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Sample records for human gaze direction

  1. Goats display audience-dependent human-directed gazing behaviour in a problem-solving task.

    Science.gov (United States)

    Nawroth, Christian; Brett, Jemma M; McElligott, Alan G

    2016-07-01

    Domestication is an important factor driving changes in animal cognition and behaviour. In particular, the capacity of dogs to communicate in a referential and intentional way with humans is considered a key outcome of how domestication as a companion animal shaped the canid brain. However, the lack of comparison with other domestic animals makes general conclusions about how domestication has affected these important cognitive features difficult. We investigated human-directed behaviour in an 'unsolvable problem' task in a domestic, but non-companion species: goats. During the test, goats experienced a forward-facing or an away-facing person. They gazed towards the forward-facing person earlier and for longer and showed more gaze alternations and a lower latency until the first gaze alternation when the person was forward-facing. Our results provide strong evidence for audience-dependent human-directed visual orienting behaviour in a species that was domesticated primarily for production, and show similarities with the referential and intentional communicative behaviour exhibited by domestic companion animals such as dogs and horses. This indicates that domestication has a much broader impact on heterospecific communication than previously believed. © 2016 The Author(s).

  2. Owners' direct gazes increase dogs' attention-getting behaviors.

    Science.gov (United States)

    Ohkita, Midori; Nagasawa, Miho; Kazutaka, Mogi; Kikusui, Takefumi

    2016-04-01

    This study examined whether dogs gain information about human's attention via their gazes and whether they change their attention-getting behaviors (i.e., whining and whimpering, looking at their owners' faces, pawing, and approaching their owners) in response to their owners' direct gazes. The results showed that when the owners gazed at their dogs, the durations of whining and whimpering and looking at the owners' faces were longer than when the owners averted their gazes. In contrast, there were no differences in duration of pawing and likelihood of approaching the owners between the direct and averted gaze conditions. Therefore, owners' direct gazes increased the behaviors that acted as distant signals and did not necessarily involve touching the owners. We suggest that dogs are sensitive to human gazes, and this sensitivity may act as attachment signals to humans, and may contribute to close relationships between humans and dogs. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Predicting gaze direction from head pose yaw and pitch

    NARCIS (Netherlands)

    Johnson, D.O.; Cuijpers, R.H.; Arabnia, H.R.; Deligiannidis, L.; Lu, J.; Tinetti, F.G.; You, J.

    2013-01-01

    Abstract - Socially assistive robots (SARs) must be able to interpret non-verbal communication from a human. A person’s gaze direction informs the observer where the visual attention is directed to. Therefore it is useful if a robot can interpret the gaze direction, so that it can assess whether a

  4. AmbiGaze : direct control of ambient devices by gaze

    OpenAIRE

    Velloso, Eduardo; Wirth, Markus; Weichel, Christian; Abreu Esteves, Augusto Emanuel; Gellersen, Hans-Werner Georg

    2016-01-01

    Eye tracking offers many opportunities for direct device control in smart environments, but issues such as the need for calibration and the Midas touch problem make it impractical. In this paper, we propose AmbiGaze, a smart environment that employs the animation of targets to provide users with direct control of devices by gaze only through smooth pursuit tracking. We propose a design space of means of exposing functionality through movement and illustrate the concept through four prototypes...

  5. Social communication with virtual agents: The effects of body and gaze direction on attention and emotional responding in human observers.

    Science.gov (United States)

    Marschner, Linda; Pannasch, Sebastian; Schulz, Johannes; Graupner, Sven-Thomas

    2015-08-01

    In social communication, the gaze direction of other persons provides important information to perceive and interpret their emotional response. Previous research investigated the influence of gaze by manipulating mutual eye contact. Therefore, gaze and body direction have been changed as a whole, resulting in only congruent gaze and body directions (averted or directed) of another person. Here, we aimed to disentangle these effects by using short animated sequences of virtual agents posing with either direct or averted body or gaze. Attention allocation by means of eye movements, facial muscle response, and emotional experience to agents of different gender and facial expressions were investigated. Eye movement data revealed longer fixation durations, i.e., a stronger allocation of attention, when gaze and body direction were not congruent with each other or when both were directed towards the observer. This suggests that direct interaction as well as incongruous signals increase the demands of attentional resources in the observer. For the facial muscle response, only the reaction of muscle zygomaticus major revealed an effect of body direction, expressed by stronger activity in response to happy expressions for direct compared to averted gaze when the virtual character's body was directed towards the observer. Finally, body direction also influenced the emotional experience ratings towards happy expressions. While earlier findings suggested that mutual eye contact is the main source for increased emotional responding and attentional allocation, the present results indicate that direction of the virtual agent's body and head also plays a minor but significant role. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Eye gazing direction inspection based on image processing technique

    Science.gov (United States)

    Hao, Qun; Song, Yong

    2005-02-01

    According to the research result in neural biology, human eyes can obtain high resolution only at the center of view of field. In the research of Virtual Reality helmet, we design to detect the gazing direction of human eyes in real time and feed it back to the control system to improve the resolution of the graph at the center of field of view. In the case of current display instruments, this method can both give attention to the view field of virtual scene and resolution, and improve the immersion of virtual system greatly. Therefore, detecting the gazing direction of human eyes rapidly and exactly is the basis of realizing the design scheme of this novel VR helmet. In this paper, the conventional method of gazing direction detection that based on Purklinje spot is introduced firstly. In order to overcome the disadvantage of the method based on Purklinje spot, this paper proposed a method based on image processing to realize the detection and determination of the gazing direction. The locations of pupils and shapes of eye sockets change with the gazing directions. With the aid of these changes, analyzing the images of eyes captured by the cameras, gazing direction of human eyes can be determined finally. In this paper, experiments have been done to validate the efficiency of this method by analyzing the images. The algorithm can carry out the detection of gazing direction base on normal eye image directly, and it eliminates the need of special hardware. Experiment results show that the method is easy to implement and have high precision.

  7. Early Left Parietal Activity Elicited by Direct Gaze: A High-Density EEG Study

    Science.gov (United States)

    Burra, Nicolas; Kerzel, Dirk; George, Nathalie

    2016-01-01

    Gaze is one of the most important cues for human communication and social interaction. In particular, gaze contact is the most primary form of social contact and it is thought to capture attention. A very early-differentiated brain response to direct versus averted gaze has been hypothesized. Here, we used high-density electroencephalography to test this hypothesis. Topographical analysis allowed us to uncover a very early topographic modulation (40–80 ms) of event-related responses to faces with direct as compared to averted gaze. This modulation was obtained only in the condition where intact broadband faces–as opposed to high-pass or low-pas filtered faces–were presented. Source estimation indicated that this early modulation involved the posterior parietal region, encompassing the left precuneus and inferior parietal lobule. This supports the idea that it reflected an early orienting response to direct versus averted gaze. Accordingly, in a follow-up behavioural experiment, we found faster response times to the direct gaze than to the averted gaze broadband faces. In addition, classical evoked potential analysis showed that the N170 peak amplitude was larger for averted gaze than for direct gaze. Taken together, these results suggest that direct gaze may be detected at a very early processing stage, involving a parallel route to the ventral occipito-temporal route of face perceptual analysis. PMID:27880776

  8. Is gaze following purely reflexive or goal-directed instead? Revisiting the automaticity of orienting attention by gaze cues.

    Science.gov (United States)

    Ricciardelli, Paola; Carcagno, Samuele; Vallar, Giuseppe; Bricolo, Emanuela

    2013-01-01

    Distracting gaze has been shown to elicit automatic gaze following. However, it is still debated whether the effects of perceived gaze are a simple automatic spatial orienting response or are instead sensitive to the context (i.e. goals and task demands). In three experiments, we investigated the conditions under which gaze following occurs. Participants were instructed to saccade towards one of two lateral targets. A face distracter, always present in the background, could gaze towards: (a) a task-relevant target--("matching" goal-directed gaze shift)--congruent or incongruent with the instructed direction, (b) a task-irrelevant target, orthogonal to the one instructed ("non-matching" goal-directed gaze shift), or (c) an empty spatial location (no-goal-directed gaze shift). Eye movement recordings showed faster saccadic latencies in correct trials in congruent conditions especially when the distracting gaze shift occurred before the instruction to make a saccade. Interestingly, while participants made a higher proportion of gaze-following errors (i.e. errors in the direction of the distracting gaze) in the incongruent conditions when the distracter's gaze shift preceded the instruction onset indicating an automatic gaze following, they never followed the distracting gaze when it was directed towards an empty location or a stimulus that was never the target. Taken together, these findings suggest that gaze following is likely to be a product of both automatic and goal-driven orienting mechanisms.

  9. Estimating the gaze of a virtuality human.

    Science.gov (United States)

    Roberts, David J; Rae, John; Duckworth, Tobias W; Moore, Carl M; Aspin, Rob

    2013-04-01

    The aim of our experiment is to determine if eye-gaze can be estimated from a virtuality human: to within the accuracies that underpin social interaction; and reliably across gaze poses and camera arrangements likely in every day settings. The scene is set by explaining why Immersive Virtuality Telepresence has the potential to meet the grand challenge of faithfully communicating both the appearance and the focus of attention of a remote human participant within a shared 3D computer-supported context. Within the experiment n=22 participants rotated static 3D virtuality humans, reconstructed from surround images, until they felt most looked at. The dependent variable was absolute angular error, which was compared to that underpinning social gaze behaviour in the natural world. Independent variables were 1) relative orientations of eye, head and body of captured subject; and 2) subset of cameras used to texture the form. Analysis looked for statistical and practical significance and qualitative corroborating evidence. The analysed results tell us much about the importance and detail of the relationship between gaze pose, method of video based reconstruction, and camera arrangement. They tell us that virtuality can reproduce gaze to an accuracy useful in social interaction, but with the adopted method of Video Based Reconstruction, this is highly dependent on combination of gaze pose and camera arrangement. This suggests changes in the VBR approach in order to allow more flexible camera arrangements. The work is of interest to those wanting to support expressive meetings that are both socially and spatially situated, and particular those using or building Immersive Virtuality Telepresence to accomplish this. It is also of relevance to the use of virtuality humans in applications ranging from the study of human interactions to gaming and the crossing of the stage line in films and TV.

  10. The impact of visual gaze direction on auditory object tracking

    OpenAIRE

    Pomper, U.; Chait, M.

    2017-01-01

    Subjective experience suggests that we are able to direct our auditory attention independent of our visual gaze, e.g when shadowing a nearby conversation at a cocktail party. But what are the consequences at the behavioural and neural level? While numerous studies have investigated both auditory attention and visual gaze independently, little is known about their interaction during selective listening. In the present EEG study, we manipulated visual gaze independently of auditory attention wh...

  11. Just one look: Direct gaze briefly disrupts visual working memory.

    Science.gov (United States)

    Wang, J Jessica; Apperly, Ian A

    2017-04-01

    Direct gaze is a salient social cue that affords rapid detection. A body of research suggests that direct gaze enhances performance on memory tasks (e.g., Hood, Macrae, Cole-Davies, & Dias, Developmental Science, 1, 67-71, 2003). Nonetheless, other studies highlight the disruptive effect direct gaze has on concurrent cognitive processes (e.g., Conty, Gimmig, Belletier, George, & Huguet, Cognition, 115(1), 133-139, 2010). This discrepancy raises questions about the effects direct gaze may have on concurrent memory tasks. We addressed this topic by employing a change detection paradigm, where participants retained information about the color of small sets of agents. Experiment 1 revealed that, despite the irrelevance of the agents' eye gaze to the memory task at hand, participants were worse at detecting changes when the agents looked directly at them compared to when the agents looked away. Experiment 2 showed that the disruptive effect was relatively short-lived. Prolonged presentation of direct gaze led to recovery from the initial disruption, rather than a sustained disruption on change detection performance. The present study provides the first evidence that direct gaze impairs visual working memory with a rapidly-developing yet short-lived effect even when there is no need to attend to agents' gaze.

  12. Fearful gaze cueing: gaze direction and facial expression independently influence overt orienting responses in 12-month-olds.

    Directory of Open Access Journals (Sweden)

    Reiko Matsunaka

    Full Text Available Gaze direction cues and facial expressions have been shown to influence object processing in infants. For example, infants around 12 months of age utilize others' gaze directions and facial expressions to regulate their own behaviour toward an ambiguous target (i.e., social referencing. However, the mechanism by which social signals influence overt orienting in infants is unclear. The present study examined the effects of static gaze direction cues and facial expressions (neutral vs. fearful on overt orienting using a gaze-cueing paradigm in 6- and 12-month-old infants. Two experiments were conducted: in Experiment 1, a face with a leftward or rightward gaze direction was used as a cue, and a face with a forward gaze direction was added in Experiment 2. In both experiments, an effect of facial expression was found in 12-month-olds; no effect was found in 6-month-olds. Twelve-month-old infants exhibited more rapid overt orienting in response to fearful expressions than neutral expressions, irrespective of gaze direction. These findings suggest that gaze direction information and facial expressions independently influence overt orienting in infants, and the effect of facial expression emerges earlier than that of static gaze direction. Implications for the development of gaze direction and facial expression processing systems are discussed.

  13. Direct Speaker Gaze Promotes Trust in Truth-Ambiguous Statements.

    Science.gov (United States)

    Kreysa, Helene; Kessler, Luise; Schweinberger, Stefan R

    2016-01-01

    A speaker's gaze behaviour can provide perceivers with a multitude of cues which are relevant for communication, thus constituting an important non-verbal interaction channel. The present study investigated whether direct eye gaze of a speaker affects the likelihood of listeners believing truth-ambiguous statements. Participants were presented with videos in which a speaker produced such statements with either direct or averted gaze. The statements were selected through a rating study to ensure that participants were unlikely to know a-priori whether they were true or not (e.g., "sniffer dogs cannot smell the difference between identical twins"). Participants indicated in a forced-choice task whether or not they believed each statement. We found that participants were more likely to believe statements by a speaker looking at them directly, compared to a speaker with averted gaze. Moreover, when participants disagreed with a statement, they were slower to do so when the statement was uttered with direct (compared to averted) gaze, suggesting that the process of rejecting a statement as untrue may be inhibited when that statement is accompanied by direct gaze.

  14. Direct Speaker Gaze Promotes Trust in Truth-Ambiguous Statements.

    Directory of Open Access Journals (Sweden)

    Helene Kreysa

    Full Text Available A speaker's gaze behaviour can provide perceivers with a multitude of cues which are relevant for communication, thus constituting an important non-verbal interaction channel. The present study investigated whether direct eye gaze of a speaker affects the likelihood of listeners believing truth-ambiguous statements. Participants were presented with videos in which a speaker produced such statements with either direct or averted gaze. The statements were selected through a rating study to ensure that participants were unlikely to know a-priori whether they were true or not (e.g., "sniffer dogs cannot smell the difference between identical twins". Participants indicated in a forced-choice task whether or not they believed each statement. We found that participants were more likely to believe statements by a speaker looking at them directly, compared to a speaker with averted gaze. Moreover, when participants disagreed with a statement, they were slower to do so when the statement was uttered with direct (compared to averted gaze, suggesting that the process of rejecting a statement as untrue may be inhibited when that statement is accompanied by direct gaze.

  15. The impact of visual gaze direction on auditory object tracking.

    Science.gov (United States)

    Pomper, Ulrich; Chait, Maria

    2017-07-05

    Subjective experience suggests that we are able to direct our auditory attention independent of our visual gaze, e.g when shadowing a nearby conversation at a cocktail party. But what are the consequences at the behavioural and neural level? While numerous studies have investigated both auditory attention and visual gaze independently, little is known about their interaction during selective listening. In the present EEG study, we manipulated visual gaze independently of auditory attention while participants detected targets presented from one of three loudspeakers. We observed increased response times when gaze was directed away from the locus of auditory attention. Further, we found an increase in occipital alpha-band power contralateral to the direction of gaze, indicative of a suppression of distracting input. Finally, this condition also led to stronger central theta-band power, which correlated with the observed effect in response times, indicative of differences in top-down processing. Our data suggest that a misalignment between gaze and auditory attention both reduce behavioural performance and modulate underlying neural processes. The involvement of central theta-band and occipital alpha-band effects are in line with compensatory neural mechanisms such as increased cognitive control and the suppression of task irrelevant inputs.

  16. Race perception and gaze direction differently impair visual working memory for faces: An event-related potential study.

    Science.gov (United States)

    Sessa, Paola; Dalmaso, Mario

    2016-01-01

    Humans are amazingly experts at processing and recognizing faces, however there are moderating factors of this ability. In the present study, we used the event-related potential technique to investigate the influence of both race and gaze direction on visual working memory (i.e., VWM) face representations. In a change detection task, we orthogonally manipulated race (own-race vs. other-race faces) and eye-gaze direction (direct gaze vs. averted gaze). Participants were required to encode identities of these faces. We quantified the amount of information encoded in VWM by monitoring the amplitude of the sustained posterior contralateral negativity (SPCN) time-locked to the faces. Notably, race and eye-gaze direction differently modulated SPCN amplitude such that other-race faces elicited reduced SPCN amplitudes compared with own-race faces only when displaying a direct gaze. On the other hand, faces displaying averted gaze, independently of their race, elicited increased SPCN amplitudes compared with faces displaying direct gaze. We interpret these findings as denoting that race and eye-gaze direction affect different face processing stages.

  17. Wolves (Canis lupus) and Dogs (Canis familiaris) Differ in Following Human Gaze Into Distant Space But Respond Similar to Their Packmates’ Gaze

    Science.gov (United States)

    Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

    2017-01-01

    Gaze following into distant space is defined as visual co-orientation with another individual’s head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. PMID:27244538

  18. Wolves (Canis lupus) and dogs (Canis familiaris) differ in following human gaze into distant space but respond similar to their packmates' gaze.

    Science.gov (United States)

    Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

    2016-08-01

    Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. Gazes

    DEFF Research Database (Denmark)

    Khawaja, Iram

    , and the different strategies of positioning they utilize are studied and identified. The first strategy is to confront stereotyping prejudices and gazes, thereby attempting to position oneself in a counteracting way. The second is to transform and try to normalise external characteristics, such as clothing...... and other symbols that indicate Muslimness. A third strategy is to play along and allow the prejudice in question to remain unchallenged. A fourth is to join and participate in religious communities and develop an alternate sense of belonging to a wider community of Muslims. The concept of panoptical gazes...

  20. "Wolves (Canis lupus) and dogs (Canis familiaris) differ in following human gaze into distant space but respond similar to their packmates' gaze": Correction to Werhahn et al. (2016).

    Science.gov (United States)

    2017-02-01

    Reports an error in "Wolves ( Canis lupus ) and dogs ( Canis familiaris ) differ in following human gaze into distant space but respond similar to their packmates' gaze" by Geraldine Werhahn, Zsófia Virányi, Gabriela Barrera, Andrea Sommese and Friederike Range ( Journal of Comparative Psychology , 2016[Aug], Vol 130[3], 288-298). In the article, the affiliations for the second and fifth authors should be Wolf Science Center, Ernstbrunn, Austria, and Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna/ Medical University of Vienna/University of Vienna. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2016-26311-001.) Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills

  1. Influence of Gaze Direction on Face Recognition: A Sensitive Effect

    Directory of Open Access Journals (Sweden)

    Noémy Daury

    2011-08-01

    Full Text Available This study was aimed at determining the conditions in which eye-contact may improve recognition memory for faces. Different stimuli and procedures were tested in four experiments. The effect of gaze direction on memory was found when a simple “yes-no” recognition task was used but not when the recognition task was more complex (e.g., including “Remember-Know” judgements, cf. Experiment 2, or confidence ratings, cf. Experiment 4. Moreover, even when a “yes-no” recognition paradigm was used, the effect occurred with one series of stimuli (cf. Experiment 1 but not with another one (cf. Experiment 3. The difficulty to produce the positive effect of gaze direction on memory is discussed.

  2. Revisiting the Relationship between the Processing of Gaze Direction and the Processing of Facial Expression

    Science.gov (United States)

    Ganel, Tzvi

    2011-01-01

    There is mixed evidence on the nature of the relationship between the perception of gaze direction and the perception of facial expressions. Major support for shared processing of gaze and expression comes from behavioral studies that showed that observers cannot process expression or gaze and ignore irrelevant variations in the other dimension.…

  3. Spatial updating depends on gaze direction even after loss of vision.

    Science.gov (United States)

    Reuschel, Johanna; Rösler, Frank; Henriques, Denise Y P; Fiehler, Katja

    2012-02-15

    Direction of gaze (eye angle + head angle) has been shown to be important for representing space for action, implying a crucial role of vision for spatial updating. However, blind people have no access to vision yet are able to perform goal-directed actions successfully. Here, we investigated the role of visual experience for localizing and updating targets as a function of intervening gaze shifts in humans. People who differed in visual experience (late blind, congenitally blind, or sighted) were briefly presented with a proprioceptive reach target while facing it. Before they reached to the target's remembered location, they turned their head toward an eccentric direction that also induced corresponding eye movements in sighted and late blind individuals. We found that reaching errors varied systematically as a function of shift in gaze direction only in participants with early visual experience (sighted and late blind). In the late blind, this effect was solely present in people with moveable eyes but not in people with at least one glass eye. Our results suggest that the effect of gaze shifts on spatial updating develops on the basis of visual experience early in life and remains even after loss of vision as long as feedback from the eyes and head is available.

  4. Gazing toward humans: a study on water rescue dogs using the impossible task paradigm.

    Science.gov (United States)

    D'Aniello, Biagio; Scandurra, Anna; Prato-Previde, Emanuela; Valsecchi, Paola

    2015-01-01

    Various studies have assessed the role of life experiences, including learning opportunities, living conditions and the quality of dog-human relationships, in the use of human cues and problem-solving ability. The current study investigates how and to what extent training affects the behaviour of dogs and the communication of dogs with humans by comparing dogs trained for a water rescue service and untrained pet dogs in the impossible task paradigm. Twenty-three certified water rescue dogs (the water rescue group) and 17 dogs with no training experience (the untrained group) were tested using a modified version of the impossible task described by Marshall-Pescini et al. in 2009. The results demonstrated that the water rescue dogs directed their first gaze significantly more often towards the owner and spent more time gazing toward two people compared to the untrained pet dogs. There was no difference between the dogs of the two groups as far as in the amount of time spent gazing at the owner or the stranger; neither in the interaction with the apparatus attempting to obtain food. The specific training regime, aimed at promoting cooperation during the performance of water rescue, could account for the longer gazing behaviour shown toward people by the water rescue dogs and the priority of gazing toward the owner. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. How Do We Update Faces? Effects of Gaze Direction and Facial Expressions on Working Memory Updating

    OpenAIRE

    Artuso, Caterina; Palladino, Paola; Ricciardelli, Paola

    2012-01-01

    The aim of the study was to investigate how the biological binding between different facial dimensions, and their social and communicative relevance, may impact updating processes in working memory (WM). We focused on WM updating because it plays a key role in ongoing processing. Gaze direction and facial expression are crucial and changeable components of face processing. Direct gaze enhances the processing of approach-oriented facial emotional expressions (e.g., joy), while averted gaze enh...

  6. Direct gaze elicits atypical activation of the theory-of-mind network in autism spectrum conditions.

    Science.gov (United States)

    von dem Hagen, Elisabeth A H; Stoyanova, Raliza S; Rowe, James B; Baron-Cohen, Simon; Calder, Andrew J

    2014-06-01

    Eye contact plays a key role in social interaction and is frequently reported to be atypical in individuals with autism spectrum conditions (ASCs). Despite the importance of direct gaze, previous functional magnetic resonance imaging in ASC has generally focused on paradigms using averted gaze. The current study sought to determine the neural processing of faces displaying direct and averted gaze in 18 males with ASC and 23 matched controls. Controls showed an increased response to direct gaze in brain areas implicated in theory-of-mind and gaze perception, including medial prefrontal cortex, temporoparietal junction, posterior superior temporal sulcus region, and amygdala. In contrast, the same regions showed an increased response to averted gaze in individuals with an ASC. This difference was confirmed by a significant gaze direction × group interaction. Relative to controls, participants with ASC also showed reduced functional connectivity between these regions. We suggest that, in the typical brain, perceiving another person gazing directly at you triggers spontaneous attributions of mental states (e.g. he is "interested" in me), and that such mental state attributions to direct gaze may be reduced or absent in the autistic brain.

  7. Effects of Facial Symmetry and Gaze Direction on Perception of Social Attributes: A Study in Experimental Art History

    Directory of Open Access Journals (Sweden)

    Per Olav Folgerø

    2016-09-01

    Full Text Available This article explores the possibility of testing hypotheses about art production in the past by collecting data in the present. We call this enterprise experimental art history. Why did medieval artists prefer to paint Christ with his face directed towards the beholder, while profane faces were noticeably more often painted in different degrees of profile? Is a preference for frontal faces motivated by deeper evolutionary and biological considerations? Head and gaze direction is a significant factor for detecting the intentions of others, and accurate detection of gaze direction depends on strong contrast between a dark iris and a bright sclera, a combination that is only found in humans among the primates. One uniquely human capacity is language acquisition, where the detection of shared or joint attention, for example through detection of gaze direction, contributes significantly to the ease of acquisition. The perceived face and gaze direction is also related to fundamental emotional reactions such as fear, aggression, empathy and sympathy. The fast-track modulator model presents a related fast and unconscious subcortical route that involves many central brain areas. Activity in this pathway mediates the affective valence of the stimulus. In particular different sub-regions of the amygdala show specific activation as response to gaze direction, head orientation, and the valence of facial expression.We present three experiments on the effects of face orientation and gaze direction on the judgments of social attributes. We observed that frontal faces with direct gaze were more highly associated with positive adjectives. Does this help to associate positive values to the Holy Face in a Western context? The formal result indicates that the Holy Face is perceived more positively than profiles with both direct and averted gaze. Two control studies, using a Brazilian and a Dutch database of photographs, showed a similar but weaker effect with a

  8. Does Gaze Direction Modulate Facial Expression Processing in Children with Autism Spectrum Disorder?

    Science.gov (United States)

    Akechi, Hironori; Senju, Atsushi; Kikuchi, Yukiko; Tojo, Yoshikuni; Osanai, Hiroo; Hasegawa, Toshikazu

    2009-01-01

    Two experiments investigated whether children with autism spectrum disorder (ASD) integrate relevant communicative signals, such as gaze direction, when decoding a facial expression. In Experiment 1, typically developing children (9-14 years old; n = 14) were faster at detecting a facial expression accompanying a gaze direction with a congruent…

  9. The Eyes Are the Windows to the Mind: Direct Eye Gaze Triggers the Ascription of Others' Minds.

    Science.gov (United States)

    Khalid, Saara; Deska, Jason C; Hugenberg, Kurt

    2016-12-01

    Eye gaze is a potent source of social information with direct eye gaze signaling the desire to approach and averted eye gaze signaling avoidance. In the current work, we proposed that eye gaze signals whether or not to impute minds into others. Across four studies, we manipulated targets' eye gaze (i.e., direct vs. averted eye gaze) and measured explicit mind ascriptions (Study 1a, Study 1b, and Study 2) and beliefs about the likelihood of targets having mind (Study 3). In all four studies, we find novel evidence that the ascription of sophisticated humanlike minds to others is signaled by the display of direct eye gaze relative to averted eye gaze. Moreover, we provide evidence suggesting that this differential mentalization is due, at least in part, to beliefs that direct gaze targets are more likely to instigate social interaction. In short, eye contact triggers mind perception. © 2016 by the Society for Personality and Social Psychology, Inc.

  10. Trait Anxiety Impacts the Perceived Gaze Direction of Fearful But Not Angry Faces

    Directory of Open Access Journals (Sweden)

    Zhonghua Hu

    2017-07-01

    Full Text Available Facial expression and gaze direction play an important role in social communication. Previous research has demonstrated the perception of anger is enhanced by direct gaze, whereas, it is unclear whether perception of fear is enhanced by averted gaze. In addition, previous research has shown the anxiety affects the processing of facial expression and gaze direction, but hasn’t measured or controlled for depression. As a result, firm conclusions cannot be made regarding the impact of individual differences in anxiety and depression on perceptions of face expressions and gaze direction. The current study attempted to reexamine the effect of the anxiety level on the processing of facial expressions and gaze direction by matching participants on depression scores. A reliable psychophysical index of the range of eye gaze angles judged as being directed at oneself [the cone of direct gaze (CoDG] was used as the dependent variable in this study. Participants were stratified into high/low trait anxiety groups and asked to judge the gaze of angry, fearful, and neutral faces across a range of gaze directions. The result showed: (1 the perception of gaze direction was influenced by facial expression and this was modulated by trait anxiety. For the high trait anxiety group, the CoDG for angry expressions was wider than for fearful and neutral expressions, and no significant difference emerged between fearful and neutral expressions; For the low trait anxiety group, the CoDG for both angry and fearful expressions was wider than for neutral, and no significant difference emerged between angry and fearful expressions. (2 Trait anxiety modulated the perception of gaze direction only in the fearful condition, such that the fearful CoDG for the high trait anxiety group was narrower than the low trait anxiety group. This demonstrated that anxiety distinctly affected gaze perception in expressions that convey threat (angry, fearful, such that a high trait anxiety

  11. Photographic but not line-drawn faces show early perceptual neural sensitivity to eye gaze direction

    Directory of Open Access Journals (Sweden)

    Alejandra eRossi

    2015-04-01

    Full Text Available Our brains readily decode facial movements and changes in social attention, reflected in earlier and larger N170 event-related potentials (ERPs to viewing gaze aversions vs. direct gaze in real faces (Puce et al. 2000. In contrast, gaze aversions in line-drawn faces do not produce these N170 differences (Rossi et al., 2014, suggesting that physical stimulus properties or experimental context may drive these effects. Here we investigated the role of stimulus-induced context on neurophysiological responses to dynamic gaze. Sixteen healthy adults viewed line-drawn and real faces, with dynamic eye aversion and direct gaze transitions, and control stimuli (scrambled arrays and checkerboards while continuous electroencephalographic (EEG activity was recorded. EEG data from 2 temporo-occipital clusters of 9 electrodes in each hemisphere where N170 activity is known to be maximal were selected for analysis. N170 peak amplitude and latency, and temporal dynamics from event-related spectral perturbations (ERSPs were measured in 16 healthy subjects. Real faces generated larger N170s for averted vs. direct gaze motion, however, N170s to real and direct gaze were as large as those to respective controls. N170 amplitude did not differ across line-drawn gaze changes. Overall, bilateral mean gamma power changes for faces relative to control stimuli occurred between 150-350 ms, potentially reflecting signal detection of facial motion.Our data indicate that experimental context does not drive N170 differences to viewed gaze changes. Low-level stimulus properties, such as the high sclera/iris contrast change in real eyes likely drive the N170 changes to viewed aversive movements.

  12. Social evolution. Oxytocin-gaze positive loop and the coevolution of human-dog bonds.

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    Nagasawa, Miho; Mitsui, Shouhei; En, Shiori; Ohtani, Nobuyo; Ohta, Mitsuaki; Sakuma, Yasuo; Onaka, Tatsushi; Mogi, Kazutaka; Kikusui, Takefumi

    2015-04-17

    Human-like modes of communication, including mutual gaze, in dogs may have been acquired during domestication with humans. We show that gazing behavior from dogs, but not wolves, increased urinary oxytocin concentrations in owners, which consequently facilitated owners' affiliation and increased oxytocin concentration in dogs. Further, nasally administered oxytocin increased gazing behavior in dogs, which in turn increased urinary oxytocin concentrations in owners. These findings support the existence of an interspecies oxytocin-mediated positive loop facilitated and modulated by gazing, which may have supported the coevolution of human-dog bonding by engaging common modes of communicating social attachment. Copyright © 2015, American Association for the Advancement of Science.

  13. Gaze direction effects on perceptions of upper limb kinesthetic coordinate system axes.

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    Darling, W G; Hondzinski, J M; Harper, J G

    2000-12-01

    The effects of varying gaze direction on perceptions of the upper limb kinesthetic coordinate system axes and of the median plane location were studied in nine subjects with no history of neuromuscular disorders. In two experiments, six subjects aligned the unseen forearm to the trunk-fixed anterior-posterior (a/p) axis and earth-fixed vertical while gazing at different visual targets using either head or eye motion to vary gaze direction in different conditions. Effects of support of the upper limb on perceptual errors were also tested in different conditions. Absolute constant errors and variable errors associated with forearm alignment to the trunk-fixed a/p axis and earth-fixed vertical were similar for different gaze directions whether the head or eyes were moved to control gaze direction. Such errors were decreased by support of the upper limb when aligning to the vertical but not when aligning to the a/p axis. Regression analysis showed that single trial errors in individual subjects were poorly correlated with gaze direction, but showed a dependence on shoulder angles for alignment to both axes. Thus, changes in position of the head and eyes do not influence perceptions of upper limb kinesthetic coordinate system axes. However, dependence of the errors on arm configuration suggests that such perceptions are generated from sensations of shoulder and elbow joint angle information. In a third experiment, perceptions of median plane location were tested by instructing four subjects to place the unseen right index fingertip directly in front of the sternum either by motion of the straight arm at the shoulder or by elbow flexion/extension with shoulder angle varied. Gaze angles were varied to the right and left by 0.5 radians to determine effects of gaze direction on such perceptions. These tasks were also carried out with subjects blind-folded and head orientation varied to test for effects of head orientation on perceptions of median plane location. Constant

  14. Embodied social robots trigger gaze following in real-time

    OpenAIRE

    Wiese, Eva; Weis, Patrick; Lofaro, Daniel

    2018-01-01

    In human-human interaction, we use information from gestures, facial expressions and gaze direction to make inferences about what interaction partners think, feel or intend to do next. Observing changes in gaze direction triggers shifts of attention to gazed-at locations and helps establish shared attention between gazer and observer - a prerequisite for more complex social skills like mentalizing, action understanding and joint action. The ability to follow others’ gaze develops early in lif...

  15. 3D recovery of human gaze in natural environments

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    Paletta, Lucas; Santner, Katrin; Fritz, Gerald; Mayer, Heinz

    2013-01-01

    The estimation of human attention has recently been addressed in the context of human robot interaction. Today, joint work spaces already exist and challenge cooperating systems to jointly focus on common objects, scenes and work niches. With the advent of Google glasses and increasingly affordable wearable eye-tracking, monitoring of human attention will soon become ubiquitous. The presented work describes for the first time a method for the estimation of human fixations in 3D environments that does not require any artificial landmarks in the field of view and enables attention mapping in 3D models. It enables full 3D recovery of the human view frustum and the gaze pointer in a previously acquired 3D model of the environment in real time. The study on the precision of this method reports a mean projection error ≈1.1 cm and a mean angle error ≈0.6° within the chosen 3D model - the precision does not go below the one of the technical instrument (≈1°). This innovative methodology will open new opportunities for joint attention studies as well as for bringing new potential into automated processing for human factors technologies.

  16. How do we update faces? Effects of gaze direction and facial expressions on working memory updating

    Directory of Open Access Journals (Sweden)

    Caterina eArtuso

    2012-09-01

    Full Text Available The aim of the study was to investigate how the biological binding between different facial dimensions, and their social and communicative relevance, may impact updating processes in working memory (WM. We focused on WM updating because it plays a key role in ongoing processing. Gaze direction and facial expression are crucial and changeable components of face processing. Direct gaze enhances the processing of approach-oriented facial emotional expressions (e.g. joy, while averted gaze enhances the processing of avoidance-oriented facial emotional expressions (e.g. fear. Thus, the way in which these two facial dimensions are combined communicates to the observer important behavioral and social information. Updating of these two facial dimensions and their bindings has not been investigated before, despite the fact that they provide a piece of social information essential for building and maintaining an internal ongoing representation of our social environment. In Experiment 1 we created a task in which the binding between gaze direction and facial expression was manipulated: high binding conditions (e.g. joy-direct gaze were compared to low binding conditions (e.g. joy-averted gaze. Participants had to study and update continuously a number of faces, displaying different bindings between the two dimensions. In Experiment 2 we tested whether updating was affected by the social and communicative value of the facial dimension binding; to this end, we manipulated bindings between eye and hair color, two less communicative facial dimensions. Two new results emerged. First, faster response times were found in updating combinations of facial dimensions highly bound together. Second, our data showed that the ease of the ongoing updating processing varied depending on the communicative meaning of the binding that had to be updated. The results are discussed with reference to the role of WM updating in social cognition and appraisal processes.

  17. How do we update faces? Effects of gaze direction and facial expressions on working memory updating.

    Science.gov (United States)

    Artuso, Caterina; Palladino, Paola; Ricciardelli, Paola

    2012-01-01

    The aim of the study was to investigate how the biological binding between different facial dimensions, and their social and communicative relevance, may impact updating processes in working memory (WM). We focused on WM updating because it plays a key role in ongoing processing. Gaze direction and facial expression are crucial and changeable components of face processing. Direct gaze enhances the processing of approach-oriented facial emotional expressions (e.g., joy), while averted gaze enhances the processing of avoidance-oriented facial emotional expressions (e.g., fear). Thus, the way in which these two facial dimensions are combined communicates to the observer important behavioral and social information. Updating of these two facial dimensions and their bindings has not been investigated before, despite the fact that they provide a piece of social information essential for building and maintaining an internal ongoing representation of our social environment. In Experiment 1 we created a task in which the binding between gaze direction and facial expression was manipulated: high binding conditions (e.g., joy-direct gaze) were compared to low binding conditions (e.g., joy-averted gaze). Participants had to study and update continuously a number of faces, displaying different bindings between the two dimensions. In Experiment 2 we tested whether updating was affected by the social and communicative value of the facial dimension binding; to this end, we manipulated bindings between eye and hair color, two less communicative facial dimensions. Two new results emerged. First, faster response times were found in updating combinations of facial dimensions highly bound together. Second, our data showed that the ease of the ongoing updating processing varied depending on the communicative meaning of the binding that had to be updated. The results are discussed with reference to the role of WM updating in social cognition and appraisal processes.

  18. Role of Gaze Cues in Interpersonal Motor Coordination: Towards Higher Affiliation in Human-Robot Interaction.

    Directory of Open Access Journals (Sweden)

    Mahdi Khoramshahi

    Full Text Available The ability to follow one another's gaze plays an important role in our social cognition; especially when we synchronously perform tasks together. We investigate how gaze cues can improve performance in a simple coordination task (i.e., the mirror game, whereby two players mirror each other's hand motions. In this game, each player is either a leader or follower. To study the effect of gaze in a systematic manner, the leader's role is played by a robotic avatar. We contrast two conditions, in which the avatar provides or not explicit gaze cues that indicate the next location of its hand. Specifically, we investigated (a whether participants are able to exploit these gaze cues to improve their coordination, (b how gaze cues affect action prediction and temporal coordination, and (c whether introducing active gaze behavior for avatars makes them more realistic and human-like (from the user point of view.43 subjects participated in 8 trials of the mirror game. Each subject performed the game in the two conditions (with and without gaze cues. In this within-subject study, the order of the conditions was randomized across participants, and subjective assessment of the avatar's realism was assessed by administering a post-hoc questionnaire. When gaze cues were provided, a quantitative assessment of synchrony between participants and the avatar revealed a significant improvement in subject reaction-time (RT. This confirms our hypothesis that gaze cues improve the follower's ability to predict the avatar's action. An analysis of the pattern of frequency across the two players' hand movements reveals that the gaze cues improve the overall temporal coordination across the two players. Finally, analysis of the subjective evaluations from the questionnaires reveals that, in the presence of gaze cues, participants found it not only more human-like/realistic, but also easier to interact with the avatar.This work confirms that people can exploit gaze cues to

  19. Human-like object tracking and gaze estimation with PKD android.

    Science.gov (United States)

    Wijayasinghe, Indika B; Miller, Haylie L; Das, Sumit K; Bugnariu, Nicoleta L; Popa, Dan O

    2016-05-01

    As the use of robots increases for tasks that require human-robot interactions, it is vital that robots exhibit and understand human-like cues for effective communication. In this paper, we describe the implementation of object tracking capability on Philip K. Dick (PKD) android and a gaze tracking algorithm, both of which further robot capabilities with regard to human communication. PKD's ability to track objects with human-like head postures is achieved with visual feedback from a Kinect system and an eye camera. The goal of object tracking with human-like gestures is twofold : to facilitate better human-robot interactions and to enable PKD as a human gaze emulator for future studies. The gaze tracking system employs a mobile eye tracking system (ETG; SensoMotoric Instruments) and a motion capture system (Cortex; Motion Analysis Corp.) for tracking the head orientations. Objects to be tracked are displayed by a virtual reality system, the Computer Assisted Rehabilitation Environment (CAREN; MotekForce Link). The gaze tracking algorithm converts eye tracking data and head orientations to gaze information facilitating two objectives: to evaluate the performance of the object tracking system for PKD and to use the gaze information to predict the intentions of the user, enabling the robot to understand physical cues by humans.

  20. Human-like object tracking and gaze estimation with PKD android

    Science.gov (United States)

    Wijayasinghe, Indika B.; Miller, Haylie L.; Das, Sumit K.; Bugnariu, Nicoleta L.; Popa, Dan O.

    2016-05-01

    As the use of robots increases for tasks that require human-robot interactions, it is vital that robots exhibit and understand human-like cues for effective communication. In this paper, we describe the implementation of object tracking capability on Philip K. Dick (PKD) android and a gaze tracking algorithm, both of which further robot capabilities with regard to human communication. PKD's ability to track objects with human-like head postures is achieved with visual feedback from a Kinect system and an eye camera. The goal of object tracking with human-like gestures is twofold: to facilitate better human-robot interactions and to enable PKD as a human gaze emulator for future studies. The gaze tracking system employs a mobile eye tracking system (ETG; SensoMotoric Instruments) and a motion capture system (Cortex; Motion Analysis Corp.) for tracking the head orientations. Objects to be tracked are displayed by a virtual reality system, the Computer Assisted Rehabilitation Environment (CAREN; MotekForce Link). The gaze tracking algorithm converts eye tracking data and head orientations to gaze information facilitating two objectives: to evaluate the performance of the object tracking system for PKD and to use the gaze information to predict the intentions of the user, enabling the robot to understand physical cues by humans.

  1. Influence of ethnic group-membership and gaze direction on the perception of emotions. A cross-cultural study between Germany and China.

    Science.gov (United States)

    Krämer, Katharina; Bente, Gary; Luo, Siyang; Pfeiffer, Ulrich J; Han, Shihui; Vogeley, Kai

    2013-01-01

    Emotional facial expressions provide important nonverbal cues in human interactions. The perception of emotions is not only influenced by a person's ethnic background but also depends on whether a person is engaged with the emotion-encoder. Although these factors are known to affect emotion perception, their impact has only been studied in isolation before. The aim of the present study was to investigate their combined influence. Thus, in order to study the influence of engagement on emotion perception between persons from different ethnicities, we compared participants from China and Germany. Asian-looking and European-looking virtual agents expressed anger and happiness while gazing at the participant or at another person. Participants had to assess the perceived valence of the emotional expressions. Results indicate that indeed two factors that are known to have a considerable influence on emotion perception interacted in their combined influence: We found that the perceived intensity of an emotion expressed by ethnic in-group members was in most cases independent of gaze direction, whereas gaze direction had an influence on the emotion perception of ethnic out-group members. Additionally, participants from the ethnic out-group tended to perceive emotions as more pronounced than participants from the ethnic in-group when they were directly gazed at. These findings suggest that gaze direction has a differential influence on ethnic in-group and ethnic out-group dynamics during emotion perception.

  2. Follow My Eyes: The Gaze of Politicians Reflexively Captures the Gaze of Ingroup Voters

    Science.gov (United States)

    Liuzza, Marco Tullio; Cazzato, Valentina; Vecchione, Michele; Crostella, Filippo; Caprara, Gian Vittorio; Aglioti, Salvatore Maria

    2011-01-01

    Studies in human and non-human primates indicate that basic socio-cognitive operations are inherently linked to the power of gaze in capturing reflexively the attention of an observer. Although monkey studies indicate that the automatic tendency to follow the gaze of a conspecific is modulated by the leader-follower social status, evidence for such effects in humans is meager. Here, we used a gaze following paradigm where the directional gaze of right- or left-wing Italian political characters could influence the oculomotor behavior of ingroup or outgroup voters. We show that the gaze of Berlusconi, the right-wing leader currently dominating the Italian political landscape, potentiates and inhibits gaze following behavior in ingroup and outgroup voters, respectively. Importantly, the higher the perceived similarity in personality traits between voters and Berlusconi, the stronger the gaze interference effect. Thus, higher-order social variables such as political leadership and affiliation prepotently affect reflexive shifts of attention. PMID:21957479

  3. The effect of arousal and eye gaze direction on trust evaluations of stranger's faces: A potential pathway to paranoid thinking.

    Science.gov (United States)

    Abbott, Jennie; Middlemiss, Megan; Bruce, Vicki; Smailes, David; Dudley, Robert

    2018-09-01

    When asked to evaluate faces of strangers, people with paranoia show a tendency to rate others as less trustworthy. The present study investigated the impact of arousal on this interpersonal bias, and whether this bias was specific to evaluations of trust or additionally affected other trait judgements. The study also examined the impact of eye gaze direction, as direct eye gaze has been shown to heighten arousal. In two experiments, non-clinical participants completed face rating tasks before and after either an arousal manipulation or control manipulation. Experiment one examined the effects of heightened arousal on judgements of trustworthiness. Experiment two examined the specificity of the bias, and the impact of gaze direction. Experiment one indicated that the arousal manipulation led to lower trustworthiness ratings. Experiment two showed that heightened arousal reduced trust evaluations of trustworthy faces, particularly trustworthy faces with averted gaze. The control group rated trustworthy faces with direct gaze as more trustworthy post-manipulation. There was some evidence that attractiveness ratings were affected similarly to the trust judgements, whereas judgements of intelligence were not affected by higher arousal. In both studies, participants reported low levels of arousal even after the manipulation and the use of a non-clinical sample limits the generalisability to clinical samples. There is a complex interplay between arousal, evaluations of trustworthiness and gaze direction. Heightened arousal influences judgements of trustworthiness, but within the context of face type and gaze direction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. How does image noise affect actual and predicted human gaze allocation in assessing image quality?

    Science.gov (United States)

    Röhrbein, Florian; Goddard, Peter; Schneider, Michael; James, Georgina; Guo, Kun

    2015-07-01

    A central research question in natural vision is how to allocate fixation to extract informative cues for scene perception. With high quality images, psychological and computational studies have made significant progress to understand and predict human gaze allocation in scene exploration. However, it is unclear whether these findings can be generalised to degraded naturalistic visual inputs. In this eye-tracking and computational study, we methodically distorted both man-made and natural scenes with Gaussian low-pass filter, circular averaging filter and Additive Gaussian white noise, and monitored participants' gaze behaviour in assessing perceived image qualities. Compared with original high quality images, distorted images attracted fewer numbers of fixations but longer fixation durations, shorter saccade distance and stronger central fixation bias. This impact of image noise manipulation on gaze distribution was mainly determined by noise intensity rather than noise type, and was more pronounced for natural scenes than for man-made scenes. We furthered compared four high performing visual attention models in predicting human gaze allocation in degraded scenes, and found that model performance lacked human-like sensitivity to noise type and intensity, and was considerably worse than human performance measured as inter-observer variance. Furthermore, the central fixation bias is a major predictor for human gaze allocation, which becomes more prominent with increased noise intensity. Our results indicate a crucial role of external noise intensity in determining scene-viewing gaze behaviour, which should be considered in the development of realistic human-vision-inspired attention models. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Gaze-and-brain-controlled interfaces for human-computer and human-robot interaction

    Directory of Open Access Journals (Sweden)

    Shishkin S. L.

    2017-09-01

    Full Text Available Background. Human-machine interaction technology has greatly evolved during the last decades, but manual and speech modalities remain single output channels with their typical constraints imposed by the motor system’s information transfer limits. Will brain-computer interfaces (BCIs and gaze-based control be able to convey human commands or even intentions to machines in the near future? We provide an overview of basic approaches in this new area of applied cognitive research. Objective. We test the hypothesis that the use of communication paradigms and a combination of eye tracking with unobtrusive forms of registering brain activity can improve human-machine interaction. Methods and Results. Three groups of ongoing experiments at the Kurchatov Institute are reported. First, we discuss the communicative nature of human-robot interaction, and approaches to building a more e cient technology. Specifically, “communicative” patterns of interaction can be based on joint attention paradigms from developmental psychology, including a mutual “eye-to-eye” exchange of looks between human and robot. Further, we provide an example of “eye mouse” superiority over the computer mouse, here in emulating the task of selecting a moving robot from a swarm. Finally, we demonstrate a passive, noninvasive BCI that uses EEG correlates of expectation. This may become an important lter to separate intentional gaze dwells from non-intentional ones. Conclusion. The current noninvasive BCIs are not well suited for human-robot interaction, and their performance, when they are employed by healthy users, is critically dependent on the impact of the gaze on selection of spatial locations. The new approaches discussed show a high potential for creating alternative output pathways for the human brain. When support from passive BCIs becomes mature, the hybrid technology of the eye-brain-computer (EBCI interface will have a chance to enable natural, fluent, and the

  6. The neurophysiology of human touch and eye gaze and its effects on therapeutic relationships and healing: a scoping review protocol.

    Science.gov (United States)

    Kerr, Fiona; Wiechula, Rick; Feo, Rebecca; Schultz, Tim; Kitson, Alison

    2016-04-01

    The objective of this scoping review is to examine and map the range of neurophysiological impacts of human touch and eye gaze, and better understand their possible links to the therapeutic relationship and the process of healing. The specific question is "what neurophysiological impacts of human touch and eye gaze have been reported in relation to therapeutic relationships and healing?"

  7. Ultra-low-cost 3D gaze estimation: an intuitive high information throughput compliment to direct brain-machine interfaces

    Science.gov (United States)

    Abbott, W. W.; Faisal, A. A.

    2012-08-01

    Eye movements are highly correlated with motor intentions and are often retained by patients with serious motor deficiencies. Despite this, eye tracking is not widely used as control interface for movement in impaired patients due to poor signal interpretation and lack of control flexibility. We propose that tracking the gaze position in 3D rather than 2D provides a considerably richer signal for human machine interfaces by allowing direct interaction with the environment rather than via computer displays. We demonstrate here that by using mass-produced video-game hardware, it is possible to produce an ultra-low-cost binocular eye-tracker with comparable performance to commercial systems, yet 800 times cheaper. Our head-mounted system has 30 USD material costs and operates at over 120 Hz sampling rate with a 0.5-1 degree of visual angle resolution. We perform 2D and 3D gaze estimation, controlling a real-time volumetric cursor essential for driving complex user interfaces. Our approach yields an information throughput of 43 bits s-1, more than ten times that of invasive and semi-invasive brain-machine interfaces (BMIs) that are vastly more expensive. Unlike many BMIs our system yields effective real-time closed loop control of devices (10 ms latency), after just ten minutes of training, which we demonstrate through a novel BMI benchmark—the control of the video arcade game ‘Pong’.

  8. Sociability and gazing toward humans in dogs and wolves: Simple behaviors with broad implications.

    Science.gov (United States)

    Bentosela, Mariana; Wynne, C D L; D'Orazio, M; Elgier, A; Udell, M A R

    2016-01-01

    Sociability, defined as the tendency to approach and interact with unfamiliar people, has been found to modulate some communicative responses in domestic dogs, including gaze behavior toward the human face. The objective of this study was to compare sociability and gaze behavior in pet domestic dogs and in human-socialized captive wolves in order to identify the relative influence of domestication and learning in the development of the dog-human bond. In Experiment 1, we assessed the approach behavior and social tendencies of dogs and wolves to a familiar and an unfamiliar person. In Experiment 2, we compared the animal's duration of gaze toward a person's face in the presence of food, which the animals could see but not access. Dogs showed higher levels of interspecific sociability than wolves in all conditions, including those where attention was unavailable. In addition, dogs gazed longer at the person's face than wolves in the presence of out-of-reach food. The potential contributions of domestication, associative learning, and experiences during ontogeny to prosocial behavior toward humans are discussed. © 2016 Society for the Experimental Analysis of Behavior.

  9. I Reach Faster When I See You Look: Gaze Effects in Human-Human and Human-Robot Face-to-Face Cooperation.

    Science.gov (United States)

    Boucher, Jean-David; Pattacini, Ugo; Lelong, Amelie; Bailly, Gerrard; Elisei, Frederic; Fagel, Sascha; Dominey, Peter Ford; Ventre-Dominey, Jocelyne

    2012-01-01

    Human-human interaction in natural environments relies on a variety of perceptual cues. Humanoid robots are becoming increasingly refined in their sensorimotor capabilities, and thus should now be able to manipulate and exploit these social cues in cooperation with their human partners. Previous studies have demonstrated that people follow human and robot gaze, and that it can help them to cope with spatially ambiguous language. Our goal is to extend these findings into the domain of action, to determine how human and robot gaze can influence the speed and accuracy of human action. We report on results from a human-human cooperation experiment demonstrating that an agent's vision of her/his partner's gaze can significantly improve that agent's performance in a cooperative task. We then implement a heuristic capability to generate such gaze cues by a humanoid robot that engages in the same cooperative interaction. The subsequent human-robot experiments demonstrate that a human agent can indeed exploit the predictive gaze of their robot partner in a cooperative task. This allows us to render the humanoid robot more human-like in its ability to communicate with humans. The long term objectives of the work are thus to identify social cooperation cues, and to validate their pertinence through implementation in a cooperative robot. The current research provides the robot with the capability to produce appropriate speech and gaze cues in the context of human-robot cooperation tasks. Gaze is manipulated in three conditions: Full gaze (coordinated eye and head), eyes hidden with sunglasses, and head fixed. We demonstrate the pertinence of these cues in terms of statistical measures of action times for humans in the context of a cooperative task, as gaze significantly facilitates cooperation as measured by human response times.

  10. Testing the dual-route model of perceived gaze direction: Linear combination of eye and head cues.

    Science.gov (United States)

    Otsuka, Yumiko; Mareschal, Isabelle; Clifford, Colin W G

    2016-06-01

    We have recently proposed a dual-route model of the effect of head orientation on perceived gaze direction (Otsuka, Mareschal, Calder, & Clifford, 2014; Otsuka, Mareschal, & Clifford, 2015), which computes perceived gaze direction as a linear combination of eye orientation and head orientation. By parametrically manipulating eye orientation and head orientation, we tested the adequacy of a linear model to account for the effect of horizontal head orientation on perceived direction of gaze. Here, participants adjusted an on-screen pointer toward the perceived gaze direction in two image conditions: Normal condition and Wollaston condition. Images in the Normal condition included a change in the visible part of the eye along with the change in head orientation, while images in the Wollaston condition were manipulated to have identical eye regions across head orientations. Multiple regression analysis with explanatory variables of eye orientation and head orientation revealed that linear models account for most of the variance both in the Normal condition and in the Wollaston condition. Further, we found no evidence that the model with a nonlinear term explains significantly more variance. Thus, the current study supports the dual-route model that computes the perceived gaze direction as a linear combination of eye orientation and head orientation.

  11. Exploring associations between gaze patterns and putative human mirror neuron system activity.

    Science.gov (United States)

    Donaldson, Peter H; Gurvich, Caroline; Fielding, Joanne; Enticott, Peter G

    2015-01-01

    The human mirror neuron system (MNS) is hypothesized to be crucial to social cognition. Given that key MNS-input regions such as the superior temporal sulcus are involved in biological motion processing, and mirror neuron activity in monkeys has been shown to vary with visual attention, aberrant MNS function may be partly attributable to atypical visual input. To examine the relationship between gaze pattern and interpersonal motor resonance (IMR; an index of putative MNS activity), healthy right-handed participants aged 18-40 (n = 26) viewed videos of transitive grasping actions or static hands, whilst the left primary motor cortex received transcranial magnetic stimulation. Motor-evoked potentials recorded in contralateral hand muscles were used to determine IMR. Participants also underwent eyetracking analysis to assess gaze patterns whilst viewing the same videos. No relationship was observed between predictive gaze and IMR. However, IMR was positively associated with fixation counts in areas of biological motion in the videos, and negatively associated with object areas. These findings are discussed with reference to visual influences on the MNS, and the possibility that MNS atypicalities might be influenced by visual processes such as aberrant gaze pattern.

  12. Exploring associations between gaze patterns and putative human mirror neuron system activity

    Directory of Open Access Journals (Sweden)

    Peter Hugh Donaldson

    2015-07-01

    Full Text Available The human mirror neuron system (MNS is hypothesised to be crucial to social cognition. Given that key MNS-input regions such as the superior temporal sulcus are involved in biological motion processing, and mirror neuron activity in monkeys has been shown to vary with visual attention, aberrant MNS function may be partly attributable to atypical visual input. To examine the relationship between gaze pattern and interpersonal motor resonance (IMR; an index of putative MNS activity, healthy right-handed participants aged 18-40 (n = 26 viewed videos of transitive grasping actions or static hands, whilst the left primary motor cortex received transcranial magnetic stimulation (TMS. Motor-evoked potentials (MEPs recorded in contralateral hand muscles were used to determine IMR. Participants also underwent eyetracking analysis to assess gaze patterns whilst viewing the same videos. No relationship was observed between predictive gaze (PG and IMR. However, IMR was positively associated with fixation counts in areas of biological motion in the videos, and negatively associated with object areas. These findings are discussed with reference to visual influences on the MNS, and the possibility that MNS atypicalities might be influenced by visual processes such as aberrant gaze pattern.

  13. Gaze-Following and Reaction to an Aversive Social Interaction Have Corresponding Associations with Variation in the OXTR Gene in Dogs but Not in Human Infants.

    Science.gov (United States)

    Oláh, Katalin; Topál, József; Kovács, Krisztina; Kis, Anna; Koller, Dóra; Young Park, Soon; Virányi, Zsófia

    2017-01-01

    It has been suggested that dogs' remarkable capacity to use human communicative signals lies in their comparable social cognitive skills; however, this view has been questioned recently. The present study investigated associations between oxytocin receptor gene (OXTR) polymorphisms and social behavior in human infants and dogs with the aim to unravel potentially differential mechanisms behind their responsiveness to human gaze. Sixteen-month-old human infants ( N = 99) and adult Border Collie dogs ( N = 71) participated in two tasks designed to test (1) their use of gaze-direction as a cue to locate a hidden object, and (2) their reactions to an aversive social interaction (using the still face task for children and a threatening approach task for dogs). Moreover, we obtained DNA samples to analyze associations between single nucleotide polymorphisms (SNP) in the OXTR (dogs: -213AG, -94TC, -74CG, rs8679682, children: rs53576, rs1042778, rs2254298) and behavior. We found that OXTR genotype was significantly associated with reactions to an aversive social interaction both in dogs and children, confirming the anxiolytic effect of oxytocin in both species. In dogs, the genotypes linked to less fearful behavior were associated also with a higher willingness to follow gaze whereas in children, OXTR gene polymorphisms did not affect gaze following success. This pattern of gene-behavior associations suggests that for dogs the two situations are more alike (potentially fear-inducing or competitive) than for human children. This raises the possibility that, in contrast to former studies proposing human-like cooperativeness in dogs, dogs may perceive human gaze in an object-choice task in a more antagonistic manner than children.

  14. Gaze-Following and Reaction to an Aversive Social Interaction Have Corresponding Associations with Variation in the OXTR Gene in Dogs but Not in Human Infants

    Directory of Open Access Journals (Sweden)

    Katalin Oláh

    2017-12-01

    Full Text Available It has been suggested that dogs' remarkable capacity to use human communicative signals lies in their comparable social cognitive skills; however, this view has been questioned recently. The present study investigated associations between oxytocin receptor gene (OXTR polymorphisms and social behavior in human infants and dogs with the aim to unravel potentially differential mechanisms behind their responsiveness to human gaze. Sixteen-month-old human infants (N = 99 and adult Border Collie dogs (N = 71 participated in two tasks designed to test (1 their use of gaze-direction as a cue to locate a hidden object, and (2 their reactions to an aversive social interaction (using the still face task for children and a threatening approach task for dogs. Moreover, we obtained DNA samples to analyze associations between single nucleotide polymorphisms (SNP in the OXTR (dogs: −213AG, −94TC, −74CG, rs8679682, children: rs53576, rs1042778, rs2254298 and behavior. We found that OXTR genotype was significantly associated with reactions to an aversive social interaction both in dogs and children, confirming the anxiolytic effect of oxytocin in both species. In dogs, the genotypes linked to less fearful behavior were associated also with a higher willingness to follow gaze whereas in children, OXTR gene polymorphisms did not affect gaze following success. This pattern of gene-behavior associations suggests that for dogs the two situations are more alike (potentially fear-inducing or competitive than for human children. This raises the possibility that, in contrast to former studies proposing human-like cooperativeness in dogs, dogs may perceive human gaze in an object-choice task in a more antagonistic manner than children.

  15. Gaze perception in social anxiety and social anxiety disorder

    Directory of Open Access Journals (Sweden)

    Lars eSchulze

    2013-12-01

    Full Text Available Clinical observations suggest abnormal gaze perception to be an important indicator of social anxiety disorder (SAD. Experimental research has yet paid relatively little attention to the study of gaze perception in SAD. In this article we first discuss gaze perception in healthy human beings before reviewing self-referential and threat-related biases of gaze perception in clinical and non-clinical socially anxious samples. Relative to controls, socially anxious individuals exhibit an enhanced self-directed perception of gaze directions and demonstrate a pronounced fear of direct eye contact, though findings are less consistent regarding the avoidance of mutual gaze in SAD. Prospects for future research and clinical implications are discussed.

  16. Directing gaze: the effect of disclaimer labels on women's visual attention to fashion magazine advertisements.

    Science.gov (United States)

    Bury, Belinda; Tiggemann, Marika; Slater, Amy

    2014-09-01

    In an effort to combat the known negative effects of exposure to unrealistic thin ideal images, there is increasing worldwide pressure on fashion, media and advertising industries to disclose when images have been digitally altered. The current study used eye tracking technology to investigate experimentally how digital alteration disclaimer labels impact women's visual attention to fashion magazine advertisements. Participants were 60 female undergraduate students who viewed four thin ideal advertisements with either no disclaimer, a generic disclaimer, or a specific more detailed disclaimer. It was established that women did attend to the disclaimers. The nature of the disclaimer had no effect on time spent looking at particular body parts, but did affect the direction of gaze following reading of the disclaimer. This latter effect was found to be greater for women high on trait appearance comparison. Further research is paramount in guiding effective policy around the use of disclaimer labels. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Effects of Facial Symmetry and Gaze Direction on Perception of Social Attributes: A Study in Experimental Art History

    OpenAIRE

    Folger?, Per O.; Hodne, Lasse; Johansson, Christer; Andresen, Alf E.; S?tren, Lill C.; Specht, Karsten; Skaar, ?ystein O.; Reber, Rolf

    2016-01-01

    This article explores the possibility of testing hypotheses about art production in the past by collecting data in the present. We call this enterprise “experimental art history”. Why did medieval artists prefer to paint Christ with his face directed towards the beholder, while profane faces were noticeably more often painted in different degrees of profile? Is a preference for frontal faces motivated by deeper evolutionary and biological considerations? Head and gaze direction is a significa...

  18. Cortical Activation during Landmark-Centered vs. Gaze-Centered Memory of Saccade Targets in the Human: An FMRI Study

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    Ying Chen

    2017-06-01

    Full Text Available A remembered saccade target could be encoded in egocentric coordinates such as gaze-centered, or relative to some external allocentric landmark that is independent of the target or gaze (landmark-centered. In comparison to egocentric mechanisms, very little is known about such a landmark-centered representation. Here, we used an event-related fMRI design to identify brain areas supporting these two types of spatial coding (i.e., landmark-centered vs. gaze-centered for target memory during the Delay phase where only target location, not saccade direction, was specified. The paradigm included three tasks with identical display of visual stimuli but different auditory instructions: Landmark Saccade (remember target location relative to a visual landmark, independent of gaze, Control Saccade (remember original target location relative to gaze fixation, independent of the landmark, and a non-spatial control, Color Report (report target color. During the Delay phase, the Control and Landmark Saccade tasks activated overlapping areas in posterior parietal cortex (PPC and frontal cortex as compared to the color control, but with higher activation in PPC for target coding in the Control Saccade task and higher activation in temporal and occipital cortex for target coding in Landmark Saccade task. Gaze-centered directional selectivity was observed in superior occipital gyrus and inferior occipital gyrus, whereas landmark-centered directional selectivity was observed in precuneus and midposterior intraparietal sulcus. During the Response phase after saccade direction was specified, the parietofrontal network in the left hemisphere showed higher activation for rightward than leftward saccades. Our results suggest that cortical activation for coding saccade target direction relative to a visual landmark differs from gaze-centered directional selectivity for target memory, from the mechanisms for other types of allocentric tasks, and from the directionally

  19. Training for eye contact modulates gaze following in dogs.

    Science.gov (United States)

    Wallis, Lisa J; Range, Friederike; Müller, Corsin A; Serisier, Samuel; Huber, Ludwig; Virányi, Zsófia

    2015-08-01

    Following human gaze in dogs and human infants can be considered a socially facilitated orientation response, which in object choice tasks is modulated by human-given ostensive cues. Despite their similarities to human infants, and extensive skills in reading human cues in foraging contexts, no evidence that dogs follow gaze into distant space has been found. We re-examined this question, and additionally whether dogs' propensity to follow gaze was affected by age and/or training to pay attention to humans. We tested a cross-sectional sample of 145 border collies aged 6 months to 14 years with different amounts of training over their lives. The dogs' gaze-following response in test and control conditions before and after training for initiating eye contact with the experimenter was compared with that of a second group of 13 border collies trained to touch a ball with their paw. Our results provide the first evidence that dogs can follow human gaze into distant space. Although we found no age effect on gaze following, the youngest and oldest age groups were more distractible, which resulted in a higher number of looks in the test and control conditions. Extensive lifelong formal training as well as short-term training for eye contact decreased dogs' tendency to follow gaze and increased their duration of gaze to the face. The reduction in gaze following after training for eye contact cannot be explained by fatigue or short-term habituation, as in the second group gaze following increased after a different training of the same length. Training for eye contact created a competing tendency to fixate the face, which prevented the dogs from following the directional cues. We conclude that following human gaze into distant space in dogs is modulated by training, which may explain why dogs perform poorly in comparison to other species in this task.

  20. Extended Fitts' model of pointing time in eye-gaze input system - Incorporating effects of target shape and movement direction into modeling.

