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A prototypical finding of social cognition is that social experiences influence later performance even though those experiences are not introspectively available. Building on social cognition research on implicit attitudes, we evaluate whether ethnic category/attribute pairs influence eye movements during the Implicit Association Test (IAT, Greenwald, McGhee, & Schwartz 1998). Results show that fixation duration predicted implicit attitudes such that when the category/attribute pairs disconfirmed one's implicit negative attitude fixation duration toward that pair increased. The present research provides evidence that eye movements and implicit processes inherent in the IAT are more broadly connected than previously thought.
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Believing Is Seeing: Fixation Duration Predicts Implicit
Negative Attitudes
Maria Laura Mele
, Stefano Federici
, John Lawrence Dennis
1Department of Philosophy, Social & Human Sciences and Education, Perugia, Italy, 2ECONA, Interuniversity Centre for Research on Cognitive Processing in Natural and
Artificial Systems, Sapienza University of Rome, Rome, Italy, 3Department of Psychology, Catholic University, Milan, Italy, 4The Umbra Institute, Perugia, Italy
A prototypical finding of social cognition is that social experiences influence later performance even though those
experiences are not introspectively available. Building on social cognition research on implicit attitudes, we evaluate
whether ethnic category/attribute pairs influence eye movements during the Implicit Association Test (IAT, Greenwald,
McGhee, & Schwartz 1998). Results show that fixation duration predicted implicit attitudes such that when the category/
attribute pairs disconfirmed one’s implicit negative attitude fixation duration toward that pair increased. The present
research provides evidence that eye movements and implicit processes inherent in the IAT are more broadly connected
than previously thought.
Citation: Mele ML, Federici S, Dennis JL (2014) Believing Is Seeing: Fixation Duration Predicts Implicit Negative Attitudes. PLoS ONE 9(8): e105106. doi:10.1371/
Editor: Susana Martinez-Conde, Barrow Neurological Institute, United States of America
Received March 14, 2014; Accepted July 18, 2014; Published August 18, 2014
Copyright: ß2014 Mele et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: The authors confirm that, for approved reasons, there are some access restrictions on the data underlying the findings. Due to ethical policy,
the raw data is only available upon request by third party researchers. Requests should be submitted to Dr. Maria Laura Mele at or Prof.
Stefano Federici at
Funding: The authors have no support or funding to report.
Competing Interests: The authors have declared that no competing interests exist.
* Email:
.These authors contributed equally to this work.
Understanding people’s beliefs, feelings, and attitudes is often
difficult. Reasons for these difficulties vary greatly, but social
desirability [1,2] and the inaccessibility of psychological processes
[3] are two of the most commonly cited reasons. To overcome
these difficulties, implicit techniques, like the Implicit Association
Test (IAT) have been developed [4].
The classic IAT reveals implicit attitudes towards ethnic groups
by asking people to associate one of two ethnic categories (e.g.,
white vs. black) with a bipolar attribute (e.g., good vs. bad). When
the category/attribute pairs are highly associated, response
accuracy increases and association time associate decreases.
Because of its flexibility, robustness, and reliability the IAT has
been widely used to study automatic processes [5].
Previous research has demonstrated that indirect behavioral
measurement methods, like those found in the IAT, e.g., response
times, and eye-tracking techniques are good indicators of implicit
processes [6,7]. Interestingly, the relationship between these two
indirect behavioral measurement methods has only recently been
studied [8–10], and it is still unclear whether eye movements can
provide a predictive model of implicit processes. The present
research attempts to do just that.
The present research is understood within an embodied
cognition theoretical framework. Embodied cognition has repeat-
edly demonstrated that bodily experiences work in concert with
cognitive systems underlying sensory perception, action, emotion,
motivation, and cognitive operations [11,12]. Research has found
that social information processing can occur via bottom-up
processes such that bodily experiences influence high level
cognitive processes or via top-down processes such that cognition
directly influences sensory-motor processes [11,13,14]. We
hypothesize a top-down oculo-sensory-motor embodiment of
social information processing, in line with a growing number of
studies on the perception of social stimuli being associated with
bodily states [14–16].
Visual attention is guided towards unexpected content [17,18]
that taxes cognitive load [19]. In fact, considering this relationship
between visual attention and cognitive load, participants should
show more and/or longer fixations towards visual areas that
disconfirm one’s implicit negative attitude towards the ethnic out-
group, i.e., black/good consistent with research on the salience of
negative attitudes towards out-groups [20,21]. Eye movements
should therefore integrate with belief systems that underlie implicit
attitudes [14,22,23]. Such a finding would allow eye movements to
be considered as a predictive tool for psychological concepts like
attitudes [24].
The present research investigated the relationship between eye
movements and the IAT, an excellent measure of implicit
processing. Eye movements are increasingly being used in different
fields (see e.g., the neuroergonomic studies conducted by Di Stasi
and colleagues [25]) as a bio-behavioral measure for different
physiological and psychological states, such as arousal [26], and
cognitive and attentional load [25–29]. By using an ‘‘off the shelf’’
eye-tracking methodology with a traditional Black-White IAT, two
studies were conducted. Study 1a established that there was a
relationship between eye movements and the IAT while Study 1b
refined the methodology. Together, these two studies suggest that
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fixation duration increased when the visual stimuli disconfirmed
the implicit negative attitude towards the ethnic out-group, i.e.,
black/good. Fixation duration, therefore, was found to predict
implicit attitudes towards the ethnic out-group.
Study 1a
Participants were presented with the IAT while fixation number
and duration were measured. Considering the previous discussion
in the Introduction on the relationship between attention and
unexpected visual information, a positive relationship between
fixation number and/or duration and implicit attitudes, as
measured by the IAT, was expected.
Materials. Eye movements were measured using the ITU
Gaze Tracker software ( that records gaze
position via a webcam that reflects infrared light on the cornea.
Following a nine-point calibration, the ITU device tracks eye
movements with a mean error in visual angle degrees of 1.48
(SD = 0.58) [30].
A Milliseconds Racism IAT (
download/library/IAT) combining the two Caucasian and
African ethnic categories with the good or bad qualitative
attributes was administered online, whereas the OGAMA IAT
was based on the online IAT structure using OGAMA’s Slideshow
Design Module. The IAT was administered twice (the IAT can be
administered more than once with one having little or no impact
on the others [31]). The online IAT was used to calculate implicit
association score whereas the OGAMA IAT was used to measure
and analyze the eye movements performed during the visual
interaction with the IAT stimuli.
