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positions of gaze

Vincent K Dik, Ignace T C Hooge, Martijn G H van Oijen, Peter D Siersema
BACKGROUND AND OBJECTIVE: Considerable variation in adenoma detection has been shown between endoscopists, which may be explained by differences in colon inspection. Eye-tracking technology is an objective tool that detects differences in viewing patterns. We investigated the feasibility of eye-tracking technology during real-time, self-performed colonoscopies. METHODS: In this pilot study, 10 endoscopists performed two colonoscopies each. A mobile eye-tracking system to register the right eye position was used to determine the gaze across four areas of interest of the endoscopy monitor (upper, lower, left, and right quadrant)...
December 2016: European Journal of Gastroenterology & Hepatology
Ileok Jung, Seo-Young Choi, Hyo-Jung Kim, Ji-Soo Kim
Even though dizziness is a common symptom of heat illness, comprehensive evaluation of the vestibular function has not been available in this potentially life-threatening disorder. Three patients developed vertigo about a week after heat exposure. Evaluation showed bilateral impairments of the vestibulo-ocular reflex during head impulses and the signs of vestibulocerebellar dysfunction that included spontaneous downbeat nystagmus, gaze-evoked nystagmus, and positional downbeat nystagmus. Exposure to excessive heat may give rise to delayed vestibulopathy by damaging the vestibulocerebellum...
October 20, 2016: Journal of Neurology
Jonathan Denniss, Andrew T Astle
Purpose: To demonstrate methods that enable visual field sensitivities to be compared with normative data without restriction to a fixed test pattern. Methods: Healthy participants (n = 60, age 19-50) undertook microperimetry (MAIA-2) using 237 spatially dense locations up to 13° eccentricity. Surfaces were fit to the mean, variance, and 5th percentile sensitivities. Goodness-of-fit was assessed by refitting the surfaces 1000 times to the dataset and comparing estimated and measured sensitivities at 50 randomly excluded locations...
October 1, 2016: Investigative Ophthalmology & Visual Science
Renfeng Xu, Huachun Wang, Feng Jiang, Chunyan Xue, Zhenping Huang, Arthur Bradley
PURPOSE: We hypothesize that the typically narrower palpebral apertures of East Asian eyes in combination with the narrowing of this aperture during down-gaze combine to reduce light levels and image contrast in the inferior retina during near work, thus creating peripheral deprivation in these eyes that could generate deprivation myopia in children culturally encouraged to perform near work. METHODS: We photographed the right eyes of 53 Chinese children during down-gaze (from 10 to 40 degrees) from the fixation point and the primary gaze position...
October 18, 2016: Optometry and Vision Science: Official Publication of the American Academy of Optometry
Melinda Y Chang, Andrew Shin, Joseph Park, Aaron Nagiel, Robert A Lalane, Steven D Schwartz, Joseph L Demer
PURPOSE: To ascertain deformation of the optic nerve head (ONH) and peripapillary tissues caused by horizontal duction. DESIGN: Prospective, experimental study. METHODS: Optical coherence tomography of the ONH region was performed in 23 eyes of twelve normal volunteers in central gaze and increasing (10, 20, and 30°) adduction and abduction. Main outcome measures were changes from central gaze in the configuration of the ONH and peripapillary tissues in eccentric gazes...
October 14, 2016: American Journal of Ophthalmology
Raza Naseem Malik, Rachel Cote, Tania Lam
BACKGROUND: Skilled walking, such as obstacle crossing, is an essential component of functional mobility. Sensorimotor integration of visual and proprioceptive inputs is important for successful obstacle crossing. The objective of this study was to understand how proprioceptive deficits affect obstacle-crossing strategies when controlling for variations in motor deficits in ambulatory individuals with spinal cord injury (SCI). METHODS: 15 ambulatory individuals with SCI and 15 able-bodied controls were asked to step over an obstacle scaled to their motor abilities under full and obstructed vision conditions...
