SD2/SD1 ratio

SD2/SD1 ratio is associated with visuospatial function in humans (rs = .19, p < 0.05).

“SD2/SD1 ratio and Block Design test ( r s = .19, n = 140, p < 0.05)”

Humansn = 140

Evaluating the relationship between time‐domain indices of ultra‐short term heart rate variability and cognition: Findings from the Singapore Longitudinal Ageing Study

AAIC 2025 abstract·9 Jan 2026

SD2/SD1 ratio is associated with delayed recall in humans (rs = .22, p < 0.05).

“SD2/SD1 ratio and RAVLT delayed recall ( r s = .22, n = 139, p < 0.05)”

Humansn = 139

Evaluating the relationship between time‐domain indices of ultra‐short term heart rate variability and cognition: Findings from the Singapore Longitudinal Ageing Study

AAIC 2025 abstract·9 Jan 2026

SD2/SD1 ratio is associated with immediate memory in humans (rs = .22, p < 0.01).

“There were positive and significant correlations observed between SD2/SD1 ratio and RAVLT immediate memory ( r s = .22, n = 140, p < 0.01)”

Humansn = 140

Evaluating the relationship between time‐domain indices of ultra‐short term heart rate variability and cognition: Findings from the Singapore Longitudinal Ageing Study

AAIC 2025 abstract·9 Jan 2026