Participants. 30 Caucasian (15 female; age M= 34;
SD = 4.31, 80% right-handed; all with 100% visual acuity, 33%
with contact lenses) randomly completed either the online IAT or
the OGAMA IAT first. The study was reviewed and approved by
the Institutional Review Board of the Department of Philosophy,
Social & Human Sciences and Education, University of Perugia.
All participants provided their written informed consent to
participate in this study. No minors/children were enrolled in
this study. The study represented ‘‘no more than minimal risk’’.
Design and Procedure. Sessions were conducted in a quiet
setting and they began with a visual acuity and eye dominance
assessment. Participants were asked to complete either the online
IAT or the OGAMA IAT first. For both participants, semantically
associated words or pictures shown in the middle of the screen to
their corresponding category shown either on the left or the right
via keyboard presses.
Monocular eye movements were sampled by the ITU Gaze
Tracker through an infrared cam mounted on an adjustable
chinrest support that was positioned 60 cm from the screen. Only
during the OGAMA IAT were eye movement fixation number
and duration measured. Fixations were calculated using the
dispersion-type detection algorithm by LC technologies [32]. We
set the maximum distance that a point may vary from the average
fixation point at 20 pixels and the minimum number of samples
that define a fixation at 5 samples. Consecutive fixations within the
maximum distance were merged into one fixation. Two Areas Of
Interest (AOIs) have been defined on a 10246768 LCD monitor: a
rectangular Left AOI, coordinates = P0:(20.7;0.0) P1:(646.3;0.0)
P2:(646.3;268.8) P3:(20.7;268.8), and a Right AOI, coordina-
tes = P0:(644.5;21.9) P1:(1282.7;21.9) P2:(1282.7;268.8)
Participants were asked to associate one of two ethnic categories
(e.g., white vs. black) with a bipolar attribute (e.g., good vs. bad),
both presented on a screen. The OGAMA IAT consisted of three
blocks: one control and two experimental (i.e., initial and
reversed). Each block contained nineteen trials where the screen
position of the ethnic categories (black/white) varied between
blocks while the attributes (bad/good) were fixed for all trails. The
duration of those trials depended on the amount of time
participants’ took to respond to the IAT via key presses. In the
control blocks, the ethnic categories of black and white were
presented either on the left or right while the qualitative attribute
good was always presented on the left and bad was always
presented on the right. Therefore, for the initial blocks, the
category/attribute pair white/good was presented on the left and
black/bad was presented on the right while for the reversed blocks,
black/good was presented on the left and white/bad was
presented on the right (see Table 1 for a category/attribute pair
IAT results revealed that 86% of the participants showed an
automatic preference for white people (33% strong, 33% moderate
and 20% slight preference), whereas 7% showed a slight automatic
preference for black people and 7% had no automatic preference.
A repeated-measures ANOVA on fixation number demonstrat-
ed a main effect of condition (F(2,28) = 4.198, p= .025) and a main
effect of position (left, right) (F(1,29) = 4.677, p= .039). No
significant interaction was found between condition and position
(F(2,28) = 1.033, p..05). A repeated-measures ANOVA on
fixation duration demonstrated no main effect of condition and
position. No significant interaction was found between condition
and position too.
Fixation analysis on category/attribute pair combination within
each experimental block revealed that, for those with an automatic
white people preference, in initial blocks, fixation number for the
pair black/bad (M= 2.93; SD = 5.38 fixation count per AOI) was
significantly lower than white/good (M= 7.8; SD = 14.8 fixation
count per AOI) F(1, 29) = 14.34, p,.05, while for the reversed
blocks no difference between the black/good (M= 4.5; SD = 6.4
fixation count per AOI) and white/bad pairs was found (M= 3.73;
SD = 7.4 fixation count per AOI) F(1, 29) = .237, p..05. Fixation
duration was higher for black/bad (M= 1374.3; SD = 2586.5 ms)
than white/good (M= 810.7; SD = 2556.3 ms) in the initial blocks
F(1, 29) = 7.85, p,.05 and black/good (M= 1442.5;
SD = 2649.1 ms) than white/bad (M= 1212.5; SD = 2791.2 ms)
in the reversed blocks F(1, 29) = 3.38, p,.05.
Multiple linear regression analysis showed that fixation number
and duration were not able to predict automatic preferences
= .029, F(2, 27) = .415, p..05, fixation number b= .118, p.
.05; fixation duration b= .064, p..05, although the intercept
suggested a trend effect (Intercept = .85; t(27) = 8.09; p,.01). A
significant correlation between fixation number and fixation
duration was found for both initial (r= 0.95, p,.05) and reversed
(r= 0.52, p,.05) blocks.
Results suggest that fixation number was significantly different
among both condition and position, although condition did not
influence gaze position on AOIs. Fixation duration did not differ
between blocks. A trend effect for the relationship between fixation
number/duration and implicit attitudes, as measured by the IAT,
was found. Participants fixated more and longer on black/bad
than white/good while also fixating longer on black/good than
white/bad. Results demonstrate that category/attribute pairs that
Believing Is Seeing
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confirm as well as disconfirm one’s implicit attitudes toward an
out-group ethnic category are those that attract visual attention.
Since the visual targets used for each AOI (i.e., the pairs of words
described in fig. 1) never vary in color, contrast, texture, line
shape, size, orientation and background during the trials, we
exclude the possibility that fixation duration differences would
primarily be influenced by visual stimuli, as recently highlighted by
McCamy and colleagues [33]. These results demonstrate that eye
tracking is a good candidate for indirectly measuring implicit
processes [6–10].
Even though automatic preferences are not influenced by
lateralization [4], eye movements can be due to an upper-left gaze
bias [34]. In this study the attributes good/bad were always
presented in fixed positions. Therefore, white/good and black/
Table 1. Categories, attributes and category/attribute pairs and their positions for the Black-White Implicit Association Test (IAT)
used in Study 1b.
Condition Control Control Initial blocks Reversed blocks
Good Left NWhite NGood NWhite/Good NBlack/Good
Good Right NWhite GoodNNWhite/Bad NBlack/Bad
BlackNNBad Black/GoodNWhite/GoodN
The black dots on the table indicate the left or right position of the target on the screen. Good Left corresponds to what was presented in Study 1a.