    Science.gov (United States)

    Murata, Atsuo; Fukunaga, Daichi

    2018-04-01

    This study attempted to investigate the effects of the target shape and the movement direction on the pointing time using an eye-gaze input system and extend Fitts' model so that these factors are incorporated into the model and the predictive power of Fitts' model is enhanced. The target shape, the target size, the movement distance, and the direction of target presentation were set as within-subject experimental variables. The target shape included: a circle, and rectangles with an aspect ratio of 1:1, 1:2, 1:3, and 1:4. The movement direction included eight directions: upper, lower, left, right, upper left, upper right, lower left, and lower right. On the basis of the data for identifying the effects of the target shape and the movement direction on the pointing time, an attempt was made to develop a generalized and extended Fitts' model that took into account the movement direction and the target shape. As a result, the generalized and extended model was found to fit better to the experimental data, and be more effective for predicting the pointing time for a variety of human-computer interaction (HCI) task using an eye-gaze input system. Copyright © 2017. Published by Elsevier Ltd.

  1. Baby schema in human and animal faces induces cuteness perception and gaze allocation in children

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    Marta eBorgi

    2014-05-01

    Full Text Available The baby schema concept was originally proposed as a set of infantile traits with high appeal for humans, subsequently shown to elicit caretaking behavior and to affect cuteness perception and attentional processes. However, it is unclear whether the response to the baby schema may be extended to the human-animal bond context. Moreover, questions remain as to whether the cute response is constant and persistent or whether it changes with development. In the present study we parametrically manipulated the baby schema in images of humans, dogs and cats. We analyzed responses of 3-6-year-old children, using both explicit (i.e. cuteness ratings and implicit (i.e. eye gaze patterns measures. By means of eye-tracking, we assessed children’s preferential attention to images varying only for the degree of baby schema and explored participants’ fixation patterns during a cuteness task. For comparative purposes, cuteness ratings were also obtained in a sample of adults. Overall our results show that the response to an infantile facial configuration emerges early during development. In children, the baby schema affects both cuteness perception and gaze allocation to infantile stimuli and to specific facial features, an effect not simply limited to human faces. In line with previous research, results confirm human positive appraisal towards animals and inform both educational and therapeutic interventions involving pets, helping to minimize risk factors (e.g. dog bites.

  2. Interactive effects between gaze direction and facial expression on attentional resources deployment: the task instruction and context matter

    Science.gov (United States)

    Ricciardelli, Paola; Lugli, Luisa; Pellicano, Antonello; Iani, Cristina; Nicoletti, Roberto

    2016-01-01

    In three experiments, we tested whether the amount of attentional resources needed to process a face displaying neutral/angry/fearful facial expressions with direct or averted gaze depends on task instructions, and face presentation. To this end, we used a Rapid Serial Visual Presentation paradigm in which participants in Experiment 1 were first explicitly asked to discriminate whether the expression of a target face (T1) with direct or averted gaze was angry or neutral, and then to judge the orientation of a landscape (T2). Experiment 2 was identical to Experiment 1 except that participants had to discriminate the gender of the face of T1 and fearful faces were also presented randomly inter-mixed within each block of trials. Experiment 3 differed from Experiment 2 only because angry and fearful faces were never presented within the same block. The findings indicated that the presence of the attentional blink (AB) for face stimuli depends on specific combinations of gaze direction and emotional facial expressions and crucially revealed that the contextual factors (e.g., explicit instruction to process the facial expression and the presence of other emotional faces) can modify and even reverse the AB, suggesting a flexible and more contextualized deployment of attentional resources in face processing. PMID:26898473

  3. Right Hemispheric Dominance in Gaze-Triggered Reflexive Shift of Attention in Humans

    Science.gov (United States)

    Okada, Takashi; Sato, Wataru; Toichi, Motomi

    2006-01-01

    Recent findings suggest a right hemispheric dominance in gaze-triggered shifts of attention. The aim of this study was to clarify the dominant hemisphere in the gaze processing that mediates attentional shift. A target localization task, with preceding non-predicative gaze cues presented to each visual field, was undertaken by 44 healthy subjects,…

  4. The influence of banner advertisements on attention and memory: human faces with averted gaze can enhance advertising effectiveness.

    Science.gov (United States)

    Sajjacholapunt, Pitch; Ball, Linden J

    2014-01-01

    Research suggests that banner advertisements used in online marketing are often overlooked, especially when positioned horizontally on webpages. Such inattention invariably gives rise to an inability to remember advertising brands and messages, undermining the effectiveness of this marketing method. Recent interest has focused on whether human faces within banner advertisements can increase attention to the information they contain, since the gaze cues conveyed by faces can influence where observers look. We report an experiment that investigated the efficacy of faces located in banner advertisements to enhance the attentional processing and memorability of banner contents. We tracked participants' eye movements when they examined webpages containing either bottom-right vertical banners or bottom-center horizontal banners. We also manipulated facial information such that banners either contained no face, a face with mutual gaze or a face with averted gaze. We additionally assessed people's memories for brands and advertising messages. Results indicated that relative to other conditions, the condition involving faces with averted gaze increased attention to the banner overall, as well as to the advertising text and product. Memorability of the brand and advertising message was also enhanced. Conversely, in the condition involving faces with mutual gaze, the focus of attention was localized more on the face region rather than on the text or product, weakening any memory benefits for the brand and advertising message. This detrimental impact of mutual gaze on attention to advertised products was especially marked for vertical banners. These results demonstrate that the inclusion of human faces with averted gaze in banner advertisements provides a promising means for marketers to increase the attention paid to such adverts, thereby enhancing memory for advertising information.

  5. The influence of banner advertisements on attention and memory: Human faces with averted gaze can enhance advertising effectiveness

    Directory of Open Access Journals (Sweden)

    Pitch eSajjacholapunt

    2014-03-01

    Full Text Available Research suggests that banner advertisements used in online marketing are often overlooked, especially when positioned horizontally on webpages. Such inattention invariably gives rise to an inability to remember advertising brands and messages, undermining the effectiveness of this marketing method. Recent interest has focused on whether human faces within banner advertisements can increase attention to the information they contain, since the gaze cues conveyed by faces can influence where observers look. We report an experiment that investigated the efficacy of faces located in banner advertisements to enhance the attentional processing and memorability of banner contents. We tracked participants’ eye movements when they examined webpages containing either bottom-right vertical banners or bottom-centre horizontal banners. We also manipulated facial information such that banners either contained no face, a face with mutual gaze or a face with averted gaze. We additionally assessed people’s memories for brands and advertising messages. Results indicated that relative to other conditions, the condition involving faces with averted gaze increased attention to the banner overall, as well as to the advertising text and product. Memorability of the brand and advertising message was also enhanced. Conversely, in the condition involving faces with mutual gaze, the focus of attention was localised more on the face region rather than on the text or product, weakening any memory benefits for the brand and advertising message. This detrimental impact of mutual gaze on attention to advertised products was especially marked for vertical banners. These results demonstrate that the inclusion of human faces with averted gaze in banner advertisements provides a promising means for marketers to increase the attention paid to such adverts, thereby enhancing memory for advertising information.

  6. In the presence of conflicting gaze cues, fearful expression and eye-size guide attention.

    Science.gov (United States)

    Carlson, Joshua M; Aday, Jacob

    2017-10-19

    Humans are social beings that often interact in multi-individual environments. As such, we are frequently confronted with nonverbal social signals, including eye-gaze direction, from multiple individuals. Yet, the factors that allow for the prioritisation of certain gaze cues over others are poorly understood. Using a modified conflicting gaze paradigm, we tested the hypothesis that fearful gaze would be favoured amongst competing gaze cues. We further hypothesised that this effect is related to the increased sclera exposure, which is characteristic of fearful expressions. Across three experiments, we found that fearful, but not happy, gaze guides observers' attention over competing non-emotional gaze. The guidance of attention by fearful gaze appears to be linked to increased sclera exposure. However, differences in sclera exposure do not prioritise competing gazes of other types. Thus, fearful gaze guides attention among competing cues and this effect is facilitated by increased sclera exposure - but increased sclera exposure per se does not guide attention. The prioritisation of fearful gaze over non-emotional gaze likely represents an adaptive means of selectively attending to survival-relevant spatial locations.

  7. The response of guide dogs and pet dogs (Canis familiaris) to cues of human referential communication (pointing and gaze).

    Science.gov (United States)

    Ittyerah, Miriam; Gaunet, Florence

    2009-03-01

    The study raises the question of whether guide dogs and pet dogs are expected to differ in response to cues of referential communication given by their owners; especially since guide dogs grow up among sighted humans, and while living with their blind owners, they still have interactions with several sighted people. Guide dogs and pet dogs were required to respond to point, point and gaze, gaze and control cues of referential communication given by their owners. Results indicate that the two groups of dogs do not differ from each other, revealing that the visual status of the owner is not a factor in the use of cues of referential communication. Both groups of dogs have higher frequencies of performance and faster latencies for the point and the point and gaze cues as compared to gaze cue only. However, responses to control cues are below chance performance for the guide dogs, whereas the pet dogs perform at chance. The below chance performance of the guide dogs may be explained by a tendency among them to go and stand by the owner. The study indicates that both groups of dogs respond similarly in normal daily dyadic interaction with their owners and the lower comprehension of the human gaze may be a less salient cue among dogs in comparison to the pointing gesture.

  8. Gaze-related mimic word activates the frontal eye field and related network in the human brain: an fMRI study.

    Science.gov (United States)

    Osaka, Naoyuki; Osaka, Mariko

    2009-09-18

    This is an fMRI study demonstrating new evidence that a mimic word highly suggestive of an eye gaze, heard by the ear, significantly activates the frontal eye field (FEF), inferior frontal gyrus (IFG), dorsolateral premotor area (PMdr) and superior parietal lobule (SPL) connected with the frontal-parietal network. However, hearing a non-sense words that did not imply gaze under the same task does not activate this area in humans. We concluded that the FEF would be a critical area for generating/processing an active gaze, evoked by an onomatopoeia word that implied gaze closely associated with social skill. We suggest that the implied active gaze may depend on prefrontal-parietal interactions that modify cognitive gaze led by spatial visual attention associated with the SPL.

  9. Facial Expressions Modulate the Ontogenetic Trajectory of Gaze-Following among Monkeys

    Science.gov (United States)

    Teufel, Christoph; Gutmann, Anke; Pirow, Ralph; Fischer, Julia

    2010-01-01

    Gaze-following, the tendency to direct one's attention to locations looked at by others, is a crucial aspect of social cognition in human and nonhuman primates. Whereas the development of gaze-following has been intensely studied in human infants, its early ontogeny in nonhuman primates has received little attention. Combining longitudinal and…

  10. Assessing the precision of gaze following using a stereoscopic 3D virtual reality setting.

    Science.gov (United States)

    Atabaki, Artin; Marciniak, Karolina; Dicke, Peter W; Thier, Peter

    2015-07-01

    Despite the ecological importance of gaze following, little is known about the underlying neuronal processes, which allow us to extract gaze direction from the geometric features of the eye and head of a conspecific. In order to understand the neuronal mechanisms underlying this ability, a careful description of the capacity and the limitations of gaze following at the behavioral level is needed. Previous studies of gaze following, which relied on naturalistic settings have the disadvantage of allowing only very limited control of potentially relevant visual features guiding gaze following, such as the contrast of iris and sclera, the shape of the eyelids and--in the case of photographs--they lack depth. Hence, in order to get full control of potentially relevant features we decided to study gaze following of human observers guided by the gaze of a human avatar seen stereoscopically. To this end we established a stereoscopic 3D virtual reality setup, in which we tested human subjects' abilities to detect at which target a human avatar was looking at. Following the gaze of the avatar showed all the features of the gaze following of a natural person, namely a substantial degree of precision associated with a consistent pattern of systematic deviations from the target. Poor stereo vision affected performance surprisingly little (only in certain experimental conditions). Only gaze following guided by targets at larger downward eccentricities exhibited a differential effect of the presence or absence of accompanying movements of the avatar's eyelids and eyebrows. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Toward understanding social cues and signals in human-robot interaction: effects of robot gaze and proxemic behavior.

    Science.gov (United States)

    Fiore, Stephen M; Wiltshire, Travis J; Lobato, Emilio J C; Jentsch, Florian G; Huang, Wesley H; Axelrod, Benjamin

    2013-01-01

    As robots are increasingly deployed in settings requiring social interaction, research is needed to examine the social signals perceived by humans when robots display certain social cues. In this paper, we report a study designed to examine how humans interpret social cues exhibited by robots. We first provide a brief overview of perspectives from social cognition in humans and how these processes are applicable to human-robot interaction (HRI). We then discuss the need to examine the relationship between social cues and signals as a function of the degree to which a robot is perceived as a socially present agent. We describe an experiment in which social cues were manipulated on an iRobot Ava(TM) mobile robotics platform in a hallway navigation scenario. Cues associated with the robot's proxemic behavior were found to significantly affect participant perceptions of the robot's social presence and emotional state while cues associated with the robot's gaze behavior were not found to be significant. Further, regardless of the proxemic behavior, participants attributed more social presence and emotional states to the robot over repeated interactions than when they first interacted with it. Generally, these results indicate the importance for HRI research to consider how social cues expressed by a robot can differentially affect perceptions of the robot's mental states and intentions. The discussion focuses on implications for the design of robotic systems and future directions for research on the relationship between social cues and signals.

  12. Towards understanding social cues and signals in human-robot interaction: Effects of robot gaze and proxemic behavior

    Directory of Open Access Journals (Sweden)

    Stephen M. Fiore

    2013-11-01

    Full Text Available As robots are increasingly deployed in settings requiring social interaction, research is needed to examine the social signals perceived by humans when robots display certain social cues. In this paper, we report a study designed to examine how humans interpret social cues exhibited by robots. We first provide a brief overview of perspectives from social cognition in humans and how these processes are applicable to human-robot interaction (HRI. We then discuss the need to examine the relationship between social cues and signals as a function of the degree to which a robot is perceived as a socially present agent. We describe an experiment in which social cues were manipulated on an iRobot Ava™ Mobile Robotics Platform in a hallway navigation scenario. Cues associated with the robot’s proxemic behavior were found to significantly affect participant perceptions of the robot’s social presence and emotional state while cues associated with the robot’s gaze behavior were not found to be significant. Further, regardless of the proxemic behavior, participants attributed more social presence and emotional states to the robot over repeated interactions than when they first interacted with it. Generally, these results indicate the importance for HRI research to consider how social cues expressed by a robot can differentially affect perceptions of the robot’s mental states and intentions. The discussion focuses on implications for the design of robotic systems and future directions for research on the relationship between social cues and signals.

  13. I Reach Faster When I See You Look: Gaze Effects in Human–Human and Human–Robot Face-to-Face Cooperation

    Science.gov (United States)

    Boucher, Jean-David; Pattacini, Ugo; Lelong, Amelie; Bailly, Gerard; Elisei, Frederic; Fagel, Sascha; Dominey, Peter Ford; Ventre-Dominey, Jocelyne

    2012-01-01

    Human–human interaction in natural environments relies on a variety of perceptual cues. Humanoid robots are becoming increasingly refined in their sensorimotor capabilities, and thus should now be able to manipulate and exploit these social cues in cooperation with their human partners. Previous studies have demonstrated that people follow human and robot gaze, and that it can help them to cope with spatially ambiguous language. Our goal is to extend these findings into the domain of action, to determine how human and robot gaze can influence the speed and accuracy of human action. We report on results from a human–human cooperation experiment demonstrating that an agent’s vision of her/his partner’s gaze can significantly improve that agent’s performance in a cooperative task. We then implement a heuristic capability to generate such gaze cues by a humanoid robot that engages in the same cooperative interaction. The subsequent human–robot experiments demonstrate that a human agent can indeed exploit the predictive gaze of their robot partner in a cooperative task. This allows us to render the humanoid robot more human-like in its ability to communicate with humans. The long term objectives of the work are thus to identify social cooperation cues, and to validate their pertinence through implementation in a cooperative robot. The current research provides the robot with the capability to produce appropriate speech and gaze cues in the context of human–robot cooperation tasks. Gaze is manipulated in three conditions: Full gaze (coordinated eye and head), eyes hidden with sunglasses, and head fixed. We demonstrate the pertinence of these cues in terms of statistical measures of action times for humans in the context of a cooperative task, as gaze significantly facilitates cooperation as measured by human response times. PMID:22563315

  14. Recognition of Emotion from Facial Expressions with Direct or Averted Eye Gaze and Varying Expression Intensities in Children with Autism Disorder and Typically Developing Children

    Directory of Open Access Journals (Sweden)

    Dina Tell

    2014-01-01

    Full Text Available Eye gaze direction and expression intensity effects on emotion recognition in children with autism disorder and typically developing children were investigated. Children with autism disorder and typically developing children identified happy and angry expressions equally well. Children with autism disorder, however, were less accurate in identifying fear expressions across intensities and eye gaze directions. Children with autism disorder rated expressions with direct eyes, and 50% expressions, as more intense than typically developing children. A trend was also found for sad expressions, as children with autism disorder were less accurate in recognizing sadness at 100% intensity with direct eyes than typically developing children. Although the present research showed that children with autism disorder are sensitive to eye gaze direction, impairments in the recognition of fear, and possibly sadness, exist. Furthermore, children with autism disorder and typically developing children perceive the intensity of emotional expressions differently.

  15. Cross-coupling between accommodation and convergence is optimized for a broad range of directions and distances of gaze.

    Science.gov (United States)

    Nguyen, Dorothy; Vedamurthy, Indu; Schor, Clifton

    2008-03-01

    Accommodation and convergence systems are cross-coupled so that stimulation of one system produces responses by both systems. Ideally, the cross-coupled responses of accommodation and convergence match their respective stimuli. When expressed in diopters and meter angles, respectively, stimuli for accommodation and convergence are equal in the mid-sagittal plane when viewed with symmetrical convergence, where historically, the gains of the cross coupling (AC/A and CA/C ratios) have been quantified. However, targets at non-zero azimuth angles, when viewed with asymmetric convergence, present unequal stimuli for accommodation and convergence. Are the cross-links between the two systems calibrated to compensate for stimulus mismatches that increase with gaze-azimuth? We measured the response AC/A and stimulus CA/C ratios at zero azimuth, 17.5 and 30 deg of rightward gaze eccentricities with a Badal Optometer and Wheatstone-mirror haploscope. AC/A ratios were measured under open-loop convergence conditions along the iso-accommodation circle (locus of points that stimulate approximately equal amounts of accommodation to the two eyes at all azimuth angles). CA/C ratios were measured under open-loop accommodation conditions along the iso-vergence circle (locus of points that stimulate constant convergence at all azimuth angles). Our results show that the gain of accommodative-convergence (AC/A ratio) decreased and the bias of convergence-accommodation increased at the 30 deg gaze eccentricity. These changes are in directions that compensate for stimulus mismatches caused by spatial-viewing geometry during asymmetric convergence.

  16. Gaze shifts and fixations dominate gaze behavior of walking cats

    Science.gov (United States)

    Rivers, Trevor J.; Sirota, Mikhail G.; Guttentag, Andrew I.; Ogorodnikov, Dmitri A.; Shah, Neet A.; Beloozerova, Irina N.

    2014-01-01

    Vision is important for locomotion in complex environments. How it is used to guide stepping is not well understood. We used an eye search coil technique combined with an active marker-based head recording system to characterize the gaze patterns of cats walking over terrains of different complexity: (1) on a flat surface in the dark when no visual information was available, (2) on the flat surface in light when visual information was available but not required, (3) along the highly structured but regular and familiar surface of a horizontal ladder, a task for which visual guidance of stepping was required, and (4) along a pathway cluttered with many small stones, an irregularly structured surface that was new each day. Three cats walked in a 2.5 m corridor, and 958 passages were analyzed. Gaze activity during the time when the gaze was directed at the walking surface was subdivided into four behaviors based on speed of gaze movement along the surface: gaze shift (fast movement), gaze fixation (no movement), constant gaze (movement at the body’s speed), and slow gaze (the remainder). We found that gaze shifts and fixations dominated the cats’ gaze behavior during all locomotor tasks, jointly occupying 62–84% of the time when the gaze was directed at the surface. As visual complexity of the surface and demand on visual guidance of stepping increased, cats spent more time looking at the surface, looked closer to them, and switched between gaze behaviors more often. During both visually guided locomotor tasks, gaze behaviors predominantly followed a repeated cycle of forward gaze shift followed by fixation. We call this behavior “gaze stepping”. Each gaze shift took gaze to a site approximately 75–80 cm in front of the cat, which the cat reached in 0.7–1.2 s and 1.1–1.6 strides. Constant gaze occupied only 5–21% of the time cats spent looking at the walking surface. PMID:24973656

  17. Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability.

    Science.gov (United States)

    Willemse, Cesco; Marchesi, Serena; Wykowska, Agnieszka

    2018-01-01

    Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive-affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub) avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot's characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition) and in the other condition it looked at the opposite object 80% of the time (disjoint condition). Based on the literature in human-human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants' gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings.

  18. Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability

    Science.gov (United States)

    Willemse, Cesco; Marchesi, Serena; Wykowska, Agnieszka

    2018-01-01

    Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive–affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub) avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot’s characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition) and in the other condition it looked at the opposite object 80% of the time (disjoint condition). Based on the literature in human–human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants’ gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings. PMID:29459842

  19. Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability

    Directory of Open Access Journals (Sweden)

    Cesco Willemse

    2018-02-01

    Full Text Available Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive–affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot’s characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition and in the other condition it looked at the opposite object 80% of the time (disjoint condition. Based on the literature in human–human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants’ gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings.

  20. Judgments at Gaze Value: Gaze Cuing in Banner Advertisements, Its Effect on Attention Allocation and Product Judgments

    Directory of Open Access Journals (Sweden)

    Johanna Palcu

    2017-06-01

    Full Text Available Banner advertising is a popular means of promoting products and brands online. Although banner advertisements are often designed to be particularly attention grabbing, they frequently go unnoticed. Applying an eye-tracking procedure, the present research aimed to (a determine whether presenting human faces (static or animated in banner advertisements is an adequate tool for capturing consumers’ attention and thus overcoming the frequently observed phenomenon of banner blindness, (b to examine whether the gaze of a featured face possesses the ability to direct consumers’ attention toward specific elements (i.e., the product in an advertisement, and (c to establish whether the gaze direction of an advertised face influences consumers subsequent evaluation of the advertised product. We recorded participants’ eye gaze while they viewed a fictional online shopping page displaying banner advertisements that featured either no human face or a human face that was either static or animated and involved different gaze directions (toward or away from the advertised product. Moreover, we asked participants to subsequently evaluate a set of products, one of which was the product previously featured in the banner advertisement. Results showed that, when advertisements included a human face, participants’ attention was more attracted by and they looked longer at animated compared with static banner advertisements. Moreover, when a face gazed toward the product region, participants’ likelihood of looking at the advertised product increased regardless of whether the face was animated or not. Most important, gaze direction influenced subsequent product evaluations; that is, consumers indicated a higher intention to buy a product when it was previously presented in a banner advertisement that featured a face that gazed toward the product. The results suggest that while animation in banner advertising constitutes a salient feature that captures consumers

  1. Judgments at Gaze Value: Gaze Cuing in Banner Advertisements, Its Effect on Attention Allocation and Product Judgments.

    Science.gov (United States)

    Palcu, Johanna; Sudkamp, Jennifer; Florack, Arnd

    2017-01-01

    Banner advertising is a popular means of promoting products and brands online. Although banner advertisements are often designed to be particularly attention grabbing, they frequently go unnoticed. Applying an eye-tracking procedure, the present research aimed to (a) determine whether presenting human faces (static or animated) in banner advertisements is an adequate tool for capturing consumers' attention and thus overcoming the frequently observed phenomenon of banner blindness, (b) to examine whether the gaze of a featured face possesses the ability to direct consumers' attention toward specific elements (i.e., the product) in an advertisement, and (c) to establish whether the gaze direction of an advertised face influences consumers subsequent evaluation of the advertised product. We recorded participants' eye gaze while they viewed a fictional online shopping page displaying banner advertisements that featured either no human face or a human face that was either static or animated and involved different gaze directions (toward or away from the advertised product). Moreover, we asked participants to subsequently evaluate a set of products, one of which was the product previously featured in the banner advertisement. Results showed that, when advertisements included a human face, participants' attention was more attracted by and they looked longer at animated compared with static banner advertisements. Moreover, when a face gazed toward the product region, participants' likelihood of looking at the advertised product increased regardless of whether the face was animated or not. Most important, gaze direction influenced subsequent product evaluations; that is, consumers indicated a higher intention to buy a product when it was previously presented in a banner advertisement that featured a face that gazed toward the product. The results suggest that while animation in banner advertising constitutes a salient feature that captures consumers' visual attention, gaze

  2. Effects of Lighting Direction on the Impression of Faces and Objects and the Role of Gaze Direction in the Impression-Forming

    Directory of Open Access Journals (Sweden)

    Keiichi Horibata

    2011-10-01

    Full Text Available We examined whether lighting direction, left or right, has an influence on the impression of faces and objects, and the role of gaze direction in the impression-forming. In the first experiment, we examined how lighting directions influenced the impression of faces and objects. On each trial, a pair of faces or objects was presented on top of each other. Left side was brighter in one and right side was brighter in the other. The participants were asked to answer which face or object was more preferable. The results showed that the participants preferred left-brighter faces and objects significantly more frequently than right-brighter stimuli (p < .05, chi-square test. The effect was especially strong in the upright faces. The results suggested that faces and objects give better impressions when they are lit from the left. In the second experiment, we examined whether eye-movement would play a role in our preference for left-brighter faces and objects. We recorded eye-movements of the participants while doing the same task as the first experiment. The results showed that the participants' preference for left-brighter faces were stronger when the participant started viewing from the left. The gaze direction may modulate our impression-formation (Shimojo et al. 2003.

  3. Actively learning human gaze shifting paths for semantics-aware photo cropping.

    Science.gov (United States)

    Zhang, Luming; Gao, Yue; Ji, Rongrong; Xia, Yingjie; Dai, Qionghai; Li, Xuelong

    2014-05-01

    Photo cropping is a widely used tool in printing industry, photography, and cinematography. Conventional cropping models suffer from the following three challenges. First, the deemphasized role of semantic contents that are many times more important than low-level features in photo aesthetics. Second, the absence of a sequential ordering in the existing models. In contrast, humans look at semantically important regions sequentially when viewing a photo. Third, the difficulty of leveraging inputs from multiple users. Experience from multiple users is particularly critical in cropping as photo assessment is quite a subjective task. To address these challenges, this paper proposes semantics-aware photo cropping, which crops a photo by simulating the process of humans sequentially perceiving semantically important regions of a photo. We first project the local features (graphlets in this paper) onto the semantic space, which is constructed based on the category information of the training photos. An efficient learning algorithm is then derived to sequentially select semantically representative graphlets of a photo, and the selecting process can be interpreted by a path, which simulates humans actively perceiving semantics in a photo. Furthermore, we learn a prior distribution of such active graphlet paths from training photos that are marked as aesthetically pleasing by multiple users. The learned priors enforce the corresponding active graphlet path of a test photo to be maximally similar to those from the training photos. Experimental results show that: 1) the active graphlet path accurately predicts human gaze shifting, and thus is more indicative for photo aesthetics than conventional saliency maps and 2) the cropped photos produced by our approach outperform its competitors in both qualitative and quantitative comparisons.

  4. Gaze as a biometric

    Science.gov (United States)

    Yoon, Hong-Jun; Carmichael, Tandy R.; Tourassi, Georgia

    2014-03-01

    Two people may analyze a visual scene in two completely different ways. Our study sought to determine whether human gaze may be used to establish the identity of an individual. To accomplish this objective we investigated the gaze pattern of twelve individuals viewing still images with different spatial relationships. Specifically, we created 5 visual "dotpattern" tests to be shown on a standard computer monitor. These tests challenged the viewer's capacity to distinguish proximity, alignment, and perceptual organization. Each test included 50 images of varying difficulty (total of 250 images). Eye-tracking data were collected from each individual while taking the tests. The eye-tracking data were converted into gaze velocities and analyzed with Hidden Markov Models to develop personalized gaze profiles. Using leave-one-out cross-validation, we observed that these personalized profiles could differentiate among the 12 users with classification accuracy ranging between 53% and 76%, depending on the test. This was statistically significantly better than random guessing (i.e., 8.3% or 1 out of 12). Classification accuracy was higher for the tests where the users' average gaze velocity per case was lower. The study findings support the feasibility of using gaze as a biometric or personalized biomarker. These findings could have implications in Radiology training and the development of personalized e-learning environments.

  5. Gaze as a biometric

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hong-Jun [ORNL; Carmichael, Tandy [Tennessee Technological University; Tourassi, Georgia [ORNL

    2014-01-01

    Two people may analyze a visual scene in two completely different ways. Our study sought to determine whether human gaze may be used to establish the identity of an individual. To accomplish this objective we investigated the gaze pattern of twelve individuals viewing different still images with different spatial relationships. Specifically, we created 5 visual dot-pattern tests to be shown on a standard computer monitor. These tests challenged the viewer s capacity to distinguish proximity, alignment, and perceptual organization. Each test included 50 images of varying difficulty (total of 250 images). Eye-tracking data were collected from each individual while taking the tests. The eye-tracking data were converted into gaze velocities and analyzed with Hidden Markov Models to develop personalized gaze profiles. Using leave-one-out cross-validation, we observed that these personalized profiles could differentiate among the 12 users with classification accuracy ranging between 53% and 76%, depending on the test. This was statistically significantly better than random guessing (i.e., 8.3% or 1 out of 12). Classification accuracy was higher for the tests where the users average gaze velocity per case was lower. The study findings support the feasibility of using gaze as a biometric or personalized biomarker. These findings could have implications in Radiology training and the development of personalized e-learning environments.

  6. The Eye Gaze Direction of an Observed Person Can Bias Perception, Memory, and Attention in Adolescents with and without Autism Spectrum Disorder

    Science.gov (United States)

    Freeth, M.; Ropar, D.; Chapman, P.; Mitchell, P.

    2010-01-01

    The reported experiments aimed to investigate whether a person and his or her gaze direction presented in the context of a naturalistic scene cause perception, memory, and attention to be biased in typically developing adolescents and high-functioning adolescents with autism spectrum disorder (ASD). A novel computerized image manipulation program…

  7. Sexual dimorphism of male face shape, partnership status and the temporal context of relationship sought modulate women's preferences for direct gaze.

    Science.gov (United States)

    Conway, Claire A; Jones, Benedict C; DeBruine, Lisa M; Little, Anthony C

    2010-02-01

    Most previous studies of face preferences have investigated the physical cues that influence face preferences. Far fewer studies have investigated the effects of cues to the direction of others' social interest (i.e. gaze direction) on face preferences. Here we found that unpartnered women demonstrated stronger preferences for direct gaze (indicating social interest) from feminine male faces than from masculine male faces when judging men's attractiveness for long-term relationships, but not when judging men's attractiveness for short-term relationships. Moreover, unpartnered women's preferences for direct gaze from feminine men were stronger for long-term than short-term relationships, but there was no comparable effect for judgements of masculine men. No such effects were evident among women with romantic partners, potentially reflecting different motivations underlying partnered and unpartnered women's judgements of men's attractiveness. Collectively these findings (1) complement previous findings whereby women demonstrated stronger preferences for feminine men as long-term than short-term partners, (2) demonstrate context-sensitivity in the integration of physical and social cues in face preferences, and (3) suggest that gaze preferences may function, at least in part, to facilitate efficient allocation of mating effort.

  8. The effect of gaze angle on the evaluations of SAR and temperature rise in human eye under plane-wave exposures from 0.9 to 10 GHz

    International Nuclear Information System (INIS)

    Diao, Yinliang; Leung, Sai-Wing; Sun, Weinong; Siu, Yun-Ming; Kong, Richard; Hung Chan, Kwok

    2016-01-01

    This article investigates the effect of gaze angle on the specific absorption rate (SAR) and temperature rise in human eye under electromagnetic exposures from 0.9 to 10 GHz. Eye models in different gaze angles are developed based on bio-metric data. The spatial-average SARs in eyes are investigated using the finite-difference time-domain method, and the corresponding maximum temperature rises in lens are calculated by the finite-difference method. It is found that the changes in the gaze angle produce a maximum variation of 35, 12 and 20 % in the eye-averaged SAR, peak 10 g average SAR and temperature rise, respectively. Results also reveal that the eye-averaged SAR is more sensitive to the changes in the gaze angle than peak 10 g average SAR, especially at higher frequencies. (authors)

  9. Face and gaze perception in borderline personality disorder: An electrical neuroimaging study.

    Science.gov (United States)

    Berchio, Cristina; Piguet, Camille; Gentsch, Kornelia; Küng, Anne-Lise; Rihs, Tonia A; Hasler, Roland; Aubry, Jean-Michel; Dayer, Alexandre; Michel, Christoph M; Perroud, Nader

    2017-11-30

    Humans are sensitive to gaze direction from early life, and gaze has social and affective values. Borderline personality disorder (BPD) is a clinical condition characterized by emotional dysregulation and enhanced sensitivity to affective and social cues. In this study we wanted to investigate the temporal-spatial dynamics of spontaneous gaze processing in BPD. We used a 2-back-working-memory task, in which neutral faces with direct and averted gaze were presented. Gaze was used as an emotional modulator of event-related-potentials to faces. High density EEG data were acquired in 19 females with BPD and 19 healthy women, and analyzed with a spatio-temporal microstates analysis approach. Independently of gaze direction, BPD patients showed altered N170 and P200 topographies for neutral faces. Source localization revealed that the anterior cingulate and other prefrontal regions were abnormally activated during the N170 component related to face encoding, while middle temporal deactivations were observed during the P200 component. Post-task affective ratings showed that BPD patients had difficulty to disambiguate neutral gaze. This study provides first evidence for an early neural bias toward neutral faces in BPD independent of gaze direction and also suggests the importance of considering basic aspects of social cognition in identifying biological risk factors of BPD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Latvijas gaze

    International Nuclear Information System (INIS)

    1994-04-01

    A collection of photocopies of materials (such as overheads etc.) used at a seminar (organized by the Board of Directors of the company designated ''Latvijas Gaze'' in connection with The National Oil and Gas Company of Denmark, DONG) comprising an analysis of training needs with regard to marketing of gas technology and consultancy to countries in Europe, especially with regard to Latvia. (AB)

  11. Obama cares about visuo-spatial attention: perception of political figures moves attention and determines gaze direction.

    Science.gov (United States)

    Mills, Mark; Smith, Kevin B; Hibbing, John R; Dodd, Michael D

    2015-02-01

    Processing an abstract concept such as political ideology by itself is difficult but becomes easier when a background situation contextualizes it. Political ideology within American politics, for example, is commonly processed using space metaphorically, i.e., the political "left" and "right" (referring to Democrat and Republican views, respectively), presumably to provide a common metric to which abstract features of ideology can be grounded and understood. Commonplace use of space as metaphor raises the question of whether an inherently non-spatial stimulus (e.g., picture of the political "left" leader, Barack Obama) can trigger a spatially-specific response (e.g., attentional bias toward "left" regions of the visual field). Accordingly, pictures of well-known Democrats and Republicans were presented as central cues in peripheral target detection (Experiment 1) and saccadic free-choice (Experiment 2) tasks to determine whether perception of stimuli lacking a direct association with physical space nonetheless induce attentional and oculomotor biases in the direction compatible with the ideological category of the cue (i.e., Democrat/left and Republican/right). In Experiment 1, target detection following presentation of a Democrat (Republican) was facilitated for targets appearing to the left (right). In Experiment 2, participants were more likely to look left (right) following presentation of a Democrat (Republican). Thus, activating an internal representation of political ideology induced a shift of attention and biased choice of gaze direction in a spatially-specific manner. These findings demonstrate that the link between conceptual processing and spatial attention can be totally arbitrary, with no reference to physical or symbolic spatial information. Published by Elsevier B.V.

  12. Dysfunctional gaze processing in bipolar disorder

    Directory of Open Access Journals (Sweden)

    Cristina Berchio

    2017-01-01

    The present study provides neurophysiological evidence for abnormal gaze processing in BP and suggests dysfunctional processing of direct eye contact as a prominent characteristic of bipolar disorder.

  13. The Potential of the Bi-Directional Gaze: A Call for Neuroscientific Research on the Simultaneous Activation of the Sympathetic and Parasympathetic Nervous Systems through Tantric Practice

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Lidke

    2016-11-01

    Full Text Available This paper is a call for the development of a neuroscientific research protocol for the study of the impact of Tantric practice on the autonomic nervous system. Tantric texts like Abhinavagupta’s Tantrāloka map out a complex meditative ritual system in which inward-gazing, apophatic, sense-denying contemplative practices are combined with outward-gazing, kataphatic sense-activating ritual practices. Abhinavagupta announces a culminating “bi-directional” state (pratimīlana-samādhi as the highest natural state (sahaja-samādhi in which the practitioner becomes a perfected yogi (siddhayogi. This state of maximized cognitive capacities, in which one’s inward gaze and outward world-engagement are held in balance, appears to be one in which the anabolic metabolic processes of the parasympathetic nervous system and the catabolic metabolic processes of the sympathetic nervous systems are simultaneously activated and integrated. Akin to secularized mindfulness and compassion training protocols like Emory’s CBCT, I propose the development of secularized “Tantric protocols” for the development of secular and tradition-specific methods for further exploring the potential of the human neurological system.

  14. Between Gazes

    DEFF Research Database (Denmark)

    Elias, Camelia

    2009-01-01

    In the film documentary Zizek! (2006) Astra Taylor, the film’s director, introduces Slavoj Zizek and his central notions of Lacanian psychoanalysis as they tie in with Marxism, ideology, and culture. Apart from following Zizek from New York to his home in Ljubljana, the documentary presents...... delivers his thoughts on philosophy while in bed or in the bathroom. It is clear that one of the devices that the documentary uses in its portrayal of Zizek is the palimpsest, and what is being layered is the gaze. My essay introduces the idea of layering as a case of intermediality between different art...

  15. Facilitated orienting underlies fearful face-enhanced gaze cueing of spatial location

    Directory of Open Access Journals (Sweden)

    Joshua M. Carlson

    2016-12-01

    Full Text Available Faces provide a platform for non-verbal communication through emotional expression and eye gaze. Fearful facial expressions are salient indicators of potential threat within the environment, which automatically capture observers’ attention. However, the degree to which fearful facial expressions facilitate attention to others’ gaze is unresolved. Given that fearful gaze indicates the location of potential threat, it was hypothesized that fearful gaze facilitates location processing. To test this hypothesis, a gaze cueing study with fearful and neutral faces assessing target localization was conducted. The task consisted of leftward, rightward, and forward/straight gaze trials. The inclusion of forward gaze trials allowed for the isolation of orienting and disengagement components of gaze-directed attention. The results suggest that both neutral and fearful gaze modulates attention through orienting and disengagement components. Fearful gaze, however, resulted in quicker orienting than neutral gaze. Thus, fearful faces enhance gaze cueing of spatial location through facilitated orienting.

  16. Effectiveness of the Gaze Direction Recognition Task for Chronic Neck Pain and Cervical Range of Motion: A Randomized Controlled Pilot Study

    Directory of Open Access Journals (Sweden)

    Satoshi Nobusako

    2012-01-01

    Full Text Available We developed a mental task with gaze direction recognition (GDR by which subjects observed neck rotation of another individual from behind and attempted to recognize the direction of gaze. A randomized controlled trial was performed in test (=9 and control (=8 groups of subjects with chronic neck pain undergoing physical therapy either with or without the GDR task carried out over 12 sessions during a three-week period. Primary outcome measures were defined as the active range of motion and pain on rotation of the neck. Secondary outcome measures were reaction time (RT and response accuracy in the GDR task group. ANOVA indicated a main effect for task session and group, and interaction of session. Post hoc testing showed that the GDR task group exhibited a significant simple main effect upon session, and significant sequential improvement of neck motion and relief of neck pain. Rapid effectiveness was significant in both groups. The GDR task group had a significant session-to-session reduction of RTs in correct responses. In conclusion, the GDR task we developed provides a promising rehabilitation measure for chronic neck pain.

  17. Eye gaze tracking based on the shape of pupil image

    Science.gov (United States)

    Wang, Rui; Qiu, Jian; Luo, Kaiqing; Peng, Li; Han, Peng

    2018-01-01

    Eye tracker is an important instrument for research in psychology, widely used in attention, visual perception, reading and other fields of research. Because of its potential function in human-computer interaction, the eye gaze tracking has already been a topic of research in many fields over the last decades. Nowadays, with the development of technology, non-intrusive methods are more and more welcomed. In this paper, we will present a method based on the shape of pupil image to estimate the gaze point of human eyes without any other intrusive devices such as a hat, a pair of glasses and so on. After using the ellipse fitting algorithm to deal with the pupil image we get, we can determine the direction of the fixation by the shape of the pupil.The innovative aspect of this method is to utilize the new idea of the shape of the pupil so that we can avoid much complicated algorithm. The performance proposed is very helpful for the study of eye gaze tracking, which just needs one camera without infrared light to know the changes in the shape of the pupil to determine the direction of the eye gazing, no additional condition is required.

  18. A neural-based remote eye gaze tracker under natural head motion.

    Science.gov (United States)

    Torricelli, Diego; Conforto, Silvia; Schmid, Maurizio; D'Alessio, Tommaso

    2008-10-01

    A novel approach to view-based eye gaze tracking for human computer interface (HCI) is presented. The proposed method combines different techniques to address the problems of head motion, illumination and usability in the framework of low cost applications. Feature detection and tracking algorithms have been designed to obtain an automatic setup and strengthen the robustness to light conditions. An extensive analysis of neural solutions has been performed to deal with the non-linearity associated with gaze mapping under free-head conditions. No specific hardware, such as infrared illumination or high-resolution cameras, is needed, rather a simple commercial webcam working in visible light spectrum suffices. The system is able to classify the gaze direction of the user over a 15-zone graphical interface, with a success rate of 95% and a global accuracy of around 2 degrees , comparable with the vast majority of existing remote gaze trackers.

  19. Differences in gaze anticipation for locomotion with and without vision

    Science.gov (United States)

    Authié, Colas N.; Hilt, Pauline M.; N'Guyen, Steve; Berthoz, Alain; Bennequin, Daniel

    2015-01-01

    Previous experimental studies have shown a spontaneous anticipation of locomotor trajectory by the head and gaze direction during human locomotion. This anticipatory behavior could serve several functions: an optimal selection of visual information, for instance through landmarks and optic flow, as well as trajectory planning and motor control. This would imply that anticipation remains in darkness but with different characteristics. We asked 10 participants to walk along two predefined complex trajectories (limaçon and figure eight) without any cue on the trajectory to follow. Two visual conditions were used: (i) in light and (ii) in complete darkness with eyes open. The whole body kinematics were recorded by motion capture, along with the participant's right eye movements. We showed that in darkness and in light, horizontal gaze anticipates the orientation of the head which itself anticipates the trajectory direction. However, the horizontal angular anticipation decreases by a half in darkness for both gaze and head. In both visual conditions we observed an eye nystagmus with similar properties (frequency and amplitude). The main difference comes from the fact that in light, there is a shift of the orientations of the eye nystagmus and the head in the direction of the trajectory. These results suggest that a fundamental function of gaze is to represent self motion, stabilize the perception of space during locomotion, and to simulate the future trajectory, regardless of the vision condition. PMID:26106313

  20. Conjugate Gaze Palsies

    Science.gov (United States)

    ... version Home Brain, Spinal Cord, and Nerve Disorders Cranial Nerve Disorders Conjugate Gaze Palsies Horizontal gaze palsy Vertical ... Version. DOCTORS: Click here for the Professional Version Cranial Nerve Disorders Overview of the Cranial Nerves Internuclear Ophthalmoplegia ...

  1. Gaze beats mouse

    DEFF Research Database (Denmark)

    Mateo, Julio C.; San Agustin, Javier; Hansen, John Paulin

    2008-01-01

    Facial EMG for selection is fast, easy and, combined with gaze pointing, it can provide completely hands-free interaction. In this pilot study, 5 participants performed a simple point-and-select task using mouse or gaze for pointing and a mouse button or a facial-EMG switch for selection. Gaze...

  2. Single gaze gestures

    DEFF Research Database (Denmark)

    Møllenbach, Emilie; Lilholm, Martin; Gail, Alastair

    2010-01-01

    This paper examines gaze gestures and their applicability as a generic selection method for gaze-only controlled interfaces. The method explored here is the Single Gaze Gesture (SGG), i.e. gestures consisting of a single point-to-point eye movement. Horizontal and vertical, long and short SGGs were...

  3. Holistic integration of gaze cues in visual face and body perception: Evidence from the composite design.

    Science.gov (United States)

    Vrancken, Leia; Germeys, Filip; Verfaillie, Karl

    2017-01-01

    A considerable amount of research on identity recognition and emotion identification with the composite design points to the holistic processing of these aspects in faces and bodies. In this paradigm, the interference from a nonattended face half on the perception of the attended half is taken as evidence for holistic processing (i.e., a composite effect). Far less research, however, has been dedicated to the concept of gaze. Nonetheless, gaze perception is a substantial component of face and body perception, and holds critical information for everyday communicative interactions. Furthermore, the ability of human observers to detect direct versus averted eye gaze is effortless, perhaps similar to identity perception and emotion recognition. However, the hypothesis of holistic perception of eye gaze has never been tested directly. Research on gaze perception with the composite design could facilitate further systematic comparison with other aspects of face and body perception that have been investigated using the composite design (i.e., identity and emotion). In the present research, a composite design was administered to assess holistic processing of gaze cues in faces (Experiment 1) and bodies (Experiment 2). Results confirmed that eye and head orientation (Experiment 1A) and head and body orientation (Experiment 2A) are integrated in a holistic manner. However, the composite effect was not completely disrupted by inversion (Experiments 1B and 2B), a finding that will be discussed together with implications for future research.

  4. Human place and response learning: navigation strategy selection, pupil size and gaze behavior.

    Science.gov (United States)

    de Condappa, Olivier; Wiener, Jan M

    2016-01-01

    In this study, we examined the cognitive processes and ocular behavior associated with on-going navigation strategy choice using a route learning paradigm that distinguishes between three different wayfinding strategies: an allocentric place strategy, and the egocentric associative cue and beacon response strategies. Participants approached intersections of a known route from a variety of directions, and were asked to indicate the direction in which the original route continued. Their responses in a subset of these test trials allowed the assessment of strategy choice over the course of six experimental blocks. The behavioral data revealed an initial maladaptive bias for a beacon response strategy, with shifts in favor of the optimal configuration place strategy occurring over the course of the experiment. Response time analysis suggests that the configuration strategy relied on spatial transformations applied to a viewpoint-dependent spatial representation, rather than direct access to an allocentric representation. Furthermore, pupillary measures reflected the employment of place and response strategies throughout the experiment, with increasing use of the more cognitively demanding configuration strategy associated with increases in pupil dilation. During test trials in which known intersections were approached from different directions, visual attention was directed to the landmark encoded during learning as well as the intended movement direction. Interestingly, the encoded landmark did not differ between the three navigation strategies, which is discussed in the context of initial strategy choice and the parallel acquisition of place and response knowledge.

  5. Emotion Unchained: Facial Expression Modulates Gaze Cueing under Cognitive Load.

    Science.gov (United States)

    Pecchinenda, Anna; Petrucci, Manuel

    2016-01-01

    Direction of eye gaze cues spatial attention, and typically this cueing effect is not modulated by the expression of a face unless top-down processes are explicitly or implicitly involved. To investigate the role of cognitive control on gaze cueing by emotional faces, participants performed a gaze cueing task with happy, angry, or neutral faces under high (i.e., counting backward by 7) or low cognitive load (i.e., counting forward by 2). Results show that high cognitive load enhances gaze cueing effects for angry facial expressions. In addition, cognitive load reduces gaze cueing for neutral faces, whereas happy facial expressions and gaze affected object preferences regardless of load. This evidence clearly indicates a differential role of cognitive control in processing gaze direction and facial expression, suggesting that under typical conditions, when we shift attention based on social cues from another person, cognitive control processes are used to reduce interference from emotional information.

  6. Eye gaze in intelligent user interfaces gaze-based analyses, models and applications

    CERN Document Server

    Nakano, Yukiko I; Bader, Thomas

    2013-01-01

    Remarkable progress in eye-tracking technologies opened the way to design novel attention-based intelligent user interfaces, and highlighted the importance of better understanding of eye-gaze in human-computer interaction and human-human communication. For instance, a user's focus of attention is useful in interpreting the user's intentions, their understanding of the conversation, and their attitude towards the conversation. In human face-to-face communication, eye gaze plays an important role in floor management, grounding, and engagement in conversation.Eye Gaze in Intelligent User Interfac

  7. Speaker gaze increases information coupling between infant and adult brains.

    Science.gov (United States)

    Leong, Victoria; Byrne, Elizabeth; Clackson, Kaili; Georgieva, Stanimira; Lam, Sarah; Wass, Sam

    2017-12-12

    When infants and adults communicate, they exchange social signals of availability and communicative intention such as eye gaze. Previous research indicates that when communication is successful, close temporal dependencies arise between adult speakers' and listeners' neural activity. However, it is not known whether similar neural contingencies exist within adult-infant dyads. Here, we used dual-electroencephalography to assess whether direct gaze increases neural coupling between adults and infants during screen-based and live interactions. In experiment 1 ( n = 17), infants viewed videos of an adult who was singing nursery rhymes with ( i ) direct gaze (looking forward), ( ii ) indirect gaze (head and eyes averted by 20°), or ( iii ) direct-oblique gaze (head averted but eyes orientated forward). In experiment 2 ( n = 19), infants viewed the same adult in a live context, singing with direct or indirect gaze. Gaze-related changes in adult-infant neural network connectivity were measured using partial directed coherence. Across both experiments, the adult had a significant (Granger) causal influence on infants' neural activity, which was stronger during direct and direct-oblique gaze relative to indirect gaze. During live interactions, infants also influenced the adult more during direct than indirect gaze. Further, infants vocalized more frequently during live direct gaze, and individual infants who vocalized longer also elicited stronger synchronization from the adult. These results demonstrate that direct gaze strengthens bidirectional adult-infant neural connectivity during communication. Thus, ostensive social signals could act to bring brains into mutual temporal alignment, creating a joint-networked state that is structured to facilitate information transfer during early communication and learning. Copyright © 2017 the Author(s). Published by PNAS.

  8. Gaze Tracking Through Smartphones

    DEFF Research Database (Denmark)

    Skovsgaard, Henrik; Hansen, John Paulin; Møllenbach, Emilie

    Mobile gaze trackers embedded in smartphones or tablets provide a powerful personal link to game devices, head-mounted micro-displays, pc´s, and TV’s. This link may offer a main road to the mass market for gaze interaction, we suggest.......Mobile gaze trackers embedded in smartphones or tablets provide a powerful personal link to game devices, head-mounted micro-displays, pc´s, and TV’s. This link may offer a main road to the mass market for gaze interaction, we suggest....

  9. Attention to gaze and emotion in schizophrenia.

    Science.gov (United States)

    Schwartz, Barbara L; Vaidya, Chandan J; Howard, James H; Deutsch, Stephen I

    2010-11-01

    Individuals with schizophrenia have difficulty interpreting social and emotional cues such as facial expression, gaze direction, body position, and voice intonation. Nonverbal cues are powerful social signals but are often processed implicitly, outside the focus of attention. The aim of this research was to assess implicit processing of social cues in individuals with schizophrenia. Patients with schizophrenia or schizoaffective disorder and matched controls performed a primary task of word classification with social cues in the background. Participants were asked to classify target words (LEFT/RIGHT) by pressing a key that corresponded to the word, in the context of facial expressions with eye gaze averted to the left or right. Although facial expression and gaze direction were irrelevant to the task, these facial cues influenced word classification performance. Participants were slower to classify target words (e.g., LEFT) that were incongruent to gaze direction (e.g., eyes averted to the right) compared to target words (e.g., LEFT) that were congruent to gaze direction (e.g., eyes averted to the left), but this only occurred for expressions of fear. This pattern did not differ for patients and controls. The results showed that threat-related signals capture the attention of individuals with schizophrenia. These data suggest that implicit processing of eye gaze and fearful expressions is intact in schizophrenia. (c) 2010 APA, all rights reserved

  10. The visual development of hand-centered receptive fields in a neural network model of the primate visual system trained with experimentally recorded human gaze changes.

    Science.gov (United States)

    Galeazzi, Juan M; Navajas, Joaquín; Mender, Bedeho M W; Quian Quiroga, Rodrigo; Minini, Loredana; Stringer, Simon M

    2016-01-01

    Neurons have been found in the primate brain that respond to objects in specific locations in hand-centered coordinates. A key theoretical challenge is to explain how such hand-centered neuronal responses may develop through visual experience. In this paper we show how hand-centered visual receptive fields can develop using an artificial neural network model, VisNet, of the primate visual system when driven by gaze changes recorded from human test subjects as they completed a jigsaw. A camera mounted on the head captured images of the hand and jigsaw, while eye movements were recorded using an eye-tracking device. This combination of data allowed us to reconstruct the retinal images seen as humans undertook the jigsaw task. These retinal images were then fed into the neural network model during self-organization of its synaptic connectivity using a biologically plausible trace learning rule. A trace learning mechanism encourages neurons in the model to learn to respond to input images that tend to occur in close temporal proximity. In the data recorded from human subjects, we found that the participant's gaze often shifted through a sequence of locations around a fixed spatial configuration of the hand and one of the jigsaw pieces. In this case, trace learning should bind these retinal images together onto the same subset of output neurons. The simulation results consequently confirmed that some cells learned to respond selectively to the hand and a jigsaw piece in a fixed spatial configuration across different retinal views.

  11. Gaze interaction from bed

    DEFF Research Database (Denmark)

    Hansen, John Paulin; San Agustin, Javier; Jensen, Henrik Tomra Skovsgaard Hegner

    2011-01-01

    This paper presents a low-cost gaze tracking solution for bedbound people composed of free-ware tracking software and commodity hardware. Gaze interaction is done on a large wall-projected image, visible to all people present in the room. The hardware equipment leaves physical space free to assis...

  12. Gazing and Performing

    DEFF Research Database (Denmark)

    Larsen, Jonas; Urry, John

    2011-01-01

    The Tourist Gaze [Urry J, 1990 (Sage, London)] is one of the most discussed and cited tourism books (with about 4000 citations on Google scholar). Whilst wide ranging in scope, the book is known for the Foucault-inspired concept of the tourist gaze that brings out the fundamentally visual and image...

  13. Direct dating of human fossils.

    Science.gov (United States)

    Grün, Rainer

    2006-01-01

    The methods that can be used for the direct dating of human remains comprise of radiocarbon, U-series, electron spin resonance (ESR), and amino acid racemization (AAR). This review gives an introduction to these methods in the context of dating human bones and teeth. Recent advances in ultrafiltration techniques have expanded the dating range of radiocarbon. It now seems feasible to reliably date bones up to 55,000 years. New developments in laser ablation mass spectrometry permit the in situ analysis of U-series isotopes, thus providing a rapid and virtually non-destructive dating method back to about 300,000 years. This is of particular importance when used in conjunction with non-destructive ESR analysis. New approaches in AAR analysis may lead to a renaissance of this method. The potential and present limitations of these direct dating techniques are discussed for sites relevant to the reconstruction of modern human evolution, including Florisbad, Border Cave, Tabun, Skhul, Qafzeh, Vindija, Banyoles, and Lake Mungo. (c) 2006 Wiley-Liss, Inc.

  14. Look Together: Analyzing Gaze Coordination with Epistemic Network Analysis

    Directory of Open Access Journals (Sweden)

    Sean eAndrist

    2015-07-01

    Full Text Available When conversing and collaborating in everyday situations, people naturally and interactively align their behaviors with each other across various communication channels, including speech, gesture, posture, and gaze. Having access to a partner's referential gaze behavior has been shown to be particularly important in achieving collaborative outcomes, but the process in which people's gaze behaviors unfold over the course of an interaction and become tightly coordinated is not well understood. In this paper, we present work to develop a deeper and more nuanced understanding of coordinated referential gaze in collaborating dyads. We recruited 13 dyads to participate in a collaborative sandwich-making task and used dual mobile eye tracking to synchronously record each participant's gaze behavior. We used a relatively new analysis technique—epistemic network analysis—to jointly model the gaze behaviors of both conversational participants. In this analysis, network nodes represent gaze targets for each participant, and edge strengths convey the likelihood of simultaneous gaze to the connected target nodes during a given time-slice. We divided collaborative task sequences into discrete phases to examine how the networks of shared gaze evolved over longer time windows. We conducted three separate analyses of the data to reveal (1 properties and patterns of how gaze coordination unfolds throughout an interaction sequence, (2 optimal time lags of gaze alignment within a dyad at different phases of the interaction, and (3 differences in gaze coordination patterns for interaction sequences that lead to breakdowns and repairs. In addition to contributing to the growing body of knowledge on the coordination of gaze behaviors in joint activities, this work has implications for the design of future technologies that engage in situated interactions with human users.

  15. Toward Optimization of Gaze-Controlled Human-Computer Interaction: Application to Hindi Virtual Keyboard for Stroke Patients.

    Science.gov (United States)

    Meena, Yogesh Kumar; Cecotti, Hubert; Wong-Lin, Kongfatt; Dutta, Ashish; Prasad, Girijesh

    2018-04-01

    Virtual keyboard applications and alternative communication devices provide new means of communication to assist disabled people. To date, virtual keyboard optimization schemes based on script-specific information, along with multimodal input access facility, are limited. In this paper, we propose a novel method for optimizing the position of the displayed items for gaze-controlled tree-based menu selection systems by considering a combination of letter frequency and command selection time. The optimized graphical user interface layout has been designed for a Hindi language virtual keyboard based on a menu wherein 10 commands provide access to type 88 different characters, along with additional text editing commands. The system can be controlled in two different modes: eye-tracking alone and eye-tracking with an access soft-switch. Five different keyboard layouts have been presented and evaluated with ten healthy participants. Furthermore, the two best performing keyboard layouts have been evaluated with eye-tracking alone on ten stroke patients. The overall performance analysis demonstrated significantly superior typing performance, high usability (87% SUS score), and low workload (NASA TLX with 17 scores) for the letter frequency and time-based organization with script specific arrangement design. This paper represents the first optimized gaze-controlled Hindi virtual keyboard, which can be extended to other languages.

  16. Can gaze-contingent mirror-feedback from unfamiliar faces alter self-recognition?

    Science.gov (United States)

    Estudillo, Alejandro J; Bindemann, Markus

    2017-05-01

    This study focuses on learning of the self, by examining how human observers update internal representations of their own face. For this purpose, we present a novel gaze-contingent paradigm, in which an onscreen face mimics observers' own eye-gaze behaviour (in the congruent condition), moves its eyes in different directions to that of the observers (incongruent condition), or remains static and unresponsive (neutral condition). Across three experiments, the mimicry of the onscreen face did not affect observers' perceptual self-representations. However, this paradigm influenced observers' reports of their own face. This effect was such that observers felt the onscreen face to be their own and that, if the onscreen gaze had moved on its own accord, observers expected their own eyes to move too. The theoretical implications of these findings are discussed.

  17. Gliding and Saccadic Gaze Gesture Recognition in Real Time

    DEFF Research Database (Denmark)

    Rozado, David; San Agustin, Javier; Rodriguez, Francisco

    2012-01-01

    , and their corresponding real-time recognition algorithms, Hierarchical Temporal Memory networks and the Needleman-Wunsch algorithm for sequence alignment. Our results show how a specific combination of gaze gesture modality, namely saccadic gaze gestures, and recognition algorithm, Needleman-Wunsch, allows for reliable...... usage of intentional gaze gestures to interact with a computer with accuracy rates of up to 98% and acceptable completion speed. Furthermore, the gesture recognition engine does not interfere with otherwise standard human-machine gaze interaction generating therefore, very low false positive rates...

  18. Face Age and Eye Gaze Influence Older Adults' Emotion Recognition.

    Science.gov (United States)

    Campbell, Anna; Murray, Janice E; Atkinson, Lianne; Ruffman, Ted

    2017-07-01

    Eye gaze has been shown to influence emotion recognition. In addition, older adults (over 65 years) are not as influenced by gaze direction cues as young adults (18-30 years). Nevertheless, these differences might stem from the use of young to middle-aged faces in emotion recognition research because older adults have an attention bias toward old-age faces. Therefore, using older face stimuli might allow older adults to process gaze direction cues to influence emotion recognition. To investigate this idea, young and older adults completed an emotion recognition task with young and older face stimuli displaying direct and averted gaze, assessing labeling accuracy for angry, disgusted, fearful, happy, and sad faces. Direct gaze rather than averted gaze improved young adults' recognition of emotions in young and older faces, but for older adults this was true only for older faces. The current study highlights the impact of stimulus face age and gaze direction on emotion recognition in young and older adults. The use of young face stimuli with direct gaze in most research might contribute to age-related emotion recognition differences. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Comprehension and utilisation of pointing gestures and gazing in dog-human communication in relatively complex situations.

    Science.gov (United States)

    Lakatos, Gabriella; Gácsi, Márta; Topál, József; Miklósi, Adám

    2012-03-01

    The aim of the present investigation was to study the visual communication between humans and dogs in relatively complex situations. In the present research, we have modelled more lifelike situations in contrast to previous studies which often relied on using only two potential hiding locations and direct association between the communicative signal and the signalled object. In Study 1, we have provided the dogs with four potential hiding locations, two on each side of the experimenter to see whether dogs are able to choose the correct location based on the pointing gesture. In Study 2, dogs had to rely on a sequence of pointing gestures displayed by two different experimenters. We have investigated whether dogs are able to recognise an 'indirect signal', that is, a pointing toward a pointer. In Study 3, we have examined whether dogs can understand indirect information about a hidden object and direct the owner to the particular location. Study 1 has revealed that dogs are unlikely to rely on extrapolating precise linear vectors along the pointing arm when relying on human pointing gestures. Instead, they rely on a simple rule of following the side of the human gesturing. If there were more targets on the same side of the human, they showed a preference for the targets closer to the human. Study 2 has shown that dogs are able to rely on indirect pointing gestures but the individual performances suggest that this skill may be restricted to a certain level of complexity. In Study 3, we have found that dogs are able to localise the hidden object by utilising indirect human signals, and they are able to convey this information to their owner.

  20. Gaze Behavior, Believability, Likability and the iCat

    NARCIS (Netherlands)

    Poel, Mannes; Heylen, Dirk K.J.; Meulemans, M.; Nijholt, Antinus; Stock, O.; Nishida, T.

    2007-01-01

    The iCat is a user-interface robot with the ability to express a range of emotions through its facial features. This paper summarizes our research whether we can increase the believability and likability of the iCat for its human partners through the application of gaze behaviour. Gaze behaviour

  1. Gaze Behavior, Believability, Likability and the iCat

    NARCIS (Netherlands)

    Nijholt, Antinus; Poel, Mannes; Heylen, Dirk K.J.; Stock, O.; Nishida, T.; Meulemans, M.; van Bremen, A.

    2009-01-01

    The iCat is a user-interface robot with the ability to express a range of emotions through its facial features. This paper summarizes our research whether we can increase the believability and likability of the iCat for its human partners through the application of gaze behaviour. Gaze behaviour

  2. Preliminary study of gaze toward humans in photographs by individuals with autism, Down syndrome, or other intellectual disabilities: implications for design of visual scene displays.

    Science.gov (United States)

    Wilkinson, Krista M; Light, Janice

    2014-06-01

    Visual scene displays (VSDs) are a form of augmentative and alternative communication display in which language concepts are embedded into an image of a naturalistic event. VSDs are based on the theory that language learning occurs through interactions with other people, and recommendations for VSD design have emphasized using images of these events that include humans. However, many VSDs also include other items that could potentially be distracting. We examined gaze fixation in 18 school-aged participants with and without severe intellectual/developmental disabilities (i.e., individuals with typical development, autism, Down syndrome and other intellectual disabilities) while they viewed photographs with human figures of various sizes and locations in the image, appearing alongside other interesting, and potentially distracting items. In all groups, the human figures attracted attention rapidly (within 1.5 seconds). The proportions of each participant's own fixation time spent on the human figures were similar across all groups, as were the proportions of total fixations made to the human figures. Although the findings are preliminary, this initial evidence supports the inclusion of humans in VSD images.

  3. Infants' Developing Understanding of Social Gaze

    Science.gov (United States)

    Beier, Jonathan S.; Spelke, Elizabeth S.

    2012-01-01

    Young infants are sensitive to self-directed social actions, but do they appreciate the intentional, target-directed nature of such behaviors? The authors addressed this question by investigating infants' understanding of social gaze in third-party interactions (N = 104). Ten-month-old infants discriminated between 2 people in mutual versus…

  4. Utilizing Gaze Behavior for Inferring Task Transitions Using Abstract Hidden Markov Models

    Directory of Open Access Journals (Sweden)

    Daniel Fernando Tello Gamarra

    2016-12-01

    Full Text Available We demonstrate an improved method for utilizing observed gaze behavior and show that it is useful in inferring hand movement intent during goal directed tasks. The task dynamics and the relationship between hand and gaze behavior are learned using an Abstract Hidden Markov Model (AHMM. We show that the predicted hand movement transitions occur consistently earlier in AHMM models with gaze than those models that do not include gaze observations.

  5. Reading faces: differential lateral gaze bias in processing canine and human facial expressions in dogs and 4-year-old children.

    Directory of Open Access Journals (Sweden)

    Anaïs Racca

    Full Text Available Sensitivity to the emotions of others provides clear biological advantages. However, in the case of heterospecific relationships, such as that existing between dogs and humans, there are additional challenges since some elements of the expression of emotions are species-specific. Given that faces provide important visual cues for communicating emotional state in both humans and dogs, and that processing of emotions is subject to brain lateralisation, we investigated lateral gaze bias in adult dogs when presented with pictures of expressive human and dog faces. Our analysis revealed clear differences in laterality of eye movements in dogs towards conspecific faces according to the emotional valence of the expressions. Differences were also found towards human faces, but to a lesser extent. For comparative purpose, a similar experiment was also run with 4-year-old children and it was observed that they showed differential processing of facial expressions compared to dogs, suggesting a species-dependent engagement of the right or left hemisphere in processing emotions.

  6. Reading faces: differential lateral gaze bias in processing canine and human facial expressions in dogs and 4-year-old children.

