A U-shaped relationship between perceived chronic stress and the approach motivation: evidence from resting-state EEG.
This study indicates a U-shaped relationship between chronic stress and approach motivation, suggesting that both low and high stress levels may enhance motivation, while moderate stress may reduce it.
Where it sits
this study against the rest of the dsip corpusSummary and findings
This study measured the relationship between chronic stress and resting-state EEG measures of approach motivation in sixty undergraduate students. Significant quadratic associations were found between perceived stress and EEG measures, including alpha frontal asymmetry, delta power, and theta power. The findings suggest a U-shaped relationship, where both low and high chronic stress levels enhance approach motivation.
Abstract
Chronic stress facilitates the development and progression of multiple psychiatric disorders, including depression and addiction. The dysregulation of approach motivation has been proposed as a mechanism of chronic stress, but it is unclear how chronic stress is related to approach motivation. The current study sought to elucidate the relationship between chronic stress and resting-state electroencephalographic (EEG) measures of approach motivation. Sixty undergraduate students filled out the Perceived Stress Scale (PSS) and were recorded with resting-state EEG. Hierarchical regression analyses revealed significant quadratic (U-shaped) associations between mean-centered PSS scores and all three EEG measures: alpha frontal asymmetry (AFA) (<i>β</i> = 0.32, 95% CI [0.0001, 0.0018], <i>p</i> = 0.032), delta power (<i>β</i> = 0.33, 95% CI [0.0003, 0.0036], <i>p</i> = 0.021), and theta power (<i>β</i> = 0.31, 95% CI [0.0002, 0.0035], <i>p</i> = 0.030). All quadratic effects remained statistically significant after false discovery rate (FDR; Benjamini-Hochberg) correction (all adjusted <i>ps</i> < 0.05). These findings suggest that there is a nonlinear relationship between chronic stress and approach motivation, i.e. at both low and high chronic stress levels, resting-state activation of approach motivation is enhanced, whereas at moderate chronic stress levels, approach motivation is reduced, probably reflecting more efficient allocation and conservation of brain resources. More importantly, our findings demonstrate the necessity of examining the baseline neural state in addition to the task-evoked responses when assessing stress-related changes of approach motivation, thereby providing novel insights into the mechanisms of stress adaptation and their implications for psychological health.
Background
The study addresses the relationship between chronic stress and approach motivation, which is relevant for understanding psychiatric disorders. Previous research has indicated that chronic stress can influence motivation, but the specific nature of this relationship remains unclear. This study aims to clarify how chronic stress correlates with resting-state EEG measures of approach motivation.
Methods
The study involved sixty undergraduate students who completed the Perceived Stress Scale (PSS) and underwent resting-state EEG recordings. Hierarchical regression analyses were conducted to assess the relationship between PSS scores and EEG measures. The primary outcome measures included alpha frontal asymmetry, delta power, and theta power.
Results
The primary endpoint revealed significant quadratic associations between PSS scores and EEG measures. Specifically, alpha frontal asymmetry showed β = 0.32, p = 0.032, delta power showed β = 0.33, p = 0.021, and theta power showed β = 0.31, p = 0.030. All quadratic effects remained statistically significant after FDR correction.
Interpretation
These findings indicate a nonlinear relationship between chronic stress and approach motivation, which aligns with some prior literature suggesting that both low and high stress can enhance motivation. However, the effect sizes, while statistically significant, may not be clinically meaningful. Limitations such as the small sample size and reliance on self-reported measures may confound the conclusions drawn from the study.
Key findings
- β = 0.32, 95% CI [0.0001, 0.0018], p = 0.032 for alpha frontal asymmetry.
- β = 0.33, 95% CI [0.0003, 0.0036], p = 0.021 for delta power.
- β = 0.31, 95% CI [0.0002, 0.0035], p = 0.030 for theta power.
- All quadratic effects remained statistically significant after FDR correction (all adjusted ps < 0.05).
- At both low and high chronic stress levels, resting-state activation of approach motivation is enhanced.
Limitations
- small n=60 undergraduates
- self-reported stress measures may introduce bias
- cross-sectional design limits causal inference
- lack of diverse population may affect generalizability