Figure 1. The screenshots show the 2
2 combination of the ethnic category ‘‘nero’’ (black) and ‘‘bianco’’ (white) with the
qualitative attributes ‘‘buono’’ (good) and ‘‘cattivo’’ (bad) for both good left and good right conditions. For each experimental
condition, a yellow circle represents the effect of position on fixation number whereas the heat map represents the effect of category-attribute
combination on fixation duration.
Believing Is Seeing
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good were only presented on the left while white/bad and black/
bad were only presented on the right. These fixed positions could
have led to an eye movement lateralization effect. Since most
people read from the upper left to the lower right [35] it is difficult
to conclude whether one’s gaze toward the pair was due to the
pair’s salience or reading lateralization. For this reason, the
methodological design behind the IAT cannot exclude or explain
any influence of lateralization on strategies used to explore one’s
visual space. Study 1b was conducted to resolve this problem.
Study 1b
Identical to Study 1a participants completed the Black-White
IAT while fixation number and duration were measured. In Study
1b a between subjects 26262 experimental design (category x
attribute x position) was used to control for a possible eye-
movement lateralization effect. Considering the results from Study
1a, we predicted that category/attribute pairs that confirm/
disconfirm one’s implicit attitudes toward an out-group ethnic
category are those that attract visual attention.
Materials. Identical to Study 1, ITU Gaze Tracking
software, the online IAT and the OGAMA IAT were used.
Participants. 48 Caucasians (29 female; M= 23.5;
SD = 7.35; 85.4% right handed; all with 100% visual acuity,
20% with contact lenses) were randomly assigned to perform
either the online IAT or the OGAMA IAT first. Identical to Study
1, the experiment was reviewed and approved by the Institutional
Review Board of the Department of Philosophy, Social & Human
Sciences and Education, University of Perugia. All participants
provided their written informed consent to participate in this
Design and Procedure. The design and procedure for this
study were identical to Study 1a except that in the initial and
reversed blocks for Study 1b, position on the screen (left/right) of
two ethnic categories (black/white) and qualitative attributes
(good/bad) was manipulated in a 26262 between subjects design.
Two experimental conditions: good left and good right, where the
positive attribute good was fixed on either the left or right were
administered. Good left corresponded to what was presented in
Study 1. See Table 1 for a representation of the category/attribute
Results from the online IAT revealed that 67% of participants
showed an automatic preference for white people (N= 32, of
which 33% strong, 7% moderate and 60% slight preference),
while 33% (N= 16) of the participants had no automatic
preference. No significant difference between the two groups was
found F(1, 45) = 0.49, p..05.
For the good left condition, a repeated-measures ANOVA on
fixation number demonstrated a main effect of condition
(F(2,23) = 10.427, p= .001) and a main effect of position (left,
right) (F(1,23) = 9.120, p= .006). A significant interaction was
found between condition and position (F(2,23) = 5.202, p= .014).
A repeated-measures ANOVA on fixation duration demonstrated
a main effect of condition (F(2,23) = 6.211, p= .007) and position
(left, right) (F(1,24) = 7.096, p= .014). No significant interaction
was found between condition and position.
For the good right condition, a repeated-measures ANOVA on
fixation number demonstrated a main effect of condition
(F(2,20) = 6.464, p= .007). No significant differences were found
for position (left, right) (F(1,21) = 0.041, p..05). No significant
interaction was found between condition and position
(F(2,20) = 2.388, p..05). A repeated-measures ANOVA on
fixation duration demonstrated a main effect of condition
(F(2,20) = 8.699, p= .002) and no effect of position. No significant
interaction was found between condition and position, although
we found a trend of interaction (F(2,20) = 2.936, 0,p,1).
Fixation analysis revealed that for those with an automatic white
people preference, only fixation number was influenced by the left
target position for all block/condition pairs, Wilks lambda = .76,
F(4, 39) = 3.14, p,.05. In the good left condition for the initial
blocks fixation number for the pair white/good (M= 22.9;
SD = 31.4 fixation count per AOI) was significantly higher than
black/bad (M= 8.7; SD = 14.1 fixation count per AOI); F(1,
24) = 4.24, p,.05 while for the reversed blocks, black/good
(M= 10.2; SD = 20.5 fixation count per AOI) was significantly
higher than white/bad (M= .72; SD = 1.54 fixation count per
AOI); F(1, 24) = 5.26, p,.05. In the good right condition reversed
blocks, fixation number for the pair black/bad (M= 14.7; SD =24
fixation count per AOI) was significantly higher than white/good
(M= 4.7; SD = 6.4 fixation count per AOI); F(1, 21) = 4.87, p,
.05. A trend towards significance for the white/bad (M=2;
SD = 5.9 fixation count per AOI) and black/good (M= 9.1
SD = 15.7 fixation count per AOI) pairs of the initial blocks F(1,
21) = 3.58, p= .06 was found.
Fixation duration was higher for black/good (M= 4005.5;
SD = 7687.7 ms) than white/bad (M= 605.9; SD = 2419.3 ms);
F(1, 24) = 4.45, p,.05 in the good left condition reversed blocks,
and for black/good (M= 3344.6; SD = 6780.7 ms) than white/bad
(M= 943.5; SD = 2938.4 ms); F(1, 21) = 4.84, p,.05 in the good
right condition initial blocks. No significant effect of duration was
found for white/good (M= 3641.1; SD = 7191 ms) and black/bad
(M= 1179.6; SD = 3792.4 ms) in the initial blocks of the good left
condition, F(1, 24) = 2.29, p..05) and for black/bad (M= 2974.7;
SD = 3711.3 ms) and white/good (M= 1090.6; SD = 1536.2 ms)
in the reversed blocks of the good right condition, F(1, 21) = 2.32,
A repeated-measure ANOVA between subjects was done. No
difference between the experimental groups was found in the
control blocks for both number and duration fixation. In the initial
blocks a significant effect of position was found between groups for
number of fixation F(1, 21) = 8.584, p= .000. Subjects tended to
gaze for more times towards the white/good pair indifferently
from its position. Moreover, in the initial blocks a significant
interaction between group and position was found for fixation
duration F(1, 21) = 5.244, p= .032. In the reversed blocks a
significant effect of position was found between groups for both
fixation number F(1, 21) = 15.40, p= .001, and duration F(1,
21) = 9.142, p= .006.
