruit a “clean” sample of participants (that is, people with no psychiatric or medical complications beside TBI). However, “clean” does not necessarily mean “real” because TBIs are associated with multiple comorbidities both before and after injury. We have plans to adjust our screening criteria to be more reflective of TBI populations in this regard. By including individuals who have other mental and/or physical problems in addition to TBI, we will more accurately reflect TBI populations and speed up participant recruitment.
Conclusion
The benefits of EL on TBI cognitive rehabilitation are replicated in that the TBI group had improved reaction times (but still slower than controls), as well as better accuracy in the EL vs. EF condition. While poor mood did not appear to play a role in performance, anxiety and positive affect did correlate with reaction time, suggesting vigilance and positive mood may assist behavioral indices of cognition in this sample.
References
- Clark, L.A., & Watson, D. (1991). Tripartite model of anxiety and depression: Psychometric evidence and taxonomic implications. Journal of Abnormal Psychology, 100(3), 316-336. doi:10.1037/0021-843X.100.3.316
- Dux, M.C., Woodard, J. L., Calamari, J. E., Messina, M., Arora, S., Chik, H., & Pontarelli, N. (2008). The moderating role of negative affect on objective verbal memory performance and subjective memory complaints in healthy older adults. Journal of the Internation Neuropsychological Society, 14(2), 327-336. doi:10.1017/S135561770808363
- Larson, M. J., Fair, J. E., Farrer, T. J., & Perlstein, W. M. (2011). Predictors of performance monitoring abilities following traumatic brain injury: The influence of negative affect and cognitive sequelae. International Journal of Psychophysiology, 81(3). doi:10.1016/j.ijpsycho.2011.02.001
- Silver, J. M., Kramer, R., Greenwald, S., & Weissman, M. A. (2001). The association between head injuries and psychiatric disorders: Findings from the New Haven NIMH Epidemiologic Catchment Area Study. Brain Injury, 15(11), 935-945. doi:10.1080/02699050110065295
- Zaloshnja, E., Miller, T., Langlois, J. A., & Selassie, A. W. (2008). Prevalence of long-term disability from traumatic brain injury in the civilian population of the United States, 2005. The Journal of Head Trauma Rehabilitation, 23(6), 394-400. doi:10.1097/01.HTR.0000341435.52004.ac