    Science.gov (United States)

    Racca, Anaïs; Guo, Kun; Meints, Kerstin; Mills, Daniel S

    2012-01-01

    Sensitivity to the emotions of others provides clear biological advantages. However, in the case of heterospecific relationships, such as that existing between dogs and humans, there are additional challenges since some elements of the expression of emotions are species-specific. Given that faces provide important visual cues for communicating emotional state in both humans and dogs, and that processing of emotions is subject to brain lateralisation, we investigated lateral gaze bias in adult dogs when presented with pictures of expressive human and dog faces. Our analysis revealed clear differences in laterality of eye movements in dogs towards conspecific faces according to the emotional valence of the expressions. Differences were also found towards human faces, but to a lesser extent. For comparative purpose, a similar experiment was also run with 4-year-old children and it was observed that they showed differential processing of facial expressions compared to dogs, suggesting a species-dependent engagement of the right or left hemisphere in processing emotions.

  7. E-gaze : create gaze communication for peoplewith visual disability

    NARCIS (Netherlands)

    Qiu, S.; Osawa, H.; Hu, J.; Rauterberg, G.W.M.

    2015-01-01

    Gaze signals are frequently used by the sighted in social interactions as visual cues. However, these signals and cues are hardly accessible for people with visual disability. A conceptual design of E-Gaze glasses is proposed, assistive to create gaze communication between blind and sighted people

  8. A GazeWatch Prototype

    DEFF Research Database (Denmark)

    Paulin Hansen, John; Biermann, Florian; Møllenbach, Emile

    2015-01-01

    We demonstrate potentials of adding a gaze tracking unit to a smartwatch, allowing hands-free interaction with the watch itself and control of the environment. Users give commands via gaze gestures, i.e. looking away and back to the GazeWatch. Rapid presentation of single words on the watch displ...... provides a rich and effective textual interface. Finally, we exemplify how the GazeWatch can be used as a ubiquitous pointer on large displays....

  9. Gazes and Performances

    DEFF Research Database (Denmark)

    Larsen, Jonas

    ethnographic studies I spell out the embodied, hybridised, mobile and performative nature of tourist gazing especially with regard to tourist photography. The talk draws on my recent book Tourism, Performance and the Everyday: Consuming the Orient (Routledge, 2009, With M. Haldrup) and the substantially......Abstract: Recent literature has critiqued this notion of the 'tourist gaze' for reducing tourism to visual experiences 'sightseeing' and neglecting other senses and bodily experiences of doing tourism. A so-called 'performance turn' within tourist studies highlights how tourists experience places...... to onceptualise the corporeality of tourist bodies and the embodied actions of and interactions between tourist workers, tourists and 'locals' on various stages. It has been suggested that it is necessary to choose between gazing and performing as the tourism paradigm (Perkin and Thorns 2001). Rather than...

  10. The Gaze as constituent and annihilator

    Directory of Open Access Journals (Sweden)

    Mats Carlsson

    2012-11-01

    Full Text Available This article aims to join the contemporary effort to promote a psychoanalytic renaissance within cinema studies, post Post-Theory. In trying to shake off the burden of the 1970s film theory's distortion of the Lacanian Gaze, rejuvenating it with the strength of the Real and fusing it with Freudian thoughts on the uncanny, hopefully this new dawn can be reached. I aspire to conceptualize the Gaze in a straightforward manner. This in order to obtain an instrument for the identification of certain strategies within the filmic realm aimed at depicting the subjective destabilizing of diegetic characters as well as thwarting techniques directed at the spectorial subject. In setting this capricious Gaze against the uncanny phenomena described by Freud, we find that these two ideas easily intertwine into a draft description of a powerful, potentially reconstitutive force worth being highlighted.

  11. Eye Movements in Gaze Interaction

    DEFF Research Database (Denmark)

    Møllenbach, Emilie; Hansen, John Paulin; Lillholm, Martin

    2013-01-01

    Gaze as a sole input modality must support complex navigation and selection tasks. Gaze interaction combines specific eye movements and graphic display objects (GDOs). This paper suggests a unifying taxonomy of gaze interaction principles. The taxonomy deals with three types of eye movements...

  12. The Epistemology of the Gaze

    DEFF Research Database (Denmark)

    Kramer, Mette

    2007-01-01

    In psycho-semiotic film theory the gaze is often considered to be a straitjacket for the female spectator. If we approach the gaze from an empiric so-called ‘naturalised’ lens, it is possible to regard the gaze as a functional devise through which the spectator can obtain knowledge essential for ...... for her self-preservation....

  13. Gaze-controlled Driving

    DEFF Research Database (Denmark)

    Tall, Martin; Alapetite, Alexandre; San Agustin, Javier

    2009-01-01

    We investigate if the gaze (point of regard) can control a remote vehicle driving on a racing track. Five different input devices (on-screen buttons, mouse-pointing low-cost webcam eye tracker and two commercial eye tracking systems) provide heading and speed control on the scene view transmitted...

  14. Gaze Interactive Building Instructions

    DEFF Research Database (Denmark)

    Hansen, John Paulin; Ahmed, Zaheer; Mardanbeigi, Diako

    We combine eye tracking technology and mobile tablets to support hands-free interaction with digital building instructions. As a proof-of-concept we have developed a small interactive 3D environment where one can interact with digital blocks by gaze, keystroke and head gestures. Blocks may be moved...

  15. "The Gaze Heuristic:" Biography of an Adaptively Rational Decision Process.

    Science.gov (United States)

    Hamlin, Robert P

    2017-04-01

    This article is a case study that describes the natural and human history of the gaze heuristic. The gaze heuristic is an interception heuristic that utilizes a single input (deviation from a constant angle of approach) repeatedly as a task is performed. Its architecture, advantages, and limitations are described in detail. A history of the gaze heuristic is then presented. In natural history, the gaze heuristic is the only known technique used by predators to intercept prey. In human history the gaze heuristic was discovered accidentally by Royal Air Force (RAF) fighter command just prior to World War II. As it was never discovered by the Luftwaffe, the technique conferred a decisive advantage upon the RAF throughout the war. After the end of the war in America, German technology was combined with the British heuristic to create the Sidewinder AIM9 missile, the most successful autonomous weapon ever built. There are no plans to withdraw it or replace its guiding gaze heuristic. The case study demonstrates that the gaze heuristic is a specific heuristic type that takes a single best input at the best time (take the best 2 ). Its use is an adaptively rational response to specific, rapidly evolving decision environments that has allowed those animals/humans/machines who use it to survive, prosper, and multiply relative to those who do not. Copyright © 2017 Cognitive Science Society, Inc.

  16. Proximity and Gaze Influences Facial Temperature: A Thermal Infrared Imaging Study.

    Directory of Open Access Journals (Sweden)

    Stephanos eIoannou

    2014-08-01

    Full Text Available Direct gaze and interpersonal proximity are known to lead to changes in psycho-physiology, behaviour and brain function. We know little, however, about subtler facial reactions such as rise and fall in temperature, which may be sensitive to contextual effects and functional in social interactions. Using thermal infrared imaging cameras 18 female adult participants were filmed at two interpersonal distances (intimate and social and two gaze conditions (averted and direct. The order of variation in distance was counterbalanced: half the participants experienced a female experimenter’s gaze at the social distance first before the intimate distance (a socially ‘normal’ order and half experienced the intimate distance first and then the social distance (an odd social order. At both distances averted gaze always preceded direct gaze. We found strong correlations in thermal changes between six areas of the face (forehead, chin, cheeks, nose, maxilliary and periorbital regions for all experimental conditions and developed a composite measure of thermal shifts for all analyses. Interpersonal proximity led to a thermal rise, but only in the ‘normal’ social order. Direct gaze, compared to averted gaze, led to a thermal increase at both distances with a stronger effect at intimate distance, in both orders of distance variation. Participants reported direct gaze as more intrusive than averted gaze, especially at the intimate distance. These results demonstrate the powerful effects of another person’s gaze on psycho-physiological responses, even at a distance and independent of context.

  17. Social eye gaze modulates processing of speech and co-speech gesture.

    Science.gov (United States)

    Holler, Judith; Schubotz, Louise; Kelly, Spencer; Hagoort, Peter; Schuetze, Manuela; Özyürek, Aslı

    2014-12-01

    In human face-to-face communication, language comprehension is a multi-modal, situated activity. However, little is known about how we combine information from different modalities during comprehension, and how perceived communicative intentions, often signaled through visual signals, influence this process. We explored this question by simulating a multi-party communication context in which a speaker alternated her gaze between two recipients. Participants viewed speech-only or speech+gesture object-related messages when being addressed (direct gaze) or unaddressed (gaze averted to other participant). They were then asked to choose which of two object images matched the speaker's preceding message. Unaddressed recipients responded significantly more slowly than addressees for speech-only utterances. However, perceiving the same speech accompanied by gestures sped unaddressed recipients up to a level identical to that of addressees. That is, when unaddressed recipients' speech processing suffers, gestures can enhance the comprehension of a speaker's message. We discuss our findings with respect to two hypotheses attempting to account for how social eye gaze may modulate multi-modal language comprehension. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. EYE GAZE TRACKING

    DEFF Research Database (Denmark)

    2017-01-01

    This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

  19. Toward understanding social cues and signals in human?robot interaction: effects of robot gaze and proxemic behavior

    OpenAIRE

    Fiore, Stephen M.; Wiltshire, Travis J.; Lobato, Emilio J. C.; Jentsch, Florian G.; Huang, Wesley H.; Axelrod, Benjamin

    2013-01-01

    As robots are increasingly deployed in settings requiring social interaction, research is needed to examine the social signals perceived by humans when robots display certain social cues. In this paper, we report a study designed to examine how humans interpret social cues exhibited by robots. We first provide a brief overview of perspectives from social cognition in humans and how these processes are applicable to human–robot interaction (HRI). We then discuss the need to examine the relatio...

  20. The “Social Gaze Space”: A Taxonomy for Gaze-Based Communication in Triadic Interactions

    Directory of Open Access Journals (Sweden)

    Mathis Jording

    2018-02-01

    Full Text Available Humans substantially rely on non-verbal cues in their communication and interaction with others. The eyes represent a “simultaneous input-output device”: While we observe others and obtain information about their mental states (including feelings, thoughts, and intentions-to-act, our gaze simultaneously provides information about our own attention and inner experiences. This substantiates its pivotal role for the coordination of communication. The communicative and coordinative capacities – and their phylogenetic and ontogenetic impacts – become fully apparent in triadic interactions constituted in its simplest form by two persons and an object. Technological advances have sparked renewed interest in social gaze and provide new methodological approaches. Here we introduce the ‘Social Gaze Space’ as a new conceptual framework for the systematic study of gaze behavior during social information processing. It covers all possible categorical states, namely ‘partner-oriented,’ ‘object-oriented,’ ‘introspective,’ ‘initiating joint attention,’ and ‘responding joint attention.’ Different combinations of these states explain several interpersonal phenomena. We argue that this taxonomy distinguishes the most relevant interactional states along their distinctive features, and will showcase the implications for prominent social gaze phenomena. The taxonomy allows to identify research desiderates that have been neglected so far. We argue for a systematic investigation of these phenomena and discuss some related methodological issues.

  1. Watch out! Magnetoencephalographic evidence for early modulation of attention orienting by fearful gaze cueing.

    Directory of Open Access Journals (Sweden)

    Fanny Lachat

    Full Text Available Others' gaze and emotional facial expression are important cues for the process of attention orienting. Here, we investigated with magnetoencephalography (MEG whether the combination of averted gaze and fearful expression may elicit a selectively early effect of attention orienting on the brain responses to targets. We used the direction of gaze of centrally presented fearful and happy faces as the spatial attention orienting cue in a Posner-like paradigm where the subjects had to detect a target checkerboard presented at gazed-at (valid trials or non gazed-at (invalid trials locations of the screen. We showed that the combination of averted gaze and fearful expression resulted in a very early attention orienting effect in the form of additional parietal activity between 55 and 70 ms for the valid versus invalid targets following fearful gaze cues. No such effect was obtained for the targets following happy gaze cues. This early cue-target validity effect selective of fearful gaze cues involved the left superior parietal region and the left lateral middle occipital region. These findings provide the first evidence for an effect of attention orienting induced by fearful gaze in the time range of C1. In doing so, they demonstrate the selective impact of combined gaze and fearful expression cues in the process of attention orienting.

  2. Demo of Gaze Controlled Flying

    DEFF Research Database (Denmark)

    Alapetite, Alexandre; Hansen, John Paulin; Scott MacKenzie, I.

    2012-01-01

    Development of a control paradigm for unmanned aerial vehicles (UAV) is a new challenge to HCI. The demo explores how to use gaze as input for locomotion in 3D. A low-cost drone will be controlled by tracking user’s point of regard (gaze) on a live video stream from the UAV.......Development of a control paradigm for unmanned aerial vehicles (UAV) is a new challenge to HCI. The demo explores how to use gaze as input for locomotion in 3D. A low-cost drone will be controlled by tracking user’s point of regard (gaze) on a live video stream from the UAV....

  3. Real-time non-invasive eyetracking and gaze-point determination for human-computer interaction and biomedicine

    Science.gov (United States)

    Talukder, Ashit; Morookian, John-Michael; Monacos, S.; Lam, R.; Lebaw, C.; Bond, A.

    2004-01-01

    Eyetracking is one of the latest technologies that has shown potential in several areas including human-computer interaction for people with and without disabilities, and for noninvasive monitoring, detection, and even diagnosis of physiological and neurological problems in individuals.

  4. Investigating gaze-controlled input in a cognitive selection test

    OpenAIRE

    Gayraud, Katja; Hasse, Catrin; Eißfeldt, Hinnerk; Pannasch, Sebastian

    2017-01-01

    In the field of aviation, there is a growing interest in developing more natural forms of interaction between operators and systems to enhance safety and efficiency. These efforts also include eye gaze as an input channel for human-machine interaction. The present study investigates the application of gaze-controlled input in a cognitive selection test called Eye Movement Conflict Detection Test. The test enables eye movements to be studied as an indicator for psychological test performance a...

  5. CULTURAL DISPLAY RULES DRIVE EYE GAZE DURING THINKING.

    Science.gov (United States)

    McCarthy, Anjanie; Lee, Kang; Itakura, Shoji; Muir, Darwin W

    2006-11-01

    The authors measured the eye gaze displays of Canadian, Trinidadian, and Japanese participants as they answered questions for which they either knew, or had to derive, the answers. When they knew the answers, Trinidadians maintained the most eye contact, whereas Japanese maintained the least. When thinking about the answers to questions, Canadians and Trinidadians looked up, whereas Japanese looked down. Thus, for humans, gaze displays while thinking are at least in part culturally determined.

  6. Human sensitivity to eye contact in 2D and 3D videoconferencing

    NARCIS (Netherlands)

    Eijk, van R.L.J.; Kuijsters, A.; Dijkstra, K.I.; IJsselsteijn, W.A.

    2010-01-01

    Gaze awareness and eye contact serve important functions in social interaction. In order to maintain those functions in 2D and 3D videoconferencing systems, human sensitivity to eye contact and gaze direction needs to be taken into account in the design of such systems. Here we experimentally

  7. Interaction between gaze and visual and proprioceptive position judgements.

    Science.gov (United States)

    Fiehler, Katja; Rösler, Frank; Henriques, Denise Y P

    2010-06-01

    There is considerable evidence that targets for action are represented in a dynamic gaze-centered frame of reference, such that each gaze shift requires an internal updating of the target. Here, we investigated the effect of eye movements on the spatial representation of targets used for position judgements. Participants had their hand passively placed to a location, and then judged whether this location was left or right of a remembered visual or remembered proprioceptive target, while gaze direction was varied. Estimates of position of the remembered targets relative to the unseen position of the hand were assessed with an adaptive psychophysical procedure. These positional judgements significantly varied relative to gaze for both remembered visual and remembered proprioceptive targets. Our results suggest that relative target positions may also be represented in eye-centered coordinates. This implies similar spatial reference frames for action control and space perception when positions are coded relative to the hand.

  8. Affine Transform to Reform Pixel Coordinates of EOG Signals for Controlling Robot Manipulators Using Gaze Motions

    Directory of Open Access Journals (Sweden)

    Muhammad Ilhamdi Rusydi

    2014-06-01

    Full Text Available Biosignals will play an important role in building communication between machines and humans. One of the types of biosignals that is widely used in neuroscience are electrooculography (EOG signals. An EOG has a linear relationship with eye movement displacement. Experiments were performed to construct a gaze motion tracking method indicated by robot manipulator movements. Three operators looked at 24 target points displayed on a monitor that was 40 cm in front of them. Two channels (Ch1 and Ch2 produced EOG signals for every single eye movement. These signals were converted to pixel units by using the linear relationship between EOG signals and gaze motion distances. The conversion outcomes were actual pixel locations. An affine transform method is proposed to determine the shift of actual pixels to target pixels. This method consisted of sequences of five geometry processes, which are translation-1, rotation, translation-2, shear and dilatation. The accuracy was approximately 0.86° ± 0.67° in the horizontal direction and 0.54° ± 0.34° in the vertical. This system successfully tracked the gaze motions not only in direction, but also in distance. Using this system, three operators could operate a robot manipulator to point at some targets. This result shows that the method is reliable in building communication between humans and machines using EOGs.

  9. Affine transform to reform pixel coordinates of EOG signals for controlling robot manipulators using gaze motions.

    Science.gov (United States)

    Rusydi, Muhammad Ilhamdi; Sasaki, Minoru; Ito, Satoshi

    2014-06-10

    Biosignals will play an important role in building communication between machines and humans. One of the types of biosignals that is widely used in neuroscience are electrooculography (EOG) signals. An EOG has a linear relationship with eye movement displacement. Experiments were performed to construct a gaze motion tracking method indicated by robot manipulator movements. Three operators looked at 24 target points displayed on a monitor that was 40 cm in front of them. Two channels (Ch1 and Ch2) produced EOG signals for every single eye movement. These signals were converted to pixel units by using the linear relationship between EOG signals and gaze motion distances. The conversion outcomes were actual pixel locations. An affine transform method is proposed to determine the shift of actual pixels to target pixels. This method consisted of sequences of five geometry processes, which are translation-1, rotation, translation-2, shear and dilatation. The accuracy was approximately 0.86° ± 0.67° in the horizontal direction and 0.54° ± 0.34° in the vertical. This system successfully tracked the gaze motions not only in direction, but also in distance. Using this system, three operators could operate a robot manipulator to point at some targets. This result shows that the method is reliable in building communication between humans and machines using EOGs.

  10. Human-directed aggression in the cat.

    Science.gov (United States)

    Curtis, Terry Marie

    2008-09-01

    Feline aggression-between cats or directed at humans-is, after inappropriate elimination and urine-marking behaviors, the second most common reason cats are seen by behavioral specialists. For diagnosis and treatment it is important to determine the motivation for the aggression. The more common causes for human-directed aggression in cats include play, fear, petting intolerance, and redirected aggression. Other causes include pain and maternal behavior. Sexually motivated and status related aggression are much more rare. Treatment includes a combination of behavioral modification, environmental modification, and, in some cases, medication.

  11. Assessing the Usability of Gaze-Adapted Interface against Conventional Eye-based Input Emulation

    OpenAIRE

    Kumar, Chandan; Menges, Raphael; Staab, Steffen

    2017-01-01

    In recent years, eye tracking systems have greatly improved, beginning to play a promising role as an input medium. Eye trackers can be used for application control either by simply emulating the mouse and keyboard devices in the traditional graphical user interface, or by customized interfaces for eye gaze events. In this work, we evaluate these two approaches to assess their impact in usability. We present a gaze-adapted Twitter application interface with direct interaction of eye gaze inpu...

  12. Conflict Tasks of Different Types Divergently Affect the Attentional Processing of Gaze and Arrow.

    Science.gov (United States)

    Fan, Lingxia; Yu, Huan; Zhang, Xuemin; Feng, Qing; Sun, Mengdan; Xu, Mengsi

    2018-01-01

    The present study explored the attentional processing mechanisms of gaze and arrow cues in two different types of conflict tasks. In Experiment 1, participants performed a flanker task in which gaze and arrow cues were presented as central targets or bilateral distractors. The congruency between the direction of the target and the distractors was manipulated. Results showed that arrow distractors greatly interfered with the attentional processing of gaze, while the processing of arrow direction was immune to conflict from gaze distractors. Using a spatial compatibility task, Experiment 2 explored the conflict effects exerted on gaze and arrow processing by their relative spatial locations. When the direction of the arrow was in conflict with its spatial layout on screen, response times were slowed; however, the encoding of gaze was unaffected by spatial location. In general, processing to an arrow cue is less influenced by bilateral gaze cues but is affected by irrelevant spatial information, while processing to a gaze cue is greatly disturbed by bilateral arrows but is unaffected by irrelevant spatial information. Different effects on gaze and arrow cues by different types of conflicts may reflect two relatively distinct specific modes of the attentional process.

  13. The effects of social pressure and emotional expression on the cone of gaze in patients with social anxiety disorder.

    Science.gov (United States)

    Harbort, Johannes; Spiegel, Julia; Witthöft, Michael; Hecht, Heiko

    2017-06-01

    Patients with social anxiety disorder suffer from pronounced fears in social situations. As gaze perception is crucial in these situations, we examined which factors influence the range of gaze directions where mutual gaze is experienced (the cone of gaze). The social stimulus was modified by changing the number of people (heads) present and the emotional expression of their faces. Participants completed a psychophysical task, in which they had to adjust the eyes of a virtual head to gaze at the edge of the range where mutual eye-contact was experienced. The number of heads affected the width of the gaze cone: the more heads, the wider the gaze cone. The emotional expression of the virtual head had no consistent effect on the width of the gaze cone, it did however affect the emotional state of the participants. Angry expressions produced the highest arousal values. Highest valence emerged from happy faces, lowest valence from angry faces. These results suggest that the widening of the gaze cone in social anxiety disorder is not primarily mediated by their altered emotional reactivity. Implications for gaze assessment and gaze training in therapeutic contexts are discussed. Due to interindividual variability, enlarged gaze cones are not necessarily indicative of social anxiety disorder, they merely constitute a correlate at the group level. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Postural sway and gaze can track the complex motion of a visual target.

    Directory of Open Access Journals (Sweden)

    Vassilia Hatzitaki

    Full Text Available Variability is an inherent and important feature of human movement. This variability has form exhibiting a chaotic structure. Visual feedback training using regular predictive visual target motions does not take into account this essential characteristic of the human movement, and may result in task specific learning and loss of visuo-motor adaptability. In this study, we asked how well healthy young adults can track visual target cues of varying degree of complexity during whole-body swaying in the Anterior-Posterior (AP and Medio-Lateral (ML direction. Participants were asked to track three visual target motions: a complex (Lorenz attractor, a noise (brown and a periodic (sine moving target while receiving online visual feedback about their performance. Postural sway, gaze and target motion were synchronously recorded and the degree of force-target and gaze-target coupling was quantified using spectral coherence and Cross-Approximate entropy. Analysis revealed that both force-target and gaze-target coupling was sensitive to the complexity of the visual stimuli motions. Postural sway showed a higher degree of coherence with the Lorenz attractor than the brown noise or sinusoidal stimulus motion. Similarly, gaze was more synchronous with the Lorenz attractor than the brown noise and sinusoidal stimulus motion. These results were similar regardless of whether tracking was performed in the AP or ML direction. Based on the theoretical model of optimal movement variability tracking of a complex signal may provide a better stimulus to improve visuo-motor adaptation and learning in postural control.

  15. Gaze behaviour during space perception and spatial decision making.

    Science.gov (United States)

    Wiener, Jan M; Hölscher, Christoph; Büchner, Simon; Konieczny, Lars

    2012-11-01

    A series of four experiments investigating gaze behavior and decision making in the context of wayfinding is reported. Participants were presented with screenshots of choice points taken in large virtual environments. Each screenshot depicted alternative path options. In Experiment 1, participants had to decide between them to find an object hidden in the environment. In Experiment 2, participants were first informed about which path option to take as if following a guided route. Subsequently, they were presented with the same images in random order and had to indicate which path option they chose during initial exposure. In Experiment 1, we demonstrate (1) that participants have a tendency to choose the path option that featured the longer line of sight, and (2) a robust gaze bias towards the eventually chosen path option. In Experiment 2, systematic differences in gaze behavior towards the alternative path options between encoding and decoding were observed. Based on data from Experiments 1 and 2 and two control experiments ensuring that fixation patterns were specific to the spatial tasks, we develop a tentative model of gaze behavior during wayfinding decision making suggesting that particular attention was paid to image areas depicting changes in the local geometry of the environments such as corners, openings, and occlusions. Together, the results suggest that gaze during a wayfinding tasks is directed toward, and can be predicted by, a subset of environmental features and that gaze bias effects are a general phenomenon of visual decision making.

  16. Method of Menu Selection by Gaze Movement Using AC EOG Signals

    Science.gov (United States)

    Kanoh, Shin'ichiro; Futami, Ryoko; Yoshinobu, Tatsuo; Hoshimiya, Nozomu

    A method to detect the direction and the distance of voluntary eye gaze movement from EOG (electrooculogram) signals was proposed and tested. In this method, AC-amplified vertical and horizontal transient EOG signals were classified into 8-class directions and 2-class distances of voluntary eye gaze movements. A horizontal and a vertical EOGs during eye gaze movement at each sampling time were treated as a two-dimensional vector, and the center of gravity of the sample vectors whose norms were more than 80% of the maximum norm was used as a feature vector to be classified. By the classification using the k-nearest neighbor algorithm, it was shown that the averaged correct detection rates on each subject were 98.9%, 98.7%, 94.4%, respectively. This method can avoid strict EOG-based eye tracking which requires DC amplification of very small signal. It would be useful to develop robust human interfacing systems based on menu selection for severely paralyzed patients.

  17. Human-Robot Interaction Directed Research Project

    Science.gov (United States)

    Rochlis, Jennifer; Ezer, Neta; Sandor, Aniko

    2011-01-01

    Human-robot interaction (HRI) is about understanding and shaping the interactions between humans and robots (Goodrich & Schultz, 2007). It is important to evaluate how the design of interfaces and command modalities affect the human s ability to perform tasks accurately, efficiently, and effectively (Crandall, Goodrich, Olsen Jr., & Nielsen, 2005) It is also critical to evaluate the effects of human-robot interfaces and command modalities on operator mental workload (Sheridan, 1992) and situation awareness (Endsley, Bolt , & Jones, 2003). By understanding the effects of interface design on human performance, workload, and situation awareness, interfaces can be developed that support the human in performing tasks with minimal errors and with appropriate interaction time and effort. Thus, the results of research on human-robot interfaces have direct implications for design. Because the factors associated with interfaces and command modalities in HRI are too numerous to address in 3 years of research, the proposed research concentrates on three manageable areas applicable to National Aeronautics and Space Administration (NASA) robot systems. These topic areas emerged from the Fiscal Year (FY) 2011 work that included extensive literature reviews and observations of NASA systems. The three topic areas are: 1) video overlays, 2) camera views, and 3) command modalities. Each area is described in detail below, along with relevance to existing NASA human-robot systems. In addition to studies in these three topic areas, a workshop is proposed for FY12. The workshop will bring together experts in human-robot interaction and robotics to discuss the state of the practice as applicable to research in space robotics. Studies proposed in the area of video overlays consider two factors in the implementation of augmented reality (AR) for operator displays during teleoperation. The first of these factors is the type of navigational guidance provided by AR symbology. In the proposed

  18. Simple gaze-contingent cues guide eye movements in a realistic driving simulator

    Science.gov (United States)

    Pomarjanschi, Laura; Dorr, Michael; Bex, Peter J.; Barth, Erhardt

    2013-03-01

    Looking at the right place at the right time is a critical component of driving skill. Therefore, gaze guidance has the potential to become a valuable driving assistance system. In previous work, we have already shown that complex gaze-contingent stimuli can guide attention and reduce the number of accidents in a simple driving simulator. We here set out to investigate whether cues that are simple enough to be implemented in a real car can also capture gaze during a more realistic driving task in a high-fidelity driving simulator. We used a state-of-the-art, wide-field-of-view driving simulator with an integrated eye tracker. Gaze-contingent warnings were implemented using two arrays of light-emitting diodes horizontally fitted below and above the simulated windshield. Thirteen volunteering subjects drove along predetermined routes in a simulated environment popu­ lated with autonomous traffic. Warnings were triggered during the approach to half of the intersections, cueing either towards the right or to the left. The remaining intersections were not cued, and served as controls. The analysis of the recorded gaze data revealed that the gaze-contingent cues did indeed have a gaze guiding effect, triggering a significant shift in gaze position towards the highlighted direction. This gaze shift was not accompanied by changes in driving behaviour, suggesting that the cues do not interfere with the driving task itself.

  19. The Relationship between Children's Gaze Reporting and Theory of Mind

    Science.gov (United States)

    D'Entremont, Barbara; Seamans, Elizabeth; Boudreau, Elyse

    2012-01-01

    Seventy-nine 3- and 4-year-old children were tested on gaze-reporting ability and Wellman and Liu's (2004) continuous measure of theory of mind (ToM). Children were better able to report where someone was looking when eye and head direction were provided as a cue compared with when only eye direction cues were provided. With the exception of…

  20. The Gaze-Cueing Effect in the United States and Japan: Influence of Cultural Differences in Cognitive Strategies on Control of Attention

    OpenAIRE

    Saki Takao; Yusuke Yamani; Atsunori Ariga

    2018-01-01

    The direction of gaze automatically and exogenously guides visual spatial attention, a phenomenon termed as the gaze-cueing effect. Although this effect arises when the duration of stimulus onset asynchrony (SOA) between a non-predictive gaze cue and the target is relatively long, no empirical research has examined the factors underlying this extended cueing effect. Two experiments compared the gaze-cueing effect at longer SOAs (700 ms) in Japanese and American participants. Cross-cultural st...

  1. [Advance directives, a tool to humanize care].

    Science.gov (United States)

    Olmari-Ebbing, M; Zumbach, C N; Forest, M I; Rapin, C H

    2000-07-01

    The relationship between the patient and a medical care giver is complex specially as it implies to the human, juridical and practical points of view. It depends on legal and deontological considerations, but also on professional habits. Today, we are confronted to a fundamental modification of this relationship. Professional guidelines exist, but are rarely applied and rarely taught in universities. However, patients are eager to move from a paternalistic relationship to a true partnership, more harmonious and more respectful of individual values ("value based medicine"). Advance directives give us an opportunity to improve our practices and to provide care consistent with the needs and wishes of each patient.

  2. The duality of gaze: Eyes extract and signal social information during sustained cooperative and competitive dyadic gaze

    Directory of Open Access Journals (Sweden)

    Michelle eJarick

    2015-09-01

    Full Text Available In contrast to nonhuman primate eyes, which have a dark sclera surrounding a dark iris, human eyes have a white sclera that surrounds a dark iris. This high contrast morphology allows humans to determine quickly and easily where others are looking and infer what they are attending to. In recent years an enormous body of work has used photos and schematic images of faces to study these aspects of social attention, e.g., the selection of the eyes of others and the shift of attention to where those eyes are directed. However, evolutionary theory holds that humans did not develop a high contrast morphology simply to use the eyes of others as attentional cues; rather they sacrificed camouflage for communication, that is, to signal their thoughts and intentions to others. In the present study we demonstrate the importance of this by taking as our starting point the hypothesis that a cornerstone of nonverbal communication is the eye contact between individuals and the time that it is held. In a single simple study we show experimentally that the effect of eye contact can be quickly and profoundly altered merely by having participants, who had never met before, play a game in a cooperative or competitive manner. After the game participants were asked to make eye contact for a prolonged period of time (10 minutes. Those who had played the game cooperatively found this terribly difficult to do, repeatedly talking and breaking gaze. In contrast, those who had played the game competitively were able to stare quietly at each other for a sustained period. Collectively these data demonstrate that when looking at the eyes of a real person one both acquires and signals information to the other person. This duality of gaze is critical to nonverbal communication, with the nature of that communication shaped by the relationship between individuals, e.g., cooperative or competitive.

  3. New perspectives in gaze sensitivity research.

    Science.gov (United States)

    Davidson, Gabrielle L; Clayton, Nicola S

    2016-03-01

    Attending to where others are looking is thought to be of great adaptive benefit for animals when avoiding predators and interacting with group members. Many animals have been reported to respond to the gaze of others, by co-orienting their gaze with group members (gaze following) and/or responding fearfully to the gaze of predators or competitors (i.e., gaze aversion). Much of the literature has focused on the cognitive underpinnings of gaze sensitivity, namely whether animals have an understanding of the attention and visual perspectives in others. Yet there remain several unanswered questions regarding how animals learn to follow or avoid gaze and how experience may influence their behavioral responses. Many studies on the ontogeny of gaze sensitivity have shed light on how and when gaze abilities emerge and change across development, indicating the necessity to explore gaze sensitivity when animals are exposed to additional information from their environment as adults. Gaze aversion may be dependent upon experience and proximity to different predator types, other cues of predation risk, and the salience of gaze cues. Gaze following in the context of information transfer within social groups may also be dependent upon experience with group-members; therefore we propose novel means to explore the degree to which animals respond to gaze in a flexible manner, namely by inhibiting or enhancing gaze following responses. We hope this review will stimulate gaze sensitivity research to expand beyond the narrow scope of investigating underlying cognitive mechanisms, and to explore how gaze cues may function to communicate information other than attention.

  4. Human movement is both diffusive and directed.

    Directory of Open Access Journals (Sweden)

    Mark Padgham

    Full Text Available Understanding the influence of the built environment on human movement requires quantifying spatial structure in a general sense. Because of the difficulty of this task, studies of movement dynamics often ignore spatial heterogeneity and treat movement through journey lengths or distances alone. This study analyses public bicycle data from central London to reveal that, although journey distances, directions, and frequencies of occurrence are spatially variable, their relative spatial patterns remain largely constant, suggesting the influence of a fixed spatial template. A method is presented to describe this underlying space in terms of the relative orientation of movements toward, away from, and around locations of geographical or cultural significance. This produces two fields: one of convergence and one of divergence, which are able to accurately reconstruct the observed spatial variations in movement. These two fields also reveal categorical distinctions between shorter journeys merely serving diffusion away from significant locations, and longer journeys intentionally serving transport between spatially distinct centres of collective importance. Collective patterns of human movement are thus revealed to arise from a combination of both diffusive and directed movement, with aggregate statistics such as mean travel distances primarily determined by relative numbers of these two kinds of journeys.

  5. The Effectiveness of Gaze-Contingent Control in Computer Games.

    Science.gov (United States)

    Orlov, Paul A; Apraksin, Nikolay

    2015-01-01

    Eye-tracking technology and gaze-contingent control in human-computer interaction have become an objective reality. This article reports on a series of eye-tracking experiments, in which we concentrated on one aspect of gaze-contingent interaction: Its effectiveness compared with mouse-based control in a computer strategy game. We propose a measure for evaluating the effectiveness of interaction based on "the time of recognition" the game unit. In this article, we use this measure to compare gaze- and mouse-contingent systems, and we present the analysis of the differences as a function of the number of game units. Our results indicate that performance of gaze-contingent interaction is typically higher than mouse manipulation in a visual searching task. When tested on 60 subjects, the results showed that the effectiveness of gaze-contingent systems over 1.5 times higher. In addition, we obtained that eye behavior stays quite stabile with or without mouse interaction. © The Author(s) 2015.

  6. Investigating gaze of children with ASD in naturalistic settings.

    Directory of Open Access Journals (Sweden)

    Basilio Noris

    Full Text Available BACKGROUND: Visual behavior is known to be atypical in Autism Spectrum Disorders (ASD. Monitor-based eye-tracking studies have measured several of these atypicalities in individuals with Autism. While atypical behaviors are known to be accentuated during natural interactions, few studies have been made on gaze behavior in natural interactions. In this study we focused on i whether the findings done in laboratory settings are also visible in a naturalistic interaction; ii whether new atypical elements appear when studying visual behavior across the whole field of view. METHODOLOGY/PRINCIPAL FINDINGS: Ten children with ASD and ten typically developing children participated in a dyadic interaction with an experimenter administering items from the Early Social Communication Scale (ESCS. The children wore a novel head-mounted eye-tracker, measuring gaze direction and presence of faces across the child's field of view. The analysis of gaze episodes to faces revealed that children with ASD looked significantly less and for shorter lapses of time at the experimenter. The analysis of gaze patterns across the child's field of view revealed that children with ASD looked downwards and made more extensive use of their lateral field of view when exploring the environment. CONCLUSIONS/SIGNIFICANCE: The data gathered in naturalistic settings confirm findings previously obtained only in monitor-based studies. Moreover, the study allowed to observe a generalized strategy of lateral gaze in children with ASD when they were looking at the objects in their environment.

  7. Experimental test of spatial updating models for monkey eye-head gaze shifts.

    Directory of Open Access Journals (Sweden)

    Tom J Van Grootel

    Full Text Available How the brain maintains an accurate and stable representation of visual target locations despite the occurrence of saccadic gaze shifts is a classical problem in oculomotor research. Here we test and dissociate the predictions of different conceptual models for head-unrestrained gaze-localization behavior of macaque monkeys. We adopted the double-step paradigm with rapid eye-head gaze shifts to measure localization accuracy in response to flashed visual stimuli in darkness. We presented the second target flash either before (static, or during (dynamic the first gaze displacement. In the dynamic case the brief visual flash induced a small retinal streak of up to about 20 deg at an unpredictable moment and retinal location during the eye-head gaze shift, which provides serious challenges for the gaze-control system. However, for both stimulus conditions, monkeys localized the flashed targets with accurate gaze shifts, which rules out several models of visuomotor control. First, these findings exclude the possibility that gaze-shift programming relies on retinal inputs only. Instead, they support the notion that accurate eye-head motor feedback updates the gaze-saccade coordinates. Second, in dynamic trials the visuomotor system cannot rely on the coordinates of the planned first eye-head saccade either, which rules out remapping on the basis of a predictive corollary gaze-displacement signal. Finally, because gaze-related head movements were also goal-directed, requiring continuous access to eye-in-head position, we propose that our results best support a dynamic feedback scheme for spatial updating in which visuomotor control incorporates accurate signals about instantaneous eye- and head positions rather than relative eye- and head displacements.

  8. Gaze strategy in the free flying zebra finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Dennis Eckmeier

    Full Text Available Fast moving animals depend on cues derived from the optic flow on their retina. Optic flow from translational locomotion includes information about the three-dimensional composition of the environment, while optic flow experienced during a rotational self motion does not. Thus, a saccadic gaze strategy that segregates rotations from translational movements during locomotion will facilitate extraction of spatial information from the visual input. We analysed whether birds use such a strategy by highspeed video recording zebra finches from two directions during an obstacle avoidance task. Each frame of the recording was examined to derive position and orientation of the beak in three-dimensional space. The data show that in all flights the head orientation was shifted in a saccadic fashion and was kept straight between saccades. Therefore, birds use a gaze strategy that actively stabilizes their gaze during translation to simplify optic flow based navigation. This is the first evidence of birds actively optimizing optic flow during flight.

  9. Creating Gaze Annotations in Head Mounted Displays

    DEFF Research Database (Denmark)

    Mardanbeigi, Diako; Qvarfordt, Pernilla

    2015-01-01

    To facilitate distributed communication in mobile settings, we developed GazeNote for creating and sharing gaze annotations in head mounted displays (HMDs). With gaze annotations it possible to point out objects of interest within an image and add a verbal description. To create an annota- tion...

  10. Eye Gaze in Creative Sign Language

    Science.gov (United States)

    Kaneko, Michiko; Mesch, Johanna

    2013-01-01

    This article discusses the role of eye gaze in creative sign language. Because eye gaze conveys various types of linguistic and poetic information, it is an intrinsic part of sign language linguistics in general and of creative signing in particular. We discuss various functions of eye gaze in poetic signing and propose a classification of gaze…

  11. A Gaze Interactive Textual Smartwatch Interface

    DEFF Research Database (Denmark)

    Hansen, John Paulin; Biermann, Florian; Askø Madsen, Janus

    2015-01-01

    Mobile gaze interaction is challenged by inherent motor noise. We examined the gaze tracking accuracy and precision of twelve subjects wearing a gaze tracker on their wrist while standing and walking. Results suggest that it will be possible to detect whether people are glancing the watch, but no...

  12. TabletGaze: Unconstrained Appearance-based Gaze Estimation in Mobile Tablets

    OpenAIRE

    Huang, Qiong; Veeraraghavan, Ashok; Sabharwal, Ashutosh

    2015-01-01

    We study gaze estimation on tablets, our key design goal is uncalibrated gaze estimation using the front-facing camera during natural use of tablets, where the posture and method of holding the tablet is not constrained. We collected the first large unconstrained gaze dataset of tablet users, labeled Rice TabletGaze dataset. The dataset consists of 51 subjects, each with 4 different postures and 35 gaze locations. Subjects vary in race, gender and in their need for prescription glasses, all o...

  13. Direct numerical simulation of human phonation

    Science.gov (United States)

    Bodony, Daniel; Saurabh, Shakti

    2017-11-01

    The generation and propagation of the human voice in three-dimensions is studied using direct numerical simulation. A full body domain is employed for the purpose of directly computing the sound in the region past the speaker's mouth. The air in the vocal tract is modeled as a compressible and viscous fluid interacting with the elastic vocal folds. The vocal fold tissue material properties are multi-layered, with varying stiffness, and a linear elastic transversely isotropic model is utilized and implemented in a quadratic finite element code. The fluid-solid domains are coupled through a boundary-fitted interface and utilize a Poisson equation-based mesh deformation method. A kinematic constraint based on a specified minimum gap between the vocal folds is applied to prevent collision during glottal closure. Both near VF flow dynamics and far-field acoustics have been studied. A comparison is drawn to current two-dimensional simulations as well as to data from the literature. Near field vocal fold dynamics and glottal flow results are studied and in good agreement with previous three-dimensional phonation studies. Far-field acoustic characteristics, when compared to their two-dimensional counterpart, are shown to be sensitive to the dimensionality. Supported by the National Science Foundation (CAREER Award Number 1150439).

  14. Human-Robot Interaction Directed Research Project

    Science.gov (United States)

    Sandor, Aniko; Cross, Ernest V., II; Chang, Mai Lee

    2014-01-01

    Human-robot interaction (HRI) is a discipline investigating the factors affecting the interactions between humans and robots. It is important to evaluate how the design of interfaces and command modalities affect the human's ability to perform tasks accurately, efficiently, and effectively when working with a robot. By understanding the effects of interface design on human performance, workload, and situation awareness, interfaces can be developed to appropriately support the human in performing tasks with minimal errors and with appropriate interaction time and effort. Thus, the results of research on human-robot interfaces have direct implications for the design of robotic systems. This DRP concentrates on three areas associated with interfaces and command modalities in HRI which are applicable to NASA robot systems: 1) Video Overlays, 2) Camera Views, and 3) Command Modalities. The first study focused on video overlays that investigated how Augmented Reality (AR) symbology can be added to the human-robot interface to improve teleoperation performance. Three types of AR symbology were explored in this study, command guidance (CG), situation guidance (SG), and both (SCG). CG symbology gives operators explicit instructions on what commands to input, whereas SG symbology gives operators implicit cues so that operators can infer the input commands. The combination of CG and SG provided operators with explicit and implicit cues allowing the operator to choose which symbology to utilize. The objective of the study was to understand how AR symbology affects the human operator's ability to align a robot arm to a target using a flight stick and the ability to allocate attention between the symbology and external views of the world. The study evaluated the effects type of symbology (CG and SG) has on operator tasks performance and attention allocation during teleoperation of a robot arm. The second study expanded on the first study by evaluating the effects of the type of

  15. Investigating social gaze as an action-perception online performance.

    Science.gov (United States)

    Grynszpan, Ouriel; Simonin, Jérôme; Martin, Jean-Claude; Nadel, Jacqueline

    2012-01-01

    Gaze represents a major non-verbal communication channel in social interactions. In this respect, when facing another person, one's gaze should not be examined as a purely perceptive process but also as an action-perception online performance. However, little is known about processes involved in the real-time self-regulation of social gaze. The present study investigates the impact of a gaze-contingent viewing window on fixation patterns and the awareness of being the agent moving the window. In face-to-face scenarios played by a virtual human character, the task for the 18 adult participants was to interpret an equivocal sentence which could be disambiguated by examining the emotional expressions of the character speaking. The virtual character was embedded in naturalistic backgrounds to enhance realism. Eye-tracking data showed that the viewing window induced changes in gaze behavior, notably longer visual fixations. Notwithstanding, only half of the participants ascribed the window displacements to their eye movements. These participants also spent more time looking at the eyes and mouth regions of the virtual human character. The outcomes of the study highlight the dissociation between non-volitional gaze adaptation and the self-ascription of agency. Such dissociation provides support for a two-step account of the sense of agency composed of pre-noetic monitoring mechanisms and reflexive processes, linked by bottom-up and top-down processes. We comment upon these results, which illustrate the relevance of our method for studying online social cognition, in particular concerning autism spectrum disorders (ASD) where the poor pragmatic understanding of oral speech is considered linked to visual peculiarities that impede facial exploration.

  16. Towards emotion modeling based on gaze dynamics in generic interfaces

    DEFF Research Database (Denmark)

    Vester-Christensen, Martin; Leimberg, Denis; Ersbøll, Bjarne Kjær

    2005-01-01

    Gaze detection can be a useful ingredient in generic human computer interfaces if current technical barriers are overcome. We discuss the feasibility of concurrent posture and eye-tracking in the context of single (low cost) camera imagery. The ingredients in the approach are posture and eye region...

  17. Gaze Embeddings for Zero-Shot Image Classification

    NARCIS (Netherlands)

    Karessli, N.; Akata, Z.; Schiele, B.; Bulling, A.

    2017-01-01

    Zero-shot image classification using auxiliary information, such as attributes describing discriminative object properties, requires time-consuming annotation by domain experts. We instead propose a method that relies on human gaze as auxiliary information, exploiting that even non-expert users have

  18. Ontogenetic effects on gazing behaviour: a case study of kennel dogs (Labrador Retrievers) in the impossible task paradigm.

    Science.gov (United States)

    D'Aniello, Biagio; Scandurra, Anna

    2016-05-01

    Life experiences and living conditions can influence the problem-solving strategies and the communicative abilities of dogs with humans. The goals of this study were to determine any behavioural differences between Labrador Retrievers living in a kennel and those living in a house as pets and to assess whether kennel dogs show preferences in social behaviours for their caretaker relative to a stranger when they are faced with an unsolvable task. Nine Labrador Retrievers living in a kennel from birth and ten Labrador Retrievers living in a family as pets were tested. The experimental procedure consisted of three "solvable" tasks in which the dogs could easily retrieve food from a container followed by an "unsolvable" task in which the container was hermetically locked. Dogs of both groups spent the same amount of time interacting with the experimental apparatus. Kennel dogs gazed towards people for less time and with higher latency than pet dogs; however, there were no significant preferences in gazing towards the stranger versus the caretaker in both groups. These findings demonstrated that kennel dogs are less prone to use human-directed gazing behaviour when they are faced with an unsolvable problem, taking the humans into account to solve a task less than do the pet dogs.

  19. Subjects and Objects of the Embodied Gaze: Abbas Kiarostami and the Real of the Individual Perspective

    Directory of Open Access Journals (Sweden)

    Gyenge Zsolt

    2016-12-01

    Full Text Available It is widely accepted that Abbas Kiarostami’s cinema revolves around the representation of the gaze. Many critics argue that he should be considered a late modernist who repeats the self-reflexive gestures of modernist European cinema decades after they were first introduced. The present paper will contradict this assertion by investigating the problematic of the Kiarostamian gaze and analyzing the perceptual side of the act of looking. I will argue that instead of focusing on the gaze of the spectator directed towards the filmic image, he exposes a gaze that is fully integrated into the reality to be captured on film. The second part of the paper will explain this by linking the concept of gaze to the Lacanian concept of the order of the Real. Finally, I will contextualize all this by discussing the Iranian director’s position between Eastern and Western traditions of representation.

  20. Age differences in conscious versus subconscious social perception: The influence of face age and valence on gaze following.

    OpenAIRE

    Bailey, P.E.; Slessor, G.; Rendell, P.G.; Bennetts, Rachel; Campbell, A.; Ruffman, T.

    2014-01-01

    Gaze following is the primary means of establishing joint attention with others and is subject to age-related decline. In addition, young but not older adults experience an own-age bias in gaze following. The current research assessed the effects of subconscious processing on these age-related differences. Participants responded to targets that were either congruent or incongruent with the direction of gaze displayed in supraliminal and subliminal images of young and older faces. These faces ...

  1. The Role of Global and Local Visual Information during Gaze-Cued Orienting of Attention.

    Science.gov (United States)

    Munsters, Nicolette M; van den Boomen, Carlijn; Hooge, Ignace T C; Kemner, Chantal

    2016-01-01

    Gaze direction is an important social communication tool. Global and local visual information are known to play specific roles in processing socially relevant information from a face. The current study investigated whether global visual information has a primary role during gaze-cued orienting of attention and, as such, may influence quality of interaction. Adults performed a gaze-cueing task in which a centrally presented face cued (valid or invalid) the location of a peripheral target through a gaze shift. We measured brain activity (electroencephalography) towards the cue and target and behavioral responses (manual and saccadic reaction times) towards the target. The faces contained global (i.e. lower spatial frequencies), local (i.e. higher spatial frequencies), or a selection of both global and local (i.e. mid-band spatial frequencies) visual information. We found a gaze cue-validity effect (i.e. valid versus invalid), but no interaction effects with spatial frequency content. Furthermore, behavioral responses towards the target were in all cue conditions slower when lower spatial frequencies were not present in the gaze cue. These results suggest that whereas gaze-cued orienting of attention can be driven by both global and local visual information, global visual information determines the speed of behavioral responses towards other entities appearing in the surrounding of gaze cue stimuli.

  2. Gaze-Based Controlling a Vehicle

    DEFF Research Database (Denmark)

    Mardanbeigi, Diako; Witzner Hansen, Dan

    ) as an example of a complex gaze-based task in environment. This paper discusses the possibilities and limitations of how gaze interaction can be performed for controlling vehicles not only using a remote gaze tracker but also in general challenging situations where the user and robot are mobile...... modality if gaze trackers are embedded into the head- mounted devices. The domain of gaze-based interactive applications increases dramatically as interaction is no longer constrained to 2D displays. This paper proposes a general framework for gaze-based controlling a non- stationary robot (vehicle...... and the movements may be governed by several degrees of freedom (e.g. flying). A case study is also introduced where the mobile gaze tracker is used for controlling a Roomba vacuum cleaner....

  3. Investigating social gaze as an action-perception online performance

    Directory of Open Access Journals (Sweden)

    Ouriel eGrynszpan

    2012-04-01

    Full Text Available In interpersonal interactions, linguistic information is complemented by non-linguistic information originating largely from facial expressions. The study of online face-to-face social interaction thus entails investigating the multimodal simultaneous processing of oral and visual percepts. Moreover, gaze in and of itself functions as a powerful communicative channel. In this respect, gaze should not be examined as a purely perceptive process but also as an active social performance. We designed a task involving multimodal deciphering of social information based on virtual characters, embedded in naturalistic backgrounds, who directly address the participant with non-literal speech and meaningful facial expressions. Eighteen adult participants were to interpret an equivocal sentence which could be disambiguated by examining the emotional expressions of the character speaking to them face-to-face. To examine self-control and self-awareness of gaze in this context, visual feedback is provided to the participant by a real-time gaze-contingent viewing window centered on the focal point, while the rest of the display is blurred. Eye-tracking data showed that the viewing window induced changes in gaze behaviour, notably longer visual fixations. Notwithstanding, only half the participants ascribed the window displacements to their eye movements. These results highlight the dissociation between non volitional gaze adaptation and self-ascription of agency. Such dissociation provides support for a two-step account of the sense of agency composed of pre-noetic monitoring mechanisms and reflexive processes. We comment upon these results, which illustrate the relevance of our method for studying online social cognition, especially concerning Autism Spectrum Disorders (ASD where poor pragmatic understanding of oral speech are considered linked to visual peculiarities that impede face exploration.

  4. Text Entry by Gazing and Smiling

    Directory of Open Access Journals (Sweden)

    Outi Tuisku

    2013-01-01

    Full Text Available Face Interface is a wearable prototype that combines the use of voluntary gaze direction and facial activations, for pointing and selecting objects on a computer screen, respectively. The aim was to investigate the functionality of the prototype for entering text. First, three on-screen keyboard layout designs were developed and tested (n=10 to find a layout that would be more suitable for text entry with the prototype than traditional QWERTY layout. The task was to enter one word ten times with each of the layouts by pointing letters with gaze and select them by smiling. Subjective ratings showed that a layout with large keys on the edge and small keys near the center of the keyboard was rated as the most enjoyable, clearest, and most functional. Second, using this layout, the aim of the second experiment (n=12 was to compare entering text with Face Interface to entering text with mouse. The results showed that text entry rate for Face Interface was 20 characters per minute (cpm and 27 cpm for the mouse. For Face Interface, keystrokes per character (KSPC value was 1.1 and minimum string distance (MSD error rate was 0.12. These values compare especially well with other similar techniques.

  5. Real-time estimation of horizontal gaze angle by saccade integration using in-ear electrooculography.

    Science.gov (United States)

    Hládek, Ľuboš; Porr, Bernd; Brimijoin, W Owen

    2018-01-01

    The manuscript proposes and evaluates a real-time algorithm for estimating eye gaze angle based solely on single-channel electrooculography (EOG), which can be obtained directly from the ear canal using conductive ear moulds. In contrast to conventional high-pass filtering, we used an algorithm that calculates absolute eye gaze angle via statistical analysis of detected saccades. The estimated eye positions of the new algorithm were still noisy. However, the performance in terms of Pearson product-moment correlation coefficients was significantly better than the conventional approach in some instances. The results suggest that in-ear EOG signals captured with conductive ear moulds could serve as a basis for light-weight and portable horizontal eye gaze angle estimation suitable for a broad range of applications. For instance, for hearing aids to steer the directivity of microphones in the direction of the user's eye gaze.

  6. Real-time estimation of horizontal gaze angle by saccade integration using in-ear electrooculography.

    Directory of Open Access Journals (Sweden)

    Ľuboš Hládek

    Full Text Available The manuscript proposes and evaluates a real-time algorithm for estimating eye gaze angle based solely on single-channel electrooculography (EOG, which can be obtained directly from the ear canal using conductive ear moulds. In contrast to conventional high-pass filtering, we used an algorithm that calculates absolute eye gaze angle via statistical analysis of detected saccades. The estimated eye positions of the new algorithm were still noisy. However, the performance in terms of Pearson product-moment correlation coefficients was significantly better than the conventional approach in some instances. The results suggest that in-ear EOG signals captured with conductive ear moulds could serve as a basis for light-weight and portable horizontal eye gaze angle estimation suitable for a broad range of applications. For instance, for hearing aids to steer the directivity of microphones in the direction of the user's eye gaze.

  7. There is more to gaze than meets the eye: How animals perceive the visual behaviour of others

    NARCIS (Netherlands)

    Goossens, B.M.A.

    2008-01-01

    Gaze following and the ability to understand that another individual sees something different from oneself are considered important components of human and animal social cognition. In animals, gaze following has been documented in various species, however, the underlying cognitive mechanisms and the

  8. Elevator Illusion and Gaze Direction in Hypergravity

    Science.gov (United States)

    Cohen, Malcolm M.; Hargens, Alan (Technical Monitor)

    1995-01-01

    A luminous visual target in a dark hypergravity (Gz greater than 1) environment appears to be elevated above its true physical position. This "elevator illusion" has been attributed to changes in oculomotor control caused by increased stimulation of the otolith organs. Data relating the magnitude of the illusion to the magnitude of the changes in oculomotor control have been lacking. The present study provides such data.

  9. Biasing moral decisions by exploiting the dynamics of eye gaze.

    Science.gov (United States)

    Pärnamets, Philip; Johansson, Petter; Hall, Lars; Balkenius, Christian; Spivey, Michael J; Richardson, Daniel C

    2015-03-31

    Eye gaze is a window onto cognitive processing in tasks such as spatial memory, linguistic processing, and decision making. We present evidence that information derived from eye gaze can be used to change the course of individuals' decisions, even when they are reasoning about high-level, moral issues. Previous studies have shown that when an experimenter actively controls what an individual sees the experimenter can affect simple decisions with alternatives of almost equal valence. Here we show that if an experimenter passively knows when individuals move their eyes the experimenter can change complex moral decisions. This causal effect is achieved by simply adjusting the timing of the decisions. We monitored participants' eye movements during a two-alternative forced-choice task with moral questions. One option was randomly predetermined as a target. At the moment participants had fixated the target option for a set amount of time we terminated their deliberation and prompted them to choose between the two alternatives. Although participants were unaware of this gaze-contingent manipulation, their choices were systematically biased toward the target option. We conclude that even abstract moral cognition is partly constituted by interactions with the immediate environment and is likely supported by gaze-dependent decision processes. By tracking the interplay between individuals, their sensorimotor systems, and the environment, we can influence the outcome of a decision without directly manipulating the content of the information available to them.

  10. Investigating the Link Between Radiologists Gaze, Diagnostic Decision, and Image Content

    Energy Technology Data Exchange (ETDEWEB)

    Tourassi, Georgia [ORNL; Voisin, Sophie [ORNL; Paquit, Vincent C [ORNL; Krupinski, Elizabeth [University of Arizona

    2013-01-01

    Objective: To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Methods: Gaze data and diagnostic decisions were collected from six radiologists who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Texture analysis was performed in mammographic regions that attracted radiologists attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. Results: By pooling the data from all radiologists machine learning produced highly accurate predictive models linking image content, gaze, cognition, and error. Merging radiologists gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the radiologists diagnostic errors while confirming 96.2% of their correct diagnoses. The radiologists individual errors could be adequately predicted by modeling the behavior of their peers. However, personalized tuning appears to be beneficial in many cases to capture more accurately individual behavior. Conclusions: Machine learning algorithms combining image features with radiologists gaze data and diagnostic decisions can be effectively developed to recognize cognitive and perceptual errors associated with the diagnostic interpretation of mammograms.

  11. Investigating the link between radiologists’ gaze, diagnostic decision, and image content

    Science.gov (United States)

    Tourassi, Georgia; Voisin, Sophie; Paquit, Vincent; Krupinski, Elizabeth

    2013-01-01

    Objective To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Methods Gaze data and diagnostic decisions were collected from three breast imaging radiologists and three radiology residents who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Image analysis was performed in mammographic regions that attracted radiologists’ attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. Results By pooling the data from all readers, machine learning produced highly accurate predictive models linking image content, gaze, and cognition. Potential linking of those with diagnostic error was also supported to some extent. Merging readers’ gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the readers’ diagnostic errors while confirming 97.3% of their correct diagnoses. The readers’ individual perceptual and cognitive behaviors could be adequately predicted by modeling the behavior of others. However, personalized tuning was in many cases beneficial for capturing more accurately individual behavior. Conclusions There is clearly an interaction between radiologists’ gaze, diagnostic decision, and image content which can be modeled with machine learning algorithms. PMID:23788627

  12. A closer look at the size of the gaze-liking effect: a preregistered replication.

    Science.gov (United States)

    Tipples, Jason; Pecchinenda, Anna

    2018-04-30

    This study is a direct replication of gaze-liking effect using the same design, stimuli and procedure. The gaze-liking effect describes the tendency for people to rate objects as more likeable when they have recently seen a person repeatedly gaze toward rather than away from the object. However, as subsequent studies show considerable variability in the size of this effect, we sampled a larger number of participants (N = 98) than the original study (N = 24) to gain a more precise estimate of the gaze-liking effect size. Our results indicate a much smaller standardised effect size (d z  = 0.02) than that of the original study (d z  = 0.94). Our smaller effect size was not due to general insensitivity to eye-gaze effects because the same sample showed a clear (d z  = 1.09) gaze-cuing effect - faster reaction times when eyes looked toward vs away from target objects. We discuss the implications of our findings for future studies wishing to study the gaze-liking effect.

  13. Eyes that bind us: Gaze leading induces an implicit sense of agency.

    Science.gov (United States)

    Stephenson, Lisa J; Edwards, S Gareth; Howard, Emma E; Bayliss, Andrew P

    2018-03-01

    Humans feel a sense of agency over the effects their motor system causes. This is the case for manual actions such as pushing buttons, kicking footballs, and all acts that affect the physical environment. We ask whether initiating joint attention - causing another person to follow our eye movement - can elicit an implicit sense of agency over this congruent gaze response. Eye movements themselves cannot directly affect the physical environment, but joint attention is an example of how eye movements can indirectly cause social outcomes. Here we show that leading the gaze of an on-screen face induces an underestimation of the temporal gap between action and consequence (Experiments 1 and 2). This underestimation effect, named 'temporal binding,' is thought to be a measure of an implicit sense of agency. Experiment 3 asked whether merely making an eye movement in a non-agentic, non-social context might also affect temporal estimation, and no reliable effects were detected, implying that inconsequential oculomotor acts do not reliably affect temporal estimations under these conditions. Together, these findings suggest that an implicit sense of agency is generated when initiating joint attention interactions. This is important for understanding how humans can efficiently detect and understand the social consequences of their actions. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Speaking and Listening with the Eyes: Gaze Signaling during Dyadic Interactions.

    Science.gov (United States)

    Ho, Simon; Foulsham, Tom; Kingstone, Alan

    2015-01-01

    Cognitive scientists have long been interested in the role that eye gaze plays in social interactions. Previous research suggests that gaze acts as a signaling mechanism and can be used to control turn-taking behaviour. However, early research on this topic employed methods of analysis that aggregated gaze information across an entire trial (or trials), which masks any temporal dynamics that may exist in social interactions. More recently, attempts have been made to understand the temporal characteristics of social gaze but little research has been conducted in a natural setting with two interacting participants. The present study combines a temporally sensitive analysis technique with modern eye tracking technology to 1) validate the overall results from earlier aggregated analyses and 2) provide insight into the specific moment-to-moment temporal characteristics of turn-taking behaviour in a natural setting. Dyads played two social guessing games (20 Questions and Heads Up) while their eyes were tracked. Our general results are in line with past aggregated data, and using cross-correlational analysis on the specific gaze and speech signals of both participants we found that 1) speakers end their turn with direct gaze at the listener and 2) the listener in turn begins to speak with averted gaze. Convergent with theoretical models of social interaction, our data suggest that eye gaze can be used to signal both the end and the beginning of a speaking turn during a social interaction. The present study offers insight into the temporal dynamics of live dyadic interactions and also provides a new method of analysis for eye gaze data when temporal relationships are of interest.

  15. Speaking and Listening with the Eyes: Gaze Signaling during Dyadic Interactions.

    Directory of Open Access Journals (Sweden)

    Simon Ho

    Full Text Available Cognitive scientists have long been interested in the role that eye gaze plays in social interactions. Previous research suggests that gaze acts as a signaling mechanism and can be used to control turn-taking behaviour. However, early research on this topic employed methods of analysis that aggregated gaze information across an entire trial (or trials, which masks any temporal dynamics that may exist in social interactions. More recently, attempts have been made to understand the temporal characteristics of social gaze but little research has been conducted in a natural setting with two interacting participants. The present study combines a temporally sensitive analysis technique with modern eye tracking technology to 1 validate the overall results from earlier aggregated analyses and 2 provide insight into the specific moment-to-moment temporal characteristics of turn-taking behaviour in a natural setting. Dyads played two social guessing games (20 Questions and Heads Up while their eyes were tracked. Our general results are in line with past aggregated data, and using cross-correlational analysis on the specific gaze and speech signals of both participants we found that 1 speakers end their turn with direct gaze at the listener and 2 the listener in turn begins to speak with averted gaze. Convergent with theoretical models of social interaction, our data suggest that eye gaze can be used to signal both the end and the beginning of a speaking turn during a social interaction. The present study offers insight into the temporal dynamics of live dyadic interactions and also provides a new method of analysis for eye gaze data when temporal relationships are of interest.

  16. Culture and Listeners' Gaze Responses to Stuttering

    Science.gov (United States)

    Zhang, Jianliang; Kalinowski, Joseph

    2012-01-01

    Background: It is frequently observed that listeners demonstrate gaze aversion to stuttering. This response may have profound social/communicative implications for both fluent and stuttering individuals. However, there is a lack of empirical examination of listeners' eye gaze responses to stuttering, and it is unclear whether cultural background…

  17. Adaptive gaze control for object detection

    NARCIS (Netherlands)

    De Croon, G.C.H.E.; Postma, E.O.; Van den Herik, H.J.

    2011-01-01

    We propose a novel gaze-control model for detecting objects in images. The model, named act-detect, uses the information from local image samples in order to shift its gaze towards object locations. The model constitutes two main contributions. The first contribution is that the model’s setup makes

  18. Reading the mind from eye gaze.

    NARCIS (Netherlands)

    Christoffels, I.; Young, A.W.; Owen, A.M.; Scott, S.K.; Keane, J.; Lawrence, A.D.

    2002-01-01

    S. Baron-Cohen (1997) has suggested that the interpretation of gaze plays an important role in a normal functioning theory of mind (ToM) system. Consistent with this suggestion, functional imaging research has shown that both ToM tasks and eye gaze processing engage a similar region of the posterior

  19. Gaze Cueing by Pareidolia Faces

    OpenAIRE

    Kohske Takahashi; Katsumi Watanabe

    2013-01-01

    Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cuei...

  20. Cerebellar inactivation impairs memory of learned prism gaze-reach calibrations.

    Science.gov (United States)

    Norris, Scott A; Hathaway, Emily N; Taylor, Jordan A; Thach, W Thomas

    2011-05-01

    Three monkeys performed a visually guided reach-touch task with and without laterally displacing prisms. The prisms offset the normally aligned gaze/reach and subsequent touch. Naive monkeys showed adaptation, such that on repeated prism trials the gaze-reach angle widened and touches hit nearer the target. On the first subsequent no-prism trial the monkeys exhibited an aftereffect, such that the widened gaze-reach angle persisted and touches missed the target in the direction opposite that of initial prism-induced error. After 20-30 days of training, monkeys showed long-term learning and storage of the prism gaze-reach calibration: they switched between prism and no-prism and touched the target on the first trials without adaptation or aftereffect. Injections of lidocaine into posterolateral cerebellar cortex or muscimol or lidocaine into dentate nucleus temporarily inactivated these structures. Immediately after injections into cortex or dentate, reaches were displaced in the direction of prism-displaced gaze, but no-prism reaches were relatively unimpaired. There was little or no adaptation on the day of injection. On days after injection, there was no adaptation and both prism and no-prism reaches were horizontally, and often vertically, displaced. A single permanent lesion (kainic acid) in the lateral dentate nucleus of one monkey immediately impaired only the learned prism gaze-reach calibration and in subsequent days disrupted both learning and performance. This effect persisted for the 18 days of observation, with little or no adaptation.

