Pupillometry Research Papers - Academia.edu (original) (raw)

In neuronal recording studies on anesthetized animals, reliable measures for the transitional moment of consciousness are frequently required. Previous findings suggest that pupil fluctuations reflect the neuronal states during quiet wakefulness, whose correlation was unknown for the anesthetized condition. Here, we investigated the pupillary changes under isoflurane anesthesia simultaneously with the electroencephalogram (EEG) and electromyogram (EMG). The pupil was tracked by using a region-based active contour model. The dose was given to the animal in a stepwise increasing mode (simulating induction of anesthesia) or in a stepwise decreasing mode (simulating emergence of anesthesia). We found that the quickly widening pupil action (mydriasis) characterizes the transitional state in anesthesia. Mydriasis occurred only in the light dose in the emergence phase, and the events suggest that recording such pupil changes may offer a noncontact monitoring tool for indexing the transitional state of the brain, particularly when a lower threshold dose is applied.

- by
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- EEG, Pupillometry, Anesthesia
- by Alice Carter
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- Developmental Psychology, Visual attention, Autism Spectrum Disorders, Attention

This article presents two studies that deepen the theme of how soundtracks shape our interpretation of audiovisuals. Embracing a multivariate perspective, Study 1 (N = 118) demonstrated, through an online between-subjects experiment, that two different music scores (melancholic vs. anxious) deeply affected the interpretations of an unknown movie scene in terms of empathy felt toward the main character, impressions of his personality, plot anticipations, and perception of the environment of the scene. With the melancholic music, participants felt empathy toward the character, viewing him as more agreeable and introverted, more oriented to memories than to decisions, while perceiving the environment as cozier. An almost opposite pattern emerged with the anxious music. In Study 2 (N = 92), we replicated the experiment in our lab but with the addition of eye-tracking and pupillometric measurements. Results of Study 1 were largely replicated; moreover, we proved that the anxious score, by increasing the participants' vigilance and state of alert (wider pupil dilation), favored greater attention to minor details, as in the case of another character who was very hard to be noticed (more time spent on his figure). Results highlight the pervasive nature of the influence of music within the process of interpretation of visual scenes.

- by Alessandro Ansani
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- Psychology, Cognitive Psychology, Eye tracking, Environmental Psychology

Методичні рекомендації, що мають на меті поліпшення роботи з групами і колективами в системі освіти, допоможуть їх користувачам краще оволодіти методиками й технологіями оптимізації групової взаємодії, соціально-психологічного клімату в групах, розвитку творчого потенціалу групи. У них представлено багатий практичний інструментарій: методи роботи з груповою ди-намікою, технології командотворення, методики рольової взаємодії і роботи з новоствореними групами, засоби подолання професійного вигорання та запобі-гання цьому явищу, методи міжгрупової взаємодії та інші практичні напрацюван-ня. Опис інструментарію супроводжується численними прикладами групової роботи з власного досвіду авторів та досвіду, запозиченого з літературних джерел. Для практичних психологів, педагогів і керівників системи освіти, а також усіх, хто цікавиться проблемами малих груп і методами практичної роботи з ними, від кого залежить ефективність роботи малих груп, що беруть участь в освітньому процесі.

- by Halyna Tsyhanenko and +1
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- Teacher Training, Pupillometry, Burnout, Group Identity

- by Francesca D'Errico
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- Psychology, Cognitive Psychology, Eye tracking, Environmental Psychology

The objective of this work is to monitor the effects
of light on pupil size considering different type
of sources and retinal images in order to isolate the
effect of dimension and spectra distribution of the
emitted radiations. A pupillometric system has been
built, constituted by an infrared illuminator and a
high-resolution camera, in order to acquire eye images
and get pupil dimensions through an ad hoc
designed software. From the fi rst tests differences
on pupil size due to different spectrum and shape
of sources has been founded even at equal luminance
of the source. This study, as a basic research
on measurements of photobiological effects of light,
would improve the knowledge of human visual system
especially for applications in lighting design
like road lighting or where psychophysical effects
of light are important issues.
The activity described is a part of the EMRP
project ENG05: Metrology for solid state lighting.
The EMRP is jointly funded by the EMRP participating
countries within EURAMET and the European
Union.”