October 12, 2016: Journal of Neurophysiology
Sung-Hee Kim, David S Zee, Sascha du Lac, Hyo Jung Kim, Ji-Soo Kim
OBJECTIVE: To describe the ocular motor abnormalities in 9 patients with a lesion involving the nucleus prepositus hypoglossi (NPH), a key constituent of a vestibular-cerebellar-brainstem neural network that ensures that the eyes are held steady in all positions of gaze. METHODS: We recorded eye movements, including the vestibulo-ocular reflex during head impulses, in patients with vertigo and a lesion involving the NPH. RESULTS: Our patients showed an ipsilesional-beating spontaneous nystagmus, horizontal gaze-evoked nystagmus more intense on looking toward the ipsilesional side, impaired pursuit more to the ipsilesional side, central patterns of head-shaking nystagmus, contralateral eye deviation, and decreased vestibulo-ocular reflex gain during contralesionally directed head impulses...
October 12, 2016: Neurology
L Ludwig, L McWhirter, S Williams, C Derry, J Stone
Functional coma - here defined as a prolonged motionless dissociative attack with absent or reduced response to external stimuli - is a relatively rare presentation. In this chapter we examine a wide range of terms used to describe states of unresponsiveness in which psychologic factors are relevant to etiology, such as depressive stupor, catatonia, nonepileptic "pseudostatus," and factitious disorders, and discuss the place of functional or psychogenic coma among these. Historically, diagnosis of functional coma has sometimes been reached after prolonged investigation and exclusion of other diagnoses...
2017: Handbook of Clinical Neurology
Maryam Ziaei, Hana Burianová, William von Hippel, Natalie C Ebner, Louise H Phillips, Julie D Henry
Normal adult aging is associated with difficulties in processing social cues to emotions such as anger and also altered motivation to focus more on positive than negative information. Gaze direction is an important modifier of the social signals conveyed by an emotion, for example, an angry face looking directly at you is considerably more threatening than an angry face looking away. In the present study we tested the hypothesis that older adults would show less neural differentiation to angry faces with direct and avert gaze compared to younger people, with the opposite prediction for happy faces...
September 6, 2016: Neurobiology of Aging
Helmut Leder, Aleksandra Mitrovic, Jürgen Goller
We showed that the looking time spent on faces is a valid covariate of beauty by testing the relation between facial attractiveness and gaze behavior. We presented natural scenes which always pictured two people, encompassing a wide range of facial attractiveness. Employing measurements of eye movements in a free viewing paradigm, we found a linear relation between facial attractiveness and gaze behavior: The more attractive the face, the longer and the more often it was looked at. In line with evolutionary approaches, the positive relation was particularly pronounced when participants viewed other sex faces...
July 2016: I-Perception
T Schrom, R Amberg, F Bast
PURPOSE: Plastic surgery on the eyelids for the purpose of aesthetic or functional correction requires precise knowledge of lid anatomy. Changes in the tarsal curvature of the upper eyelid relative to line of vision are important, particularly when a surgical correction of paralytic lagophthalmos is undertaken. We used a computer-based image-processing algorithm to establish a relationship between changes in the curvature of the tarsus relative to the line of vision. MATERIAL AND METHODS: A dynamic, ultrasound examination of the upper eyelids of 100 participants (100 eyes) was performed transpalpebrally using a 7...
March 2016: Ultrasound Int Open
Gina R A Ferrari, Martin Möbius, Amras van Opdorp, Eni S Becker, Mike Rinck
To address shortcomings of purely reaction-time based attentional bias modification (ABM) paradigms, we developed an ABM task that is controlled by eye-tracking. This task allows to assess and train both disengagement from negative pictures and maintained attention to positive pictures. As a proof-of-principle study with an unselected student sample, this positive training (PT; N = 44) was compared to a negative training (NT; N = 42), which reinforced the opposite attentional pattern. Importantly, training trials were completed only if participants performed the correct gaze patterns...
2016: Cognitive Therapy and Research
Per O Folgerø, Lasse Hodne, Christer Johansson, Alf E Andresen, Lill C Sætren, Karsten Specht, Øystein O Skaar, Rolf Reber
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...