  1. The Gaze-Cueing Effect in the United States and Japan: Influence of Cultural Differences in Cognitive Strategies on Control of Attention

    Directory of Open Access Journals (Sweden)

    Saki Takao

    2018-01-01

    Full Text Available The direction of gaze automatically and exogenously guides visual spatial attention, a phenomenon termed as the gaze-cueing effect. Although this effect arises when the duration of stimulus onset asynchrony (SOA between a non-predictive gaze cue and the target is relatively long, no empirical research has examined the factors underlying this extended cueing effect. Two experiments compared the gaze-cueing effect at longer SOAs (700 ms in Japanese and American participants. Cross-cultural studies on cognition suggest that Westerners tend to use a context-independent analytical strategy to process visual environments, whereas Asians use a context-dependent holistic approach. We hypothesized that Japanese participants would not demonstrate the gaze-cueing effect at longer SOAs because they are more sensitive to contextual information, such as the knowledge that the direction of a gaze is not predictive. Furthermore, we hypothesized that American participants would demonstrate the gaze-cueing effect at the long SOAs because they tend to follow gaze direction whether it is predictive or not. In Experiment 1, American participants demonstrated the gaze-cueing effect at the long SOA, indicating that their attention was driven by the central non-predictive gaze direction regardless of the SOAs. In Experiment 2, Japanese participants demonstrated no gaze-cueing effect at the long SOA, suggesting that the Japanese participants exercised voluntary control of their attention, which inhibited the gaze-cueing effect with the long SOA. Our findings suggest that the control of visual spatial attention elicited by social stimuli systematically differs between American and Japanese individuals.

  2. The Gaze-Cueing Effect in the United States and Japan: Influence of Cultural Differences in Cognitive Strategies on Control of Attention.

    Science.gov (United States)

    Takao, Saki; Yamani, Yusuke; Ariga, Atsunori

    2017-01-01

    The direction of gaze automatically and exogenously guides visual spatial attention, a phenomenon termed as the gaze-cueing effect . Although this effect arises when the duration of stimulus onset asynchrony (SOA) between a non-predictive gaze cue and the target is relatively long, no empirical research has examined the factors underlying this extended cueing effect. Two experiments compared the gaze-cueing effect at longer SOAs (700 ms) in Japanese and American participants. Cross-cultural studies on cognition suggest that Westerners tend to use a context-independent analytical strategy to process visual environments, whereas Asians use a context-dependent holistic approach. We hypothesized that Japanese participants would not demonstrate the gaze-cueing effect at longer SOAs because they are more sensitive to contextual information, such as the knowledge that the direction of a gaze is not predictive. Furthermore, we hypothesized that American participants would demonstrate the gaze-cueing effect at the long SOAs because they tend to follow gaze direction whether it is predictive or not. In Experiment 1, American participants demonstrated the gaze-cueing effect at the long SOA, indicating that their attention was driven by the central non-predictive gaze direction regardless of the SOAs. In Experiment 2, Japanese participants demonstrated no gaze-cueing effect at the long SOA, suggesting that the Japanese participants exercised voluntary control of their attention, which inhibited the gaze-cueing effect with the long SOA. Our findings suggest that the control of visual spatial attention elicited by social stimuli systematically differs between American and Japanese individuals.

  3. Age differences in conscious versus subconscious social perception: the influence of face age and valence on gaze following.

    Science.gov (United States)

    Bailey, Phoebe E; Slessor, Gillian; Rendell, Peter G; Bennetts, Rachel J; Campbell, Anna; Ruffman, Ted

    2014-09-01

    Gaze following is the primary means of establishing joint attention with others and is subject to age-related decline. In addition, young but not older adults experience an own-age bias in gaze following. The current research assessed the effects of subconscious processing on these age-related differences. Participants responded to targets that were either congruent or incongruent with the direction of gaze displayed in supraliminal and subliminal images of young and older faces. These faces displayed either neutral (Study 1) or happy and fearful (Study 2) expressions. In Studies 1 and 2, both age groups demonstrated gaze-directed attention by responding faster to targets that were congruent as opposed to incongruent with gaze-cues. In Study 1, subliminal stimuli did not attenuate the age-related decline in gaze-cuing, but did result in an own-age bias among older participants. In Study 2, gaze-cuing was reduced for older relative to young adults in response to supraliminal stimuli, and this could not be attributed to reduced visual acuity or age group differences in the perceived emotional intensity of the gaze-cue faces. Moreover, there were no age differences in gaze-cuing when responding to subliminal faces that were emotionally arousing. In addition, older adults demonstrated an own-age bias for both conscious and subconscious gaze-cuing when faces expressed happiness but not fear. We discuss growing evidence for age-related preservation of subconscious relative to conscious social perception, as well as an interaction between face age and valence in social perception. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  4. Real-time gaze estimation via pupil center tracking

    Directory of Open Access Journals (Sweden)

    Cazzato Dario

    2018-02-01

    Full Text Available Automatic gaze estimation not based on commercial and expensive eye tracking hardware solutions can enable several applications in the fields of human computer interaction (HCI and human behavior analysis. It is therefore not surprising that several related techniques and methods have been investigated in recent years. However, very few camera-based systems proposed in the literature are both real-time and robust. In this work, we propose a real-time user-calibration-free gaze estimation system that does not need person-dependent calibration, can deal with illumination changes and head pose variations, and can work with a wide range of distances from the camera. Our solution is based on a 3-D appearance-based method that processes the images from a built-in laptop camera. Real-time performance is obtained by combining head pose information with geometrical eye features to train a machine learning algorithm. Our method has been validated on a data set of images of users in natural environments, and shows promising results. The possibility of a real-time implementation, combined with the good quality of gaze tracking, make this system suitable for various HCI applications.

  5. Gazes

    DEFF Research Database (Denmark)

    Khawaja, Iram

    2015-01-01

    of passing. The analysis of the young Muslim men and women’s narratives points towards the particular embodied, intersectional and local possibilities for becoming and being visible as a legitimate Muslim subject in a society fraught with stereotypical and often negative images and discourses on Islam...

  6. Orienting of attention via observed eye gaze is head-centred.

    Science.gov (United States)

    Bayliss, Andrew P; di Pellegrino, Giuseppe; Tipper, Steven P

    2004-11-01

    Observing averted eye gaze results in the automatic allocation of attention to the gazed-at location. The role of the orientation of the face that produces the gaze cue was investigated. The eyes in the face could look left or right in a head-centred frame, but the face itself could be oriented 90 degrees clockwise or anticlockwise such that the eyes were gazing up or down. Significant cueing effects to targets presented to the left or right of the screen were found in these head orientation conditions. This suggests that attention was directed to the side to which the eyes would have been looking towards, had the face been presented upright. This finding provides evidence that head orientation can affect gaze following, even when the head orientation alone is not a social cue. It also shows that the mechanism responsible for the allocation of attention following a gaze cue can be influenced by intrinsic object-based (i.e. head-centred) properties of the task-irrelevant cue.

  7. Mobile gaze input system for pervasive interaction

    DEFF Research Database (Denmark)

    2017-01-01

    feedback to the user in response to the received command input. The unit provides feedback to the user on how to position the mobile unit in front of his eyes. The gaze tracking unit interacts with one or more controlled devices via wireless or wired communications. Example devices include a lock......, a thermostat, a light or a TV. The connection between the gaze tracking unit may be temporary or longer-lasting. The gaze tracking unit may detect features of the eye that provide information about the identity of the user....

  8. Wrist-worn pervasive gaze interaction

    DEFF Research Database (Denmark)

    Hansen, John Paulin; Lund, Haakon; Biermann, Florian

    2016-01-01

    This paper addresses gaze interaction for smart home control, conducted from a wrist-worn unit. First we asked ten people to enact the gaze movements they would propose for e.g. opening a door or adjusting the room temperature. On basis of their suggestions we built and tested different versions...... selection. Their subjective evaluations were positive with regard to the speed of the interaction. We conclude that gaze gesture input seems feasible for fast and brief remote control of smart home technology provided that robustness of tracking is improved....

  9. Gaze Cueing by Pareidolia Faces

    Directory of Open Access Journals (Sweden)

    Kohske Takahashi

    2013-12-01

    Full Text Available Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon. While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cueing effect was comparable between the face-like objects and a cartoon face. However, the cueing effect was eliminated when the observer did not perceive the objects as faces. These results demonstrated that pareidolia faces do more than give the impression of the presence of faces; indeed, they trigger an additional face-specific attentional process.

  10. Gaze cueing by pareidolia faces.

    Science.gov (United States)

    Takahashi, Kohske; Watanabe, Katsumi

    2013-01-01

    Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cueing effect was comparable between the face-like objects and a cartoon face. However, the cueing effect was eliminated when the observer did not perceive the objects as faces. These results demonstrated that pareidolia faces do more than give the impression of the presence of faces; indeed, they trigger an additional face-specific attentional process.

  11. Eye and head movements shape gaze shifts in Indian peafowl.

    Science.gov (United States)

    Yorzinski, Jessica L; Patricelli, Gail L; Platt, Michael L; Land, Michael F

    2015-12-01

    Animals selectively direct their visual attention toward relevant aspects of their environments. They can shift their attention using a combination of eye, head and body movements. While we have a growing understanding of eye and head movements in mammals, we know little about these processes in birds. We therefore measured the eye and head movements of freely behaving Indian peafowl (Pavo cristatus) using a telemetric eye-tracker. Both eye and head movements contributed to gaze changes in peafowl. When gaze shifts were smaller, eye movements played a larger role than when gaze shifts were larger. The duration and velocity of eye and head movements were positively related to the size of the eye and head movements, respectively. In addition, the coordination of eye and head movements in peafowl differed from that in mammals; peafowl exhibited a near-absence of the vestibulo-ocular reflex, which may partly result from the peafowl's ability to move their heads as quickly as their eyes. © 2015. Published by The Company of Biologists Ltd.

  12. Does the 'P300' speller depend on eye gaze?

    Science.gov (United States)

    Brunner, P.; Joshi, S.; Briskin, S.; Wolpaw, J. R.; Bischof, H.; Schalk, G.

    2010-10-01

    Many people affected by debilitating neuromuscular disorders such as amyotrophic lateral sclerosis, brainstem stroke or spinal cord injury are impaired in their ability to, or are even unable to, communicate. A brain-computer interface (BCI) uses brain signals, rather than muscles, to re-establish communication with the outside world. One particular BCI approach is the so-called 'P300 matrix speller' that was first described by Farwell and Donchin (1988 Electroencephalogr. Clin. Neurophysiol. 70 510-23). It has been widely assumed that this method does not depend on the ability to focus on the desired character, because it was thought that it relies primarily on the P300-evoked potential and minimally, if at all, on other EEG features such as the visual-evoked potential (VEP). This issue is highly relevant for the clinical application of this BCI method, because eye movements may be impaired or lost in the relevant user population. This study investigated the extent to which the performance in a 'P300' speller BCI depends on eye gaze. We evaluated the performance of 17 healthy subjects using a 'P300' matrix speller under two conditions. Under one condition ('letter'), the subjects focused their eye gaze on the intended letter, while under the second condition ('center'), the subjects focused their eye gaze on a fixation cross that was located in the center of the matrix. The results show that the performance of the 'P300' matrix speller in normal subjects depends in considerable measure on gaze direction. They thereby disprove a widespread assumption in BCI research, and suggest that this BCI might function more effectively for people who retain some eye-movement control. The applicability of these findings to people with severe neuromuscular disabilities (particularly in eye-movements) remains to be determined.

  13. Effects of flow gradients on directional radiation of human voice.

    Science.gov (United States)

    Pulkki, Ville; Lähivaara, Timo; Huhtakallio, Ilkka

    2018-02-01

    In voice communication in windy outdoor conditions, complex velocity gradients appear in the flow field around the source, the receiver, and also in the atmosphere. It is commonly known that voice emanates stronger towards the downstream direction when compared with the upstream direction. In literature, the atmospheric effects are used to explain the stronger emanation in the downstream direction. This work shows that the wind also has an effect to the directivity of voice also favouring the downstream direction. The effect is addressed by measurements and simulations. Laboratory measurements are conducted by using a large pendulum with a loudspeaker mimicking the human head, whereas practical measurements utilizing the human voice are realized by placing a subject through the roof window of a moving car. The measurements and a simulation indicate congruent results in the speech frequency range: When the source faces the downstream direction, stronger radiation coinciding with the wind direction is observed, and when it faces the upstream direction, radiation is not affected notably. The simulated flow gradients show a wake region in the downstream direction, and the simulated acoustic field in the flow show that the region causes a wave-guide effect focusing the sound in the direction.

  14. Latvijas Gaze buyback likely to flop

    Index Scriptorium Estoniae

    2003-01-01

    Veerandi Läti gaasifirma Latvijas Gaze omanik Itera kavatseb lähiajal lõpule viia üheksa protsendi Läti firma aktsiate müügi ettevõttele Gazprom. Gazprom'i kontrolli all on praegu 25 protsenti, Ruhrgas'il 28,66 ning E.ON Energie AG-l 18,06 protsenti Latvijas Gaze aktsiatest

  15. EDITORIAL: Special section on gaze-independent brain-computer interfaces Special section on gaze-independent brain-computer interfaces

    Science.gov (United States)

    Treder, Matthias S.

    2012-08-01

    Restoring the ability to communicate and interact with the environment in patients with severe motor disabilities is a vision that has been the main catalyst of early brain-computer interface (BCI) research. The past decade has brought a diversification of the field. BCIs have been examined as a tool for motor rehabilitation and their benefit in non-medical applications such as mental-state monitoring for improved human-computer interaction and gaming has been confirmed. At the same time, the weaknesses of some approaches have been pointed out. One of these weaknesses is gaze-dependence, that is, the requirement that the user of a BCI system voluntarily directs his or her eye gaze towards a visual target in order to efficiently operate a BCI. This not only contradicts the main doctrine of BCI research, namely that BCIs should be independent of muscle activity, but it can also limit its real-world applicability both in clinical and non-medical settings. It is only in a scenario devoid of any motor activity that a BCI solution is without alternative. Gaze-dependencies have surfaced at two different points in the BCI loop. Firstly, a BCI that relies on visual stimulation may require users to fixate on the target location. Secondly, feedback is often presented visually, which implies that the user may have to move his or her eyes in order to perceive the feedback. This special section was borne out of a BCI workshop on gaze-independent BCIs held at the 2011 Society for Applied Neurosciences (SAN) Conference and has then been extended with additional contributions from other research groups. It compiles experimental and methodological work that aims toward gaze-independent communication and mental-state monitoring. Riccio et al review the current state-of-the-art in research on gaze-independent BCIs [1]. Van der Waal et al present a tactile speller that builds on the stimulation of the fingers of the right and left hand [2]. H¨ohne et al analyze the ergonomic aspects

  16. Radiologically defining horizontal gaze using EOS imaging-a prospective study of healthy subjects and a retrospective audit.

    Science.gov (United States)

    Hey, Hwee Weng Dennis; Tan, Kimberly-Anne; Ho, Vivienne Chien-Lin; Azhar, Syifa Bte; Lim, Joel-Louis; Liu, Gabriel Ka-Po; Wong, Hee-Kit

    2018-06-01

    As sagittal alignment of the cervical spine is important for maintaining horizontal gaze, it is important to determine the former for surgical correction. However, horizontal gaze remains poorly-defined from a radiological point of view. The objective of this study was to establish radiological criteria to define horizontal gaze. This study was conducted at a tertiary health-care institution over a 1-month period. A prospective cohort of healthy patients was used to determine the best radiological criteria for defining horizontal gaze. A retrospective cohort of patients without rigid spinal deformities was used to audit the incidence of horizontal gaze. Two categories of radiological parameters for determining horizontal gaze were tested: (1) the vertical offset distances of key identifiable structures from the horizontal gaze axis and (2) imaginary lines convergent with the horizontal gaze axis. Sixty-seven healthy subjects underwent whole-body EOS radiographs taken in a directed standing posture. Horizontal gaze was radiologically defined using each parameter, as represented by their means, 95% confidence intervals (CIs), and associated 2 standard deviations (SDs). Subsequently, applying the radiological criteria, we conducted a retrospective audit of such radiographs (before the implementation of a strict radioimaging standardization). The mean age of our prospective cohort was 46.8 years, whereas that of our retrospective cohort was 37.2 years. Gender was evenly distributed across both cohorts. The four parameters with the lowest 95% CI and 2 SD were the distance offsets of the midpoint of the hard palate (A) and the base of the sella turcica (B), the horizontal convergents formed by the tangential line to the hard palate (C), and the line joining the center of the orbital orifice with the internal occipital protuberance (D). In the prospective cohort, good sensitivity (>98%) was attained when two or more parameters were used. Audit using Criterion B

  17. Direct evidence of milk consumption from ancient human dental calculus

    DEFF Research Database (Denmark)

    Warinner, C.; Hendy, J.; Speller, C.

    2014-01-01

    directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG...... is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up...

  18. Evidence of directional and stabilizing selection in contemporary humans.

    Science.gov (United States)

    Sanjak, Jaleal S; Sidorenko, Julia; Robinson, Matthew R; Thornton, Kevin R; Visscher, Peter M

    2018-01-02

    Modern molecular genetic datasets, primarily collected to study the biology of human health and disease, can be used to directly measure the action of natural selection and reveal important features of contemporary human evolution. Here we leverage the UK Biobank data to test for the presence of linear and nonlinear natural selection in a contemporary population of the United Kingdom. We obtain phenotypic and genetic evidence consistent with the action of linear/directional selection. Phenotypic evidence suggests that stabilizing selection, which acts to reduce variance in the population without necessarily modifying the population mean, is widespread and relatively weak in comparison with estimates from other species.

  19. Exploiting Three-Dimensional Gaze Tracking for Action Recognition During Bimanual Manipulation to Enhance Human–Robot Collaboration

    Directory of Open Access Journals (Sweden)

    Alireza Haji Fathaliyan

    2018-04-01

    Full Text Available Human–robot collaboration could be advanced by facilitating the intuitive, gaze-based control of robots, and enabling robots to recognize human actions, infer human intent, and plan actions that support human goals. Traditionally, gaze tracking approaches to action recognition have relied upon computer vision-based analyses of two-dimensional egocentric camera videos. The objective of this study was to identify useful features that can be extracted from three-dimensional (3D gaze behavior and used as inputs to machine learning algorithms for human action recognition. We investigated human gaze behavior and gaze–object interactions in 3D during the performance of a bimanual, instrumental activity of daily living: the preparation of a powdered drink. A marker-based motion capture system and binocular eye tracker were used to reconstruct 3D gaze vectors and their intersection with 3D point clouds of objects being manipulated. Statistical analyses of gaze fixation duration and saccade size suggested that some actions (pouring and stirring may require more visual attention than other actions (reach, pick up, set down, and move. 3D gaze saliency maps, generated with high spatial resolution for six subtasks, appeared to encode action-relevant information. The “gaze object sequence” was used to capture information about the identity of objects in concert with the temporal sequence in which the objects were visually regarded. Dynamic time warping barycentric averaging was used to create a population-based set of characteristic gaze object sequences that accounted for intra- and inter-subject variability. The gaze object sequence was used to demonstrate the feasibility of a simple action recognition algorithm that utilized a dynamic time warping Euclidean distance metric. Averaged over the six subtasks, the action recognition algorithm yielded an accuracy of 96.4%, precision of 89.5%, and recall of 89.2%. This level of performance suggests that

  20. Right hemispheric dominance and interhemispheric cooperation in gaze-triggered reflexive shift of attention.

    Science.gov (United States)

    Okada, Takashi; Sato, Wataru; Kubota, Yasutaka; Toichi, Motomi; Murai, Toshiya

    2012-03-01

    The neural substrate for the processing of gaze remains unknown. The aim of the present study was to clarify which hemisphere dominantly processes and whether bilateral hemispheres cooperate with each other in gaze-triggered reflexive shift of attention. Twenty-eight normal subjects were tested. The non-predictive gaze cues were presented either in unilateral or bilateral visual fields. The subjects localized the target as soon as possible. Reaction times (RT) were shorter when gaze-cues were congruent toward than away from targets, whichever visual field they were presented in. RT were shorter in left than right visual field presentations. RT in mono-directional bilateral presentations were shorter than both of those in left and right presentations. When bi-directional bilateral cues were presented, RT were faster when valid cues were presented in the left than right visual fields. The right hemisphere appears to be dominant, and there is interhemispheric cooperation in gaze-triggered reflexive shift of attention. © 2012 The Authors. Psychiatry and Clinical Neurosciences © 2012 Japanese Society of Psychiatry and Neurology.

  1. Structural behavior of human lumbar intervertebral disc under direct shear.

    Science.gov (United States)

    Schmidt, Hendrik; Häussler, Kim; Wilke, Hans-Joachim; Wolfram, Uwe

    2015-03-18

    The intervertebral disc (IVD) is a complex, flexible joint between adjacent vertebral bodies that provides load transmission while permitting movements of the spinal column. Finite element models can be used to help clarify why and how IVDs fail or degenerate. To do so, it is of importance to validate those models against controllable experiments. Due to missing experimental data, shear properties are not used thus far in validating finite element models. This study aimed to investigate the structural shear properties of human lumbar IVDs in posteroanterior (PA) and laterolateral (LL) loading directions. Fourteen lumbar IVDs (median age: 49 years) underwent direct shear in PA and LL loading directions. A custom-build shear device was used in combination with a materials testing machine to load the specimens until failure. Shear stiffness, ultimate shear force and displacement, and work to failure were determined. Each specimen was tested until complete or partial disruption. Median stiffness in PA direction was 490 N/mm and in LL direction 568 N/mm. Median ultimate shear force in the PA direction was 2,877 N and in the LL direction 3,199 N. Work to failure was 12 Nm in the PA and 9 Nm in the LL direction. This study was an experiment to subject IVDs to direct shear. The results could help us to understand the structure and function of IVDs with regard to mechanical spinal stability, and they can be used to validate finite element models of the IVD.

  2. Objective eye-gaze behaviour during face-to-face communication with proficient alaryngeal speakers: a preliminary study.

    Science.gov (United States)

    Evitts, Paul; Gallop, Robert

    2011-01-01

    There is a large body of research demonstrating the impact of visual information on speaker intelligibility in both normal and disordered speaker populations. However, there is minimal information on which specific visual features listeners find salient during conversational discourse. To investigate listeners' eye-gaze behaviour during face-to-face conversation with normal, laryngeal and proficient alaryngeal speakers. Sixty participants individually participated in a 10-min conversation with one of four speakers (typical laryngeal, tracheoesophageal, oesophageal, electrolaryngeal; 15 participants randomly assigned to one mode of speech). All speakers were > 85% intelligible and were judged to be 'proficient' by two certified speech-language pathologists. Participants were fitted with a head-mounted eye-gaze tracking device (Mobile Eye, ASL) that calculated the region of interest and mean duration of eye-gaze. Self-reported gaze behaviour was also obtained following the conversation using a 10 cm visual analogue scale. While listening, participants viewed the lower facial region of the oesophageal speaker more than the normal or tracheoesophageal speaker. Results of non-hierarchical cluster analyses showed that while listening, the pattern of eye-gaze was predominantly directed at the lower face of the oesophageal and electrolaryngeal speaker and more evenly dispersed among the background, lower face, and eyes of the normal and tracheoesophageal speakers. Finally, results show a low correlation between self-reported eye-gaze behaviour and objective regions of interest data. Overall, results suggest similar eye-gaze behaviour when healthy controls converse with normal and tracheoesophageal speakers and that participants had significantly different eye-gaze patterns when conversing with an oesophageal speaker. Results are discussed in terms of existing eye-gaze data and its potential implications on auditory-visual speech perception. © 2011 Royal College of Speech

  3. Visual Foraging With Fingers and Eye Gaze

    Directory of Open Access Journals (Sweden)

    Ómar I. Jóhannesson

    2016-03-01

    Full Text Available A popular model of the function of selective visual attention involves search where a single target is to be found among distractors. For many scenarios, a more realistic model involves search for multiple targets of various types, since natural tasks typically do not involve a single target. Here we present results from a novel multiple-target foraging paradigm. We compare finger foraging where observers cancel a set of predesignated targets by tapping them, to gaze foraging where observers cancel items by fixating them for 100 ms. During finger foraging, for most observers, there was a large difference between foraging based on a single feature, where observers switch easily between target types, and foraging based on a conjunction of features where observers tended to stick to one target type. The pattern was notably different during gaze foraging where these condition differences were smaller. Two conclusions follow: (a The fact that a sizeable number of observers (in particular during gaze foraging had little trouble switching between different target types raises challenges for many prominent theoretical accounts of visual attention and working memory. (b While caveats must be noted for the comparison of gaze and finger foraging, the results suggest that selection mechanisms for gaze and pointing have different operational constraints.

  4. Domestic dogs and puppies can use human voice direction referentially.

    Science.gov (United States)

    Rossano, Federico; Nitzschner, Marie; Tomasello, Michael

    2014-06-22

    Domestic dogs are particularly skilled at using human visual signals to locate hidden food. This is, to our knowledge, the first series of studies that investigates the ability of dogs to use only auditory communicative acts to locate hidden food. In a first study, from behind a barrier, a human expressed excitement towards a baited box on either the right or left side, while sitting closer to the unbaited box. Dogs were successful in following the human's voice direction and locating the food. In the two following control studies, we excluded the possibility that dogs could locate the box containing food just by relying on smell, and we showed that they would interpret a human's voice direction in a referential manner only when they could locate a possible referent (i.e. one of the boxes) in the environment. Finally, in a fourth study, we tested 8-14-week-old puppies in the main experimental test and found that those with a reasonable amount of human experience performed overall even better than the adult dogs. These results suggest that domestic dogs' skills in comprehending human communication are not based on visual cues alone, but are instead multi-modal and highly flexible. Moreover, the similarity between young and adult dogs' performances has important implications for the domestication hypothesis.

  5. Intranasal Oxytocin Treatment Increases Eye-Gaze Behavior toward the Owner in Ancient Japanese Dog Breeds

    Directory of Open Access Journals (Sweden)

    Miho Nagasawa

    2017-09-01

    Full Text Available Dogs acquired unique cognitive abilities during domestication, which is thought to have contributed to the formation of the human-dog bond. In European breeds, but not in wolves, a dog’s gazing behavior plays an important role in affiliative interactions with humans and stimulates oxytocin secretion in both humans and dogs, which suggests that this interspecies oxytocin and gaze-mediated bonding was also acquired during domestication. In this study, we investigated whether Japanese breeds, which are classified as ancient breeds and are relatively close to wolves genetically, establish a bond with their owners through gazing behavior. The subject dogs were treated with either oxytocin or saline before the starting of the behavioral testing. We also evaluated physiological changes in the owners during mutual gazing by analyzing their heart rate variability (HRV and subsequent urinary oxytocin levels in both dogs and their owners. We found that oxytocin treatment enhanced the gazing behavior of Japanese dogs and increased their owners’ urinary oxytocin levels, as was seen with European breeds; however, the measured durations of skin contact and proximity to their owners were relatively low. In the owners’ HRV readings, inter-beat (R-R intervals (RRI, the standard deviation of normal to normal inter-beat (R-R intervals (SDNN, and the root mean square of successive heartbeat interval differences (RMSSD were lower when the dogs were treated with oxytocin compared with saline. Furthermore, the owners of female dogs showed lower SDNN than the owners of male dogs. These results suggest that the owners of female Japanese dogs exhibit more tension during interactions, and apart from gazing behavior, the dogs may show sex differences in their interactions with humans as well. They also suggest that Japanese dogs use eye-gazing as an attachment behavior toward humans similar to European breeds; however, there is a disparity between the dog sexes when

  6. Direct dating of Early Upper Palaeolithic human remains from Mladec.

    Science.gov (United States)

    Wild, Eva M; Teschler-Nicola, Maria; Kutschera, Walter; Steier, Peter; Trinkaus, Erik; Wanek, Wolfgang

    2005-05-19

    The human fossil assemblage from the Mladec Caves in Moravia (Czech Republic) has been considered to derive from a middle or later phase of the Central European Aurignacian period on the basis of archaeological remains (a few stone artefacts and organic items such as bone points, awls, perforated teeth), despite questions of association between the human fossils and the archaeological materials and concerning the chronological implications of the limited archaeological remains. The morphological variability in the human assemblage, the presence of apparently archaic features in some specimens, and the assumed early date of the remains have made this fossil assemblage pivotal in assessments of modern human emergence within Europe. We present here the first successful direct accelerator mass spectrometry radiocarbon dating of five representative human fossils from the site. We selected sample materials from teeth and from one bone for 14C dating. The four tooth samples yielded uncalibrated ages of approximately 31,000 14C years before present, and the bone sample (an ulna) provided an uncertain more-recent age. These data are sufficient to confirm that the Mladec human assemblage is the oldest cranial, dental and postcranial assemblage of early modern humans in Europe and is therefore central to discussions of modern human emergence in the northwestern Old World and the fate of the Neanderthals.

  7. Acute oxytocin improves memory and gaze following in male but not female nursery-reared infant macaques.

    Science.gov (United States)

    Simpson, Elizabeth A; Paukner, Annika; Sclafani, Valentina; Kaburu, Stefano S K; Suomi, Stephen J; Ferrari, Pier F

    2017-02-01

    Exogenous oxytocin administration is widely reported to improve social cognition in human and nonhuman primate adults. Risk factors of impaired social cognition, however, emerge in infancy. Early interventions-when plasticity is greatest-are critical to reverse negative outcomes. We tested the hypothesis that oxytocin may exert similar positive effects on infant social cognition, as in adults. To test this idea, we assessed the effectiveness of acute, aerosolized oxytocin on two foundational social cognitive skills: working memory (i.e., ability to briefly hold and process information) and social gaze (i.e., tracking the direction of others' gaze) in 1-month-old nursery-reared macaque monkeys (Macaca mulatta). We did not predict sex differences, but we included sex as a factor in our analyses to test whether our effects would be generalizable across both males and females. In a double-blind, placebo-controlled design, we found that females were more socially skilled at baseline compared to males, and that oxytocin improved working memory and gaze following, but only in males. These sex differences, while unexpected, may be due to interactions with gonadal steroids and may be relevant to sexually dimorphic disorders of social cognition, such as male-biased autism spectrum disorder, for which oxytocin has been proposed as a potential treatment. In sum, we report the first evidence that oxytocin may influence primate infant cognitive abilities. Moreover, these behavioral effects appear sexually dimorphic, highlighting the importance of considering sex differences. Oxytocin effects observed in one sex may not be generalizable to the other sex.

  8. Altered attentional and perceptual processes as indexed by N170 during gaze perception in schizophrenia: Relationship with perceived threat and paranoid delusions.

    Science.gov (United States)

    Tso, Ivy F; Calwas, Anita M; Chun, Jinsoo; Mueller, Savanna A; Taylor, Stephan F; Deldin, Patricia J

    2015-08-01

    Using gaze information to orient attention and guide behavior is critical to social adaptation. Previous studies have suggested that abnormal gaze perception in schizophrenia (SCZ) may originate in abnormal early attentional and perceptual processes and may be related to paranoid symptoms. Using event-related brain potentials (ERPs), this study investigated altered early attentional and perceptual processes during gaze perception and their relationship to paranoid delusions in SCZ. Twenty-eight individuals with SCZ or schizoaffective disorder and 32 demographically matched healthy controls (HCs) completed a gaze-discrimination task with face stimuli varying in gaze direction (direct, averted), head orientation (forward, deviated), and emotion (neutral, fearful). ERPs were recorded during the task. Participants rated experienced threat from each face after the task. Participants with SCZ were as accurate as, though slower than, HCs on the task. Participants with SCZ displayed enlarged N170 responses over the left hemisphere to averted gaze presented in fearful relative to neutral faces, indicating a heightened encoding sensitivity to faces signaling external threat. This abnormality was correlated with increased perceived threat and paranoid delusions. Participants with SCZ also showed a reduction of N170 modulation by head orientation (normally increased amplitude to deviated faces relative to forward faces), suggesting less integration of contextual cues of head orientation in gaze perception. The psychophysiological deviations observed during gaze discrimination in SCZ underscore the role of early attentional and perceptual abnormalities in social information processing and paranoid symptoms of SCZ. (c) 2015 APA, all rights reserved).

  9. Gaze Estimation for Off-Angle Iris Recognition Based on the Biometric Eye Model

    Energy Technology Data Exchange (ETDEWEB)

    Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

    2013-01-01

    Iris recognition is among the highest accuracy biometrics. However, its accuracy relies on controlled high quality capture data and is negatively affected by several factors such as angle, occlusion, and dilation. Non-ideal iris recognition is a new research focus in biometrics. In this paper, we present a gaze estimation method designed for use in an off-angle iris recognition framework based on the ANONYMIZED biometric eye model. Gaze estimation is an important prerequisite step to correct an off-angle iris images. To achieve the accurate frontal reconstruction of an off-angle iris image, we first need to estimate the eye gaze direction from elliptical features of an iris image. Typically additional information such as well-controlled light sources, head mounted equipment, and multiple cameras are not available. Our approach utilizes only the iris and pupil boundary segmentation allowing it to be applicable to all iris capture hardware. We compare the boundaries with a look-up-table generated by using our biologically inspired biometric eye model and find the closest feature point in the look-up-table to estimate the gaze. Based on the results from real images, the proposed method shows effectiveness in gaze estimation accuracy for our biometric eye model with an average error of approximately 3.5 degrees over a 50 degree range.

  10. Predictive Gaze Cues and Personality Judgments: Should Eye Trust You?

    OpenAIRE

    Bayliss, Andrew P.; Tipper, Steven P.

    2006-01-01

    Although following another person's gaze is essential in fluent social interactions, the reflexive nature of this gaze-cuing effect means that gaze can be used to deceive. In a gaze-cuing procedure, participants were presented with several faces that looked to the left or right. Some faces always looked to the target (predictive-valid), some never looked to the target (predictive-invalid), and others looked toward and away from the target in equal proportions (nonpredictive). The standard gaz...

  11. Intermediate view synthesis for eye-gazing

    Science.gov (United States)

    Baek, Eu-Ttuem; Ho, Yo-Sung

    2015-01-01

    Nonverbal communication, also known as body language, is an important form of communication. Nonverbal behaviors such as posture, eye contact, and gestures send strong messages. In regard to nonverbal communication, eye contact is one of the most important forms that an individual can use. However, lack of eye contact occurs when we use video conferencing system. The disparity between locations of the eyes and a camera gets in the way of eye contact. The lock of eye gazing can give unapproachable and unpleasant feeling. In this paper, we proposed an eye gazing correction for video conferencing. We use two cameras installed at the top and the bottom of the television. The captured two images are rendered with 2D warping at virtual position. We implement view morphing to the detected face, and synthesize the face and the warped image. Experimental results verify that the proposed system is effective in generating natural gaze-corrected images.

  12. Gaze stabilization in chronic vestibular-loss and in cerebellar ataxia: interactions of feedforward and sensory feedback mechanisms.

    Science.gov (United States)

    Sağlam, M; Lehnen, N

    2014-01-01

    During gaze shifts, humans can use visual, vestibular, and proprioceptive feedback, as well as feedforward mechanisms, for stabilization against active and passive head movements. The contributions of feedforward and sensory feedback control, and the role of the cerebellum, are still under debate. To quantify these contributions, we increased the head moment of inertia in three groups (ten healthy, five chronic vestibular-loss and nine cerebellar-ataxia patients) while they performed large gaze shifts to flashed targets in darkness. This induces undesired head oscillations. Consequently, both active (desired) and passive (undesired) head movements had to be compensated for to stabilize gaze. All groups compensated for active and passive head movements, vestibular-loss patients less than the other groups (P feedforward mechanisms substantially contribute to gaze stabilization. Proprioception alone is not sufficient (gain 0.2). Stabilization against active and passive head movements was not impaired in our cerebellar ataxia patients.

  13. Human-directed social behaviour in dogs shows significant heritability.

    Science.gov (United States)

    Persson, M E; Roth, L S V; Johnsson, M; Wright, D; Jensen, P

    2015-04-01

    Through domestication and co-evolution with humans, dogs have developed abilities to attract human attention, e.g. in a manner of seeking assistance when faced with a problem solving task. The aims of this study were to investigate within breed variation in human-directed contact seeking in dogs and to estimate its genetic basis. To do this, 498 research beagles, bred and kept under standardized conditions, were tested in an unsolvable problem task. Contact seeking behaviours recorded included both eye contact and physical interactions. Behavioural data was summarized through a principal component analysis, resulting in four components: test interactions, social interactions, eye contact and physical contact. Females scored significantly higher on social interactions and physical contact and age had an effect on eye contact scores. Narrow sense heritabilities (h(2) ) of the two largest components were estimated at 0.32 and 0.23 but were not significant for the last two components. These results show that within the studied dog population, behavioural variation in human-directed social behaviours was sex dependent and that the utilization of eye contact seeking increased with age and experience. Hence, heritability estimates indicate a significant genetic contribution to the variation found in human-directed social interactions, suggesting that social skills in dogs have a genetic basis, but can also be shaped and enhanced through individual experiences. This research gives the opportunity to further investigate the genetics behind dogs' social skills, which could also play a significant part into research on human social disorders such as autism. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  14. Gaze-informed, task-situated representation of space in primate hippocampus during virtual navigation

    Science.gov (United States)

    Wirth, Sylvia; Baraduc, Pierre; Planté, Aurélie; Pinède, Serge; Duhamel, Jean-René

    2017-01-01

    To elucidate how gaze informs the construction of mental space during wayfinding in visual species like primates, we jointly examined navigation behavior, visual exploration, and hippocampal activity as macaque monkeys searched a virtual reality maze for a reward. Cells sensitive to place also responded to one or more variables like head direction, point of gaze, or task context. Many cells fired at the sight (and in anticipation) of a single landmark in a viewpoint- or task-dependent manner, simultaneously encoding the animal’s logical situation within a set of actions leading to the goal. Overall, hippocampal activity was best fit by a fine-grained state space comprising current position, view, and action contexts. Our findings indicate that counterparts of rodent place cells in primates embody multidimensional, task-situated knowledge pertaining to the target of gaze, therein supporting self-awareness in the construction of space. PMID:28241007

  15. Design gaze simulation for people with visual disability

    NARCIS (Netherlands)

    Qiu, S.

    2017-01-01

    In face-to-face communication, eye gaze is integral to a conversation to supplement verbal language. The sighted often uses eye gaze to convey nonverbal information in social interactions, which a blind conversation partner cannot access and react. My doctoral research is to design gaze simulation

  16. DIAGNOSIS OF MYASTHENIA GRAVIS USING FUZZY GAZE TRACKING SOFTWARE

    Directory of Open Access Journals (Sweden)

    Javad Rasti

    2015-04-01

    Full Text Available Myasthenia Gravis (MG is an autoimmune disorder, which may lead to paralysis and even death if not treated on time. One of its primary symptoms is severe muscular weakness, initially arising in the eye muscles. Testing the mobility of the eyeball can help in early detection of MG. In this study, software was designed to analyze the ability of the eye muscles to focus in various directions, thus estimating the MG risk. Progressive weakness in gazing at the directions prompted by the software can reveal abnormal fatigue of the eye muscles, which is an alert sign for MG. To assess the user’s ability to keep gazing at a specified direction, a fuzzy algorithm was applied to images of the user’s eyes to determine the position of the iris in relation to the sclera. The results of the tests performed on 18 healthy volunteers and 18 volunteers in early stages of MG confirmed the validity of the suggested software.

  17. Gaze Behavior in a Natural Environment with a Task-Relevant Distractor: How the Presence of a Goalkeeper Distracts the Penalty Taker

    Directory of Open Access Journals (Sweden)

    Johannes Kurz

    2018-01-01

    Full Text Available Gaze behavior in natural scenes has been shown to be influenced not only by top–down factors such as task demands and action goals but also by bottom–up factors such as stimulus salience and scene context. Whereas gaze behavior in the context of static pictures emphasizes spatial accuracy, gazing in natural scenes seems to rely more on where to direct the gaze involving both anticipative components and an evaluation of ongoing actions. Not much is known about gaze behavior in far-aiming tasks in which multiple task-relevant targets and distractors compete for the allocation of visual attention via gaze. In the present study, we examined gaze behavior in the far-aiming task of taking a soccer penalty. This task contains a proximal target, the ball; a distal target, an empty location within the goal; and a salient distractor, the goalkeeper. Our aim was to investigate where participants direct their gaze in a natural environment with multiple potential fixation targets that differ in task relevance and salience. Results showed that the early phase of the run-up seems to be driven by both the salience of the stimulus setting and the need to perform a spatial calibration of the environment. The late run-up, in contrast, seems to be controlled by attentional demands of the task with penalty takers having habitualized a visual routine that is not disrupted by external influences (e.g., the goalkeeper. In addition, when trying to shoot a ball as accurately as possible, penalty takers directed their gaze toward the ball in order to achieve optimal foot-ball contact. These results indicate that whether gaze is driven by salience of the stimulus setting or by attentional demands depends on the phase of the actual task.

  18. Towards Wearable Gaze Supported Augmented Cognition

    DEFF Research Database (Denmark)

    Toshiaki Kurauchi, Andrew; Hitoshi Morimoto, Carlos; Mardanbeigi, Diako

    Augmented cognition applications must deal with the problem of how to exhibit information in an orderly, understandable, and timely fashion. Though context have been suggested to control the kind, amount, and timing of the information delivered, we argue that gaze can be a fundamental tool...... by the wearable computing community to develop a gaze supported augmented cognition application with three interaction modes. The application provides information of the person being looked at. The continuous mode updates information every time the user looks at a different face. The key activated discrete mode...

  19. Eye Contact and Fear of Being Laughed at in a Gaze Discrimination Task

    Directory of Open Access Journals (Sweden)

    Jorge Torres-Marín

    2017-11-01

    Full Text Available Current approaches conceptualize gelotophobia as a personality trait characterized by a disproportionate fear of being laughed at by others. Consistently with this perspective, gelotophobes are also described as neurotic and introverted and as having a paranoid tendency to anticipate derision and mockery situations. Although research on gelotophobia has significantly progressed over the past two decades, no evidence exists concerning the potential effects of gelotophobia in reaction to eye contact. Previous research has pointed to difficulties in discriminating gaze direction as the basis of possible misinterpretations of others’ intentions or mental states. The aim of the present research was to examine whether gelotophobia predisposition modulates the effects of eye contact (i.e., gaze discrimination when processing faces portraying several emotional expressions. In two different experiments, participants performed an experimental gaze discrimination task in which they responded, as quickly and accurately as possible, to the eyes’ directions on faces displaying either a happy, angry, fear, neutral, or sad emotional expression. In particular, we expected trait-gelotophobia to modulate the eye contact effect, showing specific group differences in the happiness condition. The results of Study 1 (N = 40 indicated that gelotophobes made more errors than non-gelotophobes did in the gaze discrimination task. In contrast to our initial hypothesis, the happiness expression did not have any special role in the observed differences between individuals with high vs. low trait-gelotophobia. In Study 2 (N = 40, we replicated the pattern of data concerning gaze discrimination ability, even after controlling for individuals’ scores on social anxiety. Furthermore, in our second experiment, we found that gelotophobes did not exhibit any problem with identifying others’ emotions, or a general incorrect attribution of affective features, such as valence

  20. Looking for Action: Talk and Gaze Home Position in the Airline Cockpit

    Science.gov (United States)

    Nevile, Maurice

    2010-01-01

    This paper considers the embodied nature of discourse for a professional work setting. It examines language in interaction in the airline cockpit, and specifically how shifts in pilots' eye gaze direction can indicate the action of talk, that is, what talk is doing and its relative contribution to work-in-progress. Looking towards the other…

  1. Inflammatory aetiology of human myometrial activation tested using directed graphs.

    Directory of Open Access Journals (Sweden)

    2005-07-01

    Full Text Available THERE ARE THREE MAIN HYPOTHESES FOR THE ACTIVATION OF THE HUMAN UTERUS AT LABOUR: functional progesterone withdrawal, inflammatory stimulation, and oxytocin receptor activation. To test these alternatives we have taken information and data from the literature to develop causal pathway models for the activation of human myometrium. The data provided quantitative RT-PCR results on key genes from samples taken before and during labour. Principal component analysis showed that pre-labour samples form a homogenous group compared to those during labour. We therefore modelled the alternative causal pathways in non-labouring samples using directed graphs and statistically compared the likelihood of the different models using structural equations and D-separation approaches. Using the computer program LISREL, inflammatory activation as a primary event was highly consistent with the data (p = 0.925, progesterone withdrawal, as a primary event, is plausible (p = 0.499, yet comparatively unlikely, oxytocin receptor mediated initiation is less compatible with the data (p = 0.091. DGraph, a software program that creates directed graphs, produced similar results (p= 0.684, p= 0.280, and p = 0.04, respectively. This outcome supports an inflammatory aetiology for human labour. Our results demonstrate the value of directed graphs in determining the likelihood of causal relationships in biology in situations where experiments are not possible.

  2. Direct evidence of milk consumption from ancient human dental calculus.

    Science.gov (United States)

    Warinner, C; Hendy, J; Speller, C; Cappellini, E; Fischer, R; Trachsel, C; Arneborg, J; Lynnerup, N; Craig, O E; Swallow, D M; Fotakis, A; Christensen, R J; Olsen, J V; Liebert, A; Montalva, N; Fiddyment, S; Charlton, S; Mackie, M; Canci, A; Bouwman, A; Rühli, F; Gilbert, M T P; Collins, M J

    2014-11-27

    Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up to the abandonment of the Norse Greenland colonies in the 15(th) century CE.

  3. Earliest directly-dated human skull-cups.

    Directory of Open Access Journals (Sweden)

    Silvia M Bello

    Full Text Available BACKGROUND: The use of human braincases as drinking cups and containers has extensive historic and ethnographic documentation, but archaeological examples are extremely rare. In the Upper Palaeolithic of western Europe, cut-marked and broken human bones are widespread in the Magdalenian (∼15 to 12,000 years BP and skull-cup preparation is an element of this tradition. PRINCIPAL FINDINGS: Here we describe the post-mortem processing of human heads at the Upper Palaeolithic site of Gough's Cave (Somerset, England and identify a range of modifications associated with the production of skull-cups. New analyses of human remains from Gough's Cave demonstrate the skilled post-mortem manipulation of human bodies. Results of the research suggest the processing of cadavers for the consumption of body tissues (bone marrow, accompanied by meticulous shaping of cranial vaults. The distribution of cut-marks and percussion features indicates that the skulls were scrupulously 'cleaned' of any soft tissues, and subsequently modified by controlled removal of the facial region and breakage of the cranial base along a sub-horizontal plane. The vaults were also 'retouched', possibly to make the broken edges more regular. This manipulation suggests the shaping of skulls to produce skull-cups. CONCLUSIONS: Three skull-cups have been identified amongst the human bones from Gough's Cave. New ultrafiltered radiocarbon determinations provide direct dates of about 14,700 cal BP, making these the oldest directly dated skull-cups and the only examples known from the British Isles.

  4. Adaptive Gaze Strategies for Locomotion with Constricted Visual Field

    Directory of Open Access Journals (Sweden)

    Colas N. Authié

    2017-07-01

    Full Text Available In retinitis pigmentosa (RP, loss of peripheral visual field accounts for most difficulties encountered in visuo-motor coordination during locomotion. The purpose of this study was to accurately assess the impact of peripheral visual field loss on gaze strategies during locomotion, and identify compensatory mechanisms. Nine RP subjects presenting a central visual field limited to 10–25° in diameter, and nine healthy subjects were asked to walk in one of three directions—straight ahead to a visual target, leftward and rightward through a door frame, with or without obstacle on the way. Whole body kinematics were recorded by motion capture, and gaze direction in space was reconstructed using an eye-tracker. Changes in gaze strategies were identified in RP subjects, including extensive exploration prior to walking, frequent fixations of the ground (even knowing no obstacle was present, of door edges, essentially of the proximal one, of obstacle edge/corner, and alternating door edges fixations when approaching the door. This was associated with more frequent, sometimes larger rapid-eye-movements, larger movements, and forward tilting of the head. Despite the visual handicap, the trajectory geometry was identical between groups, with a small decrease in walking speed in RPs. These findings identify the adaptive changes in sensory-motor coordination, in order to ensure visual awareness of the surrounding, detect changes in spatial configuration, collect information for self-motion, update the postural reference frame, and update egocentric distances to environmental objects. They are of crucial importance for the design of optimized rehabilitation procedures.

  5. Adaptive Gaze Strategies for Locomotion with Constricted Visual Field

    Science.gov (United States)

    Authié, Colas N.; Berthoz, Alain; Sahel, José-Alain; Safran, Avinoam B.

    2017-01-01

    In retinitis pigmentosa (RP), loss of peripheral visual field accounts for most difficulties encountered in visuo-motor coordination during locomotion. The purpose of this study was to accurately assess the impact of peripheral visual field loss on gaze strategies during locomotion, and identify compensatory mechanisms. Nine RP subjects presenting a central visual field limited to 10–25° in diameter, and nine healthy subjects were asked to walk in one of three directions—straight ahead to a visual target, leftward and rightward through a door frame, with or without obstacle on the way. Whole body kinematics were recorded by motion capture, and gaze direction in space was reconstructed using an eye-tracker. Changes in gaze strategies were identified in RP subjects, including extensive exploration prior to walking, frequent fixations of the ground (even knowing no obstacle was present), of door edges, essentially of the proximal one, of obstacle edge/corner, and alternating door edges fixations when approaching the door. This was associated with more frequent, sometimes larger rapid-eye-movements, larger movements, and forward tilting of the head. Despite the visual handicap, the trajectory geometry was identical between groups, with a small decrease in walking speed in RPs. These findings identify the adaptive changes in sensory-motor coordination, in order to ensure visual awareness of the surrounding, detect changes in spatial configuration, collect information for self-motion, update the postural reference frame, and update egocentric distances to environmental objects. They are of crucial importance for the design of optimized rehabilitation procedures. PMID:28798674

  6. Off-the-Shelf Gaze Interaction

    DEFF Research Database (Denmark)

    San Agustin, Javier

    People with severe motor-skill disabilities are often unable to use standard input devices such as a mouse or a keyboard to control a computer and they are, therefore, in strong need for alternative input devices. Gaze tracking offers them the possibility to use the movements of their eyes to int...

  7. The Use of Gaze to Control Drones

    DEFF Research Database (Denmark)

    Hansen, John Paulin; Alapetite, Alexandre; MacKenzie, I. Scott

    2014-01-01

    This paper presents an experimental investigation of gaze-based control modes for unmanned aerial vehicles (UAVs or “drones”). Ten participants performed a simple flying task. We gathered empirical measures, including task completion time, and examined the user experience for difficulty, reliabil...

  8. Between Gazes: Feminist, Queer, and 'Other' Films

    DEFF Research Database (Denmark)

    Elias, Camelia

    In this book Camelia Elias introduces key terms in feminist, queer, and postcolonial/diaspora film. Taking her point of departure in the question, "what do you want from me?" she detours through Lacanian theory of the gaze and reframes questions of subjectivity and representation in an entertaining...

  9. Gaze interaction with textual user interface

    DEFF Research Database (Denmark)

    Paulin Hansen, John; Lund, Haakon; Madsen, Janus Askø

    2015-01-01

    ” option for text navigation. People readily understood how to execute RSVP command prompts and a majority of them preferred gaze input to a pen pointer. We present the concept of a smartwatch that can track eye movements and mediate command options whenever in proximity of intelligent devices...

  10. Directional and balancing selection in human beta-defensins

    Directory of Open Access Journals (Sweden)

    Armour John AL

    2008-04-01

    Full Text Available Abstract Background In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. Results We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93, is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Conclusion Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

  11. Directional and balancing selection in human beta-defensins.

    Science.gov (United States)

    Hollox, Edward J; Armour, John A L

    2008-04-16

    In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93), is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

  12. Gaze characteristics of elite and near-elite athletes in ice hockey defensive tactics.

    Science.gov (United States)

    Martell, Stephen G; Vickers, Joan N

    2004-04-01

    Traditional visual search experiments, where the researcher pre-selects video-based scenes for the participant to respond to, shows that elite players make more efficient decisions than non-elites, but disagree on how they temporally regulate their gaze. Using the vision-in-action [J.N. Vickers, J. Exp. Psychol.: Human Percept. Perform. 22 (1996) 342] approach, we tested whether the significant gaze that differentiates elite and non-elite athletes occurred either: early in the task and was of more rapid duration [A.M. Williams et al., Res. Quart. Exer. Sport 65 (1994) 127; A.M. Williams and K. Davids, Res. Quart. Exer. Sport 69 (1998) 111], or late in the task and was of longer duration [W. Helsen, J.M. Pauwels, A cognitive approach to visual search in sport, in: D. Brogan, K. Carr (Eds.), Visual Search, vol. II, Taylor and Francis, London, 1992], or whether a more complex gaze control strategy was used that consisted of both early and rapid fixations followed by a late fixation of long duration prior to the final execution. We tested this using a live defensive zone task in ice hockey. Results indicated that athletes temporally regulated their gaze using two different gaze control strategies. First, fixation/tracking (F/T) gaze early in the trial were significantly shorter than the final F/T and confirmed that the elite group fixated the tactical locations more rapidly than the non-elite on successful plays. And secondly, the final F/T prior to critical movement initiation (i.e. F/T-1) was significantly longer for both groups, averaging 30% of the final part of the phase and occurred as the athletes isolated a single object or location to end the play. The results imply that expertise in defensive tactics is defined by a cascade of F/T, which began with the athletes fixating or tracking specific locations for short durations at the beginning of the play, and concluded with a final gaze of long duration to a relatively stable target at the end. The results are

  13. MEG evidence for dynamic amygdala modulations by gaze and facial emotions.

    Directory of Open Access Journals (Sweden)

    Thibaud Dumas

    Full Text Available Amygdala is a key brain region for face perception. While the role of amygdala in the perception of facial emotion and gaze has been extensively highlighted with fMRI, the unfolding in time of amydgala responses to emotional versus neutral faces with different gaze directions is scarcely known.Here we addressed this question in healthy subjects using MEG combined with an original source imaging method based on individual amygdala volume segmentation and the localization of sources in the amygdala volume. We found an early peak of amygdala activity that was enhanced for fearful relative to neutral faces between 130 and 170 ms. The effect of emotion was again significant in a later time range (310-350 ms. Moreover, the amygdala response was greater for direct relative averted gaze between 190 and 350 ms, and this effect was selective of fearful faces in the right amygdala.Altogether, our results show that the amygdala is involved in the processing and integration of emotion and gaze cues from faces in different time ranges, thus underlining its role in multiple stages of face perception.

  14. LAND WHERE YOU LOOK? – FUNCTIONAL RELATIONSHIPS BETWEEN GAZE AND MOVEMENT BEHAVIOUR IN A BACKWARD SALTO

    Directory of Open Access Journals (Sweden)

    Thomas Heinen

    2012-07-01

    Full Text Available In most everyday actions the eyes look towards objects and locations they are engaged with in a specific task and this information is used to guide the corresponding action. The question is, however, whether this strategy also holds for skills incorporating a whole-body rotation in sport. Therefore, the goal of this study was to investigate relationships between gaze behaviour and movement behaviour in a complex gymnastics skill, namely the backward salto performed as a dismount on the uneven bars. Thirteen expert gymnasts were instructed to fixate a light spot on the landing mat during the downswing phase when performing a backward salto as dismount. The location of the light spot was varied systematically with regard to each gymnast’s individual landing distance. Time-discrete kinematic parameters of the swing motion and the dismount were measured. It was expected that fixating the gaze towards different locations of the light spot on the landing mat would directly affect the landing location. We had, however, no specific predictions on the effects of manipulating gaze direction on the remaining kinematic parameters. The hip angle at the top of the backswing, the duration of the downswing phase, the hip angle prior to kick-through, and the landing distance varied clearly as a function of the location of the light spot. It is concluded that fixating the gaze towards the landing mat serves the function to execute the skill in a way to land on a particular location.

  15. MEG Evidence for Dynamic Amygdala Modulations by Gaze and Facial Emotions

    Science.gov (United States)

    Dumas, Thibaud; Dubal, Stéphanie; Attal, Yohan; Chupin, Marie; Jouvent, Roland; Morel, Shasha; George, Nathalie

    2013-01-01

    Background Amygdala is a key brain region for face perception. While the role of amygdala in the perception of facial emotion and gaze has been extensively highlighted with fMRI, the unfolding in time of amydgala responses to emotional versus neutral faces with different gaze directions is scarcely known. Methodology/Principal Findings Here we addressed this question in healthy subjects using MEG combined with an original source imaging method based on individual amygdala volume segmentation and the localization of sources in the amygdala volume. We found an early peak of amygdala activity that was enhanced for fearful relative to neutral faces between 130 and 170 ms. The effect of emotion was again significant in a later time range (310–350 ms). Moreover, the amygdala response was greater for direct relative averted gaze between 190 and 350 ms, and this effect was selective of fearful faces in the right amygdala. Conclusion Altogether, our results show that the amygdala is involved in the processing and integration of emotion and gaze cues from faces in different time ranges, thus underlining its role in multiple stages of face perception. PMID:24040190

  16. Foreign Direct Investments and Human Capital Development in Subsaharan Africa

    Directory of Open Access Journals (Sweden)

    Luc NEMBOT NDEFFO

    2010-12-01

    Full Text Available The objective of the present study is to estimate the impact of foreign direct investments on human capital development in 32 Subsaharan African countries over the period 1980 – 2005. Human capital is captured by the percentage of children in full-time education in primary and secondary schools. Panel data regressions are used for the estimations. The results show a correlation not only between FDI and the percentage of children in full-time education in primary school but also between the FDI and the percentage of children in full-time education in secondary school. These results are not significant for that. This shows that FDI directed towards Sub-Saharan Africa still remain insufficient. That is why a lot of effort should be made in order to favour the attraction of FDI in this part of the continent. The other variables which have a positive and significant impact on the percentage of children in full-time education are: the domestic investment rate, public sector expenditures, life expectancy at birth and the growth rate of the gross domestic product per capita.

  17. Human platelet vasopressin receptor identification by direct ultraviolet photoaffinity labeling

    International Nuclear Information System (INIS)

    Thibonnier, M.

    1987-01-01

    Tritiated vasopressin ([ 3 H]AVP) was directly crosslinked to its human platelet receptor by using an ultraviolet irradiation procedure. After preincubation with [ 3 H]AVP, the hydrodynamic parameters of the hormone-receptor complexes solubilized with 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate were derived from Sephacryl S-300 superfine gel filtration and from sucrose density gradient ultracentrifugation experiments. The following values were obtained: Stoke's radius = 5.48 +/- 0.1 nm, apparent sedimentation coefficient = 5.55 +/- 0.1 S, and calculated molecular weight = 132,000. On sodium dodecyl sulfate-8% polyacrylamide slab gel electrophoresis under reducing conditions, [ 3 H]AVP preferentially and specifically labeled a 125,000-dalton protein. The labeling of this protein was suppressed by addition of excess cold vasopressin, whereas angiotensin II did not inhibit incorporation of tritiated vasopressin in this protein. These results suggest that direct UV-photoaffinity labelling with [ 3 H]AVP is a suitable tool for the purification of the human platelet vasopressin receptor

  18. Directional asymmetries in human smooth pursuit eye movements.

    Science.gov (United States)

    Ke, Sally R; Lam, Jessica; Pai, Dinesh K; Spering, Miriam

    2013-06-27

    Humans make smooth pursuit eye movements to bring the image of a moving object onto the fovea. Although pursuit accuracy is critical to prevent motion blur, the eye often falls behind the target. Previous studies suggest that pursuit accuracy differs between motion directions. Here, we systematically assess asymmetries in smooth pursuit. In experiment 1, binocular eye movements were recorded while observers (n = 20) tracked a small spot of light moving along one of four cardinal or diagonal axes across a featureless background. We analyzed pursuit latency, acceleration, peak velocity, gain, and catch-up saccade latency, number, and amplitude. In experiment 2 (n = 22), we examined the effects of spatial location and constrained stimulus motion within the upper or lower visual field. Pursuit was significantly faster (higher acceleration, peak velocity, and gain) and smoother (fewer and later catch-up saccades) in response to downward versus upward motion in both the upper and the lower visual fields. Pursuit was also more accurate and smoother in response to horizontal versus vertical motion. CONCLUSIONS. Our study is the first to report a consistent up-down asymmetry in human adults, regardless of visual field. Our findings suggest that pursuit asymmetries are adaptive responses to the requirements of the visual context: preferred motion directions (horizontal and downward) are more critical to our survival than nonpreferred ones.

  19. Studying the influence of race on the gaze cueing effect using eye tracking method

    Directory of Open Access Journals (Sweden)

    Galina Ya. Menshikova

    2017-06-01

    Full Text Available The gaze direction of another person is an important social cue, allowing us to orient quickly in social interactions. The effect of short-term redirection of visual attention to the same object that other people are looking at is known as the gaze cueing effect. There is evidence that the strength of this effect depends on many social factors, such as the trust in a partner, her/his gender, social attitudes, etc. In our study we investigated the influence of race of face stimuli on the strength of the gaze cueing effect. Using the modified Posner Cueing Task an attentional shift was assessed in a scene where avatar faces of different race were used as distractors. Participants were instructed to fix the black dot in the centre of the screen until it changes colour, and then as soon as possible to make a rightward or leftward saccade, depending on colour of a fixed point. A male distractor face was shown in the centre of the screen simultaneously with a fixed point. The gaze direction of the distractor face changed from straight ahead to rightward or leftward at the moment when colour of a fixed point changed. It could be either congruent or incongruent with the saccade direction. We used face distractors of three race categories: Caucasian (own race faces, Asian and African (other race faces. Twenty five Caucasian participants took part in our study. The results showed that the race of face distractors influence the strength of the gaze cueing effect, that manifested in the change of latency and velocity of the ongoing saccades.

  20. Directed neuronal differentiation of human embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Noggle Scott A

    2003-10-01

    Full Text Available Abstract Background We have developed a culture system for the efficient and directed differentiation of human embryonic stem cells (HESCs to neural precursors and neurons. HESC were maintained by manual passaging and were differentiated to a morphologically distinct OCT-4+/SSEA-4- monolayer cell type prior to the derivation of embryoid bodies. Embryoid bodies were grown in suspension in serum free conditions, in the presence of 50% conditioned medium from the human hepatocarcinoma cell line HepG2 (MedII. Results A neural precursor population was observed within HESC derived serum free embryoid bodies cultured in MedII conditioned medium, around 7–10 days after derivation. The neural precursors were organized into rosettes comprised of a central cavity surrounded by ring of cells, 4 to 8 cells in width. The central cells within rosettes were proliferating, as indicated by the presence of condensed mitotic chromosomes and by phosphoHistone H3 immunostaining. When plated and maintained in adherent culture, the rosettes of neural precursors were surrounded by large interwoven networks of neurites. Immunostaining demonstrated the expression of nestin in rosettes and associated non-neuronal cell types, and a radial expression of Map-2 in rosettes. Differentiated neurons expressed the markers Map-2 and Neurofilament H, and a subpopulation of the neurons expressed tyrosine hydroxylase, a marker for dopaminergic neurons. Conclusion This novel directed differentiation approach led to the efficient derivation of neuronal cultures from HESCs, including the differentiation of tyrosine hydroxylase expressing neurons. HESC were morphologically differentiated to a monolayer OCT-4+ cell type, which was used to derive embryoid bodies directly into serum free conditions. Exposure to the MedII conditioned medium enhanced the derivation of neural precursors, the first example of the effect of this conditioned medium on HESC.

  1. Sleep-dependent directional coupling between human neocortex and hippocampus.

    Science.gov (United States)

    Wagner, Tobias; Axmacher, Nikolai; Lehnertz, Klaus; Elger, Christian E; Fell, Jürgen

    2010-02-01

    Complex interactions between neocortex and hippocampus are the neural basis of memory formation. Two-step theories of memory formation suggest that initial encoding of novel information depends on the induction of rapid plasticity within the hippocampus, and is followed by a second sleep-dependent step of memory consolidation. These theories predict information flow from the neocortex into the hippocampus during waking state and in the reverse direction during sleep. However, experimental evidence that interactions between hippocampus and neocortex have a predominant direction which reverses during sleep rely on cross-correlation analysis of data from animal experiments and yielded inconsistent results. Here, we investigated directional coupling in intracranial EEG data from human subjects using a phase-modeling approach which is well suited to reveal functional interdependencies in oscillatory data. In general, we observed that the anterior hippocampus predominantly drives nearby and remote brain regions. Surprisingly, however, the influence of neocortical regions on the hippocampus significantly increased during sleep as compared to waking state. These results question the standard model of hippocampal-neocortical interactions and suggest that sleep-dependent consolidation is accomplished by an active retrieval of hippocampal information by the neocortex. Copyright 2009 Elsevier Srl. All rights reserved.

  2. Towards gaze-controlled platform games

    DEFF Research Database (Denmark)

    Muñoz, Jorge; Yannakakis, Georgios N.; Mulvey, Fiona

    2011-01-01

    This paper introduces the concept of using gaze as a sole modality for fully controlling player characters of fast-paced action computer games. A user experiment is devised to collect gaze and gameplay data from subjects playing a version of the popular Super Mario Bros platform game. The initial...... analysis shows that there is a rather limited grid around Mario where the efficient player focuses her attention the most while playing the game. The useful grid as we name it, projects the amount of meaningful visual information a designer should use towards creating successful player character...... controllers with the use of artificial intelligence for a platform game like Super Mario. Information about the eyes' position on the screen and the state of the game are utilized as inputs of an artificial neural network, which is trained to approximate which keyboard action is to be performed at each game...

  3. Mental state attribution and the gaze cueing effect.

    Science.gov (United States)

    Cole, Geoff G; Smith, Daniel T; Atkinson, Mark A

    2015-05-01

    Theory of mind is said to be possessed by an individual if he or she is able to impute mental states to others. Recently, some authors have demonstrated that such mental state attributions can mediate the "gaze cueing" effect, in which observation of another individual shifts an observer's attention. One question that follows from this work is whether such mental state attributions produce mandatory modulations of gaze cueing. Employing the basic gaze cueing paradigm, together with a technique commonly used to assess mental-state attribution in nonhuman animals, we manipulated whether the gazing agent could see the same thing as the participant (i.e., the target) or had this view obstructed by a physical barrier. We found robust gaze cueing effects, even when the observed agent in the display could not see the same thing as the participant. These results suggest that the attribution of "seeing" does not necessarily modulate the gaze cueing effect.