Multiple linear regression analysis revealed that fixation number
and duration were significant predictors of IAT scores R
= .106,
F(2, 44) = 2.62, p..05, fixation number b= .80, p,.05; fixation
duration b= -.78, p,.05). A significant correlation between
fixation number and duration was found for both good left
condition (initial blocks, r = 0.87, p,.05; reversed blocks, r = 0.95,
p,.05) and good right condition (initial blocks, r = 0.86, p ,.05;
reversed blocks, r = 0.89, p,.05).
Study 1b was designed to exclude or explain any influence of
lateralization on eye movements. A lateralization effect was found
demonstrating that target position affected fixation number
independently of the IAT. However, when the unexpected
category/attribute pair, i.e., white/bad was presented on the left
and black/good on the right, fixation number for white/bad
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decreased while on for black/good increased. Results demonstrate
that category/attribute pairings that disconfirm our implicit out-
group prejudices (i.e., black/good) are more salient than pairings
that confirm out-group prejudices (i.e., black/bad) or confirm/
disconfirm in-group automatic preferences (i.e., white/good and
white/bad) [20,21]. Study 1b, therefore, revealed that when
lateralization is taken into account only fixation duration is
predictive of implicit attitudes.
General Discussion and Conclusions
This study investigated whether eye movement fixation number
and/or duration could predict implicit attitudes as measured by
the IAT. Embodied cognition theories can be utilized to help
explain the relationship between implicit attitudes as measured by
the IAT and fixation duration. For embodied cognition, eye
movements hold a central role in social cognitive processes via
mechanisms that situate conceptualizations [36]. During the IAT,
participants’ attention – in terms of fixation duration – was focused
on the pair that disconfirmed their implicit negative preference,
i.e., black/good. These findings are in line with embodied
cognition theories in that eye movements should increase in
number and/or duration when psychological attributes are
incompatible with cognitive processes [11,37]. Eye movements
can work in concert with belief systems that underlie implicit
attitudes [14,22,23].
Fixation duration has been found to positively correlate with
task difficulty level [38], thus providing a valid measure to identify
when attentional processing or cognitive load increases. These
findings are also confirmed by recent studies showing that the
difficulty in visual and cognitive processing of the scene modulates
fixation durations [39–41] and microsaccades [33]. Considering
the present research, higher attentional processing or cognitive
load increases would occur when category/attribute pairs
mismatch participant implicit prejudices. Other bio-behavioral
measures, such as pupil dilation, Heart Rate (HR) or Galvanic
Skin Response (GSR) have also been found to be valid measures
for identifying increased processing demands [42] and future
research should therefore take into account the relationship
between these other physiological measures and the IAT to better
understand the relationship between arousal and cognitive load
during the IAT, especially when category/attribute pairs mis-
match participant implicit prejudices.
Because most people read from the upper left to the lower right
[34], Study 1b systematically investigated the effect of lateraliza-
tion on visual information processing. Results demonstrated a
strong relationship between fixation number and lateralization
leaving only fixation duration as a valid predictor of implicit
attitudes. Consistent with previous salience research [20], lateral-
ization was constrained by the strong saliency of the black/good
pair that mismatched one’s implicit prejudice.
Several other questions remain. These include, for example,
whether the relationship between eye movements is consistent
across other versions of the IAT, whether eye-tracking can be
useful to gain insight into how we represent other social cognition
concepts, and whether fixation number and not fixation duration
is consistently influenced by the lateral presentation of those
concepts. Given the importance of implicit representations in our
understanding and evaluation of others and ourselves we see the
use of eye-tracking methodologies as a useful tool to explore these
Author Contributions
Conceived and designed the experiments: SF MLM. Performed the
experiments: MLM. Analyzed the data: MLM SF JLD. Contributed
reagents/materials/analysis tools: MLM SF JLD. Contributed to the
writing of the manuscript: MLM SF JLD. Lead the development of the
original experimental idea: SF. Developed the experimental materials, did
the data collection, did the initial data analysis: MLM. Did the initial data
interpretation: MLM SF. Supervised the final analysis, supervised the final
data interpretation: JLD. Drafted the first manuscript: MLM. Critically
revised the manuscript: SF JLD. Approved the final submitted version:
1. Crowne DP, Marlowe D (1960) A new scale of social desirabi lity independent of
psychopathology. J Consult Psychol 24: 349–354. doi: 10.1037/h0047358
2. Paulhus DL (1991) Measurement and control of response bias. In: Robinson JP,
Shaver PR, Wrightsman LS, editors. Measures of personality and social
psychological attitudes. San Diego, CA: Academic Press. pp.17–59.
3. Nisbett RE, Wilson TD (1977) Telling more than we can know: Verbal reports
on mental processes. Psychol Rev 84: 231–259. doi: 10.1037/0033-
4. Greenwald AG, McGhee DE, Schwartz JLK (1998) Measuring Individual
Differences in Implicit Cognition: The Implicit Association Test. J Pers Soc
Psychol 74: 1464–1480. doi: 10.1037/0022-3514.74.6.1464
5. Wittenbrink B, Schwarz N (2007) Implicit measures of attitudes. New York, NY:
The Guilford Press.
6. Field M, Munafo` MR, Franken IHA (2009) A meta-analytic investigation of the
relationship between attentional bias and subjective craving in substance abuse.
Psychol Bull 135: 589–607. doi: 10.1037/a0015843
7. Friese M, Bargas-Avila J, Hofmann W, Wiers RW (2010) Here’s Looking at
You, Bud: Alcohol-Related Memory Structures Predict Eye Movements for
Social Drinkers With Low Executive Control. Soc Psychol Person 1: 143–151.
doi: 10.1177/1948550609359945
8. Mele ML, Federici S (2012) A psychotechnological review on eye-tracking
systems: Towards user experience. Disabil Rehabil Assist Technol 7: 261–281.
doi: 10.3109/17483107.2011.635326
9. Mele ML, Federici S (2012) Gaze and Eye-Tracking Solutions for Psychological
Research. Cogn Process 13: S261–265. doi: 10.1007/s10339-012-0499-z
10. Mele ML, Federici S (2012) Looking at What One Believes: Investigation of the
Relationship between Eye Movements and Implicit Associations. APPAC
Archives 19: 1.
