“Blue Sky Effect”: Contextual Influences on Pupil Size During Naturalistic Visual Search

Pupil size is influenced by cognitive and non-cognitive factors. One of the strongest modulators of pupil size is scene luminance, which complicates studies of cognitive pupillometry in environments with complex patterns of visual stimulation. To help understand how dynamic visual scene statistics influence pupil size during an active visual search task in a visually rich 3D virtual environment (VE), we analyzed the correlation between pupil size and intensity changes of image pixels in the red, green, and blue (RGB) channels within a large window (~14 degrees) surrounding the gaze position over time. Overall, blue and green channels had a stronger influence on pupil size than the red channel. The correlation maps were not consistent with the hypothesis of a foveal bias for luminance, instead revealing a significant contextual effect, whereby pixels above the gaze point in the green/blue channels had a disproportionate impact on pupil size. We hypothesized this differential sensitivity of pupil responsiveness to blue light from above as a “blue sky effect,” and confirmed this finding with a follow-on experiment with a controlled laboratory task. Pupillary constrictions were significantly stronger when blue was presented above fixation (paired with luminance-matched gray on bottom) compared to below fixation. This effect was specific for the blue color channel and this stimulus orientation. These results highlight the differential sensitivity of pupillary responses to scene statistics in studies or applications that involve complex visual environments and suggest blue light as a predominant factor influencing pupil size.

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Listener’s personality traits predict changes in pupil size during auditory language comprehension

Scientific Reports ◽

10.1038/s41598-021-84886-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Isabell Hubert Lyall ◽

Juhani Järvikivi

Keyword(s):

Personality Traits ◽

Language Processing ◽

Language Comprehension ◽

Pupil Size ◽

Pupil Dilation ◽

Systematic Research ◽

Cognitive Resources ◽

Personality Profiles ◽

Pupillary Responses ◽

Grammatical Errors

AbstractResearch suggests that listeners’ comprehension of spoken language is concurrently affected by linguistic and non-linguistic factors, including individual difference factors. However, there is no systematic research on whether general personality traits affect language processing. We correlated 88 native English-speaking participants’ Big-5 traits with their pupillary responses to spoken sentences that included grammatical errors, "He frequently have burgers for dinner"; semantic anomalies, "Dogs sometimes chase teas"; and statements incongruent with gender stereotyped expectations, such as "I sometimes buy my bras at Hudson's Bay", spoken by a male speaker. Generalized additive mixed models showed that the listener's Openness, Extraversion, Agreeableness, and Neuroticism traits modulated resource allocation to the three different types of unexpected stimuli. No personality trait affected changes in pupil size across the board: less open participants showed greater pupil dilation when processing sentences with grammatical errors; and more introverted listeners showed greater pupil dilation in response to both semantic anomalies and socio-cultural clashes. Our study is the first one demonstrating that personality traits systematically modulate listeners’ online language processing. Our results suggest that individuals with different personality profiles exhibit different patterns of the allocation of cognitive resources during real-time language comprehension.

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Hippocampal gamma-band Synchrony and pupillary responses index memory during visual search

Hippocampus ◽

10.1002/hipo.22702 ◽

2017 ◽

Vol 27 (4) ◽

pp. 425-434 ◽

Cited By ~ 9

Author(s):

Rodrigo Montefusco-Siegmund ◽

Timothy K. Leonard ◽

Kari L. Hoffman

Keyword(s):

Visual Search ◽

Gamma Band ◽

Pupillary Responses

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Is Pupil Activity Associated With the Strength of Memory Signal for Words in a Continuous Recognition Memory Paradigm?

Frontiers in Psychology ◽

10.3389/fpsyg.2021.686183 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jorge Oliveira ◽

Marta Fernandes ◽

Pedro J. Rosa ◽

Pedro Gamito

Keyword(s):

Retention Interval ◽

Recognition Memory ◽

Pupil Size ◽

Time Course ◽

Recognition Performance ◽

Recognition Task ◽

Subjective Feeling ◽

Consistent Finding ◽

Pupillary Responses ◽

Study Test

Research on pupillometry provides an increasing evidence for associations between pupil activity and memory processing. The most consistent finding is related to an increase in pupil size for old items compared with novel items, suggesting that pupil activity is associated with the strength of memory signal. However, the time course of these changes is not completely known, specifically, when items are presented in a running recognition task maximizing interference by requiring the recognition of the most recent items from a sequence of old/new items. The sample comprised 42 healthy participants who performed a visual word recognition task under varying conditions of retention interval. Recognition responses were evaluated using behavioral variables for discrimination accuracy, reaction time, and confidence in recognition decisions. Pupil activity was recorded continuously during the entire experiment. The results suggest a decrease in recognition performance with increasing study-test retention interval. Pupil size decreased across retention intervals, while pupil old/new effects were found only for words recognized at the shortest retention interval. Pupillary responses consisted of a pronounced early pupil constriction at retrieval under longer study-test lags corresponding to weaker memory signals. However, the pupil size was also sensitive to the subjective feeling of familiarity as shown by pupil dilation to false alarms (new items judged as old). These results suggest that the pupil size is related not only to the strength of memory signal but also to subjective familiarity decisions in a continuous recognition memory paradigm.