  4. Clinician's gaze behaviour in simulated paediatric emergencies.

    Science.gov (United States)

    McNaughten, Ben; Hart, Caroline; Gallagher, Stephen; Junk, Carol; Coulter, Patricia; Thompson, Andrew; Bourke, Thomas

    2018-03-07

    Differences in the gaze behaviour of experts and novices are described in aviation and surgery. This study sought to describe the gaze behaviour of clinicians from different training backgrounds during a simulated paediatric emergency. Clinicians from four clinical areas undertook a simulated emergency. Participants wore SMI (SensoMotoric Instruments) eye tracking glasses. We measured the fixation count and dwell time on predefined areas of interest and the time taken to key clinical interventions. Paediatric intensive care unit (PICU) consultants performed best and focused longer on the chest and airway. Paediatric consultants and trainees spent longer looking at the defibrillator and algorithm (51 180 ms and 50 551 ms, respectively) than the PICU and paediatric emergency medicine consultants. This study is the first to describe differences in the gaze behaviour between experts and novices in a resuscitation. They mirror those described in aviation and surgery. Further research is needed to evaluate the potential use of eye tracking as an educational tool. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  5. [Left lateral gaze paresis due to subcortical hematoma in the right precentral gyrus].

    Science.gov (United States)

    Sato, K; Takamori, M

    1998-03-01

    We report a case of transient left lateral gaze paresis due to a hemorrhagic lesion restricted in the right precentral gyrus. A 74-year-old female experienced a sudden clumsiness of the left upper extremity. A neurological examination revealed a left central facial paresis, distal dominant muscle weakness in the left upper limb and left lateral gaze paresis. There were no other focal neurological signs. Laboratory data were all normal. Brain CTs and MRIs demonstrated a subcortical hematoma in the right precentral gyrus. The neurological symptoms and signs disappeared over seven days. A recent physiological study suggested that the human frontal eye field (FEF) is located in the posterior part of the middle frontal gyrus (Brodmann's area 8) and the precentral gyrus around the precentral sulcus. More recent studies stressed the role of the precentral sulcus and the precentral gyrus. Our case supports those physiological findings. The hematoma affected both the FEF and its underlying white matter in our case. We assume the lateral gaze paresis is attributable to the disruption of the fibers from the FEF. It is likely that fibers for motor control of the face, upper extremity, and lateral gaze lie adjacently in the subcortical area.

  6. Gaze strategies during visually-guided versus memory-guided grasping.

    Science.gov (United States)

    Prime, Steven L; Marotta, Jonathan J

    2013-03-01

    Vision plays a crucial role in guiding motor actions. But sometimes we cannot use vision and must rely on our memory to guide action-e.g. remembering where we placed our eyeglasses on the bedside table when reaching for them with the lights off. Recent studies show subjects look towards the index finger grasp position during visually-guided precision grasping. But, where do people look during memory-guided grasping? Here, we explored the gaze behaviour of subjects as they grasped a centrally placed symmetrical block under open- and closed-loop conditions. In Experiment 1, subjects performed grasps in either a visually-guided task or memory-guided task. The results show that during visually-guided grasping, gaze was first directed towards the index finger's grasp point on the block, suggesting gaze targets future grasp points during the planning of the grasp. Gaze during memory-guided grasping was aimed closer to the blocks' centre of mass from block presentation to the completion of the grasp. In Experiment 2, subjects performed an 'immediate grasping' task in which vision of the block was removed immediately at the onset of the reach. Similar to the visually-guided results from Experiment 1, gaze was primarily directed towards the index finger location. These results support the 2-stream theory of vision in that motor planning with visual feedback at the onset of the movement is driven primarily by real-time visuomotor computations of the dorsal stream, whereas grasping remembered objects without visual feedback is driven primarily by the perceptual memory representations mediated by the ventral stream.

  7. Mechanical impedance of the human body in vertical direction.

    Science.gov (United States)

    Holmlund, P; Lundström, R; Lindberg, L

    2000-08-01

    The mechanical impedance of the human body in sitting posture and vertical direction was measured during different experimental conditions, such as vibration level (0.5-1.4 m/s2), frequency (2-100 Hz), body weight (57-92 kg), relaxed and erect upper body posture. The outcome shows that impedance increases with frequency up to a peak at about 5 Hz after which it decreases in a complex manner which includes two additional peaks. The frequency at which the first and second impedance peak occurs decreases with higher vibration level. Erect, compared with relaxed body posture resulted in higher impedance magnitudes and with peaks located at somewhat higher frequencies. Heavy persons show higher impedance magnitudes and peaks at lower frequencies.

  8. Characterization of monoclonal antibodies directed against human thyroid stimulating hormone

    International Nuclear Information System (INIS)

    Soos, M.; Siddle, K.

    1982-01-01

    Monoclonal antibodies directed against human thyroid stimulating hormone (TSH) were obtained from hybrid myelomas, following fusion of mouse NSI myeloma cells with mouse spleen cells. Ten different antibodies were obtained from 4 separate fusions. Eight antibodies were of the IgG 1 subclass. Affinities of antibodies for TSH were in the range 2 x 10 8 -5 x 10 10 M -1 . Five of the antibodies were specific for TSH and did not react with LH, FSH or hCG. The remaining antibodies reacted with all these hormones and were assumed to recognise their common (α) subunit. The 5 specific antibodies fell into 3 subgroups recognising distinct antigenic determinants, whereas the 5 non-specific antibodies recognised a single determinant or closely related set of sites. It is concluded that these antibodies should be valuable reagents for use in sensitive and specific two-site immunoradiometric assays. (Auth.)

  9. Social interactions through the eyes of macaques and humans.

    Directory of Open Access Journals (Sweden)

    Richard McFarland

    Full Text Available Group-living primates frequently interact with each other to maintain social bonds as well as to compete for valuable resources. Observing such social interactions between group members provides individuals with essential information (e.g. on the fighting ability or altruistic attitude of group companions to guide their social tactics and choice of social partners. This process requires individuals to selectively attend to the most informative content within a social scene. It is unclear how non-human primates allocate attention to social interactions in different contexts, and whether they share similar patterns of social attention to humans. Here we compared the gaze behaviour of rhesus macaques and humans when free-viewing the same set of naturalistic images. The images contained positive or negative social interactions between two conspecifics of different phylogenetic distance from the observer; i.e. affiliation or aggression exchanged by two humans, rhesus macaques, Barbary macaques, baboons or lions. Monkeys directed a variable amount of gaze at the two conspecific individuals in the images according to their roles in the interaction (i.e. giver or receiver of affiliation/aggression. Their gaze distribution to non-conspecific individuals was systematically varied according to the viewed species and the nature of interactions, suggesting a contribution of both prior experience and innate bias in guiding social attention. Furthermore, the monkeys' gaze behavior was qualitatively similar to that of humans, especially when viewing negative interactions. Detailed analysis revealed that both species directed more gaze at the face than the body region when inspecting individuals, and attended more to the body region in negative than in positive social interactions. Our study suggests that monkeys and humans share a similar pattern of role-sensitive, species- and context-dependent social attention, implying a homologous cognitive mechanism of

  10. ANALYSIS OF THE GAZE BEHAVIOUR OF THE WORKER ON THE CARBURETOR ASSEMBLY TASK

    Directory of Open Access Journals (Sweden)

    Novie Susanto

    2015-06-01

    Full Text Available This study presents analysis of the area of interest (AOI and the gaze behavior of human during assembly task. This study aims at investigating the human behavior in detail using an eye‐tracking system during assembly task using LEGO brick and an actual manufactured product, a carburetor. An analysis using heat map data based on the recorded videos from the eye-tracking system is taken into account to examine and investigate the gaze behavior of human. The results of this study show that the carburetor assembly requires more attention than the product made from LEGO bricks. About 50% of the participants experience the necessity to visually inspect the interim state of the work object during the simulation of the assembly sequence on the screen. They also show the tendency to want to be more certain about part fitting in the actual work object.

  11. Human genome sequencing with direct x-ray holographic imaging

    International Nuclear Information System (INIS)

    Rhodes, C.K.

    1993-01-01

    Direct holographic imaging of biological materials is widely applicable to the study of the structure, properties and action of genetic material. This particular application involves the sequencing of the human genome where prospective genomic imaging technology is composed of three subtechnologies, name an x-ray holographic camera, suitable chemistry and enzymology for the preparation of tagged DNA samples, and the illuminator in the form of an x-ray laser. We report appropriate x-ray camera, embodied by the instrument developed by MCR, is available and that suitable chemical and enzymatic procedures exist for the preparation of the necessary tagged DNA strands. Concerning the future development of the x-ray illuminator. We find that a practical small scale x-ray light source is indeed feasible. This outcome requires the use of unconventional physical processes in order to achieve the necessary power-compression in the amplifying medium. The understanding of these new physical mechanisms is developing rapidly. Importantly, although the x-ray source does not currently exist, the understanding of these new physical mechanisms is developing rapidly and the research has established the basic scaling laws that will determine the properties of the x-ray illuminator. When this x-ray source becomes available, an extremely rapid and cost effective instrument for 3-D imaging of biological materials can be applied to a wide range of biological structural assays, including the base-pair sequencing of the human genome and many questions regarding its higher levels of organization

  12. Direct Electrical Stimulation in the Human Brain Disrupts Melody Processing.

    Science.gov (United States)

    Garcea, Frank E; Chernoff, Benjamin L; Diamond, Bram; Lewis, Wesley; Sims, Maxwell H; Tomlinson, Samuel B; Teghipco, Alexander; Belkhir, Raouf; Gannon, Sarah B; Erickson, Steve; Smith, Susan O; Stone, Jonathan; Liu, Lynn; Tollefson, Trenton; Langfitt, John; Marvin, Elizabeth; Pilcher, Webster H; Mahon, Bradford Z

    2017-09-11

    Prior research using functional magnetic resonance imaging (fMRI) [1-4] and behavioral studies of patients with acquired or congenital amusia [5-8] suggest that the right posterior superior temporal gyrus (STG) in the human brain is specialized for aspects of music processing (for review, see [9-12]). Intracranial electrical brain stimulation in awake neurosurgery patients is a powerful means to determine the computations supported by specific brain regions and networks [13-21] because it provides reversible causal evidence with high spatial resolution (for review, see [22, 23]). Prior intracranial stimulation or cortical cooling studies have investigated musical abilities related to reading music scores [13, 14] and singing familiar songs [24, 25]. However, individuals with amusia (congenitally, or from a brain injury) have difficulty humming melodies but can be spared for singing familiar songs with familiar lyrics [26]. Here we report a detailed study of a musician with a low-grade tumor in the right temporal lobe. Functional MRI was used pre-operatively to localize music processing to the right STG, and the patient subsequently underwent awake intraoperative mapping using direct electrical stimulation during a melody repetition task. Stimulation of the right STG induced "music arrest" and errors in pitch but did not affect language processing. These findings provide causal evidence for the functional segregation of music and language processing in the human brain and confirm a specific role of the right STG in melody processing. VIDEO ABSTRACT. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Evidence for impairments in using static line drawings of eye gaze cues to orient visual-spatial attention in children with high functioning autism.

    Science.gov (United States)

    Goldberg, Melissa C; Mostow, Allison J; Vecera, Shaun P; Larson, Jennifer C Gidley; Mostofsky, Stewart H; Mahone, E Mark; Denckla, Martha B

    2008-09-01

    We examined the ability to use static line drawings of eye gaze cues to orient visual-spatial attention in children with high functioning autism (HFA) compared to typically developing children (TD). The task was organized such that on valid trials, gaze cues were directed toward the same spatial location as the appearance of an upcoming target, while on invalid trials gaze cues were directed to an opposite location. Unlike TD children, children with HFA showed no advantage in reaction time (RT) on valid trials compared to invalid trials (i.e., no significant validity effect). The two stimulus onset asynchronies (200 ms, 700 ms) did not differentially affect these findings. The results suggest that children with HFA show impairments in utilizing static line drawings of gaze cues to orient visual-spatial attention.

  14. Ultraviolet radiation directly induces pigment production by cultured human melanocytes

    International Nuclear Information System (INIS)

    Friedmann, P.S.; Gilchrest, B.A.

    1987-01-01

    In humans the major stimulus for cutaneous pigmentation is ultraviolet radiation (UVR). Little is known about the mechanism underlying this response, in part because of the complexity of interactions in whole epidermis. Using a recently developed culture system, human melanocytes were exposed daily to a physiologic range of UVR doses from a solar simulator. Responses were determined 24 hours after the last exposure. There was a dose-related increase in melanin content per cell and uptake of 14 C-DOPA, accompanied by growth inhibition. Cells from donors of different racial origin gave proportionately similar increases in melanin, although there were approximately tenfold differences in basal values. Light and electron microscopy revealed UVR-stimulated increases in dendricity as well as melanosome number and degree of melanization, analogous to the well-recognized melanocyte changes following sun exposure of intact skin. Similar responses were seen with Cloudman S91 melanoma cells, although this murine cell line required lower UVR dosages and fewer exposures for maximal stimulation. These data establish that UVR is capable of directly stimulating melanogenesis. Because cyclic AMP elevation has been associated in some settings with increased pigment production by cultured melanocytes, preliminary experiments were conducted to see if the effects of UVR were mediated by cAMP. Both alpha-MSH and isobutylmethylxanthine (IBMX), as positive controls, caused a fourfold increase in cAMP level in human melanocytes and/or S91 cells, but following a dose of UVR sufficient to stimulate pigment production there was no change in cAMP level up to 4 hours after exposure. Thus, it appears that the UVR-induced melanogenesis is mediated by cAMP-independent mechanisms

  15. Gaze Bias in Preference Judgments by Younger and Older Adults

    Directory of Open Access Journals (Sweden)

    Toshiki Saito

    2017-08-01

    Full Text Available Individuals’ gaze behavior reflects the choice they will ultimately make. For example, people confronting a choice among multiple stimuli tend to look longer at stimuli that are subsequently chosen than at other stimuli. This tendency, called the gaze bias effect, is a key aspect of visual decision-making. Nevertheless, no study has examined the generality of the gaze bias effect in older adults. Here, we used a two-alternative forced-choice task (2AFC to compare the gaze behavior reflective of different stages of decision processes demonstrated by younger and older adults. Participants who had viewed two faces were instructed to choose the one that they liked/disliked or the one that they judged to be more/less similar to their own face. Their eye movements were tracked while they chose. The results show that the gaze bias effect occurred during the remaining time in both age groups irrespective of the decision type. However, no gaze bias effect was observed for the preference judgment during the first dwell time. Our study demonstrated that the gaze bias during the remaining time occurred regardless of decision-making task and age. Further study using diverse participants, such as clinic patients or infants, may help to generalize the gaze bias effect and to elucidate the mechanisms underlying the gaze bias.

  16. Gaze inspired subtitle position evaluation for MOOCs videos

    Science.gov (United States)

    Chen, Hongli; Yan, Mengzhen; Liu, Sijiang; Jiang, Bo

    2017-06-01

    Online educational resources, such as MOOCs, is becoming increasingly popular, especially in higher education field. One most important media type for MOOCs is course video. Besides traditional bottom-position subtitle accompany to the videos, in recent years, researchers try to develop more advanced algorithms to generate speaker-following style subtitles. However, the effectiveness of such subtitle is still unclear. In this paper, we investigate the relationship between subtitle position and the learning effect after watching the video on tablet devices. Inspired with image based human eye tracking technique, this work combines the objective gaze estimation statistics with subjective user study to achieve a convincing conclusion - speaker-following subtitles are more suitable for online educational videos.

  17. Coupled motions direct electrons along human microsomal P450 Chains.

    Directory of Open Access Journals (Sweden)

    Christopher R Pudney

    2011-12-01

    Full Text Available Protein domain motion is often implicated in biological electron transfer, but the general significance of motion is not clear. Motion has been implicated in the transfer of electrons from human cytochrome P450 reductase (CPR to all microsomal cytochrome P450s (CYPs. Our hypothesis is that tight coupling of motion with enzyme chemistry can signal "ready and waiting" states for electron transfer from CPR to downstream CYPs and support vectorial electron transfer across complex redox chains. We developed a novel approach to study the time-dependence of dynamical change during catalysis that reports on the changing conformational states of CPR. FRET was linked to stopped-flow studies of electron transfer in CPR that contains donor-acceptor fluorophores on the enzyme surface. Open and closed states of CPR were correlated with key steps in the catalytic cycle which demonstrated how redox chemistry and NADPH binding drive successive opening and closing of the enzyme. Specifically, we provide evidence that reduction of the flavin moieties in CPR induces CPR opening, whereas ligand binding induces CPR closing. A dynamic reaction cycle was created in which CPR optimizes internal electron transfer between flavin cofactors by adopting closed states and signals "ready and waiting" conformations to partner CYP enzymes by adopting more open states. This complex, temporal control of enzyme motion is used to catalyze directional electron transfer from NADPH→FAD→FMN→heme, thereby facilitating all microsomal P450-catalysed reactions. Motions critical to the broader biological functions of CPR are tightly coupled to enzyme chemistry in the human NADPH-CPR-CYP redox chain. That redox chemistry alone is sufficient to drive functionally necessary, large-scale conformational change is remarkable. Rather than relying on stochastic conformational sampling, our study highlights a need for tight coupling of motion to enzyme chemistry to give vectorial electron

  18. Direct methods for measuring radionuclides in the human body

    International Nuclear Information System (INIS)

    1996-01-01

    Occupational exposure leading to intakes of internally incorporated radionuclides can occur as a result of various activities. This includes work associated with the different stages of the nuclear fuel cycle, the use of radioactive sources in medicine, scientific research, agriculture and industry, and occupations which involve exposure to enhanced levels of naturally occurring radionuclides. In 1987 the IAEA published a Safety Guide on basic principles for occupational radiation monitoring which set forth principles and objectives of a strategy for monitoring exposures of workers. Since drafting of the present Safety Practice commenced, the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) have been issued. On the basis of the principles laid down in the BSS, the 1987 Safety Guide is also being revised, and recommendations on the assessment of the occupational intake of radioactive materials are to be added. The present Safety Practice, which deals with direct measurement of radionuclides in the human body, is the first to be published in this area. Refs, figs, tabs

  19. Wearable Gaze Trackers: Mapping Visual Attention in 3D

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Stets, Jonathan Dyssel; Suurmets, Seidi

    2017-01-01

    gaze trackers allows respondents to move freely in any real world 3D environment, removing the previous restrictions. In this paper we propose a novel approach for processing visual attention of respondents using mobile wearable gaze trackers in a 3D environment. The pipeline consists of 3 steps...

  20. Gaze Shift as an Interactional Resource for Very Young Children

    Science.gov (United States)

    Kidwell, Mardi

    2009-01-01

    This article examines how very young children in a day care center make use of their peers' gaze shifts to differentially locate and prepare for the possibility of a caregiver intervention during situations of their biting, hitting, pushing, and the like. At issue is how the visible character of a gaze shift--that is, the manner in which it is…

  1. "I would like to get close to you": Making robot personal space invasion less intrusive with a social gaze cue

    DEFF Research Database (Denmark)

    Suvei, Stefan-Daniel; Vroon, Jered; Somoza Sanchez, Vella Veronica

    2018-01-01

    participants (n=83), with/without personal space invasion, and with/without a social gaze cue. With a questionnaire, we measured subjective perception of warmth, competence, and comfort after such an interaction. In addition, we used on-board sensors and a tracking system to measure the dynamics of social......How can a social robot get physically close to the people it needs to interact with? We investigated the effect of a social gaze cue by a human-sized mobile robot on the effects of personal space invasion by that robot. In our 2x2 between-subject experiment, our robot would approach our...

  2. A multimodal interface to resolve the Midas-Touch problem in gaze controlled wheelchair.

    Science.gov (United States)

    Meena, Yogesh Kumar; Cecotti, Hubert; Wong-Lin, KongFatt; Prasad, Girijesh

    2017-07-01

    Human-computer interaction (HCI) research has been playing an essential role in the field of rehabilitation. The usability of the gaze controlled powered wheelchair is limited due to Midas-Touch problem. In this work, we propose a multimodal graphical user interface (GUI) to control a powered wheelchair that aims to help upper-limb mobility impaired people in daily living activities. The GUI was designed to include a portable and low-cost eye-tracker and a soft-switch wherein the wheelchair can be controlled in three different ways: 1) with a touchpad 2) with an eye-tracker only, and 3) eye-tracker with soft-switch. The interface includes nine different commands (eight directions and stop) and integrated within a powered wheelchair system. We evaluated the performance of the multimodal interface in terms of lap-completion time, the number of commands, and the information transfer rate (ITR) with eight healthy participants. The analysis of the results showed that the eye-tracker with soft-switch provides superior performance with an ITR of 37.77 bits/min among the three different conditions (pusers.

  3. Looking into the future: An inward bias in aesthetic experience driven only by gaze cues.

    Science.gov (United States)

    Chen, Yi-Chia; Colombatto, Clara; Scholl, Brian J

    2018-07-01

    The inward bias is an especially powerful principle of aesthetic experience: In framed images (e.g. photographs), we prefer peripheral figures that face inward (vs. outward). Why does this bias exist? Since agents tend to act in the direction in which they are facing, one intriguing possibility is that the inward bias reflects a preference to view scenes from a perspective that will allow us to witness those predicted future actions. This account has been difficult to test with previous displays, in which facing direction is often confounded with either global shape profiles or the relative locations of salient features (since e.g. someone's face is generally more visually interesting than the back of their head). But here we demonstrate a robust inward bias in aesthetic judgment driven by a cue that is socially powerful but visually subtle: averted gaze. Subjects adjusted the positions of people in images to maximize the images' aesthetic appeal. People with direct gaze were not placed preferentially in particular regions, but people with averted gaze were reliably placed so that they appeared to be looking inward. This demonstrates that the inward bias can arise from visually subtle features, when those features signal how future events may unfold. Copyright © 2018. Published by Elsevier B.V.

  4. Eye gaze performance for children with severe physical impairments using gaze-based assistive technology-A longitudinal study.

    Science.gov (United States)

    Borgestig, Maria; Sandqvist, Jan; Parsons, Richard; Falkmer, Torbjörn; Hemmingsson, Helena

    2016-01-01

    Gaze-based assistive technology (gaze-based AT) has the potential to provide children affected by severe physical impairments with opportunities for communication and activities. This study aimed to examine changes in eye gaze performance over time (time on task and accuracy) in children with severe physical impairments, without speaking ability, using gaze-based AT. A longitudinal study with a before and after design was conducted on 10 children (aged 1-15 years) with severe physical impairments, who were beginners to gaze-based AT at baseline. Thereafter, all children used the gaze-based AT in daily activities over the course of the study. Compass computer software was used to measure time on task and accuracy with eye selection of targets on screen, and tests were performed with the children at baseline, after 5 months, 9-11 months, and after 15-20 months. Findings showed that the children improved in time on task after 5 months and became more accurate in selecting targets after 15-20 months. This study indicates that these children with severe physical impairments, who were unable to speak, could improve in eye gaze performance. However, the children needed time to practice on a long-term basis to acquire skills needed to develop fast and accurate eye gaze performance.

  5. Attention and Social Cognition in Virtual Reality : The effect of engagement mode and character eye-gaze

    NARCIS (Netherlands)

    Rooney, Brendan; Bálint, Katalin; Parsons, Thomas; Burke, Colin; O'Leary, T; Lee, C.T.; Mantei, C.

    2017-01-01

    Technical developments in virtual humans are manifest in modern character design. Specifically, eye gaze offers a significant aspect of such design. There is need to consider the contribution of participant control of engagement. In the current study, we manipulated participants’ engagement with an

  6. Interacting with target tracking algorithms in a gaze-enhanced motion video analysis system

    Science.gov (United States)

    Hild, Jutta; Krüger, Wolfgang; Heinze, Norbert; Peinsipp-Byma, Elisabeth; Beyerer, Jürgen

    2016-05-01

    Motion video analysis is a challenging task, particularly if real-time analysis is required. It is therefore an important issue how to provide suitable assistance for the human operator. Given that the use of customized video analysis systems is more and more established, one supporting measure is to provide system functions which perform subtasks of the analysis. Recent progress in the development of automated image exploitation algorithms allow, e.g., real-time moving target tracking. Another supporting measure is to provide a user interface which strives to reduce the perceptual, cognitive and motor load of the human operator for example by incorporating the operator's visual focus of attention. A gaze-enhanced user interface is able to help here. This work extends prior work on automated target recognition, segmentation, and tracking algorithms as well as about the benefits of a gaze-enhanced user interface for interaction with moving targets. We also propose a prototypical system design aiming to combine both the qualities of the human observer's perception and the automated algorithms in order to improve the overall performance of a real-time video analysis system. In this contribution, we address two novel issues analyzing gaze-based interaction with target tracking algorithms. The first issue extends the gaze-based triggering of a target tracking process, e.g., investigating how to best relaunch in the case of track loss. The second issue addresses the initialization of tracking algorithms without motion segmentation where the operator has to provide the system with the object's image region in order to start the tracking algorithm.

  7. Model-based acquisition and analysis of multimodal interactions for improving human-robot interaction

    OpenAIRE

    Renner, Patrick; Pfeiffer, Thies

    2014-01-01

    For solving complex tasks cooperatively in close interaction with robots, they need to understand natural human communication. To achieve this, robots could benefit from a deeper understanding of the processes that humans use for successful communication. Such skills can be studied by investigating human face-to-face interactions in complex tasks. In our work the focus lies on shared-space interactions in a path planning task and thus 3D gaze directions and hand movements are of particular in...

  8. Adaptive gaze stabilization through cerebellar internal models in a humanoid robot

    DEFF Research Database (Denmark)

    Vannucci, Lorenzo; Tolu, Silvia; Falotico, Egidio

    2016-01-01

    Two main classes of reflexes relying on the vestibular system are involved in the stabilization of the human gaze: The vestibulocollic reflex (VCR), which stabilizes the head in space and the vestibulo-ocular reflex (VOR), which stabilizes the visual axis to minimize retinal image motion. The VOR...... on the coordination of VCR and VOR and OKR. The model, inspired on neuroscientific cerebellar theories, is provided with learning and adaptation capabilities based on internal models. Tests on a simulated humanoid platform confirm the effectiveness of our approach....... works in conjunction with the opto-kinetic reflex (OKR), which is a visual feedback mechanism for moving the eye at the same speed as the observed scene. Together they keep the image stationary on the retina. In this work we present the first complete model of gaze stabilization based...

  9. Electronic medical records in diabetes consultations: participants' gaze as an interactional resource.

    Science.gov (United States)

    Rhodes, Penny; Small, Neil; Rowley, Emma; Langdon, Mark; Ariss, Steven; Wright, John

    2008-09-01

    Two routine consultations in primary care diabetes clinics are compared using extracts from video recordings of interactions between nurses and patients. The consultations were chosen to present different styles of interaction, in which the nurse's gaze was either primarily toward the computer screen or directed more toward the patient. Using conversation analysis, the ways in which nurses shift both gaze and body orientation between the computer screen and patient to influence the style, pace, content, and structure of the consultation were investigated. By examining the effects of different levels of engagement between the electronic medical record and the embodied patient in the consultation room, we argue for the need to consider the contingent nature of the interface of technology and the person in the consultation. Policy initiatives designed to deliver what is considered best-evidenced practice are modified in the micro context of the interactions of the consultation.

  10. 3D gaze tracking system for NVidia 3D Vision®.

    Science.gov (United States)

    Wibirama, Sunu; Hamamoto, Kazuhiko

    2013-01-01

    Inappropriate parallax setting in stereoscopic content generally causes visual fatigue and visual discomfort. To optimize three dimensional (3D) effects in stereoscopic content by taking into account health issue, understanding how user gazes at 3D direction in virtual space is currently an important research topic. In this paper, we report the study of developing a novel 3D gaze tracking system for Nvidia 3D Vision(®) to be used in desktop stereoscopic display. We suggest an optimized geometric method to accurately measure the position of virtual 3D object. Our experimental result shows that the proposed system achieved better accuracy compared to conventional geometric method by average errors 0.83 cm, 0.87 cm, and 1.06 cm in X, Y, and Z dimensions, respectively.

  11. Facing death, gazing inward: end-of-life and the transformation of clinical subjectivity in Thailand.

    Science.gov (United States)

    Stonington, Scott

    2011-06-01

    In this article, I describe a new form of clinical subjectivity in Thailand, emerging out of public debate over medical care at the end of life. Following the controversial high-tech death of the famous Buddhist monk Buddhadasa, many began to denounce modern death as falling prey to social ills in Thai society, such as consumerism, technology-worship, and the desire to escape the realities of existence. As a result, governmental and non-governmental organizations have begun to focus on the end-of-life as a locus for transforming Thai society. Moving beyond the classic outward focus of the medical gaze, they have begun teaching clinicians and patients to gaze inward instead, to use the suffering inherent in medicine and illness to face the nature of existence and attain inner wisdom. In this article, I describe the emergence of this new gaze and its major conceptual components, including a novel idea of what it means to be 'human,' as well as a series of technologies used to craft this humanity: confession, "facing suffering," and untying "knots" in the heart. I also describe how this new subjectivity has begun to change the long-stable Buddhist concept of death as taking place at a moment in time, giving way for a new concept of "end-of-life," an elongated interval to be experienced, studied, and used for inner wisdom.

  12. A 2D eye gaze estimation system with low-resolution webcam images

    Directory of Open Access Journals (Sweden)

    Kim Jin

    2011-01-01

    Full Text Available Abstract In this article, a low-cost system for 2D eye gaze estimation with low-resolution webcam images is presented. Two algorithms are proposed for this purpose, one for the eye-ball detection with stable approximate pupil-center and the other one for the eye movements' direction detection. Eyeball is detected using deformable angular integral search by minimum intensity (DAISMI algorithm. Deformable template-based 2D gaze estimation (DTBGE algorithm is employed as a noise filter for deciding the stable movement decisions. While DTBGE employs binary images, DAISMI employs gray-scale images. Right and left eye estimates are evaluated separately. DAISMI finds the stable approximate pupil-center location by calculating the mass-center of eyeball border vertices to be employed for initial deformable template alignment. DTBGE starts running with initial alignment and updates the template alignment with resulting eye movements and eyeball size frame by frame. The horizontal and vertical deviation of eye movements through eyeball size is considered as if it is directly proportional with the deviation of cursor movements in a certain screen size and resolution. The core advantage of the system is that it does not employ the real pupil-center as a reference point for gaze estimation which is more reliable against corneal reflection. Visual angle accuracy is used for the evaluation and benchmarking of the system. Effectiveness of the proposed system is presented and experimental results are shown.

  13. The head tracks and gaze predicts: how the world's best batters hit a ball.

    Directory of Open Access Journals (Sweden)

    David L Mann

    Full Text Available Hitters in fast ball-sports do not align their gaze with the ball throughout ball-flight; rather, they use predictive eye movement strategies that contribute towards their level of interceptive skill. Existing studies claim that (i baseball and cricket batters cannot track the ball because it moves too quickly to be tracked by the eyes, and that consequently (ii batters do not - and possibly cannot - watch the ball at the moment they hit it. However, to date no studies have examined the gaze of truly elite batters. We examined the eye and head movements of two of the world's best cricket batters and found both claims do not apply to these batters. Remarkably, the batters coupled the rotation of their head to the movement of the ball, ensuring the ball remained in a consistent direction relative to their head. To this end, the ball could be followed if the batters simply moved their head and kept their eyes still. Instead of doing so, we show the elite batters used distinctive eye movement strategies, usually relying on two predictive saccades to anticipate (i the location of ball-bounce, and (ii the location of bat-ball contact, ensuring they could direct their gaze towards the ball as they hit it. These specific head and eye movement strategies play important functional roles in contributing towards interceptive expertise.

  14. Face age modulates gaze following in young adults

    OpenAIRE

    Francesca Ciardo; Barbara F. M. Marino; Rossana Actis-Grosso; Angela Rossetti; Paola Ricciardelli

    2014-01-01

    Gaze-following behaviour is considered crucial for social interactions which are influenced by social similarity. We investigated whether the degree of similarity, as indicated by the perceived age of another person, can modulate gaze following. Participants of three different age-groups (18–25; 35–45; over 65) performed an eye movement (a saccade) towards an instructed target while ignoring the gaze-shift of distracters of different age-ranges (6–10; 18–25; 35–45; over 70). The results show ...

  15. Functional corticostriatal connection topographies predict goal directed behaviour in humans

    NARCIS (Netherlands)

    Marquand, A.F.; Haak, K.V.; Beckmann, C.F.

    2017-01-01

    Anatomical tracing studies in non-human primates have suggested that corticostriatal connectivity is topographically organized: nearby locations in striatum are connected with nearby locations in cortex. The topographic organization of corticostriatal connectivity is thought to underpin many

  16. The human gut microbiome: current knowledge, challenges, and future directions.

    Science.gov (United States)

    Dave, Maneesh; Higgins, Peter D; Middha, Sumit; Rioux, Kevin P

    2012-10-01

    The Human Genome Project was completed a decade ago, leaving a legacy of process, tools, and infrastructure now being turned to the study of the microbes that reside in and on the human body as determinants of health and disease, and has been branded "The Human Microbiome Project." Of the various niches under investigation, the human gut houses the most complex and abundant microbial community and is an arena for important host-microbial interactions that have both local and systemic impact. Initial studies of the human microbiome have been largely descriptive, a testing ground for innovative molecular techniques and new hypotheses. Methods for studying the microbiome have quickly evolved from low-resolution surveys of microbial community structure to high-definition description of composition, function, and ecology. Next-generation sequencing technologies combined with advanced bioinformatics place us at the doorstep of revolutionary insight into the composition, capability, and activity of the human intestinal microbiome. Renewed efforts to cultivate previously "uncultivable" microbes will be important to the overall understanding of gut ecology. There remain numerous methodological challenges to the effective study and understanding of the gut microbiome, largely relating to study design, sample collection, and the number of predictor variables. Strategic collaboration of clinicians, microbiologists, molecular biologists, computational scientists, and bioinformaticians is the ideal paradigm for success in this field. Meaningful interpretation of the gut microbiome requires that host genetic and environmental influences be controlled or accounted for. Understanding the gut microbiome in healthy humans is a foundation for discovering its influence in various important gastrointestinal and nutritional diseases (eg, inflammatory bowel disease, diabetes, and obesity), and for rational translation to human health gains. Copyright © 2012 Mosby, Inc. All rights

  17. Consciousness in humans and non-human animals: recent advances and future directions.

    Science.gov (United States)

    Boly, Melanie; Seth, Anil K; Wilke, Melanie; Ingmundson, Paul; Baars, Bernard; Laureys, Steven; Edelman, David B; Tsuchiya, Naotsugu

    2013-10-31

    This joint article reflects the authors' personal views regarding noteworthy advances in the neuroscience of consciousness in the last 10 years, and suggests what we feel may be promising future directions. It is based on a small conference at the Samoset Resort in Rockport, Maine, USA, in July of 2012, organized by the Mind Science Foundation of San Antonio, Texas. Here, we summarize recent advances in our understanding of subjectivity in humans and other animals, including empirical, applied, technical, and conceptual insights. These include the evidence for the importance of fronto-parietal connectivity and of "top-down" processes, both of which enable information to travel across distant cortical areas effectively, as well as numerous dissociations between consciousness and cognitive functions, such as attention, in humans. In addition, we describe the development of mental imagery paradigms, which made it possible to identify covert awareness in non-responsive subjects. Non-human animal consciousness research has also witnessed substantial advances on the specific role of cortical areas and higher order thalamus for consciousness, thanks to important technological enhancements. In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states. Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence. Along with reviewing these findings, each author suggests future avenues for research in their field of investigation.

  18. Modelling Virtual Camera Behaviour Through Player Gaze

    DEFF Research Database (Denmark)

    Picardi, Andrea; Burelli, Paolo; Yannakakis, Georgios N.

    2012-01-01

    industry and game AI research focus on the devel- opment of increasingly sophisticated systems to automate the control of the virtual camera integrating artificial intel- ligence algorithms within physical simulations. However, in both industry and academia little research has been carried out......In a three-dimensional virtual environment, aspects such as narrative and interaction largely depend on the placement and animation of the virtual camera. Therefore, virtual camera control plays a critical role in player experience and, thereby, in the overall quality of a computer game. Both game...... on the relationship between virtual camera, game-play and player behaviour. We run a game user experiment to shed some light on this relationship and identify relevant dif- ferences between camera behaviours through different game sessions, playing behaviours and player gaze patterns. Re- sults show that users can...

  19. Isolated Horizontal Gaze Palsy: Observations and Explanations

    Directory of Open Access Journals (Sweden)

    Renee Ewe

    2017-11-01

    Full Text Available We present three cases that we suggest require a novel diagnosis and a reconsideration of current understandings of pontine anatomy. In this case series, we highlight a series of patients with monophasic, fully recovering inflammatory lesions in the pontine tegmentum not due to any of the currently recognized causes of this syndrome. We highlight other similar cases in the literature and suggest there may be a particular epitope for an as-yet-undiscovered antibody underlying the tropism for this area. We highlight the potential harm of misdiagnosis with relapsing inflammatory or other serious diagnoses with significant adverse impact on the patient. In addition, we propose that this would support a reinterpretation of the currently accepted anatomy of the pontine gaze inputs to the median longitudinal fasciculus and paramedian pontine reticular formation.

  20. Toward understanding social cues and signals in human–robot interaction: effects of robot gaze and proxemic behavior

    Science.gov (United States)

    Fiore, Stephen M.; Wiltshire, Travis J.; Lobato, Emilio J. C.; Jentsch, Florian G.; Huang, Wesley H.; Axelrod, Benjamin

    2013-01-01

    As robots are increasingly deployed in settings requiring social interaction, research is needed to examine the social signals perceived by humans when robots display certain social cues. In this paper, we report a study designed to examine how humans interpret social cues exhibited by robots. We first provide a brief overview of perspectives from social cognition in humans and how these processes are applicable to human–robot interaction (HRI). We then discuss the need to examine the relationship between social cues and signals as a function of the degree to which a robot is perceived as a socially present agent. We describe an experiment in which social cues were manipulated on an iRobot AvaTM mobile robotics platform in a hallway navigation scenario. Cues associated with the robot’s proxemic behavior were found to significantly affect participant perceptions of the robot’s social presence and emotional state while cues associated with the robot’s gaze behavior were not found to be significant. Further, regardless of the proxemic behavior, participants attributed more social presence and emotional states to the robot over repeated interactions than when they first interacted with it. Generally, these results indicate the importance for HRI research to consider how social cues expressed by a robot can differentially affect perceptions of the robot’s mental states and intentions. The discussion focuses on implications for the design of robotic systems and future directions for research on the relationship between social cues and signals. PMID:24348434

  1. Direct detection of a single photon by humans

    Science.gov (United States)

    Tinsley, Jonathan N.; Molodtsov, Maxim I.; Prevedel, Robert; Wartmann, David; Espigulé-Pons, Jofre; Lauwers, Mattias; Vaziri, Alipasha

    2016-01-01

    Despite investigations for over 70 years, the absolute limits of human vision have remained unclear. Rod cells respond to individual photons, yet whether a single-photon incident on the eye can be perceived by a human subject has remained a fundamental open question. Here we report that humans can detect a single-photon incident on the cornea with a probability significantly above chance. This was achieved by implementing a combination of a psychophysics procedure with a quantum light source that can generate single-photon states of light. We further discover that the probability of reporting a single photon is modulated by the presence of an earlier photon, suggesting a priming process that temporarily enhances the effective gain of the visual system on the timescale of seconds. PMID:27434854

  2. Stay tuned: Inter-individual neural synchronization during mutual gaze and joint attention

    Directory of Open Access Journals (Sweden)

    Daisuke N Saito

    2010-11-01

    Full Text Available Eye contact provides a communicative link between humans, prompting joint attention. As spontaneous brain activity may have an important role in coordination of neuronal processing within the brain, their inter-subject synchronization may occur during eye contact. To test this, we conducted simultaneous functional MRI in pairs of adults. Eye contact was maintained at baseline while the subjects engaged in real-time gaze exchange in a joint attention task. Averted gaze activated the bilateral occipital pole extending to the right posterior superior temporal sulcus, the dorso-medial prefrontal cortex, and bilateral inferior frontal gyrus. Following a partner’s gaze towards an object activated the left intraparietal sulcus. After all task-related effects were modeled out, inter-individual correlation analysis of residual time-courses was performed. Paired subjects showed more prominent correlations than non-paired subjects in the right inferior frontal gyrus, suggesting that this region is involved in sharing intention during eye contact that provides the context for joint attention.

  3. Neurocognitive mechanisms of gaze-expression interactions in face processing and social attention.

    Science.gov (United States)

    Graham, Reiko; Labar, Kevin S

    2012-04-01

    The face conveys a rich source of non-verbal information used during social communication. While research has revealed how specific facial channels such as emotional expression are processed, little is known about the prioritization and integration of multiple cues in the face during dyadic exchanges. Classic models of face perception have emphasized the segregation of dynamic vs. static facial features along independent information processing pathways. Here we review recent behavioral and neuroscientific evidence suggesting that within the dynamic stream, concurrent changes in eye gaze and emotional expression can yield early independent effects on face judgments and covert shifts of visuospatial attention. These effects are partially segregated within initial visual afferent processing volleys, but are subsequently integrated in limbic regions such as the amygdala or via reentrant visual processing volleys. This spatiotemporal pattern may help to resolve otherwise perplexing discrepancies across behavioral studies of emotional influences on gaze-directed attentional cueing. Theoretical explanations of gaze-expression interactions are discussed, with special consideration of speed-of-processing (discriminability) and contextual (ambiguity) accounts. Future research in this area promises to reveal the mental chronometry of face processing and interpersonal attention, with implications for understanding how social referencing develops in infancy and is impaired in autism and other disorders of social cognition. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Strange-face Illusions During Interpersonal-Gazing and Personality Differences of Spirituality.

    Science.gov (United States)

    Caputo, Giovanni B

    Strange-face illusions are produced when two individuals gaze at each other in the eyes in low illumination for more than a few minutes. Usually, the members of the dyad perceive numinous apparitions, like the other's face deformations and perception of a stranger or a monster in place of the other, and feel a short lasting dissociation. In the present experiment, the influence of the spirituality personality trait on strength and number of strange-face illusions was investigated. Thirty participants were preliminarily tested for superstition (Paranormal Belief Scale, PBS) and spirituality (Spiritual Transcendence Scale, STS); then, they were randomly assigned to 15 dyads. Dyads performed the intersubjective gazing task for 10 minutes and, finally, strange-face illusions (measured through the Strange-Face Questionnaire, SFQ) were evaluated. The first finding was that SFQ was independent of PBS; hence, strange-face illusions during intersubjective gazing are authentically perceptual, hallucination-like phenomena, and not due to superstition. The second finding was that SFQ depended on the spiritual-universality scale of STS (a belief in the unitive nature of life; e.g., "there is a higher plane of consciousness or spirituality that binds all people") and the two variables were negatively correlated. Thus, strange-face illusions, in particular monstrous apparitions, could potentially disrupt binding among human beings. Strange-face illusions can be considered as 'projections' of the subject's unconscious into the other's face. In conclusion, intersubjective gazing at low illumination can be a tool for conscious integration of unconscious 'shadows of the Self' in order to reach completeness of the Self. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. The Benslimane's Artistic Model for Females' Gaze Beauty: An Original Assessment Tool.

    Science.gov (United States)

    Benslimane, Fahd; van Harpen, Laura; Myers, Simon R; Ingallina, Fabio; Ghanem, Ali M

    2017-02-01

    The aim of this paper is to analyze the aesthetic characteristics of the human females' gaze using anthropometry and to present an artistic model to represent it: "The Frame Concept." In this model, the eye fissure represents a painting, and the most peripheral shadows around it represent the frame of this painting. The narrower the frame, the more aesthetically pleasing and youthful the gaze appears. This study included a literature review of the features that make the gaze appear attractive. Photographs of models with attractive gazes were examined, and old photographs of patients were compared to recent photographs. The frame ratio was defined by anthropometric measurements of modern portraits of twenty consecutive Miss World winners. The concept was then validated for age and attractiveness across centuries by analysis of modern female photographs and works of art acknowledged for portraying beautiful young and older women in classical paintings. The frame height inversely correlated with attractiveness in modern female portrait photographs. The eye fissure frame ratio of modern idealized female portraits was similar to that of beautiful female portraits idealized by classical artists. In contrast, the eye fissure frames of classical artists' mothers' portraits were significantly wider than those of beautiful younger women. The Frame Concept is a valid artistic tool that provides an understanding of both the aesthetic and aging characteristics of the female periorbital region, enabling the practitioner to plan appropriate aesthetic interventions. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the A3 online Instructions to Authors. www.springer.com/00266 .

  6. The Politics of the Gaze Foucault, Lacan and Zizek

    Directory of Open Access Journals (Sweden)

    Henry Krips

    2010-03-01

    Full Text Available Joan Copjec accuses orthodox film theory of misrepresenting the Lacanian gaze by assimilating it to Foucauldian panopticon (Copjec 1994: 18-19. Although Copjec is correct that orthodox film theory misrepresents the Lacanian gaze, she, in turn, misrepresents Foucault by choosing to focus exclusively upon those as-pects of his work on the panopticon that have been taken up by orthodox film the-ory (Copjec 1994: 4. In so doing, I argue, Copjec misses key parallels between the Lacanian and Foucauldian concepts of the gaze. More than a narrow academic dispute about how to read Foucault and Lacan, this debate has wider political sig-nificance. In particular, using Slavoj Zizek's work, I show that a correct account of the panoptic gaze leads us to rethink the question of how to oppose modern techniques of surveillance.

  7. The Rethorics of Gaze in Luhrmann's "Postmodern Great Gatsby"

    Directory of Open Access Journals (Sweden)

    Paola Fallerini

    2014-05-01

    Adopting the perspective suggested by the rhetoric of the gaze (Laura Mulvey it is highlighted the metalinguistic and metatextual reflection through which this movie contributes to the critical interpretation of Fitzgerald’s novel.

  8. WOMAN AS OBJECT OF MALE GAZE IN SOME WORKS OF ...

    African Journals Online (AJOL)

    Nkiruka

    marketing and sale of the product, but also an object of male gaze. ... Edward Manet, whose painting Olympia, thought to be inspired by Titian‟s ... encountered in Western art history, whereas unidentifiable nude males were infrequently.

  9. Latvian government in double jeopardy with EU, Latvijas Gaze

    Index Scriptorium Estoniae

    2005-01-01

    Läti soovib saada Euroopa Komisjonilt ajapikendust gaasituru liberaliseerimiseks 2010. aastani ning lubab sel juhul sõlmida Latvijas Gaze'ga kokkuleppe, et viimane loobuks gaasitarnete ainuõigusest Lätis

  10. Design of a Binocular Pupil and Gaze Point Detection System Utilizing High Definition Images

    Directory of Open Access Journals (Sweden)

    Yilmaz Durna

    2017-05-01

    Full Text Available This study proposes a novel binocular pupil and gaze detection system utilizing a remote full high definition (full HD camera and employing LabVIEW. LabVIEW is inherently parallel and has fewer time-consuming algorithms. Many eye tracker applications are monocular and use low resolution cameras due to real-time image processing difficulties. We utilized the computer’s direct access memory channel for rapid data transmission and processed full HD images with LabVIEW. Full HD images make easier determinations of center coordinates/sizes of pupil and corneal reflection. We modified the camera so that the camera sensor passed only infrared (IR images. Glints were taken as reference points for region of interest (ROI area selection of the eye region in the face image. A morphologic filter was applied for erosion of noise, and a weighted average technique was used for center detection. To test system accuracy with 11 participants, we produced a visual stimulus set up to analyze each eye’s movement. Nonlinear mapping function was utilized for gaze estimation. Pupil size, pupil position, glint position and gaze point coordinates were obtained with free natural head movements in our system. This system also works at 2046 × 1086 resolution at 40 frames per second. It is assumed that 280 frames per second for 640 × 480 pixel images is the case. Experimental results show that the average gaze detection error for 11 participants was 0.76° for the left eye, 0.89° for right eye and 0.83° for the mean of two eyes.

  11. Direct action of endocrine disrupting chemicals on human sperm

    DEFF Research Database (Denmark)

    Schiffer, Christian; Müller, Astrid; Egeberg, Dorte L

    2014-01-01

    Synthetic endocrine disrupting chemicals (EDCs), omnipresent in food, household, and personal care products, have been implicated in adverse trends in human reproduction, including infertility and increasing demand for assisted reproduction. Here, we study the action of 96 ubiquitous EDCs on huma...

  12. Directional dominance on stature and cognition in diverse human populations

    NARCIS (Netherlands)

    Joshi, Peter K.; Esko, Tonu; Mattsson, Hannele; Eklund, Niina; Gandin, Ilaria; Nutile, Teresa; Jackson, Anne U.; Schurmann, Claudia; Smith, Albert V.; Zhang, Weihua; Okada, Yukinori; Stancakova, Alena; Faul, Jessica D.; Zhao, Wei; Bartz, Traci M.; Concas, Maria Pina; Franceschini, Nora; Enroth, Stefan; Vitart, Veronique; Trompet, Stella; Guo, Xiuqing; Chasman, Daniel I.; O'Connel, Jeffrey R.; Corre, Tanguy; Nongmaithem, Suraj S.; Chen, Yuning; Mangino, Massimo; Ruggiero, Daniela; Traglia, Michela; Farmaki, Aliki-Eleni; Kacprowski, Tim; Bjonnes, Andrew; van der Spek, Ashley; Wu, Ying; Giri, Anil K.; Yanek, Lisa R.; Wang, Lihua; Hofer, Edith; Rietveld, Cornelius A.; McLeod, Olga; Cornelis, Marilyn C.; Pattaro, Cristian; Verweij, Niek; Baumbach, Clemens; Abdellaoui, Abdel; Warren, Helen R.; Vuckovic, Dragana; Mei, Hao; Bouchard, Claude; Perry, John R. B.; Cappellani, Stefania; Mirza, Saira S.; Benton, Miles C.; Broeckel, Ulrich; Medland, Sarah E.; Lind, PenelopeA.; Malerba, Giovanni; Drong, Alexander; Yengo, Loic; Bielak, Lawrence F.; Zhi, Degui; van der Most, Peter J.; Shriner, Daniel; Maegi, Reedik; Hemani, Gibran; Karaderi, Tugce; Wang, Zhaoming; Liu, Tian; Demuth, Ilja; Zhao, Jing Hua; Meng, Weihua; Lataniotis, Lazaros; van der Laan, Sander W.; Bradfield, Jonathan P.; Wood, Andrew R.; Bonnefond, Amelie; Ahluwalia, Tarunveer S.; Hall, LeanneM.; Salvi, Erika; Yazar, Seyhan; Carstensen, Lisbeth; de Haan, Hugoline G.; Abney, Mark; Afzal, Uzma; Allison, Matthew A.; Amin, Najaf; Asselbergs, Folkert W.; Bakker, Stephan J. L.; Barr, R. Graham; Baumeister, Sebastian E.; Benjamin, Daniel J.; Bergmann, Sven; Boerwinkle, Eric; Bottinger, Erwin P.; Campbell, Archie; Chakravarti, Aravinda; Chan, Yingleong; Chanock, Stephen J.; Chen, Constance; Chen, Y. -D. Ida; Collins, Francis S.; Connell, John; Correa, Adolfo; Cupples, L. Adrienne; Smith, George Davey; Davies, Gail; Doerr, Marcus; Ehret, Georg; Ellis, Stephen B.; Feenstra, Bjarke; Feitosa, Mary F.; Ford, Ian; Fox, Caroline S.; Frayling, Timothy M.; Friedrich, Nele; Geller, Frank; Scotland, Generation; Gillham-Nasenya, Irina; Gottesman, Omri; Graff, Misa; Grodstein, Francine; Gu, Charles; Haley, Chris; Hammond, Christopher J.; Harris, Sarah E.; Harris, Tamara B.; Hastie, Nicholas D.; Heard-Costa, Nancy L.; Heikkila, Kauko; Hocking, Lynne J.; Homuth, Georg; Hottenga, Jouke-Jan; Huang, Jinyan; Huffman, Jennifer E.; Hysi, Pirro G.; Ikram, M. Arfan; Ingelsson, Erik; Joensuu, Anni; Johansson, Asa; Jousilahti, Pekka; Jukema, J. Wouter; Kahonen, Mika; Kamatani, Yoichiro; Kanoni, Stavroula; Kerr, Shona M.; Khan, Nazir M.; Koellinger, Philipp; Koistinen, Heikki A.; Kooner, Manraj K.; Kubo, Michiaki; Kuusisto, Johanna; Lahti, Jari; Launer, Lenore J.; Lea, Rodney A.; Lehne, Benjamin; Lehtimaki, Terho; Liewald, David C. M.; Lind, Lars; Loh, Marie; Lokki, Marja-Liisa; London, Stephanie J.; Loomis, Stephanie J.; Loukola, Anu; Lu, Yingchang; Lumley, Thomas; Lundqvist, Annamari; Mannisto, Satu; Marques-Vidal, Pedro; Masciullo, Corrado; Matchan, Angela; Mathias, Rasika A.; Matsuda, Koichi; Meigs, James B.; Meisinger, Christa; Meitinger, Thomas; Menni, Cristina; Mentch, Frank D.; Mihailov, Evelin; Milani, Lili; Montasser, May E.; Montgomery, GrantW.; Morrison, Alanna; Myers, Richard H.; Nadukuru, Rajiv; Navarro, Pau; Nelis, Mari; Nieminen, Markku S.; Nolte, Ilja M.; O'Connor, George T.; Ogunniyi, Adesola; Padmanabhan, Sandosh; Palmas, Walter R.; Pankow, James S.; Patarcic, Inga; Pavani, Francesca; Peyser, Patricia A.; Pietilainen, Kirsi; Poulter, Neil; Prokopenko, Inga; Ralhan, Sarju; Redmond, Paul; Rich, Stephen S.; Rissanen, Harri; Robino, Antonietta; Rose, Lynda M.; Rose, Richard; Sala, Cinzia; Salako, Babatunde; Salomaa, Veikko; Sarin, Antti-Pekka; Saxena, Richa; Schmidt, Helena; Scott, Laura J.; Scott, William R.; Sennblad, Bengt; Seshadri, Sudha; Sever, Peter; Shrestha, Smeeta; Smith, Blair H.; Smith, Jennifer A.; Soranzo, Nicole; Sotoodehnia, Nona; Southam, Lorraine; Stanton, Alice V.; Stathopoulou, Maria G.; Strauch, Konstantin; Strawbridge, Rona J.; Suderman, Matthew J.; Tandon, Nikhil; Tang, Sian-Tsun; Taylor, Kent D.; Tayo, Bamidele O.; Toeglhofer, Anna Maria; Tomaszewski, Maciej; Tsernikova, Natalia; Tuomilehto, Jaakko; Uitterlinden, Andre G.; Vaidya, Dhananjay; Vlieg, Astrid van Hylckama; van Setten, Jessica; Vasankari, Tuula; Vedantam, Sailaja; Vlachopoulou, Efthymia; Vozzi, Diego; Vuoksimaa, Eero; Waldenberger, Melanie; Ware, Erin B.; Wentworth-Shields, William; Whitfield, John B.; Wild, Sarah; Willemsen, Gonneke; Yajnik, Chittaranjan S.; Yao, Jie; Zaza, Gianluigi; Zhu, Xiaofeng; Salem, Rany M.; Melbye, Mads; Bisgaard, Hans; Samani, Nilesh J.; Cusi, Daniele; Mackey, David A.; Cooper, Richard S.; Froguel, Philippe; Pasterkamp, Gerard; Grant, Struan F. A.; Hakonarson, Hakon; Ferrucci, Luigi; Scott, Robert A.; Morris, Andrew D.; Palmer, Colin N. A.; Dedoussis, George; Deloukas, Panos; Bertram, Lars; Lindenberger, Ulman; Berndt, Sonja I.; Lindgren, Cecilia M.; Timpson, Nicholas J.; Toenjes, Anke; Munroe, Patricia B.; Sorensen, Thorkild I. A.; Rotimi, Charles N.; Arnett, Donna K.; Oldehinkel, Albertine J.; Kardia, Sharon L. R.; Balkau, Beverley; Gambaro, Giovanni; Morris, Andrew P.; Eriksson, Johan G.; Wright, Margie J.; Martin, Nicholas G.; Hunt, Steven C.; Starr, John M.; Deary, Ian J.; Griffiths, Lyn R.; Tiemeier, Henning; Pirastu, Nicola; Kaprio, Jaakko; Wareham, Nicholas J.; Perusse, Louis; Wilson, James G.; Girotto, Giorgia; Caulfield, Mark J.; Raitakari, Olli; Boomsma, Dorret I.; Gieger, Christian; van der Harst, Pim; Hicks, Andrew A.; Kraft, Peter; Sinisalo, Juha; Knekt, Paul; Johannesson, Magnus; Magnusson, Patrik K. E.; Hamsten, Anders; Schmidt, Reinhold; Borecki, Ingrid B.; Vartiainen, Erkki; Becker, Diane M.; Bharadwaj, Dwaipayan; Mohlke, Karen L.; Boehnke, Michael; van Duijn, Cornelia M.; Sanghera, Dharambir K.; Teumer, Alexander; Zeggini, Eleftheria; Metspalu, Andres; Gasparini, Paolo; Ulivi, Sheila; Ober, Carole; Toniolo, Daniela; Rudan, Igor; Porteous, David J.; Ciullo, Marina; Spector, Tim D.; Hayward, Caroline; Dupuis, Josee; Loos, Ruth J. F.; Wright, Alan F.; Chandak, Giriraj R.; Vollenweider, Peter; Shuldiner, Alan R.; Ridker, Paul M.; Rotter, Jerome I.; Sattar, Naveed; Gyllensten, Ulf; North, Kari E.; Pirastu, Mario; Psaty, Bruce M.; Weir, David R.; Laakso, Markku; Gudnason, Vilmundur; Takahashi, Atsushi; Chambers, John C.; Kooner, Jaspal S.; Strachan, David P.; Campbell, Harry; Hirschhorn, Joel N.; Perola, Markus; Polasek, Ozren; Wilson, James F.

    2015-01-01

    Homozygosity has long been associated with rare, often devastating, Mendelian disorders(1), and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness(2). However, the effect of the more distant parental relatedness that is common in modern human populations is less

  13. Direct human impacts on the peatland carbon sink

    Science.gov (United States)

    Jukka Laine; Kari Minkkinen; Carl Trettin

    2009-01-01

    Northern peatlands occupy over 3 million km2 globally and contain the largest carbon (C) pool (typically >100 kg C m-2) among terrestrial ecosystems. Agriculture, forestry, and peat harvesting are the principal human-induced activities that alter the peatland and hence the distribution and flux of carbon. As a prerequisite to those uses, the peatland is usually...

  14. Legon at 60: New Directions for the Humanities | Oduyoye | Legon ...

    African Journals Online (AJOL)

    Legon Journal of the Humanities. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 21 (2010) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load ...

  15. Directional dominance on stature and cognition in diverse human populations

    NARCIS (Netherlands)

    P.K. Joshi (Peter); T. Esko (Tõnu); H. Mattsson (Hannele); N. Eklund (Niina); I. Gandin (Ilaria); T. Nutile; A.U. Jackson (Anne); C. Schurmann (Claudia); G.D. Smith; W. Zhang (Weihua); Y. Okada (Yukinori); A. Stancáková (Alena); J.D. Faul (Jessica D.); W. Zhao (Wei); T.M. Bartz (Traci M.); M.P. Concas (Maria Pina); N. Franceschini (Nora); S. Enroth (Stefan); V. Vitart (Veronique); S. Trompet (Stella); X. Guo (Xiuqing); D.I. Chasman (Daniel); J.R. O'Connel (Jeffrey R.); T. Corre (Tanguy); S.S. Nongmaithem (Suraj S.); Y. Chen (Yuning); M. Mangino (Massimo); D. Ruggiero; M. Traglia (Michela); A.-E. Farmaki (Aliki-Eleni); T. Kacprowski (Tim); A. Bjonnes (Andrew); A. van der Spek (Ashley); Y. Wu (Ying); A.K. Giri (Anil K.); L.R. Yanek (Lisa); L. Wang (Lihua); E. Hofer (Edith); C.A. Rietveld (Niels); O. McLeod (Olga); M. Cornelis (Marilyn); C. Pattaro (Cristian); N. Verweij (Niek); C. Baumbach (Clemens); A. Abdellaoui (Abdel); H. Warren (Helen); D. Vuckovic (Dragana); H. Mei (Hao); C. Bouchard (Claude); J.R.B. Perry (John); S. Cappellani (Stefania); S.S. Mirza (Saira); M.C. Benton (Miles C.); U. Broeckel (Ulrich); S.E. Medland (Sarah Elizabeth); P.A. Lind (Penelope); G. Malerba (Giovanni); A. Drong (Alexander); L. Yengo (Loic); L.F. Bielak (Lawrence F.); D. Zhi (Degui); P.J. van der Most (Peter); D. Shriner (Daniel); R. Mägi (Reedik); G. Hemani; T. Karaderi (Tugce); Z. Wang (Zhaoming); T. Liu (Tian); I. Demuth (Ilja); J.H. Zhao (Jing Hua); W. Meng (Weihua); L. Lataniotis (Lazaros); S.W. Van Der Laan (Sander W.); J.P. Bradfield (Jonathan); A.R. Wood (Andrew); A. Bonnefond (Amélie); T.S. Ahluwalia (Tarunveer Singh); L.M. Hall (Leanne M.); E. Salvi (Erika); S. Yazar (Seyhan); L. Carstensen (Lisbeth); H.G. De Haan (Hugoline G.); M. Abney (Mark); U. Afzal (Uzma); M.A. Allison (Matthew); N. Amin (Najaf); F.W. Asselbergs (Folkert W.); S.J.L. Bakker (Stephan); R.G. Barr (Graham); S.E. Baumeister (Sebastian); D.J. Benjamin (Daniel J.); S. Bergmann (Sven); E.A. Boerwinkle (Eric); E.P. Bottinger (Erwin P.); A. Campbell (Archie); A. Chakravarti (Aravinda); Y. Chan (Yingleong); S.J. Chanock (Stephen); C. Chen (Constance); Y.-D.I. Chen (Y.-D. Ida); F.S. Collins (Francis); J. Connell (John); A. Correa (Adolfo); L.A. Cupples (Adrienne); G.D. Smith; G. Davies (Gail); M. Dörr (Marcus); G.B. Ehret (Georg); S.B. Ellis (Stephen B.); B. Feenstra (Bjarke); M.F. Feitosa (Mary Furlan); I. Ford; C.S. Fox (Caroline); T.M. Frayling (Timothy); N. Friedrich (Nele); F. Geller (Frank); G. Scotland (Generation); I. Gillham-Nasenya (Irina); R.F. Gottesman (Rebecca); M.J. Graff (Maud J.L.); F. Grodstein (Francine); C. Gu (Charles); C. Haley (Chris); C.J. Hammond (Christopher); S.E. Harris (Sarah); T.B. Harris (Tamara); N. Hastie (Nick); N.L. Heard-Costa (Nancy); K. Heikkilä (Kauko); L.J. Hocking (Lynne); G. Homuth (Georg); J.J. Hottenga (Jouke Jan); J. Huang (Jian); J.E. Huffman (Jennifer); P.G. Hysi (Pirro); M.A. Ikram (Arfan); E. Ingelsson (Erik); A. Joensuu (Anni); A. Johansson (Åsa); P. Jousilahti (Pekka); J.W. Jukema (Jan Wouter); M. Kähönen (Mika); Y. Kamatani (Yoichiro); S. Kanoni (Stavroula); S.M. Kerr (Shona); N.M. Khan (Nazir M.); Ph.D. Koellinger (Philipp); H.A. Koistinen (Heikki A.); M.K. Kooner (Manraj K.); M. Kubo (Michiaki); J. Kuusisto (Johanna); J. Lahti (Jari); L.J. Launer (Lenore); R.A. Lea (Rodney A.); B. Lehne (Benjamin); T. Lehtimäki (Terho); D.C. Liewald (David C.); L. Lind (Lars); M. Loh (Marie); M.L. Lokki; S.J. London (Stephanie J.); S.J. Loomis (Stephanie J.); A. Loukola (Anu); Y. Lu (Yingchang); T. Lumley (Thomas); A. Lundqvist (Annamari); S. Männistö (Satu); P. Marques-Vidal (Pedro); C. Masciullo (Corrado); A. Matchan (Angela); J. Mathias (Jasmine); K. Matsuda (Koichi); J.B. Meigs (James); C. Meisinger (Christa); T. Meitinger (Thomas); C. Menni (Cristina); F.D. Mentch (Frank); E. Mihailov (Evelin); L. Milani (Lili); M.E. Montasser (May E.); G.W. Montgomery (Grant); A.C. Morrison (Alanna); R.H. Myers (Richard); R. Nadukuru (Rajiv); P. Navarro (Pau); M. Nalis (Mari); M.S. Nieminen (Markku S.); I.M. Nolte (Ilja M.); G.T. O'Connor (George); A. Ogunniyi (Adesola); S. Padmanabhan (Sandosh); W. Palmas (Walter); J.S. Pankow (James); I. Patarcic (Inga); F. Pavani (Francesca); P.A. Peyser (Patricia A.); K.H. Pietilainen (Kirsi Hannele); N.R. Poulter (Neil); I. Prokopenko (Inga); S. Ralhan (Sarju); P. Redmond (Paul); S.S. Rich (Stephen S.); H. Rissanen (Harri); A. Robino (Antonietta); L.M. Rose (Lynda M.); R.J. Rose (Richard J.); C. Sala (Cinzia); B. Salako (Babatunde); V. Salomaa (Veikko); A.-P. Sarin; R. Saxena (Richa); R. Schmidt (Reinhold); L.J. Scott (Laura); W.R. Scott (William R.); B. Sennblad (Bengt); S. Seshadri (Sudha); P. Sever (Peter); S. Shrestha (Smeeta); B.H. Smith (Blair); J.A. Smith (Jennifer A); N. Soranzo (Nicole); N. Sotoodehnia (Nona); L. Southam (Lorraine); A. Stanton (Alice); M.G. Stathopoulou (Maria G); K. Strauch (Konstantin); R.J. Strawbridge (Rona); M.J. Suderman (Matthew J.); N. Tandon (Nikhil); S.-T. Tang (Sian-Tsun); K.D. Taylor (Kent D.); B. Tayo (Bamidele); A.M. Töglhofer (Anna Maria); M. Tomaszewski (Maciej); N. Tsernikova (Natalia); J. Tuomilehto (Jaakko); A.G. Uitterlinden (André); D. Vaidya (Dhananjay); A. van Hylckama Vlieg (Astrid); J. van Setten (Jessica); T. Vasankari (Tuula); S. Vedantam (Sailaja); E. Vlachopoulou (Efthymia); D. Vozzi (Diego); E. Vuoksimaa (Eero); M. Waldenberger (Melanie); E.B. Ware (Erin B.); W. Wentworth-Shields (William); J. Whitfield (John); S. Wild (Sarah); G.A.H.M. Willemsen (Gonneke); C.S. Yajnik (Chittaranjan S.); J. Yao (Jie); G. Zaza (Gianluigi); X. Zhu (Xiaofeng); R.M. Salem (Rany); M. Melbye (Mads); H. Bisgaard (Hans); N.J. Samani (Nilesh); D. Cusi (Daniele); D.A. Mackey (David A.); R.S. Cooper (Richard S.); P. Froguel (Philippe); G. Pasterkamp (Gerard); S.F.A. Grant (Struan F.A.); H. Hakonarson (Hakon); L. Ferrucci (Luigi); R.A. Scott (Robert); A.D. Morris (Andrew); C.N.A. Palmer (Colin); G.V. Dedoussis (George V.); P. Deloukas (Panagiotis); L. Bertram (Lars); U. Lindenberger (Ulman); S.I. Berndt (Sonja); C.M. Lindgren (Cecilia); N.J. Timpson (Nicholas); A. Tönjes (Anke); P. Munroe (Patricia); T.I.A. Sørensen (Thorkild I.A.); C. Rotimi (Charles); D.K. Arnett (Donna); A.J. Oldehinkel (Albertine); S.L.R. Kardia (Sharon); B. Balkau (Beverley); G. Gambaro (Giovanni); A.P. Morris (Andrew); J.G. Eriksson (Johan G.); M.J. Wright (Margaret); N.G. Martin (Nicholas); S.C. Hunt (Steven); J.M. Starr (John); I.J. Deary (Ian J.); L.R. Griffiths (Lyn R.); H.W. Tiemeier (Henning); N. Pirastu (Nicola); J. Kaprio (Jaakko); N.J. Wareham (Nick); L. Perusse (Louis); J.G. Wilson (James); S. Girotto; M. Caulfield (Mark); O.T. Raitakari (Olli T.); D.I. Boomsma (Dorret); C. Gieger (Christian); P. van der Harst; A.A. Hicks (Andrew); P. Kraft (Peter); J. Sinisalo (Juha); P. Knekt; M. Johannesson (Magnus); P.K.E. Magnusson (Patrik K. E.); A. Hamsten (Anders); R. Schmidt (Reinhold); I.B. Borecki (Ingrid); E. Vartiainen (Erkki); D.M. Becker (Diane); D. Bharadwaj (Dwaipayan); K.L. Mohlke (Karen); M. Boehnke (Michael); C.M. van Duijn (Cornelia); D.K. Sanghera (Dharambir); A. Teumer (Alexander); E. Zeggini (Eleftheria); A. Metspalu (Andres); P. Gasparini (Paolo); S. Ulivi (Shelia); C. Ober (Carole); D. Toniolo (Daniela); I. Rudan (Igor); D.J. Porteous (David J.); M. Ciullo; T.D. Spector (Timothy); C. Hayward (Caroline); J. Dupuis (Josée); R.J.F. Loos (Ruth); A. Wright (Alan); G.R. Chandak (Giriraj); P. Vollenweider (Peter); A.R. Shuldiner (Alan); P.M. Ridker (Paul); J.I. Rotter (Jerome I.); N. Sattar (Naveed); U. Gyllensten (Ulf); K.E. North (Kari); M. Pirastu (Mario); B.M. Psaty (Bruce); D.R. Weir (David); M. Laakso (Markku); V. Gudnason (Vilmundur); A. Takahashi (Atsushi); J.C. Chambers (John C.); J.S. Kooner (Jaspal S.); D.P. Strachan (David P.); H. Campbell (Harry); J.N. Hirschhorn (Joel N.); M. Perola (Markus); O. Polasek (Ozren); J.F. Wilson (James)

    2015-01-01

    textabstractHomozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is

  16. The sensation of the look: The gazes in Laurence Anyways

    OpenAIRE

    Schultz, Corey Kai Nelson

    2018-01-01

    This article analyses the gazes, looks, stares and glares in Laurence Anyways (Xavier Dolan, 2012), and examines their affective, interpretive, and symbolic qualities, and their potential to create viewer empathy through affect. The cinematic gaze can produce sensations of shame and fear, by offering a sequence of varied “encounters” to which viewers can react, before we have been given a character onto which we can deflect them, thus bypassing the representational, narrative and even the sym...

