. 2015 Dec 1;5:17610. doi: 10.1038/srep17610

Table 1. Definitions for the PLR metrics during light stimulation and PIPR metrics after light offset (following Adhikari et al., 2015⁷).

Metrics	Definition and Units
Baseline pupil diameter (BPD)	Average 5 s pre-stimulus period (mm, %)
PLR Metrics
Transient PLR	Peak % change from 180–500 ms after light onset¹¹,³⁴
Peak pupil constriction	Minimum pupil size (% baseline) during light presentation
PIPR Metrics
6 s PIPR amplitude	Pupil size (% baseline) at 6 s after light offset⁸,³²,⁴⁹
Plateau PIPR	Plateau of exponential model (% baseline)⁸
AUC early	∑ (BPD - APD)^* over 0–10 s after light offset (unitless)⁵⁰
AUC late	∑ (BPD - APD) over 10–30 s after light offset (unitless)⁵⁰

*APD = absolute pupil diameter.

Table 1. Definitions for the PLR metrics during light stimulation and PIPR metrics after light offset (following Adhikari et al., 20157).