- by Laura Rossi and +1
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- Pupillometry, LED Lighting, Pupillary light reflex

Clinical evaluation of pupils is considered as an essential part of neurological examination. The pu-pillary response to light is controlled by the autonomic nervous system. Numerous factors affect pupils dynamics, like e.g. luminance, visual field area, pain, drug administration, age, the functional integrity of anatomical structures involved, e.t.c. Moreover, pupillometry card method and examina-tion of pupil reaction with the use of a penlight is subjective to a lot of bias. Portable infrared pupil-lometry allows a more objective and detail evaluation of pupil’s dynamics. That’s why it has al-ready found applications in various clinical areas, like e.g. neurology, psychology, ophthalmology, endocrinology, anesthesia, pain management, intensive care, emergency medicine. This review fo-cuses on physiology of pupil’s dynamics and on applications of infrared pupillometry in periopera-tive setting

- by Theodoros Aslanidis
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- Neuroscience, Pupillometry, ICU, Glasgow Coma Scale

Many nonvisual functions are regulated by light through a photore-ceptive system involving melanopsin-expressing retinal ganglion cells that are maximally sensitive to blue light. Several studies have suggested that the ability of light to modulate circadian entrainment and to induce acute effects on melato-nin secretion, subjective alertness, and gene expression decreases during aging, particularly for blue light. This could contribute to the documented changes in sleep and circadian regulatory processes with aging. However, age-related modification in the impact of light on steady-state pupil constriction, which regulates the amount of light reaching the retina, is not demonstrated. We measured pupil size in 16 young (22.8 ± 4 years) and 14 older (61 ± 4.4 years) healthy subjects during 45-second exposures to blue (480 nm) and green (550 nm) mono-chromatic lights at low (7 × 10 12 photons/cm 2 /s), medium (3 × 10 13 photons/cm 2 /s), and high (10 14 photons/cm 2 /s) irradiance levels. Results showed that young subjects had consistently larger pupils than older subjects for dark adaptation and during all light exposures. Steady-state pupil constriction was greater under blue than green light exposure in both age groups and increased with increasing irradiance. Surprisingly, when expressed in relation to baseline pupil size, no significant age-related differences were observed in pupil constriction. The observed reduction in pupil size in older individuals, both in darkness and during light exposure, may reduce retinal illumination and consequently affect non-visual responses to light. The absence of a significant difference between age groups for relative steady-state pupil constriction suggests that other factors such as tonic, sympathetic control of pupil dilation, rather than light sensitivity per se, account for the observed age difference in pupil size regulation. Compared to other nonvisual functions, the light sensitivity of steady-state pupil constriction appears to remain relatively intact and is not profoundly altered by age.

- by Véronique Daneault and +2
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- Aging, Pupillometry, Light

What we already know a) Pain assessment in anesthetized children is challenging and currently used methods are not specific. b) Pupillometry has already shown to be interesting and the pupillary pain index (PPI) in anesthetized adults shows promising results. What new information this study ads. c) PPI can be a useful tool for non-invasive nociceptive assessments, in anesthetized, pediatric patients. Background: Inadequate treatment of pain has

- by Fortune Journals
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- Pupillometry, Children

Choice viewing behavior when looking at affective scenes was assessed to examine differences due to hedonic content and gender by monitoring eye movements in a selective looking paradigm. On each trial, participants viewed a pair of pictures that included a neutral picture together with an affective scene depicting either contamination, mutilation, threat, food, nude males, or nude females. The duration of time that gaze was directed to each picture in the pair was determined from eye fixations. Results indicated that viewing choices varied with both hedonic content and gender. Initially, gaze duration for both men and women was heightened when viewing all affective contents, but was subsequently followed by significant avoidance of scenes depicting contamination or nude males. Gender differences were most pronounced when viewing pictures of nude females, with men continuing to devote longer gaze time to pictures of nude females throughout viewing, whereas women avoided scenes of nude people, whether male or female, later in the viewing interval. For women, reported disgust of sexual activity was also inversely related to gaze duration for nude scenes. Taken together, selective looking as indexed by eye movements reveals differential perceptual intake as a function of specific content, gender, and individual differences.

- by Vincent D . Costa
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- Psychology, Cognitive Psychology, Personality Psychology, Emotion

Motor imagery (MI; mental simulation of actions) shares certain mental representations and processes with executed movement (ME). This neurocognitive overlap between MI and ME may explain why the systematic use of MI improves skilled performance in numerous domains. Unfortunately, the attentional mechanisms underlying MI remain unresolved. Therefore, the present studies investigated the role of attentional effort (as measured by pupil dilation) in MI. We evaluated the effects of movement
complexity and speed on expert pianists' pupil dilation as
they physically executed and used MI to perform easy/complex and slow/fast music phrases. Results revealed that easy movements required similar levels of attentional effort during MI and ME. However, during complex movements performed at a fast speed, the correspondence between execution and imagery of
movement was disrupted.