  17. Segmentation of object-based video of gaze communication

    DEFF Research Database (Denmark)

    Aghito, Shankar Manuel; Stegmann, Mikkel Bille; Forchhammer, Søren

    2005-01-01

    Aspects of video communication based on gaze interaction are considered. The overall idea is to use gaze interaction to control video, e.g. for video conferencing. Towards this goal, animation of a facial mask is demonstrated. The animation is based on images using Active Appearance Models (AAM......). Good quality reproduction of (low-resolution) coded video of an animated facial mask as low as 10-20 kbit/s using MPEG-4 object based video is demonstated....

  18. Directed Differentiation of Human Pluripotent Stem Cells to Microglia

    Directory of Open Access Journals (Sweden)

    Panagiotis Douvaras

    2017-06-01

    Full Text Available Microglia, the immune cells of the brain, are crucial to proper development and maintenance of the CNS, and their involvement in numerous neurological disorders is increasingly being recognized. To improve our understanding of human microglial biology, we devised a chemically defined protocol to generate human microglia from pluripotent stem cells. Myeloid progenitors expressing CD14/CX3CR1 were generated within 30 days of differentiation from both embryonic and induced pluripotent stem cells (iPSCs. Further differentiation of the progenitors resulted in ramified microglia with highly motile processes, expressing typical microglial markers. Analyses of gene expression and cytokine release showed close similarities between iPSC-derived (iPSC-MG and human primary microglia as well as clear distinctions from macrophages. iPSC-MG were able to phagocytose and responded to ADP by producing intracellular Ca2+ transients, whereas macrophages lacked such response. The differentiation protocol was highly reproducible across several pluripotent stem cell lines.

  19. Direct Fusion Drive for a Human Mars Orbital Mission

    Energy Technology Data Exchange (ETDEWEB)

    Paluszek, Michael [Princeton Satellite Systems; Pajer, Gary [Princeton Satellite Systems; Razin, Yosef [Princeton Satellite Systems; Slonaker, James [Princeton Satellite Systems; Cohen, Samuel [PPPL; Feder, Russ [PPPL; Griffin, Kevin [Princeton University; Walsh, Matthew [Princeton University

    2014-08-01

    The Direct Fusion Drive (DFD) is a nuclear fusion engine that produces both thrust and electric power. It employs a field reversed configuration with an odd-parity rotating magnetic field heating system to heat the plasma to fusion temperatures. The engine uses deuterium and helium-3 as fuel and additional deuterium that is heated in the scrape-off layer for thrust augmentation. In this way variable exhaust velocity and thrust is obtained.

  20. Dog Breed Differences in Visual Communication with Humans.

    Science.gov (United States)

    Konno, Akitsugu; Romero, Teresa; Inoue-Murayama, Miho; Saito, Atsuko; Hasegawa, Toshikazu

    2016-01-01

    Domestic dogs (Canis familiaris) have developed a close relationship with humans through the process of domestication. In human-dog interactions, eye contact is a key element of relationship initiation and maintenance. Previous studies have suggested that canine ability to produce human-directed communicative signals is influenced by domestication history, from wolves to dogs, as well as by recent breed selection for particular working purposes. To test the genetic basis for such abilities in purebred dogs, we examined gazing behavior towards humans using two types of behavioral experiments: the 'visual contact task' and the 'unsolvable task'. A total of 125 dogs participated in the study. Based on the genetic relatedness among breeds subjects were classified into five breed groups: Ancient, Herding, Hunting, Retriever-Mastiff and Working). We found that it took longer time for Ancient breeds to make an eye-contact with humans, and that they gazed at humans for shorter periods of time than any other breed group in the unsolvable situation. Our findings suggest that spontaneous gaze behavior towards humans is associated with genetic similarity to wolves rather than with recent selective pressure to create particular working breeds.

  1. See You See Me: the Role of Eye Contact in Multimodal Human-Robot Interaction.

    Science.gov (United States)

    Xu, Tian Linger; Zhang, Hui; Yu, Chen

    2016-05-01

    We focus on a fundamental looking behavior in human-robot interactions - gazing at each other's face. Eye contact and mutual gaze between two social partners are critical in smooth human-human interactions. Therefore, investigating at what moments and in what ways a robot should look at a human user's face as a response to the human's gaze behavior is an important topic. Toward this goal, we developed a gaze-contingent human-robot interaction system, which relied on momentary gaze behaviors from a human user to control an interacting robot in real time. Using this system, we conducted an experiment in which human participants interacted with the robot in a joint attention task. In the experiment, we systematically manipulated the robot's gaze toward the human partner's face in real time and then analyzed the human's gaze behavior as a response to the robot's gaze behavior. We found that more face looks from the robot led to more look-backs (to the robot's face) from human participants and consequently created more mutual gaze and eye contact between the two. Moreover, participants demonstrated more coordinated and synchronized multimodal behaviors between speech and gaze when more eye contact was successfully established and maintained.

  2. Postural control and head stability during natural gaze behaviour in 6- to 12-year-old children.

    Science.gov (United States)

    Schärli, A M; van de Langenberg, R; Murer, K; Müller, R M

    2013-06-01

    We investigated how the influence of natural exploratory gaze behaviour on postural control develops from childhood into adulthood. In a cross-sectional design, we compared four age groups: 6-, 9-, 12-year-olds and young adults. Two experimental trials were performed: quiet stance with a fixed gaze (fixed) and quiet stance with natural exploratory gaze behaviour (exploratory). The latter was elicited by having participants watch an animated short film on a large screen in front of them. 3D head rotations in space and centre of pressure (COP) excursions on the ground plane were measured. Across conditions, both head rotation and COP displacement decreased with increasing age. Head movement was greater in the exploratory condition in all age groups. In all children-but not in adults-COP displacement was markedly greater in the exploratory condition. Bivariate correlations across groups showed highly significant positive correlations between COP displacement in ML direction and head rotation in yaw, roll, and pitch in both conditions. The regularity of COP displacements did not show a clear developmental trend, which indicates that COP dynamics were qualitatively similar across age groups. Together, the results suggest that the contribution of head movement to eye-head saccades decreases with age and that head instability-in part resulting from such gaze-related head movements-is an important limiting factor in children's postural control. The lack of head stabilisation might particularly affect children in everyday activities in which both postural control and visual exploration are required.

  3. Perceptual Training in Beach Volleyball Defence: Different Effects of Gaze-Path Cueing on Gaze and Decision-Making

    Directory of Open Access Journals (Sweden)

    André eKlostermann

    2015-12-01

    Full Text Available For perceptual-cognitive skill training, a variety of intervention methods has been proposed, including the so-called colour-cueing method which aims on superior gaze-path learning by applying visual markers. However, recent findings challenge this method, especially, with regards to its actual effects on gaze behaviour. Consequently, after a preparatory study on the identification of appropriate visual cues for life-size displays, a perceptual-training experiment on decision-making in beach volleyball was conducted, contrasting two cueing interventions (functional vs. dysfunctional gaze path with a conservative control condition (anticipation-related instructions. Gaze analyses revealed learning effects for the dysfunctional group only. Regarding decision-making, all groups showed enhanced performance with largest improvements for the control group followed by the functional and the dysfunctional group. Hence, the results confirm cueing effects on gaze behaviour, but they also question its benefit for enhancing decision-making. However, before completely denying the method’s value, optimisations should be checked regarding, for instance, cueing-pattern characteristics and gaze-related feedback.

  4. Gaze Toward Naturalistic Social Scenes by Individuals With Intellectual and Developmental Disabilities: Implications for Augmentative and Alternative Communication Designs.

    Science.gov (United States)

    Liang, Jiali; Wilkinson, Krista

    2018-04-18

    A striking characteristic of the social communication deficits in individuals with autism is atypical patterns of eye contact during social interactions. We used eye-tracking technology to evaluate how the number of human figures depicted and the presence of sharing activity between the human figures in still photographs influenced visual attention by individuals with autism, typical development, or Down syndrome. We sought to examine visual attention to the contents of visual scene displays, a growing form of augmentative and alternative communication support. Eye-tracking technology recorded point-of-gaze while participants viewed 32 photographs in which either 2 or 3 human figures were depicted. Sharing activities between these human figures are either present or absent. The sampling rate was 60 Hz; that is, the technology gathered 60 samples of gaze behavior per second, per participant. Gaze behaviors, including latency to fixate and time spent fixating, were quantified. The overall gaze behaviors were quite similar across groups, regardless of the social content depicted. However, individuals with autism were significantly slower than the other groups in latency to first view the human figures, especially when there were 3 people depicted in the photographs (as compared with 2 people). When participants' own viewing pace was considered, individuals with autism resembled those with Down syndrome. The current study supports the inclusion of social content with various numbers of human figures and sharing activities between human figures into visual scene displays, regardless of the population served. Study design and reporting practices in eye-tracking literature as it relates to autism and Down syndrome are discussed. https://doi.org/10.23641/asha.6066545.

  5. Gaze Dynamics in the Recognition of Facial Expressions of Emotion.

    Science.gov (United States)

    Barabanschikov, Vladimir A

    2015-01-01

    We studied preferably fixated parts and features of human face in the process of recognition of facial expressions of emotion. Photographs of facial expressions were used. Participants were to categorize these as basic emotions; during this process, eye movements were registered. It was found that variation in the intensity of an expression is mirrored in accuracy of emotion recognition; it was also reflected by several indices of oculomotor function: duration of inspection of certain areas of the face, its upper and bottom or right parts, right and left sides; location, number and duration of fixations, viewing trajectory. In particular, for low-intensity expressions, right side of the face was found to be attended predominantly (right-side dominance); the right-side dominance effect, was, however, absent for expressions of high intensity. For both low- and high-intensity expressions, upper face part was predominantly fixated, though with greater fixation of high-intensity expressions. The majority of trials (70%), in line with findings in previous studies, revealed a V-shaped pattern of inspection trajectory. No relationship, between accuracy of recognition of emotional expressions, was found, though, with either location and duration of fixations or pattern of gaze directedness in the face. © The Author(s) 2015.

  6. Dogs Evaluate Threatening Facial Expressions by Their Biological Validity--Evidence from Gazing Patterns.

    Directory of Open Access Journals (Sweden)

    Sanni Somppi

    Full Text Available Appropriate response to companions' emotional signals is important for all social creatures. The emotional expressions of humans and non-human animals have analogies in their form and function, suggesting shared evolutionary roots, but very little is known about how animals other than primates view and process facial expressions. In primates, threat-related facial expressions evoke exceptional viewing patterns compared with neutral or positive stimuli. Here, we explore if domestic dogs (Canis familiaris have such an attentional bias toward threatening social stimuli and whether observed emotional expressions affect dogs' gaze fixation distribution among the facial features (eyes, midface and mouth. We recorded the voluntary eye gaze of 31 domestic dogs during viewing of facial photographs of humans and dogs with three emotional expressions (threatening, pleasant and neutral. We found that dogs' gaze fixations spread systematically among facial features. The distribution of fixations was altered by the seen expression, but eyes were the most probable targets of the first fixations and gathered longer looking durations than mouth regardless of the viewed expression. The examination of the inner facial features as a whole revealed more pronounced scanning differences among expressions. This suggests that dogs do not base their perception of facial expressions on the viewing of single structures, but the interpretation of the composition formed by eyes, midface and mouth. Dogs evaluated social threat rapidly and this evaluation led to attentional bias, which was dependent on the depicted species: threatening conspecifics' faces evoked heightened attention but threatening human faces instead an avoidance response. We propose that threatening signals carrying differential biological validity are processed via distinctive neurocognitive pathways. Both of these mechanisms may have an adaptive significance for domestic dogs. The findings provide a novel

  7. Expression and site-directed mutagenesis of human dihydrofolate reductase

    Energy Technology Data Exchange (ETDEWEB)

    Prendergast, N.J.; Delcamp, T.J.; Smith, P.L.; Freisheim, J.H.

    1988-05-17

    A procaryotic high-level expression vector for human dihydrofolate reductase has been constructed and the protein characterized as a first step toward structure-function studies of this enzyme. A vector bearing the tac promoter, four synthetic oligodeoxynucleotides, and a restriction fragment from the dihydrofolate reductase cDNA were ligated in a manner which optimized the transcriptional and translational frequency of the enzyme mRNA. The reductase, comprising ca. 17% of the total soluble protein in the host bacteria, was purified to apparent homogeneity as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and characterized by amino acid composition, partial amino acid sequence, and steady-sate kinetic analysis. This expression vector has been used as a template for double-stranded plasmid DNA site-specific mutagenesis. Functional studies on a Cys-6 ..-->.. Ser-6 mutant enzyme support the contention that Cys-6 is obligatory for organomercurial activation of human dihydrofolate reductase. The Ser-6 mutant enzyme was not activated to any extent following a 24-h incubation with p-(hydroxymercuri)benzoate and nicotinamide adenine dinucleotide phosphate (reduced) (NADPH), whereas the k/sub cat/ for Cys-6 reductase increased 2-fold under identical conditions. The specific activities of the Cys-6 and Ser-6 enzymes were virtually identical as determined by methotrexate titration as were the K/sub m/ values for both dihydrofolate and NADPH. The Ser-6 mutant showed a decreased temperature stability and was more sensitive to inactivation by ..cap alpha..-chymotrypsin when compared to the wild-type enzyme. These results suggest that the Ser-6 mutant reductase is conformationally altered relative to the Cys-6 native enzyme.

  8. Expression and site-directed mutagenesis of human dihydrofolate reductase

    International Nuclear Information System (INIS)

    Prendergast, N.J.; Delcamp, T.J.; Smith, P.L.; Freisheim, J.H.

    1988-01-01

    A procaryotic high-level expression vector for human dihydrofolate reductase has been constructed and the protein characterized as a first step toward structure-function studies of this enzyme. A vector bearing the tac promoter, four synthetic oligodeoxynucleotides, and a restriction fragment from the dihydrofolate reductase cDNA were ligated in a manner which optimized the transcriptional and translational frequency of the enzyme mRNA. The reductase, comprising ca. 17% of the total soluble protein in the host bacteria, was purified to apparent homogeneity as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and characterized by amino acid composition, partial amino acid sequence, and steady-sate kinetic analysis. This expression vector has been used as a template for double-stranded plasmid DNA site-specific mutagenesis. Functional studies on a Cys-6 → Ser-6 mutant enzyme support the contention that Cys-6 is obligatory for organomercurial activation of human dihydrofolate reductase. The Ser-6 mutant enzyme was not activated to any extent following a 24-h incubation with p-(hydroxymercuri)benzoate and nicotinamide adenine dinucleotide phosphate (reduced) (NADPH), whereas the k/sub cat/ for Cys-6 reductase increased 2-fold under identical conditions. The specific activities of the Cys-6 and Ser-6 enzymes were virtually identical as determined by methotrexate titration as were the K/sub m/ values for both dihydrofolate and NADPH. The Ser-6 mutant showed a decreased temperature stability and was more sensitive to inactivation by α-chymotrypsin when compared to the wild-type enzyme. These results suggest that the Ser-6 mutant reductase is conformationally altered relative to the Cys-6 native enzyme

  9. 77 FR 14022 - Guidance for Industry: Testing for Salmonella Species in Human Foods and Direct-Human-Contact...

    Science.gov (United States)

    2012-03-08

    ...-contact animal foods, and the interpretation of test results, when the presence of Salmonella spp. in the... eggs) and direct-human-contact animal foods, and the interpretation of test results, when the presence... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2011-D-0091...

  10. Anxiety symptoms and children's eye gaze during fear learning.

    Science.gov (United States)

    Michalska, Kalina J; Machlin, Laura; Moroney, Elizabeth; Lowet, Daniel S; Hettema, John M; Roberson-Nay, Roxann; Averbeck, Bruno B; Brotman, Melissa A; Nelson, Eric E; Leibenluft, Ellen; Pine, Daniel S

    2017-11-01

    The eye region of the face is particularly relevant for decoding threat-related signals, such as fear. However, it is unclear if gaze patterns to the eyes can be influenced by fear learning. Previous studies examining gaze patterns in adults find an association between anxiety and eye gaze avoidance, although no studies to date examine how associations between anxiety symptoms and eye-viewing patterns manifest in children. The current study examined the effects of learning and trait anxiety on eye gaze using a face-based fear conditioning task developed for use in children. Participants were 82 youth from a general population sample of twins (aged 9-13 years), exhibiting a range of anxiety symptoms. Participants underwent a fear conditioning paradigm where the conditioned stimuli (CS+) were two neutral faces, one of which was randomly selected to be paired with an aversive scream. Eye tracking, physiological, and subjective data were acquired. Children and parents reported their child's anxiety using the Screen for Child Anxiety Related Emotional Disorders. Conditioning influenced eye gaze patterns in that children looked longer and more frequently to the eye region of the CS+ than CS- face; this effect was present only during fear acquisition, not at baseline or extinction. Furthermore, consistent with past work in adults, anxiety symptoms were associated with eye gaze avoidance. Finally, gaze duration to the eye region mediated the effect of anxious traits on self-reported fear during acquisition. Anxiety symptoms in children relate to face-viewing strategies deployed in the context of a fear learning experiment. This relationship may inform attempts to understand the relationship between pediatric anxiety symptoms and learning. © 2017 Association for Child and Adolescent Mental Health.

  11. Identification of proteins that may directly interact with human RPA.

    Science.gov (United States)

    Nakaya, Ryou; Takaya, Junichiro; Onuki, Takeshi; Moritani, Mariko; Nozaki, Naohito; Ishimi, Yukio

    2010-11-01

    RPA, which consisted of three subunits (RPA1, 2 and 3), plays essential roles in DNA transactions. At the DNA replication forks, RPA binds to single-stranded DNA region to stabilize the structure and to assemble other replication proteins. Interactions between RPA and several replication proteins have been reported but the analysis is not comprehensive. We systematically performed the qualitative analysis to identify RPA interaction partners to understand the protein-protein interaction at the replication forks. We expressed in insect cells the three subunits of human RPA, together with one replication protein, which is present at the forks under normal conditions and/or under the replication stress conditions, to examine the interaction. Among 30 proteins examined in total, it was found that at least 14 proteins interacted with RPA. RPA interacted with MCM3-7, MCM-BP and CDC45 proteins among the proteins that play roles in the initiation and the elongation of the DNA replication. RPA bound with TIPIN, CLASPIN and RAD17, which are involved in the DNA replication checkpoint functions. RPA also bound with cyclin-dependent kinases and an amino-terminal fragment of Rb protein that negatively regulates DNA replication. These results suggest that RPA interacts with the specific proteins among those that play roles in the regulation of the replication fork progression.

  12. Direct human DNA protection by Coriolus versicolor (Yunzhi) extract.

    Science.gov (United States)

    Szeto, Yim Tong; Lau, Po Chun; Kalle, Wouter; Pak, Sok Cheon

    2013-07-01

    Scientific evidence has shown Coriolus versicolor (L. ex Fr.) Quel (also known as Yunzhi) has the role of immunomodulator in therapeutic effect. The aim of this in vitro study was to investigate the antioxidative effect of Yunzhi and to explore the mechanisms behind its DNA protection. Commercial Yunzhi extract was dissolved in water and diluted in five concentrations (10(1)-10(5) μg/L) with appropriate buffers. Lymphocytes harvested from three healthy subjects were incubated with Yunzhi extract for 30 min. Cells were then subjected to 5 min oxidant challenge by 45 μM hydrogen peroxide. The standard alkaline comet (SAC) assay and lysed cell comet (LCC) assay were performed in parallel. DNA damage of each treatment was scored under a fluorescence microscope and compared with the cells without Yunzhi pretreatment. U-shaped dose-response was seen in both versions of the comet assay. Yunzhi at 10(4) μg/L demonstrated a genoprotective effect against oxidative damage in the SAC assay (25% decrease in comet score). In the LCC assay, a trend of protection in lymphocytes was observed but it did not reach statistical significance. A direct antioxidant effect of Yunzhi against oxidant challenge on the DNA of lymphocytes was evidenced. The active component in Yunzhi was likely to be membrane permeable.

  13. The Measure of Human Error: Direct and Indirect Performance Shaping Factors

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring; Candice D. Griffith; Jeffrey C. Joe

    2007-08-01

    The goal of performance shaping factors (PSFs) is to provide measures to account for human performance. PSFs fall into two categories—direct and indirect measures of human performance. While some PSFs such as “time to complete a task” are directly measurable, other PSFs, such as “fitness for duty,” can only be measured indirectly through other measures and PSFs, such as through fatigue measures. This paper explores the role of direct and indirect measures in human reliability analysis (HRA) and the implications that measurement theory has on analyses and applications using PSFs. The paper concludes with suggestions for maximizing the reliability and validity of PSFs.

  14. See You See Me: the Role of Eye Contact in Multimodal Human-Robot Interaction

    Science.gov (United States)

    XU, TIAN (LINGER); ZHANG, HUI; YU, CHEN

    2016-01-01

    We focus on a fundamental looking behavior in human-robot interactions – gazing at each other’s face. Eye contact and mutual gaze between two social partners are critical in smooth human-human interactions. Therefore, investigating at what moments and in what ways a robot should look at a human user’s face as a response to the human’s gaze behavior is an important topic. Toward this goal, we developed a gaze-contingent human-robot interaction system, which relied on momentary gaze behaviors from a human user to control an interacting robot in real time. Using this system, we conducted an experiment in which human participants interacted with the robot in a joint attention task. In the experiment, we systematically manipulated the robot’s gaze toward the human partner’s face in real time and then analyzed the human’s gaze behavior as a response to the robot’s gaze behavior. We found that more face looks from the robot led to more look-backs (to the robot’s face) from human participants and consequently created more mutual gaze and eye contact between the two. Moreover, participants demonstrated more coordinated and synchronized multimodal behaviors between speech and gaze when more eye contact was successfully established and maintained. PMID:28966875

  15. Differential diagnosis and management of human-directed aggression in cats.

    Science.gov (United States)

    Frank, Diane; Dehasse, Joel

    2003-03-01

    Human-directed aggression in cats should be evaluated as a multifactorial problem. It results from the combined actions of heredity, environment, learning, human social requirements (or needs), client interactions, lack of understanding of normal feline behavior, unrealistic client expectations, and lack of meeting the cat's basic ethologic needs. Managing human-directed aggression in cats encompasses the use of environmental modification, therapies, and, when and if needed, regulatory drugs so as to increase learning capabilities and adaptation and decrease danger to the human victims.

  16. Head movements evoked in alert rhesus monkey by vestibular prosthesis stimulation: implications for postural and gaze stabilization.

    Directory of Open Access Journals (Sweden)

    Diana E Mitchell

    Full Text Available The vestibular system detects motion of the head in space and in turn generates reflexes that are vital for our daily activities. The eye movements produced by the vestibulo-ocular reflex (VOR play an essential role in stabilizing the visual axis (gaze, while vestibulo-spinal reflexes ensure the maintenance of head and body posture. The neuronal pathways from the vestibular periphery to the cervical spinal cord potentially serve a dual role, since they function to stabilize the head relative to inertial space and could thus contribute to gaze (eye-in-head + head-in-space and posture stabilization. To date, however, the functional significance of vestibular-neck pathways in alert primates remains a matter of debate. Here we used a vestibular prosthesis to 1 quantify vestibularly-driven head movements in primates, and 2 assess whether these evoked head movements make a significant contribution to gaze as well as postural stabilization. We stimulated electrodes implanted in the horizontal semicircular canal of alert rhesus monkeys, and measured the head and eye movements evoked during a 100 ms time period for which the contribution of longer latency voluntary inputs to the neck would be minimal. Our results show that prosthetic stimulation evoked significant head movements with latencies consistent with known vestibulo-spinal pathways. Furthermore, while the evoked head movements were substantially smaller than the coincidently evoked eye movements, they made a significant contribution to gaze stabilization, complementing the VOR to ensure that the appropriate gaze response is achieved. We speculate that analogous compensatory head movements will be evoked when implanted prosthetic devices are transitioned to human patients.

  17. A comparison of facial color pattern and gazing behavior in canid species suggests gaze communication in gray wolves (Canis lupus.

    Directory of Open Access Journals (Sweden)

    Sayoko Ueda

    Full Text Available As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear, B-type (only the eye position is clear, and C-type (both the pupil and eye position are unclear. A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication.

  18. Remote gaze tracking system for 3D environments.

    Science.gov (United States)

    Congcong Liu; Herrup, Karl; Shi, Bertram E

    2017-07-01

    Eye tracking systems are typically divided into two categories: remote and mobile. Remote systems, where the eye tracker is located near the object being viewed by the subject, have the advantage of being less intrusive, but are typically used for tracking gaze points on fixed two dimensional (2D) computer screens. Mobile systems such as eye tracking glasses, where the eye tracker are attached to the subject, are more intrusive, but are better suited for cases where subjects are viewing objects in the three dimensional (3D) environment. In this paper, we describe how remote gaze tracking systems developed for 2D computer screens can be used to track gaze points in a 3D environment. The system is non-intrusive. It compensates for small head movements by the user, so that the head need not be stabilized by a chin rest or bite bar. The system maps the 3D gaze points of the user onto 2D images from a scene camera and is also located remotely from the subject. Measurement results from this system indicate that it is able to estimate gaze points in the scene camera to within one degree over a wide range of head positions.

  19. Face age modulates gaze following in young adults.

    Science.gov (United States)

    Ciardo, Francesca; Marino, Barbara F M; Actis-Grosso, Rossana; Rossetti, Angela; Ricciardelli, Paola

    2014-04-22

    Gaze-following behaviour is considered crucial for social interactions which are influenced by social similarity. We investigated whether the degree of similarity, as indicated by the perceived age of another person, can modulate gaze following. Participants of three different age-groups (18-25; 35-45; over 65) performed an eye movement (a saccade) towards an instructed target while ignoring the gaze-shift of distracters of different age-ranges (6-10; 18-25; 35-45; over 70). The results show that gaze following was modulated by the distracter face age only for young adults. Particularly, the over 70 year-old distracters exerted the least interference effect. The distracters of a similar age-range as the young adults (18-25; 35-45) had the most effect, indicating a blurred own-age bias (OAB) only for the young age group. These findings suggest that face age can modulate gaze following, but this modulation could be due to factors other than just OAB (e.g., familiarity).

  20. Comparison of dogs and humans in visual scanning of social interaction

    OpenAIRE

    Törnqvist, Heini; Somppi, Sanni; Koskela, Aija; Krause, Christina M.; Vainio, Outi; Kujala, Miiamaaria V.

    2015-01-01

    Previous studies have demonstrated similarities in gazing behaviour of dogs and humans, but comparisons under similar conditions are rare, and little is known about dogs' visual attention to social scenes. Here, we recorded the eye gaze of dogs while they viewed images containing two humans or dogs either interacting socially or facing away: the results were compared with equivalent data measured from humans. Furthermore, we compared the gazing behaviour of two dog and two human populations w...

  1. Risk factors for human-directed canine aggression in a referral level clinical population.

    Science.gov (United States)

    Lord, M; Casey, R A; Loftus, B A; Blackwell, E J

    2017-07-07

    Risk factors for human-directed aggression were investigated using retrospective analysis of data from a referral-level clinical behaviour population in the UK. A sample of 200 cases involving human-directed canine aggression and 200 control cases involving no instance of human-directed aggression were selected at random from a population of 746 cases. The final model suggested that clinical cases with human-directed aggression were significantly younger than those presenting with other undesired behaviours (P=0.008) and that male dogs were 1.4 times more likely to be aggressive towards human beings than female dogs (P=0.019). Dogs were 1.7 times more likely to be aggressive towards people if they had attended more than five puppy classes than if they had never attended puppy class (P=0.015) and that dogs were 2.8 times more likely to be aggressive towards human beings if there was another dog between 0 months and 24 months of age in the home (P=0.004). These factors only account for 7 per cent to 10 per cent of the variance between the human-directed aggression population and the control population, but factors such as attendance at puppy classes and numbers of dogs in the household suggest the need for longitudinal studies to investigate temporal relationships.

  2. COGAIN2009 - "Gaze interaction for those who want it most"

    DEFF Research Database (Denmark)

    , with substantial amounts of applications to support communication, learning and entertainment already in use. However, there are still some uncertainties about this new technology amongst communication specialists and funding institutions. The 5th COGAIN conference will focus on spreading the experiences of people...... using gaze interaction in their daily life to potential users and specialists who have yet to benefit from it. The theme of the conference is "Gaze interaction for those who want it most". We present a total of 18 papers that have been reviewed and accepted by leading researchers and communication...... specialists. Several papers address gaze-based access to computer applications and several papers focus on environmental control. Previous COGAIN conferences have been a most effective launch pad for original new research ideas. Some of them have since found their way into journals and other conferences...

  3. 77 FR 71695 - Secondary Direct Food Additives Permitted in Food for Human Consumption; Sodium...

    Science.gov (United States)

    2012-12-04

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 173 [Docket No. FDA-2011-F-0853] Secondary Direct Food Additives Permitted in Food for Human Consumption; Sodium... dodecylbenzenesulfonate (CAS No. 25155-30-0) as an antimicrobial agent for use in wash water for fruits and vegetables...

  4. Associative theories of goal-directed behaviour: a case for animal-human translational models

    NARCIS (Netherlands)

    de Wit, S.; Dickinson, A.

    2009-01-01

    Associative accounts of goal-directed action, developed in the fields of human ideomotor action and that of animal learning, can capture cognitive belief-desire psychology of human decision-making. Whereas outcome-response accounts can account for the fact that the thought of a goal can call to mind

  5. 76 FR 41687 - Food Additives Permitted for Direct Addition to Food for Human Consumption; Hydroxypropyl Cellulose

    Science.gov (United States)

    2011-07-15

    ... Organization and the World Health Organization (FAO/WHO) Expert Committee for Food Additives (JECFA) has... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 [Docket No. FDA-2010-F-0103] Food Additives Permitted for Direct Addition to Food for Human Consumption...

  6. Human projected area factors for detailed direct and diffuse solar radiation analysis

    DEFF Research Database (Denmark)

    Kubaha, K.; Fiala, D.; Toftum, Jørn

    2004-01-01

    Projected area factors for individual segments of the standing and sedentary human body were modelled for both direct and diffuse solar radiation using detailed 3D geometry and radiation models. The local projected area factors with respect to direct short-wave radiation are a function of the solar...

  7. Model-driven gaze simulation for the blind person in face-to-face communication

    NARCIS (Netherlands)

    Qiu, S.; Anas, S.A.B.; Osawa, H.; Rauterberg, G.W.M.; Hu, J.

    2016-01-01

    In face-to-face communication, eye gaze is integral to a conversation to supplement verbal language. The sighted often uses eye gaze to convey nonverbal information in social interactions, which a blind conversation partner cannot access and react to them. In this paper, we present E-Gaze glasses

  8. Look together : Using gaze for assisting co-located collaborative search

    NARCIS (Netherlands)

    Zhang, Y.; Pfeuffer, Ken; Chong, Ming Ki; Alexander, Jason; Bulling, Andreas; Gellersen, Hans

    2017-01-01

    Gaze information provides indication of users focus which complements remote collaboration tasks, as distant users can see their partner’s focus. In this paper, we apply gaze for co-located collaboration, where users’ gaze locations are presented on the same display, to help collaboration between

  9. Gaze Step Distributions Reflect Fixations and Saccades: A Comment on Stephen and Mirman (2010)

    Science.gov (United States)

    Bogartz, Richard S.; Staub, Adrian

    2012-01-01

    In three experimental tasks Stephen and Mirman (2010) measured gaze steps, the distance in pixels between gaze positions on successive samples from an eyetracker. They argued that the distribution of gaze steps is best fit by the lognormal distribution, and based on this analysis they concluded that interactive cognitive processes underlie eye…

  10. "Gaze Leading": Initiating Simulated Joint Attention Influences Eye Movements and Choice Behavior

    Science.gov (United States)

    Bayliss, Andrew P.; Murphy, Emily; Naughtin, Claire K.; Kritikos, Ada; Schilbach, Leonhard; Becker, Stefanie I.

    2013-01-01

    Recent research in adults has made great use of the gaze cuing paradigm to understand the behavior of the follower in joint attention episodes. We implemented a gaze leading task to investigate the initiator--the other person in these triadic interactions. In a series of gaze-contingent eye-tracking studies, we show that fixation dwell time upon…

  11. A comprehensive gaze stabilization controller based on cerebellar internal models

    DEFF Research Database (Denmark)

    Vannucci, Lorenzo; Falotico, Egidio; Tolu, Silvia

    2017-01-01

    . The VOR works in conjunction with the opto-kinetic reflex (OKR), which is a visual feedback mechanism that allows to move the eye at the same speed as the observed scene. Together they keep the image stationary on the retina. In this work we implement on a humanoid robot a model of gaze stabilization...... based on the coordination of VCR and VOR and OKR. The model, inspired by neuroscientific cerebellar theories, is provided with learning and adaptation capabilities based on internal models. We present the results for the gaze stabilization model on three sets of experiments conducted on the SABIAN robot...

  12. Human-directed local autonomy for motion guidance and coordination in an intelligent manufacturing system

    Science.gov (United States)

    Alford, W. A.; Kawamura, Kazuhiko; Wilkes, Don M.

    1997-12-01

    This paper discusses the problem of integrating human intelligence and skills into an intelligent manufacturing system. Our center has jointed the Holonic Manufacturing Systems (HMS) Project, an international consortium dedicated to developing holonic systems technologies. One of our contributions to this effort is in Work Package 6: flexible human integration. This paper focuses on one activity, namely, human integration into motion guidance and coordination. Much research on intelligent systems focuses on creating totally autonomous agents. At the Center for Intelligent Systems (CIS), we design robots that interact directly with a human user. We focus on using the natural intelligence of the user to simplify the design of a robotic system. The problem is finding ways for the user to interact with the robot that are efficient and comfortable for the user. Manufacturing applications impose the additional constraint that the manufacturing process should not be disturbed; that is, frequent interacting with the user could degrade real-time performance. Our research in human-robot interaction is based on a concept called human directed local autonomy (HuDL). Under this paradigm, the intelligent agent selects and executes a behavior or skill, based upon directions from a human user. The user interacts with the robot via speech, gestures, or other media. Our control software is based on the intelligent machine architecture (IMA), an object-oriented architecture which facilitates cooperation and communication among intelligent agents. In this paper we describe our research testbed, a dual-arm humanoid robot and human user, and the use of this testbed for a human directed sorting task. We also discuss some proposed experiments for evaluating the integration of the human into the robot system. At the time of this writing, the experiments have not been completed.

  13. Direct 2-D reconstructions of conductivity and permittivity from EIT data on a human chest.

    Science.gov (United States)

    Herrera, Claudia N L; Vallejo, Miguel F M; Mueller, Jennifer L; Lima, Raul G

    2015-01-01

    A novel direct D-bar reconstruction algorithm is presented for reconstructing a complex conductivity distribution from 2-D EIT data. The method is applied to simulated data and archival human chest data. Permittivity reconstructions with the aforementioned method and conductivity reconstructions with the previously existing nonlinear D-bar method for real-valued conductivities depicting ventilation and perfusion in the human chest are presented. This constitutes the first fully nonlinear D-bar reconstructions of human chest data and the first D-bar permittivity reconstructions of experimental data. The results of the human chest data reconstructions are compared on a circular domain versus a chest-shaped domain.

  14. Examining the durability of incidentally learned trust from gaze cues.

    Science.gov (United States)

    Strachan, James W A; Tipper, Steven P

    2017-10-01

    In everyday interactions we find our attention follows the eye gaze of faces around us. As this cueing is so powerful and difficult to inhibit, gaze can therefore be used to facilitate or disrupt visual processing of the environment, and when we experience this we infer information about the trustworthiness of the cueing face. However, to date no studies have investigated how long these impressions last. To explore this we used a gaze-cueing paradigm where faces consistently demonstrated either valid or invalid cueing behaviours. Previous experiments show that valid faces are subsequently rated as more trustworthy than invalid faces. We replicate this effect (Experiment 1) and then include a brief interference task in Experiment 2 between gaze cueing and trustworthiness rating, which weakens but does not completely eliminate the effect. In Experiment 3, we explore whether greater familiarity with the faces improves the durability of trust learning and find that the effect is more resilient with familiar faces. Finally, in Experiment 4, we push this further and show that evidence of trust learning can be seen up to an hour after cueing has ended. Taken together, our results suggest that incidentally learned trust can be durable, especially for faces that deceive.

  15. Attention, Exposure Duration, and Gaze Shifting in Naming Performance

    Science.gov (United States)

    Roelofs, Ardi

    2011-01-01

    Two experiments are reported in which the role of attribute exposure duration in naming performance was examined by tracking eye movements. Participants were presented with color-word Stroop stimuli and left- or right-pointing arrows on different sides of a computer screen. They named the color attribute and shifted their gaze to the arrow to…

  16. Gaze-based hints during child-robot gameplay

    NARCIS (Netherlands)

    Mwangi, E.; Barakova, Emilia I.; Diaz, M.L.Z.; Mallofre, A.C.; Rauterberg, G.W.M.; Kheddar, A.; Yoshida, E.; Sam Ge, S.; Suzuki, K.; Cabibihan, J.J.; Eyssel, F.; He, H.

    2017-01-01

    This paper presents a study that examines whether gaze hints provided by a robot tutor influences the behavior of children in a card matching game. In this regard, we conducted a within-subjects experiment, in which children played a card game “Memory” in the presence of a robot tutor in two

  17. Self-Monitoring of Gaze in High Functioning Autism

    Science.gov (United States)

    Grynszpan, Ouriel; Nadel, Jacqueline; Martin, Jean-Claude; Simonin, Jerome; Bailleul, Pauline; Wang, Yun; Gepner, Daniel; Le Barillier, Florence; Constant, Jacques

    2012-01-01

    Atypical visual behaviour has been recently proposed to account for much of social misunderstanding in autism. Using an eye-tracking system and a gaze-contingent lens display, the present study explores self-monitoring of eye motion in two conditions: free visual exploration and guided exploration via blurring the visual field except for the focal…

  18. Maori in the Kingdom of the Gaze: Subjects or Critics?

    Science.gov (United States)

    Mika, Carl; Stewart, Georgina

    2016-01-01

    For Maori, a real opportunity exists to flesh out some terms and concepts that Western thinkers have adopted and that precede disciplines but necessarily inform them. In this article, we are intent on describing one of these precursory phenomena--Foucault's Gaze--within a framework that accords with a Maori philosophical framework. Our discussion…

  19. Strange-face illusions during inter-subjective gazing.

    Science.gov (United States)

    Caputo, Giovanni B

    2013-03-01

    In normal observers, gazing at one's own face in the mirror for a few minutes, at a low illumination level, triggers the perception of strange faces, a new visual illusion that has been named 'strange-face in the mirror'. Individuals see huge distortions of their own faces, but they often see monstrous beings, archetypal faces, faces of relatives and deceased, and animals. In the experiment described here, strange-face illusions were perceived when two individuals, in a dimly lit room, gazed at each other in the face. Inter-subjective gazing compared to mirror-gazing produced a higher number of different strange-faces. Inter-subjective strange-face illusions were always dissociative of the subject's self and supported moderate feeling of their reality, indicating a temporary lost of self-agency. Unconscious synchronization of event-related responses to illusions was found between members in some pairs. Synchrony of illusions may indicate that unconscious response-coordination is caused by the illusion-conjunction of crossed dissociative strange-faces, which are perceived as projections into each other's visual face of reciprocal embodied representations within the pair. Inter-subjective strange-face illusions may be explained by the subject's embodied representations (somaesthetic, kinaesthetic and motor facial pattern) and the other's visual face binding. Unconscious facial mimicry may promote inter-subjective illusion-conjunction, then unconscious joint-action and response-coordination. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Depth Compensation Model for Gaze Estimation in Sport Analysis

    DEFF Research Database (Denmark)

    Batista Narcizo, Fabricio; Hansen, Dan Witzner

    2015-01-01

    is tested in a totally controlled environment with aim to check the influences of eye tracker parameters and ocular biometric parameters on its behavior. We also present a gaze estimation method based on epipolar geometry for binocular eye tracking setups. The depth compensation model has shown very...

  1. Children's Bricolage under the Gaze of Teachers in Sociodramatic Play

    Science.gov (United States)

    Tam, Po Chi

    2013-01-01

    Drawing on the theory of dialogism and the literature on children's culture and cultural resistance, this article investigates the contextual and textual features of the cultural making of a group of children in sociodramatic play in a Hong Kong kindergarten. Different from other, similar studies, this study reports that under the gaze of the…

  2. Quality control of geological voxel models using experts' gaze

    NARCIS (Netherlands)

    Maanen, P.P. van; Busschers, F.S.; Brouwer, A.M.; Meulen, M.J. van der; Erp, J.B.F. van

    2015-01-01

    Due to an expected increase in geological voxel model data-flow and user demands, the development of improved quality control for such models is crucial. This study explores the potential of a new type of quality control that improves the detection of errors by just using gaze behavior of 12

  3. Quality Control of Geological Voxel Models using Experts' Gaze

    NARCIS (Netherlands)

    van Maanen, Peter-Paul; Busschers, Freek S.; Brouwer, Anne-Marie; van der Meulendijk, Michiel J.; van Erp, Johannes Bernardus Fransiscus

    Due to an expected increase in geological voxel model data-flow and user demands, the development of improved quality control for such models is crucial. This study explores the potential of a new type of quality control that improves the detection of errors by just using gaze behavior of 12

  4. Learning to interact with a computer by gaze

    DEFF Research Database (Denmark)

    Aoki, Hirotaka; Hansen, John Paulin; Itoh, Kenji

    2008-01-01

    that inefficient eye movements was dramatically reduced after only 15 to 25 sentences of typing, equal to approximately 3-4 hours of practice. The performance data fits a general learning model based on the power law of practice. The learning model can be used to estimate further improvements in gaze typing...

  5. Direction of movement is encoded in the human primary motor cortex.

    Directory of Open Access Journals (Sweden)

    Carolien M Toxopeus

    Full Text Available The present study investigated how direction of hand movement, which is a well-described parameter in cerebral organization of motor control, is incorporated in the somatotopic representation of the manual effector system in the human primary motor cortex (M1. Using functional magnetic resonance imaging (fMRI and a manual step-tracking task we found that activation patterns related to movement in different directions were spatially disjoint within the representation area of the hand on M1. Foci of activation related to specific movement directions were segregated within the M1 hand area; activation related to direction 0° (right was located most laterally/superficially, whereas directions 180° (left and 270° (down elicited activation more medially within the hand area. Activation related to direction 90° was located between the other directions. Moreover, by investigating differences between activations related to movement along the horizontal (0°+180° and vertical (90°+270° axis, we found that activation related to the horizontal axis was located more anterolaterally/dorsally in M1 than for the vertical axis, supporting that activations related to individual movement directions are direction- and not muscle related. Our results of spatially segregated direction-related activations in M1 are in accordance with findings of recent fMRI studies on neural encoding of direction in human M1. Our results thus provide further evidence for a direct link between direction as an organizational principle in sensorimotor transformation and movement execution coded by effector representations in M1.

  6. Flexible coordination of stationary and mobile conversations with gaze: Resource allocation among multiple joint activities

    Directory of Open Access Journals (Sweden)

    Eric Mayor

    2016-10-01

    Full Text Available Gaze is instrumental in coordinating face-to-face social interactions. But little is known about gaze use when social interactions co-occur with other joint activities. We investigated the case of walking while talking. We assessed how gaze gets allocated among various targets in mobile conversations, whether allocation of gaze to other targets affects conversational coordination, and whether reduced availability of gaze for conversational coordination affects conversational performance and content. In an experimental study, pairs were videotaped in four conditions of mobility (standing still, talking while walking along a straight-line itinerary, talking while walking along a complex itinerary, or walking along a complex itinerary with no conversational task. Gaze to partners was substantially reduced in mobile conversations, but gaze was still used to coordinate conversation via displays of mutual orientation, and conversational performance and content was not different between stationary and mobile conditions. Results expand the phenomena of multitasking to joint activities.

  7. Gaze Duration Biases for Colours in Combination with Dissonant and Consonant Sounds: A Comparative Eye-Tracking Study with Orangutans.

    Science.gov (United States)

    Mühlenbeck, Cordelia; Liebal, Katja; Pritsch, Carla; Jacobsen, Thomas

    2015-01-01

    Research on colour preferences in humans and non-human primates suggests similar patterns of biases for and avoidance of specific colours, indicating that these colours are connected to a psychological reaction. Similarly, in the acoustic domain, approach reactions to consonant sounds (considered as positive) and avoidance reactions to dissonant sounds (considered as negative) have been found in human adults and children, and it has been demonstrated that non-human primates are able to discriminate between consonant and dissonant sounds. Yet it remains unclear whether the visual and acoustic approach-avoidance patterns remain consistent when both types of stimuli are combined, how they relate to and influence each other, and whether these are similar for humans and other primates. Therefore, to investigate whether gaze duration biases for colours are similar across primates and whether reactions to consonant and dissonant sounds cumulate with reactions to specific colours, we conducted an eye-tracking study in which we compared humans with one species of great apes, the orangutans. We presented four different colours either in isolation or in combination with consonant and dissonant sounds. We hypothesised that the viewing time for specific colours should be influenced by dissonant sounds and that previously existing avoidance behaviours with regard to colours should be intensified, reflecting their association with negative acoustic information. The results showed that the humans had constant gaze durations which were independent of the auditory stimulus, with a clear avoidance of yellow. In contrast, the orangutans did not show any clear gaze duration bias or avoidance of colours, and they were also not influenced by the auditory stimuli. In conclusion, our findings only partially support the previously identified pattern of biases for and avoidance of specific colours in humans and do not confirm such a pattern for orangutans.

  8. Gaze-Stabilizing Central Vestibular Neurons Project Asymmetrically to Extraocular Motoneuron Pools.

    Science.gov (United States)

    Schoppik, David; Bianco, Isaac H; Prober, David A; Douglass, Adam D; Robson, Drew N; Li, Jennifer M B; Greenwood, Joel S F; Soucy, Edward; Engert, Florian; Schier, Alexander F

    2017-11-22

    Within reflex circuits, specific anatomical projections allow central neurons to relay sensations to effectors that generate movements. A major challenge is to relate anatomical features of central neural populations, such as asymmetric connectivity, to the computations the populations perform. To address this problem, we mapped the anatomy, modeled the function, and discovered a new behavioral role for a genetically defined population of central vestibular neurons in rhombomeres 5-7 of larval zebrafish. First, we found that neurons within this central population project preferentially to motoneurons that move the eyes downward. Concordantly, when the entire population of asymmetrically projecting neurons was stimulated collectively, only downward eye rotations were observed, demonstrating a functional correlate of the anatomical bias. When these neurons are ablated, fish failed to rotate their eyes following either nose-up or nose-down body tilts. This asymmetrically projecting central population thus participates in both upward and downward gaze stabilization. In addition to projecting to motoneurons, central vestibular neurons also receive direct sensory input from peripheral afferents. To infer whether asymmetric projections can facilitate sensory encoding or motor output, we modeled differentially projecting sets of central vestibular neurons. Whereas motor command strength was independent of projection allocation, asymmetric projections enabled more accurate representation of nose-up stimuli. The model shows how asymmetric connectivity could enhance the representation of imbalance during nose-up postures while preserving gaze stabilization performance. Finally, we found that central vestibular neurons were necessary for a vital behavior requiring maintenance of a nose-up posture: swim bladder inflation. These observations suggest that asymmetric connectivity in the vestibular system facilitates representation of ethologically relevant stimuli without

  9. Direct Lineage Reprogramming Reveals Disease-Specific Phenotypes of Motor Neurons from Human ALS Patients

    Directory of Open Access Journals (Sweden)

    Meng-Lu Liu

    2016-01-01

    Full Text Available Subtype-specific neurons obtained from adult humans will be critical to modeling neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS. Here, we show that adult human skin fibroblasts can be directly and efficiently converted into highly pure motor neurons without passing through an induced pluripotent stem cell stage. These adult human induced motor neurons (hiMNs exhibit the cytological and electrophysiological features of spinal motor neurons and form functional neuromuscular junctions (NMJs with skeletal muscles. Importantly, hiMNs converted from ALS patient fibroblasts show disease-specific degeneration manifested through poor survival, soma shrinkage, hypoactivity, and an inability to form NMJs. A chemical screen revealed that the degenerative features of ALS hiMNs can be remarkably rescued by the small molecule kenpaullone. Taken together, our results define a direct and efficient strategy to obtain disease-relevant neuronal subtypes from adult human patients and reveal their promising value in disease modeling and drug identification.

  10. Driving and driven architectures of directed small-world human brain functional networks.

    Directory of Open Access Journals (Sweden)

    Chaogan Yan

    Full Text Available Recently, increasing attention has been focused on the investigation of the human brain connectome that describes the patterns of structural and functional connectivity networks of the human brain. Many studies of the human connectome have demonstrated that the brain network follows a small-world topology with an intrinsically cohesive modular structure and includes several network hubs in the medial parietal regions. However, most of these studies have only focused on undirected connections between regions in which the directions of information flow are not taken into account. How the brain regions causally influence each other and how the directed network of human brain is topologically organized remain largely unknown. Here, we applied linear multivariate Granger causality analysis (GCA and graph theoretical approaches to a resting-state functional MRI dataset with a large cohort of young healthy participants (n = 86 to explore connectivity patterns of the population-based whole-brain functional directed network. This directed brain network exhibited prominent small-world properties, which obviously improved previous results of functional MRI studies showing weak small-world properties in the directed brain networks in terms of a kernel-based GCA and individual analysis. This brain network also showed significant modular structures associated with 5 well known subsystems: fronto-parietal, visual, paralimbic/limbic, subcortical and primary systems. Importantly, we identified several driving hubs predominantly located in the components of the attentional network (e.g., the inferior frontal gyrus, supplementary motor area, insula and fusiform gyrus and several driven hubs predominantly located in the components of the default mode network (e.g., the precuneus, posterior cingulate gyrus, medial prefrontal cortex and inferior parietal lobule. Further split-half analyses indicated that our results were highly reproducible between two

  11. Advancing Direct Corporate Accountability in International Human Rights Law: The Role of State-Owned Enterprises

    OpenAIRE

    Ma, Xili

    2017-01-01

    Resorting to the immensely State-centric international legal system to regulate corporate human rights abuses is often viewed as inadequate. Among many proposals aiming at filling the international regulatory gaps, imposing international human rights obligations directly on corporations is a bold one, which, due to profound doctrinal and practical challenges, has yet to be agreed upon or established. However, State-Owned Enterprises (SOEs), given its prima facie “State-Business nexus” that bl...

  12. Humans tend to walk in circles as directed by memorized visual locations at large distances

    OpenAIRE

    Consolo, Patricia; Holanda, Humberto C.; Fukusima, Sérgio S.

    2014-01-01

    Human veering while walking blindfolded or walking straight without any visual cues has been widely studied over the last 100 years, but the results are still controversial. The present study attempted to describe and understand the human ability to maintain the direction of a trajectory while walking without visual or audio cues with reference to a proposed mathematical model and using data collected by a global positioning system (GPS). Fifteen right-handed people of both genders, aged 18-3...

  13. The effect of oxytocin on human-directed social behaviour in dogs (Canis familiaris).

    Science.gov (United States)

    Kis, Anna; Ciobica, Alin; Topál, József

    2017-08-01

    The oxytocin system has recently received increasing attention due to its effect on complex human behaviours. In parallel to this, over the past couple of decades, the human-analogue social behaviour of dogs has been intensively studied. Combining these two lines of research (e.g. studying the relationship between dog social behaviour and the oxytocin system) is a promising new research area. The present paper reviews the existing literature on how oxytocin is related to different aspects of human-directed social behaviour in dogs. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Directional dominance on stature and cognition in diverse human populations

    DEFF Research Database (Denmark)

    Joshi, Peter K; Esko, Tonu; Mattsson, Hannele

    2015-01-01

    is predicted for traits under directional evolutionary selection, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been....... confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance...

  15. The Metamorphosis of Polyphemus's Gaze in Marij Pregelj's Painting (1913-1967

    Directory of Open Access Journals (Sweden)

    Jure Mikuž

    2015-04-01

    Full Text Available In 1949-1951 Marij Pregelj, one of the most interesting Slovenian modernist painters, illustrated his version of Homer's Iliad and Odsssey. His illustrations were presented in the time of socialist realist aesthetics announce a reintegration of Slovenian art into the global (Western context. Among the illustrations is the figure of Cyclops devouring Odysseus' comrades. The image of the one-eyed giant Polyphemus is one which concerned Pregelj all his life: the painter, whose vocation is most dependent on the gaze, can show one eye in profile. And the profiles of others' faces and of his own face interested Pregelj his whole life through. Not only people but also objects were one-eyed: the rosette of a cathedral, which changes into a human figure, a washing machine door, a meat grinder's orifice, a blind “windeye” or window, and so on. The themes of his final two paintings, which he, already more than a year before his boding senseless death at the age of 54, executed but did not complete, are Polyphemus and the Portrait of His Son Vasko. In the first, blood flows from the pricked-out eye towards a stylized camera, in the second, the gaze of the son, an enthusiastic filmmaker, extends to the camera that will displace the father's brush.

  16. A gaze-contingent display to study contrast sensitivity under natural viewing conditions

    Science.gov (United States)

    Dorr, Michael; Bex, Peter J.

    2011-03-01

    Contrast sensitivity has been extensively studied over the last decades and there are well-established models of early vision that were derived by presenting the visual system with synthetic stimuli such as sine-wave gratings near threshold contrasts. Natural scenes, however, contain a much wider distribution of orientations, spatial frequencies, and both luminance and contrast values. Furthermore, humans typically move their eyes two to three times per second under natural viewing conditions, but most laboratory experiments require subjects to maintain central fixation. We here describe a gaze-contingent display capable of performing real-time contrast modulations of video in retinal coordinates, thus allowing us to study contrast sensitivity when dynamically viewing dynamic scenes. Our system is based on a Laplacian pyramid for each frame that efficiently represents individual frequency bands. Each output pixel is then computed as a locally weighted sum of pyramid levels to introduce local contrast changes as a function of gaze. Our GPU implementation achieves real-time performance with more than 100 fps on high-resolution video (1920 by 1080 pixels) and a synthesis latency of only 1.5ms. Psychophysical data show that contrast sensitivity is greatly decreased in natural videos and under dynamic viewing conditions. Synthetic stimuli therefore only poorly characterize natural vision.

  17. Eye-Gaze Analysis of Facial Emotion Recognition and Expression in Adolescents with ASD.

    Science.gov (United States)

    Wieckowski, Andrea Trubanova; White, Susan W

    2017-01-01

    Impaired emotion recognition and expression in individuals with autism spectrum disorder (ASD) may contribute to observed social impairment. The aim of this study was to examine the role of visual attention directed toward nonsocial aspects of a scene as a possible mechanism underlying recognition and expressive ability deficiency in ASD. One recognition and two expression tasks were administered. Recognition was assessed in force-choice paradigm, and expression was assessed during scripted and free-choice response (in response to emotional stimuli) tasks in youth with ASD (n = 20) and an age-matched sample of typically developing youth (n = 20). During stimulus presentation prior to response in each task, participants' eye gaze was tracked. Youth with ASD were less accurate at identifying disgust and sadness in the recognition task. They fixated less to the eye region of stimuli showing surprise. A group difference was found during the free-choice response task, such that those with ASD expressed emotion less clearly but not during the scripted task. Results suggest altered eye gaze to the mouth region but not the eye region as a candidate mechanism for decreased ability to recognize or express emotion. Findings inform our understanding of the association between social attention and emotion recognition and expression deficits.

  18. Estimating the probability that the Taser directly causes human ventricular fibrillation.

    Science.gov (United States)

    Sun, H; Haemmerich, D; Rahko, P S; Webster, J G

    2010-04-01

    This paper describes the first methodology and results for estimating the order of probability for Tasers directly causing human ventricular fibrillation (VF). The probability of an X26 Taser causing human VF was estimated using: (1) current density near the human heart estimated by using 3D finite-element (FE) models; (2) prior data of the maximum dart-to-heart distances that caused VF in pigs; (3) minimum skin-to-heart distances measured in erect humans by echocardiography; and (4) dart landing distribution estimated from police reports. The estimated mean probability of human VF was 0.001 for data from a pig having a chest wall resected to the ribs and 0.000006 for data from a pig with no resection when inserting a blunt probe. The VF probability for a given dart location decreased with the dart-to-heart horizontal distance (radius) on the skin surface.

  19. The oldest anatomically modern humans from far southeast Europe: direct dating, culture and behavior.

    Directory of Open Access Journals (Sweden)

    Sandrine Prat

    Full Text Available BACKGROUND: Anatomically Modern Humans (AMHs are known to have spread across Europe during the period coinciding with the Middle to Upper Paleolithic transition. Whereas their dispersal into Western Europe is relatively well established, evidence of an early settlement of Eastern Europe by modern humans are comparatively scarce. METHODOLOGY/PRINCIPAL FINDING: Based on a multidisciplinary approach for the study of human and faunal remains, we describe here the oldest AMH remains from the extreme southeast Europe, in conjunction with their associated cultural and paleoecological background. We applied taxonomy, paleoecology, and taphonomy combined with geomorphology, stratigraphy, archeology and radiocarbon dating. More than 160 human bone remains have been discovered. They originate from a well documented Upper Paleolithic archeological layer (Gravettian cultural tradition from the site of Buran-Kaya III located in Crimea (Ukraine. The combination of non-metric dental traits and the morphology of the occipital bones allow us to attribute the human remains to Anatomically Modern Humans. A set of human and faunal remains from this layer has been radiocarbon dated by Accelerator Mass Spectrometry. The direct-dating results of human bone establish a secure presence of AMHs at 31,900+240/-220 BP in this region. They are the oldest direct evidence of the presence of AMHs in a well documented archeological context. Based on taphonomical observations (cut marks and distribution of skeletal elements, they represent the oldest Upper Paleolithic modern humans from Eastern Europe, showing post-mortem treatment of the dead as well. CONCLUSION/SIGNIFICANCE: These findings are essential for the debate on the spread of modern humans in Europe during the Upper Paleolithic, as well as their cultural behaviors.

  20. The oldest anatomically modern humans from far southeast Europe: direct dating, culture and behavior.

    Science.gov (United States)

    Prat, Sandrine; Péan, Stéphane C; Crépin, Laurent; Drucker, Dorothée G; Puaud, Simon J; Valladas, Hélène; Lázničková-Galetová, Martina; van der Plicht, Johannes; Yanevich, Alexander

    2011-01-01

    Anatomically Modern Humans (AMHs) are known to have spread across Europe during the period coinciding with the Middle to Upper Paleolithic transition. Whereas their dispersal into Western Europe is relatively well established, evidence of an early settlement of Eastern Europe by modern humans are comparatively scarce. Based on a multidisciplinary approach for the study of human and faunal remains, we describe here the oldest AMH remains from the extreme southeast Europe, in conjunction with their associated cultural and paleoecological background. We applied taxonomy, paleoecology, and taphonomy combined with geomorphology, stratigraphy, archeology and radiocarbon dating. More than 160 human bone remains have been discovered. They originate from a well documented Upper Paleolithic archeological layer (Gravettian cultural tradition) from the site of Buran-Kaya III located in Crimea (Ukraine). The combination of non-metric dental traits and the morphology of the occipital bones allow us to attribute the human remains to Anatomically Modern Humans. A set of human and faunal remains from this layer has been radiocarbon dated by Accelerator Mass Spectrometry. The direct-dating results of human bone establish a secure presence of AMHs at 31,900+240/-220 BP in this region. They are the oldest direct evidence of the presence of AMHs in a well documented archeological context. Based on taphonomical observations (cut marks and distribution of skeletal elements), they represent the oldest Upper Paleolithic modern humans from Eastern Europe, showing post-mortem treatment of the dead as well. These findings are essential for the debate on the spread of modern humans in Europe during the Upper Paleolithic, as well as their cultural behaviors.

  1. Outward Foreign Direct Investment and Human Capital Development: A Small Country Perspective

    Science.gov (United States)

    McDonnell, Anthony

    2008-01-01

    Purpose: The purpose of this paper is to examine the pattern of outward foreign direct investment (FDI) by Irish MNCs, and more specifically, to investigate their approach to human capital development and how these correspond to foreign MNCs in Ireland. In particular, it seeks to investigate training and development expenditure, adoption of…

  2. Adaptive eye-gaze tracking using neural-network-based user profiles to assist people with motor disability.

    Science.gov (United States)

    Sesin, Anaelis; Adjouadi, Malek; Cabrerizo, Mercedes; Ayala, Melvin; Barreto, Armando

    2008-01-01

    This study developed an adaptive real-time human-computer interface (HCI) that serves as an assistive technology tool for people with severe motor disability. The proposed HCI design uses eye gaze as the primary computer input device. Controlling the mouse cursor with raw eye coordinates results in sporadic motion of the pointer because of the saccadic nature of the eye. Even though eye movements are subtle and completely imperceptible under normal circumstances, they considerably affect the accuracy of an eye-gaze-based HCI. The proposed HCI system is novel because it adapts to each specific user's different and potentially changing jitter characteristics through the configuration and training of an artificial neural network (ANN) that is structured to minimize the mouse jitter. This task is based on feeding the ANN a user's initially recorded eye-gaze behavior through a short training session. The ANN finds the relationship between the gaze coordinates and the mouse cursor position based on the multilayer perceptron model. An embedded graphical interface is used during the training session to generate user profiles that make up these unique ANN configurations. The results with 12 subjects in test 1, which involved following a moving target, showed an average jitter reduction of 35%; the results with 9 subjects in test 2, which involved following the contour of a square object, showed an average jitter reduction of 53%. For both results, the outcomes led to trajectories that were significantly smoother and apt at reaching fixed or moving targets with relative ease and within a 5% error margin or deviation from desired trajectories. The positive effects of such jitter reduction are presented graphically for visual appreciation.