11. Barsalou LW (1999) Perceptual symbol systems. Behav Brain Sci 22: 577–609.
doi: 10.1017/S0140525X99532149
12. Gallese V (2003) The manifold nature of interpersonal relations: the quest for a
common mechanism. Philos Trans R Soc Lond B Biol Sci 358: 517–528. doi:
13. Casasanto D (2009) Embodiment of abstract concepts: good and bad in right-
and left-handers. J Exp Psychol Gen 138: 351–367. doi: 10.1037/a0015854
14. Niedenthal PM, Barsalou LW, Winkielman P, Krauth-Gruber S, Ric F (2005)
Embodiment in Attitudes, Social Perception, and Emotion. Pers Soc Psychol
Rev 9: 184–211. doi: 10.1207/s15327957pspr0903_1
15. Aarts H, Dijksterhuis A (2002) Category activation effects in judgment and
behaviour: The moderating role of perceived comparability. Br J Soc Psychol
41: 123–138. doi: 10.1348/014466602165090
16. Bargh JA, Chen M, Burrows L (1996) Automaticity of social behavior: Direct
effects of trait construct and stereotype activation on action. J Pers Soc Psychol
71: 230–244. doi: 10.1037//0022-3514.71.2.230
17. Kimmel HD, van Olst EH, Orlebeke JF, Division NATOSA (1979) The
Orienting Reflex in Humans. Hillsdale, NJ: Erlbaum.
18. Campbell BA, Wood G, McBride T (2011) Origins of Orienting and Defensive
Responses: An Evolutionary Perspective. In: Lang PJ, Simons RF, Balaban M,
editors. Attention and Orienting: Sensory and Motivational Processes. New
York, NY: Routledge. pp.41–68.
19. Sweller J, van Merrienboer JG, Paas FWC (1998) Cognitive Architecture and
Instructional Design. Educ Psychol Rev 10: 251–296. doi: 10.1023/
20. Parkhurst D, Law K, Niebur E (2002) Modeling the role of salience in the
allocation of overt visual attention. Vision Res 42: 107–123. doi: 10.1016/
21. Rohmer O, Louvet E (2009) Describing Persons With Disability: Salience of
Disability, Gender, and Ethnicity. Rehabil Psychol 54: 76–82. doi: 10.1037/
22. Amodio DM, Devine PG (2006) Stereotyping and evaluation in implicit race
bias: Evidence for independent constructs and unique effects on behavior. J Pers
Soc Psychol 91: 652–661. doi: 0.1037/0022-3514.91.4.652
Believing Is Seeing
PLOS ONE | 5 August 2014 | Volume 9 | Issue 8 | e105106
23. Neumann R, Strack F (2000) ‘‘Mood contagion’’: The automatic transfer of
mood between persons. J Pers Soc Psychol 79: 211–223. doi: 0.1037//0022-
24. De Houwer J, Moors A (2010) Implicit measures: Similarities and differe nces. In:
Gawronski B, Payne BK, editors. Handbook of Implicit Social Cognition:
Measurement, Theory, and Applications. New York, NY: Guilford Publications.
25. Di Stasi LL, McCamy MB, Macknik SL, Mankin JA, Hooft N, et al. (2014)
Saccadic Eye Movement Metrics Reflect Surgical Residents’ Fatigue. Ann Surg
259: 824–829. doi: 10.1097/sla.0000000000000260
26. Di Stasi LL, Catena A, Can˜as JJ, Macknik SL, Martinez-Conde S (2013)
Saccadic velocity as an arousal index in naturalistic tasks. Neurosci Biobehav
Rev 37: 968–975. doi: 10.1016/j.neubiorev.2013.03.011
27. Di Stasi LL, Cabestrero R, McCamy MB, Rı
´os F, Catena A, et al. (2014)
Intersaccadic drift velocity is sensitive to short-term hypoba ric hypoxia.
Eur J Neurosci 39: 1384–1390. doi: 10.1111/ejn.12482
28. Di Stasi LL, McCamy MB, Catena A, Macknik SL, Can˜as JJ, et al. (2013)
Microsaccade and drift dynamics reflect mental fatigue. Eur J Neurosci 38:
2389–2398. doi: 10.1111/ejn.12248
29. Siegenthaler E, Costela FM, McCamy MB, Di Stasi LL, Otero-Millan J, et al.
(2014) Task difficulty in mental arithmetic affects microsaccadic rates and
magnitudes. Eur J Neurosci 39: 287–294. doi: 10.1111/ejn.12395
30. Johansen SA, Agustin JS, Skovsgaard H, Hansen JP, Tall M (2011) Low Cost vs.
High-End Eye Tracking for Usability Testing. Human Factors in Computing
Systems: CHI 2011. Vancouver, CA: ACM. pp.1177–1182. doi: 10.1145/
31. Greenwald AG, Nosek BA, Banaji MR (2003) Understanding and using the
Implicit Association Test: I. An improved scoring algorithm. J Pers Soc Psychol
85: 197–216. doi: 10.1037/0022-3514.85.2.197
32. Salvucci DD, Goldberg JH (2000) Identifying fixations and saccades in eye-
tracking protocols. Symposium on Eye Tracking Research & Applications:
ETRA 2000. Palm Beach Gardens, FL: ACM. pp.71–78. doi: 10.1145/
33. McCamy MB, Otero-Millan J, Di Stasi LL, Macknik SL, Martinez-Conde S
(2014) Highly informative natural scene regions increase microsaccade
production during visual scanning. The Journal of Neuroscience 34: 2956–
2966. doi: 10.1523/jneurosci.4448-13.2014
34. Durgin FH, Doyle E, Egan L (2008) Upper-left gaze bias reveals competing
search strategies in a reverse Stroop task. Acta Psychol (Amst) 127: 428–448. doi:
35. De Kerckhove D, Lumsden CJ, editors (1988) The Alphabet and the Brain: The
Lateralization of Writing. Berlin, DE: Springer-Verlag.
36. Barsalou LW (2005) Situated Conceptualization. In: Cohen H, Lefebvre C,
editors. Handbook of Categorization in Cognitive Science. Amsterdam, NL:
Elsevier. pp.619–650.
37. Chen M, Bargh JA (1999) Consequences of automatic evaluation: Immediate
behavioral predispositions to approach or avoid the stimulus. Pers Soc Psychol
Bull 25: 215–224. doi: 10.1177/0146167299025002007
38. van Gog T, Kester L, Nievelstein F, Giesbers B, Paas F (2009) Uncovering
cognitive processes: Different techniques that can contribute to cognitive load
research and instruction. Comput Hum Behav 25: 325–331. doi: 10.1016/
39. Henderson JM, Smith TJ (2009) How are eye fixation durations controlled
during scene viewing? Further evidence from a scene onset delay paradigm.