- by Helen O'Shea, PhD, MPsychSc
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- Attention, Pupillometry, Motor Cognition, Motor Imagery
- by Eugen Fischer
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- Experimental philosophy, Eye tracking, Intuition, Eye Tracking (in reading)

Research 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. Comprehending language is an impressive feat: understand a word in a fifth of a second 1 , and surprisal at an unexpected word in an utterance can be detected in ERP signatures as early as 250 ms after its onset. Given that the duration of a single syllable is roughly 200ms 1,2 , this means that comprehension and surprisal often occur before the offset of the relevant word. In this short amount of time, listeners complete a number of tasks, including identifying the sounds, recognizing the word form, retrieving lexical information associated with it, and integrating it into the prior context 3,4. Recent research suggests that in this process, both linguistic and extra-linguistic context-for example visual affordances, world knowledge, and listener and speaker properties-are taken into consideration in parallel with lexical, syntactic, and semantic information 5-7. For example, violations of what speakers know about the world disrupt the flow of comprehension as rapidly as a semantically ill-fitting word: For example, semantic violations (such as "Dutch trains are sour") and violations of world knowledge (such as "Dutch trains are white" when they are, in fact, yellow) have been shown to prompt an identical N400 signature in listeners 6. Language comprehension has further been shown to be influenced by the listener's working memory capacity (WMC), which modulates initial attention-related processes, and comprehension effort more generally 8. Importantly, recent research suggests that language processing is affected by an interplay of individual differences related to both the speaker and the listener, especially the speaker's perceived or inferred identity. Van Berkum and colleagues 7 showed an N400 ERP signature, starting around 200-300 ms after the onset of the critical word ("teddy bear") when it did not fit with the speakers' perceived identity, for example, when participants heard an adult male say "I cannot sleep without my teddy bear in my arms, " even though the sentence is in itself well-formed. Similar N400 ERPs were also elicited by statements that did not align with the speaker's perceived gender or socioeconomic status. They also showed that such statements, inconsistent with inferences about the speaker, elicited the same type of response as semantic violations, such as "You wash your hands with horse and water, " as opposed to "You wash your hands with soap and water. " Importantly, Van den Brink and colleagues 9 showed that this effect was modulated by the listeners' ability to empathize: high empathizers showed a larger N400 effect than low empathizers, and the size of the N400 amplitude was significantly correlated with the OPEN

- by Juhani Järvikivi
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- Social Psychology, Pragmatics, Psycholinguistics, Pupillometry

During recognition memory tests participants’ pupils dilate more when they view old items compared to novel items. We sought to replicate this “pupil old/new effect” and to determine its relationship to participants’ responses. We compared changes in pupil size during recognition when participants were given standard recognition memory instructions, instructions to feign amnesia and instructions to report all items as new. Participants’ pupils dilated more to old items compared to new items under all three instruction conditions. This finding suggests that the increase in pupil size that occurs when participants encounter previously studied items is not under conscious control. Given that pupil size can be reliably and simply measured, the pupil old/new effect may have potential in clinical settings as a means for determining whether patients are feigning memory loss.

This study introduces a method ideally suited for investigating toddlers’ ability to detect mispronunciations in lexical representations: pupillometry. Previous research has established that the magnitude of pupil dilation reflects differing levels of cognitive effort. Building on those findings, we use pupil dilation to study the level of detail encoded in lexical representations with 30-month-old children whose lexicons allow for a featurally balanced stimulus set. In each trial, we present a picture followed by a corresponding auditory label. By systematically manipulating the number of feature changes in the onset of the label (e.g., baby ∼ daby ∼ faby ∼ shaby), we tested whether featural distance predicts the degree of pupil dilation. Our findings support the existence of a relationship between featural distance and pupil dilation. First, mispronounced words are associated with a larger degree of dilation than correct forms. Second, words that deviate more from the correct form are related to a larger dilation than words that deviate less. This pattern indicates that toddlers are sensitive to the degree of mispronunciation, and as such it corroborates previous work that found word recognition modulated by sub-segmental detail and by the degree of mismatch. Thus, we establish that pupillometry provides a viable alternative to paradigms that require overt behavioral response in increasing our understanding of the development of lexical representations.

- by Katalin Tamási and +2
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- Eye tracking, Pupillometry, Phonological development, Lexical Representation and Processing
- by Manuela M Marin
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- Music Psychology, Pupillometry
- by Marco Pedrotti
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- Eye tracking, Motorcycles, Pupillometry, Simulation
- by Eugen Fischer
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- Psychology, Cognitive Science, Philosophy, Experimental philosophy

This article presents two studies that deepen the theme of how soundtracks shape our interpretation of audiovisuals. Embracing a multivariate perspective, Study 1 (N = 118) demonstrated, through an online between-subjects experiment, that two different music scores (melancholic vs. anxious) deeply affected the interpretations of an unknown movie scene in terms of empathy felt toward the main character, impressions of his personality, plot anticipations, and perception of the environment of the scene. With the melancholic music, participants felt empathy toward the character, viewing him as more agreeable and introverted, more oriented to memories than to decisions, while perceiving the environment as cozier. An almost opposite pattern emerged with the anxious music. In Study 2 (N = 92), we replicated the experiment in our lab but with the addition of eye-tracking and pupillometric measurements. Results of Study 1 were largely replicated; moreover, we proved that the anxious score, by increasing the participants’ vigilance and state of alert (wider pupil dilation), favored greater attention to minor details, as in the case of another character who was very hard to be noticed (more time spent on his figure). Results highlight the pervasive nature of the influence of music within the process of interpretation of visual scenes.