  3. An online brain-machine interface using decoding of movement direction from the human electrocorticogram

    Science.gov (United States)

    Milekovic, Tomislav; Fischer, Jörg; Pistohl, Tobias; Ruescher, Johanna; Schulze-Bonhage, Andreas; Aertsen, Ad; Rickert, Jörn; Ball, Tonio; Mehring, Carsten

    2012-08-01

    A brain-machine interface (BMI) can be used to control movements of an artificial effector, e.g. movements of an arm prosthesis, by motor cortical signals that control the equivalent movements of the corresponding body part, e.g. arm movements. This approach has been successfully applied in monkeys and humans by accurately extracting parameters of movements from the spiking activity of multiple single neurons. We show that the same approach can be realized using brain activity measured directly from the surface of the human cortex using electrocorticography (ECoG). Five subjects, implanted with ECoG implants for the purpose of epilepsy assessment, took part in our study. Subjects used directionally dependent ECoG signals, recorded during active movements of a single arm, to control a computer cursor in one out of two directions. Significant BMI control was achieved in four out of five subjects with correct directional decoding in 69%-86% of the trials (75% on average). Our results demonstrate the feasibility of an online BMI using decoding of movement direction from human ECoG signals. Thus, to achieve such BMIs, ECoG signals might be used in conjunction with or as an alternative to intracortical neural signals.

  4. Flexible and multi-directional piezoelectric energy harvester for self-powered human motion sensor

    Science.gov (United States)

    Kim, Min-Ook; Pyo, Soonjae; Oh, Yongkeun; Kang, Yunsung; Cho, Kyung-Ho; Choi, Jungwook; Kim, Jongbaeg

    2018-03-01

    A flexible piezoelectric strain energy harvester that is responsive to multi-directional input forces produced by various human motions is proposed. The structure of the harvester, which includes a polydimethylsiloxane (PDMS) bump, facilitates the effective conversion of strain energy, produced by input forces applied in random directions, into electrical energy. The structural design of the PDMS bump and frame as well as the slits in the piezoelectric polyvinylidene fluoride (PVDF) film provide mechanical flexibility and enhance the strain induced in the PVDF film under input forces applied at various angles. The amount and direction of the strain induced in PVDF can be changed by the direction of the applied force; thus, the generated output power can be varied. The measured maximum output peak voltage is 1.75, 1.29, and 0.98 V when an input force of 4 N (2 Hz) is applied at angles of 0°, 45°, and 90°, and the corresponding maximum output power is 0.064, 0.026, and 0.02 μW, respectively. Moreover, the harvester stably generates output voltage over 1.4 × 104 cycles. Thus, the proposed harvester successfully identifies and converts strain energy produced by multi-directional input forces by various human motions into electrical energy. We demonstrate the potential utility of the proposed flexible energy harvester as a self-powered human motion sensor for wireless healthcare systems.

  5. Oxytocin receptor gene polymorphisms are associated with human directed social behavior in dogs (Canis familiaris).

    Science.gov (United States)

    Kis, Anna; Bence, Melinda; Lakatos, Gabriella; Pergel, Enikő; Turcsán, Borbála; Pluijmakers, Jolanda; Vas, Judit; Elek, Zsuzsanna; Brúder, Ildikó; Földi, Levente; Sasvári-Székely, Mária; Miklósi, Adám; Rónai, Zsolt; Kubinyi, Enikő

    2014-01-01

    The oxytocin system has a crucial role in human sociality; several results prove that polymorphisms of the oxytocin receptor gene are related to complex social behaviors in humans. Dogs' parallel evolution with humans and their adaptation to the human environment has made them a useful species to model human social interactions. Previous research indicates that dogs are eligible models for behavioral genetic research, as well. Based on these previous findings, our research investigated associations between human directed social behaviors and two newly described (-212AG, 19131AG) and one known (rs8679684) single nucleotide polymorphisms (SNPs) in the regulatory regions (5' and 3' UTR) of the oxytocin receptor gene in German Shepherd (N = 104) and Border Collie (N = 103) dogs. Dogs' behavior traits have been estimated in a newly developed test series consisting of five episodes: Greeting by a stranger, Separation from the owner, Problem solving, Threatening approach, Hiding of the owner. Buccal samples were collected and DNA was isolated using standard protocols. SNPs in the 3' and 5' UTR regions were analyzed by polymerase chain reaction based techniques followed by subsequent electrophoresis analysis. The gene-behavior association analysis suggests that oxytocin receptor gene polymorphisms have an impact in both breeds on (i) proximity seeking towards an unfamiliar person, as well as their owner, and on (ii) how friendly dogs behave towards strangers, although the mediating molecular regulatory mechanisms are yet unknown. Based on these results, we conclude that similarly to humans, the social behavior of dogs towards humans is influenced by the oxytocin system.

  6. Direct evidence for human reliance on rainforest resources in late Pleistocene Sri Lanka.

    Science.gov (United States)

    Roberts, Patrick; Perera, Nimal; Wedage, Oshan; Deraniyagala, Siran; Perera, Jude; Eregama, Saman; Gledhill, Andrew; Petraglia, Michael D; Lee-Thorp, Julia A

    2015-03-13

    Human occupation of tropical rainforest habitats is thought to be a mainly Holocene phenomenon. Although archaeological and paleoenvironmental data have hinted at pre-Holocene rainforest foraging, earlier human reliance on rainforest resources has not been shown directly. We applied stable carbon and oxygen isotope analysis to human and faunal tooth enamel from four late Pleistocene-to-Holocene archaeological sites in Sri Lanka. The results show that human foragers relied primarily on rainforest resources from at least ~20,000 years ago, with a distinct preference for semi-open rainforest and rain forest edges. Homo sapiens' relationship with the tropical rainforests of South Asia is therefore long-standing, a conclusion that indicates the time-depth of anthropogenic reliance and influence on these habitats. Copyright © 2015, American Association for the Advancement of Science.

  7. Direct induction of chondrogenic cells from human dermal fibroblast culture by defined factors.

    Directory of Open Access Journals (Sweden)

    Hidetatsu Outani

    Full Text Available The repair of large cartilage defects with hyaline cartilage continues to be a challenging clinical issue. We recently reported that the forced expression of two reprogramming factors (c-Myc and Klf4 and one chondrogenic factor (SOX9 can induce chondrogenic cells from mouse dermal fibroblast culture without going through a pluripotent state. We here generated induced chondrogenic (iChon cells from human dermal fibroblast (HDF culture with the same factors. We developed a chondrocyte-specific COL11A2 promoter/enhancer lentiviral reporter vector to select iChon cells. The human iChon cells expressed marker genes for chondrocytes but not fibroblasts, and were derived from non-chondrogenic COL11A2-negative cells. The human iChon cells formed cartilage but not tumors in nude mice. This approach could lead to the preparation of cartilage directly from skin in human, without going through pluripotent stem cells.

  8. Gaze anchoring guides real but not pantomime reach-to-grasp: support for the action-perception theory.

    Science.gov (United States)

    Kuntz, Jessica R; Karl, Jenni M; Doan, Jon B; Whishaw, Ian Q

    2018-04-01

    Reach-to-grasp movements feature the integration of a reach directed by the extrinsic (location) features of a target and a grasp directed by the intrinsic (size, shape) features of a target. The action-perception theory suggests that integration and scaling of a reach-to-grasp movement, including its trajectory and the concurrent digit shaping, are features that depend upon online action pathways of the dorsal visuomotor stream. Scaling is much less accurate for a pantomime reach-to-grasp movement, a pretend reach with the target object absent. Thus, the action-perception theory proposes that pantomime movement is mediated by perceptual pathways of the ventral visuomotor stream. A distinguishing visual feature of a real reach-to-grasp movement is gaze anchoring, in which a participant visually fixates the target throughout the reach and disengages, often by blinking or looking away/averting the head, at about the time that the target is grasped. The present study examined whether gaze anchoring is associated with pantomime reaching. The eye and hand movements of participants were recorded as they reached for a ball of one of three sizes, located on a pedestal at arms' length, or pantomimed the same reach with the ball and pedestal absent. The kinematic measures for real reach-to-grasp movements were coupled to the location and size of the target, whereas the kinematic measures for pantomime reach-to-grasp, although grossly reflecting target features, were significantly altered. Gaze anchoring was also tightly coupled to the target for real reach-to-grasp movements, but there was no systematic focus for gaze, either in relation with the virtual target, the previous location of the target, or the participant's reaching hand, for pantomime reach-to-grasp. The presence of gaze anchoring during real vs. its absence in pantomime reach-to-grasp supports the action-perception theory that real, but not pantomime, reaches are online visuomotor actions and is discussed in

  9. Investigation of the direct effects of salmon calcitonin on human osteoarthritic chondrocytes

    Directory of Open Access Journals (Sweden)

    Pedersen Christian

    2010-04-01

    Full Text Available Abstract Background Calcitonin has been demonstrated to have chondroprotective effects under pre-clinical settings. It is debated whether this effect is mediated through subchondral-bone, directly on cartilage or both in combination. We investigated possible direct effects of salmon calcitonin on proteoglycans and collagen-type-II synthesis in osteoarthritic (OA cartilage. Methods Human OA cartilage explants were cultured with salmon calcitonin [100 pM-100 nM]. Direct effects of calcitonin on articular cartilage were evaluated by 1 measurement of proteoglycan synthesis by incorporation of radioactive labeled 35SO4 [5 μCi] 2 quantification of collagen-type-II formation by pro-peptides of collagen type II (PIINP ELISA, 3 QPCR expression of the calcitonin receptor in OA chondrocytes using four individual primer pairs, 4 activation of the cAMP signaling pathway by EIA and, 5 investigations of metabolic activity by AlamarBlue. Results QPCR analysis and subsequent sequencing confirmed expression of the calcitonin receptor in human chondrocytes. All doses of salmon calcitonin significantly elevated cAMP levels (P 35SO4 incorporation, with a 96% maximal induction at 10 nM (P Conclusion Calcitonin treatment increased proteoglycan and collagen synthesis in human OA cartilage. In addition to its well-established effect on subchondral bone, calcitonin may prove beneficial to the management of joint diseases through direct effects on chondrocytes.

  10. Horizontal gaze palsy with progressive scoliosis: CT and MR findings

    Energy Technology Data Exchange (ETDEWEB)

    Bomfim, Rodrigo C.; Tavora, Daniel G.F.; Nakayama, Mauro; Gama, Romulo L. [Sarah Network of Rehabilitation Hospitals, Department of Radiology, Ceara (Brazil)

    2009-02-15

    Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare congenital disorder characterized by absence of conjugate horizontal eye movements and progressive scoliosis developing in childhood and adolescence. We present a child with clinical and neuroimaging findings typical of HGPPS. CT and MRI of the brain demonstrated pons hypoplasia, absence of the facial colliculi, butterfly configuration of the medulla and a deep midline pontine cleft. We briefly discuss the imaging aspects of this rare entity in light of the current literature. (orig.)

  11. Movement-related theta rhythm in humans: coordinating self-directed hippocampal learning.

    Directory of Open Access Journals (Sweden)

    Raphael Kaplan

    Full Text Available The hippocampus is crucial for episodic or declarative memory and the theta rhythm has been implicated in mnemonic processing, but the functional contribution of theta to memory remains the subject of intense speculation. Recent evidence suggests that the hippocampus might function as a network hub for volitional learning. In contrast to human experiments, electrophysiological recordings in the hippocampus of behaving rodents are dominated by theta oscillations reflecting volitional movement, which has been linked to spatial exploration and encoding. This literature makes the surprising cross-species prediction that the human hippocampal theta rhythm supports memory by coordinating exploratory movements in the service of self-directed learning. We examined the links between theta, spatial exploration, and memory encoding by designing an interactive human spatial navigation paradigm combined with multimodal neuroimaging. We used both non-invasive whole-head Magnetoencephalography (MEG to look at theta oscillations and Functional Magnetic Resonance Imaging (fMRI to look at brain regions associated with volitional movement and learning. We found that theta power increases during the self-initiation of virtual movement, additionally correlating with subsequent memory performance and environmental familiarity. Performance-related hippocampal theta increases were observed during a static pre-navigation retrieval phase, where planning for subsequent navigation occurred. Furthermore, periods of the task showing movement-related theta increases showed decreased fMRI activity in the parahippocampus and increased activity in the hippocampus and other brain regions that strikingly overlap with the previously observed volitional learning network (the reverse pattern was seen for stationary periods. These fMRI changes also correlated with participant's performance. Our findings suggest that the human hippocampal theta rhythm supports memory by coordinating

  12. The physiological period length of the human circadian clock in vivo is directly proportional to period in human fibroblasts.

    Directory of Open Access Journals (Sweden)

    Lucia Pagani

    Full Text Available BACKGROUND: Diurnal behavior in humans is governed by the period length of a circadian clock in the suprachiasmatic nuclei of the brain hypothalamus. Nevertheless, the cell-intrinsic mechanism of this clock is present in most cells of the body. We have shown previously that for individuals of extreme chronotype ("larks" and "owls", clock properties measured in human fibroblasts correlated with extreme diurnal behavior. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have measured circadian period in human primary fibroblasts taken from normal individuals and, for the first time, compared it directly with physiological period measured in vivo in the same subjects. Human physiological period length was estimated via the secretion pattern of the hormone melatonin in two different groups of sighted subjects and one group of totally blind subjects, each using different methods. Fibroblast period length was measured via cyclical expression of a lentivirally delivered circadian reporter. Within each group, a positive linear correlation was observed between circadian period length in physiology and in fibroblast gene expression. Interestingly, although blind individuals showed on average the same fibroblast clock properties as sighted ones, their physiological periods were significantly longer. CONCLUSIONS/SIGNIFICANCE: We conclude that the period of human circadian behaviour is mostly driven by cellular clock properties in normal individuals and can be approximated by measurement in peripheral cells such as fibroblasts. Based upon differences among sighted and blind subjects, we also speculate that period can be modified by prolonged unusual conditions such as the total light deprivation of blindness.

  13. Eye blinking in an avian species is associated with gaze shifts.

    Science.gov (United States)

    Yorzinski, Jessica L

    2016-08-30

    Even when animals are actively monitoring their environment, they lose access to visual information whenever they blink. They can strategically time their blinks to minimize information loss and improve visual functioning but we have little understanding of how this process operates in birds. This study therefore examined blinking in freely-moving peacocks (Pavo cristatus) to determine the relationship between their blinks, gaze shifts, and context. Peacocks wearing a telemetric eye-tracker were exposed to a taxidermy predator (Vulpes vulpes) and their blinks and gaze shifts were recorded. Peacocks blinked during the majority of their gaze shifts, especially when gaze shifts were large, thereby timing their blinks to coincide with periods when visual information is already suppressed. They inhibited their blinks the most when they exhibited high rates of gaze shifts and were thus highly alert. Alternative hypotheses explaining the link between blinks and gaze shifts are discussed.

  14. Gazes and Bodies in the Pornographies of Desire

    Directory of Open Access Journals (Sweden)

    Mirko Lino

    2013-06-01

    Full Text Available Il saggio propone una lettura sociale della pornografia cinematografica usando la categoria dello sguardo e le sue declinazioni di genere. Partendo dal famoso saggio di Laura Mulvey, Visual Pleasure and Narrative Cinema (1975, si sposterà il centro dell’analisi dal cinema narrativo tradizionale al cinema pornografico, considerando quest’ultimo un modello che fa contrappunto al voyeurismo dello sguardo maschile (male gaze che la Mulvey riscontrava in alcuni film di Sternberg e di Hitckcock. Per dimostrare la natura contrappuntistica del cinema pornografico si metterà a confronto la medesima messa in scena di uno sguardo che desidera in due film molto differenti tra loro, Rear Window (1954 di Hitchcock e Behind the Green Door (1972 dei fratelli Mitchell. La natura contrappuntistica del porn movie si rintraccia anche nel dialogo che instaura con il cinema mainstream riguardo ai limiti del visibile in materia sessuale. Infine, la pornografia soddisfa la rappresentazione del desiderio delle altre identità di genere, mettendo in scena tipologie di sguardo adeguate – female gaze e queer gaze –, che diventano presto strumenti per una affermazione sociale della diversità sessuali.

  15. Direct evidence that the VEGF-specific antibody bevacizumab has antivascular effects in human rectal cancer

    Science.gov (United States)

    Willett, Christopher G; Boucher, Yves; di Tomaso, Emmanuelle; Duda, Dan G; Munn, Lance L; Tong, Ricky T; Chung, Daniel C; Sahani, Dushyant V; Kalva, Sanjeeva P; Kozin, Sergey V; Mino, Mari; Cohen, Kenneth S; Scadden, David T; Hartford, Alan C; Fischman, Alan J; Clark, Jeffrey W; Ryan, David P; Zhu, Andrew X; Blaszkowsky, Lawrence S; Chen, Helen X; Shellito, Paul C; Lauwers, Gregory Y; Jain, Rakesh K

    2009-01-01

    The effects of vascular endothelial growth factor (VEGF) blockade on the vascular biology of human tumors are not known. Here we show here that a single infusion of the VEGF-specific antibody bevacizumab decreases tumor perfusion, vascular volume, microvascular density, interstitial fluid pressure and the number of viable, circulating endothelial and progenitor cells, and increases the fraction of vessels with pericyte coverage in rectal carcinoma patients. These data indicate that VEGF blockade has a direct and rapid antivascular effect in human tumors. PMID:14745444

  16. Subjects and Objects of the Embodied Gaze: Abbas Kiarostami and the Real of the Individual Perspective

    OpenAIRE

    Gyenge Zsolt

    2016-01-01

    It is widely accepted that Abbas Kiarostami’s cinema revolves around the representation of the gaze. Many critics argue that he should be considered a late modernist who repeats the self-reflexive gestures of modernist European cinema decades after they were first introduced. The present paper will contradict this assertion by investigating the problematic of the Kiarostamian gaze and analyzing the perceptual side of the act of looking. I will argue that instead of focusing on the gaze of the...

  17. Direct electrical stimulation of human cortex evokes high gamma activity that predicts conscious somatosensory perception

    Science.gov (United States)

    Muller, Leah; Rolston, John D.; Fox, Neal P.; Knowlton, Robert; Rao, Vikram R.; Chang, Edward F.

    2018-04-01

    Objective. Direct electrical stimulation (DES) is a clinical gold standard for human brain mapping and readily evokes conscious percepts, yet the neurophysiological changes underlying these percepts are not well understood. Approach. To determine the neural correlates of DES, we stimulated the somatosensory cortex of ten human participants at frequency-amplitude combinations that both elicited and failed to elicit conscious percepts, meanwhile recording neural activity directly surrounding the stimulation site. We then compared the neural activity of perceived trials to that of non-perceived trials. Main results. We found that stimulation evokes distributed high gamma activity, which correlates with conscious perception better than stimulation parameters themselves. Significance. Our findings suggest that high gamma activity is a reliable biomarker for perception evoked by both natural and electrical stimuli.

  18. Fusing Eye-gaze and Speech Recognition for Tracking in an Automatic Reading Tutor

    DEFF Research Database (Denmark)

    Rasmussen, Morten Højfeldt; Tan, Zheng-Hua

    2013-01-01

    In this paper we present a novel approach for automatically tracking the reading progress using a combination of eye-gaze tracking and speech recognition. The two are fused by first generating word probabilities based on eye-gaze information and then using these probabilities to augment the langu......In this paper we present a novel approach for automatically tracking the reading progress using a combination of eye-gaze tracking and speech recognition. The two are fused by first generating word probabilities based on eye-gaze information and then using these probabilities to augment...

  19. Loss of urban forest canopy and the related effects on soundscape and human directed attention

    Science.gov (United States)

    Laverne, Robert James Paul

    The specific questions addressed in this research are: Will the loss of trees in residential neighborhoods result in a change to the local soundscape? The investigation of this question leads to a related inquiry: Do the sounds of the environment in which a person is present affect their directed attention?. An invasive insect pest, the Emerald Ash Borer (Agrilus planipennis ), is killing millions of ash trees (genus Fraxinus) throughout North America. As the loss of tree canopy occurs, urban ecosystems change (including higher summer temperatures, more stormwater runoff, and poorer air quality) causing associated changes to human physical and mental health. Previous studies suggest that conditions in urban environments can result in chronic stress in humans and fatigue to directed attention, which is the ability to focus on tasks and to pay attention. Access to nature in cities can help refresh directed attention. The sights and sounds associated with parks, open spaces, and trees can serve as beneficial counterbalances to the irritating conditions associated with cities. This research examines changes to the quantity and quality of sounds in Arlington Heights, Illinois. A series of before-and-after sound recordings were gathered as trees died and were removed between 2013 and 2015. Comparison of recordings using the Raven sound analysis program revealed significant differences in some, but not all measures of sound attributes as tree canopy decreased. In general, more human-produced mechanical sounds (anthrophony) and fewer sounds associated with weather (geophony) were detected. Changes in sounds associated with animals (biophony) varied seasonally. Monitoring changes in the proportions of anthrophony, biophony and geophony can provide insight into changes in biodiversity, environmental health, and quality of life for humans. Before-tree-removal and after-tree-removal sound recordings served as the independent variable for randomly-assigned human volunteers as

  20. Rapid, Directed Differentiation of Retinal Pigment Epithelial Cells from Human Embryonic or Induced Pluripotent Stem Cells

    OpenAIRE

    Foltz, LP; Clegg, DO

    2017-01-01

    We describe a robust method to direct the differentiation of pluripotent stem cells into retinal pigment epithelial cells (RPE). The purpose of providing a detailed and thorough protocol is to clearly demonstrate each step and to make this readily available to researchers in the field. This protocol results in a homogenous layer of RPE with minimal or no manual dissection needed. The method presented here has been shown to be effective for induced pluripotent stem cells (iPSC) and human embry...

  1. mTORC1 directly phosphorylates and regulates human MAF1.

    OpenAIRE

    Michels Annemieke A; Robitaille Aaron M; Buczynski-Ruchonnet Diane; Hodroj Wassim; Reina Jaime H; Hall Michael N; Hernandez Nouria

    2010-01-01

    mTORC1 is a central regulator of growth in response to nutrient availability, but few direct targets have been identified. RNA polymerase (pol) III produces a number of essential RNA molecules involved in protein synthesis, RNA maturation, and other processes. Its activity is highly regulated, and deregulation can lead to cell transformation. The human phosphoprotein MAF1 becomes dephosphorylated and represses pol III transcription after various stresses, but neither the significance of the p...

  2. Direct visualization of lipid domains in human skin stratum corneum's lipid membranes

    DEFF Research Database (Denmark)

    Plasencia, I; Norlen, Lars; Bagatolli, Luis

    2007-01-01

    scanning calorimetry, fluorescence spectroscopy, and two-photon excitation and laser scanning confocal fluorescence microscopy. Here we show that hydrated bilayers of human skin stratum corneum lipids express a giant sponge-like morphology with dimensions corresponding to the global three......-dimensional morphology of the stratum corneum extracellular space. These structures can be directly visualized using the aforementioned fluorescence microscopy techniques. At skin physiological temperatures (28 degrees C-32 degrees C), the phase state of these hydrated bilayers correspond microscopically (radial...

  3. Direct microcomputer controlled determination of zinc in human serum by flow injection atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Nielsen, Bent; Jensen, Arne

    1986-01-01

    A procedure is described for the direct determination of zinc in human serum by fully automated, microcomputer controlled flow injection atomic absorption spectrometry (Fl-AAS). The Fl system is pumpless, using the negative pressure created by the nebuliser. It only consists of a three-way valve......, programmable from the microcomputer, to control the sample volume. No pre-treatment of the samples is necessary. The limit of detection is 0.14 mg l–1, and only small amounts of serum (

  4. Self-directed learning in gross human anatomy: assessment outcomes and student perceptions.

    Science.gov (United States)

    Smythe, Gayle; Hughes, Diane

    2008-01-01

    Speech pathology students enrolled in a lecture-based gross human anatomy program completed two out of nine topics in self-directed mode. Student performance in quizzes was compared for the two modes, and the students completed questionnaires on their perceptions of the self-directed mode of delivery. Students performed as well in the first self-directed topic as they did in lecture-based material, but performance declined significantly on the second self-directed topic. Correlations showed that students who performed well in lecture-based topics also performed well on self-directed topics. The major issues that arose in the student questionnaires were primarily related to the amount of content in the topics and the length of time required for completion. We conclude that there is a strong need for appropriate design of distance education materials to reflect student perceptions of length, content, and time investment, and more importantly that there is a need to ensure extensive communication and support of students studying in distance education/self-directed modes for the first time.

  5. A preliminary study to understand tacit knowledge and visual routines of medical experts through gaze tracking.

    Science.gov (United States)

    Anderson, Blake; Shyu, Chi-Ren

    2010-11-13

    Many decisions made by medical experts are based on scans from advanced imaging technologies. Interpreting a medical image is a trained, systematic procedure and an excellent target for identifying potential visual routines through image informatics. These visual routines derived from experts contain many clues about visual knowledge and its representation. This study uses an inexpensive webcam-based gaze tracking method to collect data from multiple technologists' survey of medical and non-medical images. Through computational analysis of the results, we expect to provide insight into the behaviors and properties related to medical visual routines. Discovering the visual processes associated with medical images will help us recognize and understand the tacit knowledge gained from extensive experience with medical imagery. These expert routines could potentially be used to reduce medical error, train new experts, and provide an understanding of the human visual system in medicine.

  6. Gamma irradiation does not induce detectable changes in DNA methylation directly following exposure of human cells.

    Directory of Open Access Journals (Sweden)

    Christoph Lahtz

    Full Text Available Environmental chemicals and radiation have often been implicated in producing alterations of the epigenome thus potentially contributing to cancer and other diseases. Ionizing radiation, released during accidents at nuclear power plants or after atomic bomb explosions, is a potentially serious health threat for the exposed human population. This type of high-energy radiation causes DNA damage including single- and double-strand breaks and induces chromosomal rearrangements and mutations, but it is not known if ionizing radiation directly induces changes in the epigenome of irradiated cells. We treated normal human fibroblasts and normal human bronchial epithelial cells with different doses of γ-radiation emitted from a cesium 137 ((137Cs radiation source. After a seven-day recovery period, we analyzed global DNA methylation patterns in the irradiated and control cells using the methylated-CpG island recovery assay (MIRA in combination with high-resolution microarrays. Bioinformatics analysis revealed only a small number of potential methylation changes with low fold-difference ratios in the irradiated cells. These minor methylation differences seen on the microarrays could not be verified by COBRA (combined bisulfite restriction analysis or bisulfite sequencing of selected target loci. Our study shows that acute γ-radiation treatment of two types of human cells had no appreciable direct effect on DNA cytosine methylation patterns in exposed cells.

  7. Direct Neural Conversion from Human Fibroblasts Using Self-Regulating and Nonintegrating Viral Vectors

    Directory of Open Access Journals (Sweden)

    Shong Lau

    2014-12-01

    Full Text Available Summary: Recent findings show that human fibroblasts can be directly programmed into functional neurons without passing via a proliferative stem cell intermediate. These findings open up the possibility of generating subtype-specific neurons of human origin for therapeutic use from fetal cell, from patients themselves, or from matched donors. In this study, we present an improved system for direct neural conversion of human fibroblasts. The neural reprogramming genes are regulated by the neuron-specific microRNA, miR-124, such that each cell turns off expression of the reprogramming genes once the cell has reached a stable neuronal fate. The regulated system can be combined with integrase-deficient vectors, providing a nonintegrative and self-regulated conversion system that rids problems associated with the integration of viral transgenes into the host genome. These modifications make the system suitable for clinical use and therefore represent a major step forward in the development of induced neurons for cell therapy. : Lau et al. now use miRNA targeting to build a self-regulating neural conversion system. Combined with nonintegrating vectors, this system can efficiently drive conversion of human fibroblasts into functional induced neurons (iNs suitable for clinical applications.

  8. New sensitive direct radioimmunoassay for human plasma renin and its clinical application

    International Nuclear Information System (INIS)

    Higaki, J.; Ogihara, T.; Imai, N.; Kumahara, Y.; Hontani, S.; Nishiura, M.; Ogawa, H.; Hirose, S.; Murakami, K.

    1984-01-01

    A new sensitive direct radioimmunoassay for human plasma renin has been developed. Renin was purified from Haas' preparation utilizing a pepstatin-C 6 -Sepharose affinity chromatography. Antiserum, prepared by immunizing rabbits with the purified renin, was used for the direct radioimmunoassay at a final dilution of 1:30,000. The antibody was specific for human renal and plasma renin, but did not cross-react with cathepsin D, trypsin, or renins of mouse, dog, and rat. Radioimmunoassay was performed by the double antibody technique using the delayed tracer addition method. In this method, a standard curve was obtained over a range from 0.2 to 8.0 ng/ml. The values from this assay correlated well with total renin activity measured as the generation rate of angiotensin I after trypsin activation, but correlated weakly with active renin activity. This finding disclosed that both active and inactive renin were detected by this method. In normal participants, plasma renin concentration determined by direct radioimmunoassay was increased by standing and furosemide injection. The plasma renin concentration determined by direct radioimmunoassay of patients with essential hypertension was not significantly different from values in normal controls. The values were higher in patients with renovascular hypertension, malignant hypertension and Bartter's syndrome, but lower in patients with primary aldosteronism than in normal controls. 20 references, 7 figures

  9. Assessing Impact Direction in 3-point Bending of Human Femora: Incomplete Butterfly Fractures and Fracture Surfaces,.

    Science.gov (United States)

    Isa, Mariyam I; Fenton, Todd W; Deland, Trevor; Haut, Roger C

    2018-01-01

    Current literature associates bending failure with butterfly fracture, in which fracture initiates transversely at the tensile surface of a bent bone and branches as it propagates toward the impact surface. The orientation of the resulting wedge fragment is often considered diagnostic of impact direction. However, experimental studies indicate bending does not always produce complete butterfly fractures or produces wedge fragments variably in tension or compression, precluding their use in interpreting directionality. This study reports results of experimental 3-point bending tests on thirteen unembalmed human femora. Complete fracture patterns varied following bending failure, but incomplete fractures and fracture surface characteristics were observed in all impacted specimens. A flat, billowy fracture surface was observed in tension, while jagged, angular peaks were observed in compression. Impact direction was accurately reconstructed using incomplete tension wedge butterfly fractures and tension and compression fracture surface criteria in all thirteen specimens. © 2017 American Academy of Forensic Sciences.

  10. The Degradation Interface of Magnesium Based Alloys in Direct Contact with Human Primary Osteoblast Cells.

    Directory of Open Access Journals (Sweden)

    Nezha Ahmad Agha

    Full Text Available Magnesium alloys have been identified as a new generation material of orthopaedic implants. In vitro setups mimicking physiological conditions are promising for material / degradation analysis prior to in vivo studies however the direct influence of cell on the degradation mechanism has never been investigated. For the first time, the direct, active, influence of human primary osteoblasts on magnesium-based materials (pure magnesium, Mg-2Ag and Mg-10Gd alloys is studied for up to 14 days. Several parameters such as composition of the degradation interface (directly beneath the cells are analysed with a scanning electron microscope equipped with energy dispersive X-ray and focused ion beam. Furthermore, influence of the materials on cell metabolism is examined via different parameters like active mineralisation process. The results are highlighting the influences of the selected alloying element on the initial cells metabolic activity.

  11. The Degradation Interface of Magnesium Based Alloys in Direct Contact with Human Primary Osteoblast Cells.

    Science.gov (United States)

    Ahmad Agha, Nezha; Willumeit-Römer, Regine; Laipple, Daniel; Luthringer, Bérengère; Feyerabend, Frank

    2016-01-01

    Magnesium alloys have been identified as a new generation material of orthopaedic implants. In vitro setups mimicking physiological conditions are promising for material / degradation analysis prior to in vivo studies however the direct influence of cell on the degradation mechanism has never been investigated. For the first time, the direct, active, influence of human primary osteoblasts on magnesium-based materials (pure magnesium, Mg-2Ag and Mg-10Gd alloys) is studied for up to 14 days. Several parameters such as composition of the degradation interface (directly beneath the cells) are analysed with a scanning electron microscope equipped with energy dispersive X-ray and focused ion beam. Furthermore, influence of the materials on cell metabolism is examined via different parameters like active mineralisation process. The results are highlighting the influences of the selected alloying element on the initial cells metabolic activity.

  12. Direct observation of glycogen synthesis in human muscle with 13C NMR

    International Nuclear Information System (INIS)

    Jue, T.; Rothman, D.L.; Shulman, G.I.; Tavitian, B.A.; DeFronzo, R.A.; Shulman, R.G.

    1989-01-01

    On the basis of previous indirect measurements, skeletal muscle has been implicated as the major site of glucose uptake and it has been suggested that muscle glycogen formation is the dominant pathway. However, direct measurements of the rates of glycogen synthesis have not been possible by previous techniques. The authors have developed 13 C NMR methods to measure directly the rate of human muscle glycogen formation from infused, isotopically labeled [1- 13 C]glucose. They show that under conditions of imposed hyperglycemia and hyperinsulinemia, a majority of the infused glucose was converted to muscle glycogen in a normal man. This directly shows that muscle is the major site of glucose disposal under these conditions, and provides quantitation of the glucose flux to muscle glycogen

  13. Probabilistic Mapping of Human Visual Attention from Head Pose Estimation

    Directory of Open Access Journals (Sweden)

    Andrea Veronese

    2017-10-01

    Full Text Available Effective interaction between a human and a robot requires the bidirectional perception and interpretation of actions and behavior. While actions can be identified as a directly observable activity, this might not be sufficient to deduce actions in a scene. For example, orienting our face toward a book might suggest the action toward “reading.” For a human observer, this deduction requires the direction of gaze, the object identified as a book and the intersection between gaze and book. With this in mind, we aim to estimate and map human visual attention as directed to a scene, and assess how this relates to the detection of objects and their related actions. In particular, we consider human head pose as measurement to infer the attention of a human engaged in a task and study which prior knowledge should be included in such a detection system. In a user study, we show the successful detection of attention to objects in a typical office task scenario (i.e., reading, working with a computer, studying an object. Our system requires a single external RGB camera for head pose measurements and a pre-recorded 3D point cloud of the environment.

  14. Oxytocin receptor gene polymorphisms are associated with human directed social behavior in dogs (Canis familiaris.

    Directory of Open Access Journals (Sweden)

    Anna Kis

    Full Text Available The oxytocin system has a crucial role in human sociality; several results prove that polymorphisms of the oxytocin receptor gene are related to complex social behaviors in humans. Dogs' parallel evolution with humans and their adaptation to the human environment has made them a useful species to model human social interactions. Previous research indicates that dogs are eligible models for behavioral genetic research, as well. Based on these previous findings, our research investigated associations between human directed social behaviors and two newly described (-212AG, 19131AG and one known (rs8679684 single nucleotide polymorphisms (SNPs in the regulatory regions (5' and 3' UTR of the oxytocin receptor gene in German Shepherd (N = 104 and Border Collie (N = 103 dogs. Dogs' behavior traits have been estimated in a newly developed test series consisting of five episodes: Greeting by a stranger, Separation from the owner, Problem solving, Threatening approach, Hiding of the owner. Buccal samples were collected and DNA was isolated using standard protocols. SNPs in the 3' and 5' UTR regions were analyzed by polymerase chain reaction based techniques followed by subsequent electrophoresis analysis. The gene-behavior association analysis suggests that oxytocin receptor gene polymorphisms have an impact in both breeds on (i proximity seeking towards an unfamiliar person, as well as their owner, and on (ii how friendly dogs behave towards strangers, although the mediating molecular regulatory mechanisms are yet unknown. Based on these results, we conclude that similarly to humans, the social behavior of dogs towards humans is influenced by the oxytocin system.

  15. Gazing and Typing Activities during Translation

    DEFF Research Database (Denmark)

    Carl, Michael; Kay, Martin

    2011-01-01

    The paper investigates the notion of Translation Units (TUs) from a cognitive angle. A TU is defined as the translator’s focus of attention at a time. Since attention can be directed towards source text (ST) understanding and/or target text (TT) production, we analyze the activity data...... of a 160 word text we find major differences between students and professionals: Experienced professional translators are better able to divide their attention in parallel on ST reading (comprehension) and TT production, while students operate more in an alternating mode where they either read the ST...

  16. Accuracy of outcome anticipation, but not gaze behavior, differs against left- and right-handed penalties in team-handball goalkeeping

    Directory of Open Access Journals (Sweden)

    Florian eLoffing

    2015-12-01

    Full Text Available Low perceptual familiarity with relatively rarer left-handed as opposed to more common right-handed individuals may result in athletes’ poorer ability to anticipate the former’s action intentions. Part of such left-right asymmetry in visual anticipation could be due to an inefficient gaze strategy during confrontation with left-handed individuals. To exemplify, observers may not mirror their gaze when viewing left- vs. right-handed actions but preferentially fixate on an opponent’s right body side, irrespective of an opponent’s handedness, owing to the predominant exposure to right-handed actions. So far empirical verification of such assumption, however, is lacking. Here we report on an experiment where team-handball goalkeepers’ and non-goalkeepers’ gaze behavior was recorded while they predicted throw direction of left- and right-handed seven-meter penalties shown as videos on a computer monitor. As expected, goalkeepers were considerably more accurate than non-goalkeepers and prediction was better against right- than left-handed penalties. However, there was no indication of differences in gaze measures (i.e., number of fixations, overall and final fixation duration, time-course of horizontal or vertical fixation deviation as a function of skill group or the penalty-takers’ handedness. Findings suggest that inferior anticipation of left-handed compared to right-handed individuals’ action intentions may not be associated with misalignment in gaze behavior. Rather, albeit looking similarly, accuracy differences could be due to observers’ differential ability of picking up and interpreting the visual information provided by left- vs. right-handed movements.

  17. Accuracy of Outcome Anticipation, But Not Gaze Behavior, Differs Against Left- and Right-Handed Penalties in Team-Handball Goalkeeping

    Science.gov (United States)

    Loffing, Florian; Sölter, Florian; Hagemann, Norbert; Strauss, Bernd

    2015-01-01

    Low perceptual familiarity with relatively rarer left-handed as opposed to more common right-handed individuals may result in athletes' poorer ability to anticipate the former's action intentions. Part of such left-right asymmetry in visual anticipation could be due to an inefficient gaze strategy during confrontation with left-handed individuals. To exemplify, observers may not mirror their gaze when viewing left- vs. right-handed actions but preferentially fixate on an opponent's right body side, irrespective of an opponent's handedness, owing to the predominant exposure to right-handed actions. So far empirical verification of such assumption, however, is lacking. Here we report on an experiment where team-handball goalkeepers' and non-goalkeepers' gaze behavior was recorded while they predicted throw direction of left- and right-handed 7-m penalties shown as videos on a computer monitor. As expected, goalkeepers were considerably more accurate than non-goalkeepers and prediction was better against right- than left-handed penalties. However, there was no indication of differences in gaze measures (i.e., number of fixations, overall and final fixation duration, time-course of horizontal or vertical fixation deviation) as a function of skill group or the penalty-takers' handedness. Findings suggest that inferior anticipation of left-handed compared to right-handed individuals' action intentions may not be associated with misalignment in gaze behavior. Rather, albeit looking similarly, accuracy differences could be due to observers' differential ability of picking up and interpreting the visual information provided by left- vs. right-handed movements. PMID:26648887

  18. Accuracy of Outcome Anticipation, But Not Gaze Behavior, Differs Against Left- and Right-Handed Penalties in Team-Handball Goalkeeping.

    Science.gov (United States)

    Loffing, Florian; Sölter, Florian; Hagemann, Norbert; Strauss, Bernd

    2015-01-01

    Low perceptual familiarity with relatively rarer left-handed as opposed to more common right-handed individuals may result in athletes' poorer ability to anticipate the former's action intentions. Part of such left-right asymmetry in visual anticipation could be due to an inefficient gaze strategy during confrontation with left-handed individuals. To exemplify, observers may not mirror their gaze when viewing left- vs. right-handed actions but preferentially fixate on an opponent's right body side, irrespective of an opponent's handedness, owing to the predominant exposure to right-handed actions. So far empirical verification of such assumption, however, is lacking. Here we report on an experiment where team-handball goalkeepers' and non-goalkeepers' gaze behavior was recorded while they predicted throw direction of left- and right-handed 7-m penalties shown as videos on a computer monitor. As expected, goalkeepers were considerably more accurate than non-goalkeepers and prediction was better against right- than left-handed penalties. However, there was no indication of differences in gaze measures (i.e., number of fixations, overall and final fixation duration, time-course of horizontal or vertical fixation deviation) as a function of skill group or the penalty-takers' handedness. Findings suggest that inferior anticipation of left-handed compared to right-handed individuals' action intentions may not be associated with misalignment in gaze behavior. Rather, albeit looking similarly, accuracy differences could be due to observers' differential ability of picking up and interpreting the visual information provided by left- vs. right-handed movements.

  19. Gaze training enhances laparoscopic technical skill acquisition and multi-tasking performance: a randomized, controlled study.

    Science.gov (United States)

    Wilson, Mark R; Vine, Samuel J; Bright, Elizabeth; Masters, Rich S W; Defriend, David; McGrath, John S

    2011-12-01

    The operating room environment is replete with stressors and distractions that increase the attention demands of what are already complex psychomotor procedures. Contemporary research in other fields (e.g., sport) has revealed that gaze training interventions may support the development of robust movement skills. This current study was designed to examine the utility of gaze training for technical laparoscopic skills and to test performance under multitasking conditions. Thirty medical trainees with no laparoscopic experience were divided randomly into one of three treatment groups: gaze trained (GAZE), movement trained (MOVE), and discovery learning/control (DISCOVERY). Participants were fitted with a Mobile Eye gaze registration system, which measures eye-line of gaze at 25 Hz. Training consisted of ten repetitions of the "eye-hand coordination" task from the LAP Mentor VR laparoscopic surgical simulator while receiving instruction and video feedback (specific to each treatment condition). After training, all participants completed a control test (designed to assess learning) and a multitasking transfer test, in which they completed the procedure while performing a concurrent tone counting task. Not only did the GAZE group learn more quickly than the MOVE and DISCOVERY groups (faster completion times in the control test), but the performance difference was even more pronounced when multitasking. Differences in gaze control (target locking fixations), rather than tool movement measures (tool path length), underpinned this performance advantage for GAZE training. These results suggest that although the GAZE intervention focused on training gaze behavior only, there were indirect benefits for movement behaviors and performance efficiency. Additionally, focusing on a single external target when learning, rather than on complex movement patterns, may have freed-up attentional resources that could be applied to concurrent cognitive tasks.

  20. mTORC1 directly phosphorylates and regulates human MAF1.

    Science.gov (United States)

    Michels, Annemieke A; Robitaille, Aaron M; Buczynski-Ruchonnet, Diane; Hodroj, Wassim; Reina, Jaime H; Hall, Michael N; Hernandez, Nouria

    2010-08-01

    mTORC1 is a central regulator of growth in response to nutrient availability, but few direct targets have been identified. RNA polymerase (pol) III produces a number of essential RNA molecules involved in protein synthesis, RNA maturation, and other processes. Its activity is highly regulated, and deregulation can lead to cell transformation. The human phosphoprotein MAF1 becomes dephosphorylated and represses pol III transcription after various stresses, but neither the significance of the phosphorylations nor the kinase involved is known. We find that human MAF1 is absolutely required for pol III repression in response to serum starvation or TORC1 inhibition by rapamycin or Torin1. The protein is phosphorylated mainly on residues S60, S68, and S75, and this inhibits its pol III repression function. The responsible kinase is mTORC1, which phosphorylates MAF1 directly. Our results describe molecular mechanisms by which mTORC1 controls human MAF1, a key repressor of RNA polymerase III transcription, and add a new branch to the signal transduction cascade immediately downstream of TORC1.

  1. mTORC1 Directly Phosphorylates and Regulates Human MAF1▿

    Science.gov (United States)

    Michels, Annemieke A.; Robitaille, Aaron M.; Buczynski-Ruchonnet, Diane; Hodroj, Wassim; Reina, Jaime H.; Hall, Michael N.; Hernandez, Nouria

    2010-01-01

    mTORC1 is a central regulator of growth in response to nutrient availability, but few direct targets have been identified. RNA polymerase (pol) III produces a number of essential RNA molecules involved in protein synthesis, RNA maturation, and other processes. Its activity is highly regulated, and deregulation can lead to cell transformation. The human phosphoprotein MAF1 becomes dephosphorylated and represses pol III transcription after various stresses, but neither the significance of the phosphorylations nor the kinase involved is known. We find that human MAF1 is absolutely required for pol III repression in response to serum starvation or TORC1 inhibition by rapamycin or Torin1. The protein is phosphorylated mainly on residues S60, S68, and S75, and this inhibits its pol III repression function. The responsible kinase is mTORC1, which phosphorylates MAF1 directly. Our results describe molecular mechanisms by which mTORC1 controls human MAF1, a key repressor of RNA polymerase III transcription, and add a new branch to the signal transduction cascade immediately downstream of TORC1. PMID:20516213

  2. Direct RNA-based detection of CTX-M β-lactamases in human blood samples.

    Science.gov (United States)

    Stein, Claudia; Makarewicz, Oliwia; Pfeifer, Yvonne; Brandt, Christian; Pletz, Mathias W

    2015-05-01

    Bloodstream infections with ESBL-producers are associated with increased mortality, which is due to delayed appropriate treatment resulting in clinical failure. Current routine diagnostics for detection of bloodstream infections consists of blood culture followed by species identification and susceptibility testing. In attempts to improve and accelerate diagnostic procedures, PCR-based methods have been developed. These methods focus on species identification covering only a limited number of ESBL coding genes. Therefore, they fail to cover the steadily further evolving genetic diversity of clinically relevant β-lactamases. We have recently designed a fast and novel RNA targeting method to detect and specify CTX-M alleles from bacterial cultures, based on an amplification-pyrosequencing approach. We further developed this assay towards a diagnostic tool for clinical use and evaluated its sensitivity and specificity when applied directly to human blood samples. An optimized protocol for mRNA isolation allows detection of specific CTX-M groups from as little as 100 CFU/mL blood via reverse transcription, amplification, and pyrosequencing directly from human EDTA blood samples as well as from pre-incubated human blood cultures with a turnaround time for test results of <7 h. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Generation of Directly Converted Human Osteoblasts That Are Free of Exogenous Gene and Xenogenic Protein.

    Science.gov (United States)

    Yamamoto, Kenta; Sato, Yoshiki; Honjo, Kenichi; Ichioka, Hiroaki; Oseko, Fumishige; Sowa, Yoshihiro; Yamamoto, Toshiro; Kanamura, Narisato; Kishida, Tsunao; Mazda, Osam

    2016-11-01

    Generation of osteoblasts from human somatic cells may be applicable in an effective transplantation therapy against bone diseases. Recently we established a procedure to directly convert human fibroblasts into osteoblasts by transducing some transcription factor genes via retroviral vectors. However, retroviral vector-mediated transduction may potentially cause tumor formation from the infected cells, thus a non-viral gene transfection method may be more preferable for preparation of osteoblasts to be used for transplantation therapy. Here, we constructed a plasmid vector encoding Oct4, Osterix, and L-Myc that were an appropriate combination of transcription factors for this purpose. Osteoblast-like phenotypes including high alkaline phosphatase (ALP) activity, bone matrix production and osteoblast-specific gene expression were induced in normal human fibroblasts that were transfected with the plasmid followed by culturing in osteogenic medium. The plasmid-driven directly converted osteoblasts (p-dOBs) were obtained even in the absence of a xenogenic protein. The plasmid vector sequence had fallen out of the p-dOBs. The cells formed deposition of calcified bodies in situ after transplantation into mice. These results strongly suggest that p-dOBs can be put into practical use for a novel cell-based therapy against bone diseases. J. Cell. Biochem. 117: 2538-2545, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Comparison of dogs and humans in visual scanning of social interaction.

    Science.gov (United States)

    Törnqvist, Heini; Somppi, Sanni; Koskela, Aija; Krause, Christina M; Vainio, Outi; Kujala, Miiamaaria V

    2015-09-01

    Previous studies have demonstrated similarities in gazing behaviour of dogs and humans, but comparisons under similar conditions are rare, and little is known about dogs' visual attention to social scenes. Here, we recorded the eye gaze of dogs while they viewed images containing two humans or dogs either interacting socially or facing away: the results were compared with equivalent data measured from humans. Furthermore, we compared the gazing behaviour of two dog and two human populations with different social experiences: family and kennel dogs; dog experts and non-experts. Dogs' gazing behaviour was similar to humans: both species gazed longer at the actors in social interaction than in non-social images. However, humans gazed longer at the actors in dog than human social interaction images, whereas dogs gazed longer at the actors in human than dog social interaction images. Both species also made more saccades between actors in images representing non-conspecifics, which could indicate that processing social interaction of non-conspecifics may be more demanding. Dog experts and non-experts viewed the images very similarly. Kennel dogs viewed images less than family dogs, but otherwise their gazing behaviour did not differ, indicating that the basic processing of social stimuli remains similar regardless of social experiences.

  5. The effect of atomoxetine on random and directed exploration in humans.

    Science.gov (United States)

    Warren, Christopher M; Wilson, Robert C; van der Wee, Nic J; Giltay, Eric J; van Noorden, Martijn S; Cohen, Jonathan D; Nieuwenhuis, Sander

    2017-01-01

    The adaptive regulation of the trade-off between pursuing a known reward (exploitation) and sampling lesser-known options in search of something better (exploration) is critical for optimal performance. Theory and recent empirical work suggest that humans use at least two strategies for solving this dilemma: a directed strategy in which choices are explicitly biased toward information seeking, and a random strategy in which decision noise leads to exploration by chance. Here we examined the hypothesis that random exploration is governed by the neuromodulatory locus coeruleus-norepinephrine system. We administered atomoxetine, a norepinephrine transporter blocker that increases extracellular levels of norepinephrine throughout the cortex, to 22 healthy human participants in a double-blind crossover design. We examined the effect of treatment on performance in a gambling task designed to produce distinct measures of directed exploration and random exploration. In line with our hypothesis we found an effect of atomoxetine on random, but not directed exploration. However, contrary to expectation, atomoxetine reduced rather than increased random exploration. We offer three potential explanations of our findings, involving the non-linear relationship between tonic NE and cognitive performance, the interaction of atomoxetine with other neuromodulators, and the possibility that atomoxetine affected phasic norepinephrine activity more so than tonic norepinephrine activity.

  6. Direct conversion of human fibroblasts into functional osteoblasts by defined factors.

    Science.gov (United States)

    Yamamoto, Kenta; Kishida, Tsunao; Sato, Yoshiki; Nishioka, Keisuke; Ejima, Akika; Fujiwara, Hiroyoshi; Kubo, Toshikazu; Yamamoto, Toshiro; Kanamura, Narisato; Mazda, Osam

    2015-05-12

    Osteoblasts produce calcified bone matrix and contribute to bone formation and remodeling. In this study, we established a procedure to directly convert human fibroblasts into osteoblasts by transducing some defined factors and culturing in osteogenic medium. Osteoblast-specific transcription factors, Runt-related transcription factor 2 (Runx2), and Osterix, in combination with Octamer-binding transcription factor 3/4 (Oct4) and L-Myc (RXOL) transduction, converted ∼ 80% of the fibroblasts into osteocalcin-producing cells. The directly converted osteoblasts (dOBs) induced by RXOL displayed a similar gene expression profile as normal human osteoblasts and contributed to bone repair after transplantation into immunodeficient mice at artificial bone defect lesions. The dOBs expressed endogenous Runx2 and Osterix, and did not require continuous expression of the exogenous genes to maintain their phenotype. Another combination, Oct4 plus L-Myc (OL), also induced fibroblasts to produce bone matrix, but the OL-transduced cells did not express Osterix and exhibited a more distant gene expression profile to osteoblasts compared with RXOL-transduced cells. These findings strongly suggest successful direct reprogramming of fibroblasts into functional osteoblasts by RXOL, a technology that may provide bone regeneration therapy against bone disorders.

  7. Planning Ahead: Object-Directed Sequential Actions Decoded from Human Frontoparietal and Occipitotemporal Networks

    Science.gov (United States)

    Gallivan, Jason P.; Johnsrude, Ingrid S.; Randall Flanagan, J.

    2016-01-01

    Object-manipulation tasks (e.g., drinking from a cup) typically involve sequencing together a series of distinct motor acts (e.g., reaching toward, grasping, lifting, and transporting the cup) in order to accomplish some overarching goal (e.g., quenching thirst). Although several studies in humans have investigated the neural mechanisms supporting the planning of visually guided movements directed toward objects (such as reaching or pointing), only a handful have examined how manipulatory sequences of actions—those that occur after an object has been grasped—are planned and represented in the brain. Here, using event-related functional MRI and pattern decoding methods, we investigated the neural basis of real-object manipulation using a delayed-movement task in which participants first prepared and then executed different object-directed action sequences that varied either in their complexity or final spatial goals. Consistent with previous reports of preparatory brain activity in non-human primates, we found that activity patterns in several frontoparietal areas reliably predicted entire action sequences in advance of movement. Notably, we found that similar sequence-related information could also be decoded from pre-movement signals in object- and body-selective occipitotemporal cortex (OTC). These findings suggest that both frontoparietal and occipitotemporal circuits are engaged in transforming object-related information into complex, goal-directed movements. PMID:25576538

  8. Gaze stability of observers watching Op Art pictures.

    Science.gov (United States)

    Zanker, Johannes M; Doyle, Melanie; Robin, Walker

    2003-01-01

    It has been the matter of some debate why we can experience vivid dynamic illusions when looking at static pictures composed from simple black and white patterns. The impression of illusory motion is particularly strong when viewing some of the works of 'Op Artists, such as Bridget Riley's painting Fall. Explanations of the illusory motion have ranged from retinal to cortical mechanisms, and an important role has been attributed to eye movements. To assess the possible contribution of eye movements to the illusory-motion percept we studied the strength of the illusion under different viewing conditions, and analysed the gaze stability of observers viewing the Riley painting and control patterns that do not produce the illusion. Whereas the illusion was reduced, but not abolished, when watching the painting through a pinhole, which reduces the effects of accommodation, it was not perceived in flash afterimages, suggesting an important role for eye movements in generating the illusion for this image. Recordings of eye movements revealed an abundance of small involuntary saccades when looking at the Riley pattern, despite the fact that gaze was kept within the dedicated fixation region. The frequency and particular characteristics of these rapid eye movements can vary considerably between different observers, but, although there was a tendency for gaze stability to deteriorate while viewing a Riley painting, there was no significant difference in saccade frequency between the stimulus and control patterns. Theoretical considerations indicate that such small image displacements can generate patterns of motion signals in a motion-detector network, which may serve as a simple and sufficient, but not necessarily exclusive, explanation for the illusion. Why such image displacements lead to perceptual results with a group of Op Art and similar patterns, but remain invisible for other stimuli, is discussed.

  9. Mutual Disambiguation of Eye Gaze and Speech for Sight Translation and Reading

    DEFF Research Database (Denmark)

    Kulkarni, Rucha; Jain, Kritika; Bansal, Himanshu

    2013-01-01

    and composition of the two modalities was used for integration. F-measure for Eye-Gaze and Word Accuracy for ASR were used as metrics to evaluate our results. In reading task, we demonstrated a significant improvement in both Eye-Gaze f-measure and speech Word Accuracy. In sight translation task, significant...

  10. Tactile band : accessing gaze signals from the sighted in face-to-face communication

    NARCIS (Netherlands)

    Qiu, S.; Rauterberg, G.W.M.; Hu, J.

    2016-01-01

    Gaze signals, frequently used by the sighted in social interactions as visual cues, are hardly accessible for low-vision and blind people. A concept is proposed to help the blind people access and react to gaze signals in face-to-face communication. 20 blind and low-vision participants were

  11. Attention and Gaze Control in Picture Naming, Word Reading, and Word Categorizing

    Science.gov (United States)

    Roelofs, Ardi

    2007-01-01

    The trigger for shifting gaze between stimuli requiring vocal and manual responses was examined. Participants were presented with picture-word stimuli and left- or right-pointing arrows. They vocally named the picture (Experiment 1), read the word (Experiment 2), or categorized the word (Experiment 3) and shifted their gaze to the arrow to…

  12. Gaze-based interaction with public displays using off-the-shelf components

    DEFF Research Database (Denmark)

    San Agustin, Javier; Hansen, John Paulin; Tall, Martin Henrik

    Eye gaze can be used to interact with high-density information presented on large displays. We have built a system employing off-the-shelf hardware components and open-source gaze tracking software that enables users to interact with an interface displayed on a 55” screen using their eye movement...

  13. Deep Learning-Based Gaze Detection System for Automobile Drivers Using a NIR Camera Sensor

    Directory of Open Access Journals (Sweden)

    Rizwan Ali Naqvi

    2018-02-01

    Full Text Available A paradigm shift is required to prevent the increasing automobile accident deaths that are mostly due to the inattentive behavior of drivers. Knowledge of gaze region can provide valuable information regarding a driver’s point of attention. Accurate and inexpensive gaze classification systems in cars can improve safe driving. However, monitoring real-time driving behaviors and conditions presents some challenges: dizziness due to long drives, extreme lighting variations, glasses reflections, and occlusions. Past studies on gaze detection in cars have been chiefly based on head movements. The margin of error in gaze detection increases when drivers gaze at objects by moving their eyes without moving their heads. To solve this problem, a pupil center corneal reflection (PCCR-based method has been considered. However, the error of accurately detecting the pupil center and corneal reflection center is increased in a car environment due to various environment light changes, reflections on glasses surface, and motion and optical blurring of captured eye image. In addition, existing PCCR-based methods require initial user calibration, which is difficult to perform in a car environment. To address this issue, we propose a deep learning-based gaze detection method using a near-infrared (NIR camera sensor considering driver head and eye movement that does not require any initial user calibration. The proposed system is evaluated on our self-constructed database as well as on open Columbia gaze dataset (CAVE-DB. The proposed method demonstrated greater accuracy than the previous gaze classification methods.

  14. Deep Learning-Based Gaze Detection System for Automobile Drivers Using a NIR Camera Sensor.

    Science.gov (United States)

    Naqvi, Rizwan Ali; Arsalan, Muhammad; Batchuluun, Ganbayar; Yoon, Hyo Sik; Park, Kang Ryoung

    2018-02-03

    A paradigm shift is required to prevent the increasing automobile accident deaths that are mostly due to the inattentive behavior of drivers. Knowledge of gaze region can provide valuable information regarding a driver's point of attention. Accurate and inexpensive gaze classification systems in cars can improve safe driving. However, monitoring real-time driving behaviors and conditions presents some challenges: dizziness due to long drives, extreme lighting variations, glasses reflections, and occlusions. Past studies on gaze detection in cars have been chiefly based on head movements. The margin of error in gaze detection increases when drivers gaze at objects by moving their eyes without moving their heads. To solve this problem, a pupil center corneal reflection (PCCR)-based method has been considered. However, the error of accurately detecting the pupil center and corneal reflection center is increased in a car environment due to various environment light changes, reflections on glasses surface, and motion and optical blurring of captured eye image. In addition, existing PCCR-based methods require initial user calibration, which is difficult to perform in a car environment. To address this issue, we propose a deep learning-based gaze detection method using a near-infrared (NIR) camera sensor considering driver head and eye movement that does not require any initial user calibration. The proposed system is evaluated on our self-constructed database as well as on open Columbia gaze dataset (CAVE-DB). The proposed method demonstrated greater accuracy than the previous gaze classification methods.

  15. It Takes Time and Experience to Learn How to Interpret Gaze in Mentalistic Terms

    Science.gov (United States)

    Leavens, David A.

    2006-01-01

    What capabilities are required for an organism to evince an "explicit" understanding of gaze as a mentalistic phenomenon? One possibility is that mentalistic interpretations of gaze, like concepts of unseen, supernatural beings, are culturally-specific concepts, acquired through cultural learning. These abstract concepts may either require a…

  16. Coding gaze tracking data with chromatic gradients for VR Exposure Therapy

    DEFF Research Database (Denmark)

    Herbelin, Bruno; Grillon, Helena; De Heras Ciechomski, Pablo

    2007-01-01

    This article presents a simple and intuitive way to represent the eye-tracking data gathered during immersive virtual reality exposure therapy sessions. Eye-tracking technology is used to observe gaze movements during vir- tual reality sessions and the gaze-map chromatic gradient coding allows to...... is fully compatible with different VR exposure systems and provides clinically meaningful data....

  17. Gaze Strategies in Skateboard Trick Jumps: Spatiotemporal Constraints in Complex Locomotion

    Science.gov (United States)

    Klostermann, André; Küng, Philip

    2017-01-01

    Purpose: This study aimed to further the knowledge on gaze behavior in locomotion by studying gaze strategies in skateboard jumps of different difficulty that had to be performed either with or without an obstacle. Method: Nine experienced skateboarders performed "Ollie" and "Kickflip" jumps either over an obstacle or over a…

  18. Reading pleasure : Light in August and the theory of the gendered gaze

    NARCIS (Netherlands)

    Visser, [No Value

    1997-01-01

    This article discusses various components of the theory of the gendered gaze, in order to construct a framework for an analysis of how William Faulkner understood and fictionally presented the mechanism of the gaze in Light in August. Linking theory and praxis, this article explores the relationship

  19. Gaze3DFix: Detecting 3D fixations with an ellipsoidal bounding volume.

    Science.gov (United States)

    Weber, Sascha; Schubert, Rebekka S; Vogt, Stefan; Velichkovsky, Boris M; Pannasch, Sebastian

    2017-10-26

    Nowadays, the use of eyetracking to determine 2-D gaze positions is common practice, and several approaches to the detection of 2-D fixations exist, but ready-to-use algorithms to determine eye movements in three dimensions are still missing. Here we present a dispersion-based algorithm with an ellipsoidal bounding volume that estimates 3D fixations. Therefore, 3D gaze points are obtained using a vector-based approach and are further processed with our algorithm. To evaluate the accuracy of our method, we performed experimental studies with real and virtual stimuli. We obtained good congruence between stimulus position and both the 3D gaze points and the 3D fixation locations within the tested range of 200-600 mm. The mean deviation of the 3D fixations from the stimulus positions was 17 mm for the real as well as for the virtual stimuli, with larger variances at increasing stimulus distances. The described algorithms are implemented in two dynamic linked libraries (Gaze3D.dll and Fixation3D.dll), and we provide a graphical user interface (Gaze3DFixGUI.exe) that is designed for importing 2-D binocular eyetracking data and calculating both 3D gaze points and 3D fixations using the libraries. The Gaze3DFix toolkit, including both libraries and the graphical user interface, is available as open-source software at https://github.com/applied-cognition-research/Gaze3DFix .

  20. Gender and facial dominance in gaze cuing: Emotional context matters in the eyes that we follow

    NARCIS (Netherlands)

    Ohlsen, G.; van Zoest, W.; van Vugt, M.

    2013-01-01

    Gaze following is a socio-cognitive process that provides adaptive information about potential threats and opportunities in the individual's environment. The aim of the present study was to investigate the potential interaction between emotional context and facial dominance in gaze following. We

  1. On uniform resampling and gaze analysis of bidirectional texture functions

    Czech Academy of Sciences Publication Activity Database

    Filip, Jiří; Chantler, M.J.; Haindl, Michal

    2009-01-01

    Roč. 6, č. 3 (2009), s. 1-15 ISSN 1544-3558 R&D Projects: GA MŠk 1M0572; GA ČR GA102/08/0593 Grant - others:EC Marie Curie(BE) 41358 Institutional research plan: CEZ:AV0Z10750506 Keywords : BTF * texture * eye tracking Subject RIV: BD - Theory of Information Impact factor: 1.447, year: 2009 http://library.utia.cas.cz/separaty/2009/RO/haindl-on uniform resampling and gaze analysis of bidirectional texture functions.pdf

  2. Refracted Gazes: A Woman Photographer during Mandate Lebanon

    Directory of Open Access Journals (Sweden)

    Yasmine Nachabe

    2012-11-01

    This paper explores the relationship between modernity and femininity as manifest through the women’s activity, gaze and attire in Marie al-Khazen as well as other photographs taken in the Middle East region between the 1930s and the 1940s. Al-Khazen and the women represented in the photographs of this period were part of a cosmopolitan sensibility that reveals the Middle East region to be far more international than one might have imagined. Caught between projecting a self-image of the cosmopolitan woman and one of the traditional bedouin, these photographs provide a rich field for tracking the ambiguities of the modern.

  3. Sexualized Branded Entertainment and the Male Consumer Gaze

    Directory of Open Access Journals (Sweden)

    Matthew P. McAllister

    2014-03-01

    Full Text Available This article applies the “male consumer gaze” – integrating work influenced by Erving Goffman and Laura Mulvey – to two branded televised events: the 2011 Victoria’s Secret Fashion Show and the 2012 Hooters International Swimsuit Pageant. Critiqued elements include gendered body positioning, televisual and narrativizing techniques, social and integrated media, and branding strategies that combine to create a flow of consumption-based male gazing. Such trends may intensify with changes in media economics and niche marketing.

  4. Human epithelial cells increase their rigidity with ageing in vitro: direct measurements

    International Nuclear Information System (INIS)

    Berdyyeva, Tamara K; Woodworth, Craig D; Sokolov, Igor

    2005-01-01

    The decrease in elasticity of epithelial tissues with ageing contributes to many human diseases. This change was previously attributed to increased crosslinking of extracellular matrix proteins. Here we show that individual human epithelial cells also become significantly more rigid during ageing in vitro. Using atomic force microscopy (AFM), we found that the Young's modulus of viable cells was consistently increased two- to four-fold in older versus younger cells. Direct visualization of the cytoskeleton using a novel method involving the AFM suggested that increased rigidity of ageing cells was due to a higher density of cytoskeletal fibres. Our results identify a unique mechanism that might contribute to the age-related loss of elasticity in epithelial tissues

  5. Efficient Generation of Human Embryonic Stem Cell-Derived Corneal Endothelial Cells by Directed Differentiation.

    Directory of Open Access Journals (Sweden)

    Kathryn L McCabe

    Full Text Available To generate human embryonic stem cell derived corneal endothelial cells (hESC-CECs for transplantation in patients with corneal endothelial dystrophies.Feeder-free hESC-CECs were generated by a directed differentiation protocol. hESC-CECs were characterized by morphology, expression of corneal endothelial markers, and microarray analysis of gene expression.hESC-CECs were nearly identical morphologically to primary human corneal endothelial cells, expressed Zona Occludens 1 (ZO-1 and Na+/K+ATPaseα1 (ATPA1 on the apical surface in monolayer culture, and produced the key proteins of Descemet's membrane, Collagen VIIIα1 and VIIIα2 (COL8A1 and 8A2. Quantitative PCR analysis revealed expression of all corneal endothelial pump transcripts. hESC-CECs were 96% similar to primary human adult CECs by microarray analysis.hESC-CECs are morphologically similar, express corneal endothelial cell markers and express a nearly identical complement of genes compared to human adult corneal endothelial cells. hESC-CECs may be a suitable alternative to donor-derived corneal endothelium.

  6. Anodal transcranial direct current stimulation reduces psychophysically measured surround suppression in the human visual cortex.