Visual Cognition 17: 1055–1082. doi: 10.1080/13506280802685552
40. Henderson JM, Graham PL (2008) Eye movements during scene viewing:
evidence for mixed control of fixation durations. Psychon Bull Rev 15: 566–573.
doi: 10.3758/PBR.15.3.566
41. Henderson JM, Olejarczyk J, Luke SG, Schmidt J (2014) Eye movement control
during scene viewing: Immediate degradation and enhancement effects of spatial
frequency filtering. Visual Cognition 22: 486–502. doi: 10.1080/
42. Van Gerven PW, Paas F, Van Merrie¨nboer JJ, Schmidt HG (2004) Memory
load and the cognitive pupillary response in aging. Psychophysiology 41: 167–
174. doi: 10.1111/j.1469-8986.2003.00148.x
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... Specifically, followers' fixation durations on the videoed leader's right eye (AoI) was a predictor of the four leader identities (i.e., prototypicality, advancement, entrepreneurship, and impresarioship). Such a finding suggests that the tone or style (i.e., caring) of the videoed leader is matching the attention preference of their followers (Glaholt & Reingold, 2012), and thus influencing the cognitive processing of the message (Mele, Federici, & Dennis, 2014). The dominance of the followers' fixation on the leader's right eye over the left eye in this chapter confirms a left perceptual bias among followers (Williams, Grealy, Kelly, Henderson, & Butler, 2016). ...
This chapter investigated how preexisting ideas (i.e., prototypes and antiprototypes) and what the eyes fixate on (i.e., eye fixations) influence followers’ identification with leaders from another race. A sample of 55 Southeast Asian female participants assessed their ideal leader in terms of prototypes and antiprototype and then viewed a 27-second video of an engaging Caucasian female leader as their eye fixations were tracked. Participants evaluated the videoed leader using the Identity Leadership Inventory, in terms of four leader identities (i.e., prototypicality, advancement, entrepreneurship, and impresarioship). A series of multiregression models identified participants’ age as a negative predictor for all the leader identities. At the same time, the antiprototype of masculinity, the prototypes of sensitivity and dynamism, and the duration of fixations on the right eye predicted at least one leader identity. Such findings build on aspects of intercultural communication relating to the evaluation of global leaders.
... There is a long history of attempts to use eye-tracking tests to infer cognitive processes based on eye movements showing how watchers observe within a scene (Dupont et al., 2014;Mele et al., 2014). To determine the attention pattern of the predictor of landscape preference, this study was extended using an eye-tracking test with Tobii T60XL Eye Tracking equipment to examine the relationship between the visual attention pattern and the perceived tranquillity-the most important predictor affecting rural landscape preferences based on the results of questionnaire survey. ...
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Consensus in preference is a central issue in landscape perception research. Several studies have highlighted the relationships between landscape preference and demographic variables; however, consensus among different countries' observers remains poorly understood. This study was primarily conducted to examine the consensus in factors affecting landscape preferences between potential Chinese and English rural tourists. A questionnaire survey and experimental eye-tracking methods were used. The results showed that, regarding preference for their home countries' rural landscapes, the importance of vegetation is significantly greater for Chinese than for English tourists. Generally, the dominant factors affecting Chinese landscape preference involved progressive enhancement with tranquillity, diversity, traditional characteristics, and maintenance of buildings and human constructions, while English preferences focused on multifaceted maintenance and avoiding the intrusion of building and human constructions. Regarding preferences in favour of Chinese rural landscapes, higher consensus was likely to occur for the most and least preferred landscapes when landscape types were combined, which was even more obvious for the Chinese than the English individuals. When landscape types were separated, there were significant correlations between Chinese and English preferences for natural landscape types, while the considerable difference regarding manmade landscape types could be greater depending on the effects of different factors affecting the preferences for their home countries' landscapes. In addition, a significant effect of observers' attention pattern was presented, suggesting that landscapes providing an easy way to concentrate on smaller interest areas could significantly increase tranquillity and thus increase landscape preference. The present study provides evidence for previous judgement consensus studies and reference for the management or design of countryside landscapes with perceived restorative and visiting potential.
... Despite this, past research examining natural eye movement behavior as a function of higher-level cognitive or personality traits is very limited. Recently, however, researchers have begun to tap this powerhouse of information, and have revealed that eye movements alone can predict traits from the Big Five personality Inventory (Hoppe et al., 2018) as well as other personality characteristics such as optimism (Isaacowitz, 2005;Peters et al., 2016) and negative attitudes (Mele et al., 2014). ...
What is the relationship between creativity, curiosity, and schizotypy? Schizophrenia-spectrum conditions and creativity have been linked to deficits in filtering sensory information, and curiosity is associated with information-seeking. This raises the possibility of a perception-based link between all three concepts. Here, we investigated whether the same individual differences in perceptual encoding explain variance in creativity, curiosity, and schizotypy. We administered an active auditory oddball task and a free viewing eye-tracking paradigm (N=88). Creativity was measured with the figural portion of the Torrance Tests of Creative Thinking (TTCT) and two self-report scales. Schizotypy and curiosity were measured with self-reports. We found that creativity was associated with increased reaction time to the rare tone in the oddball task and was positively associated with the number and duration of fixations in the free viewing task. Schizotypy, on the other hand, showed a negative trend with the number and duration of fixations. Both creativity and curiosity were positively associated with explorative eye movements (unique number of regions visited) and Shannon entropy, while schizotypy was negatively associated with entropy. We further compared saliency maps finding that individuals high versus low in creativity and curiosity, respectively, exhibit differences in where they look. These findings may suggest a perception-based link between creativity and curiosity, but not schizotypy. Implications and limitations of these findings are discussed.