- by Francesca D'Errico
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- Psychology, Cognitive Psychology, Eye tracking, Environmental Psychology

Se presenta un prototipo de prótesis pupilar basada Sen Cristal Líquido (CL). Esta prótesis trabaja como un sensor-actuador. Controla la luz que incide en la retina, con ello protegiendo a la misma de la cantidad de luz que incida en ella. La prótesis se insertará en la cámara anterior del ojo humano y será controlada electrónicamente utilizando un sensor óptico.

- by Arturo Gamino Carranza
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- Pupillometry

The food sensory science community has recently shown an increasing interest towards the
measurement of emotions induced by product consumption. In this paper, we propose a
standard method to objectively and quantitatively explore emotions in tasting situations
through measurement and analysis of pupil diameter. Pupillometry is a well-known method
for investigating cognitive load and emotional effects. However, since a standard method to
analyze pupil response data is lacking, we provide here a guided methodology, from data
acquisition to data processing. An example of an application is also provided. The advantages
and major drawbacks of this method are discussed.

- by Thierry Baccino
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- Pupillometry

As long as the pilot is a key agent in charge of the flight, the definition of metrics able to predict his performance is a great challenge. Currently, online assessment of the aircrew performance relies on the aircraft state vector analysis. More recent approaches propose to refine this performance measurement by taking into account the pilots-aircraft interactions state vector (e.g. the pilot's actions on his user interface) or the pilot's physiological state vector. In this latter perspective, this preliminary study proposes to assess the benefits of using a standalone eye tracker in a light aircraft in real conditions. In spite of a sensitivity to light conditions and a definition of areas of interest limited to a part of the cockpit, the eye tracker has provided interesting behavioural (fixations) and physiological (pupillometry) measures in nominal (from takeoff to landing) and degraded (provoke a simulated engine failure and plane down toward the airfield) conditions. The pilots spent less time glancing at the instruments, and focused less on instruments in the degraded condition. Moreover, the pupil size varied with the flight phases in the degraded condition, which reflected the variations of stress and attention levels. These encouraging results open promising perspective to online assess pilot performance through physiological vector.

- by Mickael Causse
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- Pupillometry, Piloting, Eye tracker, Psychological Stress
- by Pedro J Rosa and +1
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- Psychology, Psychophysiology, Pupillometry, Skin conductance

Psycholinguistic methods hold great promise for experimental philosophy. Many philosophical thought experiments and arguments proceed from verbal descriptions of possible cases. Many relevant intuitions and conclusions are driven by spontaneous inferences about what else must also be true in the cases described. Such inferences are continually made in language comprehension and production. This chapter explains how methods from psycholinguistics can be employed to study such routine automatic inferences, with a view to assessing intuitions and reconstructing arguments. We demonstrate how plausibility ratings, pupillometry, and reading time measurements can be used to examine hypotheses about automatic inferences in speech and text comprehension. Two experiments on inferences from polysemous (perception-)verbs provide evidence of a potentially consequential ‘salience bias’. Findings help assess intuitions about unusual cases and analyse a philosophical paradox (‘argument from hallucination’). The paper thus illustrates how we can adapt psycholinguistic methods for philosophical purposes and demonstrates the methods’ philosophical usefulness.

- by Eugen Fischer
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- Psychology, Experimental philosophy, Eye tracking, Intuition

Assessing effort in speech comprehension for hearing-impaired (HI) listeners is important, as effortful processing of speech can limit their hearing rehabilitation. We examined the measure of pupil dilation in its capacity to accommodate the het-erogeneity that is present within clinical populations by studying lexical access in users with sensorineural hearing loss, who perceive speech via cochlear implants (CIs). We compared the pupillary responses of 15 experienced CI users and 14 age-matched normal-hearing (NH) controls during auditory lexical decision. A growth curve analysis was applied to compare the responses between the groups. NH listeners showed a coherent pattern of pupil dilation that reflects the task demands of the experimental manipulation and a homogenous time course of dilation. CI listeners showed more variability in the morphology of pupil dilation curves, potentially reflecting variable sources of effort across individuals. In follow-up analyses, we examined how speech perception, a task that relies on multiple stages of perceptual analyses, poses multiple sources of increased effort for HI listeners, wherefore we might not be measuring the same source of effort for HI as for NH listeners. We argue that interindividual variability among HI listeners can be clinically meaningful in attesting not only the magnitude but also the locus of increased effort. The understanding of individual variations in effort requires experimental paradigms that (a) differentiate the task demands during speech comprehension, (b) capture pupil dilation in its time course per individual listeners, and (c) investigate the range of individual variability present within clinical and NH populations.