    Directory of Open Access Journals (Sweden)

    Daniel P Spiegel

    Full Text Available Transcranial direct current stimulation (tDCS is a safe, non-invasive technique for transiently modulating the balance of excitation and inhibition within the human brain. It has been reported that anodal tDCS can reduce both GABA mediated inhibition and GABA concentration within the human motor cortex. As GABA mediated inhibition is thought to be a key modulator of plasticity within the adult brain, these findings have broad implications for the future use of tDCS. It is important, therefore, to establish whether tDCS can exert similar effects within non-motor brain areas. The aim of this study was to assess whether anodal tDCS could reduce inhibitory interactions within the human visual cortex. Psychophysical measures of surround suppression were used as an index of inhibition within V1. Overlay suppression, which is thought to originate within the lateral geniculate nucleus (LGN, was also measured as a control. Anodal stimulation of the occipital poles significantly reduced psychophysical surround suppression, but had no effect on overlay suppression. This effect was specific to anodal stimulation as cathodal stimulation had no effect on either measure. These psychophysical results provide the first evidence for tDCS-induced reductions of intracortical inhibition within the human visual cortex.

  7. Direct radiocarbon dating and DNA analysis of the Darra-i-Kur (Afghanistan) human temporal bone.

    Science.gov (United States)

    Douka, Katerina; Slon, Viviane; Stringer, Chris; Potts, Richard; Hübner, Alexander; Meyer, Matthias; Spoor, Fred; Pääbo, Svante; Higham, Tom

    2017-06-01

    The temporal bone discovered in the 1960s from the Darra-i-Kur cave in Afghanistan is often cited as one of the very few Pleistocene human fossils from Central Asia. Here we report the first direct radiocarbon date for the specimen and the genetic analyses of DNA extracted and sequenced from two areas of the bone. The new radiocarbon determination places the find to ∼4500 cal BP (∼2500 BCE) contradicting an assumed Palaeolithic age of ∼30,000 years, as originally suggested. The DNA retrieved from the specimen originates from a male individual who carried mitochondrial DNA of the modern human type. The petrous part yielded more endogenous ancient DNA molecules than the squamous part of the same bone. Molecular dating of the Darra-i-Kur mitochondrial DNA sequence corroborates the radiocarbon date and suggests that the specimen is younger than previously thought. Taken together, the results consolidate the fact that the human bone is not associated with the Pleistocene-age deposits of Darra-i-Kur; instead it is intrusive, possibly re-deposited from upper levels dating to much later periods (Neolithic). Despite its Holocene age, the Darra-i-Kur specimen is, so far, the first and only ancient human from Afghanistan whose DNA has been sequenced. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. A Generalized Radiation Model for Human Mobility: Spatial Scale, Searching Direction and Trip Constraint.

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    Chaogui Kang

    Full Text Available We generalized the recently introduced "radiation model", as an analog to the generalization of the classic "gravity model", to consolidate its nature of universality for modeling diverse mobility systems. By imposing the appropriate scaling exponent λ, normalization factor κ and system constraints including searching direction and trip OD constraint, the generalized radiation model accurately captures real human movements in various scenarios and spatial scales, including two different countries and four different cities. Our analytical results also indicated that the generalized radiation model outperformed alternative mobility models in various empirical analyses.

  9. Quantitative assay for the measurement of immune responses directed against the human placenta

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M; Sutcliffe, R G [Glasgow Univ. (UK)

    1982-02-12

    A quantitative in vitro immune assay based on the classical chromium release assay has been developed to detect immune responses directed against alien antigens expressed by the developing foetus and present on the maternal-facing surface of the human placenta. A plasma membrane fraction from the surface of the placenta was prepared and the vesicles thus formed were radiolabelled with /sup 51/Cr. The /sup 51/Cr-labelled vesicles, by various criteria, were found to be suitable for use as targets in a release assay. Further, by means of experimentally immunised animals, the target membranes were shown to be capable of detecting both cellular and humoral anti-placental activity.

  10. Looking at Eye Gaze Processing and Its Neural Correlates in Infancy--Implications for Social Development and Autism Spectrum Disorder

    Science.gov (United States)

    Hoehl, Stefanie; Reid, Vincent M.; Parise, Eugenio; Handl, Andrea; Palumbo, Letizia; Striano, Tricia

    2009-01-01

    The importance of eye gaze as a means of communication is indisputable. However, there is debate about whether there is a dedicated neural module, which functions as an eye gaze detector and when infants are able to use eye gaze cues in a referential way. The application of neuroscience methodologies to developmental psychology has provided new…

  11. Fundamental and clinical study of direct immunoradiometric assay in human renin concentration

    International Nuclear Information System (INIS)

    Kurimoto, Fumihiko; Horiuchi, Junko; Sakurai, Hyoichiro; Suzuki, Hiromichi; Takita, Takashi; Saruta, Takao.

    1988-01-01

    'Renin RIA Pasteur' kit for directly measuring renin concentration in human plasma (PRC) was fundamentally and clinically evaluated. A standard curve for PRC was linear in the range of 10 - 640 pg/ml. Reproducibility, recovery, and stability were satisfactory. There was a significantly positive correlation between direct PRC and conventional plasma renin activity (PRA) and indirect PRC. PRC was directly measured in 119 healthy volunteers and 15 patients with primary aldosteronism (4), Cushing's syndrome (6), or non-functioning tumor (5). The basal PRC was 32.4 +- 18.8 pg/ml for men and 37.9 +- 22.6 pg/ml for women. PRC for primary aldosteronism was below detectable levels, and remained unchanged even after the administratin of ACTH. In the case of Cushing's syndrome, mean PRC and PRA were 19 pg/ml and 1.2 ng/ml/hr, and did not respond to ACTH. Although the administration of ATCH was significantly associated with a decreased PRC, there was only tendency toward the decreased PRA in the case of non-functioning tumors. The results indicate the usefulness of the present kit in terms of its ability to directly measure PRC without any complicated procedures. (Namekawa, K.)

  12. To ban or not to ban: direct-to-consumer advertising and human rights analysis

    Directory of Open Access Journals (Sweden)

    Alex Wellington

    2010-12-01

    Full Text Available The issues surrounding Direct-To-Consumer Advertising of pharmaceuticals are ripe for scrutiny through the lens of Human Rights analysis. Among the human rights most decisively engaged by DTCA is the right to autonomy in health-related decision making, which in turn incorporates right of access to health-related information. The latter incorporates, in part, right of access to reliable and beneficial information through the avenues of commercial speech among others. Another crucial human right is the right not to be harmed by unsafe consumer products through corporate malfeasance or negligence. The most commonly invoked policy options in the context of DTCA are either an outright ban or strengthening regulatory oversight in combination with voluntary guidelines. Banning Direct-To-Consumer Advertising risks being both over inclusive and under inclusive as a policy option. A wholesale ban risks being over inclusive in that it could deprive consumers of information about medications with a positive benefit-risk profile, ones that could enhance their quality of health and well being. Thus it risks being overly paternalistic. Banning DTCA, by itself, is under inclusive in that it is insufficient to address the ways that unadvertised drugs can pose significant risks to consumers. Other policy measures would be most optimal to deal with the very serious deficits in the processes by which prescription drugs undergo clinical trials, and garner regulatory approval prior to their promotion in the marketplace. A more finely tuned approach to regulatory oversight is endorsed, one involving a proactive and precautionary approach reliant upon prior approval. Such an approach could help to address the very serious concerns about potential infringements of the human right not to be harmed by unsafe consumer products through corporate malfeasance or negligence.

  13. Eye-gaze independent EEG-based brain-computer interfaces for communication

    Science.gov (United States)

    Riccio, A.; Mattia, D.; Simione, L.; Olivetti, M.; Cincotti, F.

    2012-08-01

    The present review systematically examines the literature reporting gaze independent interaction modalities in non-invasive brain-computer interfaces (BCIs) for communication. BCIs measure signals related to specific brain activity and translate them into device control signals. This technology can be used to provide users with severe motor disability (e.g. late stage amyotrophic lateral sclerosis (ALS); acquired brain injury) with an assistive device that does not rely on muscular contraction. Most of the studies on BCIs explored mental tasks and paradigms using visual modality. Considering that in ALS patients the oculomotor control can deteriorate and also other potential users could have impaired visual function, tactile and auditory modalities have been investigated over the past years to seek alternative BCI systems which are independent from vision. In addition, various attentional mechanisms, such as covert attention and feature-directed attention, have been investigated to develop gaze independent visual-based BCI paradigms. Three areas of research were considered in the present review: (i) auditory BCIs, (ii) tactile BCIs and (iii) independent visual BCIs. Out of a total of 130 search results, 34 articles were selected on the basis of pre-defined exclusion criteria. Thirteen articles dealt with independent visual BCIs, 15 reported on auditory BCIs and the last six on tactile BCIs, respectively. From the review of the available literature, it can be concluded that a crucial point is represented by the trade-off between BCI systems/paradigms with high accuracy and speed, but highly demanding in terms of attention and memory load, and systems requiring lower cognitive effort but with a limited amount of communicable information. These issues should be considered as priorities to be explored in future studies to meet users’ requirements in a real-life scenario.

  14. A testimony to Muzil: Hervé Guibert, Foucault, and the medical gaze.

    Science.gov (United States)

    Rendell, Joanne

    2004-01-01

    Testimony to Muzil: Hervé Guibert, Michel Foucault, and the "Medical Gaze" examines the fictional/autobiographical AIDS writings of the French writer Hervé Guibert. Locating Guibert's writings alongside the work of his friend Michel Foucault, the article explores how they echo Foucault's evolving notions of the "medical gaze." The article also explores how Guilbert's narrators and Guibert himself (as writer) resist and challenge the medical gaze; a gaze which particularly in the era of AIDS has subjected, objectified, and even sometimes punished the body of the gay man. It is argued that these resistances to the gaze offer a literary extension to Foucault's later work on power and resistance strategies.

  15. Systems Analysis of Human Visuo-Myoelectric Control Facilitated by Anodal Transcranial Direct Current Stimulation in Healthy Humans

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    Vinh Kha

    2018-04-01

    Full Text Available Induction of neuroplasticity by transcranial direct current stimulation (tDCS applied to the primary motor cortex facilitates motor learning of the upper extremities in healthy humans. The impact of tDCS on lower limb functions has not been studied extensively so far. In this study, we applied a system identification approach to investigate the impact of anodal transcranial direct current stimulation of the leg area of the motor cortex via the human visuo-myoelectric controller. The visuo-myoelectric reaching task (VMT involves ballistic muscle contraction after a visual cue. We applied a black box approach using a linear ARX (Auto-regressive with eXogenous input model for a visuomotor myoelectric reaching task. We found that a 20th order finite impulse response (FIR model captured the TARGET (single input—CURSOR (single output dynamics during a VMT. The 20th order FIR model was investigated based on gain/phase margin analysis, which showed a significant (p < 0.01 effect of anodal tDCS on the gain margin of the VMT system. Also, response latency and the corticomuscular coherence (CMC time delay were affected (p < 0.05 by anodal tDCS when compared to sham tDCS. Furthermore, gray box simulation results from a Simplified Spinal-Like Controller (SSLC model demonstrated that the input-output function for motor evoked potentials (MEP played an essential role in increasing muscle activation levels and response time improvement post-tDCS when compared to pre-tDCS baseline performance. This computational approach can be used to simulate the behavior of the neuromuscular controller during VMT to elucidate the effects of adjuvant treatment with tDCS.

  16. Direct Differentiation of Human Pluripotent Stem Cells into Haploid Spermatogenic Cells

    Directory of Open Access Journals (Sweden)

    Charles A. Easley, IV

    2012-09-01

    Full Text Available Human embryonic stem cells (hESCs and induced pluripotent stem cells (hiPSCs have been shown to differentiate into primordial germ cells (PGCs but not into spermatogonia, haploid spermatocytes, or spermatids. Here, we show that hESCs and hiPSCs differentiate directly into advanced male germ cell lineages, including postmeiotic, spermatid-like cells, in vitro without genetic manipulation. Furthermore, our procedure mirrors spermatogenesis in vivo by differentiating PSCs into UTF1-, PLZF-, and CDH1-positive spermatogonia-like cells; HIWI- and HILI-positive spermatocyte-like cells; and haploid cells expressing acrosin, transition protein 1, and protamine 1 (proteins that are uniquely found in spermatids and/or sperm. These spermatids show uniparental genomic imprints similar to those of human sperm on two loci: H19 and IGF2. These results demonstrate that male PSCs have the ability to differentiate directly into advanced germ cell lineages and may represent a novel strategy for studying spermatogenesis in vitro.

  17. p21-Activated kinase (PAK regulates cytoskeletal reorganization and directional migration in human neutrophils.

    Directory of Open Access Journals (Sweden)

    Asako Itakura

    Full Text Available Neutrophils serve as a first line of defense in innate immunity owing in part to their ability to rapidly migrate towards chemotactic factors derived from invading pathogens. As a migratory function, neutrophil chemotaxis is regulated by the Rho family of small GTPases. However, the mechanisms by which Rho GTPases orchestrate cytoskeletal dynamics in migrating neutrophils remain ill-defined. In this study, we characterized the role of p21-activated kinase (PAK downstream of Rho GTPases in cytoskeletal remodeling and chemotactic processes of human neutrophils. We found that PAK activation occurred upon stimulation of neutrophils with f-Met-Leu-Phe (fMLP, and PAK accumulated at the actin-rich leading edge of stimulated neutrophils, suggesting a role for PAK in Rac-dependent actin remodeling. Treatment with the pharmacological PAK inhibitor, PF3758309, abrogated the integrity of RhoA-mediated actomyosin contractility and surface adhesion. Moreover, inhibition of PAK activity impaired neutrophil morphological polarization and directional migration under a gradient of fMLP, and was associated with dysregulated Ca(2+ signaling. These results suggest that PAK serves as an important effector of Rho-family GTPases in neutrophil cytoskeletal reorganization, and plays a key role in driving efficient directional migration of human neutrophils.

  18. Direct effects of fermented cow's milk product with Lactobacillus paracasei CBA L74 on human enterocytes.

    Science.gov (United States)

    Paparo, L; Aitoro, R; Nocerino, R; Fierro, C; Bruno, C; Canani, R Berni

    2018-01-29

    Cow's milk fermented with Lactobacillus paracasei CBA L74 (FM-CBAL74) exerts a preventive effect against infectious diseases in children. We evaluated if this effect is at least in part related to a direct modulation of non-immune and immune defence mechanisms in human enterocytes. Human enterocytes (Caco-2) were stimulated for 48 h with FM-CBAL74 at different concentrations. Cell growth was assessed by colorimetric assay; cell differentiation (assessed by lactase expression), tight junction proteins (zonula occludens1 and occludin), mucin 2, and toll-like receptor (TRL) pathways were analysed by real-time PCR; innate immunity peptide synthesis, beta-defensin-2 (HBD-2) and cathelicidin (LL-37) were evaluated by ELISA. Mucus layer thickness was analysed by histochemistry. FMCBA L74 stimulated cell growth and differentiation, tight junction proteins and mucin 2 expression, and mucus layer thickness in a dose-dependent fashion. A significant stimulation of HBD-2 and LL-37 synthesis, associated with a modulation of TLR pathway, was also observed. FM-CBAL74 regulates non-immune and immune defence mechanisms through a direct interaction with the enterocytes. These effects could be involved in the preventive action against infectious diseases demonstrated by this fermented product in children.

  19. Development and optimization of a direct plaque assay for human and avian metapneumoviruses

    Science.gov (United States)

    Zhang, Yu; Wei, Yongwei; Li, Junan; Li, Jianrong

    2012-01-01

    The genus Metapneumovirus within the subfamily Pneumovirinae and family Paramyxoviridae includes only two viruses, human metapneumovirus (hMPV) and avian metapneumovirus (aMPV), which cause respiratory disease in humans and birds, respectively. These two viruses grow poorly in cell culture and other quantitation methods, such as indirect immuno-staining and immuno-fluorescent assays, are expensive, time consuming, and do not allow for plaque purification of the virus. In order to enhance research efforts for studying these two viruses, a direct plaque assay for both hMPV and aMPV has been developed. By optimizing the chemical components of the agarose overlay, it was found that both hMPV with a trypsin-independent F cleavage site and aMPV formed clear and countable plaques in a number of mammalian cell lines (such as Vero-E6 and LLC-MK2 cells) after 5 days of incubation. The plaque forming assay has similar sensitivity and reliability as the currently used immunological methods for viral quantitation. The plaque assay is also a more simple, rapid, and economical method compared to immunological assays, and in addition allows for plaque purification of the viruses. The direct plaque assay will be a valuable method for the quantitation and evaluation of the biological properties of some metapneumoviruses. PMID:22684013

  20. Vicarious Social Touch Biases Gazing at Faces and Facial Emotions.

    Science.gov (United States)

    Schirmer, Annett; Ng, Tabitha; Ebstein, Richard P

    2018-02-01

    Research has suggested that interpersonal touch promotes social processing and other-concern, and that women may respond to it more sensitively than men. In this study, we asked whether this phenomenon would extend to third-party observers who experience touch vicariously. In an eye-tracking experiment, participants (N = 64, 32 men and 32 women) viewed prime and target images with the intention of remembering them. Primes comprised line drawings of dyadic interactions with and without touch. Targets comprised two faces shown side-by-side, with one being neutral and the other being happy or sad. Analysis of prime fixations revealed that faces in touch interactions attracted longer gazing than faces in no-touch interactions. In addition, touch enhanced gazing at the area of touch in women but not men. Analysis of target fixations revealed that touch priming increased looking at both faces immediately after target onset, and subsequently, at the emotional face in the pair. Sex differences in target processing were nonsignificant. Together, the present results imply that vicarious touch biases visual attention to faces and promotes emotion sensitivity. In addition, they suggest that, compared with men, women are more aware of tactile exchanges in their environment. As such, vicarious touch appears to share important qualities with actual physical touch. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  1. Pharmacological modulation of cortical excitability shifts induced by transcranial direct current stimulation in humans.

    Science.gov (United States)

    Nitsche, M A; Fricke, K; Henschke, U; Schlitterlau, A; Liebetanz, D; Lang, N; Henning, S; Tergau, F; Paulus, W

    2003-11-15

    Transcranial direct current stimulation (tDCS) of the human motor cortex results in polarity-specific shifts of cortical excitability during and after stimulation. Anodal tDCS enhances and cathodal stimulation reduces excitability. Animal experiments have demonstrated that the effect of anodal tDCS is caused by neuronal depolarisation, while cathodal tDCS hyperpolarises cortical neurones. However, not much is known about the ion channels and receptors involved in these effects. Thus, the impact of the sodium channel blocker carbamazepine, the calcium channel blocker flunarizine and the NMDA receptor antagonist dextromethorphane on tDCS-elicited motor cortical excitability changes of healthy human subjects were tested. tDCS-protocols inducing excitability alterations (1) only during tDCS and (2) eliciting long-lasting after-effects were applied after drug administration. Carbamazepine selectively eliminated the excitability enhancement induced by anodal stimulation during and after tDCS. Flunarizine resulted in similar changes. Antagonising NMDA receptors did not alter current-generated excitability changes during a short stimulation, which elicits no after-effects, but prevented the induction of long-lasting after-effects independent of their direction. These results suggest that, like in other animals, cortical excitability shifts induced during tDCS in humans also depend on membrane polarisation, thus modulating the conductance of sodium and calcium channels. Moreover, they suggest that the after-effects may be NMDA receptor dependent. Since NMDA receptors are involved in neuroplastic changes, the results suggest a possible application of tDCS in the modulation or induction of these processes in a clinical setting. The selective elimination of tDCS-driven excitability enhancements by carbamazepine proposes a role for this drug in focussing the effects of cathodal tDCS, which may have important future clinical applications.

  2. Female-directed violence as a form of sexual coercion in humans (Homo sapiens).

    Science.gov (United States)

    Barbaro, Nicole; Shackelford, Todd K

    2016-11-01

    Male-perpetrated female-directed violence (FDV) may be associated with greater sexual access to a female. Accordingly, FDV is expected to be associated with greater copulation frequency. Research on nonhuman primates affirms this hypothesis, but no previous research has investigated this relationship in humans (Homo sapiens). The current research tests the hypothesis that FDV is associated with in-pair copulation frequency and, thus, may function as a form of sexual coercion. It was predicted that men who perpetrate FDV will secure more in-pair copulations than men who do not perpetrate violence (Prediction 1a), and that average monthly rates of FDV would positively correlate with in-pair copulation frequency (Prediction 1b). Male participants (n = 355) completed a survey, reporting limited demographic information (e.g., age, relationship length), in-pair copulation frequency, and history of physical violence perpetration. As predicted, violent men secured more in-pair copulations, on average, than nonviolent men, and monthly rates of violence positively correlated with in-pair copulation frequency. In humans, as in nonhuman primates, FDV by males may facilitate greater sexual access to a female. We discuss the implications of the current research for an evolutionary perspective on partner violence, and draw on research on nonhuman primates to highlight profitable avenues of research on FDV in humans. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  3. Detection of antibodies in human serum using trimellityl-erythrocytes: direct and indirect haemagglutination and haemolysis.

    Science.gov (United States)

    Turner, E S; Pruzansky, J J; Patterson, R; Zeiss, C R; Roberts, M

    1980-02-01

    Utilizing trimellityl-erythrocytes (TM-E), antibodies were detected in sera of seven workers with trimellitic anhydride (TMA) induced airway syndromes by direct haemagglutination, indirect haemagglutination with anti-human IgG, IgA or IgM or by haemolysis. Detectable levels of antibody were obtained with all three methods. The most sensitive technique was indirect haemagglutination using anti-IgG. When added as an inhibitor, TM-human serum albumin produced a 10- to 800-fold reduction in titres. TM-ovalbumin of similar epitope density was less inhibitory and sodium trimellitate the least inhibitory on a molar basis. All of the assays using haptenized human red cells were also capable of detecting anti-TM antibodies in Rhesus monkeys whose airways had been exposed to TMA. These assays are useful for detecting anti-TM antibodies and may also be adapted to demonstrate antibodies induced against other inhaled haptens in sera of environmentally exposed individuals or in animal models of such exposure.

  4. Decoding conjunctions of direction-of-motion and binocular disparity from human visual cortex.

    Science.gov (United States)

    Seymour, Kiley J; Clifford, Colin W G

    2012-05-01

    Motion and binocular disparity are two features in our environment that share a common correspondence problem. Decades of psychophysical research dedicated to understanding stereopsis suggest that these features interact early in human visual processing to disambiguate depth. Single-unit recordings in the monkey also provide evidence for the joint encoding of motion and disparity across much of the dorsal visual stream. Here, we used functional MRI and multivariate pattern analysis to examine where in the human brain conjunctions of motion and disparity are encoded. Subjects sequentially viewed two stimuli that could be distinguished only by their conjunctions of motion and disparity. Specifically, each stimulus contained the same feature information (leftward and rightward motion and crossed and uncrossed disparity) but differed exclusively in the way these features were paired. Our results revealed that a linear classifier could accurately decode which stimulus a subject was viewing based on voxel activation patterns throughout the dorsal visual areas and as early as V2. This decoding success was conditional on some voxels being individually sensitive to the unique conjunctions comprising each stimulus, thus a classifier could not rely on independent information about motion and binocular disparity to distinguish these conjunctions. This study expands on evidence that disparity and motion interact at many levels of human visual processing, particularly within the dorsal stream. It also lends support to the idea that stereopsis is subserved by early mechanisms also tuned to direction of motion.

  5. Pupil size directly modulates the feedforward response in human primary visual cortex independently of attention.

    Science.gov (United States)

    Bombeke, Klaas; Duthoo, Wout; Mueller, Sven C; Hopf, Jens-Max; Boehler, C Nico

    2016-02-15

    Controversy revolves around the question of whether psychological factors like attention and emotion can influence the initial feedforward response in primary visual cortex (V1). Although traditionally, the electrophysiological correlate of this response in humans (the C1 component) has been found to be unaltered by psychological influences, a number of recent studies have described attentional and emotional modulations. Yet, research into psychological effects on the feedforward V1 response has neglected possible direct contributions of concomitant pupil-size modulations, which are known to also occur under various conditions of attentional load and emotional state. Here we tested the hypothesis that such pupil-size differences themselves directly affect the feedforward V1 response. We report data from two complementary experiments, in which we used procedures that modulate pupil size without differences in attentional load or emotion while simultaneously recording pupil-size and EEG data. Our results confirm that pupil size indeed directly influences the feedforward V1 response, showing an inverse relationship between pupil size and early V1 activity. While it is unclear in how far this effect represents a functionally-relevant adaptation, it identifies pupil-size differences as an important modulating factor of the feedforward response of V1 and could hence represent a confounding variable in research investigating the neural influence of psychological factors on early visual processing. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. EEG Negativity in Fixations Used for Gaze-Based Control: Toward Converting Intentions into Actions with an Eye-Brain-Computer Interface

    Science.gov (United States)

    Shishkin, Sergei L.; Nuzhdin, Yuri O.; Svirin, Evgeny P.; Trofimov, Alexander G.; Fedorova, Anastasia A.; Kozyrskiy, Bogdan L.; Velichkovsky, Boris M.

    2016-01-01

    We usually look at an object when we are going to manipulate it. Thus, eye tracking can be used to communicate intended actions. An effective human-machine interface, however, should be able to differentiate intentional and spontaneous eye movements. We report an electroencephalogram (EEG) marker that differentiates gaze fixations used for control from spontaneous fixations involved in visual exploration. Eight healthy participants played a game with their eye movements only. Their gaze-synchronized EEG data (fixation-related potentials, FRPs) were collected during game's control-on and control-off conditions. A slow negative wave with a maximum in the parietooccipital region was present in each participant's averaged FRPs in the control-on conditions and was absent or had much lower amplitude in the control-off condition. This wave was similar but not identical to stimulus-preceding negativity, a slow negative wave that can be observed during feedback expectation. Classification of intentional vs. spontaneous fixations was based on amplitude features from 13 EEG channels using 300 ms length segments free from electrooculogram contamination (200–500 ms relative to the fixation onset). For the first fixations in the fixation triplets required to make moves in the game, classified against control-off data, a committee of greedy classifiers provided 0.90 ± 0.07 specificity and 0.38 ± 0.14 sensitivity. Similar (slightly lower) results were obtained for the shrinkage Linear Discriminate Analysis (LDA) classifier. The second and third fixations in the triplets were classified at lower rate. We expect that, with improved feature sets and classifiers, a hybrid dwell-based Eye-Brain-Computer Interface (EBCI) can be built using the FRP difference between the intended and spontaneous fixations. If this direction of BCI development will be successful, such a multimodal interface may improve the fluency of interaction and can possibly become the basis for a new input device

  7. EEG Negativity in Fixations Used for Gaze-Based Control: Toward Converting Intentions into Actions with an Eye-Brain-Computer Interface

    Directory of Open Access Journals (Sweden)

    Sergei L. Shishkin

    2016-11-01

    Full Text Available We usually look at an object when we are going to manipulate it. Thus, eye tracking can be used to communicate intended actions. An effective human-machine interface, however, should be able to differentiate intentional and spontaneous eye movements. We report an electroencephalogram (EEG marker that differentiates gaze fixations used for control from spontaneous fixations involved in visual exploration. Eight healthy participants played a game with their eye movements only. Their gaze-synchronized EEG data (fixation-related potentials, FRPs were collected during game’s control-on and control-off conditions. A slow negative wave with a maximum in the parietooccipital region was present in each participant’s averaged FRPs in the control-on conditions and was absent or had much lower amplitude in the control-off condition. This wave was similar but not identical to stimulus-preceding negativity, a slow negative wave that can be observed during feedback expectation. Classification of intentional vs. spontaneous fixations was based on amplitude features from 13 EEG channels using 300 ms length segments free from electrooculogram contamination (200..500 ms relative to the fixation onset. For the first fixations in the fixation triplets required to make moves in the game, classified against control-off data, a committee of greedy classifiers provided 0.90 ± 0.07 specificity and 0.38 ± 0.14 sensitivity. Similar (slightly lower results were obtained for the shrinkage LDA classifier. The second and third fixations in the triplets were classified at lower rate. We expect that, with improved feature sets and classifiers, a hybrid dwell-based Eye-Brain-Computer Interface (EBCI can be built using the FRP difference between the intended and spontaneous fixations. If this direction of BCI development will be successful, such a multimodal interface may improve the fluency of interaction and can possibly become the basis for a new input device for

  8. Perceiving where another person is looking: The integration of head and body information in estimating another person’s gaze.

    Directory of Open Access Journals (Sweden)

    Pieter eMoors

    2015-06-01

    Full Text Available The process through which an observer allocates his/her attention based on the attention of another person is known as joint attention. To be able to do this, the observer effectively has to compute where the other person is looking. It has been shown that observers integrate information from the head and the eyes to determine the gaze of another person. Most studies have documented that observers show a bias called the overshoot effect when eyes and head are misaligned. The present study addresses whether body information is also used as a cue to compute perceived gaze direction. In Experiment 1, we observed a similar overshoot effect in both behavioral and saccadic responses when manipulating body orientation. In Experiment 2, we explored whether the overshoot effect was due to observers assuming that the eyes are oriented further than the head when head and body orientation are misaligned. We removed horizontal eye information by presenting the stimulus from a side view. Head orientation was now manipulated in a vertical direction and the overshoot effect was replicated. In summary, this study shows that body orientation is indeed used as a cue to determine where another person is looking.

  9. The Needs of Male Visuality: The Rhetoric of Male Gaze in Snuff and Hard-Core Culture between Cinema and Literature

    Directory of Open Access Journals (Sweden)

    Mirko Lino

    2014-06-01

    -  Social and cultural: the need of having to re-establish male dominance against the destructuring action of feminism. The field of analysis of cinematographic and literary outputs is focused on two titles: Snuff (1976 a movie produced by A. Shackleton, and the novel Snuff (2008 by Chuck Palahniuk. The movie is useful for the description of a snuff aesthetic and the rhetoric of male gaze; the novel instead is useful for the identification of relevant features about gender questions applied to extreme hard core pornography. At the end, it will be demonstrated the political attempt to reverse the hegemonic rhetoric of male gaze acting directly on the aesthetic of snuff movie ritual.

  10. Type 2 diabetes risk alleles demonstrate extreme directional differentiation among human populations, compared to other diseases.

    Directory of Open Access Journals (Sweden)

    Rong Chen

    Full Text Available Many disease-susceptible SNPs exhibit significant disparity in ancestral and derived allele frequencies across worldwide populations. While previous studies have examined population differentiation of alleles at specific SNPs, global ethnic patterns of ensembles of disease risk alleles across human diseases are unexamined. To examine these patterns, we manually curated ethnic disease association data from 5,065 papers on human genetic studies representing 1,495 diseases, recording the precise risk alleles and their measured population frequencies and estimated effect sizes. We systematically compared the population frequencies of cross-ethnic risk alleles for each disease across 1,397 individuals from 11 HapMap populations, 1,064 individuals from 53 HGDP populations, and 49 individuals with whole-genome sequences from 10 populations. Type 2 diabetes (T2D demonstrated extreme directional differentiation of risk allele frequencies across human populations, compared with null distributions of European-frequency matched control genomic alleles and risk alleles for other diseases. Most T2D risk alleles share a consistent pattern of decreasing frequencies along human migration into East Asia. Furthermore, we show that these patterns contribute to disparities in predicted genetic risk across 1,397 HapMap individuals, T2D genetic risk being consistently higher for individuals in the African populations and lower in the Asian populations, irrespective of the ethnicity considered in the initial discovery of risk alleles. We observed a similar pattern in the distribution of T2D Genetic Risk Scores, which are associated with an increased risk of developing diabetes in the Diabetes Prevention Program cohort, for the same individuals. This disparity may be attributable to the promotion of energy storage and usage appropriate to environments and inconsistent energy intake. Our results indicate that the differential frequencies of T2D risk alleles may

  11. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study.

    Science.gov (United States)

    Barsingerhorn, A D; Boonstra, F N; Goossens, H H L M

    2017-02-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different stereo eye-tracking methods. We found that pupil size, gaze direction and head position all influence the reconstruction of gaze. Resulting errors range between ± 1.0 degrees at best. This shows that stereo eye-tracking may be an option if reliable calibration is not possible, but the applied eye-model should account for the actual optics of the cornea.

  12. P2-23: Deficits on Preference but Not Attention in Patients with Depression: Evidence from Gaze Cue

    Directory of Open Access Journals (Sweden)

    Jingling Li

    2012-10-01

    Full Text Available Gaze is an important social cue and can easily capture attention. Our preference judgment is biased by others' gaze; that is, we prefer objects gazed by happy or neutral faces and dislike objects gazed by disgust faces. Since patients with depression have a negative bias in emotional perception, we hypothesized that they may have different preference judgment on the gazed objects than healthy controls. Twenty-one patients with major depressive disorder and 21 healthy age-matched controls completed an object categorization task and then rated their preference on those objects. In the categorization task, a schematic face either gazed toward or away from the to-be-categorized object. The results showed that both groups categorized faster for gazed objects than non-gazed objects, suggesting that patients did not have deficits on their attention to gaze cues. Nevertheless, healthy controls preferred gazed objects more than non-gazed objects, while patients did not have significant preference. Our result indicated that patients with depression have deficits on their social cognition rather than basic attentional mechanism.

  13. Gaze-Contingent Music Reward Therapy for Social Anxiety Disorder: A Randomized Controlled Trial.

    Science.gov (United States)

    Lazarov, Amit; Pine, Daniel S; Bar-Haim, Yair

    2017-07-01

    Patients with social anxiety disorder exhibit increased attentional dwelling on social threats, providing a viable target for therapeutics. This randomized controlled trial examined the efficacy of a novel gaze-contingent music reward therapy for social anxiety disorder designed to reduce attention dwelling on threats. Forty patients with social anxiety disorder were randomly assigned to eight sessions of either gaze-contingent music reward therapy, designed to divert patients' gaze toward neutral stimuli rather than threat stimuli, or to a control condition. Clinician and self-report measures of social anxiety were acquired pretreatment, posttreatment, and at 3-month follow-up. Dwell time on socially threatening faces was assessed during the training sessions and at pre- and posttreatment. Gaze-contingent music reward therapy yielded greater reductions of symptoms of social anxiety disorder than the control condition on both clinician-rated and self-reported measures. Therapeutic effects were maintained at follow-up. Gaze-contingent music reward therapy, but not the control condition, also reduced dwell time on threat, which partially mediated clinical effects. Finally, gaze-contingent music reward therapy, but not the control condition, also altered dwell time on socially threatening faces not used in training, reflecting near-transfer training generalization. This is the first randomized controlled trial to examine a gaze-contingent intervention in social anxiety disorder. The results demonstrate target engagement and clinical effects. This study sets the stage for larger randomized controlled trials and testing in other emotional disorders.

  14. Aversive eye gaze during a speech in virtual environment in patients with social anxiety disorder.

    Science.gov (United States)

    Kim, Haena; Shin, Jung Eun; Hong, Yeon-Ju; Shin, Yu-Bin; Shin, Young Seok; Han, Kiwan; Kim, Jae-Jin; Choi, Soo-Hee

    2018-03-01

    One of the main characteristics of social anxiety disorder is excessive fear of social evaluation. In such situations, anxiety can influence gaze behaviour. Thus, the current study adopted virtual reality to examine eye gaze pattern of social anxiety disorder patients while presenting different types of speeches. A total of 79 social anxiety disorder patients and 51 healthy controls presented prepared speeches on general topics and impromptu speeches on self-related topics to a virtual audience while their eye gaze was recorded. Their presentation performance was also evaluated. Overall, social anxiety disorder patients showed less eye gaze towards the audience than healthy controls. Types of speech did not influence social anxiety disorder patients' gaze allocation towards the audience. However, patients with social anxiety disorder showed significant correlations between the amount of eye gaze towards the audience while presenting self-related speeches and social anxiety cognitions. The current study confirms that eye gaze behaviour of social anxiety disorder patients is aversive and that their anxiety symptoms are more dependent on the nature of topic.

  15. Gaze Behavior of Children with ASD toward Pictures of Facial Expressions.

    Science.gov (United States)

    Matsuda, Soichiro; Minagawa, Yasuyo; Yamamoto, Junichi

    2015-01-01

    Atypical gaze behavior in response to a face has been well documented in individuals with autism spectrum disorders (ASDs). Children with ASD appear to differ from typically developing (TD) children in gaze behavior for spoken and dynamic face stimuli but not for nonspeaking, static face stimuli. Furthermore, children with ASD and TD children show a difference in their gaze behavior for certain expressions. However, few studies have examined the relationship between autism severity and gaze behavior toward certain facial expressions. The present study replicated and extended previous studies by examining gaze behavior towards pictures of facial expressions. We presented ASD and TD children with pictures of surprised, happy, neutral, angry, and sad facial expressions. Autism severity was assessed using the Childhood Autism Rating Scale (CARS). The results showed that there was no group difference in gaze behavior when looking at pictures of facial expressions. Conversely, the children with ASD who had more severe autistic symptomatology had a tendency to gaze at angry facial expressions for a shorter duration in comparison to other facial expressions. These findings suggest that autism severity should be considered when examining atypical responses to certain facial expressions.

  16. Gender and facial dominance in gaze cuing: emotional context matters in the eyes that we follow.

    Directory of Open Access Journals (Sweden)

    Garian Ohlsen

    Full Text Available Gaze following is a socio-cognitive process that provides adaptive information about potential threats and opportunities in the individual's environment. The aim of the present study was to investigate the potential interaction between emotional context and facial dominance in gaze following. We used the gaze cue task to induce attention to or away from the location of a target stimulus. In the experiment, the gaze cue either belonged to a (dominant looking male face or a (non-dominant looking female face. Critically, prior to the task, individuals were primed with pictures of threat or no threat to induce either a dangerous or safe environment. Findings revealed that the primed emotional context critically influenced the gaze cuing effect. While a gaze cue of the dominant male face influenced performance in both the threat and no-threat conditions, the gaze cue of the non-dominant female face only influenced performance in the no-threat condition. This research suggests an implicit, context-dependent follower bias, which carries implications for research on visual attention, social cognition, and leadership.

  17. Impedimetric immunosensor for human serum albumin detection on a direct aldehyde-functionalized silicon nitride surface

    Energy Technology Data Exchange (ETDEWEB)

    Caballero, David, E-mail: caballero@unistra.fr [Nanobioengineering group-IBEC, Barcelona Science Park, C/ Baldiri Reixach 10-12, 08028 Barcelona (Spain); University of Barcelona, Department of Electronics, C/ Marti i Franques 1, 08028 Barcelona (Spain); Centro de Investigacion Biomedica en Red en Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 50018 Zaragoza (Spain); Martinez, Elena [Nanobioengineering group-IBEC, Barcelona Science Park, C/ Baldiri Reixach 10-12, 08028 Barcelona (Spain); Centro de Investigacion Biomedica en Red en Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 50018 Zaragoza (Spain); Bausells, Joan [Centre Nacional de Microelectronica (CNM-IMB), CSIC, Campus UAB, 08193 Bellaterra (Spain); Errachid, Abdelhamid, E-mail: abdelhamid.errachid-el-salhi@univ-lyon1.fr [Nanobioengineering group-IBEC, Barcelona Science Park, C/ Baldiri Reixach 10-12, 08028 Barcelona (Spain); Universite Claude Bernard - Lyon 1, LSA - UMR 5180, 43 Bd du 11 novembre 1918, 69622 Villeurbanne Cedex (France); Samitier, Josep [Nanobioengineering group-IBEC, Barcelona Science Park, C/ Baldiri Reixach 10-12, 08028 Barcelona (Spain); University of Barcelona, Department of Electronics, C/ Marti i Franques 1, 08028 Barcelona (Spain); Centro de Investigacion Biomedica en Red en Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 50018 Zaragoza (Spain)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer An impedimetric label-free immunosensor was developed for the specific detection of human serum albumin proteins. Black-Right-Pointing-Pointer Anti-HSA antibodies were covalently immobilized on silicon nitride surfaces using a direct functionalization methodology. Black-Right-Pointing-Pointer Silicon nitride offers multiple advantages compared to other common materials. Black-Right-Pointing-Pointer The proposed sensor has high sensitivity and good selectivity for the detection of HSA proteins. - Abstract: In this work we report the fabrication and characterization of a label-free impedimetric immunosensor based on a silicon nitride (Si{sub 3}N{sub 4}) surface for the specific detection of human serum albumin (HSA) proteins. Silicon nitride provides several advantages compared with other materials commonly used, such as gold, and in particular in solid-state physics for electronic-based biosensors. However, few Si{sub 3}N{sub 4}-based biosensors have been developed; the lack of an efficient and direct protocol for the integration of biological elements with silicon-based substrates is still one of its the main drawbacks. Here, we use a direct functionalization method for the direct covalent binding of monoclonal anti-HSA antibodies on an aldehyde-functionalized Si-p/SiO{sub 2}/Si{sub 3}N{sub 4} structure. This methodology, in contrast with most of the protocols reported in literature, requires less chemical reagents, it is less time-consuming and it does not need any chemical activation. The detection capability of the immunosensor was tested by performing non-faradaic electrochemical impedance spectroscopy (EIS) measurements for the specific detection of HSA proteins. Protein concentrations within the linear range of 10{sup -13}-10{sup -7} M were detected, showing a sensitivity of 0.128 {Omega} {mu}M{sup -1} and a limit of detection of 10{sup -14} M. The specificity of the sensor was also addressed by studying the

  18. Impedimetric immunosensor for human serum albumin detection on a direct aldehyde-functionalized silicon nitride surface

    International Nuclear Information System (INIS)

    Caballero, David; Martinez, Elena; Bausells, Joan; Errachid, Abdelhamid; Samitier, Josep

    2012-01-01

    Highlights: ► An impedimetric label-free immunosensor was developed for the specific detection of human serum albumin proteins. ► Anti-HSA antibodies were covalently immobilized on silicon nitride surfaces using a direct functionalization methodology. ► Silicon nitride offers multiple advantages compared to other common materials. ► The proposed sensor has high sensitivity and good selectivity for the detection of HSA proteins. - Abstract: In this work we report the fabrication and characterization of a label-free impedimetric immunosensor based on a silicon nitride (Si 3 N 4 ) surface for the specific detection of human serum albumin (HSA) proteins. Silicon nitride provides several advantages compared with other materials commonly used, such as gold, and in particular in solid-state physics for electronic-based biosensors. However, few Si 3 N 4 -based biosensors have been developed; the lack of an efficient and direct protocol for the integration of biological elements with silicon-based substrates is still one of its the main drawbacks. Here, we use a direct functionalization method for the direct covalent binding of monoclonal anti-HSA antibodies on an aldehyde-functionalized Si-p/SiO 2 /Si 3 N 4 structure. This methodology, in contrast with most of the protocols reported in literature, requires less chemical reagents, it is less time-consuming and it does not need any chemical activation. The detection capability of the immunosensor was tested by performing non-faradaic electrochemical impedance spectroscopy (EIS) measurements for the specific detection of HSA proteins. Protein concentrations within the linear range of 10 −13 –10 −7 M were detected, showing a sensitivity of 0.128 Ω μM −1 and a limit of detection of 10 −14 M. The specificity of the sensor was also addressed by studying the interferences with a similar protein, bovine serum albumin. The results obtained show that the antibodies were efficiently immobilized and the proteins

  19. Animating Flames: Recovering Fire-Gazing as a Moving-Image Technology

    Directory of Open Access Journals (Sweden)

    Anne Sullivan

    2017-12-01

    Full Text Available In nineteenth-century England, the industrialization of heat and light rendered fire-gazing increasingly obsolete. Fire-gazing is a form of flame-based reverie that typically involves a solitary viewer who perceives animated, moving images dissolving into and out of view in a wood or coal fire. When fire-gazing, the viewer may perceive arbitrary pictures, fantastic landscapes, or more familiar forms, such as the faces of friends and family. This article recovers fire-gazing as an early and more intimate animation technology by examining remediations of fire-gazing in print. After reviewing why an analysis of fire-gazing requires a joint literary and media history approach, I build from Michael Faraday’s mid-nineteenth-century theorization of flame as a moving image to argue that fire-gazing must be included in the history of animation technologies. I then demonstrate the uneasy connections that form between automatism, mechanical reproduction, and creativity in Leigh Hunt’s description of fire-gazing in his 1811 essay ‘A Day by the Fire’. The tension between conscious and unconscious modes of production culminates in a discussion of fireside scenes of (reanimation in Charles Dickens’s 'Our Mutual Friend' (1864–65, including those featuring one of his more famous fire-gazers, Lizzie Hexam. The article concludes with a brief discussion of the 1908 silent film 'Fireside Reminiscences' as an example of the continued remediations of fire-gazing beyond the nineteenth century.

  20. Direct visualization of HIV-enhancing endogenous amyloid fibrils in human semen

    Science.gov (United States)

    Usmani, Shariq M.; Zirafi, Onofrio; Müller, Janis; Sandi-Monroy, Nathallie; Yadav, Jay K.; Meier, Christoph; Weil, Tanja; Roan, Nadia R.; Greene, Warner C.; Walther, Paul; Nilsson, K. Peter R.; Hammarström, Per; Wetzel, Ronald; Pilcher, Christopher D.; Gagsteiger, Friedrich; Fändrich, Marcus; Kirchhoff, Frank; Münch, Jan

    2014-01-01

    Naturally occurring fragments of the abundant semen proteins prostatic acid phosphatase (PAP) and semenogelins form amyloid fibrils in vitro. These fibrils boost HIV infection and may play a key role in the spread of the AIDS pandemic. However, the presence of amyloid fibrils in semen remained to be demonstrated. Here, we use state of the art confocal and electron microscopy techniques for direct imaging of amyloid fibrils in human ejaculates. We detect amyloid aggregates in all semen samples and find that they partially consist of PAP fragments, interact with HIV particles and increase viral infectivity. Our results establish semen as a body fluid that naturally contains amyloid fibrils that are exploited by HIV to promote its sexual transmission. PMID:24691351

  1. The Ecology of Human-Machine Systems II: Mediating 'Direct Perception' in Complex Work Domains

    DEFF Research Database (Denmark)

    Vicente, Kim J.; Rasmussen, Jens

    1990-01-01

    Recently, a new class of artifacts has appeared in our environment: complex, high-technology work domains. An important characteristic of such systems is that their goal-relevant properties cannot be directly observed by the unaided eye. As a result, interface design is a ubiquitous problem in th...... in the design of these work environments. Nevertheless, the problem is one that has yet to be addressed in an adequate manner. An analogy to human perceptual mechanisms suggests that a smart instrument approach to interface design is needed to supplant the rote instrument (single......-sensor-single-indicator) approach that has dominated to this point. Ecological interface design (ED) is a theoretical framework in the smart instrument vein that postulates a set of general, prescriptive principles for design. The goal of E D is twofold: first, to reveal the affordances of the work domain through the interface...

  2. Neural Plasticity following Abacus Training in Humans: A Review and Future Directions

    Directory of Open Access Journals (Sweden)

    Yongxin Li

    2016-01-01

    Full Text Available The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact.

  3. Direct Genesis of Functional Rodent and Human Schwann Cells from Skin Mesenchymal Precursors

    Directory of Open Access Journals (Sweden)

    Matthew P. Krause

    2014-07-01

    Full Text Available Recent reports of directed reprogramming have raised questions about the stability of cell lineages. Here, we have addressed this issue, focusing upon skin-derived precursors (SKPs, a dermally derived precursor cell. We show by lineage tracing that murine SKPs from dorsal skin originate from mesenchymal and not neural crest-derived cells. These mesenchymally derived SKPs can, without genetic manipulation, generate functional Schwann cells, a neural crest cell type, and are highly similar at the transcriptional level to Schwann cells isolated from the peripheral nerve. This is not a mouse-specific phenomenon, since human SKPs that are highly similar at the transcriptome level can be made from neural crest-derived facial and mesodermally derived foreskin dermis and the foreskin SKPs can make myelinating Schwann cells. Thus, nonneural crest-derived mesenchymal precursors can differentiate into bona fide peripheral glia in the absence of genetic manipulation, suggesting that developmentally defined lineage boundaries are more flexible than widely thought.

  4. Direct effects of FGF21 on glucose uptake in human skeletal muscle

    DEFF Research Database (Denmark)

    Mashili, Fredirick L; Austin, Reginald L; Deshmukh, Atul S

    2011-01-01

    21 were determined in normal glucose tolerant (n = 40) and type 2 diabetic (T2D; n = 40) subjects. We determined whether FGF21 has direct effects on glucose metabolism in cultured myotubes (n = 8) and extensor digitorum longus skeletal muscle. RESULTS: Serum FGF21 levels increased 20% in T2D versus...... normal glucose tolerant subjects (p muscle mRNA expression was unaltered. Fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR), waist circumference, and body mass index (BMI) significantly correlated with serum FGF21 levels in T2D (p ... and insulin-stimulated glucose uptake in human myotubes, coincident with increased glucose transporter 1 mRNA, and enhanced glucose transporter 1 abundance at the plasma membrane. In isolated extensor digitorum longus muscle, FGF21 potentiated insulin-stimulated glucose transport, without altering...

  5. Direct radioimmunoassay of proinsulin and insulin in human plasma by the chromatographic technique

    Energy Technology Data Exchange (ETDEWEB)

    Megahed, Y M; Abdel-Wahab, M F; El-Shawarbie, K; Sadek, S; Amer, M S [Atomic Energy Establishment, Cairo (Egypt). Radioisotope Department; Ain Shams Univ., Cairo (Egypt). Faculty of Medicine)

    1976-04-01

    Specific method for direct radioimmunoassay of IRP and IRI separately in human plasma has been described. The method is used for extraction of total insulin and separation of IRP from IRI by paper chromatography to be assayed separately. The separation of the two components is identified and confirmed by column chromatography, paper chromatography and ultraviolet spectral analysis in comparison with the standard compounds. 134 plasma samples of different cases were investigated for the determination of IRI, IRP and IRT. Out of these 39 were normals, 16 normal obes, 21 juvinil diabetes, 18 overt adult diabetes, 10 recent adult diabetes, 12 hypothyroidism and 18 bilharzial hepatosplenomegaly. They were used to evaluate the test levels in comparison with blood sugar concentration.

  6. 76 FR 51374 - Direct Discovery of HLA Associated Influenza Epitopes Isolated From Human Cells for Vaccine and...

    Science.gov (United States)

    2011-08-18

    ... direct-discovery technology for use in FDA laboratories. C. Eligibility Information The technology...] Direct Discovery of HLA Associated Influenza Epitopes Isolated From Human Cells for Vaccine and... technology to molecularly characterize peptide epitopes that are processed and presented on soluble HLA...

  7. Gaze and power. A post-structuralist interpretation on Perseus’ myth

    Directory of Open Access Journals (Sweden)

    Olaya Fernández Guerrero

    2015-12-01

    Full Text Available Gaze hierarchizes, manages and labels reality. Then, according to Foucault, gaze can be understood as a practice of power. This paper is inspired by his theories, and it applies them to one of the most powerful symbolic spheres of Western culture: Greek Myths. Notions such as visibility, invisibility and panopticism bring new light into the story of Perseus and Medusa, and they enable a re-reading of this Myth focused on the different ways of power that emerge from the gaze.

  8. Human perception of air movement. Impact of frequency and airflow direction on draught sensation

    Energy Technology Data Exchange (ETDEWEB)

    Genhong Zhou

    1999-08-01

    calculates the air velocity and temperature field above and below the skin surface under steady and non-steady conditions. The model predicts the impulses from thermal receptors of skin. The simulation results had a good agreement with the experimental results on subject`s sensation of draught. (au) 130 refs.; covertitle: Human perception of air movement: Impact of frequency and airflow direction on sensation of draught

  9. Flexibility to contingency changes distinguishes habitual and goal-directed strategies in humans.

    Science.gov (United States)

    Lee, Julie J; Keramati, Mehdi

    2017-09-01

    Decision-making in the real world presents the challenge of requiring flexible yet prompt behavior, a balance that has been characterized in terms of a trade-off between a slower, prospective goal-directed model-based (MB) strategy and a fast, retrospective habitual model-free (MF) strategy. Theory predicts that flexibility to changes in both reward values and transition contingencies can determine the relative influence of the two systems in reinforcement learning, but few studies have manipulated the latter. Therefore, we developed a novel two-level contingency change task in which transition contingencies between states change every few trials; MB and MF control predict different responses following these contingency changes, allowing their relative influence to be inferred. Additionally, we manipulated the rate of contingency changes in order to determine whether contingency change volatility would play a role in shifting subjects between a MB and MF strategy. We found that human subjects employed a hybrid MB/MF strategy on the task, corroborating the parallel contribution of MB and MF systems in reinforcement learning. Further, subjects did not remain at one level of MB/MF behaviour but rather displayed a shift towards more MB behavior over the first two blocks that was not attributable to the rate of contingency changes but rather to the extent of training. We demonstrate that flexibility to contingency changes can distinguish MB and MF strategies, with human subjects utilizing a hybrid strategy that shifts towards more MB behavior over blocks, consequently corresponding to a higher payoff.

  10. SMAD7 directly converts human embryonic stem cells to telencephalic fate by a default mechanism

    Science.gov (United States)

    Ozair, Mohammad Zeeshan; Noggle, Scott; Warmflash, Aryeh; Krzyspiak, Joanna Ela; Brivanlou, Ali H.

    2013-01-01

    Human embryonic stem cells (hESCs) provide a valuable window into the dissection of the molecular circuitry underlying the early formation of the human forebrain. However, dissection of signaling events in forebrain development using current protocols is complicated by non-neural contamination and fluctuation of extrinsic influences. Here we show that SMAD7, a cell-intrinsic inhibitor of TGFβ signaling, is sufficient to directly convert pluripotent hESCs to an anterior neural fate. Time-course gene expression revealed down-regulation of MAPK components, and combining MEK1/2 inhibition with SMAD7-mediated TGFβ inhibition promoted telencephalic conversion. FGF-MEK and TGFβ-SMAD signaling maintain hESCs by promoting pluripotency genes and repressing neural genes. Our findings suggest that in the absence of these cues, pluripotent cells simply revert to a program of neural conversion. Hence the “primed” state of hESCs requires inhibition of the “default” state of neural fate acquisition. This has parallels in amphibians, suggesting an evolutionarily conserved mechanism. PMID:23034881

  11. Nicorandil directly and cyclic GMP-dependently opens K+ channels in human bypass grafts

    Directory of Open Access Journals (Sweden)

    Marija Marinko

    2015-06-01

    Full Text Available As we previously demonstrated the role of different K+ channels in the action of nicorandil on human saphenous vein (HSV and human internal mammary artery (HIMA, this study aimed to analyse the contribution of the cGMP pathway in nicorandil-induced vasorelaxation and to determine the involvement of cGMP in the K+ channel-activating effect of nicorandil. An inhibitor of soluble guanylate cyclase (GC, ODQ, significantly inhibited nicorandil-induced relaxation, while ODQ plus glibenclamide, a selective ATP-sensitive K+ (KATP channel inhibitor, produced a further inhibition of both vessels. In HSV, ODQ in combination with 4-aminopyridine, a blocker of voltage-gated K+ (KV channels, did not modify the concentration-response to nicorandil compared with ODQ, whereas in HIMA, ODQ plus iberiotoxin, a selective blocker of large-conductance Ca2+-activated K+ (BKCa channels, produced greater inhibition than ODQ alone. We showed that the cGMP pathway plays a significant role in the vasorelaxant effect of nicorandil on HSV and HIMA. It seems that nicorandil directly opens KATP channels in both vessels and BKCa channels in HIMA, although it is possible that stimulation of GC contributes to KATP channels activation in HIMA. Contrary, the activation of KV channels in HSV is probably due to GC activation and increased levels of cGMP.

  12. A model of human nasal epithelial cells adapted for direct and repeated exposure to airborne pollutants.

    Science.gov (United States)

    Bardet, Gaëlle; Achard, Sophie; Loret, Thomas; Desauziers, Valérie; Momas, Isabelle; Seta, Nathalie

    2014-08-17

    Airway epithelium lining the nasal cavity plays a pivotal role in respiratory tract defense and protection mechanisms. Air pollution induces alterations linked to airway diseases such as asthma. Only very few in vitro studies to date have succeeded in reproducing physiological conditions relevant to cellular type and chronic atmospheric pollution exposure. We therefore, set up an in vitro model of human Airway Epithelial Cells of Nasal origin (hAECN) close to real human cell functionality, specifically adapted to study the biological effects of exposure to indoor gaseous pollution at the environmental level. hAECN were exposed under air-liquid interface, one, two, or three-times at 24 h intervals for 1 h, to air or formaldehyde (200 μg/m(3)), an indoor air gaseous pollutant. All experiments were ended at day 4, when both cellular viability and cytokine production were assessed. Optimal adherence and confluence of cells were obtained 96 h after cell seeding onto collagen IV-precoated insert. Direct and repeated exposure to formaldehyde did not produce any cellular damage or IL-6 production change, although weak lower IL-8 production was observed only after the third exposure. Our model is significantly better than previous ones due to cell type and the repeated exposure protocol. Copyright © 2014. Published by Elsevier Ireland Ltd.

  13. Crystallization and preliminary crystallographic studies of human septin 1 with site-directed mutations

    International Nuclear Information System (INIS)

    Hu, Hao; Yu, Wen-bo; Li, Shu-xing; Ding, Xiang-ming; Yu, Long; Bi, Ru-Chang

    2006-01-01

    The homogeneity of septin 1 has been improved by site-directed mutation of serine residues and only a small alteration in the secondary structure is observed to arise from the mutations. Crystals of the septin 1 mutant were grown and diffraction data were collected to 2.5 Å resolution. Septin 1 is a member of an evolutionarily conserved family of GTP-binding and filament-forming proteins named septins, which function in diverse processes including cytokinasis, vesicle trafficking, apoptosis, remodelling of the cytoskeleton, infection, neurodegeneration and neoplasia. Human septin 1 has been expressed and purified, but suffers from severe aggregation. Studies have shown that septin 1 with site-directed mutations of five serine residues (Ser19, Ser206, Ser307, Ser312 and Ser315) has a much lower degree of aggregation and better structural homogeneity and that the mutations cause only slight perturbations in the secondary structure of septin 1. This septin 1 mutant was crystallized and diffraction data were collected to 2.5 Å resolution. The space group is P422, with unit-cell parameters a = b = 106.028, c = 137.852 Å

  14. Crystallization and preliminary crystallographic studies of human septin 1 with site-directed mutations

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Hao [Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Yu, Wen-bo [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433 (China); Li, Shu-xing [Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Ding, Xiang-ming; Yu, Long [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433 (China); Bi, Ru-Chang [Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China)

    2006-02-01

    The homogeneity of septin 1 has been improved by site-directed mutation of serine residues and only a small alteration in the secondary structure is observed to arise from the mutations. Crystals of the septin 1 mutant were grown and diffraction data were collected to 2.5 Å resolution. Septin 1 is a member of an evolutionarily conserved family of GTP-binding and filament-forming proteins named septins, which function in diverse processes including cytokinasis, vesicle trafficking, apoptosis, remodelling of the cytoskeleton, infection, neurodegeneration and neoplasia. Human septin 1 has been expressed and purified, but suffers from severe aggregation. Studies have shown that septin 1 with site-directed mutations of five serine residues (Ser19, Ser206, Ser307, Ser312 and Ser315) has a much lower degree of aggregation and better structural homogeneity and that the mutations cause only slight perturbations in the secondary structure of septin 1. This septin 1 mutant was crystallized and diffraction data were collected to 2.5 Å resolution. The space group is P422, with unit-cell parameters a = b = 106.028, c = 137.852 Å.

  15. Direct Monte Carlo dose calculation using polygon-surface computational human model

    International Nuclear Information System (INIS)

    Jeong, Jong Hwi; Kim, Chan Hyeong; Yeom, Yeon Su; Cho, Sungkoo; Chung, Min Suk; Cho, Kun-Woo

    2011-01-01

    In the present study, a voxel-type computational human model was converted to a polygon-surface model, after which it was imported directly to the Geant4 code without using a voxelization process, that is, without converting back to a voxel model. The original voxel model was also imported to the Geant4 code, in order to compare the calculated dose values and the computational speed. The average polygon size of the polygon-surface model was ∼0.5 cm 2 , whereas the voxel resolution of the voxel model was 1.981 × 1.981 × 2.0854 mm 3 . The results showed a good agreement between the calculated dose values of the two models. The polygon-surface model was, however, slower than the voxel model by a factor of 6–9 for the photon energies and irradiation geometries considered in the present study, which nonetheless is considered acceptable, considering that direct use of the polygon-surface model does not require a separate voxelization process. (author)

  16. Regenerating the human heart: direct reprogramming strategies and their current limitations.

    Science.gov (United States)

    Ghiroldi, Andrea; Piccoli, Marco; Ciconte, Giuseppe; Pappone, Carlo; Anastasia, Luigi

    2017-10-27

    Cardiovascular diseases are the leading cause of death in the Western world. Unfortunately, current therapies are often only palliative, consequently essentially making heart transplantation necessary for many patients. However, several novel therapeutic approaches in the past two decades have yielded quite encouraging results. The generation of induced pluripotent stem cells, through the forced expression of stem cell-specific transcription factors, has inspired the most promising strategies for heart regeneration by direct reprogramming of cardiac fibroblasts into functional cardiomyocytes. Initial attempts at this reprogramming were conducted using a similar approach to the one used with transcription factors, but during years, novel strategies have been tested, e.g., miRNAs, recombinant proteins and chemical molecules. Although preliminary results on animal models are promising, the low reprogramming efficiency, as well as the incomplete maturation of the cardiomyocytes, still represents important obstacles. This review covers direct transdifferentiation strategies that have been proposed and developed and illustrates the pros and cons of each approach. Indeed, as described in the manuscript, there are still many unanswered questions and drawbacks that require a better understanding of the basic signaling pathways and transcription factor networks before functional cells, suitable for cardiac regeneration and safe for the patients, can be generated and used for human therapies.

  17. Clinical Approach to Supranuclear Brainstem Saccadic Gaze Palsies

    Directory of Open Access Journals (Sweden)

    Alexandra Lloyd-Smith Sequeira

    2017-08-01

    Full Text Available Failure of brainstem supranuclear centers for saccadic eye movements results in the clinical presence of a brainstem-mediated supranuclear saccadic gaze palsy (SGP, which is manifested as slowing of saccades with or without range of motion limitation of eye movements and as loss of quick phases of optokinetic nystagmus. Limitation in the range of motion of eye movements is typically worse with saccades than with smooth pursuit and is overcome with vestibular–ocular reflexive eye movements. The differential diagnosis of SGPs is broad, although acute-onset SGP is most often from brainstem infarction and chronic vertical SGP is most commonly caused by the neurodegenerative condition progressive supranuclear palsy. In this review, we discuss the brainstem anatomy and physiology of the brainstem saccade-generating network; we discuss the clinical features of SGPs, with an emphasis on insights from quantitative ocular motor recordings; and we consider the broad differential diagnosis of SGPs.

  18. Direct numerical simulation of particle laden flow in a human airway bifurcation model

    International Nuclear Information System (INIS)

    Stylianou, Fotos S.; Sznitman, Josué; Kassinos, Stavros C.

    2016-01-01

    Highlights: • An anatomically realistic model of a human airway bifurcation is constructed. • Direct numerical simulations are used to study laminar and turbulent airflow. • Aerosol deposition in the bifurcation is studied with lagrangian particle tracking. • Carinal vortices forming during steady expiration are reported for the first time. • Stokes number determines deposition differences between inspiration and expiration. - Abstract: During the delivery of inhaled medicines, and depending on the size distribution of the particles in the formulation, airway bifurcations are areas of preferential deposition. Previous studies of laminar flow through airway bifurcations point to an interplay of inertial and centrifugal forces that leads to rich flow phenomena and controls particle deposition patterns. However, recent computational studies have shown that the airflow in the upper human airways is turbulent during much of the respiratory cycle. The question of how the presence of turbulence modifies these effects remains open. In this study, we perform for the first time Direct Numerical Simulations (DNS) of fully developed turbulent flow through a single human airway bifurcation model, emulating steady prolonged inspiration and expiration. We use the rich information obtained from the DNS in order to identify key structures in the flow field and scrutinize their role in determining deposition patterns in the bifurcation. We find that the vortical structures present in the bifurcation during expiration differ from those identified during inspiration. While Dean vortices are present in both cases, a set of three dimensional “carinal vortices” are identified only during expiration. A set of laminar simulations in the same geometries, but at lower Reynolds numbers, allow us to identify key differences in aerosol deposition patterns between laminar and turbulent respiration. We also report deposition fractions for representative Stokes numbers for both

  19. Looking back at 'looking back': operationalising referential gaze for dingoes in an unsolvable task.

    Science.gov (United States)

    Smith, Bradley Philip; Litchfield, Carla Anita

    2013-11-01

    This paper examined the performance of dingoes (Canis dingo) on the rope-pulling task, previously used by Miklósi et al. (Curr Biol 13:763-766, 2003) to highlight a key distinction in the problem-solving behaviour of wolves compared to dogs when in the company of humans. That is, when dogs were confronted with an unsolvable task, following a solvable version of the task they looked back or gazed at the human, whereas, wolves did not. We replicated the rope-pulling task using 12 sanctuary-housed dingoes and used the Miklósi et al. (Curr Biol 13:763-766, 2003) definition of looking back behaviour to analyse the data. However, at least three different types of look backs were observed in our study. We, then developed a more accurate operational definition of looking back behaviour that was task specific and reanalysed the data. We found that the operational definition employed greatly influences the results, with vague definitions potentially overestimating the prevalence of looking back behaviour. Thus, caution must be taken when interpreting the results of studies utilising looking back as behaviour linked to assistance seeking during problem solving. We present a more stringent definition and make suggestions for future research.

  20. Gaze recognition in high-functioning autistic patients. Evidence from functional MRI

    International Nuclear Information System (INIS)

    Takebayashi, Hiroko; Ogai, Masahiro; Matsumoto, Hideo

    2006-01-01

    We examined whether patients with high-functioning autistic disorder (AD) would exhibit abnormal activation in brain regions implicated in the functioning of theory of mind (TOM) during gaze recognition. We investigated brain activity during gaze recognition in 5 patients with high-functioning AD and 9 normal subjects, using functional magnetic resonance imaging. On the gaze task, more activation was found in the left middle frontal gyrus, the right intraparietal sulcus, and the precentral and inferior parietal gyri bilaterally in controls than in AD patients, whereas the patient group showed more powerful signal changes in the left superior temporal gyrus, the right insula, and the right medial frontal gyrus. These results suggest that high-functioning AD patients have functional abnormalities not only in TOM-related brain regions, but also in widely distributed brain regions that are not normally activated upon the processing of information from another person's gaze. (author)