2016: Frontiers in Human Neuroscience
Antonio Ivan Lazzarino, Mark Hamer, David Gaze, Paul Collinson, Ann Rumley, Gordon Lowe, Andrew Steptoe
We have previously shown that there is a complex and dynamic biological interaction between acute mental stress and acute release of inflammatory factors into the blood stream in relation to heart disease. We now hypothesize that the presence of chronic psychosocial stress may modify the weight of single test results for inflammation as a predictor of heart disease. Using a cross-sectional design, 500 participants free from heart disease drawn from the Whitehall II study in UK in 2006-2008 were tested for plasma fibrinogen as an inflammatory factor, financial strain as a marker of chronic psychosocial stress, coronary calcification measured using computed tomography, and for plasma high-sensitivity cardiac troponin T (HS-CTnT) as a marker of cardiac risk...
September 20, 2016: Preventive Medicine
Patrick A Sibony
Purpose: To examine the effects of horizontal eye movements on the shape of the peripapillary basement membrane layer (ppBM layer) in patients with papilledema, anterior ischemic optic neuropathy (AION) and normal eyes. Methods: Spectral-domain optical coherence tomography (SD-OCT) axial rasters of the optic nerve were used to analyze the shape of the ppBM layer. We compared registered images in two eye positions: 10° to 15° of adduction and 30° to 40° of abduction from 80 patients (45 with papilledema, 15 with AION, and 20 normal eyes)...
September 1, 2016: Investigative Ophthalmology & Visual Science
Tim H W Cornelissen, Melissa L-H Võ
People have an amazing ability to identify objects and scenes with only a glimpse. How automatic is this scene and object identification? Are scene and object semantics-let alone their semantic congruity-processed to a degree that modulates ongoing gaze behavior even if they are irrelevant to the task at hand? Objects that do not fit the semantics of the scene (e.g., a toothbrush in an office) are typically fixated longer and more often than objects that are congruent with the scene context. In this study, we overlaid a letter T onto photographs of indoor scenes and instructed participants to search for it...
September 19, 2016: Attention, Perception & Psychophysics
Laurence Conty, Nathalie George, Jari K Hietanen
The perception of direct gaze-that is, of another individual's gaze directed at the observer-is known to influence a wide range of cognitive processes and behaviors. We present a new theoretical proposal to provide a unified account of these effects. We argue that direct gaze first captures the beholder's attention and then triggers self-referential processing, i.e., a heightened processing of stimuli in relation with the self. Self-referential processing modulates incoming information processing and leads to the Watching Eyes effects, which we classify into four main categories: the enhancement of self-awareness, memory effects, the activation of pro-social behavior, and positive appraisals of others...
October 2016: Consciousness and Cognition
A Kheradmand, A I Colpak, D S Zee
The differential diagnosis of patients with vestibular symptoms usually begins with the question: is the lesion central or is it peripheral? The answer commonly emerges from a careful examination of eye movements, especially when the lesion is located in otherwise clinically silent areas of the brain such as the vestibular portions of the cerebellum (flocculus, paraflocculus which is called the tonsils in humans, nodulus, and uvula) and the vestibular nuclei as well as immediately adjacent areas (the perihypoglossal nuclei and the paramedian nuclei and tracts)...
2016: Handbook of Clinical Neurology
Ulpukka Isopahkala-Bouret
Midlife professional women's aging experiences, especially the experiences of changing physical appearance, are examined in this study. A discursive-narrative approach is used to analyze interviews of women working in senior professional and managerial jobs in Finland. The decline narrative is not enough to capture the experiences of these women; noticeable signs of aging can indeed have a positive connotation. After looking older and less attractive (in a stereotypical sense), women are no longer being subjected to a sexualized gaze and are taken more seriously...
September 14, 2016: Journal of Women & Aging
Jing Chen, Matteo Valsecchi, Karl R Gegenfurtner
When human observers track the movements of their own hand with their gaze, the eyes can start moving before the finger (i.e., anticipatory smooth pursuit). The signals driving anticipation could come from motor commands during finger motor execution or from motor intention and decision processes associated with self-initiated movements. For the present study, we built a mechanical device that could move a visual target either in the same direction as the participants' hand or in the opposite direction. Gaze pursuit of the target showed stronger anticipation if it moved in the same direction as the hand, compared to that in the opposite direction, as evidenced by decreased pursuit latency, increased lead of the eye to target in positions, decreased saccade rate, and decreased delay at the movement reversal...
September 14, 2016: Journal of Neurophysiology
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