- by anita wagner and +1
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- Eye tracking, Speech perception, Pupillometry, Individual Differences

This article proposes a method based on wavelet transform and neural networks for relating pupillary behavior to psychological stress. The proposed method was tested by recording pupil diameter and electrodermal activity during a simulated driving task. Self-report measures were also collected. Participants performed a baseline run with the driving task only, followed by three stress runs where they were required to perform the driving task along with sound alerts, the presence of two human evaluators, and both. Self-reports and pupil diameter successfully indexed stress manipulation, and significant correlations were found between these measures. However, electrodermal activity did not vary accordingly. After training, the four-way parallel neural network classifier could guess whether a given unknown pupil diameter signal came from one of the four experimental trials with 79.2% precision. The present study shows that pupil diameter signal has good discriminating power for stress detection.

- by Marco Pedrotti and +2
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- Classification (Machine Learning), Stress physiology, Stress, Neural Networks

From a young age, children understand and enforce moral norms, which are aimed at preserving the rights and welfare of others. Children also distinguish moral norms from other types of norms such as conventional norms, which serve to ensure coordination within social groups or institutions. However, far less is known about the mechanisms driving this differentiation. This article investigates the role of internal arousal in distinguishing moral from conventional norms. In a between-subjects design, 3-year-olds (n = 32), 4-year-olds (n = 34), and undergraduate students (n = 64) watched a video of either a moral norm violation (e.g., destroying another person’s artwork) or a conventional norm violation (e.g., playing a game wrong). Participants of all age groups showed differential physiological arousal (pupil dilation) to moral and conventional norm violations. Participants of all age groups also attended significantly more to the victim of the moral transgression than the bystander in the conventional transgression. Further, this differential attention to the victim/bystander positively correlated with the change in participants’ phasic pupil dilation to the norm violation. This is the first evidence that differences in internal arousal co-occur with (and possibly contribute to) the distinction that even young children draw between moral and conventional norms.

- by Meltem Yucel
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- Developmental Psychology, Moral Psychology, Evolution of Morality, Moral Development

Many philosophical thought experiments and arguments involve unusual cases. We present empirical reasons to doubt the reliability of intuitive judgments and conclusions about such cases. Inferences and intuitions prompted by verbal case descriptions are influenced by routine comprehension processes which invoke stereotypes. We build on psycholinguistic findings to determine conditions under which the stereotype associated with the most salient sense of a word predictably supports inappropriate inferences from descriptions of unusual (stereotype-divergent) cases. We conduct an experiment that combines plausibility ratings with pupillometry to document this 'salience bias': We find that under certain conditions, competent speakers automatically make stereotypical inferences they know to be inappropriate.

- by Eugen Fischer
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- Experimental philosophy, Natural Language Processing, Stereotypes, Intuition

This study shows for the first time that mispronunciation detection in 24-month-old mono-and bilingual children can be assessed using pupil data from a preferential looking study. Mispronounced words (specifically, consonant, vowel and tone changes) resulted in larger degrees of pupil dilation for bilingual children than correctly produced words, whereas monolingual children's pupillary responses provided no evidence of sensitivity to mispronunciations. Between-group comparisons revealed that pupil dilation of bilingual children in response to correct labels was lower than monolingual children. Overall performance reversed with consonant-changed labels, but was comparable with vowel-and tone-changed labels. Taking degree of pupil dilation as a proxy of cognitive effort, we argue that in comparison to monolinguals, bilingual children seem to require fewer resources for processing correct labels, while if anything, more resources for processing mispronounced labels in order to activate the corresponding lexical entry. This finding – converging on past research showing enhanced bilingual sensitivity to detect mismatch and mispronunciations [1] – further supports the notion that certain aspects of bilingual early words are represented in greater detail than those of monolingual words.

