Purchase this article with an account.
Xiaofei Hu, Rumi Hisakata, Hirohiko Kaneko; Effects of attention and spatial frequency on pupillary response. Journal of Vision 2019;19(8):40. doi: https://doi.org/10.1167/19.8.40.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
When people look at grating stimulus, their pupils constrict the most when spatial frequency of the grating is within the range of 2.67c/d – 5.33c/d. In this study, we investigate how pupil responds to grating stimulus when people covertly attend to it. Moreover, we focus on both pupil’s sustained and transient responses, because the claim in the previous related researches are all based on initial constriction(transient) of pupillary response elicited by stimulus onset. In experiment 1, stimulus was composed of two semicircular gratings having different spatial frequencies in the left and right visual field and a fixation dot at the center. Participants were asked to look at the fixation throughout experiment while change their attentional direction, left, right or middle, according to a cue. Results showed that initial maximum constriction(transient) didn’t differ significantly with attentional direction, whereas sustained stable response did for different spatial frequencies as in the data for direct viewing. In experiment 2, we used a stimulus in which high-pass filtered and low-pass filtered natural images were superimposed. Participants were asked to attend to either component of the stimulus. Significant difference in both initial maximum constriction and sustained state of pupillary response was showed depending on the image to attend, high-pass filtered or low-pass filtered image. In conclusion, attention mediates the influence of stimulus spatial frequency on both pupil’s transient and sustained responses as in the case of direct viewing, although the influence on transient response is not so robust.
This PDF is available to Subscribers Only