to luminance, color of the perceived light can also influence the duration of a constriction. For example, while blue light leads to sustained constriction of the pupil beyond 1500 ms, red light leads to a degree of re-dilation in the absence of light change, termed pupil escape (Mathôt,...
As shown inFigure 4.9,pupil dilationcan be used to measure task difficulty. Participants interacted with a web-based TV diary tool: one had difficulty accessing the search function (shown in red), and the other had no difficulty (shown in blue). The participant who had difficulty had greate...
Iris dilation/constriction is affected by emotion as well as by ambient light. People can train themselves to consciously lower the heart rate, which is also affected by emotion as well as by environmental factors. So I wonder if an observer can train themselves to more fully dilate the iris?
P. (2014). Fractal images induce fractal pupil dilations and constrictions. International Journal of Psychophysiology, 93(3), 316-321. doi:https://doi.org/10.1016/j.ijpsycho.2014.06.013Moon, P., Muday, J., Raynor, S., Schirillo, J., Boydston, C., Fair- banks, M. S., and ...
Pupil dilation has been reliably identified as a physiological marker of consciously reportable mental effort. This classical finding raises the question of whether or not pupil dilation could be a specific somatic signature of conscious processing. In order to explore this possibility, we engaged healt...
Conversely, relaxation can result in pupil constriction. Pupil anatomy is also fairly straightforward. Pupil contraction and dilation are controlled by two smooth muscles of the iris. The pupillary reflex is what allows the pupil to constrict and dilate involuntarily. It is important to remember the...
(displaced-lines stimuli), to all stimulus types, both white and black. As expected, the pupil constricted for white-dot stimuli and dilated for black-dot stimuli. The light-evoked constriction was predictably faster than the dark-evoked dilation21, but combining the two (by subtracting the ...
If our eye remains at 7mm dilation as the exit pupil becomes smaller at high magnification, then the final aperture on our eye is now smaller than 7mm. Say the exit pupil is 1mm, then our "refractor" is working at 1mm at f/20. The image on our eye is much "slower" than f/3 th...
Additional enhanced PLR metrics (higher average constriction velocity, 3.08 mm/s vs 2.50 mm/s; difference, 0.58; 99.4% CI, 0.36-0.81), peak constriction velocity (4.88 mm/s vs 3.91 mm/s; difference, 0.97; 99.4% CI, 0.63-1.31), average dilation velocity (1.32 mm/s vs 1.22 mm/s, ...
(Saper et al., 1976;Holstege, 1987;Pyner and Coote, 2000;Nunn et al., 2011). Stimulation of these regions of the hypothalamus results in pupil dilation while lesioning this region results in miosis (pupil constriction) and reduction ofpupillary reflexdilation (Sano et al., 1970;Kalyan...