- by Katalin Tamási
- •
- Language Acquisition, Eye tracking, Pupillometry, Bilingualism

The use of eye movements is a usual method of measuring attentional and emotional response in laboratory. However, when it comes to clinical practice, it is seldom applied. Two studies were conducted to examine whether extraocular and intraocular movements can be used as indices of attentional bias and autonomic activation. In the first study, a free-viewing task, combined with subliminal exposure, showed that high-fear individuals tend to orient more their attention toward the visual space where threat-stimuli (snakes) were presented. The findings suggest a reflexive overt attentional orienting bias for subliminal snakes in comparison with subliminal control stimuli. The differentiation between participants with high and low fear of snakes suggested that a disposition to fear snakes affects the initial ocular saccades. In the second study, participants were instructed to discriminate a sign that was randomly displayed at the center of the display while subliminal images were peripherally presented. The results revealed larger pupil dilation for threatening stimuli subliminally presented; again, high-fear individuals showed larger pupillary dilations, independently of the stimulus category. Our results are in line with the assumption that a predisposition to fear is relevant for extraocular and intraocular movements when exposed to threat stimuli. These findings suggest that eye measurements, combined with subliminal exposure techniques, could be a reliable and nonintrusive aid tool to be used for the assessment and treatment of fear and phobias

- by Pedro J Rosa and +2
- •
- Eye tracking, Fear, Pupillometry, Eye Movements (Psychology)
- by Simone Benedetto
- •
- Psychology, Eye tracking, Motorcycles, Pupillometry

Studying memory in infants can be challenging, as they cannot express their subjective recollection verbally. In this study we use a novel method with which we can assess episodic recognition memory through pupillometry, using identical procedures and stimuli for infants and adults. In three experiments of 4- and 7-month old infants, and adults we show that the adult pupillary response is larger to previously seen than to never seen items (old/new effect). Pupil dilations index subjective memory experience in adults, producing distinct pupil dilations to items judged as remembered, familiar, and new, regardless of actual previous exposure (Experiment 1). Seven-month-old infants’ demonstrate a clear pupillary old/new effect, very similar to that of adults’ (Experiment 2), whereas 4-month-olds do not demonstrate such an effect (Experiment 3). Our findings suggest that the mnemonic mechanisms that serve infants' and adults' episodic recognition memory are more similar than previously asserted: they are not fully developed at 4 months of age but that there is contiguity in human episodic memory development from 7 months of age.

- by Kahl Hellmer
- •
- Developmental Psychology, Eye tracking, Pupillometry, Episodic Memory

—Dynamic changes of pupil dilation represent an established indicator of cognitive load in cognitive sciences Exploitation of these insights regarding pupil dilation as an indicator of cog-nitive load for attention-aware Information and Communication (ICT) systems has been impeded due to restrictions of pupil analysis to a posteriori processing and exclusion of disturbing environmental factors. To overcome these issues, this paper proposes an algorithm based on Hoeks's pupil response model, enabling online analysis of pupil dilation for the dynamic interpretation of cognitive load as an input for interactive, attention-aware systems, which outperforms state-of-the-art approaches regarding complexity, accuracy, flexibility and computation time. Beyond mathematical pupil modeling, this paper identifies Environment Illumination compensation (IC), Blink Compensation (BC), Reference Baseline computation (RB) and Onset/Offset detection (OO) as crucial fields of research for the transfer of pupillometry from the laboratory into real-life application scenarios.

- by Benedikt Gollan
- •
- Visual attention, Attention, Pupillometry

This study investigated the relation between word surprisal and pupil dilation during reading. Participants' eye movements and pupil size were recorded while they read single sentences. Surprisal values for each word in the sentence stimuli were estimated by both a recurrent neural network and a phrase-structure grammar. Higher surprisal corresponded to longer word-reading time, and this effect was stronger when surprisal values were estimated by the neural network. In addition, there was an early, positive effect of surprisal on pupil size, from about 250 ms before word fixation until 100 ms after fixation. This early effect, which was only significant for the network-based surprisal estimates, is suggestive of a preparation-based account of surprisal.

- by Stefan Frank
- •
- Eye tracking, Connectionist Modeling, Reading, Pupillometry

Neurodevelopmental spectrum disorders like autism (ASD) are diagnosed, on average, beyond age 4 y, after multiple critical periods of brain development close and behavioral intervention becomes less effective. This raises the urgent need for quantitative, noninvasive, and translational biomarkers for their early detection and tracking. We found that both idiopathic (BTBR) and genetic (CDKL5- and MeCP2-deficient) mouse models of ASD display an early, impaired cholinergic neuromodulation as reflected in altered spontaneous pupil fluctuations. Abnormalities were already present before the onset of symptoms and were rescued by the selective expression of MeCP2 in cholinergic circuits. Hence, we trained a neural network (ConvNetACh) to recognize, with 97% accuracy, patterns of these arousal fluctuations in mice with enhanced cholinergic sensitivity (LYNX1-deficient). ConvNetACh then successfully detected impairments in all ASD mouse models tested except in MeCP2-rescued mice. By retraini...

