AbstractsPsychology

One in four Americans aged 65 years or older is clinically depressed. A growing body of research suggests subclinical depression influences mood, affect, cortisol dysregulation, and autonomic imbalance. Depression is an independent risk factor for cardiovascular disease. Posited to underlie these changes are shifts in sympathovagal balance toward excessive sympathetic arousal and/or decreased vagal inhibitory influences on the heart rate. Nine studies suggest a 10-minute fast and variable thinking (FVT) exercise improves mood in nonsymptomatic student populations. This randomized, double-blind, placebo-controlled study investigated pre-to-post FVT effects on mood, perception of thought speed, depression severity, and changes in physiology, that is, heart rate variability (HRV), temperature, and electrodermal response (EDR) in 30 subclinical depressed females aged 50 to 69 as compared to paired controls. A paired samples t-test was run to assess mean FVT changes in mood, depression severity, and physiology using the PANAS-X, Zung Self-Rating Depression Scale, HRV, temperature, and EDR, respectively. A linear regression and ANOVA measured within and between group changes in positive mood and perception of thought speed. The results showed that fast and variable thinking decreased negative mood (p = .04) and depression severity (p = .02) while maintaining positive mood levels. Perception of thought speed had a very weak mediating effect. Physiologically, %HF (p = .04) and Temperature (p = .002) decreased below baseline post-intervention. Respiration Rate (RSP) did not recover post-intervention. %HF, Temperature, and RSP suggest a possible hypo-parasympathetic response. Relative pre-to-post mean increases in SDNN, RMSSD, pNN50, and HRV Amplitude values in conjunction with EDR recovery suggest resilience and a positive health status. Disparate findings post-intervention may be age and health related. Additional research is needed to determine if the initial sympathetic arousal eventuates in improved health long term. This study suggests it is possible to feel less depressed and less negative without feeling subjectively positive. There is sufficient evidence to suggest that fast and variable thinking may be an effective tool for improving mood in subclinical depressed women.