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Global environmental concerns affecting our planet require immediate action. To better understand the psychological dynamics underlying the adoption of pro-environmental behaviors, research increasingly directed its attention to the implicit (unconscious) psychological antecedents (attitudes) of the adoption of sustainable behaviors against climate change. The objective of this systematic review was to examine and summarize the current evidence for the association between the implicit attitudes related to climate change measured through the Implicit Association Test (IAT), and the explicit attitudes, beliefs, and identity toward climate change. Based on PRISMA guidelines, a structured electronic literature search of Google Scholar, PsycInfo, PubMed, Science Direct, PsycArticles, Sociological Abstracts, and Academic Search Complete was conducted. Of the 943 abstracts screened, only 18 studies met the inclusion criteria. Most studies testified independence between implicit and explicit attitudes towards climate change (absence of correlation). Despite this, implicit attitudes still predicted pro-environmental identity, while contradictory results appeared with beliefs. This highlights the urgency of promoting new research to understand on a deeper level dynamics involving implicit attitudes.
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Context: The ecology of the natural and cultural landscape is an important decisive factor for tourists planning trips. The emerging disturbances of a landscape may affect not only the perception of tourist values, but also the health of visitors. Objectives: The aim of the study was to determine the relationships between identification of specific elements of a disturbed natural and cultural landscape and basic physiological reactions in study participants, namely the presence of stress hormones in saliva. The authors also intended to verify a new research method in the field of tourism and landscape assessment. Methods: The study participants were students. Samples of saliva were collected after displaying images. Hormone levels (cortisol, DHEA, testosterone) were determined using immunoenzymatic ELISA kits. Results: The results indicate that all respondents were in agreement as to which factors disturbed the landscapes presented. However, their subjective feelings were not reflected in a statistically significant manner in the physiological and biochemical reactions of their bodies. The authenticity of a landscape seems less important to the participants than expected. The lack of a strong reaction to a disturbed landscape is surprising, especially in the context of tourism, in which natural and cultural assets are some of the major factors affecting purchasing decisions and principal travel motives. Conclusions: This research may be a strong prognostic in the context of sustainable tourism and environment protection. This knowledge may be used by planners and spatial development experts in designing landscapes as well as in assessing the visitors'/tourists' perception of a landscape.
Eyes are communicative. But what happens when eyes are camouflaged? In the present study, while either wearing sunglasses (that camouflaged the eyes) or clear glasses, participants were presented with sexually provocative and neutral images, which they viewed in the presence of another person who they knew was observing their eyes. Unbeknownst to the participants, however, we also surreptitiously monitored and recorded their eye gaze in both conditions. People spontaneously looked more and for longer at the sexually provocative images when their eyes were camouflaged by sunglasses. This finding provides convergent evidence for the proposal that covert attention operates in service of overt social attention, and suggests that decoupling overt and covert attention is much more prevalent than previously assumed. In doing so it also sheds light on the relation between the evolution of human eye morphology and systems of attention.
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The therapeutic advantages of seeing plants have gained increasing consideration in stressful modern societies, however, evidence-based studies on how physiological and emotional states of individuals from different nationalities change when seeing different foliage colors are limited. The study was conducted to explore the physiological and psychological advantages of foliage colors as visual stimuli. The experiment included 40 men from two nations (age: 21.34 ± 3.50 years) and was carried out using five foliage colors including green, light green, green-yellow, green-red and green-white. Participants were exposed to each color for 2 min, when seeing the foliage colors, eye movements and oxy-Hb concentrations were continuously measured. Subjective evaluations of emotions were performed utilizing a semantic differential questionnaire. A significant decrease in oxy-Hb concentration in the frontal lobe was associated with the viewing of green and green-white plants by the Japanese participants and with viewing light green and green-yellow by the Egyptian participants. Participants spent higher fixation numbers and longer durations on these colors. The findings indicate that viewing of these plant colors was positively associated with physiological relaxation. Furthermore, these colors were associated with more positive feelings, such as calmness, comfort and naturalness. Therefore, the presence of these colors in spaces may have positive impacts on relaxation and emotional status.
Objective We conducted a systematic review of peer-reviewed articles aimed at the evaluation of certified flight instructors’ (CFI) performance in a training context and a scoping review of potential research avenues given the previously identified gaps. Background As the demand for pilots will continue to grow significantly in the coming decades, so will the demand for CFIs, and for ways to improve their existing performance. Understanding performance factors of CFIs could benefit their training and help meet the increasing demand for pilots. Method State-of-the-art research on the subject was surveyed via a systematic review of performance factors of CFIs and a scoping review to identify areas where other fields of research could inform CFI performance evaluation. Result Only 20 articles since 1965 have directly assessed performance factors of CFIs. Their focus has mostly been on communication and educational processes. The scoping review brings forward concepts from cognitive psychology and psychophysiology as means of improving the current understanding of CFI situation awareness and task management. Conclusion Very little work has been done on CFI situation awareness and task management. These are the two main domains in which psychophysiological tools could provide a clear understanding of the attentional and decisional processes at play while developing situation awareness in a dynamic environment and quantify the task load affecting it.
This paper investigates whether a frequency-domain model of complexity can accurately predict human visual salience maps. The Sencogi model uses the frequency domain to calculate maps of spatial (i.e., static) and temporal (i.e., dynamic) complexity. This study compares the complexity maps generated by Sencogi to human fixation maps obtained during a visual quality assessment task on static images. This work is the first part of an ongoing multi-step study designed to assess whether fixation maps are an accurate representation of saliency for spatio-temporal scenes. A supporting experiment confirmed that top-down factors, such as scene type, task or emotional states, did not affect human fixation maps. Results show that the Sencogi visual complexity model estimates human eye fixations of images with prediction scores that are significantly above a Chance baseline and is able to compete with a Single Observer baseline. We conclude that the Sencogi visual complexity model is able to predict human fixations in the spatial domain. The next studies will focus on the assessment of Sencogi’s performance predicting visual fixations in the spatio-temporal domain.
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Our eyes are always in motion. Even during periods of relative fixation we produce so-called 'fixational eye movements', which include microsaccades, drift and tremor. Mental fatigue can modulate saccade dynamics, but its effects on microsaccades and drift are unknown. Here we asked human subjects to perform a prolonged and demanding visual search task (a simplified air traffic control task), with two difficulty levels, under both free-viewing and fixation conditions. Saccadic and microsaccadic velocity decreased with time-on-task whereas drift velocity increased, suggesting that ocular instability increases with mental fatigue. Task difficulty did not influence eye movements despite affecting reaction times, performance errors and subjective complexity ratings. We propose that variations in eye movement dynamics with time-on-task are consistent with the activation of the brain's sleep centers in correlation with mental fatigue. Covariation of saccadic and microsaccadic parameters moreover supports the hypothesis of a common generator for microsaccades and saccades. We conclude that changes in fixational and saccadic dynamics can indicate mental fatigue due to time-on-task, irrespective of task complexity. These findings suggest that fixational eye movement dynamics have the potential to signal the nervous system's activation state.