- by Ryan T Miller
- •
- Second Language Acquisition, Eye tracking, Pupillometry, Input Enhancement

Background: Despite the multisensory nature of perception, previous research on emotions has been focused on unimodal emotional cues with visual stimuli. To the best of our knowledge, there is no evidence on the extent to which incongruent emotional cues from visual and auditory sensory channels affect pupil size. Aims: To investigate the effects of audiovisual emotional information perception on the physiological and affective response, but also to determine the impact of mismatched cues in emotional perception on these physiological indexes. Method: Pupil size, electrodermal activity and affective subjective responses were recorded while 30 participants were exposed to visual and auditory stimuli with varied emotional content in three different experimental conditions: pictures and sounds presented alone (unimodal), emotionally matched audio-visual stimuli (bimodal congruent) and emotionally mismatched audio-visual stimuli (bimodal incongruent). Results: The data revealed no effect of emotional incongruence on physiological and affective responses. On the other hand, pupil size covaried with skin conductance response (SCR), but the subjective experience was partially dissociated from autonomic responses. Conclusion: Emotional stimuli are able to trigger physiological responses regardless of valence, sensory modality or level of emotional congruence.

- by Pedro J Rosa
- •
- Emotion, Eye tracking, Pupillometry, Electrodermal Activity

During recognition memory tests participants" pupils dilate more when they view old items compared to novel items. We sought to replicate this "pupil old/new effect" and to determine its relationship to participants" responses. We compared changes in pupil size during recognition when participants were given standard recognition memory instructions, instructions to feign amnesia and instructions to report all items as new. Participants" pupils dilated more to old items compared to new items under all three instruction conditions. This finding suggests that the increase in pupil size that occurs when participants encounter previously studied items is not under conscious control. Given that pupil size can be reliably and simply measured, the pupil old/new effect may have potential in clinical settings as a means for determining whether patients are feigning memory loss.

- by Becky Heaver
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- Psychology, Cognitive Science, Eye tracking, Deception / Lying (Deception Lying)

Dynamic changes of pupil dilation represent an established indicator of cognitive load in cognitive sciences Exploitation of these insights regarding pupil dilation as an indicator of cog-nitive load for attention-aware Information and Communication (ICT) systems has been impeded due to restrictions of pupil analysis to a posteriori processing and exclusion of disturbing environmental factors. To overcome these issues, this paper proposes an algorithm based on Hoeks's pupil response model, enabling online analysis of pupil dilation for the dynamic interpretation of cognitive load as an input for interactive, attention-aware systems, which outperforms state-of-the-art approaches regarding complexity, accuracy, flexibility and computation time. Beyond mathematical pupil modeling, this paper identifies Environment Illumination compensation (IC), Blink Compensation (BC), Reference Baseline computation (RB) and Onset/Offset detection (OO) as crucial fields of research for the transfe...

- by Benedikt Gollan
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- Computer Science, Visual attention, Attention, Pupillometry

- by Jane Opie
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- Eye tracking, Speech perception, Pupillometry, Individual Differences

Cognitive science has established widely used and validated procedures for evaluating working memory in numerous applied domains, but surprisingly few studies have employed these methodologies to assess claims about the impacts of visualizations on working memory. The lack of information visualization research that uses validated procedures for measuring working memory may be due, in part, to the absence of cross-domain methodological guidance tailored explicitly to the unique needs of visualization research. This paper presents a set of clear, practical, and empirically validated methods for evaluating working memory during visualization tasks and provides readers with guidance in selecting an appropriate working memory evaluation paradigm. As a case study, we illustrate multiple methods for evaluating working memory in a visual-spatial aggregation task with geospatial data. The results show that the use of dual-task experimental designs (simultaneous performance of several tasks compared to single-task performance) and pupil dilation can reveal working memory demands associated with task difficulty and dual-tasking. In a dual-task experimental design, measures of task completion times and pupillometry revealed the working memory demands associated with both task difficulty and dual-tasking. Pupillometry demonstrated that participants' pupils were significantly larger when they were completing a more difficult task and when multitasking. We propose that researchers interested in the relative differences in working memory between visualizations should consider a converging methods approach, where physiological measures and behavioral measures of working memory are employed to generate a rich evaluation of visualization effort.

