Semi-autonomous driving significantly reduced the LF/HF ratio compared to manual driving (1.7 vs 2.9, p<0.001), indicating decreased sympathetic dominance.
Does semi-autonomous driving improve heart rate variability and reduce anxiety compared to manual driving in healthy adults?
Semi-autonomous driving may reduce psychophysiological stress and anxiety compared to manual driving, as evidenced by improved heart rate variability metrics.
Standardized Mean Difference: 1.05 (95% CI 0.72–1.36)
Absolute Event Rate: 1.7% vs 2.9%
p-value: p=<0.001
Objective: Traditional driving imposes substantial cognitive and physical demands on drivers, often contributing to stress, fatigue, and increased cardiovascular risk. Semi-autonomous driving technologies may alleviate these burdens. We aimed to evaluate the effects of semi-autonomous driving on autonomic nervous system activity and anxiety by comparing heart rate variability (HRV) and validated anxiety measures with manual driving. Methods: Forty-five healthy adults underwent HRV analysis using Holter monitoring while driving the same route under manual and semi-autonomous conditions. Frequency-domain (Low-frequency LF/high-frequency HF ratio), time-domain (standard deviation of NN intervals SDNN, root mean square of successive differences RMSSD, percentage of successive RR intervals that differ by more than 50ms pNN50), and non-linear indices (sample entropy, detrended fluctuation analysis DFA α1) were assessed. Mean heart rate, maximum heart rate, and minimum heart rate were also analyzed. Anxiety was evaluated with the State-Trait Anxiety Inventory (STAI; range 20–80) and a 10-point Visual Analog Scale (VAS). Results: There were 22 male and 23 female participants. The mean age was 34.7±6.9 years. Semi-autonomous driving was associated with significantly lower LF/HF ratio compared with manual driving (1.7±0.5 vs. 2.9±0.7, p<0.001). Time-domain HRV indices improved, with higher SDNN (61.5±10.1 vs. 43.6±8.9 ms), RMSSD (47.8±8.3 vs. 29.1±6.8 ms), and pNN50 (23.5±6.2% vs. 12.9±4.6%; all p<0.001). Non-linear measures showed increased sample entropy (1.41±0.27 vs. 1.14±0.22, p<0.01) and reduced DFA α1 (1.04±0.13 vs. 1.18±0.15, p<0.01). Mean heart rate decreased from 82.4±9.1 to 75.8±8.3 bpm (p<0.001). Anxiety outcomes paralleled these findings: VAS scores were lower (3.7±0.8 vs. 6.1±1.0, p<0.001) and STAI-State decreased (38.4±6.1 vs. 47.1±6.5, p<0.001), while STAI-Trait remained unchanged (43.5±6.8 vs. 45.0±7.3, p=0.12). Conclusion: Semi-autonomous driving reduced sympathetic dominance and anxiety while enhancing parasympathetic activity and HRV complexity. These findings suggest potential psychophysiological benefits of semi-autonomous driving, warranting confirmation in larger and more diverse populations.
Göçer et al. (Mon,) conducted a other in Healthy adults (n=45). Semi-autonomous driving (SAE Level 2) vs. Manual driving was evaluated on Within-subject change in LF/HF ratio (SMD 1.05, 95% CI 0.72-1.36, p=<0.001). Semi-autonomous driving significantly reduced the LF/HF ratio compared to manual driving (1.7 vs 2.9, p<0.001), indicating decreased sympathetic dominance.