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RESEARCH OF DIGITAL CAMERA DYNAMIC RANGE ON THE IMAGING PROCESSING BASIS

Devices and Methods of Measurements ◽

10.21122/2220-9506-2017-8-3-271-278 ◽

2017 ◽

Vol 8 (3) ◽

pp. 271-278

Author(s):

M Sutkowski ◽

Ya. N. Saukova

Keyword(s):

Dynamic Range ◽

Digital Camera ◽

Measuring Channel ◽

Blue Color ◽

Lower And Upper Bounds ◽

Color Target ◽

Color Channel ◽

Imaging Processing ◽

Colorimetric Measurements ◽

Target Sets

Digital images provide to determine photometric and colorimetric properties of objects subject to validation all elements of a measuring channel (digital camera, software, display) and solve the problem of their limited dynamic ranges. The aim of the study was to explore the dynamic range of a digital camera for use in photometric and colorimetric measurements.The Laboratory of Photonics at the Institute of Microelectronics and Optoelectronics (Warsaw Technical University, Poland) conducted a comparative experiment to determine the threshold of sensitivity, linearity and range of application the digital camera. Color target sets with certified brightness and chromaticity were created at the terminals and recorded with a digital camera with different exposure times. The authors propose a method to extend the dynamic range of a digital camera for red, green and blue color channel of intensities by pairing the calibration dependencies, and determine the true brightness and color of a point on the object by calculation.Calibration dependencies (triads) of digital camera for red, green and blue color channels intensities were constructed. These dependences allow determining lower and upper bounds of the dynamic range. Each triad has a form of the hysteresis loop. The experiment showed that the accuracy of this method is ± 3–5 %.

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Pupil Response: A Psychophysiological Measure of Fear during Analogue Desensitization,

Perceptual and Motor Skills ◽

10.1177/00315125890693-254 ◽

1989 ◽

Vol 69 (3-2) ◽

pp. 1351-1367

Author(s):

Robert S. Sturgeon ◽

Leslie M. Cooper ◽

Robert J. Howell

Keyword(s):

Pupil Size ◽

Pupillary Response ◽

Pupil Response ◽

Current Technology ◽

Pupillary Responses

15 highly aroused snake phobics individually constructed fear hierarchies by selecting colored photographs of snakes. Subjects either imagined fear scenes based on their photographs or were exposed to duplicate projected slides during desensitization. Pupillary responses of the Slide Group were also recorded before, during, and after desensitization. Fear of snakes was significantly reduced for both groups within five or fewer desensitization sessions. Changes in pupil size of the Slide Group appear to reflect arousal of fear as well as reduction of fear after treatment. Current technology makes pupillary response a viable psychophysiological measure of fear.

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Visual search improvement in hemianopic patients after audio-visual stimulation

Brain ◽

10.1093/brain/awh656 ◽

2005 ◽

Vol 128 (12) ◽

pp. 2830-2842 ◽

Cited By ~ 99

Author(s):

Nadia Bolognini ◽

Fabrizio Rasi ◽

Michela Coccia ◽

Elisabetta Làdavas

Keyword(s):

Visual Search ◽

Visual Stimulation

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Pupillary Responses to Pictures and Descriptions of Sex-Stereotyped Stimuli

Perceptual and Motor Skills ◽

10.2466/pms.1979.49.3.759 ◽

1979 ◽

Vol 49 (3) ◽

pp. 759-764 ◽

Cited By ~ 1

Author(s):

Marsha L. Green ◽

Susan K. Kraus ◽

Ronald G. Green

Keyword(s):

Sex Differences ◽

Pupil Size ◽

College Men ◽

Visual Presentation ◽

Analysis Of Covariance ◽

Verbal Stimuli ◽

Future Studies ◽

Pupillary Responses ◽

Visual Materials ◽

Three Factor

An attempt was made to replicate Hess and Polt's (1960) report of sex differences in pupillary responses to sex-stereotyped pictures. Some methodological refinements were used that seem desirable for future studies. College men and women were either shown or told they would be shown pictures of a semi-nude man, a semi-nude woman, a baby, and a landscape. With resting pupil size as covariate, a three-factor analysis of covariance did not show sex differences in response to visually presented stimuli. Men responded more to verbal than visual mode of presentation and more than women to verbal stimuli. Contrary to previous results, men responded as much or more than women to verbal or visual presentation of baby stimuli. The verbal or anticipatory mode seems to be at least as sensitive as the visual and eliminates problems of control of visual materials.

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