- by Spencer C . Castro
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- Visualization, Working Memory, Pupillometry, Dual Task

Few studies have used matched affective paradigms to compare humans and non-human primates. In monkeys with amygdala lesions and youth with anxiety disorders, we examined cross-species pupillary responses during a saccade-based, affective attentional capture task. Given evidence of enhanced amygdala function in anxiety, we hypothesized that opposite patterns would emerge in lesioned monkeys and anxious participants. A total of 53 unmedicated youths (27 anxious, 26 healthy) and 8 adult male rhesus monkeys (Macaca mulatta) completed matched behavioral paradigms. Four monkeys received bilateral excitotoxic amygdala lesions and four served as unoperated controls. Compared to healthy youth, anxious youth exhibited increased pupillary constriction in response to emotional and non-emotional distractors (F(1,48) = 6.28, P = 0.02, η 2 p = 0.12). Pupillary response was associated significantly with anxiety symptoms severity (F(1,48) = 5.59, P = 0.02, η 2 p = 0.10). As hypothesized, lesioned monkeys exhibited the opposite pattern i.e. decreased pupillary constriction in response to distractors, compared to unoperated control monkeys (F(1,32) = 24.22, P < 0.001, η 2 = 0.33). Amygdala lesioned monkeys and youth with anxiety disorders show opposite patterns of pupil constriction in the context of an affective distractor task. Such findings suggest the presence of altered amygdala circuitry functioning in anxiety. Future lesion and human neuroimaging work might examine the way in which specific amygdala sub-nuclei and downstream circuits mediate these effects.

- by Vincent D . Costa
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- Cognitive Psychology, Emotion, Eye tracking, Affective Neuroscience

Rij, J. van., P. Hendriks, H. van Rijn, R. H. Baayen., and S. N. Wood
This article provides a tutorial for analyzing pupillometric data. Pupil dilation has become increasingly popular in psychological and psycholinguistic research as a measure to trace language processing. However, there is no general consensus about procedures to analyze the data, with most studies analyzing extracted features from the pupil dilation data instead of analyzing the pupil dilation trajectories directly. Recent studies have started to apply nonlinear regression and other methods to analyze the pupil dilation trajectories directly, utilizing all available information in the continuously measured signal. This article applies a nonlinear regression analysis, generalized additive mixed modeling, and illustrates how to analyze the full-time course of the pupil dilation signal. The regression analysis is particularly suited for analyzing pupil dilation in the fields of psychological and psycholinguistic research because generalized additive mixed models can include complex nonlinear interactions for investigating the effects of properties of stimuli (e.g., formant frequency) or participants (e.g., working memory score) on the pupil dilation signal. To account for the variation due to participants and items, nonlinear random effects can be included. However, one of the challenges for analyzing time series data is dealing with the autocorrelation in the residuals, which is rather extreme for the pupillary signal. On the basis of simulations, we explain potential causes of this extreme autocorrelation, and on the basis of the experimental data, we show how to reduce their adverse effects, allowing a much more coherent interpretation of pupillary data than possible with feature-based techniques.

- by Harald Baayen
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- Statistical Analysis, Pupillometry, Autocorrelation, Preprocessing

Pupil size differs significantly during mind wandering periods compared to periods of focusing on breath. Pupil size appears to be a promising biophysical marker to monitor mind wandering episodes. A clear departure in term of pupil size can be seen between the focusing period and the mind wandering period. From-20 to-10 seconds before the button press signaling a mind wandering episode, the pupil size is smaller than the pupil size during the start of the shown focus period. After-10 seconds, pupil size increases and largely exceeds the pupil size observed during the focus period. Our interpretation is that pupil size reflect alertness. This is supported by a previous study showing that during the mind wandering episode alertness is lower than during breath focus periods (Braboszcz & Delorme).

- by Romain Grandchamp
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- Phenomenology, Pupillometry, Cognitive Neuroscience, Mind Wandering

It has long been established that the pupil diameter increases during mental activities in proportion to the difficulty of the task at hand. However, it is still unclear whether this relationship between the pupil size and effort applies also to physical effort. In order to address this issue, we asked healthy volunteers to perform a power grip task, at varied intensity, while evaluating their effort both implicitly and explicitly, and while concurrently monitoring their pupil size. Each trial started with a contraction of imposed intensity, under the control of a continuous visual feedback. Upon completion of the contraction, participants had to choose whether to replicate, without feedback, the first contraction for a variable monetary reward, or whether to skip this step and go directly to the next trial. The rate of acceptance of effort replication and the amount of force exerted during the replication were used as implicit measures of the perception of the effort exerted during the first contraction. In addition, the participants were asked to rate on an analog scale, their explicit perception of the effort for each intensity condition. We found that pupil diameter increased during physical effort and that the magnitude of this response reflected not only the actual intensity of the contraction but also the subjects’ perception of the effort. This finding indicates that the pupil size signals the level of effort invested in a task, irrespective of whether it is physical or mental. It also helps refining the potential brain circuits involved since the results of the current study imply a convergence of mental and physical effort information at some level along this pathway.

- by Alexandre Zénon and +1
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- Pupillometry, Effort
- by Sumeyya Atmaca
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- Eye tracking, Pupillometry, Flash Photography