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Classical image statistics, such as contrast, entropy, and the correlation between central and nearby pixel intensities, are thought to guide ocular fixation targeting. However, these statistics are not necessarily task relevant and therefore do not provide a complete picture of the relationship between informativeness and ocular targeting. Moreover, it is not known whether either informativeness or classical image statistics affect microsaccade production; thus, the role of microsaccades in information acquisition is also unknown. The objective quantification of the informativeness of a scene region is a major challenge, because it can vary with both image features and the task of the viewer. Thus, previous definitions of informativeness suffered from subjectivity and inconsistency across studies. Here we developed an objective measure of informativeness based on fixation consistency across human observers, which accounts for both bottom-up and top-down influences in ocular targeting. We then analyzed fixations in more versus less informative image regions in relation to classical statistics. Observers generated more microsaccades on more informative than less informative image regions, and such regions also exhibited low redundancy in their classical statistics. Increased microsaccade production was not explained by increased fixation duration, suggesting that the visual system specifically uses microsaccades to heighten information acquisition from informative regions.
This book is a consequence of the suggestion that a major key to­ ward understanding cognition in any advanced culture is to be found in the relationships between processing orthographies, lan­ guage, and thought. In this book, the contributors attempt to take only the first step, namely to ascertain that there are reliable con­ stancies among the interactions between a given type of writing and specific brain processes. And, among the possible brain processes that could be investigated, only one apparently simple issue is being explored: namely, whether the lateralization of reading and writing to the right in fully phonemic alphabets is the result of formalized but essentially random occurrences, or whether some physiological determinants are at play. The original project was much more complicated. It began with Derrick de Kerckhove's attempt to establish a connection between the rise of the alphabetic culture in Athens and the development of a theatrical tradition in that city from around the end of the 6th century B. c. to the Roman conquest. The underlying assumption, first proposed in a conversation with Marshall McLuhan, was that the Greek alphabet was responsible for a fundamental change in the psychology of the Athenians and that the creation of the great tragedies of Greek theatre was a kind of cultural response to a con­ dition of deep psychological crisis.
In reporting Implicit Association Test (IAT) results, researchers have most often used scoring conventions described in the first publication of the IAT (A. G. Greenwald, D. E. McGhee, & J. L. K. Schwartz, 1998). Demonstration IATs available on the Internet have produced large data sets that were used in the current article to evaluate alternative scoring procedures. Candidate new algorithms were examined in terms of their (a) correlations with parallel self-report measures, (b) resistance to an artifact associated with speed of responding, (c) internal consistency, (d) sensitivity to known influences on IAT measures, and (e) resistance to known procedural influences. The best-performing measure incorporates data from the IAT's practice trials, uses a metric that is calibrated by each respondent's latency variability, and includes a latency penalty for errors. This new algorithm strongly outperforms the earlier (conventional) procedure.
What controls how long the eyes remain fixated during scene perception? We investigated whether fixation durations are under the immediate control of the quality of the current scene image. Subjects freely viewed photographs of scenes in preparation for a later memory test while their eye movements were recorded. Using the saccade-contingent display change method, scenes were degraded (Experiment 1) or enhanced (Experiment 2) via blurring (low-pass filtering) during predefined saccades. Results showed that fixation durations immediately after a display change were influenced by the degree of blur, with a monotonic relationship between degree of blur and fixation duration. The results also demonstrated that fixation durations can be both increased and decreased by changes in the degree of blur. The results suggest that fixation durations in scene viewing are influenced by the ease of processing of the image currently in view. The results are consistent with models of saccade generation in scenes in which moment-to-moment difficulty in visual and cognitive processing modulates fixation durations.
This chapter develops two themes about the conceptual system: modal simulations underlie conceptual processing, and conceptual representations are situated. The construct of situated conceptualization-a multimodal simulation that supports one specific course of situated action with a particular category instance-integrates these themes. A given concept produces many different situated conceptualizations, each tailored to different instances in different settings. A situated conceptualization creates the experience of "being there" with a category instance in a setting via integrated simulations of objects, settings, actions, and introspections. On recognizing a familiar type of instance, an entrenched situated conceptualization associated with it becomes active, which provides relevant inferences via pattern completion. The chapter reviews supporting empirical evidence from cognitive psychology, social psychology, and cognitive neuroscience.
Hypoxia, defined as decreased availability of oxygen in the body's tissues, can lead to dyspnea, rapid pulse, syncope, visual dysfunction, mental disturbances such as delirium or euphoria, and even death. It is considered to be one of the most serious hazards during flight. Thus, early and objective detection of the physiological effects of hypoxia is critical to prevent catastrophes in civil and military aviation. The few studies that have addressed the effects of hypoxia on objective oculomotor metrics have had inconsistent results, however. Thus, the question of whether hypoxia modulates eye movement behavior remains open. Here we examined the effects of short-term hypobaric hypoxia on the velocity of saccadic eye movements and intersaccadic drift of Spanish Air Force pilots and flight engineers, compared with a control group that did not experience hypoxia. Saccadic velocity decreased with time-on-duty in both groups, in correlation with subjective fatigue. Intersaccadic drift velocity increased in the hypoxia group only, suggesting that acute hypoxia diminishes eye stability, independently of fatigue. Our results suggest that intersaccadic drift velocity could serve as a biomarker of acute hypoxia. These findings may also contribute to our understanding of the relationship between hypoxia episodes and central nervous system impairments.
Microsaccades are involuntary, small-magnitude saccadic eye movements that occur during attempted visual fixation. Recent research has found that attention can modulate microsaccade dynamics, but few studies have addressed the effects of task difficulty on microsaccade parameters, and those have obtained contradictory results. Further, no study to date has investigated the influence of task difficulty on microsaccade production during the performance of non-visual tasks. Thus, the effects of task difficulty on microsaccades, isolated from sensory modality, remain unclear. Here we investigated the effects of task difficulty on microsaccades during the performance of a non-visual, mental arithmetic task with two levels of complexity. We found that microsaccade rates decreased and microsaccade magnitudes increased with increased task difficulty. We propose that changes in microsaccade rates and magnitudes with task difficulty are mediated by the effects of varying attentional inputs on the rostral superior colliculus activity map.