Faculty Bibliography

Objective(s): To determine if relationship between heart rate variability/ HRV and problem-solving is moderated by positive affect. Design: Quasi-experimental. Setting: Community-based structured day program. Participants: Thirteen individuals, aged 23-63 years with severe, chronic brain injury (13-40 years post-onset). Interventions: HRV biofeedback. Main Outcome Measure(s): PANAS positive affect/PANAS-PA; category test/CT; HRV- index (coherence ratio/CR). Results: Bivariate regression using HRV-CR to predict CT revealed moderately-large effect size, with trend towards significance, p=.085, ES(r) =.50. Similar overall interaction effect was observed when PANAS-PA was added as moderator, p=.07, ES (R²) =.23. Johnson Neyman technique revealed that when PANAS-PA was low, coherence did not have significant relationship with improvements in CT. However, when PANAS-PA was >5.79 above the mean (>36.64), the effect of coherence was in the expected negative direction (lower scores in CT reflect better performance) and significant, with large effect size, p<.05, ES(r) >.60. Conclusions: Published studies demonstrate significant association between problem-solving and HRV (Thayer, 2006; Porges, 2001). This sample demonstrated moderate-to-large main effect for HRV, which did not reach statistical significance. Taking into account levels of positive affect clarified the relationship and revealed that the effect of HRV on problem-solving was larged and statistically significantd when positive affect was high. The significant role of PANAS-PA in moderating problem solving performance is consistent with literature which found positive affect increases mental flexibility, creativity, and coping behaviors (Ashby, 1999; Damasio & Carvalho, 2013). Results are conceptually congruent with contemporary problem-solving cognitive rehabilitation models (e.g., Rath et al., 2011) and consistent with Shewchuk et al.'s (2000) study of healthy adults where negative problem-orientationdbeliefs and attitudes about one's own problem-solving abilitydimpeded objective performance on CT. These findings have important implications for addressing affect and problem-orientation in cognitive rehabilitation; dispositions to harbor pessimism about self might impede motivation for/attainment of meaningful, goal-directed behavior

This article describes a study using heart rate variability (HRV) biofeedback to treat emotional dysregulation in 13 individuals with severe chronic brain injury. Measures included HRV indices, tests of attention and problem solving, and informant reports of behavioral regulation. Results demonstrated that individuals with severe brain injury were able to learn HRV biofeedback and increase coherence between the parasympathetic and sympathetic nervous systems. Individuals who attained the greatest coherence were rated as being able to best regulate their emotions and behavior.